We last spoke with Martin Klein Compact Power Inc., VP of Engineering in the summer when GM announced the battery contract with them and A123/LG Chem. Now that the first two battery packs have been delivered to GM, it seemed a good time for a follow-up interview.
What has happened over the last 6 months since being awarded the Volt contract from GM, and how did you get to the point of delivery of the first packs?
As you can imagine, its been busy. A lot of design work both within CPI and working with GM. On a program like this, where schedules are so tight, there’s not a lot of room to make assumptions, just try to make it and be corrected, so we work pretty closely with our counterpart GM to make sure every step of the way is in line with their expectations. That’s the only way to get to delivering an actual pack on time. So we did that and they were pretty pleased with that first pack as well as the second one.
Did you guys have to develop a unique cell for the packs?
Many of the elements of the cell are things that CPI and LG Chem already had. But GM had specific requirements that they needed on the pack and that did drive a few changes to the cell, it’s shape and so on. But some of the basic safety elements of the cell were things our chemists had been working on for quite some time.
CPI’s CEO P. Patil had said some changes in chemistry had to be made to meet GMs specifications, are you able to expand on that at all?
I probably can’t go too much into that but of course some previous work we had done on cells focused on hybrid-electric vehicles which is more of a power type cell very high rate of charge and discharge but not really much need for a lot of energy. Whereas this pack because of the extended range on it, energy becomes very important. So some things are made in the cell to improve the energy density.
Is the power density still important to do thinks such as rapid acceleration?
Yes it certainly is. That is one of the challenges. We did not do just a pure trade-off; X-increase in energy density equals X decrease in power. We actually maintain much of the power capability of the cell as well.
Does the actual cell assembly process take place in the manufacturing plants in Korea?
Yes, that is correct.
In your facility in Troy Michigan is that where the packs are actually being designed and built?
Yes, that is correct.
Do you bench test your packs independently of test that GM runs on it in their own lab?
Yes, there are some things we do with the pack. We try to break it down into steps, there are tests we do at the cell level, then we bring groups of cells together, we’ll call it a module, do some test there, the bring the whole pack together and do some additional tests. Some power pulses, tests on its basic voltage and current capabilities, and then of course safety. Safety is number one. We do quite a few safety check on it. Then we would deliver it to GM.
Are the testing procedures standardized, are they public information?
There are some basic standardized test that are done. The USABC for example, they have some tests, USCAR, they have some tests that they’ve developed generally for hybrid packs. That would be one series of test we do.
But of course this is a whole new venture, again as far as the power and energy density requirements. I’m sure GM has done some studies on customer usage patterns and so they would want to take a look at that themselves.
What kind of temperature ranges are the packs tested at?
I cant go into too much detail as that would kind of be a GM requirement. It’s a fairly aggressive range of temperatures. GM intends to make this vehicle useful to nearly all customers. ..The last thing we would want to see is a customer in a climate which would be expected of a vehicle and not operate right.
How do you estimate the life expectancy of the battery pack?
We have quite a bit of data that we can use to extrapolate. Work that we’ve done with USABC thats a very similar chemistry. We can plot curves, do curve-fitting on the data that we have. We have several years of data now. We’ve started several generation of cells on test cycles and they all seem to follow a certain curve. So using that curve we can project the life, we fell, pretty accurately. One of the things we constantly do a bit recursively, is we estimate what the curve should be, and then 6 months later we’ll go back and test our hypothesis.
You guys use a manganese spinel structure for you cathode?
It’s a mixed cathode, some elements of spinel and some elements of a mix, not pure spinel.
Now that you’ve delivered two packs, are you going to continue to deliver packs up to the point GM decides on which company to go with (CPI/LG versus A123/Conti) for the production car?
We’re not stopping. We’re working on the next group of packs right now.
Do you respond to GM’s feedback with each new pack?
Absolutely, each new pack is an evolution of the previous one. We take the lessons learned from the first pack and put those into the second pack the best we can. The second pack for example has improvements in its assemblability. It’s we feel more robust than the first pack. As we were designing the first pack we said, well this works, and this works as well, and then when it came time to assemble certain things we said well yeah it works, but this would work better. We have meetings with GM, they come and review progress and they say that’s fine but on the next pack we may want to tweak this.
So we’ve done some things with they way that we mount the cabling, the way we mount some of the modules.
Is the weight of the current packs finalized for what it will be in the production car, or might that change as well?
Well you can imagine, anything that can be done to reduce the weight but still maintain all the functionality and safety is very important. The first several packs that we’re delivering, they’re not necessarily optimized for weight because what GM really needs to do is test the performance ad functionality of the pack. Are they getting the energy they expected, are they getting the power they’re expecting, is current hitting the maximum they expect, is some of the software working the way they expect. Those things are really important to get started.
In parallel we can have some of the designers go out and work in parallel improvements to try and shave weight off it.
This entry was posted on Wednesday, January 2nd, 2008 at 6:32 am and is filed under Battery, Engineering, Original GM-Volt Interviews. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.
Jan 2nd, 2008 (8:31 am)Lyle – thanks for another excellent interview. Lots of good info here.
The levels in this picture are also a little off, here’s a better one:
http://mysite.verizon.net/vzenu6hr/ebay_pictures/cpi_pack1.jpg
In Photoshop, just press Control-Shift-L (all 3 keys together) to do Auto-Levels adjust. Hope this helps.
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Jan 2nd, 2008 (9:00 am)He sure does not sound pessimistic like that other guy’s brother in law!!!!
The time is right. This is going to work!!!
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Jan 2nd, 2008 (9:55 am)Keep up the good work with the batteries. Efficiency of batteries way surpasses hydrogen. Even green dreams of PV to H2 to fuel cell to motivation a la Honda are grossly inefficient compared to PV to grid to battery. Plus, no new infrastructure required. I AM VERY CONCERNED ABOUT POOR GM PERFORMANCE AS IN FEW 5 STAR CRASH GM VEHICLES AND ALSO VISIBILITY IN THE VOLT AS SHOWN LOOKS MISERABLE INCLUDING THE SMALL MIRRORS. WE ARE NOT LITTLE KIDS LOOKING TO DRIVE A “TRANSFORMER” OVERRULE YOUR STYLISTS AND IMPROVE VISIBILITY AND PASSENGER PROTECTION.
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Jan 2nd, 2008 (10:09 am)Great interview Lyle, glad to hear about the upcoming changes in the site. I hope you have some sort of forum there for lobying/marketing/promoting YOUR site rather than say GM’s product. I think it sells better if you catch my drift.
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Jan 2nd, 2008 (10:30 am)[quote comment="23832"]I AM VERY CONCERNED ABOUT POOR GM PERFORMANCE AS IN FEW 5 STAR CRASH GM VEHICLES AND ALSO VISIBILITY IN THE VOLT AS SHOWN LOOKS MISERABLE INCLUDING THE SMALL MIRRORS. WE ARE NOT LITTLE KIDS LOOKING TO DRIVE A “TRANSFORMER” OVERRULE YOUR STYLISTS AND IMPROVE VISIBILITY AND PASSENGER PROTECTION.[/quote]
Dear Richard #3,
Just for your info, here in Belgium, my family ownes two Opel(GM) cars, an Opel Corsa (city car) and an Opel Astra break (station-wagon), the first got four marks and the Astra five marks (the maximum) for the Euro-Ncap test, that means in each category of vehicle the best performance in security both active and passive at the time of their introduction.
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Jan 2nd, 2008 (11:36 am)I’ll add my 2¢ to Richard Poor, #3.
Not all GM cars win praise for reliability.
The Pontiac Solstice comes to mind for some reason.
The Volt is brand new and needs to be extremely reliable, very user friendly, and aesthetically pleasing, so that the masses are attracted to it enough to buy it by the boat load. Remember the 60% of new car buyers that won’t buy American. That is a huge market to ignore.
#5 Jean-Charles Jacquemin, Can you please tell me how you changed your text to italics? Are you using the font tag in HTML? Thank you.
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Jan 2nd, 2008 (11:53 am)In response to #3:
Don’t worry too much about visibility, the production version Volt most likely will be quite different from the concept. You can see some teaser pics of the early production design on this site.
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Jan 2nd, 2008 (12:00 pm)Noel Park, have you seen the wait list number yet? 8101 right now!
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Jan 2nd, 2008 (12:06 pm)To Rachiid Amul #6,
Dear Rachiid, I did’nt do anything, I just “quoted” Richard poor #3 (Cliking Quote after the date and and time of the post and editing the quote, I think Lyle wrote a macro, did you Lyle ?).
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Jan 2nd, 2008 (12:12 pm)Rashiid, #8:
Alll Riiight!
I got the e-mail alert from Lyle this AM, and he is talking about 10,000. Do you think he has a few extras up his sleeve?
He also mentioned his committment to trying to prevent “price gouging”. A big order if you ask me, but God bless him if he (we) can do it.
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Jan 2nd, 2008 (12:28 pm)Lyle:
You forgot one important question to ask
Whats the cycle life and calendar life ?
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Jan 2nd, 2008 (12:29 pm)If the first Volt works out, we are thinking to getting a second one for my work, to replace my faithful S-10. I really need a pickup, but what can you do?
Once I suggested sticking a wooden bed out of the hatch a la “The Grapes of Wrath”. Come to think about it, maybe that would be a good way to embarrass GM into developing a pickup version! Maybe a ’50s style little folding one wheel trailer?
Anyway, if we are in the market for 2 Volts, does that mean we can put our name on the waiting list twice? Not to pad the numbers you understand, but every little bit may help.
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Jan 2nd, 2008 (12:51 pm)Noel @ 12, my family has 2 names submitted on the list, because two are feasible and likely, assuming GM can deliver. I’d suggest adding the other name.
On another note [may be bad or may be good depending on how you view the price of oil], it’s hit $100 a barrel, a new record. GM, Please get cracking!
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Jan 2nd, 2008 (12:54 pm)“It’s a mixed cathode, some elements of spinel and some elements of a mix, not pure spinel.”
Makes sense why they can adjust the energy and power values, since to my knowledge the spinel nanostructure of manganese oxides improves conductivity and power, but decreases energy storage.
So it sounds like they are putting in different amounts of spinel to balance power with energy.
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Jan 2nd, 2008 (1:32 pm)On most other sites, including news articles, I keep reading that the Volt is waiting for its battery to be invented, and may not come out for that reason. And that’s why the production date is 3 years out.
But what I conclude from this and the other interviews from officials at A123 / Conti (thanks Lyle), they are meeting GM’s basic specs of safety, power, energy, longevity, (and price?) now. And, at this point, it’s more a matter of tweaking, and optimizing the pack.
In other words, both battery companies are pretty darn close, but are meeting the basic requirements. Am I wrong?
Volts #1 fan
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Jan 2nd, 2008 (1:39 pm)Richard #4: But many of us REALLY like the looks of the concept vehicle…………
Unfortunatly, banjoez #7 is correct. The production car will be quite a bit different.
noel park #10: I was wondering how Lyle was going to get GM to prevent the price gouging as well. Maybe if we pull into the dealership with a magnetic Volt bumper sticker, it will be like the secret handshake!!! As far as the wait list counter, with the way it has been rising lately, it will be at 10K pretty quickly. And I agree with Dave B #13: Tow cars – two votes….
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Jan 2nd, 2008 (1:40 pm)Of interest was the work they’ve already done in cycle testing and estimating lifespan, etc. From what he said, there doesn’t seem to be anything yet that’s
been a surprise to these battery folks. I’d say they probably had pre-estimated very accurately all the requirements before they delivered the first pack. And that, assuredly, included thermal properties of their cells, modules and pack. From all this, I would need to hear a ton of detailed evidence that either of these battery technologies have significant thermal issues. In fact, we’ve heard zero details of supposed thermal problems, from anybody. That’s zero, as in zero.
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Jan 2nd, 2008 (1:41 pm)Sorry for my typo as well. I meant Two, not Tow.
And I am sure it was not a Freudian slip.
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Jan 2nd, 2008 (3:00 pm)Having been able to test drive a EV-1 a few years back, I for one am ready to cut loose the gas line and plug in for power! I hope that GM produces this car and in greater numbers than the EV-1. The volt will make my garage look modern!
There was a reason that the EV-1 drivers went to great lengths to keep their cars, they were well made and performed great.
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Jan 2nd, 2008 (3:06 pm)Having worked some years in the auto design area, I have a comment on the appearance vs. design topic, i.e.:
Richard #4: But many of us REALLY like the looks of the concept vehicle…………
Unfortunatly, banjoez #7 is correct. The production car will be quite a bit different.
Many of you probably read the recent posting about the design changes needed to reduce drag and how drag turned out to be the largest drain in range. So it was a required trade-off. Those “sharp edge” designs that have been popular in recent years are also energy hogs due to drag. Unfortunate, since I also loved the origina design, but remember that’s only a concept. You see them a lot in the shows but rarely in the show rooms (except the near-production concepts, which are usually not so exotic).
It’s similar for the large (safe) mirrors vs. drag, since those big “ears” are a huge drag, but, of course, you need to good visibility, so there will be some trades there as well.
BTW, there are regulations and tests that are done during auto design for side mirror visibility, and a 1000 other things, that any final design will need to pass. They always trump design since you can’t sell it if don’t pass the regs, no matter how good it looks.
Anyway, like the rest of you, I hope GM pull this off in a timely and acceptable way. They have the resources to do it, if the will is there (sounds like it is for now).
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Jan 2nd, 2008 (3:24 pm)I’m excited to see the good progress being made toward the eventual introduction of the Volt! Oil just hit $100 / barrel. I want one now.
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Jan 2nd, 2008 (3:49 pm)I am with you noel park #12, I need to replace my pickup before my car. There are a lot of commuters that drive pickups now. So let’s hope GM brings their small pickup out within a year of the Volt.
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Jan 2nd, 2008 (4:16 pm)You asked “How do you estimate the life expectancy of the battery pack?” instead of “WHAT is the life expectancy”!
I also would have liked to have seen a question regarding what the “stumbling blocks” are to meeting GM’s requirements, if there are any, and how quickly it could be mass produced. This would be another way of asking “Why is GM putting off the production date so far into the future due to battery issues?”
Maybe GM is just trying to throw off the competition. Everyone is pretty much expecting another company to beat GM to the finish line (or should I say the “starting line”?) well maybe they don’t want the competition to know they will be in production sooner rather than later?
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Jan 2nd, 2008 (4:30 pm)I was reading an article in my resident newspaper (the Birmingham News…yes, Alabama) that was on the achievements of one Robert (Bob) Lutz. Of all the things he has done in his career, his proudest achievement was fostering a change at GM in which the DESIGNERS, not the accountants built the car. Many are fearful that upon his retirement, all of this renewed Harley Earl vitality will slip away and projects like the Volt will never be done again, as the bean counters would gain control of GM’s congress. I think that in many respects, we have as a country lost faith in the abilities of our own people. I believe that there would be absolutely no point whatsoever for designers to not try to keep the Volt looking as forward thinking as possible while still adhering to the laws of physics, which sadly to say are not yet breakable. But there are a myriad of ways that they can still keep favorable design cues in the Volt while making it as slippery as possible. The Prius is aerodynamic, true, but I believe that with designers finally loosed from the corporate constriction called an accounting department, it will be possible to construct a vehicle that is efficient yet easily and attractibly identifiable as a Volt. Give it time.
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Jan 2nd, 2008 (4:51 pm)Pat, #20:
Roger that on the mirrors. Just roll down the window and stick your cupped hand out at 80 mph. You’ll be lucky if you don’t sprain your shoulder. They need to put a Wink mirror or a backup camera in the Volt, and do away with the side mirrors.
You don’t see any side mirrors on Nextel cup cars, for example. We finally took them off of our Corvettes. If you want to pass, pull up even in the braking zone where I can see you, or take the risk of getting chopped!
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Jan 2nd, 2008 (5:24 pm)Maybe a Volt SS with 30 mile range with concept style . That would work for me. I could probly still get to work two days on a charge. And maybe by late 2009 batterys will be able to get 50 or 60 miles to a charge. It is hard to tell alot of late model cars apart. I like the looks of the concept. IT is sharp.
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Jan 2nd, 2008 (5:28 pm)Another subtle aero improvement besides side mirrors is the wipers. If you could have them completely recessed under the hood instead of up against the windshield (where almost all of the airflow from the whole front of the car travels) it would probably improve drag immensely.
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Jan 2nd, 2008 (6:00 pm)EXCELLENT POST!! Thanks for the great interview Lyle. I especially appreciated the questions on the cell chemistry.
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Jan 2nd, 2008 (6:12 pm)[quote comment="23867"]To Rachiid Amul #6,
Dear Rachiid, I did’nt do anything, I just “quoted” Richard poor #3 (Cliking Quote after the date and and time of the post and editing the quote, I think Lyle wrote a macro, did you Lyle ?).[/quote]
Thank you Jean-Charles. I never noticed the quote link before.
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Jan 2nd, 2008 (6:37 pm)[quote comment="23924"]
I also would have liked to have seen a question regarding what the “stumbling blocks” are to meeting GM’s requirements, if there are any, and how quickly it could be mass produced. This would be another way of asking “Why is GM putting off the production date so far into the future due to battery issues?”
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One way to put the 2010 production date into perspective – a normal car whose technology is already well-established already probably takes 3-5 years to develop and get into mass production. In that light, 2010 isn’t far in the future, it’s an aggressive target.
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Jan 2nd, 2008 (6:53 pm)Car manufacturers often make changes to the body style and interior every year. This makes the new model noticably different, which helps create demand. With this as a gauge, I’m not surprised that some people wonder why the Volt is taking so long.
The reality is quite different. Changes from one model year to the next are usually cosmetic and/or minor. A completely new car design takes 3-5 years to produce. Since this is usually done while other similar cars are being sold, most people never notice.
Even without the batteries, the Volt schedule is aggressive. I’m sure they can do it if they put their minds to it, but it won’t be business as usual for the developers.
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Jan 2nd, 2008 (7:33 pm)I’m the only person I know who’s been praying for gas to top 6$ a gallon nation wide… this is a start and if it keeps going maybe we’ll finally spur some new innovation from the big names in autos.
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Jan 3rd, 2008 (12:07 am)A few questions: why are we talking trying to get 60 miles per charge out of the batteries. Almost 20 years ago I drove the GM EV1 and got 110 miles on a full charge (and the Tesla is returning 220 miles on a charge).See http://www.teslamotors.com/
What type of batteries are being used? I would hope Lithium Ion as they are far more compact and powerful than nickle metal hydride.
Finally this concept vehicle looks like it has a coefficient of drag of about .40, that would hardly promote fuel economy. Why not use a design like a Toyota Prius with a coefficient of drag of .26.
These are not criticisms they are questions; I am all for the plug in (PHEV)approach,
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Jan 3rd, 2008 (9:13 am)I also think its a bit strange that they are talking about 60 miles on a charge when the competition is talking about >100 but presumably the 60 number is to save money and/or make the car lighter? The 60 number meets the needs of something like 90% of regular daily drivers (search for the detailed postings on this subject). And of course you have the gas generator as backup, which makes your range indefinite (some of the competitors don’t have gas backup generator which is a major negative).
I’m one of the exceptions, I drive 80 miles per day. I don’t like commuting 40 miles each way to work but stuff happens, I don’t want to move my family every time I get a new job. For me having to use gasoline daily with an electric car would be a major negative with this particular model and I’d probably be more apt to go with the competition all else being equal. However obviously cost of the car and other features would be important deciding factors. And again I’m in the minority of drivers here, so GM might be doing the right thing in putting their focus where they have.
Also I’m assuming I will NOT be able to charge the car while I’m at work (probably a safe assumption for at least the next 10 years). If I could charge at work, then this model would be fine (for all electric use).
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Jan 3rd, 2008 (10:53 am)Good interview and whole site is very informative
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Jan 3rd, 2008 (11:35 am)AES, #27:
Right. You have to take every little bit, anywhere you can find it, to arrive at the optimum whole.
I am not a huge fan of stock car racing, but it is amazing how hard those guys work in the wind tunnel to achieve very subtle changes that most of us (including, they hope, the tech inspectors!) can’t even see.
Even a 1% gain is huge when the whole field qualifies within one second of the pole. So it is with fuel economy. When you are looking at tens of thousands of cars, 1% is massive.
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Jan 3rd, 2008 (11:46 am)[quote comment="24025"]A few questions: why are we talking trying to get 60 miles per charge out of the batteries. Almost 20 years ago I drove the GM EV1 and got 110 miles on a full charge (and the Tesla is returning 220 miles on a charge).See http://www.teslamotors.com/
What type of batteries are being used? I would hope Lithium Ion as they are far more compact and powerful than nickle metal hydride.
Finally this concept vehicle looks like it has a coefficient of drag of about .40, that would hardly promote fuel economy. Why not use a design like a Toyota Prius with a coefficient of drag of .26.
These are not criticisms they are questions; I am all for the plug in (PHEV)approach,[/quote]
Hello and welcome to the site,
Volt uses lithium ion batteries obviously, but it’s using fewer of them than either of the past examples you mentioned, both to control weight and cost, and also so that the car can seat 4-5 people people and have room for a trunk, yet still handle most daily driving without any gas. It’s a practical compromise.
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Jan 3rd, 2008 (12:29 pm)Like Gordo, I live 40 miles away from where I work. With my Saturn getting 22 mpg, I visit the Hess station twice a week. If I could cut that down to once a month, I’d be a happy man!
As far as what it will look like, yes, the government controls how fast the wipers run, how loud the horn is, etc, but I read where the Chevy SSR went from concept to production in 6 months and retained most of its original style.
I think GM is on target with this style of Hybrid technology instead of the traditional gas engine/ electric motor powertrain and I hope that consumers are intelligent enough to appreciate it when the vehicle is finally produced.
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Jan 3rd, 2008 (12:40 pm)I hope they don’t lose all the ‘edgy’ looks of the car. That’s what first made me say ‘Hey, what it that! I want one.” In the new ‘fuzzy’ picture that was posted the first thing that sprang to mind was it looked like the front of the Malibu, a car I CAN ignore, thank you very much…
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Jan 3rd, 2008 (12:55 pm)What are the options for electric only? Would I be able to replace the generator with more batteries?
I currently drive a Ranger EV, and I get about 30 miles in cold, dark weather (lights & heater eat up some mileage) and approx. 45 miles in summer. I would like to see an option of all electric, if it had 100-120 miles range. With Lithium batteries in the Ranger I could easily get that.
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Jan 3rd, 2008 (1:22 pm)I’m sure there will be plenty of people that rip out the gas generator and stick some extra batteries in there instead, but I doubt that will be a factory option. Most people really want that backup generator – for one thing, you can’t go on any long trips without it. For another, eventually those batteries aren’t going to hold their charge anymore, and without the backup generator, you will get stranded on the road. Maybe you don’t think that’s a big deal, but most people would.
On the other hand, the car itself should give you plenty of advanced warning when its time to replace your batteries. And most people will have an alternate vehicle to drive on long trips. So maybe the all electric should be a factory option?
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Jan 3rd, 2008 (7:55 pm)Less weight,less battery’s, but add to all shocks coil and magnets to generate electrict,as car goes down the road,bumps move magnet’s up and down past coils to creat electric charge to fewer batteries
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Jan 5th, 2008 (5:54 pm)YES.. a electric only option should be available. I only have 10 miles each way to work .. and most of the people in the Pittsburgh area drive less than 15 miles each way. 40 miles in winter would be just fine for me. This should be the low price option. 40 miles all electric. $25K or less…
… you couldn’t make enough of them!!
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Jan 5th, 2008 (6:33 pm)A gas generator is probably only a $300 part so don’t look for big savings there…
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Jan 5th, 2008 (10:19 pm)How about no volts,but use G-force generated inverted force suportet by G-pounds,at 3600 rpm developing 900 G-s on liquid volume weight being used equiling multiplyed inverted force as direct driving torque.With no limit of increased speed.
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Jan 11th, 2008 (11:02 pm)Balance the wheels off a little bit to keep the chocks moving just a little would add constent bumping but not to much but enough to generate a steedy volt supply to fewer batteries giving you unlimeded travel distance.
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Jan 11th, 2008 (11:09 pm)I like the way the car looks,could add air turbine port intreance to the front of the car that is hiting the wind any way to turn generator to add volts.
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Jan 23rd, 2008 (7:15 pm)A chock and with a coil and a magnet to move up and down inside the coil as the chock takes bumps in the road is symple to understand,producing volts with the slitest of movement up or coming down,a real no brainer.So wy not make it so.Happy traviling…
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Jan 23rd, 2008 (7:25 pm)By using many of these coils,you could get a hundred or thousand times that of one coil,I change the the Name from Volt to Volt Volt 2
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