Why Not Improve The Cheap Chemistry?



When General Motors launched its pioneering two-seat EV1 in 1997, its batteries were "advanced" lead acid (PbA). That means they were big, heavy, had low energy density and a limited life. But it was the best available chemistry at the time. That first EV1's T-shaped pack of 27 PbA modules weighed nearly 1200 pounds and stored the energy equivalent of a half-gallon of gas. The fact that you could coax 50-70 miles of (warm-weather, flat-road) range out of that tiny amount of on-board energy was a testament to the extreme efficiency of that car.

Then, by working hard with Nickel Metal Hydride (NiMH) developer Ovonic Battery Co., GM was able to offer an optional NiMH pack for the '99 EV1. Roughly the same size and weight as the PbA pack, it required the addition of a cooling system and was much more expensive, but it approximately doubled on-board energy. So, 1999 model year NiMH EV1 drivers could leave home with the equivalent of an entire gallon of gas in their "tank" and drive 100-plus miles.

But lithium-polymer, the next generation battery technology that was supposed to make BEVs much more affordable and practical, never came close to matching expectations. And it wasn't long before PbA's low energy and NiMH's much higher cost put an end to California's ridiculous EV sales mandate – and all the major automakers' production pure EV programs – for a while.

envia gm cartoon graphic


Today's renewed hope for volume EV sales is thanks largely to the emergence of lithium-ion battery chemistry, which roughly doubles the energy density of NiMH and quadruples PbA. But li-ion costs even more than NiMH, so the growing list of EVs and hybrids that use it are still way more expensive than conventional ICE counterparts.

The search is on for hidden potential in good old PbA (lead-acid) batteries.

But Troy, MI start-up Energy Power Systems (EPS) founder/CEO Subhash Dhar – who has toiled in the EV battery business for more than 30 years – contends that PbA deserves another chance. Along with inventor Stan Ovshinsky, he founded Ovonic in 1981. Then he was involved in li-ion development as vice chairman of EnerDel and president of Ener1. He then served as chairman and CEO of Envia Systems, a developer of advanced battery anode and cathode materials (and which GM has an interest in). And now he's searching for hidden potential in good old PbA.

"We have been working on developing very advanced battery systems based on lead-acid chemistry," he says. "When I concluded my assignment with Envia two years ago, I realized that we in the battery industry had been making a lot of promises, going back to 1991, to achieve the performance and cost targets that would enable the transportation industry to switch over to electrified powertrains. The focus has been how far you can go on a charge, so the bulk of the effort has been to maximize energy density while keeping an eye on cost.

"We in the battery industry had been making a lot of promises, going back to 1991."

"We made that promise in the early '90s and repeated it in the early 2000's, and the industry has made significant advances in energy density, battery life and performance. But the issue still remains the cost. We are still at $600-$700 per kilowatt hour, depending on the chemistry, the system and the vehicle, against a target set back in 1991-92 of $150. So for a pure electric vehicle with a 30-kWh battery pack, we're talking $20-plus thousand just in the battery, which is not an economically viable proposition from the consumer standpoint."

Dhar concluded that as long as EV batteries required expensive materials – nickel, cobalt, copper and rare-earth metals in NiMH, expensive electrolyte used in li-ion – the hope that their cost would come down with volume and time was unrealistic. So why not try something different? Instead of chasing the highest-performance chemistry, then trying to figure out a way to reduce the cost, what if they would start with the lowest-cost chemistry and try improving its performance?

So he set out to optimize PbA chemistry and battery design in hopes of achieving the power (not necessarily energy) density of NiMH. "If we can do that without disturbing the fundamental cost structure of the chemistry, that is potentially a winner, maybe the solution.

EV1 at EVS26

He put together a team of people with experience in NiMH and li-ion batteries and materials science to work on microstructure technology and battery composition, to start thinking "out of the box" and taking a completely different approach to developing a product using PbA chemistry by working on the cathode and anode materials, the substrate, the grid and how the batteries would be designed and assembled. He thought 45-50 Wh/kg might be possible, but not the 150 currently demonstrated by li-ion.

And NiMH is still expensive. "In the late '90s, early 2000s, the Prius battery was $2,500-2,800 per vehicle," he says, "and my guess is that it's still $1,700-$1,800, even though it's a small battery. My belief is that if NiMH batteries were magically cut in cost by a factor of three, we would see a significant surge in the growth of hybrid electric vehicles. With micro hybrids, mild hybrids, even full hybrids, you don't need a battery that's more than 1.2-1.5 kWh, provided you can achieve enough power to add torque to your powertrain at an acceptable cost."

"I believe we can combine our high-power, low-cost battery with a lower-cost, higher-energy li-ion battery to make a hybrid pack that could reduce the overall cost by a factor of two."

So his focus has been on improving power density. "We have taken the power of lead-acid chemistry from the typical 200-300 watts per kilogram to 2000, and we have seen cycle-life improvements in our prototypes by factors of three to four. We have accomplished that by taking out all the dead weight, increasing the utilization of active materials and redesigning the pack for reduced internal resistance, so its reactions are faster. The rate at which you put electrons in and draw electrons out of this pack are five to six times faster than today's best power-density PbA battery." His vision is to offer a power-to-energy ratio of 30 to 35 at lead-acid chemistry cost. "Some companies have done that with li-ion, but at four times that cost."

Dhar thinks advanced PbA might also have potential in plug-ins and big-battery EVs. "We are developing solutions for micro, mild and full hybrids, but we also have approaches for applying this product to PHEVs, EREVs and pure EVs. I believe we can combine our high-power, low-cost battery with a lower-cost, higher-energy li-ion battery to make a hybrid pack that could reduce the overall cost by a factor of two. I think it's possible to make a high-energy li-ion battery for maybe $400 per kWh or less, and if I take, say, 10 kWh of high-energy Li-ion battery and attach it to 2-1/2 or three kWh of EPS high-power battery, I can shift the power load to the EPS battery and use energy from the li-ion battery for cruising. The combined cost of this system should be 40-50 percent less than a li-ion pack optimized for both high power and high energy."

ev1 promo pictureDhar has kept this effort low-profile because he did not want to be another over-optimistic battery developer going public with bold statements and promises he ultimately can't keep. He has seen that happen way too often. "I understand why people sometimes have to do that," he says, "to raise capital. In our case, we are fortunate that raising capital is not our issue today, or likely to be tomorrow." That is because, he says, EPS has more than sufficient backing from his partner Dennis Townsend, founder and chairman of Baltimore-based Townsend Capital.

When we talked, he had put off approaching automakers because he wanted to be further down the development road before he did. "I don't want a large gap between talking to them and when I can say, "Here is a prototype, go test it." But you may see Subhash Dhar and EPS telling their advanced PbA story at the Advanced Automotive Batteries Conference (AABC) next February and at a trade show or two in 2013.

Editor's Note: A timely coincidence showed up in our inbox as we were getting this post ready. A new report from Pike Research on "Advanced Lead-Acid Batteries." We're not going to spend the nearly $4,000 it costs to read, but this shows Dhar isn't the only one taking another look at lead-acid batteries.


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    • 1 Second Ago
  • 56 Comments
      Joeviocoe
      • 2 Years Ago
      The EV-1 wasn't outright killed by one thing. It was more Euthanized because it was sick and had so many ailments. Yes, the demand was low and the costs were high. But GM could have done more to help with that. Instead, they saw it as 'no worth the effort'. And since they were being forced, they killed it MUCH faster than it would have died on its own. Like a baby born with a disease, an illness that doctors have been working on curing, and making slow but sure progress. But costs and burdens of caring for a sick child were too much to bear... so GM threw it in the dumpster and blamed the illness. Can't really blame them. It's a car technology, not a human being. And they are a company, not a parent. They did what was most profitable at the time. Yes the world need cars like these, but there will be more false starts than successes. Tragic yes, but lessons learned, lets keep trying.
      • 2 Years Ago
      If you put a Tesla 85kWh pack into an EV1 ( it weighs about the same as the EV1 pack ) you would have an EV1 that could drive 518 miles at 60mph. If you slowed down to 45mph, it would have a range of 739 miles. Too bad GM crushed them all to prevent people from improving them as battery technology improved.
      Andrew Richard Rose
      • 2 Years Ago
      Witless , as usual ! You can buy consumer Li-ion here in Italy on the high street for $400 a Kw/h
        • 2 Years Ago
        @Andrew Richard Rose
        Consumer electronics batteries don't come with thermal management systems or fault tolerant charge balancing systems. Add another $500/kWh of thermal management systems and $120/kWh of intrusion prevention and you will be able to build an EV battery storage system for $1020/kWh. - OH wait that's what Tesla does
      2 wheeled menace
      • 2 Years Ago
      Spec: crash standards. It would fail side impact, and roof rollover tests. It would have to be wider and taller to compensate. Front and rear? doubtful as well. Modern front/rear/side tests are intended to hit the car with something like the front of a SUV. It would also need side airbags which would make the sides even wider still. A perfect example of what our modern safety standards have done to cars in the past 15 years, is to compare something like a modern Nissan Sentra to a 1994 Nissan Sentra. Do the same thing with all econoboxes designed in the 1990's. You'll see every car pack on ~500lbs, get wider, taller, and require a very high tech engine in order to achieve the same fuel economy it once did. Unlike in an internal combustion propelled vehicle though, you can't make an electric motor more efficient to compensate. So as safety standards continue to tighten up, electrics will have a problem.
      Actionable Mango
      • 2 Years Ago
      I would think the EV-1 would be illegal and unmarketable today. I see two primary reasons: 1) Additional regulation for safety standards and safety equipment, which leads to increased weight. 2) Customers expect more performance, features, and space, which leads to increased size and weight. If by "design" you only meant shape, then I suppose it could keep the same shape, yes.
      • 2 Years Ago
      This is disturbing. I had high hopes for Envia Systems, and now I see its chairman and CEO has stepped down after he "concluded" his "assignment" there. Huh? It would not have surprised me to learn Envia's lofty claims could not be met, but we're seeing it through the back door when Dhar states that we're "still at $600-$700 per kilowatt hour." Envia claimed they could realize $125/kWh and now I see their website won't even load. So what happened to Envia and its claims? That's the story I want to read about.
        2 wheeled menace
        • 2 Years Ago
        I want to read about what happened with those claims as well. Too much snake oil in the battery industry. We need less of it. Overpromising and underdelivering is never good.
        Spec
        • 2 Years Ago
        Well maybe he got tossed a coupled years back and Envia has better management now? Who knows? But a large amount of skepticism is required with the battery biz.
      Aaron
      • 2 Years Ago
      "...the system and the vehicle, against a target set back in 1991-92 of $150. So for a pure electric vehicle with a 30-kWh battery pack, we're talking $20-plus thousand just in the battery..." A 30kWh battery pack in the 90s, with PbA technology, would have been incredibly expensive AND heavy. We changed battery chemistry so the comparison doesn't work. We have much lighter, more energy-dense batteries today than what was available then. If we kept to PbA technology, maybe we would be down to $150, but we would still have a very large, heavy battery pack.
        Spec
        • 2 Years Ago
        @Aaron
        Yeah . . . it seems like a dead-end to me. Even if you reduce the price, the lead-acid batteries don't tend to last as long and they are just too damn heavy. People complain as is with limited range the lead-acid batteries would make that worse. Switching the anode appears to make them last longer but that doesn't fix the weight issue. I think lead still has some uses in start-stop vehicles and NEVs where the battery does not need to be so big.
      Joeviocoe
      • 2 Years Ago
      Expectations from both sides will converge into an agreeable compromise. Automakers may think that EVs must be a "gasoline equivalent vehicle"... right now. But as more and more people plug in, and have access to fast chargers and/or range extenders to handle longer trips... the consumer expectations will change, to reflect less of a need to carry around a weeks worth of energy (as is the paradigm with gasoline cars). Automakers will then shift their focus to more reasonable expectations of battery costs and density.
      Ford Future
      • 2 Years Ago
      Why is the discredited Witz even writing articles for AutoBlogGreen?
      Electron
      • 2 Years Ago
      I doesn't really matter. The EV-1 is dead with very few survivors left of the great 2002 EV-1 massacre. It was a rather messy affair that the General doesn't want to be reminded of any more. It's sort of embarrassing even for a company that considers the Spark an acceptable car design.
      • 2 Years Ago
      Dhar has kept this effort low-profile because he did not want to be another over-optimistic battery developer going public with bold statements and promises he ultimately can't keep. He has seen that happen way too often. "I understand why people sometimes have to do that," he says, "to raise capital..." Even first-hand, apparently. Bummer.
        Spec
        • 2 Years Ago
        Ah . . . you think new Envia management made overly broad claims to raise money? That would not surprise me in the least. That would seem standard operating procedure these days. :-/
      lad
      • 2 Years Ago
      No Gary; Oil Politics killed the ZEV program in California under the direction of then Governor Pete Wilson; it is interesting his wife worked for Chevron and also, that Chevron controlled the Ovonics patent....but,that's another story. Poor battery research advancement was not the reason.
        Spec
        • 2 Years Ago
        @lad
        Oil politics did kill the ZEV program but the batteries available at the time were expensive and/or crappy. EV proponents need to let that go . . . EVs still struggle with good Li-Ion batteries versus $4/gallon gas. They were hopeless with Lead-Acid and NiMH batteries versus $1.90/gallon gas. Just let it go.
          lad
          • 2 Years Ago
          @Spec
          I have let go of it; just wanted the record to be correct. BTW, the only lab work I see on the horizon with a chance of developing a decent battery chemistry is the recently announced 555 project, funded by DOE and managed by Argonne Labs. But, I have doubts the costs for producing any batteries as a result of the research will be low-cost or will even make it to market because the research results will be patented and under control of patent holders. The DOE should make the results of this research open to all who want to create the manufacturing processes and market the batteries. This would improve the possibility of the lab work being used to produce a product and less chance of the knowledge being locked up in a company safe somewhere. At one time Government funded research was published in the Public Domain and anyone could build products using the results; however, now it is all patented and subject to Industrial and political control.
          JakeY
          • 2 Years Ago
          @Spec
          I think nimh would have had a decent chance (looking at RAV4-EVs still running). But I don't see us going back to those chemistries for EVs given the way prices are dropping for li-ion.
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