Pretty good show this week. Fred Behning of Austin sent us a nice video walkaround of his still in progress conversion of a 1960 Bug-Eye Sprite in all it’s blazing yellow glory. This is the kind of upscale quality build of a much loved classic that I am so fond of. For my money, he has enough motor, controller, and batteries in this thing for about 2 1/2 Sprites. But I think it will go Spritely once completed.
It is coming to light that my prediction of a blood bath for General Motors and for Nissan was prescient. Neither are selling in anywhere near the numbers they had hoped. Both companies are spinning this heroically by the day as the truth becomes apparent to all. General Motors particularly simply readjusts reality in print – it has reached the level of absurd.
My take is that the value proposition on economical electric cars cannot be made, and so we should focus on high end cars that appeal to early adopters. But I’ve been aware all along that there is a latent desire/demand from those already in the green and electric camp for a viable option. My predication is based on the fact that once that demand is met, THEN who do you sell them to. And just how large a group is this vocal but probably small band.
What I didn’t count on was the fact that our viewers are actually the band. Fred Behning awaits delivery of his Leaf. Peter McWade already has his. And a dozen other viewers are in some form or fashion awaiting one of these cars. More so the Leaf than the Volt. Though recall the recent fire of a Volt in a garage – fixing blame was complicated by the fact that he also had a converted Suzuki in the garage at the time.
WE may be the market for these cars. Unfortunately, there is probably not enough WE in WE. But again, gradually as you demonstrate the advantages of electric cars, this will take hold beyond what you realize. You have an impact daily.
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Meanwhile, we are in the throes of a fistfight with a Cobra replica. I was initially amazed at how much room I had for batteries. I’m now a little bewildered by how little. The choice of the 11HV leads us to higher voltages, but we still want to be able to make very high currents as well. We’ve run smack up against the very old and oft quoted EV maxim: You can have range, speed, or price. Pick any two.
In this case, we want range and speed. And the restrictions of gravity and force and inertia are wreaking havoc on my ambitions. But in a way, this project kind of “lets the dog out” in me. We’re going to find where it goes. But as usual, battery layout and placement are 90% of the project. Drive train being another 90% and of course wiring and instrumentation represent the final 90%. Due to rounding errors, this may not add up to exactly 100%.
We’ve decided on Thundersky 90Ah cells for our project. And therein lies a tale. We have the THundersky’s in hand but there have been some developments that are a bit soap opera-ish. Winston Chung Hing Ka of course founded Thundersky and developed the originally battery himself. I relocated my battery lab this weekend and am doing some testing now that reminds me how much I admire this cell chemistry. It is just incredible in so many ways.
Apparently there was at some point an IPO at Thundersky because it is traded on the Hong Kong Exchange HKG:0729. This of course leads to disclosure, like the US. The company posted a loss of HK$1.06 billion on sales of HK$69.43 million for the six months ended September 30, 2010. When you factor out the exchange rates, one of the interesting things about the company is a total of less than $10 million USD sales for that period This was up dramatically from $1 million in the same period of 2009. And that brings us to a startling revelation. We are the entire market for these batteries. At $10 million, that’s about enough batteries for 1000 very basic car conversions. At $1 million a year earlier, about a 100. I’ve suspected this for some time. YOU are the market for these cells. All allusions to big projects and OEMs is pure grade B refined bullshit.
Prior to February 22nd, Chung held 79.25% of the stock – an exceptionally high amount of equity in a publicly traded company here in the U.S. He sold about 30 million shares on February 22 and 23rd, 50 million shares on April 29, and 910 million shares on May 3, dropping his ownership to 43%. The majority investors subsequently fired him and have filed a lawsuit over 15 patents it claims it holds through a subsidiary purchased the previous May in 2010.
Meanwhile, Chung used the proceeds to launch Winston Battery Company Ltd., and acquired 48% of Balqon.
Thundersky is facing huge losses in 2011, as Chung apparently took most of the sales with him as well. Thundersky has renamed itself the Sinopoly Battery Company.
Now one of the interesting things about THAT is that one of the factories retained by Sinopoly makes the 200Ah Thundersky cell – not the new Yttrium cell apparently but the earlier LiFePo4 cell. And one of the interesting things about THAT is it is in the 71mm format that previously had been 160Ah cells – and at the same weight of 5.6kg. So in this one specific size and weight, we have the TS-160Ah, the CALB 180Ah, and the TS-200Ah cell.
We had tested these cells last year and they performed very well. So well that we PURCHASED 40 of them from James Morrison/David Kois. They kept the money, and never sent the cells. So we’ve never really been able to use them. After a year of wrangling, the lawsuit was settled and some recovery of inventory was made from Morrison – estimated at 59% of what the group had purchased. The 200Ah cells were among them, but not a sufficient number for the guys who ordered cells to actually receive them.
Now Sinopoly is apparently offering them – Meanwhile, we’re assured by Winston that they do NOT offer this cell.
In any event, that’s not the cell we’ve selected for the Cobra. We’re using the 90Ah cell which has been reduced somewhat in physical size. And we’ve decided that we need 180Ah in order to do 1000 amps and beyond. So we’re doing something I’ve wanted to do for some time = pairing smaller cells to get larger Ah capacities.
Recall that cells vary somewhat in capacity and you would have an easier time with your pack if all cells were the same capacity. In truth, there is no such thing as “cell drift” with these cells because they do not have any internal discharge. But they do vary in capacity. And you are only as long as your shortest cell.
By pairing cells, we could balance all this out. We would naturally want to pair the largest cell (say 94 AH) with the smallest cell (say 89AH), for a total of 183Ah. We would then match the NEXT largest cell with the NEXT smallest cell, and so forth. In this way, the variance between cells is drastically reduced.
That would require us to know the capacity of each individual cell. I wish they came marked. To actually test each cell would require months of effort. But we get some of the effect by just randomly pairing them.
For future reference, this technique works with two cells, works better with three cells, works better yet with four cells, etc. After about 10 cells, it is really subject to the law of diminishing returns. It doesn’t improve much after that. We have plans for this bit of knowledge.
But for now, we are going to pair the cells to get what amelioration we can from the capacity difference problem. The problem then becomes, to get 240v, which is what I would like to have for the 11HV, requires 144 cells. 72x 3.35 = 241.2v. This would give us a pack of 43,416 watt-Hours. At about 280 watts per mile, this would give us a max range of 155 miles. But even in this smaller and therefore more granular form factor, 144 cells is a LOT of cells. The most we’ve done has been the Mini Cooper with 112.
In the video, we also introduce the concept of watts per pound. We have Speedster Redux to thank there. We know we sagged about 22% to 147 volts at 1000 amps using 180 Ah cells. This works out to an input power of 66 watts per pound of the 2385 lbs of Speester weight resulting. The Cobra is going to be a heavier car, perhaps 2800 lbs. And so we would need a 215 volt pack to maintain the same power to weight ratio and so the same 6.5 second 0-60 time. And so I view 215 volts as the minimum and 240 volts the maximum we could get into the car.
As to performance, we do have a couple of kickers in the foot locker to put into play. First, our transmission is FIVE speeds instead of four. We’re going to go to a 4.11 limited slip differential on this beauty which should bring it clawing and scratching up out of the hole in fairly persuasive fashion.
And one of the reasons we can do this is that I think the 11HV at the higher voltage will let us move our peak power point out from 3200 rpm – perhaps out as much as 4000 rpm.
Finally, we are looking at controllers that do signficantly MORE than 1000 amperes for a top end.
When we put all that together, I’m starting to get enthusiastic about this car. Brain says the mission with Cobra’s is pretty simple: the cars you see in the rear view mirror should always be shrinking in size at an impressive rate. I think we can do that. But it will be interesting to see what we blow up along the way.
42 thoughts on “Of Sprites and Cobras and Meetings in the Fall”
Hello Jack et al,
So I’ve finally registered for a Blogger account to enable leaving messages on your comment board. I’ve been silent since you disabled the anonymous commenting in past blogs. I now have one more logon and password to eventually forget. 😉
In your Cobra build, battery-box edition I was wondering why you are not using the battery compression straps to keep the batteries squeezed to prevent swelling type failure? I’m unsure if there actually is a “lack of squeeze” failure for these LiFePO4’s but that’s what I hear on the message boards. Manufacturer spec sheets and manuals are inconclusive.
The build is looking good & here is to getting the rest of the pack’s to fit!
With a build like this I’m wondering why you don’t go with a higher power cell like Headways, they don’t come in at the same price as A123’s so it’s a bit easier on the budget, but you can pick a voltage, I would suggest around 300 nominal before sag. Then pick a cell that is comfortable to work with, 10ah/12ah/16ah… Then decide on the range you want to determine the size pack required. If you buy direct from china the price is only a bit more than what I’ve seen for thundersky’s and you end up with a pack with enough power but WITHOUT the extra weight you are building into this car. It’s a lightweight high performance car, don’t load it up like a lead acid S10. If anyone has direct experience it should be you who knows that loading more batteries in a car doesn’t make it faster….. you learned that the expensive way.
assuming 280wh/mile as you have been using you need 28kw for your 100miles at 100%, bring that down to 80% and you are around 33.6kw at 300v that’s 112ah or 7 parallel 16ah cells. Depending on how you measure you’d be in the range of 89-91 series cells to make the voltage. From what I can see on the net each cell is 500grams, so using 90 series and 7 parallel you have 630 cells with a total weight of 693lbs plus connectors. Using even 75 series pairs of 90ah cells gets you in the 1000lb range with less voltage and power. The headway pack would be capable of 1120A continuous and 1680 peak (great for a 1400A controller) get you the range you want and shave hundreds of pounds off the final weight of the car… making it faster and more efficient. And the kicker…. 112ah’s of Headways is cheaper than 180ah of TS.
Based on your formulas my Porsche 944 will have 86.6 watts per pound… (260kw after sag) in a 3000lb car. If I could get my hands on the A123’s for less than 2 arms and a leg I would have 96.x watts per pound. You are a smart guy Jack, and obviously capable of some calculations, branch out from your comfort zone and have a look at some different batteries. TS are great cells, just not in a Cobra.
Good luck, I can’t wait to see the results.
I don’t know about the Volt but the LEAF is obviously supply constrained, not demand constrained. You may remember that Japan recently suffered an unprecedented natural disaster. Hard to say a product is not going to be successful when the units are mostly sold out before they are even built. The LEAF is only available in very few markets with a long wait time. Most people who might want a LEAF can’t even buy one in their area. We’re still a long way off before we can make any realistic claims as to the eventual success or failure of the LEAF.
Wow. Brought out ALL the battery experts AND a marketing guru. Great.
First, TS cell swelling. We have long since ceased using the pack restraints. The cells swell on two occasions, overcharge, overdischarge. We avoid both. And no problems. Bu they can be just as “constrained” in an aluminum box as with the strappping.
Robin – I’ve never seen such a jumbled bunch of calculations. We have tested headways. They didn’t even make it into the show. Not happening.
JP. You’re reading too many press releasees. They are spinning it as hard as they can but it is gradually coming to light. They’ve admitted their 20,000 deposits have dropped to 11,000 and the “demand” has dried up. There are still a few out there with cars on order who haven’t received them, but the 150,000 per year just isn’t happening and reality is starting to sink in.
Both companies are spinning this to absurd levels. But hte monthly sales pretty much tell the tale.
Here is a pretty good summary of the sales for each.
LEAF deliveries kept getting postponed and some people didn’t want to keep waiting. I don’t know, it doesn’t seem that surprising to me. Until we have unsold LEAF’s sitting on the lots it’s hard to say there is no demand.
On another note DBM seems to be delivering more cars for real world testing and their secret ingredient may be Vanadium.
Actually it’s easy to say. It’s hard to ultimately be correct. We’ll see. If it was all cool, we wouldnt’ see them spin it so hard.
DBM is unobtanium but very interesting. This is the first I’ve heard of their use of Vanadium.
I was wondering if voltage affects watts per mile? So by increasing your voltage the watts per mile drop. Say you have a 60ah 200volt pack vs 100ah 120volt pack. Would the watts per mile be the same?
Hi Jack – I am sure you guys have done your math on the pack configuration but I would be curious as to why you would limit battery voltage to 240V on a motor rated for 288V. With any appreciable sag, this setup is likely to leave quite a bit of top-end room and underutilize the motor. For our BMW conversion, we are going with HV11 and 340V 100AH pack – it will sag to ~290-300V at 1000A which will be right where I’d want it to be to get the most out of the motor. Am I missing something?
not really. still takes the same energy to move the car at certain speed. The only variable you might have is the efficiency of your motor and controller. Higher voltage generally means lower losses in controller and perhaps motor due to lower I^2*R and I*deltaV on the IGBTs. But this is like 2-3% max.
Here in the UK they have dropped the Leaf’s asking price by £1,000 to £24K.
After reading successive reports of the newer headway cells being of much higher quality than the older versions I have fantasized using their 60V,50AH (2’x4″x6″@~66lbs) packs that are made for motorcycles because they could be added in parallel to match my needs.
I can’t for the life of me call them higher power cells. They do have higher C rates for those that like to abuse them but that is simply because they are smaller and coil wound. There is still that niggle of doubt with quality. Repeatability of cell internal resistance and capacity in manufacturing is important. The bigger TS type cells now seem to offer this.
Voltage has no effect on watts per mile that I’m aware of. Your AH per mile will go down as your voltage goes up, and in precise ratio to maintain the SAME watts per mile. Watts per mile is more a function of weight than anything and we almost always see about a 9-11 to 1 ratio there.
A 2400 lb car will require 240 watts per mile. A 3500 lb car will require 350 watts per mile. In this case – a 2800 lb car iwll require 290 watts per mile.
Of course this is a rule of thumb. But I’m surprised how close it gets us time after time.
240 volts, 180Ah and the meaning of the universe. I would not likely do 340 volts. But I could easily be persuaded to do 280. The problem is purely physical. All that room I thought I had in the Cobra is quickly evaporating.
With all the TS bashing and headway worship, we find these cells really quite remarkable. I have a constant current load and we are just now testing this after seeing it graphically on the dyno. We can do 5-6 C from these cells for minutes at a time. But to do 1000 amps, we really need that 180Ah width. I’d like to be at 270Ah. of course.
But it’s a tradeoff. 240 volts at 180Ah is 144 90Ah cells. 280v requires 166. I just need room for 22 more cells. But I don’t have the 144 in yet.
To get 120 safe miles at 80%, we need 150 miles. 150 x 290 is 43500. 43500 / 180 is 241 volts.
And so it goes. Weight, range, power, voltage, acceleration. Yes, the motor can do higher voltage, and the controller can do higher current. It’s ok to NOT max your components to the absolute limit by the way. A little headroom is never a bad thing.
There is only so much room for aluminum and copper foil in a car. I like rectangular bricks as they can be stacked. Cylinders wind up mostly space and connectors. Headways will leave me short on EVERYTHING except perhaps instantaneous current which I really don’t have a problem with.
To do 340volts, I would need a BMW just to haul all the batteries around….
Ok, so still not sure on this one.
I understand it still takes the same energy to move the car at certain speed.
But I know that a higher voltage draws less amps to move the car at that certain speed. So if you have more voltage you should not use the ahs up as fast.
What I’m getting at is you can go the same distance with a smaller ah pack at higher voltage as a larger ah pack at lower voltage as long as the packs weigh the same.
So this would have to change the watts per mile. Correct?
I almost decided to not buy the Leaf because of delays. If the delays had been much longer I would have backed out. But since they did keep me updated to delivery in a timely manner I was still wiling to go through with the decision. I am glad I did. Very nice vehicle. It is also interesting that we have two others where I work that are going to be buying one and neither knew of my purchase. Neither are on the forums and they only saw them on TV. Now that is pretty cool. Others are out there that do want them. Delays will hurt the sales. I can’t say about long term sales but I do know I have mine and really like the car. I am still moving forward with our DIY cars so it will not stop the building or converting to electric at home.
So yes, Jack is most likely correct but I think there will be some benefit of some electric cars coming from the OEM’s again. I think it will allow some who can afford to buy one vs building one. There are many who can’t or don’t have the time to build one but can buy one and want one. These are the folks that will do so.
World shattering? No. Limited market? Yes. Will it change? Yes. When? Who knows.
The relationship is pretty simple, current times voltage equals power.
10 amps, 100 volts, 1000 watts.
100 amps 10 volts 1000 watts.
1000 amps, 1 volt, 1000 watts.
As you can see, if your voltage goes up, the current goes down. So yes, as you increase voltage, your AH requirement goes down for the same mile. But the power doesn’t change. You put 1000 watts in, and 850 of them move your car. The rest are given off as heat and noise.
Yeah, I kind of know how the OEM thing is going to come out. ANd yes, it is our own viewers who ARE the low hanging fruit. THere are some others. And it will be interesting to see what the numbers are. But this is playing out in front of you. You saw their projections and their numerical claims. And those are being rather dramatically updated at the moment and a serious spin being put on it.
The months will wear on and the reality will become apparent. By this time next year, the outcome will be very plain to see.
Can it grow from there as people experience the cars? Yes, but slowly. When you’re invested in doing 150.000 per year, 10,000 per year is an awful pill to swallow. That it grows to 15,000 the next year doesn’t make it much better.
In the Internet days we called this “Scale up or die.” The concept is that ANYTHING that succeeds can always be scaled up, no matter how daunting the scaling problems might appear. But the corollary was that NOTHING can be scaled down. After you’ve sunk $10 million into something to deal with 100,000 users, and only 2400 showed up, there is nothing that can be done to repair the situation and get the $10 million back – even if you grow it to 3000.
The SAME result on a $100K investment would lead to partying like a rock star.
Collectible Tesla Roadster?
Yes and no. 2400 cars sounds like a pittance but its actually a lot for an expensive niche collector car. It took Ferrari more than 15 years of production to make its 2400th car.
I think of the Tesla much the same way as the Acura NSX- a capable exotic with a small following that’s cheap for what it offers. There are about 3 times as many NSXs out there as Tesla Roadsters, and they haven’t really fared well on the used car market, despite being outstanding daily-driver capable cars with great ongoing factory support.
Even if Tesla can pace Honda with the enduring vehicle quality and support commitment to its first sports car, the Tesla is headed for a long rocky trough at the bottom of the value cycle. Excellent used cars already trade under $70k now.
Finding one with low miles and gentle use will be very easy for a long time. Sure, every museum will ultimately have one, but that still leaves 1500 cars with 300-cycle battery pack life looking for a home every three to five years. I predict that daily driven cars with tired packs will slip below $50k within a couple of years. That’s a great value for what it is- not quite as good a value (or a car) as an NSX for $35k, but a cool toy cheap- an OEM screamer for less than a top-shelf conversion would cost.
Buy a new pack, wear that out for 2-4 years, and pass the roadster on for the same $40-$45k. Great way to play, but there’s a pretty thin audience for that kind of autotainment, so it will remain a relatively inexpensive gambit. That’s the market outlook I see for this Tesla model. Its historical significance just isn’t going to create any value upside from there for a long, long time.
The big question is whether guys fall in love with the cars, keeping them “forever”, so they don’t trade through the stables of collectors like most cars (including the NSX) do. That would put a floor under prices, (provided there were a LOT of keepers,) and help the Tesla Roadster climb up the other side of the value trough about the time EVs really catch on- probably more than a decade from now.
For the month of June the LEAF sold more units in the US than the Honda Insight or the Honda CRZ or the Honda Civic Hybrid.
So here we have a brand new EV beating out some conventional hybrids. If you go to the LEAF forums you’ll quickly see that most owners are not DIY types. We’ll have to see how it plays out but so far I’m not seeing the evidence of Jack’s theory.
Tom, one aspect of future Roadster value you are ignoring is the car can actually improve with age as battery technology improves. At the very least range can increase so you’ll have a limited production historical EV with better range, and possibly better performance, than the original.
“…the car can actually improve with age as battery technology improves…”
JP – you beat me to the keyboard: yes indeed. I five years time a $1500/600 mile range battery pack upgrade kit for a run out Tesla would be rather in the tradition of the after-market bits for the small block Ford and Chevy V8s that first saw the light of day 50+ years ago
I doubt we’ll see that sort of improvement in 5 years, probably not ever frankly, but there will certainly be significant improvement as time goes on.
Tesla has patented some rather ordinary battery connectors apparently specifically to preclude 3rd pa try modules
Dielectric grease. Is it missing from your battery connections? Moisture and oxygen can still get under your once shiny contact areas and cause oxidation of the copper and aluminum. You need to eliminate the moisture or the oxygen or both to keep the contact points oxide free. Dielectric grease dose that. It also lubricates the threads so that more of the torque used to tighten the bolt goes into compressing the connection instead of overcoming friction / gulling of the threads. I work with a fellow who use to be an inspector for a telco. One thing he had to check for was grease oozing from the hole in the end of the terminal crimped to the end of battery cables used in telco back-up battery rooms, a step beyond just greasing the connection to the battery. Certainly your prismatics don’t ooze corrosive liquids and gasses but the oxides you scrub off will return with time, from normal moisture in the air and condensation, if not protected. I often use whatever grease I have around but for high currents I’d stay away from any grease that might burn. I think most dielectric grease is silicone based.
Humm, how about a small plasma ball just inside the side-pipes on the Cobra? I’ve seen them as small a 3″ on eBay.
Side pipes, connected to a bass bin or replaced with perspex tubing for a light display?
I’m sure the cars recipient will have his own wants and idea’s.
Because Tesla submitted such a patent as you say Jack then it might come to be that Tesla will sell new or rebuilt standard packs in the future.
Forgive me if I’m wrong but isn’t a dielectric grease basically an insulating grease *sometimes* with silica glass beads in it to maintain separation? It’s certainly not MOD or aircraft practice.
In the case above most likely used to keep clean the micro gaps not affected by the crimping. I wouldn’t use it on bolts and bus bars where the area is higher and the pressures relatively lower. Rather seal the battery box(es) with a couple of bags of desiccant. Like a Tesla?
I have a question that has no relation to this episode but thought i would post it here out of fear of no one seeing it if i posted it to an older episode.
My question is regarding the mounting the motors to the gear box on the Escalade. My understanding of an automatic gearbox is very limited to say the least and my knowledge on EVs is not much better.
But could the automatic gearbox be mounted to the motors without the torque converter? In the same way that some people elect not to use a clutch in a regular gearbox? Maybe the question should be, how important is the torque converter in changing gears as it is no longer needed for letting the motor idle without stalling?
I’m sure this is an obvious answer to most, but on the upside its always the stupid questions that get the most and often fastest answers.
Yes there are ways to eliminate the torque converter and people have done so.
KansasEV is out of business, or never was in business, or something. I can’t find a single unit ever put in service.
The reason a Powerglide works so well “clutchless” e.g. without a TC, is that its a two-speed (one changing gearset) planetary design, which can be shifted up or down under load without hurting it. Oval track racers have been using the PG this way for years.
With a 3 speed like a Turbohydramatic or Torqueflite from the 1960s, its a little more complex, and the friction components used inside the trans won’t hold up to a solidly fixed input. They all need a fluid (or maybe a friction clutch) coupler to preserve the transmission internals, and fluid in there to work, anyway. This is doubly true of later developments of these 3-speeds which include an overdrive 4th, like the Ford AOD or 700R4 GM transmissions.
FB Transmission in NY is probably doing the most work on EV automatics right now, with a few Ford AOD and AODE units delivered. They claim to have reduced the leakdown inside the valve body enough to maintaing shifting pressure essentially all the time. This is critical because there is no idling motor in most cases driving the primary pump that provides pressure to shift and even get started. By preventing leakdown, the FB transmission apparently doesn’t need to “pump-up” for a second like Roland Wiench’s TurboHydramatic or any such unmodified unit would. Further, the FB guys claim to have developed a “fluid clutch” which is tighter (has less slip at lower RPM) than any conventional or diesel torque converter, further reducing slip, power loss and heat build up in the transmission. Whether it all actually works hasn’t been credibly reported yet in a customer vehicle.
Keep in mind- NONE of these EV-specific modified transmissions (except maybe Roland Wiench’s, which isn’t really EV-modified) actually operates as an automatic transmission- that is, they are all set up to be fully manual and they will not go up and down through the gears automatically while in “D” without the driver moving the shift lever from one ratio to the other. Indeed, they are not automatics at all, but clutchless manuals like the VW Stickshift of old.
Since Jack is going to idle his motor, and he wants automatic operation, it doesn’t make a whole lot of sense to mess with the transmission internally to fix the leakdown or efficiency problems. He also kind of needs both the torque multiplication and the load buffering of the slip/stall characteristics inherent to the ICE-spec torque converter. He is going to have to cool the transmission, though, and will lose some power in it, to be sure. That’s a fair compromise for not twisting axles apart or having to shift gears.
Jack’s 6X (modified 4L80, which is a developed TH400) on the bench, and the stock 6L80 in the truck are true automatics. The 4L80 has the advantage of a stand-alone control box that will shift it at whatever RPM, and with some control over shift firmness, that Jack wants. He can also control the OD in each of the three primary gears, and apparently lock/unlock the torque converter at will. That’s great, but the stock 6L80 is already fully integrated into the truck, and if it can be fooled into thinking the engine is running and at operating temperature (and maybe a few other things, too…) then it can be put in either automatic or sequential manual shift mode, driven with everything that depends on it also operating normally, and Bob’s Jack’s uncle.
I’m guessing that’s the plan, anyway.
Don’t tell us you aren’t going to give that stock tranny a good college try, Jack, especially with a guy like John Spears 2-3 hours away and willing to help. It would make everything else so much easier to keep the stock 6L80…
As you well know, I’ve ALWAYS wanted to do the stock 6L80. Originally, everyone told me it could not be done, but they were a little vague as to why. I’ve purchased a TCI 4L80 modified to be a six speed, with special converter and programmer. But yes, we’re back to at least trying the 6L80 E first. I still think it will work. In fact, I’m pretty sure it will more or less work. The question at this point is will to work well, or will the shifting be obnoxious, hard, and a disappointment.
I like torque converters. THey give me a little hydraulic buffer between two quite large, quite powerful electric motors on the same shaft, and all that expensive drive train.
There will be losses. Greater than with a manual transmission. Efficiency in a 7800LB electric truck is probably a vanity in any event. If I wanted efficiency, it would not be in 7800 lb truck.
We’v eused dialectric grease and Nalox both. We no longer do. And we do not recomment their use.
I understand and accept that YOU recommend its use.
And we’re kind of out of the telephone business at this point as well.
I hope I wasn’t vague about why.
The 6L80e is fully electronic, which means it shifts and behaves via PCM command based on god-knows-what variables from the various sensors around the transmission and engine, and maybe elsewhere. The transmission itself is intimidating- its all solenoids on a common bus. You can’t even hardwire switches to them, so the PCM that comes with it is either going to have to work right as is, or its going to need to be hacked or spoofed. It might work with little effort. Probably will. Nobody really knows.
Of course, the risk in trying is that you don’t quite spoof all the variables correctly, and turn a smooth shifting automatic into a hesitant gear-banger or even non-op unit because its just confused by the missing sensor or ECM signaling. There’s no particular reason why it has to be that way, but the simple fact that in 4 years of production, no company has as yet produced a stand-alone controller for this transmission is some indication of its programming and interface complexities. Or maybe not. Anyway, I was scared of that, but there are guys out there like Spearco’s John Spears who really aren’t.
I do hope it works out to be easy.
On the efficiency side, I’ve seen estimates that it takes from 35hp to over 50hp to run a TH400/4L80e. Presumably the 6L80 is similar. That’s like 25kW to 35kW. Not trivial, but also well within the manageable “parasitic load” capacity of your motors’ output.
You’re spilling heat and electrons everywhere with this thing. You need a big siren, smoke machines and lights underneath…
I’m surprised no one has mentioned it before but your math on pairing 90ah cells to make them more even in capacity is incorrect. Unless you do go through all of the cells and pair the highest capacity cell with the lowest like you stated, you’ll only increase entropy. Everything in this world tends to go towards disorder unless you put the energy/effort into ordering it.
If the 90Ah cells are on a bell curve of 88-92Ah, pairing them together randomly would only give you a broader 176-184Ah bell curve.
Jack, could you comment why you no longer use any compounds on your connections? I’ve used NO-OX-ID Special without problems so far. I use it on the bolt threads to avoid galling between the SS bolts and aluminum terminals and to allow smooth torquing, and a very very thin coating on the contact surfaces. Have you been seeing problems?
It seems that predicting failure on OEM EVs is premature. Back when the hybrids were introduced, there was the same logic: who would buy a car thousands of dollars more to save a few bucks in gas price? did the hybrids sell very well back then? I don’t know but they’re still around today.
Jack – I’d also be interested in your further comments on dielectric and conducting greases. I tend to use one or the other on low voltage cables and connectors to keep corrosion out (thinking 5 or 10 years down the line)
Yes, I too would like to know why you don’t recommend dielectric grease. I do use it and it has worked for me but I try not to be a closed minded person. I consider you damn smart, even when it comes to electrical stuff, and value your thoughts. However, I need a good reason to change my mind. A simple statement, even from a form a damn smart person, doesn’t cut it. And, yes, I was talking 5, 10, 20 years down the road or however long the pack will last before it needs replacing, being driven in rain, snow, and left parked outside for that time period. That’s the environment the electric car I build will have to survive in.
The hybrids are still around and their sales wax and wane. Right now they are on the wane. These cars too will still be “around”. The problem is, they spent several billion on a market they predicted would bring them 150,000 units per year – actually fairly modest numbers in their world. Instead, it will bring them 10-15000. That’s a bloodbath frankly. I think they’ll still be AROUND, that hardly the definition of world changing success. And I personally think their spare components will start to appear on eBay etc and be very good for us.
In fact, I would grant that the Leaf at least appears to be a pretty good little electric car, and a number of our viewers are naturally enough among the low hanging fruit that DO purchase the car.
But they are not great enough in number for Nissan to ever get even a portion of their investment back. And that is going to cool the jets of all the paper players with press releases but no firm commitment to the market.
In a way, I see it all as a setback. In another, a pretty natural progression.
I just see it as a longer path than many. I wish we could all hold hands, sing Kumbaya, and go buy an electric car. It is just realistic.
The actual path is a bit more labored, but ultimately even more successful. We have to hope that the oil vs cars ratio allows a normal life in the interim until we can get some numbers on the road.
What do yoo mean it doesn’t cut it? It IS a simple statement. We don’t use them and we don’t recommend them. You do. So enjoy. You’re not going to change my mind by getting all snippy about it. And I don’t think I’ll change yours so I’m not going to try to.
They’re messy, and they diminish the effectiveness of the Norlocks, which we like very well. I don’t actually think they do anything. There is some efficacy in the zinc sacrificial anode. I kind of think using the Zinc coated nordlocks has at least a similar effect.
Now that I’ve given you something more than a “short answer from a smart guy” all this does is give you fuel to have a stupid argument about something we don’t think matters very much.
What we DO think matters is the bolts actually backing off from thermal cycling and vibration. We very much like the NOrdlocks as a solution, and we’re not going to cover any of that with slimy grease.
I don’t care about 20 years down the road. I care about 20 miles down the road and the car bursting into flames.
Tablets and lotions rarely offer a cure, only a treatment. My Mum for instance keeps offering to rub some lotion onto my back whenever I have stuffed my spine in again. I don’t get it either.
I buy Jacks view wholesale but on the other hand there are so many EV’s out there with cell terminals in the open air to collect damp, dust, grease and the Lord only knows what comes up off road use. Often with an “Oh look at me!” raised plastic cover to show them off with equally exposed BMS/wires clattering about. You pay good money for these cells people. I’ve said it so many times, box them up and keep everything out of the weather but like Jack does on steroids. >:-))
Jack, I don’t want to argue. I just wanted to know why you don’t like dielectric grease. I like the Nordlocks you found. They provide a very good video which convincingly demonstrates the advantages of that product. That’s the kind of information I’m looking for when it comes to maintaining electrical connections in harsh environments. I’m about as hands-on as a person can be and what I said was based on my experience. However, I like opposing opinions because they offer a chance to see things from a different perspective, like your comment on the zinc acting as a sacrificial metal and the Nordlocks not being as effective in a lubricated environment. Thanks, that was what I was looking for.
Klaus: dielectric grease doesn’t conduct electricity, so you only want to use it where metal-to-metal contact won’t otherwise occur. A good use of this grease is inside crimp or screw lugs, where the force applied by the crimp (or screw) is more than sufficient to expel the grease from the metal/metal contact areas. You don’t want to use the grease underneath a ring terminal because it is unlikely enough clamping force will be developed when the terminal is bolted down to fully expel the grease, resulting in a greatly reduced metal-to-metal contact area.
It is perfectly acceptable, however, to coat the outside of the terminals with dielectric grease once they’ve been installed to protect them from surface corrosion and incidental water. The grease does tend to attract dirt and dust, though.
Finally, some people like to put dielectric grease on the threads of bolts, particularly when joining stainless steel to aluminum (to prevent galling). There’s no harm in this as long as an appropriate lockwasher is used to ensure the clamping force is consistent and that the bolt won’t loosen from vibration over time. Belleville washers are my favorite, but internal toothed lockwashers are a close second.
Hi Jack, If you want to make notes during your tests why not use that thing sitting on the bench called a computer instead of bits of cardboard? 🙂 It makes a permanent, easy to use record of your notes and keeps it all in one place – just open a spreadsheet or text editing app and alt-tab between your volts/current display app and the note taking one. Just a thought! MW