Will Boeing’s 787 Battery Issues Ground Electric Vehicles, Too? [View all]

[kristopher]

Will Boeing’s 787 Battery Issues Ground Electric Vehicles, Too?
Ryan Matley
Consultant
February 4, 2013

Boeing has made big news in recent weeks, but for all the wrong reasons. The Federal Aviation Administration (FAA) grounded Boeing’s flagship airplane, the fuel-efficient, next generation 787 Dreamliner. The problem isn’t its innovative carbon fiber construction, but rather a less heralded technologic leap: lithium ion batteries. In the span of one week a battery caught fire while a plane was at the gate in Boston and another forced an emergency landing and evacuation in Japan when it overheated. This marks the first grounding of an airplane type since the DC-10 in 1979.

Inevitably, news stories appeared connecting the 787’s battery troubles to past laptop battery fires and electric vehicles (EVs), reflexively highlighting the 2011 Chevy Volt fire that occurred following crash testing.

...Unlike electronics and aerospace batteries, electric vehicles do not use LiCoO2 chemistry, specifically because of its safety concerns. (Some 2,500 early Tesla Roadsters used LiCoO2 batteries designed with multiple safeguards, but the company has since switched to batteries with more stable chemistries.) Automakers have intentionally traded less energy density for better safety and lower cost (cobalt is expensive). Most electric vehicles or plug-in hybrids on the road use a lithium-manganese-spinel (LiMn2O4) chemistry. Some are adding a nickel-manganese-cobalt chemistry developed at Argonne National Lab to increase energy density.

...Does more stable lithium ion chemistry combined with the robust design of automotive batteries mean a 787-style battery meltdown will never occur in an EV? Of course not. The precise reason that lithium-ion batteries are used—their high energy density—increases the odds of a sudden energy release (aka fire). But that doesn’t mean electric vehicles are any less safe than internal combustion vehicles. For the last one hundred years cars have been carrying around gasoline, which has more than twice the energy density of lithium ion. Automakers have been able to minimize, but not eliminate (see the Ford Pinto) the risk of fire due to fuel leaks. In fact, I might prefer the on-road safety record of current automotive lithium-ion batteries, which have had zero reported fires in over 500 million miles driven. By comparison, gasoline vehicles have averaged nearly 65,000 vehicle fires that caused 300 fatalities per year between 2008 and 2010.

http://blog.rmi.org/blog_2013_02_04_Will_Boeings_787_Battery_Issues_Ground_Electric_Vehicles