Using a souped-up version of a chemistry that's been around since the days of Edison, a Detroit-area startup wants to slash the costs of batteries for hybrids and plug-in cars.
Energy Power Systems (EPS) says it has boosted the power density and cycle life of the venerable lead-acid battery, without touching the low costs that made it desirable in the first place. With the new technology, batteries for mild hybrids and plug-in cars could cost less than half of what they do today, the company says.
Subhash Dhar, chairman, CEO, and founder of EPS, said in an interview:
The concept has always been to start with a chemistry that gives you high energy density, and then hope you can reduce the cost. But the industry has never made much progress in terms of cost. So we turned it upside down -- we started with low cost and improved the technology, so we can get the performance without disturbing the cost structure.
Energy Power Systems (EPS) proposes replacement of a 16-kWh lithium-ion battery, like the one in the Chevy Volt, with a 9-kWh lithium pack and a high-power, 3.5-kWh lead-acid pack. (Source: EPS)
In truth, the energy numbers of EPS' batteries are puny compared to that of today's lithium-ion batteries. Whereas, lithium-ion typically checks in around 150 Wh/kg, the EPS battery is 40 Wh/kg. But that doesn't worry Dhar. The EPS battery is not targeted at high energy (which translates to driving range in an EV), but is instead focused on power density. Power density is far more important for full hybrids, mild hybrids, and micro-hybrids, since those vehicles can extend their range by burning gasoline, Dhar told us. "When you realize that energy isn't critical, and power is critical, you can boost the power and not worry about disturbing the fundamental low-cost structure of lead-acid," he said.
That's why his company has lifted the power density of lead-acid from about 200 W/kg to 1,600 W/kg. Cycle life has similarly been improved by a factor of five.
I never thought I would hear about lead-acid batteries again. Traditionally, the chemistry isn't very finicky, but the cycle life is poor and the energy density is terrible. One bright spot in the chemistry is that the cells are easily recycled, with something like 97% of depleted cells being recycled.
Now this is a good engineering story. As we have debated hybrids and EVs, the issue has always been cost. The answer to the battery issue has always been lithium ion. This is not a technology I would embrace because of the cost.
By approaching the problem of cost rather than starting with a technology to apply, the EPS is solving the problem. I also like the hybrid lead acid and lithium ion idea. It is similar to a concept used in disk drives where a small solid state device is paired with a spinning drive to provide both speed and large storage at a lower cost.
Naperlou,, That's just what I've been saying for yrs. Start with reliable tech and then do what you are paid for, design a car around it that makes it work as a system.
Lead is a great battery, very cost effective when designed right. I'm about to go pick up some construction supplies in my lead powered Harley size EV trike pulling it's 14' trailer.
Fact is a 500lb composite 2 seat commuter/town car EV with 500lbs of quality lead deep cycle batteries can go 80mph and 100 mile range, though not at the same time, and be built for under $12k with a nice profit. But as these are not profitable, no rust, few parts to go bad, after the sale big auto and especially big oil hates them.
That said strings of 30 12vdc lead batteries in the article needs a BMS to keep them alive so if a li hybrid battery system now you need 2 complete battery BMS, etc plus cordinating electronics, it's better to replace the li battery with a small ICE like the Toyota X-1 though with lead, to give unlimited range.
Better is fewer cells, lower voltage like 100-120vdc of lead. Since a lightweight, very aero EV needs little power to go a mile one needs a much smaller battery pack to get decent range. My earlier EV sportwagon got 10 miles/kwhr or better. My Trike gets 20miles/kwhr shows what can be done.
Using forklift EV drive tech gives excellent performance at a reasonable cost.
EV's are selling. the Volt is not an EV but a hybrid, if they were not overweight, overteched, overpriced, they would sell.
As for battery life, lead with a good BMS will last 5-7 yrs then only needs to be rebuilt as almost 100% of them are recycled into new batteries. So one could just pay a reforming charge as no new materials are needed and have a new pack.
It's amazing how so many throw up such misinformation about how EV's can't work or limited when there are simple solutions.
So keep paying at the pump as it rises to $10'gal in 5 yrs. It only costs me a couple $/month for my transport fuel and I don't support oil dictators or terrorists it pays for.
Considering the announcement today that the Volt is losing $49K per car I have to wonder if the $12k for a battery pack is any closer to reality than the $40k retail price.
That statistic that Volt is losing $49K per car is quite shocking, Dennis. Obviously, that can't be sustained no matter how high government subsidies may be.
I suspect that the $40k retail price was chosen as the price they could eventually reach if development and volume go as per plan. Considering that the public has been reticent with $7500 off that number I think this will be a problem.
I agree, Dennis. This doesn't look promising unless that are some technical breakthroughs to lower the cost of building the Volt. It doesn't look like high-volume consumer purchasing is going to save the day.
Lead acid batteries have been around more than a century and even in high volume applications like SLI they still haven't been supplanted by alternative chemistries. These high performance batteries just don't scale and in the case of Lithium vs oil, all you're doing is trading the source of natural resources from one non-US friendly country to another.
Most people don't need 0-60mph in 4 seconds and 300 miles on a single charge, especially if the vehicle ends up costing more than their home. Build an EV or hybrid that competes with ICE in terms of cost per mile and TCO and you'll have a winner, irrespective of the source of electrons. Most people don't care if their cars run on gasoline, electric or the squeezings from baby seals - they just want a car that gets them from A to B in the most affordable way. EV's or any other alternative fuel will not succeed unless it's artificially mandated through law or solves an economic problem.
Ford is probably on the right track with their multi-drivetrain Focus. Remains to be seen if they can get the price point where it needs to be.
Good points, Contrarian. The drop off in sales of EVs, and the reluctance of hybrid owners to buy a second hybrid shows this market is presently very limited. It seems to me these vehicles are mostly for those who are interested in preserving the environment and have a few extra bucks to overspend on a second car. The price of gas isn't going to go high enough to justify the investment in an expensive gas saver. Hybrids and EVs will likely remain a small specialty market until technical breakthroughs change the present scenario.
The loss of $49K per Volt was poor analysis. That number is assuming all the cost are recovered in the first year, not spread out over production life.
Mixing battery technologies seems to have the potential to reduce costs without hurting overall performance. Aren't marine deep-cycle batteries lead-acid ? The lead-acid seems like the answer to acceleration, while the lithium-ion is there for range.
Gas / Lithium / Lead. I like it. It's a complicated problem we have, and I don't think there's a simple solution.
Charles, you could have titled your article "All that was old will be new again".
One poster said no one needs a car that goes 0-60 in 4 seconds and has a 300 mile range. I don't know who would give up a 300 mile range. If EVs / hybrids are going to be viable, they have to give us something close to what we have now.
This was a great article. It is exactly the type of thinking thats needed to draw hybrids away from the fringes and make them a reality for a broader range of vehicles. It's refreshing to see that someone has finally decided to drop the costly idealism associated with so many of these alternative technologies and is moving forward with technology that makes more sense economically.
Yes Bolder was a great tech but while putting amazing power, it wasn't likely to live long from not being able to keep them balanced. But in larger sizes say 70-100amphr cells with a decent BMS and you'd have serious EV battery pack material.
IIRC Bolders were only 2-3amphr cells made for cordless power tool battery packs. I like them there better than NiCads!! I remember Bill using them in his Killacycle drag bike hitting 8 second 1/4 mile times or so with them.
Facts are the better you design the battery to get power in, out as fast as possible like the Bolder, Optima and Orbital lead batteries have and you get excellent specific power and if you don't starve it of electrolyte and make it refillable you get more range and life.
Sadly most lead battery companies skimp on the interconnects raise cell resistance, etc, just to save a few cents!!
On my belt pack I have to carry I want Lithium!! Same power at 1/2 the weight!!
Interestingly the best lead batteries are about the lowest cost/lb like golfcart or true deep cycle traction batteries by good companies like Deka/East Penn, Trojan, USBattery. Going rate about $1.30/lb. So the 500lb battery pack for my example for 100 mile range costs only $700 or about $100-$140/yr
The original sub-c energy cell was rated for ~1 A/Hr with a discharge rate at 400 AMPS! That gave the Secure Start ( sold at Sears for the replacement for jumper cables in the trunk ) and the original Start Stick for aircraft the power. The cells could be recharged in minutes or seconds if you had the power generation capability...NO heat was generated during the charge/discharge cycle!
We had got the internal resistance and interconnects down to extremely low resistive levels by using wire braid on the cells interconnect system. Internal resistance was the problem with lead-acid technology; we had solved it with the TMF process and special winding machines.
As an aside, ROAR ( the R/C car association ) BANNED the Bolder Energy packs due to the power output they had. I still have a couple of the Bolder TMF R/C packs and the " energy cube " we made ( I'm looking at one now ) as well as my original SecureStart given to the employees as a Christmas Bonus....
I also was contacting the high power audio market to replace the capacitors used for smoothing the high current spikes of the multiple KILOWATTS of the car audio systems at that time.
I was thinking of the actual BATACITOR we created that was in SciFi literature of the time.
The military project was to build a 5 A/Hr energy cell that could be carried like a old fashioned cartridge belt you saw in the westerns. We were in the testing mode for these new energy cells when the company was outsourced. I know because I ran the Test Lab.
I had also worked on the Killacycle powerpack and " loaned " my XJ12 to test the product that became the SecureStart. That is how I got the 400 A figure.
On another robotics project, we worked on " intellegent forklifts " that could have their weight cut in half if Bolder Technology was still around.
One of the speculations I had was about the locomotives being able to use Bolder energy packs and the traction motors to save all the energy they wasted throwing away all that energy in the huge resistor grids on the top of the locomotives. That could save on the Diesel fuel consumption locomotives have.
The " what if " means that this conversation would have been happening over fifteen years ago.
oldtimer, the biggest problem is charging and balancing the cells thus the life of them. Most batteries don't die, they are murdered by over, undercharging or over discharging them. Sadly for the Bolder it wasn't very good at that.
You are right a big secret for not just lead batteries is low resistance interconnents and the paths to them from the active material. This cuts heat which causes most of lead batteries problems when not designed right/too cheap.
All lead batteries when fast charging, assuming good design, actually cool down until the 80%charge/gassing level. And don't slow down and even Bolders can explode. So while they like most lead batteries can charge as fast as they discharge, you have to be careful in the last 20%.
The Bolder or A123 are far superior to UC's in so many ways at a couple % of the UC's cost. Whenever I hear, read someone touting UC's I either see a con or gulible person as just not practical. Same about foolcells too.
I'm not sure about the math on this one... A bit of 'could you double check that math' is going on...
"Dhar says he could replace the 16-kWh lithium-ion battery in the Chevy Volt with a 3.5-kWh lead-acid battery and a 9-kWh lithium-ion pack. Doing so, he believes EPS could cut the battery pack cost of a Chevy Volt from approximately $12,800 to under $6,000."
So... 16kwh Li = $12,800 ($800/kwh-Li)
but... 9kwh Li + 3.5kwh Lead = $6,000? ($555/kwh-Li assuming $1000 for the lead/integration)
Hey Charles... i had thought about what Jerry is proposing... that lower output batteries might be the answer, I just didn't think that those would be that much cheaper per kwh...
Jerry...
As for cost we have been buying EV size lithium cells for $450/kwhr for a couple yrs retail so I don't expect it's costing GM even that. Add $100/kwhr for making it into a pack and BMS and you are at $550/kwhr.
But the claim here was reduction from $800/kwh so that's the starting point of the GM Volt's batteries right now.
Anyway, I can see where using a lead-acid battery to apply some punch at the starting block and then drawing slow and steady from the Li cells might be a good way to go.
First the pack is smaller in amphrs and likely in space because lower output lithium batts have a better wthr/lb by about 50% and generally cost less than high output ones.
Thus why having a hybrid pack helps by the lead batteries taking the power spikes, both acceleration and regen while being steadily charged by the lithium pack.
But I fail to see how with a smaller total amphr it can't lose EV range.
Interestingly just by switching the body to composites and cutting the engine down to 30hp range would about double from the weight savings!!
As for cost we have been buying EV size lithium cells for $450/kwhr for a couple yrs retail so I don't expect it's costing GM even that. Add $100/kwhr for making it into a pack and BMS and you are at $550/kwhr.
RalphyBoy, the answer to your question is below. The answer comes by e-mail from Subhash Dhar, CEO of Energy Power Systems. Note that Dhar cites the diminished need for thermal management. As we've reported many times, the National Academy of Engineering has estimated that about half the cost of today's lithium-ion battery packs lies in the packaging and thermal management system. Dhar is suggesting that some of that cost would be eliminated. See below.
Here is Dhar's response to your question:
"The Volt battery is designed for power and energy; it is assembled using three cells of 15 AH each in parallel to achieve 45 AH capacity; it also uses higher expensive conductive components to achieve power.
"In our hybrid battery the Li-Ion battery will not have parallel cells; these cells will be high energy cells without the need for higher power capability, which adds significant cost for thermal management.
"So the fewer number of higher capacity cells that do not have to deliver high power cost significantly less."
I've been in discussions about a much larger battery pack than the Volt has, a unit for a trolly car, and thermal management did seem to be the name of the game in that instance.
I also worked on an upgrade to one of our lines that includes at the max end a 180Ah 200lb pack. The upgrade... heat management. So, point well taken.
Most of the weight in a Lead Acid battery is the in the lead grid that supports the active chemicals. Firefly Energy tried to solve the weight problem by replacing the lead grid with a support made from carbon foam. They didn't succeed. I'm not sure of the reason. It might have been technical or it may have been the money ran out before all the details were worked out. They were a technology spinoff from Caterpillar Corp. They started out in Illinois and got a fair amount of support from private and government funding but still went belly up. A company in India bought the technology and as far as I know is still working to develop it.
Tesla Motors plans to roll out a “compelling, affordable electric car” that will sell for about half the price of its high-profile Model S by the end of 2016, company chairman Elon Musk said last week.
From Dell / Intel® New Paradigms in Design Work Scott Hamilton, vertical market strategist for Dell Precision workstations, 5/2/2013 5
Early in my career, I worked as a draftsman and remember the days of drawing on vellum with numbered pencils and Mylar with plastic lead. This was a fun experience in the sense that I ...
I've been using workstations for more than 10 years and love finding ways to get more performance from my system. With demanding professional applications that require more power each ...
A lasting memory from my first job as an engineer in an auto assembly plant is standing on hard concrete at six in the morning, vending-machine coffee clutched in hand, listening to ...
For industrial control applications, or even a simple assembly line, that machine can go almost 24/7 without a break. But what happens when the task is a little more complex? That’s where the “smart” machine would come in. The smart machine is one that has some simple (or complex in some cases) processing capability to be able to adapt to changing conditions. Such machines are suited for a host of applications, including automotive, aerospace, defense, medical, computers and electronics, telecommunications, consumer goods, and so on. This radio show will show what’s possible with smart machines, and what tradeoffs need to be made to implement such a solution.
To save this item to your list of favorite Design News content so you can find it later in your Profile page, click the "Save It" button next to the item.
If you found this interesting or useful, please use the links to the services below to share it with other readers. You will need a free account with each service to share an item via that service.
Tweet This
40 
