A123 Updates Next Gen Nanophosphate EXT Batteries – Solves Lithium Battery Heat Issues

SEP 12 2012 BY JAY COLE 17

A123 Grid Storage Solutions May Also Greatly Benefit From New EXT Technology That Allows For Operation In More Extreme Temperatures

Not too long ago, but before A123 almost went out of business and was saved by a Chinese automotive parts maker, they announced they had perfected a disruptive new battery technology called Nanophosphate EXT.

A123 Systems Employees Perform Quality Check On A Lithium Ion Battery Pack (We are guessing this was taken after the Fisker Incident)

This new battery technology in A123’s labs was shown to improve power capability at low temperature and life at high temperature, a problem that is currently confounding Nissan LEAF management in the extreme heat of Arizona.

Nanophosphate EXT is expected to deliver increased performance and reliability while minimizing complexity and reducing total cost of ownership (TCO) over the life of the battery system.”

At the time of the announcement three months ago, A123 said that battery chemistry would allow for 20-30% higher power at lower temperatures than their existing Nanophosphate batteries, while also giving “superior power retention.”  Under normal conditions, early testing had shown a 90% retention of initial capacity after 2,000 full charge cycles.  Even at 45C (113F), it took almost 800 full cycle discharges for the pack to lose 5%, 1,600 cycles for 90%.

However, the internal temperatures that is currently crippling LEAF batteries in Arizona, and some parts of Texas and California, is even higher than that.

Thankfully, A123 has not only done more tests at even more extreme conditions on their Nanophosphate EXT batteries, they have also lent out cells to Ohio State University (OSU) to independently verify their results.  And to say the results are encouraging is an understatement, they are ‘throw away your thermal battery management system’ good.

“In high-temperature testing, A123’s Nanophosphate EXT cells are exhibiting a rate of aging that is about three to four times lower than cells from a competing manufacturer of commercially available lithium ion technology. Specifically, in testing conducted at 75 degrees Celsius (167 Fahrenheit), A123’s Nanophosphate EXT cells are showing more than twice the life compared with the competition after about 700 full DOD cycles (at an aggressive 4C discharge rage). “

Who Needs A Thermal Battery System When You Have Results Like This? (Click To Enlarge)

Just to repeat, that is 167 degrees Fahrenheit they are testing these pack ats; hotter than any recorded temperature on Earth.   And under these extreme condition, after 700 full cycles, the pack is still retaining 90% of life.

In “LEAF miles” that would be 90% retention after 50,400 clicks, in 167 degree weather.

The competition, which is clearly  the LMO (lithium manganese oxide) cells found in the Chevy Volt and Nissan LEAF, faired much worse, losing over a third of their capacity.  It should also be noted that drop off on the curve for ‘the competitor’ is extreme even at 65% left.

And low temperatures? A123 has got that covered too:

“In low-temperature testing, a battery built with A123’s Nanophosphate EXT cells is delivering up to as many as 1,200A at minus 18 degrees Celsius. This effectively eliminates the only performance advantage of absorbent glass mat (AGM) lead acid batteries (which deliver approximately 800A at minus 18 degrees Celsius) for micro hybrid vehicles and improves the total cost of ownership (TCO) of A123’s 12V Engine Start battery versus AGM.

Even more important than lab results is real world production.  A123, now flush with Chinese capitol, see volume production in the first half of 2013.

A123 has hosted a podcast featuring Yann Guezennec, professor of mechanical and aerospace engineering at OSU and a senior fellow CAR, and John Neal, a research engineer who manages CAR’s battery characterization and its aging laboratory, discuss the testing results thus far.  You can listen to that podcast here.

A123 closed Tuesday up 6 cents, or 25% to close at 29 cents, still well at the lows of its trading range for this year (.19 – $5.19), and up another 24% on Wednesday to end the day at 36 cents. Real time quote can be found here.

Disclosure: The author of this piece (sadly) has a position in LEAP call options of A123.


A123 Prismatic Battery Modules For Plug-In Automotive Applications


Categories: Battery Tech, General, Nissan


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17 Comments on "A123 Updates Next Gen Nanophosphate EXT Batteries – Solves Lithium Battery Heat Issues"

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Pumper! 🙂

Good story – this is the kind of battery the EV industry neads. Sure, the Volt and others have TMS – but imagine the costs saved without? If the EXT can run well in cold temps and not die in hot temps (nee Leaf) then this is a good solution for EV, Grid storage, Cell tower backup batts, stop-start and many more solutions. I hope the company survives to make this come to market.

Jay Cole

I need to get this bad boy up to like $10 so I can buy a InsideEVs private jet, (=

Marc Lee

If this technology makes it to production that will be awesome. And the TMS on my Volt and Focus Electric will be on display in the Smithsonian as the Wild West days of early EV production.

What I am still trying to figure out is why did we (via the gov’t.) pump hundreds of millions into this company, and then allow it to be bought on the cheap by the Chinese? Who will undoubted take the technology and the jobs back to China and build it there for sale to us by the container load a year or so from now?


A123 has had factories in China for years, the tech was stolen years ago and that is why LiFePO4 is so popular in China.


you are wrong. a123 are produced in USA and Korea. other are fake having normal 800 cycles and low discharge rate.

Anthony Fiti

But are these batteries (even without a TMS) energy dense enough to put in an EV? Driving 50,000 miles to 90% power is good, and assuming linear degradation, buying a new pack every 100,000 miles doesn’t seem unreasonable – assuming packs come down in price. And after 6-8 years you’d probably want a new pack anyways given increased range and performance that will come with it.


That 90% degradation at 50k km is at 75 deg C. It is assumed that no-one will actually experience that high temperature, especially over the entire life of the car. The article states that under normal temperature, 2000 cycles can be expected at 90%. This equates to 149k km or 90k LEAF miles. If we extrapolate that to the usual 80% then 180k miles, or near normal life of a car. At this point the car would be worth less than the price of a new battery pack.

Eric Cote

This is good news, and the breakthrough I read about previously that seemed like a good pairing for USPS long life vehicle upgrades that are planned. Too bad A123 is refusing to sell batteries to “conversion” companies.

Rant aside, I would also like to know what the plan to sell these at, from a $/kWh standpoint. They do mention they’re cost competitive, but I’m not sure if that’s playing games with factoring in TMS costs, additional battery buffer zones in “traditional” EV batteries, etc.

Jay Cole


As of yesterday A123 is starting to sell direct. Not a lot of product online yet, but at least they started:

I was going to roll a story on them starting to sell direct, and the Chinese company loosening them up, but didn’t figure the wider audience would get much out of it. Glad you asked though, 9=

Eric Cote

Will they sell their 23kWh pack direct yet? I thought that was only for OEM’s, which is what was prohibiting conversion companies from accessing this technology.

The 23kWh pack is of interest to me because it’s made up of two smaller, 11.5kWh subsystems. And if these can truly be fully dischanged to thousands of cycles, an 11.5kWh pack would be a great option for a rural delivery fleet. Do we have any of those in the US? 😉

Eric Cote

Edit: I see it’s the 12V batteries they’re offering. Like you said, it’s certainly a start, and a move in the right direction!

Dave R

You should roll the story – lots of people interested don’t know this yet, but know that A123 makes some of the most durable batteries available…


Selling direct? Is this April 1st? AONE? No way!

I’ll buy one to hold down my pile of AONE shares.


How much would 16KW weigh?


George Bower

That’s my question also. My guess is that these batteries are heavy.


I would really like to see Nissan test these batteries out on our dying Nissan Leafs here in Phoenix. Anything would be better than the sorry, depleted range we have now, and since we are apparently guinea pigs already, I’ll try a new pack.

Arizona EV Pilot

Jay! Bravo sir! Great artical! The first thing I thought after reading this was, “wow, that is more information in this short news story than in ALL of the vague and misleading info Nissan gave us in Arizona befor we purchased our leafs”. Been an owner for almost year and this is news to me. Shame on Nissan for selling a EV that will not hold up in Phoenix per its advertisements. Glad this chineese company is inovating and letting 3rd parties verify their findings. Hurray Jay for doing real and honest reporting!