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Top industry figures says there's no sure fire method of predicting internal shorts

For the last two decades demand for lithium ion batteries in mobile devices has exploded, but so did safety concerns.  Apple, Inc. (AAPL), Sony Corp. (TYO:6758) and several others struggled with exploding or smoldering products.

I. Expert Panel -- How to Make Batteries Safer

Now it's the transportation industry that is grappling with these issues.  This week a panel of experts met at a forum sponsored by the U.S. National Transportation Safety Board in a bid to answer the question of how to prevent the wave of battery fires that have swept the electric vehicle and commercial aircraft industries.

The answers were not terribly reassuring.  While experts said the issue of short-circuits was known and best-practice preventive measures were included in most large battery systems, that there's no sure-fire method of protecting a battery from its own internal flaws.  


And the mechanism by which short circuits start fires is still poorly understood.  Laurie Florence, principal engineer at international battery safety certifier UL, says that you can shoot a nail into most lithium ion batteries, triggering a short circuit, but no fire.  However, more subtle internal design issues can trigger short circuits that do lead to fires.

Daniel Doughty, president of Battery Safety Consulting, urged the industry at the forum to embrace research into design isolated cell technology that prevents a fire in one cell from spreading to the next.  He also urged industry leaders to develop better technology to diagnose and predict internal short circuits.

Battery manufacturers already rely on a cruder fault prevention technology -- additives.  The liquid lithium ion fluid -- roughly 25 percent of the contents of a typical cell -- is highly flammable.  Typically additives are mixed into this volatile liquid to reduce the fire risk.  But these additives also frequently reduce the power capacity/delivery of the battery, hence raising costs and cutting battery life.

Janet McLaughlin, deputy director of the U.S. Federal Aviation Administration's hazardous materials safety programs, comments, "We all know lithium batteries are hazardous materials."

On the other hand, replacing batteries also isn't cheap.

II. Battery Fires Hit Boeing, GM, Hard

Both Airbus, a subsidiary of The European Aeronautic Defence and Space Company N.V. (EADS) (EPA:EAD), and The Boeing Company (BA), the world's top two commercial aircraft companies, initially tapped lithium ion batteries for auxiliary power systems in their new flagship aircraft, an industry first.  Airbus recently dropped plans for lithium ion batteries in its upcoming A350 after backpedalling amid fire concerns.

Those concerns allude to rival Boeing's efforts, which are still forging ahead despite major setbacks.

In January the battery module in the Dreamliner 787 caught fire in Boston, Mass. while on the ground.  Just a couple weeks later, a Dreamliner in Japan was struck by a serious battery fire.  After the second incident Boeing agreed to ground the Dreamliner and search for a solution.
 

Boeing 787 production line [Image Source: Boeing]

Since then, Boeing has redesigned the battery module.  And while an investigation into the previous fires is still ongoing, the FAA has agreed to permit Boeing to start testing the new module.

The auto industry has also been struggling with battery issues of its own.  Fisker suffered a pair of fires last year, although the company insists they weren't battery related.  But General Motors Comp. (GM) did trace fires in its Chevy Volt electric vehicle back to malfunctions, triggering a quasi-recall.  In the aftermath of the recall GM executives were forced to testify before Congress.  GM recently acknowledged that the publicity from the fires hurt Volt sales.


Chevrolet Volt [Source: TECHVEHI]

But again, in automotive applications automakers are struggling with the delicate game of risk regarding batteries and additives.  Fewer additives might give customers more miles on a charge -- but they might also cause a fire.

III. Soft Demand Tempts Some to Cut Corners

A final issue is soft demand.  The struggles of electric vehicles -- caused in part by poor battery range and public awareness of battery safety issues -- have cause the industry to badly miss sales growth predictions.

In 2002 only 800m lithium ion cells shipped.  This year roughly 5.5 times that total -- 4.4b cells -- shipped.  Glen Bowling, vice president of sales at Saft Specialty Battery Group, a producer of lithium ion batteries, comments to Reuters, "The growth in the mission of lithium-ion batteries is substantial. It's a stretching of the technology boundaries and we have to be professional when we do that."

But the industry is also hurting.  Massachusetts Institute of Technology materials engineering professor Yet-Ming Chiang comments, "[2008-era predictions of 2011 demand] were off by more than a factor of 10.  This created a great deal of stress among those who manufacture batteries.

Battery product
LiIon battery-makers have been under increasing financial stress amid missed sales targets.
[Image Source: ANL]

Those miscalculations have caused manufacturers and startups to load up on expensive lithium metal and overproduce.  Professor Chiang says there's enough idle lithium cell stock to power 400,000 LEAF EVs from Nissan Motor Comp., Ltd. (TYO:7201).

Many companies have gone out of business.

Amid that market it may be tempting to the survivors to cut corners.  Survivors are desperate that Congress will back a fresh round of $7,500 to $10,000 USD electric vehicle tax credits proposed by President Obama to stimulate asales.

Sources: NTSB, Reuters



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Flame out
By Ammohunt on 4/12/2013 3:45:13 PM , Rating: 2
Perhaps they can come up with a non-flammable electrolyte? might be a good start.

I wonder if the shorts in the battery are caused by impurities in the lithium introduced during refining of the metal.




RE: Flame out
By Bad-Karma on 4/12/2013 7:13:01 PM , Rating: 5
Brawndo ! Its got electrolytes... Its got what batteries crave!


RE: Flame out
By Totally on 4/12/2013 7:43:55 PM , Rating: 2
If it readily gives up electrons it burns so there isn't such a thing. Everything will combust if enough is heat or energy applied to it, which is what is happening to these batteries from the large amount of heat generated due to the internal shorts.

To answer your question, no, at least not directly.


RE: Flame out
By BRB29 on 4/15/2013 11:34:23 AM , Rating: 2
we need to stabilize those electrolytes with a flux capacitor!!! Then we can increase energy density so that a single AA battery can power a real light saber or phaser.

If you ever read anything about energy storage then you'll high density energy storage is no different than explosives.


RE: Flame out
By HrilL on 4/15/2013 12:19:50 PM , Rating: 2
I used to work for a company that was working on Zinc and silver ion batteries. They produced the same amount of power and made great single charge batteries as they can last for 25-30 years without losing a charge. They are also safe and non hazardous. The one real problem is they were never able to get the recharge cycles up. After 80 cycles they'd be at 80% of the full charge and after 250 cycles they'd be at 50% charge. If they were able to get their cycle count up then they might have a good safe replacement.


Manufacturing
By mrwassman on 4/12/2013 4:51:14 PM , Rating: 2
I suspect manufacturing and ignoring certain thermodynamic principles.




RE: Manufacturing
By Motoman on 4/12/2013 6:47:07 PM , Rating: 3
I don't think anybody's "ignoring" anything.

The problem is trying to make a battery pack provide the highest performance within the smallest volume of area. If you wanted "perfect" batteries that you could guarantee 100% that they would never fail, they'd probably be twice the size and half the power. If you wanted maximum power and density, all else be damned, you could probably make the batteries be even smaller and provide even more performance - but they'd blow up all the time.

These manufacturers have to dance a delicate dance. I don't know what the actual physical problems are with the battery tech, but I imagine them running into something analagous to CPU foundries with the problem of electron migration. The smaller your processes get, the more electron migration happens. At some point, the electron migration with completely invalidate the CPU entirely. What can you do about it? Mmmm...change the laws of physics?


RE: Manufacturing
By Shig on 4/13/2013 3:47:28 PM , Rating: 2
Tesla Motors and SpaceX are both using a battery technology that the other guys are not. They should probably give Elon Musk a call because his power-train is years ahead of the others.

It's pretty obvious now that there are battery designs that work and those that do not. Redesign your frickin batteries if they're having problems.


RE: Manufacturing
By maugrimtr on 4/15/2013 8:39:16 AM , Rating: 2
This should be where the free market kicks in and corrects the imbalance. Which it slowly is. Tesla are performing extremely well while competing EVs have suffered lost sales. That seems to be recovering now that the initial fire scare is over. Fisker is, quite rightly, the obvious loser so far. Given the market growth in EVs, I'm getting worried about the proposed 10k tax credit thing. The current 7.5k has done its job - expanding it doesn't seem necessary.


RE: Manufacturing
By Shig on 4/15/2013 1:39:53 PM , Rating: 2
I don't think we should eliminate the tax credit until a mass market EV comes out. We're still 3-4 years away at the earliest.


toyota avoided the tech & now we see why
By jackpro on 4/15/2013 9:17:36 PM , Rating: 2
there was a reason toyota have stuck with nickel metal hydride




RE: toyota avoided the tech & now we see why
By foxalopex on 4/16/2013 9:33:55 AM , Rating: 2
No Toyota did not use NiMH batteries because they were less likely to short-circuit. They used them because:

1. A Prius hybrid doesn't use batteries as primary driver, just mostly for acceleration. NiMH batteries are very good at generating burst power. You can easily damage Lithiums trying to do the same but in an EV the Lithium battery is so huge that it helps prevent this issue.

2. A short-circuit and resulting fire can affect any battery. Short circuit a lead acid battery in a regular car sometime and see what happens then if you don't believe me. The only EV to have caught on fire in the real world so far was the Fishker and that was due to a cooling fan getting jammed I believe which caused some non-battery part to overheat and catch on fire. (Embarrassingly bad design if you ask me.)

3. NiMH are cheaper than Lithiums but they don't store as much power as a NiMH. This is why you don't see a NiMH in cellphones. You can't build a small and thin cellphone and expect the battery to last if you use NiMH.

4. Power density is a major issue for EVs. I own a Chevy volt and the 500 lb lithium battery pack is equivalent to about a gallon of gas. (If you run the Volt on gas, it gets roughly the same distance.) Considering that the gas engine is very inefficient, this means the battery pack has in reality even less energy than a gallon of gas. A gallon of gas doesn't weight 500lb last I checked. This means for EVs the push is for more power in less space so that's why almost all EVs use Lithium batteries. A hybrid doesn't because it is gas powered. A car meant to be electrically powered almost universally uses Lithium for this reason. (ie Prius Plug-In)


By jackpro on 4/17/2013 10:29:04 PM , Rating: 2
learnt something thanks


New technology needed
By yik3000 on 4/12/2013 4:00:37 PM , Rating: 2
IMO we need a new battery technology desperately. I often read some post about awesome material that can make battery greener, thinner, lighter, holds more charge, recharge faster, last longer...wonder when those goodies will ever make it to the consumer market.




RE: New technology needed
By kmmatney on 4/12/2013 5:35:59 PM , Rating: 2
For it's purpose (to provide better gas mileage) the old NiMH battery in the Prius was pretty awesome. I was really surprised by this consumer reports study:

quote:
Battery life cycle As the Prius reached ten years of being available in the U.S. market, in February 2011 Consumer Reports decided to look at the lifetime of the Prius battery and the cost to replace it. The magazine tested a 2002 Toyota Prius with over 200,000 miles on it, and compared the results to the nearly identical 2001 Prius with 2,000 miles tested by Consumer Reports 10 years before. The comparison showed little difference in performance when tested for fuel economy and acceleration. Overall fuel economy of the 2001 model was 40.6 miles per US gallon (5.79 L/100 km; 48.8 mpg-imp) while the 2002 Prius with high mileage delivered 40.4 miles per US gallon (5.82 L/100 km; 48.5 mpg-imp). The magazine concluded that the effectiveness of the battery has not degraded over the long run.[127] The cost of replacing the battery varies between US$2,200 and US$2,600 from a Toyota dealer, but low-use units from salvage yards are available for around US$500.[127] One piece of research indicates it may be worthwhile to rebuild batteries using good blades from defective used batteries.[128]


Ha!
By Sazabi19 on 4/12/2013 4:04:04 PM , Rating: 2
quote:
Top industry figures says there's no sure fire method of predicting internal shorts


I see what you did there :)




By Prosthetic Head on 4/14/2013 2:04:30 PM , Rating: 2
Should be using LiFePO4 electrode materials, especially for applications where safety and reliability are important. It has a somewhat lower capacity than LiCoO2 fresh off the manufacturing line, but after a year on the shelf or 50 charge cycles or a few temperature changes it has a much higher real capacity. It is also intrinsically safer, the structure is much more stable and it won't release oxygen which causes fires when overheated. It is also less toxic.

I really don't see why this battery chemistry has been neglected. I suspect its purely marketing departments don't like the lower off the shelf energy density than LiCoO2, even though in reality most users will get much longer battery life throughout its lifecycle.

Is it just another dangerous triumph of marketing over technology or does anyone know a good reason it's not more widely used?




Boeing answer
By DockScience on 4/14/2013 8:39:06 PM , Rating: 2
Boeing has the answer, just place all lithium batteries in a fire proof box (we can call it a fireplace) and install a chimney.

Steampunk laptops and cellphones for sure.




By foxalopex on 4/15/2013 9:19:39 AM , Rating: 2
Testing has already shown that the volt's battery pack will only burst into flames if ALL three events happen to you:

1. Involved in a side-impact strong enough to total the car.
2. Somehow manage to roll the car over in the crash too, again your car's probably a write off.
3. Decide not to discharge the battery and stay in the car for three weeks. Which probably means you're dead to begin with. XD

In response to this GM decided to provide optional bracing in the battery to help prevent the battery from being punctured in side impacts which last I heard most owners didn't even bother with because the chances of all that happening are low.

A more likely problem is your house having a substandard electrical system and a house fire starting due to bad wiring which can't really be blamed on the car.

Personally I think the volt's as safe as any regular gas powered car. It's not like gas doesn't burn either and some folks have even gotten themselves torched trying to fuel their cars.




By malfunctions, you mean
By Masospaghetti on 4/15/2013 10:22:48 AM , Rating: 2
quote:
[GM] did trace fires in its Chevy Volt electric vehicle back to malfunctions


You mean they didn't design it to be flipped over multiple times and left sitting in a warehouse for weeks, without the battery being discharged? The incident hurt Volt sales because of a hyperactive media, not because of a technical flaw.




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