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This week, we kind of sort of wrapped up the Mini Cooper Clubman and are now driving it. Which is quite fortunate in that it was 9 degrees Fahrenheit here this morning - a bit brisk. Cape Girardeau Missouri is blessed with four full 3 month long seasons and the spring and fall are truly a delight. Summer and winter less so. In July it's 100 degrees F and often 80% humidity and we fat boys suffer terribly in the heat.
But the other end of all that is December. The days are so short it is dark by 4:30PM and it can get quite cold. Not Minnesota cold, but cold nonetheless.
We do love the little sports cars. And in the spring and the fall they are deadly weapons of romantic mayhem. But in July, and again in December/January, they are pretty much useless.
We found the Canadian EV heater assembly almost useless. It seemed like a good idea in July when we installed it and Randy Holmes of Canadian EV assured us that this single element heater would somehow be adequate because it was a "special voltage". We never did get together on what that meant or how it could be adequate, but he IS in Canada after all.
Anyway, in December, it was a joke. The show this week was delayed until Monday, largely because I wound up with a 3 hour show. So we cut the heater section and a thing on the Roving Networks instrumentation and got it down to 2. I'll try to include those sections this next week - or sometime.
In any event, and with any level of heat, the Speedster is a seasonal toy car. Bottom line, top line, whatever line, that's the gig. It's great in Spring and Fall, but air conditioning OR heating a small convertible like this is a losing battle however heroically approached.
The ultimate summer and winter car is of course the Cadillac Escalade EXT. And we do have plans to convert it, but his majesty Mr. Jim Husted has taken our project of twin eleven inch Netgains and made it a career move. We'll get them someday. And I'm not going to disable the car until we do. We already have the transmission. But with new battery announcements just around the corner, and this thing requiring a massive 67kWh pack, we'll do that with nextgen batteries.
That leaves the Mini Cooper. We have made some encouraging progress. I guess it's always easier the second time around. We did revise our adapter to include the magnetic pulse pickup from the original engine, and now have a fully functional tachometer, and this has awakened our DME and more importantly, our power steering. Unfortunately, when the RPM falls below 600, after just five or six seconds the power steering kicks out. The ONLY place I need this electric power assist is in parking - typically when creeping along at about 40 rpm. So I have to put in the clutch and REV the motor to get the steering to kick in. ANd I have to do that every few seconds. But it does work.
And it IS nice to have the tach work. Far from a marginal dial in the corner of the car, this tachometer is quite large and centered on the steering wheel. I found it very annoying that it lay there dead.
I actually had some success getting working with the TIMS600 controller by stealing the encoder signal input to the controller. In trying to get it to "work better" I tried several different circuits, and finally loaded it to the point the controller lost encoder input and blew up an IGBT trying to run the motor with errant information.
We had no idea how to fix it, no support whatsoever from either the manufacturer or Metric Mind, where we bought it. Victor has never actually even run one of these controllers or motors for that matter. And the company is in Switzerland and has no interest in supporting it. I found we could order one from a European EV supplier and have it shipped to the states - 12 weeks later.
So we had seen Rinehart Motion Systems PM100DX become available on David Kois web site in a package with a Ford Siemens motor. This is a 100kW controller with a 300v and 600v versions available. And they are in Wilsonville Oregon - they speak English, and in theory might support their product.
They were not too keen on the project initially. We use an MES-DEA 200-250 motor. While not unheard of, it is expensive, and problematical. RMS support for motors is achieved rather by hand - they have to manually tune the parameters to the controller - somewhat by guess - and check the results on a dyno. So we had to ship them our motor. They had to MAKE an adapter for it to put it on the dyno. And while it does give them known support for another motor, how many 200-250's are out there? Actually a few, but not many.
In any event, incredibly they had us a controller and returned our motor in a WEEK. Not bad. Actually, it was phenomenal in this business. I dont' think we've ever gotten ANYTHING in a week.
In tearing down the system, we found some pretty serious damage to the off end mount, the clutch, and incredibly the shaft coupler. The coupler was actually TWISTED and discolored. This had been machined from a solid 4 inch round billet of 4045 hardened steel.
While we were fixing all that, Matthew Hauber thought little of our mid mount "belly band" and devised a much sturdier one of steel.
We built the car back up and installed the RMS 100kw unit.
I will NOT say the installation went smoothly or that this is a device for the novice. Just downloading and installing and configuring the sofware on a Windoze notebook was a bit of a challenge. The variables and indeed the thinking behind the Rinehart is a bit different from what we've done before. And it required some changes to the control wiring.
For example, we had to add a separate precharge relay. The Rinehart uses this relay to precharge the input capacitors through our 500 ohm 25 watt precharge resistor. Then, IT switches the contactor on. We had previously just run the contactor from switched 12v.
While a little more complicated, this is certainly a good system and I would rate it as vastly improved over what we were doing.
Kind of oddly, the unit wants a GROUND as a brake signal for when you put on the foot brake. On all cars I'm aware of, the brake switch puts out 12v. In our case, both the throttle voltage and the brake signal derive from the DME anyway, not from the actual brake switch. But it is of course a +12v signal when you apply the brakes.
I had to build a little box with a MOSFET and three resistors in it. Basically, the drain of the MOSFET is tied to +12v through a current limiting resistor. The junction of the resistor /MOSFET is provided as the output and with the MOSFET off this will be +12v.
The source of the MOSFET is tied to ground. The 12v brake signal is applied to the gate whenever the pedal is applied and causes the MOSFET to go into conduction. MOSFETS have very low forward resistance, and indeed this was an 80 amp MOSFET I had laying around that is also quite fast. Gross overkill, but it should last. When the MOSFET conducts, the output drops to ground. And the RMS appears to be sastisfied with this arrangement.
The RMS has a software startup sequence we found a little peculiar. It has the usual FORWARD and REVERSE 12v inputs. But it REQUIRES both to be at ground during startup. It THEN requires a BRAKE signal and the appropriate FORWARD or REVERSE to appear simultaneously to complete its startup sequence.
i normally just wire FORWARD to 12v, leave REVERSE disconnected, and use the transmission to backup. The advantage being that I can cycle the controller while rolling down the road - occasionally a nice function if it trips out for some reason but can be reset to operation. I've done this with the Curtis 1238 and a Kelly controller quite successfully. It also worked with the TIMS600, but the DME has some requirements to do a cycle as well.
In any event, we wired a single pole double throw toggle switch (surprisingly rare to find). But if you switch into forward or reverse in the wrong order, or without the brake applied, it not only doesn't respond But it seems you have to reset it and go through the sequence again. This is NOT natural or OK frankly. If you don't actually "know" to do all this, you'll never get the car going and I rate it a human factors faux pas.
It probably does have some salutory safety merits, but not many.
We did notice that they had some unused digital inputs. And we requested that they do some software changes to let us use this with a switched ground input to disable all regenerative braking. We don't actually have this feature on the Curtis 1238, but did have on the TIMS600. And I liked it. In inclement weather, I'm a little uneasy with regen. It is only applied to the front wheels, and you have less control of your braking, and are actually braking when you take your foot off the accelerator. On ice, this doesn't sound like a good idea. I haven't actually tried it yet, but it would seem even a little braking action on the front wheels on glare ice, performed by the not very active action of REMOVING your foot from the accelerator, is a disaster in the making.
They revised their software to include this feature. If you apply a ground to digital input 4 it will disable regen entirely. In the video, I noted that it only disabled accelerator regen, but I've already gotten a firmware update fixing it.
Along the way, we've had four or five phone calls, a dozen e-mails, and three firmware updates. Chris Brune is very calm, very professional, not at all in the "you guys are a bunch of idiots" camp I run into so often. Very helpful and very professional.
Is this controller ready for prime time? The fit and finish mechanically is just GORGEOUS. We're driving the car and it makes not only good power, but it feels more "appropriate" to the Mini Cooper than what we had, which was probably overkill. We're running 340 volts now at up to 300 amps and generally under 100kw, which is what this is rated for.
My take is that it is kind of in a prototype stage. This is four or five guys, struggling for life in a kind of hostile world, with a limited market. They build few. And so the pricing is very high, and very mercurial. The unit lists for an astronomical $9500. They sold us ours for $6500. And they allude to a deal with Remy that could get them into "production' more in the $4500 mark. So I can't make it out. I don't know what it is or what it might be so it's kind of hard to talk about value. I paid it gladly.
The configuration software is plain but quite well done. It will take a little getting used to and you do have to RTFM. But once accustomed to it, I like it. I found some of the variables a little bizarre and a little immature. We have GREAT configuration options on the accelerator, and almost NONE on the braking regen for example. But it is all software and as I said, we had three firmware upgrades in a month for this project. It will certainly get there.
On a broader front, I find the 650v AC solutions simply impractical for an EV. None of the peripheral items, DC-DC converters, water heaters, air conditioner compressors, etc can work at those voltages. While Rinehart has a 600v version of this controller, we found the 300v (up to 360v) perfect for this application.
So while it felt a little like we were on the beta team, and while I would admonish that "some assembly is required" and a complete novice probably does NOT want to use this controller. But that said, I'm kind of picturing a package with a Remy or other motor, with the whole gig somewhere this side of $10K, as being quite viable. The 100kw is PLENTY of power for a 3500-4000 lb vehicle if you have no NEDRA aspirations. Obviously in a sports car it WOULD be competitive. A Speedster with this in it would just be over the edge.
I think if these guys has a few installations of this controller and an appropriate motor out there to waive the flag publicly and work out a few of the software issues, it has a GREAT future.
A very interesting aside, and part of the reason I'm so impressed with this device, goes to our heat redux. We had a TREMENDOUS amount of heat from the TIMS600 and MES-DEA motor. It was incredible. We actually used the MINI radiator to cool it and found we had to turn on the radiator FAN to adequately cool it.
Same motor with the RMS PM100DX barely gets warm. Now it IS true we went from a 375v 400AMP system to a 340V 300 amp configuration. But the change in heat was dramatic. I'm guess that in addition to being 25% smaller, this controller is also much more efficient.
And that allowed us a very interesting experiment. We SHITCANNED the Mezzier pump and BUNCH of expensive Summit Racing hose work, along with a complicated fill and bleed procedure. We took the pump output of our 4kw heater, which comes from the heater core, and routed that through the controlller first, the motor second (both are liquid cooled) and thence back to the 4kw heater bottle which feeds the heater core.
This little loop is both interesting, and very unlikely to be effective. The heater core of course has a temperature drop, winter or summer, on or off. So it SEEMS adequate to cool the drive train - of course it does in December. We'll SEE next July.
We rewired the pump to run whenever the ignition is on. But kept the heater elements on a manual switch.
So I can drive down the road and get a very modest amount of heat from the motor and controller - more on the highway of course. And if I need more, I can turn on the 4kw heater element.
Now this is a bit counterintuitive. Our heater doesn't work as well as it did. It is actually HEATING the controller and motor, and the loop is bigger with more coolant in it. So it takes longer to get up to temperature. But at 8F, we are still getting a pretty warm car I would say in five or seven minutes. Previously three minutes. It's very nice after 10 minutes.
The heater is hard set at about 65C. Of course, there IS a pretty good temperature drop across the heater core. The Mini heater is quite efficient at extracting heat from this core. So I would guess the temps coming OUT of the heater core are a good 15C below that or 50C. With good flow, the RMS is rated at an inlet temperature up to 80C. The motor frankly doesn't matter at these power levels. So with the heater on, and after running for a few minutes, I think we're going IN to the heater core at 65C, coming out of heater core and into RMS at 50C, and coming out of RMS and MOTOR into heater back at about 60-65C.
This very unlikely system seems to work very well at this point. It remains to be seen if it can "hold water" in the summer.
Of course, in the summer we would never have the heater element on. But with the heater fan off (or diverter to A/C) we are not going to get as much temp drop across the heater core as well. I'm hoping for 10C. With a 40C ambient, (hot day) whether or not 10C cooling will keep the controller under 80C is a big question. I'm guessing at this point that it will. But we'll just have to test it to find out.
If NOT, we'll have to have a summer rig with a little heat exchanger that can be cut into the loop between the pump and the controller input. This is not a hard "get well" in any event - almost trivial.
So the good news is that the Mini Cooper drives well and that it heats/cools within parameters. And actually the heater, which you would not say "will run you out of here" it is comfortable on very cold days.
And unlike the Speedster, we have all the other creature comforts. Bluetooth phone, HEATED seat warmers, Sirius Satellite Radio, windshield washers, EFFECTIVE windshield wipers (actually I think we even have headlight washers and wipers) all the comforts of home and a modern automobile.
The Mini Cooper has been a much more complicated project than we bought into and a much more expensive one. We undoubtedly have $75K in this car at this point - but I think we did better than BMW on the expense side.
Rate Rinhart Motion Systems and the PM100DX a comer. And better, with Oregon based support in English, and in our case outstanding support at that. That's a BIG issue as we've learned the hard way on the 2009 Mini Cooper Clubman Electric.
Jack Rickard
Tuesday, December 14, 2010
Monday, December 6, 2010
What HE Said. What I said.
I ran across a very interesting video courtesy of viewer Brandon Hollinger http://ampREVOLT.com/. Brandon has done a lead acid conversion of a 1970 Saab 96 that looks quite well done for a Pb car. And he's started a LiFePo4 Miata project for someone else.
Jay Whitacre received his Phd in Materials Science in 1999 at University of Michigan Ann Arbor - so he's a lot smarter than I am. He worked for Jet Propulsion Laboratory 2000-2007 mostly on lithium battery projects. Today, he is an assistant professor in Materials Science at Carnegie Mellon university. He's also head of Whitacre Research Group which studies functional materials for electrochemical storage.
The group received a $5 million DOE grant for the development of a Sodium battery using a Sodium Metal Oxide cathode (Na4Nm9O18) with an aqueous electrolyte. These cells are 1.6 volts or thereabouts and a scant 45 Wh per kilogram. But they are totally benign, have a cycle life well over 5000 cycles, and cost about as much as lead acid cells to produce. Because of the low energy density, they are probably not suitable for electric vehicles. But for grid storaage, they are ideal. Inexpensive, rugged, very long lifetimes, environmentally totally benign, easily scalable, and did I mention inexpensive. Like buying lead acid cells that last 20 years and have no lead. The spinoff company is Aquion Energy.
They apparently do not have a web site up but HERE is a bit more about their product development.
In this video, Professor Whitacre addresses a group of EV guys to explain the chemical processes of Thundersky LiFePo4 cells.
The presentation is very interesting and answers a number of temperature questions quite well I thought. Amazingly, at about 1:05 into the presentation he's taking questions regarding Battery Management Systems. And he basically tells this group, who are all totally convinced you have to have a BMS, that essentially NO manufacturer, including Tesla, GM, and Toyota, use a cell level BMS and in fact are moving away from the module management they have now as just too expensive and apparently unnecessary. He stresses EXACTLY what I've been saying, closely matched capacities and string level management.
I found it fascinating. So I thought we'd store the video on our Amazon server and create a blog entry for reference.
Enjoy
Jack Rickard
Jay Whitacre received his Phd in Materials Science in 1999 at University of Michigan Ann Arbor - so he's a lot smarter than I am. He worked for Jet Propulsion Laboratory 2000-2007 mostly on lithium battery projects. Today, he is an assistant professor in Materials Science at Carnegie Mellon university. He's also head of Whitacre Research Group which studies functional materials for electrochemical storage.
The group received a $5 million DOE grant for the development of a Sodium battery using a Sodium Metal Oxide cathode (Na4Nm9O18) with an aqueous electrolyte. These cells are 1.6 volts or thereabouts and a scant 45 Wh per kilogram. But they are totally benign, have a cycle life well over 5000 cycles, and cost about as much as lead acid cells to produce. Because of the low energy density, they are probably not suitable for electric vehicles. But for grid storaage, they are ideal. Inexpensive, rugged, very long lifetimes, environmentally totally benign, easily scalable, and did I mention inexpensive. Like buying lead acid cells that last 20 years and have no lead. The spinoff company is Aquion Energy.
They apparently do not have a web site up but HERE is a bit more about their product development.
In this video, Professor Whitacre addresses a group of EV guys to explain the chemical processes of Thundersky LiFePo4 cells.
The presentation is very interesting and answers a number of temperature questions quite well I thought. Amazingly, at about 1:05 into the presentation he's taking questions regarding Battery Management Systems. And he basically tells this group, who are all totally convinced you have to have a BMS, that essentially NO manufacturer, including Tesla, GM, and Toyota, use a cell level BMS and in fact are moving away from the module management they have now as just too expensive and apparently unnecessary. He stresses EXACTLY what I've been saying, closely matched capacities and string level management.
I found it fascinating. So I thought we'd store the video on our Amazon server and create a blog entry for reference.
Enjoy
Jack Rickard
Sunday, December 5, 2010
Cycle Life, Chargers, and Instrumentation
This week we resume after our Thanksgiving break. ;We have a lot of little things going on, and some recurring questions I've finally a minute to form some kind of cogent explanation for that won't sound like total nonsense.
The first had to do with cycle life. Understanding how it is calculated is the key to knowing what it IS and that knowledge in turn indicates what you should DO about it. We received some information last June from CALB - actually some test data and I converted that to a Microsoft Excel graph to make it a bit more visual.
The first had to do with cycle life. Understanding how it is calculated is the key to knowing what it IS and that knowledge in turn indicates what you should DO about it. We received some information last June from CALB - actually some test data and I converted that to a Microsoft Excel graph to make it a bit more visual.
We also address some issues with charging and chargers surrounding how the charger determines the voltage point and where to switch from a constant current mode to a constant voltage mode.
We give a first look at the Current Ways programmable charger.
And we have installed and already since filming the video we have gotten WORKING the EVWorks Zeva2 Fuel Gage driver device. I LOVE this little unit. Counts AH and drives a fuel gage to give you a more or less ACCURATE indication of your battery SOC based on AH.
It ALSO provides a pulsed output for instantaneous video - which you can use to display current on your existing tachometer.
Finally, it provides an alarm output to drive an LED if you reach a certain point in DOD. We'll eventually use this for switching in a reistor across our throttle to provide a "limp mode".
Enjoy
jack RIckard
Sunday, November 28, 2010
Turkey Day and Spyder 550 Battery Balance
Well, it's the week of Turkey Day, and as one of the larger and less flight prone Turkeys in the area, a time that always makes me uneasy.
Actually, both my wife and I are excellent cooks, accounting for my unfortunate girth, and Thanksgiving is one of my favorite holidays. Family visit and good food, with none of the preparatory stress of Christmas or the insect life of the 4th of July.
So, I've finally gotten around to posting LAST week's video to the blogosphere. Vanity of vanities - someone might care.
Actually, it was a pretty good show. We ran two cars down to pretty much the bottom of the power pile and took some interesting measurements. I alluded to these earlier.
Speedster the original was run to a full stop. In fact, it stopped about six times on the way back to the shed. I would let it sit for about 5 minutes and the cells recovered enough to go another 150 yards or so. Ultimately we pushed it into our new facility at 601 Morgan Oak. All cells were low but the first six cells on the front string were all actually below 0.500 v measured statically 10 minutes later. So they must have been flat zero in operation.
We are going to rebuild this Speedster anyway with a new motor, different controller, and entirely different battery pack, so I was curious. Put a slow charge on the pack and ALL cells came right back up to perfect working levels. I won't say we did these six any good, but the car is driving nicely and they seem to be perfectly happy at the moment.
The Spyder 550 was more interesting in that we did NOT run it entirely out. The 157 km trip used 176.5 AH of the 180 available and we still had cells above 3.00v. So I sent Matt for a couple of sleds of Stag Beer and by the time he got back at 183 AH they were all nicely below 3.00v.
The list of voltages tells the tale. The cells were very nicely balanced. Understand this pack had 5500 km on it and first rolled last June. It had never been top balanced, and never bottom balanced. The cells were simply installed in the car as received from the manufacturer, strapped up, and charged with the BRUSA NLG511 charger.
One thing that jumped out at me was that the first 10 cells were noticeably lower than the rest, but not randomly so. It almost looked like the first 10 were different. A graph of this makes it clearer.
Initially I thought it might have something to do with cooling and air flow since they were all in the front, but there were actually 12 cells in front, not 10.
Then I remembered the Xantrex episode. We had used a TBS Expert Pro on the Mini Cooper and powered it with the first 10 cells. The unit draws less than 60 ma so how much damage can it do to a 100AH pack? Well plenty as it turns out. It's on 24x7 and after a couple of months, they were 10 AH down. Then I recalled that Duane had been following our progress on this and had replicated our mistake. Eventually he also replicated the solution - a voltage divider across the entire pack. We've since moved to DC-DC converters actually. But the cells remained slightly drained from the originals that hadn't had that treatment.
About 15 amps for 5 minutes dressed it all up. Cell 28 was also a spot down so it got 30 seconds.
That was the fix.
We just flat did not do a show during Thanksgiving week. We have a lot going on with the Mini Cooper, but I've also taken THAT battery pack down to parade rest and we are wanting to look at all the cells while we have it down. That will take some effort as they are much harder to get to than our other cars. Thank goodness I let Brain talk me into the $550 rail/drawer system for the box inside or it would really be difficult. Anyway, we're going to measure all of them this week and tighten all the connections while we're there.
The Rinehart controller has been interesting. It has fought us every step of the way, but I think it's going to get there on the 2009 Mini Cooper Clubman. First, they gave us the wrong motor type code by accident and it did NOT run very well. That fixed, we found an even more unnerving issue. When in electronic REVERSE, if you step on the BRAKE it ACCELERATES the car. It's a little counterintuitive to get it to stop too - let off the brake and sieze the hand brake and haul in on it with all your strength. THAT was exciting. But again, it's simply a software problem and Chris Brune has been very communicative. We isolated it to just REVERSE and he was able to forward us new firmware WITHOUT this little feature literally within four or five hours. That's why they call it software.
The controller is clearly in the prototype area. The hardware design is very attractive. And I'm getting accustomed to the software to configure it. It's actually not bad. The controller is limited to 300 AMPS at up to 360V whereas the TIMS600 was 400A at up to 400V. So it's a bit tamer in actual operation. But that's not entirely a bad thing. As I've preached numerous times, and to little effect with all the power worshipping gearheads, sometimes more is just more. I confess I liked the responsiveness of the TIMS600. But the Rinehart drives the car very nicely and with nothing to apologize for. We're doing more in 2nd gear that we used to do in 3rd - we have the luxury of 6 gears to choose from and so that's all good. It's running nicely at the moment. We are chasing a little gremlin where the controller cuts out entirely. But I think we have traced it to a cable beneath our own 12v DC-DC converter that had worn a spot through to the case and was intermittently shorting the 12v bus - cutting out the contactor.
Chasing intermittents is always interesting because they are, well, intermittent. So if you do something, and it appears to fix it, that's all good unless it was just occupying the good part of the "intermittent" curve by coincidence. But I really do think we have this one.
So we went on strike this week on video and we'll cover all that next week, after we are a little smarter. The time off has given me time to play with a back burner project that is kinda cool, and a bit frustrating. I'm doing it on a Mac OS X machine in Objective C using Xcode and the Interface Builder. This is it's own little world of madness. Mac guys have always been on the EXTREME end of weird. Mostly, they know NOTHING about computers or software design yet somehow manage to achieve superstardom as DIVAS of software design. Just reading the books on the topic is a horror - page after page after page of trivial piff and tosh about absolutely NOTHING all to carry a bare structure of a little bit of information about the system. The information density is EXTREMELY low.
Objective C holds to the hide. It is inherited from NextStep - the OS Steve Jobs made Apple buy as part of his return from the wilderness. The NeXT computer was actually quite interesting in its day. But Objective C is a very strange language. All Object oriented software traces its roots to SmallTalk and LIsp - two very early experiments in object oriented design. Ultimately, C++ and Java emerged as more mature views of this concept. Objective - C is a more direct decendant of SmallTalk. Everything is an object, and it all works on "messages" between objects. The syntactic form of Object.Property that works so well in C++ is replaced by inverted looking messages such as [Object propertyGetter: this one] that I think is just ridiculous on the face of it. You can stack all of this inside bracket set after bracket set. You wind up with programs that are quite short, but with 200 character lines.
And the back and forth between the IDE and the programmatics is just hopeless.
But oddly, you can come up with a reasonably good result in a fairly short period of time, and I suppose that of course gains with familiarity. A lot of iPhone development is going on this way.
In any event, I've been trying to develop a display program that in fairly modular fashion can access serial data streams, and use them to calculate EV interesting things, and then display them in some rational form. So far, I have a Roving Networks Sensor that has 8 16-bit A/D converters in it and reports all the results over bluetooth wireless. I can use this to measure currents and voltages without the usual isolation issues. Then, I have a cheap $36 Globalsat BU 335 GPS unit plugged into the USB port, converted to a serial port with a driver. And I can capture GPS streams.
This gives me speed and its integral, distance.
So I'm trying to glom all that together into something responsive enough and attractive enough to serve as an instrumentation system. But wiring up hardware for it, writing software for it, and learning an entirely new to me operating system and programming language is a bit of a stretch. If I could do just that, I think it would all be cool. But to build EV's, videorecord THAT, edit THOSE and work on a way to display them globally where anyone could actually download one, kind of limits the time I can spend with such programming projects.
In any event, here are a couple of screen captures to show some progress. I'm actually having a lot of fun with it....
Actually, both my wife and I are excellent cooks, accounting for my unfortunate girth, and Thanksgiving is one of my favorite holidays. Family visit and good food, with none of the preparatory stress of Christmas or the insect life of the 4th of July.
So, I've finally gotten around to posting LAST week's video to the blogosphere. Vanity of vanities - someone might care.
Actually, it was a pretty good show. We ran two cars down to pretty much the bottom of the power pile and took some interesting measurements. I alluded to these earlier.
Speedster the original was run to a full stop. In fact, it stopped about six times on the way back to the shed. I would let it sit for about 5 minutes and the cells recovered enough to go another 150 yards or so. Ultimately we pushed it into our new facility at 601 Morgan Oak. All cells were low but the first six cells on the front string were all actually below 0.500 v measured statically 10 minutes later. So they must have been flat zero in operation.
We are going to rebuild this Speedster anyway with a new motor, different controller, and entirely different battery pack, so I was curious. Put a slow charge on the pack and ALL cells came right back up to perfect working levels. I won't say we did these six any good, but the car is driving nicely and they seem to be perfectly happy at the moment.
The Spyder 550 was more interesting in that we did NOT run it entirely out. The 157 km trip used 176.5 AH of the 180 available and we still had cells above 3.00v. So I sent Matt for a couple of sleds of Stag Beer and by the time he got back at 183 AH they were all nicely below 3.00v.
The list of voltages tells the tale. The cells were very nicely balanced. Understand this pack had 5500 km on it and first rolled last June. It had never been top balanced, and never bottom balanced. The cells were simply installed in the car as received from the manufacturer, strapped up, and charged with the BRUSA NLG511 charger.
One thing that jumped out at me was that the first 10 cells were noticeably lower than the rest, but not randomly so. It almost looked like the first 10 were different. A graph of this makes it clearer.
Initially I thought it might have something to do with cooling and air flow since they were all in the front, but there were actually 12 cells in front, not 10.
Then I remembered the Xantrex episode. We had used a TBS Expert Pro on the Mini Cooper and powered it with the first 10 cells. The unit draws less than 60 ma so how much damage can it do to a 100AH pack? Well plenty as it turns out. It's on 24x7 and after a couple of months, they were 10 AH down. Then I recalled that Duane had been following our progress on this and had replicated our mistake. Eventually he also replicated the solution - a voltage divider across the entire pack. We've since moved to DC-DC converters actually. But the cells remained slightly drained from the originals that hadn't had that treatment.
About 15 amps for 5 minutes dressed it all up. Cell 28 was also a spot down so it got 30 seconds.
That was the fix.
We just flat did not do a show during Thanksgiving week. We have a lot going on with the Mini Cooper, but I've also taken THAT battery pack down to parade rest and we are wanting to look at all the cells while we have it down. That will take some effort as they are much harder to get to than our other cars. Thank goodness I let Brain talk me into the $550 rail/drawer system for the box inside or it would really be difficult. Anyway, we're going to measure all of them this week and tighten all the connections while we're there.
The Rinehart controller has been interesting. It has fought us every step of the way, but I think it's going to get there on the 2009 Mini Cooper Clubman. First, they gave us the wrong motor type code by accident and it did NOT run very well. That fixed, we found an even more unnerving issue. When in electronic REVERSE, if you step on the BRAKE it ACCELERATES the car. It's a little counterintuitive to get it to stop too - let off the brake and sieze the hand brake and haul in on it with all your strength. THAT was exciting. But again, it's simply a software problem and Chris Brune has been very communicative. We isolated it to just REVERSE and he was able to forward us new firmware WITHOUT this little feature literally within four or five hours. That's why they call it software.
The controller is clearly in the prototype area. The hardware design is very attractive. And I'm getting accustomed to the software to configure it. It's actually not bad. The controller is limited to 300 AMPS at up to 360V whereas the TIMS600 was 400A at up to 400V. So it's a bit tamer in actual operation. But that's not entirely a bad thing. As I've preached numerous times, and to little effect with all the power worshipping gearheads, sometimes more is just more. I confess I liked the responsiveness of the TIMS600. But the Rinehart drives the car very nicely and with nothing to apologize for. We're doing more in 2nd gear that we used to do in 3rd - we have the luxury of 6 gears to choose from and so that's all good. It's running nicely at the moment. We are chasing a little gremlin where the controller cuts out entirely. But I think we have traced it to a cable beneath our own 12v DC-DC converter that had worn a spot through to the case and was intermittently shorting the 12v bus - cutting out the contactor.
Chasing intermittents is always interesting because they are, well, intermittent. So if you do something, and it appears to fix it, that's all good unless it was just occupying the good part of the "intermittent" curve by coincidence. But I really do think we have this one.
So we went on strike this week on video and we'll cover all that next week, after we are a little smarter. The time off has given me time to play with a back burner project that is kinda cool, and a bit frustrating. I'm doing it on a Mac OS X machine in Objective C using Xcode and the Interface Builder. This is it's own little world of madness. Mac guys have always been on the EXTREME end of weird. Mostly, they know NOTHING about computers or software design yet somehow manage to achieve superstardom as DIVAS of software design. Just reading the books on the topic is a horror - page after page after page of trivial piff and tosh about absolutely NOTHING all to carry a bare structure of a little bit of information about the system. The information density is EXTREMELY low.
Objective C holds to the hide. It is inherited from NextStep - the OS Steve Jobs made Apple buy as part of his return from the wilderness. The NeXT computer was actually quite interesting in its day. But Objective C is a very strange language. All Object oriented software traces its roots to SmallTalk and LIsp - two very early experiments in object oriented design. Ultimately, C++ and Java emerged as more mature views of this concept. Objective - C is a more direct decendant of SmallTalk. Everything is an object, and it all works on "messages" between objects. The syntactic form of Object.Property that works so well in C++ is replaced by inverted looking messages such as [Object propertyGetter: this one] that I think is just ridiculous on the face of it. You can stack all of this inside bracket set after bracket set. You wind up with programs that are quite short, but with 200 character lines.
And the back and forth between the IDE and the programmatics is just hopeless.
But oddly, you can come up with a reasonably good result in a fairly short period of time, and I suppose that of course gains with familiarity. A lot of iPhone development is going on this way.
In any event, I've been trying to develop a display program that in fairly modular fashion can access serial data streams, and use them to calculate EV interesting things, and then display them in some rational form. So far, I have a Roving Networks Sensor that has 8 16-bit A/D converters in it and reports all the results over bluetooth wireless. I can use this to measure currents and voltages without the usual isolation issues. Then, I have a cheap $36 Globalsat BU 335 GPS unit plugged into the USB port, converted to a serial port with a driver. And I can capture GPS streams.
This gives me speed and its integral, distance.
So I'm trying to glom all that together into something responsive enough and attractive enough to serve as an instrumentation system. But wiring up hardware for it, writing software for it, and learning an entirely new to me operating system and programming language is a bit of a stretch. If I could do just that, I think it would all be cool. But to build EV's, videorecord THAT, edit THOSE and work on a way to display them globally where anyone could actually download one, kind of limits the time I can spend with such programming projects.
In any event, here are a couple of screen captures to show some progress. I'm actually having a lot of fun with it....
Regards;
Jack Rickard
Sunday, November 14, 2010
Copy This Linc (Volt).
Interesting week. We had a visit from Wayne Alexander of EV-Blue Conversions in Walton Kansas. We had a great time talking, which he does love to do, and I may have overrun my budget of time for him on the show, but I thought I would include most of it for a couple of reasons.
We're very unlike in our approach to EV's, yet we hit it off rather marvelously. He's been doing them for a very long time (since 1974) and more recently he does a LOT of them (143 in the past four years). So while we agree on little, I thought it important you hear what he has to say.
Wayne does EV for food. He'll convert anything for $12,500. That's a lead acid conversion, and we all know my feelings about lead. But he makes a case. People want to drive electric, and their budget is not unlimited. He's done some LiFePo4, but is clearly more comfortable with lead.
He favors standard components - Netgain motors and Curtis controllers. And he winds up doing 35-40 cars per year.
We actually had a ball talking about all of that. He'll put in anything the customer wants, but those are the designs he considers his bread and butter.
I had a great segment on a 100 mile drive we made in the Speedster AND the Spyder. Ran the Speedster entirely out and the Spyder down to parade rest and had some interesting results from that - two cars with some significant time and miles, living BMS free one day at a time. But I cut that out - we'll push it to next weeks show.
About a year ago I got a call from Jonathan Goodwin. He mostly converts Hummers to biodiesel, but had gotten involved in a project with Neil Young on a 1959 Lincoln Continental they were calling the Linc Volt. Apparently Neil had seen the videos and kind of got enthused, as he is wont to do about a lot of things. I talked with Goodwin and Perrone at length about the immediate questions and implored them to eschew the BMS top balance thing etc. of course.
Neil started corresponding by e-mail and by telephone quite extensively. We talked about them driving through Cape Girardeau on a cross country trip they were planning in the Linc Volt and he was going to do a documentary on it. In fact, we discussed something even more bizarre, going partners with him on his 1938 Meteor - a classic wooden launch that we would power by battery and capstone Turbine.
The Linc Volt had a bit of a secret life. They had decided they could use a Wankel engine and a UQM generator to build a hydrolyzer to make hydrogen, then use the hydrogen to run the Wankel in the usual copper foil helmet concept of perpetual motion. We argued over this somewhat heatedly for some time, and Young had an uncanny ability to catch me on the phone when I was deep in the garage among the wiskey barrels.
In any event, the Meteor never got done. But the capstone went into the Link Volt and the Wankel hydrogen thing went away.
The car came out to be absolutely stunning. Ostensibly 50 miles using High Power cells (not my recommendation frankly but less expensive). And with the Capstone Turbine, a 400 mile range running on natural gas, diesel, biodiesel, etc. The turbines are heavy, and they start at about $30,000. But he wants to do this cross country thing.
The guy filming the documentary was a close friend, and he died suddenly last January.
In any event, they wound up keynoting the SEMA show November 2nd and the Linc Volt was a huge hit. She was all dressed up, and everywhere to go. Young gave an impassioned speech about the need for no compromises go green with large cars that people like. On this, he is so all over it. Right now buyers are returning to the Escalade, Yukon and Denali in droves and you can't give a Prius away at all.
On November 9, in the early AM, the Linc Volt burned to the ground, taking a good bit of warehouse with it. It was definitely the car that started the fire. They are alluding to a "problem charging" with human error. The human error was having a BMS on it, and using it to control the charging of the car of course. Took the fire department most of an hour to get it out.
The car was truly beautiful. The message was beautiful. And Young was passionate about it. I'm crushed, and I never got to see the car and indeed Young and I have never met except by e-mail and phone. I can imagine how he feels about it. He CAN'T imagine how I do. Those dirty BMSs. You try rubbing them out and scrubbing them out, still everybody in the country is UNANIMOUS - you HAVE to have a BMS. They burn cars to the ground.
I've got some contacts in the battery scene. They provided me some shots from the SH2 battery trade show in Shenzhen China - including some shots of the new Gray cells that I'm now told will be available in February. The company naturally doesn't want to hurt current cell sales by announcing any of this before the switchover is announced. They also were showing a blue 200AH cell and a blue 210 AH cell that was very short but wide. I can't wait to get more information on these new batteries. I think this will be important.
We have the motor and transmission back in the Mini Cooper. The new controller is mounted. And we've made some very interesting changes in the cooling and heating systems in the car - we've combined them into one. It can't possibly work. But I've kind of decided to start from the assumption that the controller and motor CAN heat the car, and the car CAN cool the motor and controller, and work backwards from there, adding components until it either does or doesn't. Should be interesting.
Jack Rickard
We're very unlike in our approach to EV's, yet we hit it off rather marvelously. He's been doing them for a very long time (since 1974) and more recently he does a LOT of them (143 in the past four years). So while we agree on little, I thought it important you hear what he has to say.
Wayne does EV for food. He'll convert anything for $12,500. That's a lead acid conversion, and we all know my feelings about lead. But he makes a case. People want to drive electric, and their budget is not unlimited. He's done some LiFePo4, but is clearly more comfortable with lead.
He favors standard components - Netgain motors and Curtis controllers. And he winds up doing 35-40 cars per year.
We actually had a ball talking about all of that. He'll put in anything the customer wants, but those are the designs he considers his bread and butter.
I had a great segment on a 100 mile drive we made in the Speedster AND the Spyder. Ran the Speedster entirely out and the Spyder down to parade rest and had some interesting results from that - two cars with some significant time and miles, living BMS free one day at a time. But I cut that out - we'll push it to next weeks show.
About a year ago I got a call from Jonathan Goodwin. He mostly converts Hummers to biodiesel, but had gotten involved in a project with Neil Young on a 1959 Lincoln Continental they were calling the Linc Volt. Apparently Neil had seen the videos and kind of got enthused, as he is wont to do about a lot of things. I talked with Goodwin and Perrone at length about the immediate questions and implored them to eschew the BMS top balance thing etc. of course.
Neil started corresponding by e-mail and by telephone quite extensively. We talked about them driving through Cape Girardeau on a cross country trip they were planning in the Linc Volt and he was going to do a documentary on it. In fact, we discussed something even more bizarre, going partners with him on his 1938 Meteor - a classic wooden launch that we would power by battery and capstone Turbine.
 |
| 1938 Meteor |
The Linc Volt had a bit of a secret life. They had decided they could use a Wankel engine and a UQM generator to build a hydrolyzer to make hydrogen, then use the hydrogen to run the Wankel in the usual copper foil helmet concept of perpetual motion. We argued over this somewhat heatedly for some time, and Young had an uncanny ability to catch me on the phone when I was deep in the garage among the wiskey barrels.
In any event, the Meteor never got done. But the capstone went into the Link Volt and the Wankel hydrogen thing went away.
The car came out to be absolutely stunning. Ostensibly 50 miles using High Power cells (not my recommendation frankly but less expensive). And with the Capstone Turbine, a 400 mile range running on natural gas, diesel, biodiesel, etc. The turbines are heavy, and they start at about $30,000. But he wants to do this cross country thing.
The guy filming the documentary was a close friend, and he died suddenly last January.
In any event, they wound up keynoting the SEMA show November 2nd and the Linc Volt was a huge hit. She was all dressed up, and everywhere to go. Young gave an impassioned speech about the need for no compromises go green with large cars that people like. On this, he is so all over it. Right now buyers are returning to the Escalade, Yukon and Denali in droves and you can't give a Prius away at all.
On November 9, in the early AM, the Linc Volt burned to the ground, taking a good bit of warehouse with it. It was definitely the car that started the fire. They are alluding to a "problem charging" with human error. The human error was having a BMS on it, and using it to control the charging of the car of course. Took the fire department most of an hour to get it out.
The car was truly beautiful. The message was beautiful. And Young was passionate about it. I'm crushed, and I never got to see the car and indeed Young and I have never met except by e-mail and phone. I can imagine how he feels about it. He CAN'T imagine how I do. Those dirty BMSs. You try rubbing them out and scrubbing them out, still everybody in the country is UNANIMOUS - you HAVE to have a BMS. They burn cars to the ground.
I've got some contacts in the battery scene. They provided me some shots from the SH2 battery trade show in Shenzhen China - including some shots of the new Gray cells that I'm now told will be available in February. The company naturally doesn't want to hurt current cell sales by announcing any of this before the switchover is announced. They also were showing a blue 200AH cell and a blue 210 AH cell that was very short but wide. I can't wait to get more information on these new batteries. I think this will be important.We have the motor and transmission back in the Mini Cooper. The new controller is mounted. And we've made some very interesting changes in the cooling and heating systems in the car - we've combined them into one. It can't possibly work. But I've kind of decided to start from the assumption that the controller and motor CAN heat the car, and the car CAN cool the motor and controller, and work backwards from there, adding components until it either does or doesn't. Should be interesting.
Jack Rickard
Monday, November 8, 2010
Itsy, Bitsy, Spyder 550 and Battery Balance Myths
In this week's episode, we assemble new mounts for the 2009 Mini Cooper Clubman drive train - somewhat colorfully.
We also wrap up our Vantage Green Van Battery Makeover. We have thrown out 775 lbs of AGM lead acid batteries and replaced them with 27 High-Power brand 200AH cells that I never liked well enough to put them in a car. The resulting pack weighs 350 lbs.
Because I had used some of the cells in some experiments in the lab, we were forced to bottom balance the pack, a three day adventure. Young Hauber subsequently drove the Vantage Green Van 103 miles on a single charge. This is a bit of an improvement over the 16 miles I had achieved during one test drive with the AGM's which only had 600 miles on them. Gentlemen. Lead is dead. Long live the LiFePo4. Get over it.
Also featured this week is Duane Ball's most excellent Spyder 550 build. And therein lies a tale.
Duane is about to take delivery of a Beck Porsche 904 from Special Editions Inc.
This is a fantastic new Beck reproduction. Just the roller will cost over $50,000. To raise funds for this project, Duane wanted to sell his beloved Spyder 550. So for a mere one Brazillion dollars, I bought it.
The car is a superb build with essentially duplicate components from Speedster Part Duh, but with a much better Brusa charger in it. Duane did use a PB-6 potentiometer box and a cable assembly to act as a throttle/accelerator, and everyone is pretty much unanimous that this was the one POS error in the car. It just feels awful. We'll be changing that.
In the meantime, the original Speedster is nearly 2 years old and has about 10,000 km on it. Duane's Spyder has 5811 km on it. So young Hauber and myself took advantage of a crisp, cool but beautiful October Sunday afternoon and drove on U.S. 61, a winding blacktop hilly highway to Perryville Missouri and back.
For some reason, this took more energy than it normally does. But to an interesting result. In the Speedster, we actually rolled to a stop just in front of our new shop at 601 Morgan Oak. We had to push the car inside by hand.
We had used a total of 195 AH out of the Speedsters two-year-old 180AH pack. And six cells were well under 0.5v STATIC once we pushed it inside and put a meter on it. This car has had NO BMS of any kind, other than a single CellLog8s misadventure for three days monitoring 8 cells and resulting in, you guessed it, a fire. It has been repeatedly run to full 100% DOD in testing. ANd we still managed 195AH from a 180AH pack (two strings of Thundersky TS-90AH in parallel).
So we've finally destroyed it. Well, at least we haven't done it any good. But as of last night, all cells were taking a charge and climbing in voltage. I'll check later today to see if any also LOSE their charge after the full charge. If they don't, this is incredible.
The Spyder 550 was also interesting. The cells are much easier to access, and we have young Hauber now to do the heavy lifting. It used 176 AH on the trip. It is much lighter (as is Hauber) accounting for the difference.
The Spyder is 1890 lbs with a 44% front and 56% rear weight distribution. As the cells were all still over 3.00v, I sent young Hauber for a couple of sleds of Stag Beer, his favorite housekeeping task here at EVTV. On return, the vehicle was showing 157 km total on the trip, 183.5 AH used, and a static voltage of just 95.65 volts or an average of 2.517 per cell.
After letting the cells rest and recover for a few minutes, I had Hauber take a reading of every cell in the car. Here's what we found....
Of course, the excellent news is that with NO BALANCE DONE EVER, and NO BMS EVER, a car with 5811 kilometers (3611 miles) on it was in excellent shape, excellent "balance" and all on the very vertical face of the discharge curve well below 3.00v and with 183 ah withdrawn from a 180 AH pack.
I have an odd ability at pattern recognition that is only occasionally useful for any thing. But the first 10 cells sort of jumped off the page at me. It raises a question.
The first 12 cells are arrayed across the front of the car, and so they may be getting dramatically more cooling than the cells in the rear of the car. But there are 12 of them. And cell 11 and 12 simply do not match the first 10.
I went to look at the overall pack voltage, and of course Duane had used a Xantrex. I recall the same problem on the Mini Cooper. I had originally used the lower 10 cells to power the Xantrex at the 35 volts it likes. Over time, this depletes the cells actually. The Xantrex doesn't draw much, but it draws enough. Duane had apparently used the first 10 cells, just as I had, and later went to a voltage divider across the entire pack to power the Xantrex, just as I had. It is eerie to see your MISTAKES replicated in somebody elses' build.
We put a charger on the 10 cells at about 30 amps for probably 5 minutes. They all fell right in line. And while we were doing it, with hit Cell 22 with a very brief shot to bring it up as well. I don't have a cogent theory for that one.
Here's what I DO get from all this. The "they gradually go out of balance" theory used to support the increasingly dubious case for the necessity of the BMS is just pure D Grade Bullshit. That is, bullshit that is not even very high grade bullshit. Here we have two cars that have NEVER been balanced in any direction, with a couple of years on one and 3600 miles on the other, where NONE of that has been done, and they both operate so well, that I can take 195 AH out of a 180AH pack apparently without mortal damage.
The BMS adherents, who increasingly start to look also like the BMS designers, who also look a lot like the people selling the BMS's are simply pumping BS for cash. Their products will actually DAMAGE your car, and the purported gain from using them is total nonsense. At this point, since we've made this information public numerous times, I believe that they KNOW or SHOULD HAVE KNOWN it was bullshit, and are actually lying to you for cash. There is no innocent "difference of opinion" going on here.
I have actually set out to cripple a perfectly operational electric car that I have well in excess of $70,000 invested in and have apparently FAILED to KILL IT. As I'm normally very good at these things, we'll see with some folow up tests that almost have to show some DAMAGE at least. But I could not kill the car, and did not drive any cells apparently into reversal.
If you top balance your cells, you CAN. And we have in the past done that empirically and publicly where anyone can duplicate the experiment.
ANd here is the problem with the online millieu, people have extended the right to "have their own opinion" to somehow include the right to have their own facts. It does not.
That said, they remain YOUR cells, do with them as you may.
The Rinehart controller we are installing in the Mini requires a switched ground signal to indicate the brake light is on. I don't quite get this. Brake lights run on 12v and you usually see 12v coming on when you apply the brakes. But it's easy enough to invert. A relay would work quite well, but we put on brakes a lot and so we're going to wear out the mechanical relay. Another way is simply to switch a transistor, which inverts the signal. A MOSFET is a good candidate because of very low forward resistance. We used a 75 Amp 30v MOSFET that is gross overkill to switch milliamps. But this will work quickly and probably won't ever wear out. This is the little diagram to invert our brake signal to a ground instead of 12v when we press the brakes. The 12v brake signal switches on the MOSFET applying ground to the output.
Jack Rickard
We also wrap up our Vantage Green Van Battery Makeover. We have thrown out 775 lbs of AGM lead acid batteries and replaced them with 27 High-Power brand 200AH cells that I never liked well enough to put them in a car. The resulting pack weighs 350 lbs.
Because I had used some of the cells in some experiments in the lab, we were forced to bottom balance the pack, a three day adventure. Young Hauber subsequently drove the Vantage Green Van 103 miles on a single charge. This is a bit of an improvement over the 16 miles I had achieved during one test drive with the AGM's which only had 600 miles on them. Gentlemen. Lead is dead. Long live the LiFePo4. Get over it.
Also featured this week is Duane Ball's most excellent Spyder 550 build. And therein lies a tale.
Duane is about to take delivery of a Beck Porsche 904 from Special Editions Inc.
This is a fantastic new Beck reproduction. Just the roller will cost over $50,000. To raise funds for this project, Duane wanted to sell his beloved Spyder 550. So for a mere one Brazillion dollars, I bought it.
The car is a superb build with essentially duplicate components from Speedster Part Duh, but with a much better Brusa charger in it. Duane did use a PB-6 potentiometer box and a cable assembly to act as a throttle/accelerator, and everyone is pretty much unanimous that this was the one POS error in the car. It just feels awful. We'll be changing that.
In the meantime, the original Speedster is nearly 2 years old and has about 10,000 km on it. Duane's Spyder has 5811 km on it. So young Hauber and myself took advantage of a crisp, cool but beautiful October Sunday afternoon and drove on U.S. 61, a winding blacktop hilly highway to Perryville Missouri and back.
For some reason, this took more energy than it normally does. But to an interesting result. In the Speedster, we actually rolled to a stop just in front of our new shop at 601 Morgan Oak. We had to push the car inside by hand.
We had used a total of 195 AH out of the Speedsters two-year-old 180AH pack. And six cells were well under 0.5v STATIC once we pushed it inside and put a meter on it. This car has had NO BMS of any kind, other than a single CellLog8s misadventure for three days monitoring 8 cells and resulting in, you guessed it, a fire. It has been repeatedly run to full 100% DOD in testing. ANd we still managed 195AH from a 180AH pack (two strings of Thundersky TS-90AH in parallel).
So we've finally destroyed it. Well, at least we haven't done it any good. But as of last night, all cells were taking a charge and climbing in voltage. I'll check later today to see if any also LOSE their charge after the full charge. If they don't, this is incredible.
The Spyder 550 was also interesting. The cells are much easier to access, and we have young Hauber now to do the heavy lifting. It used 176 AH on the trip. It is much lighter (as is Hauber) accounting for the difference.
The Spyder is 1890 lbs with a 44% front and 56% rear weight distribution. As the cells were all still over 3.00v, I sent young Hauber for a couple of sleds of Stag Beer, his favorite housekeeping task here at EVTV. On return, the vehicle was showing 157 km total on the trip, 183.5 AH used, and a static voltage of just 95.65 volts or an average of 2.517 per cell.
After letting the cells rest and recover for a few minutes, I had Hauber take a reading of every cell in the car. Here's what we found....
Of course, the excellent news is that with NO BALANCE DONE EVER, and NO BMS EVER, a car with 5811 kilometers (3611 miles) on it was in excellent shape, excellent "balance" and all on the very vertical face of the discharge curve well below 3.00v and with 183 ah withdrawn from a 180 AH pack.
I have an odd ability at pattern recognition that is only occasionally useful for any thing. But the first 10 cells sort of jumped off the page at me. It raises a question.
The first 12 cells are arrayed across the front of the car, and so they may be getting dramatically more cooling than the cells in the rear of the car. But there are 12 of them. And cell 11 and 12 simply do not match the first 10.
I went to look at the overall pack voltage, and of course Duane had used a Xantrex. I recall the same problem on the Mini Cooper. I had originally used the lower 10 cells to power the Xantrex at the 35 volts it likes. Over time, this depletes the cells actually. The Xantrex doesn't draw much, but it draws enough. Duane had apparently used the first 10 cells, just as I had, and later went to a voltage divider across the entire pack to power the Xantrex, just as I had. It is eerie to see your MISTAKES replicated in somebody elses' build.
We put a charger on the 10 cells at about 30 amps for probably 5 minutes. They all fell right in line. And while we were doing it, with hit Cell 22 with a very brief shot to bring it up as well. I don't have a cogent theory for that one.
Here's what I DO get from all this. The "they gradually go out of balance" theory used to support the increasingly dubious case for the necessity of the BMS is just pure D Grade Bullshit. That is, bullshit that is not even very high grade bullshit. Here we have two cars that have NEVER been balanced in any direction, with a couple of years on one and 3600 miles on the other, where NONE of that has been done, and they both operate so well, that I can take 195 AH out of a 180AH pack apparently without mortal damage.
The BMS adherents, who increasingly start to look also like the BMS designers, who also look a lot like the people selling the BMS's are simply pumping BS for cash. Their products will actually DAMAGE your car, and the purported gain from using them is total nonsense. At this point, since we've made this information public numerous times, I believe that they KNOW or SHOULD HAVE KNOWN it was bullshit, and are actually lying to you for cash. There is no innocent "difference of opinion" going on here.
I have actually set out to cripple a perfectly operational electric car that I have well in excess of $70,000 invested in and have apparently FAILED to KILL IT. As I'm normally very good at these things, we'll see with some folow up tests that almost have to show some DAMAGE at least. But I could not kill the car, and did not drive any cells apparently into reversal.
If you top balance your cells, you CAN. And we have in the past done that empirically and publicly where anyone can duplicate the experiment.
ANd here is the problem with the online millieu, people have extended the right to "have their own opinion" to somehow include the right to have their own facts. It does not.
That said, they remain YOUR cells, do with them as you may.
The Rinehart controller we are installing in the Mini requires a switched ground signal to indicate the brake light is on. I don't quite get this. Brake lights run on 12v and you usually see 12v coming on when you apply the brakes. But it's easy enough to invert. A relay would work quite well, but we put on brakes a lot and so we're going to wear out the mechanical relay. Another way is simply to switch a transistor, which inverts the signal. A MOSFET is a good candidate because of very low forward resistance. We used a 75 Amp 30v MOSFET that is gross overkill to switch milliamps. But this will work quickly and probably won't ever wear out. This is the little diagram to invert our brake signal to a ground instead of 12v when we press the brakes. The 12v brake signal switches on the MOSFET applying ground to the output.
Jack Rickard
Monday, November 1, 2010
The Perfect Storm
This week, we received a copy of a new JD Power and Associates study on the adoption of Hybrid and Battery Electric Vehicles. Note that they do make an appropriate distinction.
The Study is subtitled More Hope than Reality, and indeed it paints a bleak picture.
In my opinion, JD Power and Associates is one of the most prestigious survey firms in the world. NOT to be confused with the poseur think tanks funded by oil companies and automobile manufacturers. They live on customer satisfaction surveys and they're very good at getting right down to what's important.
The most important thing IN this study is some believable, and not so believable, numbers on total automobile production and operation.
Everyone is focused on peak oil and what it means. Peak oil is very real and I am very persuaded by such things as Deepwater Horizon's record setting operation in September 2009, before it was blown up in the Gulf oil spill disaster, to drill a hole 35,000 feet in the earth. Such a hole costs in excess of $200 million to drill. Somebody has got to want oil pretty badly. Surely there must be some closer to home. Apparently, to an increasing degree, not.
That's an indication that easy to obtain oil is not so easy to obtain, on the face of it. I don't have to know much about peak oil beyond the fact that they think they can, and need to, drill 35,000 feet to get at it profitably. I'm not one of those who decry oil companies and automobile manufacturers as somehow being stupid. I personally think they are VERY smart and have the very best people in the business, in the business. I don't particularly believe their interests are allied perfectly with MINE. But I do believe they will act in their OWN self interest pretty reliably and actually quite intelligently.
As to oil, what I got from this was basically that we produce 38% of the oil we use and China produces 46% of the oil they use. And the two countries make up the bulk of the automobiles in the world. They also have the lowest gasoline prices currently at $2.85 and $3.71 respectively. Everything in Europe is north of $6.00.
Oil is not precisely my focus, and not precisely the problem, as incredible as that statement may seem. It's cars. We have a lot of them. And we're making a lot more.
Any moron of sufficient age to remember, can remember what traffic was like, and what it is like now. Astute observation is not required to believe we have a lot MORE cars on the road. It's true we have a lot more people as well. But that almost doesn't account for it. We have a LOT more cars on the streets than we did 30 years ago.
It took a hundred years, give or take, to put the first 500 million cars on the road by 1995. It will take just 20 years to put the second 500 million on the road by 2015. At the end of 2010, we are looking at 896 million cars and we're manufacturing them at the rate of 44.7 million per year.
JD Power is looking out to 2020, ten years from now, and projecting an annual production of slightly more than 70 million cars with 1.2 billion in operation. That's a lot of cars. That's exponential growth in the number of cars.
It's true that many will be in India and China, along with a few Mercedes Benz from my friend in Dhubai. But wherever they are at and from wherever they issue, they are almost all going to burn gasoline.
I've said for years that the problem is not that gasoline is too expensive, but rather that it was too cheap. And had it been allowed to seek a natural level over time, the true costs of gasoline could have been gradually absorbed by our economy. We could have, for example, instituted more aggressive taxation of gasoline, since energy has ostensibly been a NATIONAL PRIORITY since Jimmy Carter. But we did nothing.
Simply putting a big tax on it now and using the funds to subsidize alternate energy is no longer an option. There isn't time. And it essentially is impractical. The cost of oil goes straight to the heart of the cost of transportation. Our global economy is founded on a historic move AWAY from local manufacture and consumption of EVERYTHING and toward global transportation of EVERYTHING and so the cost of EVERYTHING has a transport component built into it. NOt only the cost of everything, but of the cost of everything used to make everything. ANd so it is layer upon layer of transport costs. A sudden increase in those costs would be DEVASTATING to every economy on the globe.
And so there is no possibility, read NO possibility that the U.S. can lead the way on a cure. It's politically impossible. If you tried to enact a gasoline tax in this country at this time, it is NOT that you would be voted from office. You'd likely be assassinated. It would be UNLIKELY that you would live your elected term.
If we could, it would wreck our own economy on ANNOUNCEMENT and put us into a depression that made the 1930's look like a free lunch program.
And so we have before us the elements of THE PERFECT ENERGY STORM.
Less cars? Come on. In America we have had cars for a hundred years. They are almost everyone's most prized possession. We do not take trains and buses. We drive where we want to drive. Would you believe that now other people in other countries want the same thing. And why not? Personal mobility is a treasure. Everyone wants it universally. And it so constitutes at this point a basic human desire - to be neither ridiculed nor denied.
More oil? Where? How? The five largest corporations in the world with larger cash flows than most nations and the brightest people on the planet on that topic are doing everything they can and they're down to drilling seven miles into the earth looking for droplets.
We have oceans of natural gas, and yes, coal. And an enormous electrical distribution system. I already know the answer. But Americans aren't having any. I've mentioned REPEATEDLY that there is currently NO market for a compact car or mommy van as a battery electric vehicle.
According to JD Power, 61% of American consumers would now consider a hybrid vehicle. When advised that the difference in price might be $5000 on the initial cost of the car, that interest drops to 30%.
Battery electric vehicles are worse. Just 17% of American drivers would consider an electric vehicle with its limited range. When advised there is a $15,000 premium, that interest drops to 5%.
This isn't ORDERS. This is just INTEREST.
JD Power predicts an increase in Battery Electric Vehicles from just 20,100 vehicles in 2010 (including GEMs, vantage vans, etc.) to some 1.3 million by 2020. But 62% of those go to Europe. And 25% go to China. The U.S. will produce and use just 97,000 BEV vehicles for 7.5% of the world's electric cars.
In typical American fashion, as the perfect storm comes together and gasoline rises to $22 or $44 or $66 per gallon, there will be a LOT of interest in battery electric cars. They will be an overnight sensation. It won't matter. It will take years to produce them at that point. Too little. Too late. Another CNN emergency. But this time we don't get to cheer as the miners emerge or the oil spill is stopped. No magic bullet. No brilliant solution. Just misery and unemployment for millions who can no longer get around.
Technology has a standard S shaped adoption curve. ALL technology. First you have the tinkerers and innovators working with a technology that doesn't exactly work. It kind of sort of works just well enough to have an avid group of believers who keep dicking with it.
At some point, it gets good enough and you begin to see small businesses emerge to produce very expensive models that are a little awkward and clunky. Picture cell phones the size of a brick with its own suitcase that cost $3500 and feature a $1 per minute charge for calls that can only be made from six cities in the country.
At this point, the technology either fails and collapses, or gains ground. This is entirely a function of two things: human desire and early adopters. If the advantage of the new technology is sufficiently great that people DO want it even if they CAN'T afford it, it has a chance.
If for example, I told you I had a matter transporter that would safely transport a human from Los Angeles to New York city in 800 milliseconds, you would want it. If I told you it cost $26 million for a ride, you would STILL want it, but you could not afford it.
This is where early adopters come in. After the first ride, I can drop the price to $20 million. After the second ride, I can drop it to $10 million. After that it quickly drops to $1 million per ride and I'm doing a couple of rides per week. At $100,000, we're up to a couple of rides per day. At $10,000, thirty rides per day.
When it gets to a buck and a quarter everyone in Los Angeles is transporting to New York for dinner and back. The food's just better in New York.
Without those first early adopters, the transport machine gets disassembled and we'll use the parts to build an ice cream truck.
My take. Lead acid cells powered the early tinkerers and innovators with a technology that really just didn't work. RAV-4 and EV-1 included.
LiFePo4 changes the game. Electric cars can now be used as cars for most purposes. And it has attracted an early adopter set. Tesla is my poster child. At $150,000 for a roadster, it is expensive. But they have decoded what an early adopter might want and be willing to pay for in an electric car. Their Model S, which as you'll see in today's video is actually modeled after the Aston Martin Rapide, is frankly another very good move. Four passengers and luggage - much more practical as a car. But still very much an early adopter vehicle and probably priced in the seventy odd thousand range. I expect it to do VERY well.
But VERY well is relative. For a startup, who has sold 1500 vehicles total, what would a VERY well number look like. Five thousand would be a HUGE number by comparison. Ten thousand would be even grander. It would be a phenomenon.
What is the effect on the perfect storm? Well, ten thousand Tesla model S's if done well and show well would establish that the well heeled can drive an elegant sedan that does not run on gasoline. This is ATTRACTIVE. It appeals to HUMAN DESIRE. I can't afford one yet. But I WANT one. And because there are 10,000 of them, I can see one. I might even get to ride in one.
Let's contrast this with the Nissan Leaf. A compact mommy van that DOES offer the advantage of electric drive. It will NOT appeal to early adopters AT ALL.
It is intended to jump start this into the mass market. Will the mass market go for it? It's a one in a million shot.
Here's a compact car for $18,000. Here's a hybrid compact car for $23,000. Here's a Nissan Leaf, at $32,000. Ok, we'll subsidize it to $25,000. It's cool. It's electric. It also only goes 100 miles on a charge. Is this going to go?
There IS a fringe element of a few THOUSAND people who desperately want to go green and be cool and can't afford either. They spend most of their time whining about how OTHERS should spend their money on green, as a kind of annoying horsefly in the face hobby. I would expect them to buy the Nissan Leaf to finally scratch the itch. So they'll also sell 10,000.
The difference is that Nissan is a huge company gearing up to sell hundreds of thousands of these. Tesla is a startup without a chance who has thus far sold 1500 cars. 10,000 for Tesla is a huge win. 10,000 for Nissan is a HUGE loser. An enormous loser. The press will pick up on it and start parodying the "death of the electric car" again. They'll interview disatisfied stranded Leaf owners on camera.
One example greatly furthers the cause. The other example damages it extremely.
NEver mind GM trying to horn in with a 37 mpg hybrid that they insist is an electric car WHILE requiring gasoline in the tank to even start the vehicle. Understand that with a fully charged pack, you don't move without a tank of gasoline in a Volt. Not a foot. Interlocked.
The difference is the recognition of reality and where we are on the adoption curve for electric cars. Actually, there is an enormous opportunity here for any one of you with the guts to play. But it involves unique custom cars that are powerfully electric, done to the highest professional standards, and offered to interested early adopters that can afford them.
EVERY effort in that area assists the move up the S curve. Attempts to defeat or circumvent this curve actually can be harmful. And badly done hobby lead acid vehicles are a sure sign we're not ready for prime time.
Meanwhile, the forces converge with less and less oil, more and more cars, and a very loudly clicking clock....
In this episode, we talk about first impressions with the Rinehart Motion Systems AC inverter/controller that we are using to replace the TIMS600 in the 2009 Mini Cooper Clubman.
Our mini cooper tear down is very interesting. We found a LOT of interesting problems in this tear down that we didn't even know we had. The right side mount was torn, the clutch was burned, and most impressively the coupler shaft was actually twisted.
I'm trying to puzzle through the forces at play here. The most we could have conceivably applied in this car was about 365 amps at 335-340 volts. That cannot be over 125 kw or 167 hp. So how can we cause an engaged clutch disk to slip so badly it scorches the disk? And twist about a 5/8 inch 4045 tool steel machined shaft that is only two inches long?
The thing that has bitten me in electronics all my life is what I call the "time zone". Trons live in a different one than I do. I picture everything in people time. That's not where electrical devices live.
Let's take a 400 hp internal combustion engine. The 400 horsepower is at 3600 rpm, more or less depending on the engine. How long a time frame is required to step on the gas pedal and make 400 hp actually happen to the drive train? Well, the valve in the carburator has to physically open, more gasoline and air have to enter the chanber and vaporize, and that has to pump into the engine. With each detonation and valve action, a greater "gulp" of this mixture is achieved and the rpm rises. I would guess the "delay" from flooring the pedal to 400 hp would be 700 or 800 milliseconds unloaded, and actually through the drive train it could be a couple or three seconds.
Electric motors are different. RPM is different. First, higher RPMS means more cooling air. That's a good thing. At some point, higher RPM means increased counter electro motive force, decreasing torque - typically at 3500 rpm or so. But at instant ONE, if we put the pedal to the metal, the controller will ramp up the current into that motor very quickly. In theory, you coudl ramp this up in 6 to 10 milliseconds and have the full 167 HP applied to that shaft that quickly.
In actual practice, there are actually software mapping to RESTRICT how quickly that current output builds. I would urge yhou to take advantage of it. Because in electrical time zone terms, you can apply ALL the horsepower in a relative RIGHT NOW fashion. And the drive trains are NOT designed for that.
Yes, we're going to beef things up with a new stage 2 racing clutch and a much larger coupler. We're going to beef up our mountings. But with the Rinehart, we're also going to look for ways to slow down the action.
And this lesson will be particularly valuable in our ESCALADE PROJECT.
That's simply awaiting our Jim Husted twin 11 inch series DC motors. These are capable of instantaneous 320kw power applications - 428 hp. We think the retention of the TORQUE CONVERTER is key, not for torque multiplication, but to slow down the application of power. We're going to use SOliton1's very easy to use ability to map the current/second rampup quite conservatively as well. This, to prevent the Husted/Netgain motors from throwing my freakin transmission and rear end out through the tailgate and into oncoming traffic....
Don't think horsepower. Think horsepower per second. It matters....
Jack Rickard
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