Wednesday, August 24, 2011
How Far Does Your Electric Car Go?
How far do you want it to go?
Almost every discussion of electric vehicles STARTS with the concept of range. This is because it has always been the defining limitation of electric cars. In the early days of the Internet, electronic bulletin boards, and online communications, it was always "how fast is your modem connection."
Fast is relative. Incremental advances are NOT all created equal. The jump from 300 baud to 1200 baud was an ENORMOUS improvement. The jump from 1200 to 2400 was great. The jump from 2400 to 9600 was a good improvement. To 28.8 kbps was good too. And to 56.7k was a bit of a yawner.
Range similarly. The difference between 25 mile range (and falling) provided by Pb chemistry cells and the 80-100 mile range offered by LiFePo4 cells is ENORMOUS. From 80 to 200 would of course be very good. After that, I doubt that it matters to most.
Indeed, the average daily use of automobiles in the United States is 39.4 miles for about 14,500 miles per year. And over half the driving population averages under 26 miles per day. People just don't drive as much as they think they drive. But of course, owning a car means being ABLE to go as far as you like, not so much that you DO.
The internal combustion engine driven vehicles of course vary in range depending on how you drive the car. And they are about 12% efficient at translating some 33kWh of energy in each gallon of gasoline into forward motion. By far the majority of it is converted to HEAT and blown out through the radiator in the front of the car - each vehicle contributing to our warmth and comfort during the winter.
Electric vehicles are more like 85% efficient. But that efficiency is precisely what makes them MORE sensitive to just how they are driven.
In this weeks show, we begin a series of tests to demonstrate the factors in the vehicle design that affect this range for a given driving scenario. And we compare two cars that SHOULD have the same range, and somewhat mysteriously do not.
In my own opinion, we need to strongly alter our relationship to our vehicles and how we view them and relate to them. I do NOT actually fall into the camp where we should "suffer" for the sake of the planet. Technical problems usually can be attacked with technical solutions and this one is no different. Keep your Yukon or Denali for towing the boat to the lake or the trip to the nearby city to pickup someone at the airport. Take your long distance trips across the country as much as you like in your Escalade or Suburban. You aren't hurting ANYTHING because you are not doing enough of all that to move the decimal place. If typical, 95% of your driving is to the hardware store, the lawn center, the grocery store, the soccer field, and to school and work. And the mileage you are ACTUALLY driving in any one gulp is trivial - in some cases within Pb chemistry range.
But cars have become more expensive. In the 1960's, $4000 was a LOT for a car - picture a new Vette or a Cadillac. Today, $50-$80K is NOT stratospheric. That's the cost of a house in years past.
Now you wouldn't send a house to the junkyard after 9.6 years and build a new one. You might remodel the kitchen. You might do a little paint and carpet. But the very deliberately planned obsolescence from our friends at the automobile factory has led us to some ridiculous concepts. Today, you can TOTALLY REPLACE the drive train in any automobile - engine, transmission, and all belts and hoses, for LESS money than the SALES TAX is typically on a new vehicle. You COULD put an entirely new interior in a car for about $3000 - done by professionals. A paint job? if you want to be the rage at the next car show- $6000-$7000. But Earl Scheib DID make a fortune with his "ANY CAR - $49.95" paint job.
And so my intent is to pick cars I really like, and then just renovate them as needed. That pretty much precludes the use of steel bodies. I like aluminum and fiberglass because they don't try to become biodegradable and return to the earth as rust while I drive them.
With the advent of these LiFePo4 cells and electric drive trains, I can see simply continually upgrading a car forever. We'll not build it. We'll build it for life and we'll keep building it. As batteries become available, or controllers, or chargers, we will upgrade. If the paint fades and accumulates some scratches, we'll have it painted.
Back to the main topic of this week's show. Range. It does require the application of power to move a car at all. How far it moves is a function of how much power. There are several factors that determine just how MUCH power is required. Since your battery pack offers a FIXED amount of power, your range is the result of your relationship to those factors.
INERTIA. The tendency of a body at rest is to remain at rest and for a body in motion to remain in motion. Without other factors, if you had a car going 25 miles per hour, it would go 25 miles per hour forever with NO additional power. Friction, and other factors cause it to decelerate - eventually to a stop.
You have to apply power to accelerate to any speed, and other resistances will cause you to DECLERATE from that speed to zero. The amount of power required is a function of MASS. The greater the mass the more power to accelerate.
This is entirely separate from gravity. But when we combine gravity and mass, we can derive a very measurable quantity - WEIGHT. And so the amount of power required to accelerate to a given speed can be though of primarily as a function of weight.
GRAVITY is indeed one of the factors in electric car design. All roads have some incline. To climb a hill, you must move the mass in elevation against the force of gravity. In a downhill run, gravity can actually decrease the amount of power required to a negative number, and indeed you can recover energy through regenerative braking - converting both inertia and gravity into electrical power to recharge your cells.
AERODYNAMIC DRAG is actually one the most significant forces involved in range. As anyone who has put their hand out the window at 60 mph knows, the force of the relative wind can be felt as quite a strong force. That is aerodynamic drag experienced across probably 20 square inches of hand. In the case of the Spyder or the Speedster, that same force is multiplied by the 1.76 square meters of frontal area if you can imagine it. It is an enormous force.
The aerodynamic drag force can actually be given by the formula Fd=1/2 pv2CdA.
Fd is the resulting drag force.
p is the density of the fluid - in this case air and is slightly variable by temperature.
Cd is a "drag coefficient" typically derived from wind tunnel testing to account for the fact that for a given frontal area the drag will vary according to the shape of the vehicle and the resulting laminar flow of air across the body.
A is the total "frontal" area of the car. How big is the hand.
v is the culprit - velocity. It is squared. In this equation, whatever v is is multiplied by itself. If it is 10 mph, it equals 100. And if it is 100, it equals 10,000. This cruel fact is what caused such an enormous difference in power at 70 mph than at 40. Recall Jimmy Carter's 55 mph speed limit. It was not invoked to save lives - but rather to save gasoline. And as I mentioned, electric cars are MORE sensitive to such things than the gasoline cars because they are MORE efficient in the first place.
After inertia, gravity, and aerodynamic drag, we have rolling resistance. If you put your car in neutral, and push it out of the garage by hand, you are experiencing it's rolling resistance first hand.
The biggest component of rolling resistance is probably the tires. Large fat squishy tires give us a very comfortable ride. But the flexing of the sidewalls to accomplish this generates heat loss and makes the car difficult to roll. The larger the contact area of the tires with the pavement, the larger the rolling resistance. If you don't have pavement, and are driving on sand for example, it gets worse.
But there are drive train resistances as well. The friction of the gears in the transmission and differential add a bit of drag to the system. The bearings in the car support the entire weight of the car on the wheels while allowing wheel rotation. Whatever your car weighs, each wheel has to carry part of that and it does so primarily through the wheel bearings. They have friction, and give off heat. If you have one that goes "dry" and is not lubricated, it will generate enough heat to melt steel.
This week, we did some testing of the 1957 Porsche Speedster Electric we call DUH, because it was our second speedster build - part deux. And we also tested a 1955 Porsche 550 Spyder electric replica that we consulted on when it was originally built by Duane Ball and Scott Smith, and subsequently we bought the car.
We tried to eliminate INERTIA and GRAVITY from the test. We did this by driving a substantial distance of about 20 miles at a steady speed. Not accelerating and not decelerating pretty much eliminated the application of power for the purposes of inertia - just what we needed to get up to speed in a few hundred yards out of the 20 miles. And even that was largely cancelled by the recovered energy or lack of force required for the distance we decelerated.
All roads have slope. We divided the 20 miles into two halves and did them in opposite directions on the same road. This should pretty much cancel the effects of gravity.
Leaving aerodynamic drag and rolling resistance. We tested both cars on the same route and nominally at the same steady speeds of 40 mph, 50 mph, 60 mph and 70 mph. Let's look at the results.
If we look at these results, a couple of things jump out at you. At 40 mph, the Speedster gets 19.69% greater range at 158 miles than the Spyder at 132 miles. Also curious is that this advantage decreases to 9.3% at 70mph with the Speedster coming out to 94 miles and the Spyder at 86.
That brings up two questions: Why does the Speedster have greater range? And why does this disparity vary with speed?
And these questions jump from curious to bizarre when we look at the two cars.
Weight:
Speedster: 2035
Spyder: 1903
Coefficient of drag:
Speedster: 0.40
Spyder : 0.20
The Speedster should be LESS efficient than the Spyder by quite a bit. I confess the references to Cd on the Spyder are slim. There were only 90 of these vehicles built originally and wind tunnel testing wasn't a big deal in those days. But just looking at the two shapes, you would expect the Spyder to be dramatically more slippery through the air. Both vehicles have a frontal area of 1.76 square meters.
As we took the weight largely out of the picture by eliminating Inertia and Gravity, that's not a big mystery.
The cars are similar in other ways as well. They both have 36 China Aviation Lithium Battery Company cells of 180Ah per cell. They operate at the same voltage. They have the same High Performance Electric Vehicle Systems AC-50 motor. They both used the Curtis 1238 three-phase controller. In this, the Spyder features the 650 amp -7601 controller variant while the Speedster has the 550 ampere -7501 controller. But we never went over 200 amps in any event. Both controllers were set for 5% neutral braking and 500 rpm taper. These are controller configuration items controlling the amount of regenerative braking.
They both now use the same hall effect accelerator.
They DO have different transmissions with the Spyder having a 3.88:1 ring and pinion and the Speedster featuring a 3.44:1 ring and pinion. But the other gears result in almost identical final ratios between the two cars. Alll the testing was done in fourth gear. There was a 100 rpm difference at 60 and 70 mph but almost identical rpm at 40 and 50 mph.
The Spyder features a GPS speedometer and the Speedster features a cable driven speedometer calibrated in MPH. Or should I say miscalibrated. There is a 2.3 % difference from the GPS which we assume to be true distance and speed. This is undoubtedly part of the mystery, but doesn't quite cover the question in degree I'm afraid. It is less than 2 mph and that kind of gets down into the noise level of what I can maintain as far as a steady speed on an Interstate highway with traffic. We used the distance measured by the Spyder for all calculations.
The clue is in the disparity between the 40 mph results and the 70 mph results. If aerodynamics accounts for 1/2 the difference between the two, and rolling resistance the other half, as we increase in speed the aerodynamics should increase as a percentage of the total as aerodynamic drag increases. Rolling resistance may increase, but not as a square function and really not by much.
In this case, the difference between the two vehicles decreases from 19% at 40 mph to 9% at 70 mph. What this tells me is that as aerodynamic forces become a LARGER percentage of the total problem, the difference between the two vehicles DIMINISHES. And so the difference is NOT attributable to aerodynamic difference at all. It must therefore be attributable to rolling resistance.
The Spyder has a set of 165/65 R15 Khumo tires on it. The Speedster features a new set of Michelin Energy Saver All Season 185/60 R15s. It also has some Moon Eye wheel covers which might lend a bit of aerodynamic assistance.
The Spyder started life as a WIDE FIVE option from Beck Speedsters. This is historically accurate but problematical. There aren't many wheels drilled to FIT the Porsche wide five pattern. So Duane had put a set of 911 aluminum wheels on the car with an adapter that moved the wheels out about an inch. This caused the wheels to rub on the body fender in front when steering. So they jacked up the front of the car - probably hosing up the aerodynamics in the process.
In any event, I never liked the setup in the first place. And there were "noises" from the rear of the car. I kept telling Brian I had a brake dragging but he never could really find any evidence of that.
In any event, we contacted AIRKEWELD. They make a very interesting aluminum brake rotor that has a billet aluminum hat that bolts on - allowing them to do any wheel pattern and offset desired with a very lightweight rotor. They couple that with a Wildewood aluminum caliper. This little puppy would reduce our unsprung weight by about 18 lbs. Aluminum rotors and calipers are not nearly as durable as steel and we would not normally recommend their use on a car. But this car features regenerative braking anyway. We don't really use the disk brakes much at all. So we think it would be a good upgrade for this particular electric car.
We add a lightweight Weld aluminum wheel in a Ford 5 by 4.5 pattern. And on this, we'll mount a low rolling resistance tire. The Michelin Energy Saver A/S curiously is SOLD OUT NATIONALLY. You can't get em - anywhere. Brian has confirmed with Michelin directly that they do not exist at the moment. They are a little mysterious as to why this might be. We suspect they are redesigning for even lower resistance.
Tirerack.com tested low rolling resistance tires on a Prius and Michelins got the highest mileage at 53.8 mpg, compared to the Goodyear Insight that comes standard on the Prius at about 51.5 mpg. But the Bridgestone Ecopia rated just a little behind the Michelin and is $25 per tire less AND they are not unobtanium.
The Bridgestone and Weld combination is about 2 lbs lighter than the earlier Porsche style aluminum wheel and Khumo. The Bridgestone Tire weighs 17 lbs and the wheel a little over 12 lbs.
Unfortunately, AIRKEWELD is an American Company. ANd like all non-Chinese American companies, they cannot manage to get an order in a box and shipped from Arizona to Missouri without at least three tries. We got the long axle version on the rear hubs when we had specified the short axle. We got the wrong brackets for the front. And we go the wrong brake lines for the rear. ANd we got the wrong brake pads for the Wildewood calipers in the front. It has been a total comedy and we have now received our THIRD shipment from these guys. The parts were ordered in June and received in late August (on three different dates of course). And they were $1800, which approaches 10% of the cost of the original vehicle roller.
But they were very nice and the units are just gorgeous. We should have them on this week, and be ready for retesting. It will be very interesting to see the results.
We are also installing some Silicon Nitride ceramic bearings on the rear axles of the Spyder. This is a standard 6306 bearing which normally costs $12.95. The ceramic version is $325 each. But they are good up to 2550F and have significantly lower friction. I guess I think we are stringing the bounds of reality here at a $650 upgrade to avoid bearing friction. But the Illuminati team claim it is their secret sauce on their vehicle which gets very good efficiency on the highway and is nearly 3000 lbs to boot.
We don't do very well with secrets at EVTV. If you have any, tell them to someone else if you want them to remain a secret.
Jack Rickard
Sunday, August 14, 2011
Shorter and LIghter - Should Jenny Craig be Part of EVTV?
Somebody called to see if I would be around this week. My response, unfortunately so. You see, I always wanted to be a tall. But it was the whim of genetics and my own proclivity for good food that decreed I should be a ROUND forever.
A short show this week. And I like that. Somehow, we've crept up to two and a half hours. This is longer than a feature length film by nearly an hour. We're going to try to shorten things up. We've reached the limit and I'm spending most of the weekend editing video.
This week, we do a little bit of news, and show a test of our Netgain Warp11HV motor prior to installation. We also mount our Tremec TKO600 transmission.
The transmission mount is a little more free form than I like. The Cobra came a bit blank. There was a cross bar under the car, which turns out to be in the wrong place, and a hole cut for the shifter - almost in the wrong place. The rest of the transmission mounting is just sort of left up to us.
We bought a low profile mount for the rear - just a block of polyurethane to shock mount it really. We had a local race car guy build us a little brace for it. We'll have to cutout the existing brace and lower it so the drive shaft can clear.
Danny, the race car builder, suggested we could save 100 lbs by replacing the third member on the differential with an aluminum one. But when we checked with his supplier, he said he didn't have one for THAT Ford 9 inch. Apparently a Ford 9 inch differential covers a multitude of sins.
For the front of the transmission, we fashioned two small brackets that bolt to the bell housing and a pair of Mazda RX7 polyurethane shock mounts we found on eBay for $77.
We'll install the motor to the bell housing and fashion a similar plate/mount for the front of the motor with another pair of these shock mounts.
Hopefully, the drive train will then be pretty securely mounted aft, middle, and foreword. We'll need to have a drive shaft made specifically for the vehicle of course.
The convention draws closer. Brain has devised a 20 booth vendor floor and I understand they've signed four at this point. We're quite pleased that Special Editions Inc. will be bringing a Beck roller to show. We've used several of these in the past and they just make a great platform for a simple electric vehicle conversion. Best of all, they are truly head turners.
I came out of the local Schnucks grocery store with some cheap Champagne and cheese and crackers headed in a hurry to a hastily thrown together bridge game, since I managed to get the video up by Saturday afternoon this week. There were eight people gathered round the Beck Speedster we call Part Duh in the parking lot. They were marveling over the car and had twenty questions about it. Understand they did not even know it was electric. Just the iconic shape of the car still works 54 years after it was introduced. We have no Porsche badging on it. We have the moon eye hub caps. It isn't a Porsche. It says Porsche nowhere on it. They truly had NO idea what it was. But they were instantly drawn to the car.
I did note that it was electric drive and pointed to the very subtle ELECTRIC emblem we had made to match the small SPEEDSTER gold emblem on the front fender. And they more or less went berserk.
Brain had a similar adventure last week when he took the Spyder 550 to a car show in Sikeston. He came back with a SECOND place trophy. I don't know what THAT was about. But he returned with a sunburn as the attendees wouldn't let him step away from the car for about four hours. They Spyder is particularly good at these events as you can open it up like a clam and display all the componentry almost like it was layed out on a workbench.
It goes slowly, but we are working with Special Editions on a special frame for a Beck Speedster. This will be quite a departure in a number of ways. I like rack and pinion steering for example. And independent rear suspension. But there is talk of turning the axle around for a mid-engine version, which would free us for more room in the rear for batteries. Best of all, we are going to have it done of aluminum, which should shave a couple of hundred pounds off the weight. I've always liked the Beck Speedsters because they have a frame under them sufficient to mount a Ford F150 instead of the usual VW pan. But in truth, it IS overbuilt and overweight for our needs.
And this next week we should receive a set of running gear for the Spyder we are trying out that will eventually be part of the next Speedster build. Airkeweld makes an aluminum cross drilled rotor and they can put any hat on it we want - I think we got 5 x 4.5. We already have a set of Weld lightweight aluminum wheels for it. For the front we can use the Wildewood aluminum calipers as well but for the rear they do not make such with a parking brake on it. We have to have a parking brake. They are much more important on an electric car.
On the Spyder this will be a particular advantage. Duane had some 911 wheels on the car he liked but this required an adapter that sets out the wheels an inch or so. As a result, the front end has to be jacked up so the wheels clear the body. All in all not to my taste. So the new running gear and wheels will let us get the wheels back inside and the front end down - while saving about 150 pounds on an already light car. As this is almost entirely unsprung weight that goes away, I'm looking for GREAT things by way of improved handling with the front end down where we want it and this weight savings.
If any of it works, that system will be migrated to the new Beck aluminum frame and we should save somewhere between 300-400 lbs overall. This is actually an incredible amount. Speedster Part Duh weighs 2035 lbs now and could be down to 1650 or so eventually. All of this BEFORE we take on the body at some time in the future.
It also has passed little notice but the DOT has now approved polycarbonate windshields. I like glass. But the weight savings here too are substantial. And I already did have to replace the windshield on Duh because of a flying rock. None of that with polycarbonate. Yes, they haze. But there are now very effective polishes you can use to clarify polycarbonate more or less endlessly. We've used them on the Lear 24D for years. If they are good enough for a Mach 0.78 jet, they should be sufficient for a Speedster.
And it really is about weight. I was enormously validated when Brian ran both the Spyder and the Redux in the autocross at Carlisle. It was NOT close and it was repeated several times. The lap is about 30 seconds and the Spyder, with much lower power and acceleration, just killed Redux by 3 seconds every time - 10% of the course.
This of course was PRECISELY the lesson learned in 1955 with the introduction of the Spyder on the racing scene of the day. It was much less powerful than any of its competitors, yet it won every race it finished that year.
With an internal combustion engine, the cost of these weight savings simply don't make much economic sense. For an electric car, they quite do. And as a result, we're finding common ground with the race car guys.
We have developed a fondness for the Michelin Energy Saver All Season tire. This tire has the lowest rolling resistance of any tire on the market. Unfortunately, it appears it is not ON the market. They are sold out NATIONALLY on this tire. No estimate on restock dates. You cannot get them. That's going to slow our thunder on the Spyder.
Fortunately, we already HAVE a set of them on some lightweight Weld wheels for the Cobra. And we're going to do an interesting experiment there. Not only do the Michelin's feature a lower rolling resistance, but our total weight on the Weld wheels/tires is 31 lbs each. The existing wheels and tires that came on the car were 42 lbs on the front and 48 lbs on the rear. We save 22 lbs on the front and 34 lbs on the rear for 56 lbs total going to these lighter tires/wheels. So we are going to do a range comparison on the car by running say 100Ah exactly on each set and noting the mileage covered in those 100Ah. I think it will be significant - more than you think. Maybe 5 or 6%.
All these sorts of things are quite cumulative. An LED tail light bulb here and a tire there, it all adds up. And it all counts in the end car.
Not to mention the weight of the driver.... there was a solid reason that Brain drove both cars at Carlisle.
Jack Rickard
A short show this week. And I like that. Somehow, we've crept up to two and a half hours. This is longer than a feature length film by nearly an hour. We're going to try to shorten things up. We've reached the limit and I'm spending most of the weekend editing video.
This week, we do a little bit of news, and show a test of our Netgain Warp11HV motor prior to installation. We also mount our Tremec TKO600 transmission.
The transmission mount is a little more free form than I like. The Cobra came a bit blank. There was a cross bar under the car, which turns out to be in the wrong place, and a hole cut for the shifter - almost in the wrong place. The rest of the transmission mounting is just sort of left up to us.
We bought a low profile mount for the rear - just a block of polyurethane to shock mount it really. We had a local race car guy build us a little brace for it. We'll have to cutout the existing brace and lower it so the drive shaft can clear.
Danny, the race car builder, suggested we could save 100 lbs by replacing the third member on the differential with an aluminum one. But when we checked with his supplier, he said he didn't have one for THAT Ford 9 inch. Apparently a Ford 9 inch differential covers a multitude of sins.
For the front of the transmission, we fashioned two small brackets that bolt to the bell housing and a pair of Mazda RX7 polyurethane shock mounts we found on eBay for $77.
We'll install the motor to the bell housing and fashion a similar plate/mount for the front of the motor with another pair of these shock mounts.
Hopefully, the drive train will then be pretty securely mounted aft, middle, and foreword. We'll need to have a drive shaft made specifically for the vehicle of course.
The convention draws closer. Brain has devised a 20 booth vendor floor and I understand they've signed four at this point. We're quite pleased that Special Editions Inc. will be bringing a Beck roller to show. We've used several of these in the past and they just make a great platform for a simple electric vehicle conversion. Best of all, they are truly head turners.
I came out of the local Schnucks grocery store with some cheap Champagne and cheese and crackers headed in a hurry to a hastily thrown together bridge game, since I managed to get the video up by Saturday afternoon this week. There were eight people gathered round the Beck Speedster we call Part Duh in the parking lot. They were marveling over the car and had twenty questions about it. Understand they did not even know it was electric. Just the iconic shape of the car still works 54 years after it was introduced. We have no Porsche badging on it. We have the moon eye hub caps. It isn't a Porsche. It says Porsche nowhere on it. They truly had NO idea what it was. But they were instantly drawn to the car.
I did note that it was electric drive and pointed to the very subtle ELECTRIC emblem we had made to match the small SPEEDSTER gold emblem on the front fender. And they more or less went berserk.
Brain had a similar adventure last week when he took the Spyder 550 to a car show in Sikeston. He came back with a SECOND place trophy. I don't know what THAT was about. But he returned with a sunburn as the attendees wouldn't let him step away from the car for about four hours. They Spyder is particularly good at these events as you can open it up like a clam and display all the componentry almost like it was layed out on a workbench.
It goes slowly, but we are working with Special Editions on a special frame for a Beck Speedster. This will be quite a departure in a number of ways. I like rack and pinion steering for example. And independent rear suspension. But there is talk of turning the axle around for a mid-engine version, which would free us for more room in the rear for batteries. Best of all, we are going to have it done of aluminum, which should shave a couple of hundred pounds off the weight. I've always liked the Beck Speedsters because they have a frame under them sufficient to mount a Ford F150 instead of the usual VW pan. But in truth, it IS overbuilt and overweight for our needs.
And this next week we should receive a set of running gear for the Spyder we are trying out that will eventually be part of the next Speedster build. Airkeweld makes an aluminum cross drilled rotor and they can put any hat on it we want - I think we got 5 x 4.5. We already have a set of Weld lightweight aluminum wheels for it. For the front we can use the Wildewood aluminum calipers as well but for the rear they do not make such with a parking brake on it. We have to have a parking brake. They are much more important on an electric car.
On the Spyder this will be a particular advantage. Duane had some 911 wheels on the car he liked but this required an adapter that sets out the wheels an inch or so. As a result, the front end has to be jacked up so the wheels clear the body. All in all not to my taste. So the new running gear and wheels will let us get the wheels back inside and the front end down - while saving about 150 pounds on an already light car. As this is almost entirely unsprung weight that goes away, I'm looking for GREAT things by way of improved handling with the front end down where we want it and this weight savings.
If any of it works, that system will be migrated to the new Beck aluminum frame and we should save somewhere between 300-400 lbs overall. This is actually an incredible amount. Speedster Part Duh weighs 2035 lbs now and could be down to 1650 or so eventually. All of this BEFORE we take on the body at some time in the future.
It also has passed little notice but the DOT has now approved polycarbonate windshields. I like glass. But the weight savings here too are substantial. And I already did have to replace the windshield on Duh because of a flying rock. None of that with polycarbonate. Yes, they haze. But there are now very effective polishes you can use to clarify polycarbonate more or less endlessly. We've used them on the Lear 24D for years. If they are good enough for a Mach 0.78 jet, they should be sufficient for a Speedster.
And it really is about weight. I was enormously validated when Brian ran both the Spyder and the Redux in the autocross at Carlisle. It was NOT close and it was repeated several times. The lap is about 30 seconds and the Spyder, with much lower power and acceleration, just killed Redux by 3 seconds every time - 10% of the course.
This of course was PRECISELY the lesson learned in 1955 with the introduction of the Spyder on the racing scene of the day. It was much less powerful than any of its competitors, yet it won every race it finished that year.
With an internal combustion engine, the cost of these weight savings simply don't make much economic sense. For an electric car, they quite do. And as a result, we're finding common ground with the race car guys.
We have developed a fondness for the Michelin Energy Saver All Season tire. This tire has the lowest rolling resistance of any tire on the market. Unfortunately, it appears it is not ON the market. They are sold out NATIONALLY on this tire. No estimate on restock dates. You cannot get them. That's going to slow our thunder on the Spyder.
Fortunately, we already HAVE a set of them on some lightweight Weld wheels for the Cobra. And we're going to do an interesting experiment there. Not only do the Michelin's feature a lower rolling resistance, but our total weight on the Weld wheels/tires is 31 lbs each. The existing wheels and tires that came on the car were 42 lbs on the front and 48 lbs on the rear. We save 22 lbs on the front and 34 lbs on the rear for 56 lbs total going to these lighter tires/wheels. So we are going to do a range comparison on the car by running say 100Ah exactly on each set and noting the mileage covered in those 100Ah. I think it will be significant - more than you think. Maybe 5 or 6%.
All these sorts of things are quite cumulative. An LED tail light bulb here and a tire there, it all adds up. And it all counts in the end car.
Not to mention the weight of the driver.... there was a solid reason that Brain drove both cars at Carlisle.
Jack Rickard
Monday, August 8, 2011
The Joys of Fantasy and the Sharp Edge of Truth
This week's show is kind of a hodge podge. Again we are heat limited in Missouri as to actually doing very much.
We completed the rear battery boxes on the eCobra and moved to the belly boxes on each side of the vehicle behind the exhaust pipes. We did do a bit of cable work with the 2/0 shielded cable we've adopted to limit noise. I repeatedly call this TWO AWG in the video. Not sure why. It was always 2/0 and in fact that's mostly what we've used for electric cars over the past years.
The underside of a car is a handy place to put cells out of the way and has been a tradition for many years. We have a 1994 van with all cells mounted underneath in a rack that hangs so low as to make the vehicle look impractical, which it probably is. Even the Tesla Model S has all batteries slung underneath.
The question of course comes up - what happens when it rains? I don't have an answer actually. It's kind of a moot point in an open cockpit roadster methinks. But a curious question nonetheless.
We actually did inherit a Ford Edge that was such a mess I have not mentioned it. We've fixed a few things, but are a long way from having much. The automatic transmission lurches alarmingly at all speeds. It needs 600-700 watt-hours to careen a mile down the road. Weighs 5000 lbs. One of the things we found was a truly curious propensity to build battery racks out of angle iron that lips over the top edge of the cells. This is quite heavy, quite strong, and secures the batteries quite famously. Unfortunately, it brings the frame iron within a tiny fraction of an inch of the terminals and I view all this with abject horror. Please don't do this. It is a very effective technique for lead acid or AGM 6 or 12v cells, and it is probably suicidal with LiFePo4 cells. In this case, one rack underneath had the cells laying on edge facing forward with the terminals toward the front of the car and entirely open. Kind of like a battery snow plow using the terminals to break up the snow. I've never seen such a mess.
We're gradually working some of the issues off this monster SUV, and my wife has curiously fallen in love with it, so I'm letting her drive it, but every time I see it lurching and careening down the road I wince.
In the case of the eCobra belly pans, they are enclosed. The cell terminals are actually quite distanced from the box walls. And in fact we have a piece of Weyerhauser Colorfast Deck to cover the terminals inside the box. This is a recycled plastic decking used for porches. It has enormous dielectric and of course physical strength. It's a little heavy for this purpose, but quite effective.
The boxes do have external terminals. We put a boot on them, but they are I guess open to the elements if placed underwater. I suppose we could do a placard DO NOT RACE THIS CAR IN FLOODED AREAS across the trunk. But I really don't know what would happen.
We do talk a bit about the OEM sales numbers. I've already been corrected by viewers who have accepted "spokesperson" numbers from the OEMs as being more accurate than mine. I don't know quite how to react. I am frankly skeptical of any company that HAS an employee who's title is "spokesperson". In many companies, the CEO is the "spokesperson" almost by definition. In those that have dedicated professional "spokespersons" there is actually a reason. They are very good at making barefaced lies look and sound very much like open truthfulness. That's why they were hired for the position. It's all a little circular.
EVTV has no "spokesperson."
So why have I adopted this anti-OEM position? First, I just don't like blatant dishonesty. It is annoying. And it's not effective. It puts a company in an adversarial relationship with their customer base. Not good.
But I see damage from this particular set of realities. First, the Nissan Leaf is by all accounts an excellent electric vehicle. The Volt is gasoline powered, but as best I can tell, a technological marvel and a pleasure to drive and own I am sure. I have NOTHING against these vehicles per se and do not denigrate the efforts of some obviously enormously talented engineers who created them.
The price/value proposition is a little vague. And that's a problem.
First, they are electric drive "conversions" in a sense. The Chevy Volt is essentially identical to the Chevy Cruze, but with the hybrid "range extender" drive train. The Chevy Cruze features a MSRP starting at $16,525 and gets 26 mpg city and 36 mpg highway. The Volt features an MSRP starting at $39,145 and claims 60 mpg. The problem of course being I could buy TWO Cruze models and still have $6075 left over, more than enough to buy gasoline for BOTH of them for about a year and a half. Oh, and I still have to buy gasoline for the Volt.
????? What kind of thing is this? Is there any wonder GM sold 24,648 Cruze's in July, and 125 Volts?
The spokesperson spin is just bizarre. First, Chevrolet is retooling to expand production to 60,000 units per year. But nearly a year ago they claimed they were expanding production capacity to 110,000 units per year. Like our Congress in reverse, Chevrolet is now professing a CUT of 50,000 units per year is an INCREASE. I need to hold a seminar on comparing numbers to determine which is larger and which is smaller. I think I could make a fortune just in auto executives and politicians.
GM actually sold 214,915 vehicles across the line in July. Volts of course comprising 0.0582 PERCENT of that total.
They also claimed that the Volts that were sold spend an average of 13 days at the dealers. Quite comical, this average does NOT include the Volts NOT sold. And there are plenty of them. A recent poll of Chevrolet dealers was discontinued after the researcher determined that ALL of the first few dozen he called indeed had Volts in stock awaiting drivers.
The "spokesperson" also claims they can sell all the Volts they can make. Of course they can. At some price. Some where. New cars just don't go "unsold" forever. They are disposed of in some manner or other eventually.
Why am I on about this? We are largely shaped by the perceptions of the public, which is largely shaped by the broader news media. The next shoe to drop is the "What Happened to the Electric Car" story. The same group of reporters touting all of this for years now will turn about face without a BLINK (they are kind of like Spokespersons in this regard) and seize on the story of the "bloodbath" in electric vehicle sales complete with stories on stranded motorists who just didn't make it home. Stay tuned. We are just weeks away from this.
And since it will then be proven irrefutably that American drivers do NOT want electric cars, we can move on to other tasks. The plans of automakers who didn't get to market so fast can be "extended" and eventually back benched so far as to be effectively removed from play. And producing no electric cars, we'll all sit back to await the fall in battery prices that will never occur because they won't be producing any.
A dark scenario. All over a car that was never truly electric.
By establishing the value of the Cruze in the market, and offering the Volt at over twice the price, what is the value proposition to a buyer? Very poor. So how is this a good example of an electric car? Not to speak of it's propensity to burn gasoline?
Won't matter. It is what it is. Complete with plausible deniability. "We tried."
This makes the ground harder to plow for any would-be participants including Tesla. But startups? The funding will dry up as if it were never there. Battery technology? Ditto.
This is REALLY most damaging. The higher the expectations, the more dashed the reality.
And in truth, these cars simply do not fit the business model of the automobile manufacturers. Nissan a year ago was braying like a donkey that they had the cost of the battery down to $9000. Last week they were quoted on a single module replacement in the UK at $682. As there are 48 modules in the pack, you are north of $31,000 replacement cost in a car priced at $32,768 - again roughly TWICE the cost of the identical car coming off the same production line that is NOT electric. This is an apparent 350% markup on the batteries. Guys, that is NOT an unusual markup by Mr. Goodwrench on an automobile part. And that IS part of their business model. Every fan belt, every filter, every spark plug, every gasket. It mounts up to a PILE of parts in the life of a car. And done at the dealership, it amounts to a HUGE amount of consumables and a lot of the profit in making the car.
Where is Tesla in all this. They're kind of a clean sheet of paper. But you will recall that at one point in their development, they were purportedly selling a two seat sports car for $109,000. The problem was it was costing them $146,000 to make each car NOT counting R&D. And there's no "consumable" downline except the battery pack. Most of the repair parts on the car would come from Lotus - whether or not you bought them through Tesla.
So they started over with the Model S. I believe that the people in this company truly believe in the electric car, and I have a deposit down on a Model S without even knowing what the pricing on the car is. Remarkably, 5600 other people have made the same leap of faith. But I have to wonder about the battery technology and what we do when they fail. A brand new $77,000 car with ZERO resale value? A $75,000 battery replacement cost? What?
In any event, the "early adopter" phase of electric cars would be marked in theory by a 2.5% market share. On our normal 15 million per year production, that's 375,000 cars per year. That's an achievable number. But it HAS to be made from cars that are appealing to early adopters. And $16,000 economy cars, complete with lipstick and high heels, just aren't.
It might be counterintuitive, and even ironic, but I CAN afford $77,000 for an advanced technology all aluminum frame electric car with a 19 inch display and seating for 7 in a European sedan. I CANNOT afford $42,000 for a Chevrolet Cruze. This is the heart of the "value proposition" of which I speak.
David Hrivnak drove his EMIS Avalanche from Kingsport Tennessee to our facility to show what he's done with this and make his case for his position as one of 10 finalists in the EVTV Build Your Dream EV contest. Unfortunately, while we did a complete walk around on this very interesting experiment, El BRAINO left the audio off on five walk around segments that are subsequently OMITTED from this week's show. My most sincere apologies to Mr. Hrivnak, who nonetheless did a great job describing the project.
The blizzard of surreal is not limited to the cars. There are announcements daily, a blizzard of press releases, and the most GORGEOUS images on the World Wide Web, of componentry and technology for electric cars that extend belief. Tragically, they either do not EXIST, are a heroically stupid idea, a solution in search of a problem or all the above in some combination. Unobtanium punctuated by unnecessary in many cases.
I LOVE the idea of inductive charging. Have since Nicolas first proposed it. I would love to have a highway system replete with it. I can see it in my mind. What I cannot see is it in my garage. A 10% efficiency penalty works out to 15 cents for the eight seconds it takes to plug in a cord. That's $67.50 per hour wage. If I offered a position for a qualified technician to go from garage to garage across the land plugging in cars, how many applicants would I get at $67.50 per hour? Answer: ALL of them.
Meanwhile, the very small scale tinkerers and innovators plug away in their garage, trying to get a 14 year old BMW to whisper into life and turn into a magic carpet. He thinks he's alone. And he's pretty sure it won't work. He's terrified of the batteries - their cost, their safety, and how to use them. He saved $2400 by not buying that hydraulic lift - already a serious mistake. The running gear and body is NOT quite in the shape he thought when he bought it. And he really doesn't have much of a plan about that air conditioner.
And most discouraging of all, there are all these REAL engineers out there with REALLY COOL stuff like $35,000 AC drivetrains, inductive charging, wheel motors, highly engineered battery modules, and THEY really know what they are doing and can make cars that would be REALLY cool. You want proof? You can see it on the web...
How am I supposed to respond to this? You see, in my world, this guy is a hero, Netgain actually sells motors, batteries are GOOD things, and a Federal budget CUT is a SMALLER number....
That's how VERY out of it I am.
We're going to put our head down, make cars that drive like magic carpets, and videos that have some SERIOUS audio problems. And we're going to keep doing all of that until we win. If it takes five years, I was hoping to live five years anyway. If it takes ten, I'll have to quit smoking and lose a few pounds..
Friday, August 5, 2011
Days of Wine and Roses
This week we welcome Mark Emon of St Michael's Maryland as our special guest. Mark operates St. Michael's winery and brought us an interesting Seyval/Chardonnay and an equally delightful Chambourcin.
I'm frankly not a fan of North American wine grapes and hybrids. I love to drive the Porsche to a local Missouri or Illinois winery for a bit of lunch and a bottle of vino, but generally you have to enjoy the drive and the view and the setting. The wine is rarely a treat.
But Mark's offering was actually pretty tasty and we polished off both bottles before we quite done shooting this week's show. So if we seem happier about the state of the electric car this week than the news quite merits, there you have it.
Mr. Emon is one of our 10 finalists in the EVTV Build Your Dream EV Components contest. Recall that we are giving away 50 CALB 180Ah batteries, a Netgain Warp 9 motor, an EVnetics Soliton 1 controller, a RechargeCar magnetic pickup, a Masterflux Sierra electric air conditioner and of course a case of Stag beer to the winner. We had offered the opportunity for finalists to come to Cape Girardeau and appear on the show to set their appeal, American Idol style, directly to the viewers and consequently the voters in this contest.
Mark is in the midst of converting a Porsche 914 Targa to electric and he took the opportunity of the visit to sign up for the Electric Vehicle Conversion Convention (EVCCON) tendering his registration fee noting that he is bringing his green Porsche 914 to the convention. A challenge as he has yet to complete it and it is his first conversion.
But he's already planning his second and kind of counting on winning the pile of loot to compete an experienced BMW for his wife to drive.
My simple demonstration of opening a box with a Thundersky battery in it that we had had on hand since October of 2008, manufactured in August of 2008, and measuring the open circuit cell voltage of 3.300 which precisely matched the 3.300v of the Thundersky 400Ah cells we received the day before. This cause quite a stir. There is an entire little army of pseudo poseur engineers over on the DIYelectricjunk forum immediately sprang into action spraying messages in all directions describing what I did and did not do, what I should of done, and why I had it all confused and totally incorrect.
What I found terribly interesting in this, beyond the sheer number of them and the intensity of their howls of outrage, was how MUCH they appeared to know about what I do and don't do in testing batteries. On reflection, while I find the entire concept of typing nonsense into the screen on topics you know absolutely nothing about both annoying and slightly nauseating, but the level of disconnect was a little jarring.
Partly my fault. I actually have a greater interest in battery technology than I quite do in automobiles. My father had a variety of not very good construction equipment rolling stock when I was a stripling and it rather fell to me, somehow, to maintain this rolling collection of wreckage - none of it young nor particularly appealing when it was. So the concept of "working on cars" for pleasure is not a thing I share with our viewership. I hadn't changed my own motor oil for 30 years when we began this mission.
Indeed, while I have long been fascinated by electric cars, I don't even count them as viable - until the advent of these batteries. So for me, it is ALL about the batteries, and from that, the cars, and extending further, a convenient solution to an inconvenient problem. ANd in fact, the more I look, the more problems I find, some really QUITE alarming, that simply adopting personal transportation that is seven to eight times MORE efficient at converting energy to forward motion essentially solves very neatly and very nearly completely.
Most problems are simply intractable and require a lot of chewing around the edges from a variety of directions to even steer toward a solution. Electric personal transportation really IS kind of a magic bullet. With a couple of admittedly ambitious assumptions, some of these problems simply evaporate.
This is something akin to banishing the U.S. national debt by banning turtle racing, and of course the insidious wagering on turtles that goes with it. Or curing cancer with T-shirts. Imagine if we could eliminate child abuse by simply backhanding mouthy kids? Or relieve traffic congestion by coughing a lot?
Or wipe out unemployment by buying more Chinese baseball caps.
For some pretty serious problems like the largest transfer of wealth every recorded in the history of the world, from the U.S. to the middle east, this one really IS that easy. Get 20% of the population to drive 20% of their miles in electric cars and the problem doesn't ease - it disappears entirely.
To avoid a devastating collapse of the global financial system caused by spiraling gasoline prices headed our way just a few years hence, same solution. And same result. It pretty much just goes away. Not a problem. Was a BIG problem. Now, no problem.
It even solves problems that AREN'T really problems. I guess I am a bit agnostic about global warming. But electric cars offer a partial solution even to this - a very convenient response at that. And I suspect that 300 million autos all huffing 60 lbs of atmosphere per gallon into a cloud of nitrous oxides, particulates, and carbon monoxide may well have something to do with currently popular and problematic diseases that just weren't heard of 75 years ago. The place would in any event be clearer, prettier, and not smell so bad.
So it's a very appealing situation. But it all derives from the batteries. And I do a lot of twizzling with these batteries. But I doubt that it makes very good video or would ever get me to go viral on YouTube. It's just something I like to do in the back room, and even the people on EVTV with me really don't know what I do back there, or why I go do that. So how do the chirping magpies lined up by the hundreds on the DIYelectric telephone line know so much about it?
Of course they don't. But that's partly my fault. I don't really video very much of it. So their suppositions of what I do and don't do and so forth are generated entirely in a vacuum, which doesn't explain how they come up with so MUCH of it. But enough about them, more about me.
The demonstration on camera was of course simplistic. It was made for video. It communicated the situation very clearly. We had just received a brand new shipment of Winston Battery Company 400 Ah cells. And I had some Thundersky 90 Ah cells from nearly three years ago still in the box. So I had one of our visitors from the Netherlands dramatically open the box and measure the open circuit terminal voltage of the cells, and compare them to the cells just received.
IT NEVER OCCURRED TO ME that the DIYenginiers did not even comprehend the relationship between voltage and state of charge. THAT's how lost we are in the conversation here.
But of course I had taken out cells numerous times over the three years, and measured the same thing, and checked exactly how many amp hours were in them and how much charge they would take and what charging to various voltages does and on and on and on. Who but me would care? How many ions can dance on the head of a pin really IS the question, but it has no easy answers and whatever I measure there is more to measure tomorrow. And all if it is terribly time consuming. It takes hours. I don't even want to watch all that.
In this episode we did at least do a simply test to show open circuit cell voltage after a too brief rest, and how it changes over the state of charge of the battery. Does it make perfect sense and operate very predictably? Absolutely. Would it make a good fuel gage? Not really. Can it be used as a fuel gage anyway? Yeah, kind of.
And of course, the cells have the same capacity and there is no cell drift, and no "balance" problems and so of course the magpies are enraged because most of them are working on Battery Management Systems in hopes of selling them and making a brazillion dollars on the EV "craze".
First, there's no craze. Lacking any concept of business at all, if they sold any they wouldn't make any money. But the thing they're working on nobody needs anyway. And that's a hard thing to face.
It all brings up a broader question we faced back in the early days of the Internet. I think it was Mitch Kapor of Lotus (smart guy, my goodness he was tough to even be in the room with) who likened it to 12 blind men surrounding an elephant. Each would feel up the elephant and argue vehemently with the guy next to him as to what it looked like.
The Nissan Leaf uses a Lithium Manganese Oxide battery. They actually call it Lithium Manganese Spinel because the term oxide is almost perforative with regards to thermal safety issues. GM uses a slightly different manganese oxide cell from LG chem.Tesla actually uses a Lithium Cobalt Oxide battery, probably with a nickel current collector. We use Lithium Iron Phosphate cells from CHina.
There are several reasons NOT to use Lithium Iron Phosphate cells from China. In the past, they have not been very consistent in their manufacturing process. Second, they are most commonly available in these largish prismatic battery cells we use. This is kind of a "commodity" approach to batteries like your standard AA battery that is ubiquitous in small electronic devices. There is no way to really have a "proprietary" battery technology with AA cells. And of course, you have to communicate in Chinglish, wait 12 weeks for your cells, and the whole business model is just a mess. Dozens of "trading companies" all claiming to own factories they don't own, technologies they don't own, and market them in a language they're not at all familiar with. And the very basic issue of energy density OR power density is slightly LESS in LiFepo4 chemistries.
So I know of NO OEM who has even LOOKED at these cells. Never were on the table. I see absolute awe and worship in the body politic of electric car users over the "laboratories" at General Motors and Nissan and Tesla. WHile it is not in their economic interest to dispel this myth, there is no magic behind those doors. And they certainly aren't going to spend a lot of time looking at a slightly LESS effective chemistry that they can't use to create a proprietary pack anyway. Again, this stuff takes HOURS, and DAYS, and WEEKS, and MONTHS, and then YEARS to test even to the basics. You can automate it and speed it up to a very minor degree, but not really.
So it occurs to me, if the level of understanding of these cells is SO VERY POOR within our own community of people who actually do buy them and use them, and we couple this with the very natural propensity of OEM's to maintain a level of trade secrecy about their "magic sauce" which must be the batteries, we have a perfect storm. A total VACUUM of knowledge about current lithium ion cell technology. A perhaps PERFECT VACUUM. Picture 2800 deaf dumb and blind men about an elephant who don't even CARE what it looks like, they just are certain the guy next to them is a moron because he neither speaks, hears, nor sees.
Gotta love it. But after several years of studying almost entirely the LiFePo4 Chinese cells, and in truth with very LITTLE knowledge of the oxide chemistries (and even less interest frankly), I am slowly coming to the conclusion that we have accidentally stumbled on the very best cell technology for electric cars, and our good fortune was entirely driven by the REFUSAL of anyone else to sell us cells. These little bricks are REMARKABLY durable. They will suffer ANYTHING and put out IMMENSE levels of power from a simple stack of aluminum and copper foil no more complicated than a book. You simply have to observe TWO rules of thumb that are QUITE absolute. You CANNOT overcharge these batteries. And you CANNOT over discharge them. And if you observe these two, they most likely will last FOREVER, and suffer any indignity with absolute charm. And none of the OEM's are even aware of them.
Peter McWade sent me two elderly HiPower cells this week. Not my favorites anyway, he claimed these were abused. They were wonderful. Still OVER their 100AH spec and going strong. One was totally discharged. One was totally charged. I don't know if this was a test of the cells or some sort of bizarre test of Jack. But I marveled anew at how even the worst of these LiFePo4 cells are just very very good.
Jack RIckard
I'm frankly not a fan of North American wine grapes and hybrids. I love to drive the Porsche to a local Missouri or Illinois winery for a bit of lunch and a bottle of vino, but generally you have to enjoy the drive and the view and the setting. The wine is rarely a treat.
But Mark's offering was actually pretty tasty and we polished off both bottles before we quite done shooting this week's show. So if we seem happier about the state of the electric car this week than the news quite merits, there you have it.
Mr. Emon is one of our 10 finalists in the EVTV Build Your Dream EV Components contest. Recall that we are giving away 50 CALB 180Ah batteries, a Netgain Warp 9 motor, an EVnetics Soliton 1 controller, a RechargeCar magnetic pickup, a Masterflux Sierra electric air conditioner and of course a case of Stag beer to the winner. We had offered the opportunity for finalists to come to Cape Girardeau and appear on the show to set their appeal, American Idol style, directly to the viewers and consequently the voters in this contest.
Mark is in the midst of converting a Porsche 914 Targa to electric and he took the opportunity of the visit to sign up for the Electric Vehicle Conversion Convention (EVCCON) tendering his registration fee noting that he is bringing his green Porsche 914 to the convention. A challenge as he has yet to complete it and it is his first conversion.
But he's already planning his second and kind of counting on winning the pile of loot to compete an experienced BMW for his wife to drive.
My simple demonstration of opening a box with a Thundersky battery in it that we had had on hand since October of 2008, manufactured in August of 2008, and measuring the open circuit cell voltage of 3.300 which precisely matched the 3.300v of the Thundersky 400Ah cells we received the day before. This cause quite a stir. There is an entire little army of pseudo poseur engineers over on the DIYelectricjunk forum immediately sprang into action spraying messages in all directions describing what I did and did not do, what I should of done, and why I had it all confused and totally incorrect.
What I found terribly interesting in this, beyond the sheer number of them and the intensity of their howls of outrage, was how MUCH they appeared to know about what I do and don't do in testing batteries. On reflection, while I find the entire concept of typing nonsense into the screen on topics you know absolutely nothing about both annoying and slightly nauseating, but the level of disconnect was a little jarring.
Partly my fault. I actually have a greater interest in battery technology than I quite do in automobiles. My father had a variety of not very good construction equipment rolling stock when I was a stripling and it rather fell to me, somehow, to maintain this rolling collection of wreckage - none of it young nor particularly appealing when it was. So the concept of "working on cars" for pleasure is not a thing I share with our viewership. I hadn't changed my own motor oil for 30 years when we began this mission.
Indeed, while I have long been fascinated by electric cars, I don't even count them as viable - until the advent of these batteries. So for me, it is ALL about the batteries, and from that, the cars, and extending further, a convenient solution to an inconvenient problem. ANd in fact, the more I look, the more problems I find, some really QUITE alarming, that simply adopting personal transportation that is seven to eight times MORE efficient at converting energy to forward motion essentially solves very neatly and very nearly completely.
Most problems are simply intractable and require a lot of chewing around the edges from a variety of directions to even steer toward a solution. Electric personal transportation really IS kind of a magic bullet. With a couple of admittedly ambitious assumptions, some of these problems simply evaporate.
This is something akin to banishing the U.S. national debt by banning turtle racing, and of course the insidious wagering on turtles that goes with it. Or curing cancer with T-shirts. Imagine if we could eliminate child abuse by simply backhanding mouthy kids? Or relieve traffic congestion by coughing a lot?
Or wipe out unemployment by buying more Chinese baseball caps.
For some pretty serious problems like the largest transfer of wealth every recorded in the history of the world, from the U.S. to the middle east, this one really IS that easy. Get 20% of the population to drive 20% of their miles in electric cars and the problem doesn't ease - it disappears entirely.
To avoid a devastating collapse of the global financial system caused by spiraling gasoline prices headed our way just a few years hence, same solution. And same result. It pretty much just goes away. Not a problem. Was a BIG problem. Now, no problem.
It even solves problems that AREN'T really problems. I guess I am a bit agnostic about global warming. But electric cars offer a partial solution even to this - a very convenient response at that. And I suspect that 300 million autos all huffing 60 lbs of atmosphere per gallon into a cloud of nitrous oxides, particulates, and carbon monoxide may well have something to do with currently popular and problematic diseases that just weren't heard of 75 years ago. The place would in any event be clearer, prettier, and not smell so bad.
So it's a very appealing situation. But it all derives from the batteries. And I do a lot of twizzling with these batteries. But I doubt that it makes very good video or would ever get me to go viral on YouTube. It's just something I like to do in the back room, and even the people on EVTV with me really don't know what I do back there, or why I go do that. So how do the chirping magpies lined up by the hundreds on the DIYelectric telephone line know so much about it?
Of course they don't. But that's partly my fault. I don't really video very much of it. So their suppositions of what I do and don't do and so forth are generated entirely in a vacuum, which doesn't explain how they come up with so MUCH of it. But enough about them, more about me.
The demonstration on camera was of course simplistic. It was made for video. It communicated the situation very clearly. We had just received a brand new shipment of Winston Battery Company 400 Ah cells. And I had some Thundersky 90 Ah cells from nearly three years ago still in the box. So I had one of our visitors from the Netherlands dramatically open the box and measure the open circuit terminal voltage of the cells, and compare them to the cells just received.
IT NEVER OCCURRED TO ME that the DIYenginiers did not even comprehend the relationship between voltage and state of charge. THAT's how lost we are in the conversation here.
But of course I had taken out cells numerous times over the three years, and measured the same thing, and checked exactly how many amp hours were in them and how much charge they would take and what charging to various voltages does and on and on and on. Who but me would care? How many ions can dance on the head of a pin really IS the question, but it has no easy answers and whatever I measure there is more to measure tomorrow. And all if it is terribly time consuming. It takes hours. I don't even want to watch all that.
In this episode we did at least do a simply test to show open circuit cell voltage after a too brief rest, and how it changes over the state of charge of the battery. Does it make perfect sense and operate very predictably? Absolutely. Would it make a good fuel gage? Not really. Can it be used as a fuel gage anyway? Yeah, kind of.
And of course, the cells have the same capacity and there is no cell drift, and no "balance" problems and so of course the magpies are enraged because most of them are working on Battery Management Systems in hopes of selling them and making a brazillion dollars on the EV "craze".
First, there's no craze. Lacking any concept of business at all, if they sold any they wouldn't make any money. But the thing they're working on nobody needs anyway. And that's a hard thing to face.
It all brings up a broader question we faced back in the early days of the Internet. I think it was Mitch Kapor of Lotus (smart guy, my goodness he was tough to even be in the room with) who likened it to 12 blind men surrounding an elephant. Each would feel up the elephant and argue vehemently with the guy next to him as to what it looked like.
The Nissan Leaf uses a Lithium Manganese Oxide battery. They actually call it Lithium Manganese Spinel because the term oxide is almost perforative with regards to thermal safety issues. GM uses a slightly different manganese oxide cell from LG chem.Tesla actually uses a Lithium Cobalt Oxide battery, probably with a nickel current collector. We use Lithium Iron Phosphate cells from CHina.
There are several reasons NOT to use Lithium Iron Phosphate cells from China. In the past, they have not been very consistent in their manufacturing process. Second, they are most commonly available in these largish prismatic battery cells we use. This is kind of a "commodity" approach to batteries like your standard AA battery that is ubiquitous in small electronic devices. There is no way to really have a "proprietary" battery technology with AA cells. And of course, you have to communicate in Chinglish, wait 12 weeks for your cells, and the whole business model is just a mess. Dozens of "trading companies" all claiming to own factories they don't own, technologies they don't own, and market them in a language they're not at all familiar with. And the very basic issue of energy density OR power density is slightly LESS in LiFepo4 chemistries.
So I know of NO OEM who has even LOOKED at these cells. Never were on the table. I see absolute awe and worship in the body politic of electric car users over the "laboratories" at General Motors and Nissan and Tesla. WHile it is not in their economic interest to dispel this myth, there is no magic behind those doors. And they certainly aren't going to spend a lot of time looking at a slightly LESS effective chemistry that they can't use to create a proprietary pack anyway. Again, this stuff takes HOURS, and DAYS, and WEEKS, and MONTHS, and then YEARS to test even to the basics. You can automate it and speed it up to a very minor degree, but not really.
So it occurs to me, if the level of understanding of these cells is SO VERY POOR within our own community of people who actually do buy them and use them, and we couple this with the very natural propensity of OEM's to maintain a level of trade secrecy about their "magic sauce" which must be the batteries, we have a perfect storm. A total VACUUM of knowledge about current lithium ion cell technology. A perhaps PERFECT VACUUM. Picture 2800 deaf dumb and blind men about an elephant who don't even CARE what it looks like, they just are certain the guy next to them is a moron because he neither speaks, hears, nor sees.
Gotta love it. But after several years of studying almost entirely the LiFePo4 Chinese cells, and in truth with very LITTLE knowledge of the oxide chemistries (and even less interest frankly), I am slowly coming to the conclusion that we have accidentally stumbled on the very best cell technology for electric cars, and our good fortune was entirely driven by the REFUSAL of anyone else to sell us cells. These little bricks are REMARKABLY durable. They will suffer ANYTHING and put out IMMENSE levels of power from a simple stack of aluminum and copper foil no more complicated than a book. You simply have to observe TWO rules of thumb that are QUITE absolute. You CANNOT overcharge these batteries. And you CANNOT over discharge them. And if you observe these two, they most likely will last FOREVER, and suffer any indignity with absolute charm. And none of the OEM's are even aware of them.
Peter McWade sent me two elderly HiPower cells this week. Not my favorites anyway, he claimed these were abused. They were wonderful. Still OVER their 100AH spec and going strong. One was totally discharged. One was totally charged. I don't know if this was a test of the cells or some sort of bizarre test of Jack. But I marveled anew at how even the worst of these LiFePo4 cells are just very very good.
Jack RIckard
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