Posts
We're having a time in the short days of winter. Here at the end of January, there is a bit of light at the end of the tunnel as the winter at this point WILL end at some point. But we struggle.
This week, we look at the final touches on the Electric Swallow. This is a neat little car with a neat little body and we had fun doing it. I was a little annoyed over the throttle issues but we more or less solved it with a 12v to 5 v converter even though it wasn't as it should be by the book.
We did do something we are going to try to incorporate in all future builds, including the Elescalade. That is interlock our controllers using the little relay on David Kerzel's J1772 board that we use. This little board is $37 and it makes your car respond to proximity switch and copilot signals from J1772 EVSE. But it features a little relay. On this build, we routed a 12v interlock signal through the normally closed contacts of this relay. In this way, if you plug in the charging plug, the car is disabled and you can't drive it away.
We actually routed the same signal through the Xantrex so it could also disable the controller when the SOC got down to 10%.
The car drove well and Lee took off for Denton with no real issues. If you stepped on the throttle all the way the controller kicked out. I showed him where to put a little resistor on the 5v DC-DC to fix that. And he seemed happy when he left Saturday afternoon. The car drives very nicely and as predicted, by using the 100Ah cells and the AC-50, it is very spritely.
We were hoping for additional reports when he got home on actual range and acceleration as we had no time for them here before he needed to be back to work.
Unfortunately, he apparently towed the car all the way to Denton with the VW tranny in gear. On arrival, he found transmission fluid all over the passenger compartment and nothing working. We're hopeful he can get all that turned around but it's a setback after all this work.
Meanwhile, I blew experimental A123 module La Troiseme number two WIDE OPEN.
I've already heard from a number of viewers DEMANDING to know what happened. Well, I'm not sure and I'm not sure we'll ever know. We don't have a "script" like House. Whatever happens happens and I don't always know what caused it.
Before casting, the cells measured 77.75 Ah which I thought was quite good. We cast it in resin and let it cure a few days and discharged it - but we really only got 65 Ah out of it and that was down to 24volts or 2 volts per cell. We probably over discharged a couple of cells at that point. Then we put the charger on it. After 80 Ah it never did reach above 41 volts but it DID split the resin wide open and the most positive set of cells were hugely swollen and leaking electrolyte. Later, another set split it in another place. So at least two cell segments failed.
No fire. No smoke. But some heat. And the module did split wide open.
Module one failed in an interesting way as a result of something I just did wrong. I've been playing with these new light object voltmeter controllers. They have a voltmeter that sports two relays with two voltage set points each. You can use these for all sorts of things.
I was using it to switch the first prototype Troiseme to a load. Of course the load is very low resistance. The cables to the load are also very low resistance. But we were sampling the voltage at the wrong place. So when the controller closed the contactor, the voltage dropped to under 2 volts because of the drop across the cables. The ratio of cable resistance to load resistance is very low. When it goes to 2 volts, the controller opens the contactor. With the load removed, the voltage shoots up above 3 volts. This causes the controller to close the contactor.
And so what I set up was a series of perhaps 50 cycles from zero to several hundred amperes all occurring in 30 seconds until I could figure out what was going on and get it stopped. This caused a lightning display inside the battery module. It now shows full voltage, but any attempt to draw the least amount of current results in a total collapse to zero volts - maximum internal resistance possible.
With Swallow finished,we are working more on the Elescalade and have good progress there really. Rod fabricated a couple of 3/8 inch polycarbonate covers for the massive 76 kWh battery pack and box in the back of the Cadillac. We've mounted an Manzanita PFC-75 to this cover and a Vicro Megapack power supply we will use with six 5v 40A modules and one 15v 10 Amp module for a 15 volt output at 90 amps for our 12volt system.
We also moved the Aurora Inverter down to the shop. This allows us to hook up the 192v pack to this inverter and drain about 36 amps from the pack to produce 21 or so amps of 240vac right into our panel. iN this way, we can use the truck to power the shop. Because of anti-islanding circuitry in the Aurora, this will do us NO good as far as backup power goes because it won't make any if we lose grid power. Why they have done this mindless thing makes no sense to me. It does not achieve the safety issue they sought.
But in any event, it DOES let us drain down a pack and instead of wasting the energy as heat, we can use it to run the bandsaw and the lights. That's pretty cool.
After taking the pack down to 170 volts, we'll trim from there manually using a little setup from the batt lab.
I basically mounted a 12v supply, a 0.1 ohm 250 watt resistor, a contactor, and this voltmeter controller all on a little piece of the aluminum aircraft decking we've been using. We have one set of cables to carry the 30 amps or so of drain current and a SECOND set of voltage sense wires with alligator clips we will connect DIRECTLY to the batt terminals to prevent the oscillation that caused so much trouble with the A123 module. In this way, we sense the actual battery voltage instead of the voltage after the current drop. Again, this is caused by the very low 0.1 ohm load. It's actually about the same amount of resistance as we see in the connections.
We'll set the lower limit at 2.60v and the upper limit at 2.77v. In this way, the cell will discharge into the resistor until it reaches 2.60v. At that point, the controller will disengage the contactor. The cell voltage will creep back up slowly. When it reaches 2.77v, the controller will again engage the contactor and take the cell down to 2.6v again. This cycle will be repeated until the cell just can't make it to 2.77v. That should be about 2.75volts near enough.
In this way, I can connect this device to each of the 57 cells in turn and basically walk away. An hour later, that cell should be at 2.75v. At some point, they all will be. Then we'll charge the pack and set our Manzanita for the top voltage.
The J1772 receptacle has some pretty stiff wiring but the 75 Amp Manzanita will certainly heat that up. Fortunately, it is just a foot or so long. We've terminated that in some terminals under the truck right where the J1772 comes in at the gas cap. We'll run 4 AWG cable from there to the Manzanita to handle the 75 amps this charge really can draw if you put it close enough to a panel. And of course, we have 4 AWG cables from the Manzanit to the cell terminals, although with the charger mounted on TOP of the battery box, those cables are quite short.
Again, we're going to use David Kerzel's little AC31 board to do the magic and make use of his relay to do a couple of things. Interlock the controller again of course. We'll also probably use it to turn on the heater pump through a seasonal switch. In this way, in winter with the seasonal switch set, the charger will cause the pump to come on circulating our glycol in the system. We're going to put two little 250 watt rubber heater pads on our system that run off of 240vac. When the J1772 connector is in, this will use wall AC to gently heat the system - all night long in most cases. So the pump will run and the very low level of heating should keep both cabin and batteries reasonably above freezing and I suspect, running all night, really quite warm which is why we are using such weenie heaters.
During the day while driving, our much larger 14 kw heater running off pack voltage can be used as desired. But I don't want THAT much heater running all night. A thermostat failure and we could really heat things up and cause a fire.
So we'll have an alternate system powered by AC when charging.
Today's video is of a bit more reasonable length. Our 3 hour mini series are just too much editing for me, and two much video for you.
Warmest Regards;
jack Rickard
Monday, January 30, 2012
Sunday, January 22, 2012
The International Module
We've built precisely two of the A123 modules of the third kind. I shouldn't be excited over something we don't REALLY know if it will work. And it IS risky. We've locked up 48 cells in urethane resin that can never be dug out again. If a single cell fails, we just tossed $1230 worth of cells out the window.
Of course, if a single foil fails in one of our normal prismatics, I suppose things start to go bad there as well.
So I'm thinking of it as a larger prismatic battery of 40volts and 75 Ah - car sized at 75 lbs.
The interesting thing is that it was designed by a landscaper from the North Coast of New South Wales, a battery guy from a small OEM in Lisbon Portugal, and neither of them have ever SEEN it before as the first assembly was in Cape Girardeau Missouri. ; And none of us even know each other beyond a brief introduction.
Michael Murray of New South Wales sent in the BLENDER animation we showed in last weeks episode. It was a direct embodiment of a connection scheme first described to us ny Celso Menaia of Lisbon. And we added a bit of aluminum as a heat sink and some Dascar Plastics RP-40 urethane casting resin. Actually about a gallon for each battery.
I confess my heart was NOT in the module project initially. But something about the A123 cells kept nagging at me. Often, I know something is important by looking at it, but for some time I cannot come up with just WHY I know it is important, or important in what way. In that situation, I just keep fooling with it and at some point it will tell me.
What this does is open the door to smaller, lighter, cheaper battery packs for smaller, lighter, cheaper electric cars. And why is that important to someone building a $160,000 Cadillac Escalade Project? Well, there are a lot of viewers who are not going to build an Escalade. That's reality.
And we hear from a lot of viewers that are definitely going to build SOMETHING ,but seem stuck in "PARK" awaiting the signal to go.
We have been dismissive of lead acid cars as being "Science Projects" but in reality, that level of expenditure seems doable for most people, while the $17,500 required to do it our way does not.
I've been curiously unsympathetic. An aluminum john boat on a trailer with a trolling motor runs over $18,000 new now. So I remain curiously unsympathetic. My heroes, the real pioneers, routinely put down two or three times that for a build and are moving the token forward to change the world.
But it is of course true that all of this happens faster at a lower price.
So let's change the game. And that requires some different assumptions.
Let's talk about range. The lead guys swear they get 40 to 50 miles on a charge. This is where I fault them first. It's a barefaced lie. They do not.
They might get it in theory, but in reality, 30 or 35 miles might be the range of their FIRST test drive. ANd it goes down steadily from there to five or six miles two years later when they park it.
If we defined our battery as 120v and 75 Ah for 9000 wH, and 225 lbs, we could probably do 35-50 miles on a single charge REALLY. We would be a half TON lighter than lead. Instead of a two year life, we have potentially a 10 year life.
I believe you could build these modules for around $1400 each. Three would be $4200, which is very different from $8500 or $10,000.
And do you know what? Not only is range anxiety not an issue for me at 80 miles or 100 miles, but my wife has been driving a car with a 45 mile range for months now and it hasn't been a problem yet. We charge more often, but she really does NOT drive more than 45 miles per day.
The trick is the power output. The A123 cells we have TESTED to 23C - that is they made 475 amps in front of me while I was watching - from a series of three single cells. Yowsers.
ANd that means that despite it being a weenie 9000 wH pack, it could put out 1850 amps or so. Which is nearly TWICE what a Soliton1 will do and over THREE TIMES what the Curtis 1238-7601 can do. So we get not only FULL performance and FULL acceleration, but with a 225 lb pack, I would say OVER full acceleration.
Better, if you build a car this way, with this modest "test pack" in it and it all works out for you, but you need more range, what level of effort do you imagine you would face in wiring in three more of these? Picture a single Saturday afternoon.
So we think demonstrating this might just open up the EV project concept to a LOT of people that are avidly watching our show, but not actually turning a wrench at the moment.
This egregiously long and boring episode shows you how. We omitted the resin casting at the end, which is no big thing and we can cover it next week. But all the important and hard parts are there. It is a good bit of work. They do not assemble themselves. But we think it is a good design. Testing will tell. Note A123's own module is in recall as we speak. These things aren't easy. ANd I'm really NOT a packaging engineer.
We're also a little giddy with cash flow these days. In the past week, we've sold over a dozen sets of the battery strap kits. This is simply a 70mm braided strap for a CALB 100 or 180Ah cell, a Thundersky 160 Ah cell or SOME Thundersky 100 Ah cells. We also throw in two stainless M8 bolts and two zinc coated Nordlock washers - the combination that has worked SO very well for us in the past year or so. We mentioned we'd sell these at $7 each and we've moved about 1000 straps in the first week.
This is no big deal. It's a small thing. But God is in the details. Battery connections are a quick way to a stranded car. And we've kind of worked out over time how to simply avoid that entirely. We were getting straps from Australia, and now we have to get them in a relatively huge quantity from China in order to have them. But we think they're a huge improvement over the copper straps provided with the cells.
This is the longest show we've ever done. As Mark Twain said, I would have written a shorter letter, but I hadn't the time.
The close ups and the green chroma key have strained our editing equipment and software to the very limtis of what they can do.
Regards;
Jack Rickard
Of course, if a single foil fails in one of our normal prismatics, I suppose things start to go bad there as well.
So I'm thinking of it as a larger prismatic battery of 40volts and 75 Ah - car sized at 75 lbs.
The interesting thing is that it was designed by a landscaper from the North Coast of New South Wales, a battery guy from a small OEM in Lisbon Portugal, and neither of them have ever SEEN it before as the first assembly was in Cape Girardeau Missouri. ; And none of us even know each other beyond a brief introduction.
Michael Murray of New South Wales sent in the BLENDER animation we showed in last weeks episode. It was a direct embodiment of a connection scheme first described to us ny Celso Menaia of Lisbon. And we added a bit of aluminum as a heat sink and some Dascar Plastics RP-40 urethane casting resin. Actually about a gallon for each battery.
I confess my heart was NOT in the module project initially. But something about the A123 cells kept nagging at me. Often, I know something is important by looking at it, but for some time I cannot come up with just WHY I know it is important, or important in what way. In that situation, I just keep fooling with it and at some point it will tell me.
What this does is open the door to smaller, lighter, cheaper battery packs for smaller, lighter, cheaper electric cars. And why is that important to someone building a $160,000 Cadillac Escalade Project? Well, there are a lot of viewers who are not going to build an Escalade. That's reality.
And we hear from a lot of viewers that are definitely going to build SOMETHING ,but seem stuck in "PARK" awaiting the signal to go.
We have been dismissive of lead acid cars as being "Science Projects" but in reality, that level of expenditure seems doable for most people, while the $17,500 required to do it our way does not.
I've been curiously unsympathetic. An aluminum john boat on a trailer with a trolling motor runs over $18,000 new now. So I remain curiously unsympathetic. My heroes, the real pioneers, routinely put down two or three times that for a build and are moving the token forward to change the world.
But it is of course true that all of this happens faster at a lower price.
So let's change the game. And that requires some different assumptions.
Let's talk about range. The lead guys swear they get 40 to 50 miles on a charge. This is where I fault them first. It's a barefaced lie. They do not.
They might get it in theory, but in reality, 30 or 35 miles might be the range of their FIRST test drive. ANd it goes down steadily from there to five or six miles two years later when they park it.
If we defined our battery as 120v and 75 Ah for 9000 wH, and 225 lbs, we could probably do 35-50 miles on a single charge REALLY. We would be a half TON lighter than lead. Instead of a two year life, we have potentially a 10 year life.
I believe you could build these modules for around $1400 each. Three would be $4200, which is very different from $8500 or $10,000.
And do you know what? Not only is range anxiety not an issue for me at 80 miles or 100 miles, but my wife has been driving a car with a 45 mile range for months now and it hasn't been a problem yet. We charge more often, but she really does NOT drive more than 45 miles per day.
The trick is the power output. The A123 cells we have TESTED to 23C - that is they made 475 amps in front of me while I was watching - from a series of three single cells. Yowsers.
ANd that means that despite it being a weenie 9000 wH pack, it could put out 1850 amps or so. Which is nearly TWICE what a Soliton1 will do and over THREE TIMES what the Curtis 1238-7601 can do. So we get not only FULL performance and FULL acceleration, but with a 225 lb pack, I would say OVER full acceleration.
Better, if you build a car this way, with this modest "test pack" in it and it all works out for you, but you need more range, what level of effort do you imagine you would face in wiring in three more of these? Picture a single Saturday afternoon.
So we think demonstrating this might just open up the EV project concept to a LOT of people that are avidly watching our show, but not actually turning a wrench at the moment.
This egregiously long and boring episode shows you how. We omitted the resin casting at the end, which is no big thing and we can cover it next week. But all the important and hard parts are there. It is a good bit of work. They do not assemble themselves. But we think it is a good design. Testing will tell. Note A123's own module is in recall as we speak. These things aren't easy. ANd I'm really NOT a packaging engineer.
We're also a little giddy with cash flow these days. In the past week, we've sold over a dozen sets of the battery strap kits. This is simply a 70mm braided strap for a CALB 100 or 180Ah cell, a Thundersky 160 Ah cell or SOME Thundersky 100 Ah cells. We also throw in two stainless M8 bolts and two zinc coated Nordlock washers - the combination that has worked SO very well for us in the past year or so. We mentioned we'd sell these at $7 each and we've moved about 1000 straps in the first week.
This is no big deal. It's a small thing. But God is in the details. Battery connections are a quick way to a stranded car. And we've kind of worked out over time how to simply avoid that entirely. We were getting straps from Australia, and now we have to get them in a relatively huge quantity from China in order to have them. But we think they're a huge improvement over the copper straps provided with the cells.
This is the longest show we've ever done. As Mark Twain said, I would have written a shorter letter, but I hadn't the time.
The close ups and the green chroma key have strained our editing equipment and software to the very limtis of what they can do.
Regards;
Jack Rickard
Tuesday, January 17, 2012
Braided Copper Ground Straps.
Over the past three years we've paid careful attention to our battery connections. There's a reason. Even in the days of lead acid Trojans, it was not unusual to blow the entire CORNER of your battery case off with an almost explosive event over a battery connection.
These aren't terribly dangerous. But they're not very convenient either. Kind of like a rifle shot going off behind your ear. And you are stranded. Of course, you also lose the expensive battery.
So we mind our connections. I really rather liked the little bent copper straps we got with our first few sets of cells. And the steel M8 bolts and lockwashers were a HUGE improvement over the slotted soft aluminum screws we got with our first set of Seiden LiFePo4 cells.
And they worked well enough. But there were some disadvantages that just kept growing on us. The most worrisome is the lock washers. The threaded holes in the cells ARE soft copper and aluminum. The M8 size and 1.25 mm thread are really a pretty strong size in that soft material. But you cannot overtighten these or you will strip them and have to retap with a larger tap and use a larger bolt.
More to the point, however you tighten them, if you check back in a month, they have all loosened up an 1/8 turn. Some a 1/4. Not good. As they loosen, resistance starts to build, corrosion occurs, and at some point you blow a connection from current flow. And quite possibly a cell this way.
The problem is that a car vibrates going down the road. Worse, the bolt, wssher, strap, and terminal are all different metals with different thermal expansion coefficients. And every time we press the accelerator, we heat them up. ANd every time we release the accelerator, we cool them down. Constant thermal cycling and constant vibration combine to gradually work even very good connections loose.
The other area of concern is current inflation. By that, I mean that three years ago 300 amps was quite a bit of current. Then 500 amps. Then 1000 amps. Now with teh Cobra, we're doing 1200 and 1300 amps routinely. Now with the Escalaade, we're talking about 2000 amps - or was it 3000 amps.
Those little bent copper straps are good up to a point. But in China, an electric car with a 10 kw motor is motoring. Here, we're starting to look at 150 kw, 200kw and in teh case of the Elescalade, 400kw power plants. That's a lot higher current than we were dealing with just a year or two ago.
Over time, we've come up with a terminal connection scheme that has worked EXTREVELY well for us. We no longer HAVE loose connections AT ALL. We can handle a lot higher currents. We no longer are "prying" against the terminal with every flex of our battery pack. The whole pack is "flatter" and in fact looks a lot better. So what did we do?
1. Braided copper grounding straps as straps. These are copper of 50 sq.mm cross section. But it is tinned to reduce corrosion and increase connectivity at the terminal surface. They flex in the BRAID. So the encased part at each end is held flat to the terminal. As the pack flexes, the braid takes up the flex. There is just more copper in these too so they can carry more current.
2. A little upgrade on the bolts to 18-8 stainless steel.
3. Nordlock Washers. http://www.nordlock.com. This Swedish company has invented a wedgelock washer that is very hard, and features a kind of reverse CAM between the two active pieces. Each piece bites into the adjoining hardware to grip it, and then to LOOSEN the bolt, you have to work against the cam direction between the two washers. This actually INCREASES pressure on the bolt. They just don't back out. Not from thermal cycling. Not from vibration. They are ORDERS OF MAGNITUDE better at keeping those connections clean and tight than the lockwashers we are so accustomed to.
4. Zinc coating on Nordlock washers. In a situation of dissimilar metals, in the presence of an electrolyte, you get a bit of galvanic action that causes corrosion. This can be diminished using a bit of Zinc as a "sacrificial anode" to give up electrons. So we use the Zinc coated Nordlocks.
We were getting our braided straps from EVWorks in Australia. This has been an excellent source of a number of components for us over the years. They appear to be currently undergoing some changes internally. We're not sure what all that's about. But we recently ordered some straps for our 400 Ah cells and received the wrong ones. Their response was bizarre. They've offered to change the text on their web site. And they don't have any for our 400 Ah cells and won't EVER have any.
Worse, they have recently had some new shipping deal that sent the cost of these way over $5 a piece by the time they hit the U.S.
So we had to cast about China to find a source for braided tinned copper ground straps.
We found one. And they made us stome straps for our 400 Ah cells. The problem is, they like to sell them in quantities of ONE BRAZILLIAN at a time. Now we are never going to need a brazillian 400a cell straps. But we do use quite a few of the straps for 180Ah and 160 Ah and 100 Ah cells from CALB and Thundersky. These are 98 mm long with 8mm x 13mm holes on 70 mm centers. So we talked them into making us a couple of hundred 400Ah straps if we ordered ONE BRAZILLIAN 70 mm x 8 mm straps.
They agreed. And four or five THOUSAAND dollars later, we have our straps and a lifetime supply of 70mm straps as well. And we love them.
We mentioned this on the show, and had three immediate sales of EVTV viewers who have builds going who needed small quantities of these straps. So we put together a little kit with a strap, two of the 18-8 stainless bolts, and two of the Nordlock washers - for $7 plus shipping. Our first three sets averaged about $30 for a $2 box and the UPS ground charges. Way different from shipping from Australia or China.
So we're going to offer these sets complete with the two bolts, two washers, and one strap at $7. You don't have to chase all this down the way we have had to. And you'll enjoy clean, tight, safe high current connections that actually make your pack look good as well.
This is one way to support EVTV and help us reduce the inventory on hand of ONE BRAZILLIAN 70mm braided copper straps.
There are also straps with holes on 60mm and 80 mm centers - the 8 mm holes of course. We can get those as well if anyone needs them.
Send me an email to jack@evtv.me with the number you want and your shipping address. I'll respond with a Paypal invoice with the shipping calculated - but usually $25-$30 here in the U.S. Each "set" weighs 0.19 lbs if you are into calculating such things.
Regards;
Jack Rickard
These aren't terribly dangerous. But they're not very convenient either. Kind of like a rifle shot going off behind your ear. And you are stranded. Of course, you also lose the expensive battery.
So we mind our connections. I really rather liked the little bent copper straps we got with our first few sets of cells. And the steel M8 bolts and lockwashers were a HUGE improvement over the slotted soft aluminum screws we got with our first set of Seiden LiFePo4 cells.
And they worked well enough. But there were some disadvantages that just kept growing on us. The most worrisome is the lock washers. The threaded holes in the cells ARE soft copper and aluminum. The M8 size and 1.25 mm thread are really a pretty strong size in that soft material. But you cannot overtighten these or you will strip them and have to retap with a larger tap and use a larger bolt.
More to the point, however you tighten them, if you check back in a month, they have all loosened up an 1/8 turn. Some a 1/4. Not good. As they loosen, resistance starts to build, corrosion occurs, and at some point you blow a connection from current flow. And quite possibly a cell this way.
The problem is that a car vibrates going down the road. Worse, the bolt, wssher, strap, and terminal are all different metals with different thermal expansion coefficients. And every time we press the accelerator, we heat them up. ANd every time we release the accelerator, we cool them down. Constant thermal cycling and constant vibration combine to gradually work even very good connections loose.
The other area of concern is current inflation. By that, I mean that three years ago 300 amps was quite a bit of current. Then 500 amps. Then 1000 amps. Now with teh Cobra, we're doing 1200 and 1300 amps routinely. Now with the Escalaade, we're talking about 2000 amps - or was it 3000 amps.
Those little bent copper straps are good up to a point. But in China, an electric car with a 10 kw motor is motoring. Here, we're starting to look at 150 kw, 200kw and in teh case of the Elescalade, 400kw power plants. That's a lot higher current than we were dealing with just a year or two ago.
Over time, we've come up with a terminal connection scheme that has worked EXTREVELY well for us. We no longer HAVE loose connections AT ALL. We can handle a lot higher currents. We no longer are "prying" against the terminal with every flex of our battery pack. The whole pack is "flatter" and in fact looks a lot better. So what did we do?
1. Braided copper grounding straps as straps. These are copper of 50 sq.mm cross section. But it is tinned to reduce corrosion and increase connectivity at the terminal surface. They flex in the BRAID. So the encased part at each end is held flat to the terminal. As the pack flexes, the braid takes up the flex. There is just more copper in these too so they can carry more current.
2. A little upgrade on the bolts to 18-8 stainless steel.
3. Nordlock Washers. http://www.nordlock.com. This Swedish company has invented a wedgelock washer that is very hard, and features a kind of reverse CAM between the two active pieces. Each piece bites into the adjoining hardware to grip it, and then to LOOSEN the bolt, you have to work against the cam direction between the two washers. This actually INCREASES pressure on the bolt. They just don't back out. Not from thermal cycling. Not from vibration. They are ORDERS OF MAGNITUDE better at keeping those connections clean and tight than the lockwashers we are so accustomed to.
4. Zinc coating on Nordlock washers. In a situation of dissimilar metals, in the presence of an electrolyte, you get a bit of galvanic action that causes corrosion. This can be diminished using a bit of Zinc as a "sacrificial anode" to give up electrons. So we use the Zinc coated Nordlocks.
We were getting our braided straps from EVWorks in Australia. This has been an excellent source of a number of components for us over the years. They appear to be currently undergoing some changes internally. We're not sure what all that's about. But we recently ordered some straps for our 400 Ah cells and received the wrong ones. Their response was bizarre. They've offered to change the text on their web site. And they don't have any for our 400 Ah cells and won't EVER have any.
Worse, they have recently had some new shipping deal that sent the cost of these way over $5 a piece by the time they hit the U.S.
So we had to cast about China to find a source for braided tinned copper ground straps.
We found one. And they made us stome straps for our 400 Ah cells. The problem is, they like to sell them in quantities of ONE BRAZILLIAN at a time. Now we are never going to need a brazillian 400a cell straps. But we do use quite a few of the straps for 180Ah and 160 Ah and 100 Ah cells from CALB and Thundersky. These are 98 mm long with 8mm x 13mm holes on 70 mm centers. So we talked them into making us a couple of hundred 400Ah straps if we ordered ONE BRAZILLIAN 70 mm x 8 mm straps.
They agreed. And four or five THOUSAAND dollars later, we have our straps and a lifetime supply of 70mm straps as well. And we love them.
We mentioned this on the show, and had three immediate sales of EVTV viewers who have builds going who needed small quantities of these straps. So we put together a little kit with a strap, two of the 18-8 stainless bolts, and two of the Nordlock washers - for $7 plus shipping. Our first three sets averaged about $30 for a $2 box and the UPS ground charges. Way different from shipping from Australia or China.
So we're going to offer these sets complete with the two bolts, two washers, and one strap at $7. You don't have to chase all this down the way we have had to. And you'll enjoy clean, tight, safe high current connections that actually make your pack look good as well.
This is one way to support EVTV and help us reduce the inventory on hand of ONE BRAZILLIAN 70mm braided copper straps.
There are also straps with holes on 60mm and 80 mm centers - the 8 mm holes of course. We can get those as well if anyone needs them.
Send me an email to jack@evtv.me with the number you want and your shipping address. I'll respond with a Paypal invoice with the shipping calculated - but usually $25-$30 here in the U.S. Each "set" weighs 0.19 lbs if you are into calculating such things.
Regards;
Jack Rickard
Monday, January 16, 2012
We've Gone Green
To an optomist, the glass of water is half full. To a pessimist, it's half empty. Kind of a point of view thing. Of course, to an engineer, we have a curious instance of a water glass that's probably twice the necessary size, and undoubtedly mounted in the wrong place anyway. And is there any REAL necessity for it to be constructed of expensive and failure prone glass. ABS plastic would likely contain the water as well, within certain temperature constraints.
This week we DO indeed present for your edification, education, consideration, and approval, one each MILSPEC video, color green.
We had failed in the previous week to do so. And I suppose we should explain, though I'm not certain why there is such a necessity to do so. There is no program or plan here. We simply reached a Friday and had nothing to say.
We also had nothing done. I've been spending a stupid amount of time playing with something I'm not very good at in the first place, physical machining and packaging for these A123 cells. That causes me to rush a bit on the bits I SHOULD be doing and as a result, I've actually blown up a bunch of test equipment. I don't know if these were run of the mill failures or my failures in every case, but I've lost a couple of loads and a power supply in a week.
Throughout the week we work on various little things and either shoot pieces as we go along, or get them all set up to shoot quickly on Thursday and Friday. By Friday afternoon, we had NOTHING - everything we had tried to put together either had some weird failure with no explanation or we were waiting on a part, a vendor to explain why, or something similar. We went down the list Friday afternoon and all had incurable delays or halts to everything we had had a notion of doing that week.
So I went home. Had a lovely evening playing bridge and drinking wine with some friends of ours until quite late. And awoke Saturday morning with no video to edit. Nothing more complicated than that.
I must confess, that in recent weeks I've been a bit removed from our overall process and there are few cues in the shop that anyone is watching anyway. My e-mail load had dried up over the holidays as people, I guess, were enjoying the holiday. And I was feeling a little bit of end of year reflection on why we are doing this, what we are accomplishing with it, and whether it is really worth a 24x7 365 day effort. After all, I do have electric cars to drive at this point. What's the emergency, what are we REALLY accomplishing here, and why am I working this hard at age 56. Truth to tell, we're probably leading this industry by a full two years from where I had thought/hoped we were.
I know that is a bit hard to accept with daily announcements of OEM electric car offerings literally pouring from the screen. Hasn't the electric car revolution already happened and we are just mopping up the last of the late adopters and conservative majority on this one?
I fear not. More like we don't have the early tinkerers and innovators sufficiently and properly organized to sponsor an outdoor cookout even WITH the assistance of the Boy Scouts of America (BSA). I'm actually a bit discouraged that we have been unable to move that token any further than it currently lies on the ground.
In any event, it's the end of the year. I think I'm going to slow down the pace and play with what strikes me. This week it is the simple addition of an experiment with green chroma key. I was all wired up for a prolonged battle with Final Cut Pro X over green chroma key. We got a largish piece of green muslin and a frame to drape it over behind us and shot the show on faith with nothing to look at.
There were a couple of tricks but really within an hour on Saturday morning I had figured out pretty much how it worked. And lo and behold, Brain and I could be ANYWHERE in front of ANYTHING with the flick of a mouse. I know this is a very basic technique to any of you advanced video professionals. But to us country boys trying to make our way in the big city, this is astonishing. And to have a weather map that is really a schematic diagram is pretty cool for some of these discussions. Without a schematic, my talking doesn't really make any sense at all.
I have also been hard at work on TWO different A123 modules. The first, actually described to me by Kevin Wong worked quite well actually. It had a couple of minor problems but was very easy to assemble. Unfortuantely, there's no point in showing it as we've already moved on.
The second was originally described somewhat vaguely by Celso Menai of Portugal. Celso IS kind of the battery guy with a small OEM that is developing a kind of tricycle car that is really quite captivating in the video he showed us at EVCCON. This theme was expanded by Mic of Oz - an Australian who provided an animation of it on Vimeo that I rather liked.
Actually in the time I SHOULD have been making video, I've made this module THREE TIMES in prototype form. The last has some 48 cells in a 4P12S configuration for a 40 volt 75 Ah module. It is 19.75 inches long, about eight inches high and about nine inches wide and weighs about 75 lbs. It represents a 3 kWh pack.
The prototype has spaghetti wiring on it for the Cellog 8S modules to monitor individual cell voltages. We bottom balanced the entire set of cells at 2.75 volts during assembly. We'll be charging it and discharging it to see what happens to the individual cells. Under load, poor connections and so forth show up.
This is kind of a leap of faith. We used nylon threaded rod and some pvc nuts and by following Mic's instructions and including a nut with every insulated piece, we think we've managed the clamping forces as well as they can be managed. But we do not want flexing between the tabs and the spacers in the vibrating environment of a vehicle. So we've cast the ENTIRE thing in the urethane resin we've been playing with.
Actually for the prototype, we have the opaque resin in the bottom and some nearly clear resin in the top and we want to see where we are. But the thing winds up looking like a 75 lb block of ice with spaghetti wiring out the top.
A123 is of course having their own problems with their over engineered cooling system. We did something quite different. I procured some thin 0.30 aluminum sheet from our ONLINE METALS supplier done in gunmetal anodize. Anodized aluminum is kind of peculiar in that it really doesn't conduct electricity very well, but it DOES conduct heat. So we made little panels of it with a 90 degree bend at the bottom just wide enough for two cells. We slipped those between each TWO cells with the leg pointing IN toward the center.
When we put the battery in the resin form, we pulled the panels down slightly to where the feet touched the form box ends. Then we poured the resin.
We'll wire brush the resin off these thin feet, exposing the aluminum.
In this way, each cell makes contact with a full sized plate of thin aluminum. That plate extends to the END of the battery where it hooks into this 1/2 inch foot spanning the height of the assembly. I do hope this wicked any heat from any of the cells to these exposed feet. At that point, for some applications this will be adequate. But you COULD attach a chill plate, a finned heat sink, or just place the battery in an aluminum box with contact at the ends between the feet and the box.
The resin, once hardened, should effectively isolate the clamps and tabs and cells and panels from rubbing, chafing, loosening, and otherwise wearing. This is what I consider and important and unfortunate part of the design. We no longer have discrete cells to work with here and no real access to them (other than the spaghetti on the prototype).
I'm actually ok with this. We don't have access to individual foils in the CALB prismatics we use. So not having access to individual A123 cells is not so very different, except that we have some in SERIES in this battery making up a 40 volt module.
Note also the lack of BMS. I intend to use these as true batteries. If they go bad, they go away. By bottom balancing them on assembly, I'm hoping to prevent failures. : But a single bad cell in this bunch means inevitable and almost immediate failure. We should really capacity test these as well before assembly.
I've ordered a little voltmeter with programmable relay from ColdFusion. I intend to hook this up to a contactor and load situation where I can connect a cell and walk away. When it gets down to a specific voltage, ti will disconnect the cell from the load. Assuming they arrive at nearly identical state of charge, this should take them down to an identical state of low charge. I should be able to read our AH meter to detect "short" cells. And the resulting cells can be combined into an already bottom balanced assembly this way with a pretty good confidence on the capacity as well.
Three such batteries would be a 120volt 75 AH assembly and would drive one of the HPEVS systems very nicely with 9000 wH of storage in a scant 225lbs of batteries. We think this would be a 40-50 mile total range or maybe 32-35 mile range at 80% DOD. That's not far, but many people do drive less than that each day, including yours truly and frankly. The bare cell costs, delivered to us circa 1/1/12, look like about $1250 per module or $3750 for the pack. With resin, threaded rods, hardware, etc, you might be looking at a round $1500 per module or $4500.
Why is this important? Well, lead acid batteries reportedly cost $2500 and offer a 40 mile range. We happen to know that delivered to your driveway, they are more often $3000 unless you are near a battery store where you can get a deal and pick them up yourself. And the 40 mile range is almost entirely made up - wishful thinking. Lead cell cars usually get 25-30 miles in the first two months, and then it drops horrifically over the remaining two years of life. And they weigh a 1000 lbs.
Three of these modules weigh 225 lbs. They really will do 40 miles. They have the advantage of long cycle life - over 3000 cycles. And 650 amps is nothing for these cells. Our tests indicate about an 1850 ampere power output from this module.
So instead of $10,000 for batteries, you pay a 50% premium over lead, and get the same range (actually better) , MUCH lighter weight, and much longer life. If you WANTED to add more cells later in parallel to double the range, it is trivial to do so.
We did order and receive some excellent braided straps from China to replace our EVWorks source in Australia. The shipping and duties from Australia had become really quite onerous and our final cost per strap was over $5 via this avenue in all cases and in the case of the 55 mm straps considerably so.
The shipping and so forth from China is actually pretty steep as well, I think our UPS was $686 on this batch and then UPS came up with some strange $131 brokers fee on the import of these. In any event, I got 1000 of the 70 mm straps we always use on the 100 and 180Ah CALB cells. And a couple of hundred of the straps for the larger M12 bolts on the Elescalade.
We mentioned that it looked like that put us in the strap business whether on purpose or by accident. THree of our viewers have ordered in the first twelve hours so I guess this will be worthwhile. We're going to put together a set of one 70mm strap, two 18-8 stainless 16 mm M8 bolts, and two zinc coated M8 Nordlock washers for $7 plus shipping. We'll work on getting some sort of page up that calculates shipping and totals and so forth to make it easy. The larger set for the 400 Ah cells would be $10 per set, but I would be astonished if anyone but us needs those at all.
What I call 70mm straps have 8x13mm holes on 70mm centers. The strap is actually 98 mm long and 24 mm wide of tinned copper braided wire with tinned copper on the ends. We'll put some photos on the web page when we get it up.
In the meantime, all of you that did send e-mail and Paypal donations this past week, fearing our demise, we deeply appreciate them. It IS true enough that if we don't find some economic basis for doing this, it cannot continue forever. But that's not precisely why we missed a week now. But operating with Brian and I and Rod in a dark shop in the cold of winter, we kind of lose sight that anyone is watching or that anyone cares. There's no shortage of video on YouTube we are well aware. And so our confidence in our mission naturally wanes. The encouragement is actually as important or more important than the donations, but encouragement in DECIMAL is of course the most sincere. I only contribute actual ducats when I actually want to support something. It's not just happy talk. And we assume you all do the same. So I was encouraged this week. Our viewership appears to be growing and we appear to have the requisite "stickiness" among a set of viewers that keep coming back. That means eventual success if we simply persevere.
We're hardly alone in our struggles. George Hamstra has 100 motors with no aux shaft as the result of an OEM failure (I'm telling you selling to OEMs is not all as great as you think guys) and Sebastien Bourgoius reports costs on the Shiva have driven them to an atmospheric $9500 for their megawatt controller. So everyone is having their version of a bad hair day at the moment.
But stay with us. If this thing with Iran doesn't get resolved here pretty soon, we could ALL be heading for a bad hair day at the pump. And we're just not sufficiently far enough along with all this to deal with it.
Jack Rickard
This week we DO indeed present for your edification, education, consideration, and approval, one each MILSPEC video, color green.
We had failed in the previous week to do so. And I suppose we should explain, though I'm not certain why there is such a necessity to do so. There is no program or plan here. We simply reached a Friday and had nothing to say.
We also had nothing done. I've been spending a stupid amount of time playing with something I'm not very good at in the first place, physical machining and packaging for these A123 cells. That causes me to rush a bit on the bits I SHOULD be doing and as a result, I've actually blown up a bunch of test equipment. I don't know if these were run of the mill failures or my failures in every case, but I've lost a couple of loads and a power supply in a week.
Throughout the week we work on various little things and either shoot pieces as we go along, or get them all set up to shoot quickly on Thursday and Friday. By Friday afternoon, we had NOTHING - everything we had tried to put together either had some weird failure with no explanation or we were waiting on a part, a vendor to explain why, or something similar. We went down the list Friday afternoon and all had incurable delays or halts to everything we had had a notion of doing that week.
So I went home. Had a lovely evening playing bridge and drinking wine with some friends of ours until quite late. And awoke Saturday morning with no video to edit. Nothing more complicated than that.
I must confess, that in recent weeks I've been a bit removed from our overall process and there are few cues in the shop that anyone is watching anyway. My e-mail load had dried up over the holidays as people, I guess, were enjoying the holiday. And I was feeling a little bit of end of year reflection on why we are doing this, what we are accomplishing with it, and whether it is really worth a 24x7 365 day effort. After all, I do have electric cars to drive at this point. What's the emergency, what are we REALLY accomplishing here, and why am I working this hard at age 56. Truth to tell, we're probably leading this industry by a full two years from where I had thought/hoped we were.
I know that is a bit hard to accept with daily announcements of OEM electric car offerings literally pouring from the screen. Hasn't the electric car revolution already happened and we are just mopping up the last of the late adopters and conservative majority on this one?
I fear not. More like we don't have the early tinkerers and innovators sufficiently and properly organized to sponsor an outdoor cookout even WITH the assistance of the Boy Scouts of America (BSA). I'm actually a bit discouraged that we have been unable to move that token any further than it currently lies on the ground.
In any event, it's the end of the year. I think I'm going to slow down the pace and play with what strikes me. This week it is the simple addition of an experiment with green chroma key. I was all wired up for a prolonged battle with Final Cut Pro X over green chroma key. We got a largish piece of green muslin and a frame to drape it over behind us and shot the show on faith with nothing to look at.
There were a couple of tricks but really within an hour on Saturday morning I had figured out pretty much how it worked. And lo and behold, Brain and I could be ANYWHERE in front of ANYTHING with the flick of a mouse. I know this is a very basic technique to any of you advanced video professionals. But to us country boys trying to make our way in the big city, this is astonishing. And to have a weather map that is really a schematic diagram is pretty cool for some of these discussions. Without a schematic, my talking doesn't really make any sense at all.
I have also been hard at work on TWO different A123 modules. The first, actually described to me by Kevin Wong worked quite well actually. It had a couple of minor problems but was very easy to assemble. Unfortuantely, there's no point in showing it as we've already moved on.
The second was originally described somewhat vaguely by Celso Menai of Portugal. Celso IS kind of the battery guy with a small OEM that is developing a kind of tricycle car that is really quite captivating in the video he showed us at EVCCON. This theme was expanded by Mic of Oz - an Australian who provided an animation of it on Vimeo that I rather liked.
Actually in the time I SHOULD have been making video, I've made this module THREE TIMES in prototype form. The last has some 48 cells in a 4P12S configuration for a 40 volt 75 Ah module. It is 19.75 inches long, about eight inches high and about nine inches wide and weighs about 75 lbs. It represents a 3 kWh pack.
The prototype has spaghetti wiring on it for the Cellog 8S modules to monitor individual cell voltages. We bottom balanced the entire set of cells at 2.75 volts during assembly. We'll be charging it and discharging it to see what happens to the individual cells. Under load, poor connections and so forth show up.
This is kind of a leap of faith. We used nylon threaded rod and some pvc nuts and by following Mic's instructions and including a nut with every insulated piece, we think we've managed the clamping forces as well as they can be managed. But we do not want flexing between the tabs and the spacers in the vibrating environment of a vehicle. So we've cast the ENTIRE thing in the urethane resin we've been playing with.
Actually for the prototype, we have the opaque resin in the bottom and some nearly clear resin in the top and we want to see where we are. But the thing winds up looking like a 75 lb block of ice with spaghetti wiring out the top.
A123 is of course having their own problems with their over engineered cooling system. We did something quite different. I procured some thin 0.30 aluminum sheet from our ONLINE METALS supplier done in gunmetal anodize. Anodized aluminum is kind of peculiar in that it really doesn't conduct electricity very well, but it DOES conduct heat. So we made little panels of it with a 90 degree bend at the bottom just wide enough for two cells. We slipped those between each TWO cells with the leg pointing IN toward the center.
When we put the battery in the resin form, we pulled the panels down slightly to where the feet touched the form box ends. Then we poured the resin.
We'll wire brush the resin off these thin feet, exposing the aluminum.
In this way, each cell makes contact with a full sized plate of thin aluminum. That plate extends to the END of the battery where it hooks into this 1/2 inch foot spanning the height of the assembly. I do hope this wicked any heat from any of the cells to these exposed feet. At that point, for some applications this will be adequate. But you COULD attach a chill plate, a finned heat sink, or just place the battery in an aluminum box with contact at the ends between the feet and the box.
The resin, once hardened, should effectively isolate the clamps and tabs and cells and panels from rubbing, chafing, loosening, and otherwise wearing. This is what I consider and important and unfortunate part of the design. We no longer have discrete cells to work with here and no real access to them (other than the spaghetti on the prototype).
I'm actually ok with this. We don't have access to individual foils in the CALB prismatics we use. So not having access to individual A123 cells is not so very different, except that we have some in SERIES in this battery making up a 40 volt module.
Note also the lack of BMS. I intend to use these as true batteries. If they go bad, they go away. By bottom balancing them on assembly, I'm hoping to prevent failures. : But a single bad cell in this bunch means inevitable and almost immediate failure. We should really capacity test these as well before assembly.
I've ordered a little voltmeter with programmable relay from ColdFusion. I intend to hook this up to a contactor and load situation where I can connect a cell and walk away. When it gets down to a specific voltage, ti will disconnect the cell from the load. Assuming they arrive at nearly identical state of charge, this should take them down to an identical state of low charge. I should be able to read our AH meter to detect "short" cells. And the resulting cells can be combined into an already bottom balanced assembly this way with a pretty good confidence on the capacity as well.
Three such batteries would be a 120volt 75 AH assembly and would drive one of the HPEVS systems very nicely with 9000 wH of storage in a scant 225lbs of batteries. We think this would be a 40-50 mile total range or maybe 32-35 mile range at 80% DOD. That's not far, but many people do drive less than that each day, including yours truly and frankly. The bare cell costs, delivered to us circa 1/1/12, look like about $1250 per module or $3750 for the pack. With resin, threaded rods, hardware, etc, you might be looking at a round $1500 per module or $4500.
Why is this important? Well, lead acid batteries reportedly cost $2500 and offer a 40 mile range. We happen to know that delivered to your driveway, they are more often $3000 unless you are near a battery store where you can get a deal and pick them up yourself. And the 40 mile range is almost entirely made up - wishful thinking. Lead cell cars usually get 25-30 miles in the first two months, and then it drops horrifically over the remaining two years of life. And they weigh a 1000 lbs.
Three of these modules weigh 225 lbs. They really will do 40 miles. They have the advantage of long cycle life - over 3000 cycles. And 650 amps is nothing for these cells. Our tests indicate about an 1850 ampere power output from this module.
So instead of $10,000 for batteries, you pay a 50% premium over lead, and get the same range (actually better) , MUCH lighter weight, and much longer life. If you WANTED to add more cells later in parallel to double the range, it is trivial to do so.
We did order and receive some excellent braided straps from China to replace our EVWorks source in Australia. The shipping and duties from Australia had become really quite onerous and our final cost per strap was over $5 via this avenue in all cases and in the case of the 55 mm straps considerably so.
The shipping and so forth from China is actually pretty steep as well, I think our UPS was $686 on this batch and then UPS came up with some strange $131 brokers fee on the import of these. In any event, I got 1000 of the 70 mm straps we always use on the 100 and 180Ah CALB cells. And a couple of hundred of the straps for the larger M12 bolts on the Elescalade.
We mentioned that it looked like that put us in the strap business whether on purpose or by accident. THree of our viewers have ordered in the first twelve hours so I guess this will be worthwhile. We're going to put together a set of one 70mm strap, two 18-8 stainless 16 mm M8 bolts, and two zinc coated M8 Nordlock washers for $7 plus shipping. We'll work on getting some sort of page up that calculates shipping and totals and so forth to make it easy. The larger set for the 400 Ah cells would be $10 per set, but I would be astonished if anyone but us needs those at all.
What I call 70mm straps have 8x13mm holes on 70mm centers. The strap is actually 98 mm long and 24 mm wide of tinned copper braided wire with tinned copper on the ends. We'll put some photos on the web page when we get it up.
In the meantime, all of you that did send e-mail and Paypal donations this past week, fearing our demise, we deeply appreciate them. It IS true enough that if we don't find some economic basis for doing this, it cannot continue forever. But that's not precisely why we missed a week now. But operating with Brian and I and Rod in a dark shop in the cold of winter, we kind of lose sight that anyone is watching or that anyone cares. There's no shortage of video on YouTube we are well aware. And so our confidence in our mission naturally wanes. The encouragement is actually as important or more important than the donations, but encouragement in DECIMAL is of course the most sincere. I only contribute actual ducats when I actually want to support something. It's not just happy talk. And we assume you all do the same. So I was encouraged this week. Our viewership appears to be growing and we appear to have the requisite "stickiness" among a set of viewers that keep coming back. That means eventual success if we simply persevere.
We're hardly alone in our struggles. George Hamstra has 100 motors with no aux shaft as the result of an OEM failure (I'm telling you selling to OEMs is not all as great as you think guys) and Sebastien Bourgoius reports costs on the Shiva have driven them to an atmospheric $9500 for their megawatt controller. So everyone is having their version of a bad hair day at the moment.
But stay with us. If this thing with Iran doesn't get resolved here pretty soon, we could ALL be heading for a bad hair day at the pump. And we're just not sufficiently far enough along with all this to deal with it.
Jack Rickard
Monday, January 2, 2012
And a Happy New Year.
We conclude 2011 with one of the most gruesome video edits we've ever done and a show that is two hours and 45 minutes in length. I suppose the question must come up, WHY.
Some of our viewers want more detail. And the A123 cell thing turns out to be a pretty big deal.
I should hate these cells and I very much want to detest them quite thoroughly. The company they come from, their actions, their attitude, their web site, their history, their dependence on gubbmint munny, almost everything about these people is anathema to me. That they are currently failing actually DOES give me satisfaction if not a bit of New Year's joy.
And so there is nothing I would like better than to finally receive some of their cells and slaughter them publicly for your entertainment and my personal satisfaction.
And truly it does puzzle me why they would make a 19 Ah cell and title it a 21 Ah cell. What would be DIFFERENT in putting a few more foils in it and making it a 21 Ah cells and calling it a 20 Ah cell????
In truth you cannot purchase these cells form the company anyway, and by the time they wake up to what's happening and sell them to you directly, they will of course then ask something stupid like $50 per cell for cells you can get from China for $20.
Ultimately, I don't know of course what the price of these cells is. They are made in an Asian factory. A123 doesn't need as many as they thought they did. And they are available. How much do they cost the factory to produce? Probably 60 cents per AH. For everyone to get their little piece, we are probably there at $1 or $0.90, But the factory is not going to just shut down as long as sales can be made.
And indeed A123 has actually licensed OTHER Asian companies to use the cells out of the same factories or to produce their own - mostly Japanese.
So my best guess is they ARE going to be available, and the price will slowly fall.
We have been doing some testing. This week we formalized that a bit. How much power WILL these cells put out and how much CAPACITY do they actually have.
It appears that most DO have a capacity somewhere between 18.5 and 19 Ah. And we actually have CONFIRMED output at 23C. That is, I have watched two separate and independent meters indicate currents of 475 amps twice from a single series of 3 cells starting at 10.00v. Their claim of 360 Amps or 18C is a LOCK.
And so a block of six cells, analogous to a 100Ah prismatic, can really do 1800 amps no sweat and we have actually seen a 2300 amp level with two meters twice.
What THAT means is I could actually drive the EleScalade with TWO 1000 Amp EVnetics Soliton controllers and two 11 inch Netgain motors at 2000 amps with a single string of 100Ah modules of these cells. That would be 57 x 6 or 342 cells. It would cost $9576 delivered. And it would be 19200 wH in size.
Compare this to our current 76kWh pack at about $25,000.
Now we would probably have a range of about 20 to 25 miles with the A123 pack and I think we'll be close to 100 miles with the pack we have. But we're over 1700 lbs in battery and box at the moment. The A123 pack would weigh more like 450 lbs all assembled in a box.
I have to admit that life won't' change much for us. Other than some demonstration projects, we would almost always go for the larger prismatic cells. That tough plastic case is just bullet proof. And I like my cars to go 100 miles. I see no sense in all the OTHER expenditures it makes to have a Cadillac Elescalade and then scrimp on battery costs - cropping the range.
But I think a lot of people noodling an EV, will find this attractive. Here's why.
Let's say it takes $17,000 to do the average conversion including batteries at $8500. If I can cut that to $4500 in batteries, that gets me down to $13,500. The car works. It runs. And I can always add ANOTHER $4500 in these cells later for more range.
I think they will get people into the game that just were not going to go there at the higher price.
I could pick up a Speedster for $20K on eBay, sell the engine for $2500, do the conversion for $13,500 and have a nice little sports car with 40 mile range for $30.5K smooth. That works for most people.
The other obvious application is racing. Low weight, high power, and don't worry about the range we're only going 1/4 mile. No brainer.
We did somethings with multiple cameras and closeup cameras that Final Cut X really doesn't want to do. So I wound up in editing hell. But in this episode, we actually show detailed step by step on how to build a little clamp terminal for these push cells, and then tested the cells.
See what you think.
We're hoping to find SOME economic reason to HAVE EVTV in 2012. Waiting eternally for the EV industry to grow up sufficiently to need an advertising medium insn't in my playbook at age 56. But I'm hopeful it will all come together this year.
Jack Rickard
Some of our viewers want more detail. And the A123 cell thing turns out to be a pretty big deal.
I should hate these cells and I very much want to detest them quite thoroughly. The company they come from, their actions, their attitude, their web site, their history, their dependence on gubbmint munny, almost everything about these people is anathema to me. That they are currently failing actually DOES give me satisfaction if not a bit of New Year's joy.
And so there is nothing I would like better than to finally receive some of their cells and slaughter them publicly for your entertainment and my personal satisfaction.
And truly it does puzzle me why they would make a 19 Ah cell and title it a 21 Ah cell. What would be DIFFERENT in putting a few more foils in it and making it a 21 Ah cells and calling it a 20 Ah cell????
In truth you cannot purchase these cells form the company anyway, and by the time they wake up to what's happening and sell them to you directly, they will of course then ask something stupid like $50 per cell for cells you can get from China for $20.
Ultimately, I don't know of course what the price of these cells is. They are made in an Asian factory. A123 doesn't need as many as they thought they did. And they are available. How much do they cost the factory to produce? Probably 60 cents per AH. For everyone to get their little piece, we are probably there at $1 or $0.90, But the factory is not going to just shut down as long as sales can be made.
And indeed A123 has actually licensed OTHER Asian companies to use the cells out of the same factories or to produce their own - mostly Japanese.
So my best guess is they ARE going to be available, and the price will slowly fall.
We have been doing some testing. This week we formalized that a bit. How much power WILL these cells put out and how much CAPACITY do they actually have.
It appears that most DO have a capacity somewhere between 18.5 and 19 Ah. And we actually have CONFIRMED output at 23C. That is, I have watched two separate and independent meters indicate currents of 475 amps twice from a single series of 3 cells starting at 10.00v. Their claim of 360 Amps or 18C is a LOCK.
And so a block of six cells, analogous to a 100Ah prismatic, can really do 1800 amps no sweat and we have actually seen a 2300 amp level with two meters twice.
What THAT means is I could actually drive the EleScalade with TWO 1000 Amp EVnetics Soliton controllers and two 11 inch Netgain motors at 2000 amps with a single string of 100Ah modules of these cells. That would be 57 x 6 or 342 cells. It would cost $9576 delivered. And it would be 19200 wH in size.
Compare this to our current 76kWh pack at about $25,000.
Now we would probably have a range of about 20 to 25 miles with the A123 pack and I think we'll be close to 100 miles with the pack we have. But we're over 1700 lbs in battery and box at the moment. The A123 pack would weigh more like 450 lbs all assembled in a box.
I have to admit that life won't' change much for us. Other than some demonstration projects, we would almost always go for the larger prismatic cells. That tough plastic case is just bullet proof. And I like my cars to go 100 miles. I see no sense in all the OTHER expenditures it makes to have a Cadillac Elescalade and then scrimp on battery costs - cropping the range.
But I think a lot of people noodling an EV, will find this attractive. Here's why.
Let's say it takes $17,000 to do the average conversion including batteries at $8500. If I can cut that to $4500 in batteries, that gets me down to $13,500. The car works. It runs. And I can always add ANOTHER $4500 in these cells later for more range.
I think they will get people into the game that just were not going to go there at the higher price.
I could pick up a Speedster for $20K on eBay, sell the engine for $2500, do the conversion for $13,500 and have a nice little sports car with 40 mile range for $30.5K smooth. That works for most people.
The other obvious application is racing. Low weight, high power, and don't worry about the range we're only going 1/4 mile. No brainer.
We did somethings with multiple cameras and closeup cameras that Final Cut X really doesn't want to do. So I wound up in editing hell. But in this episode, we actually show detailed step by step on how to build a little clamp terminal for these push cells, and then tested the cells.
See what you think.
We're hoping to find SOME economic reason to HAVE EVTV in 2012. Waiting eternally for the EV industry to grow up sufficiently to need an advertising medium insn't in my playbook at age 56. But I'm hopeful it will all come together this year.
Jack Rickard
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