"GM Says Latest Laptop-Battery Flareup Won't Burn Volt" Green Car Advisor

GM Says Latest Laptop-Battery Flareup Won't Burn Volt

By Bill Visnic, Contributor

Blackberrys throughout the auto industry lit up Wednesday when it was reported a laptop computer battery caught fire in South Korea.

Laptop fires aren’t exactly news anymore, but this is a bit more intriguing: the computer’s lithium-ion battery was manufactured by Korea’s LG Chem – one of two battery makers that General Motors Corp. has charged with developing the battery pack for a production version of its tirelessly-touted Chevrolet Volt hybrid-electric vehicle.

The last thing automakers want is even a whiff of safety concerns surrounding hybrid batteries.

Recurring incidences of lithium-ion battery fires in laptops is what led Toyota Motor Corp. to delay introduction of the new battery chemistry for its hybrid-electric vehicles – most notably the best-selling Prius – it was reported earlier this year.

But the Volt – and by association, its potential battery suppliers – is particularly under the microscope because of GM’s full-speed-ahead charge to develop the flashy plug-in hybrid in record time.

That includes a feet-to-the-fire program with its battery makers, because no volume-production hybrid or electric vehicle has yet used lithium-ion in the way planned for the Volt: a package big enough to give the car up to a 40-mile range strictly on battery power.

As chance would have it, shortly after news broke of the LG Chem-equipped laptop fire, Green Car Advisor happened to be on a plane with GM’s top battery authority, Denise Gray, director of hybrid energy storage systems.

Gray expressed concern about the incident, saying she had been in touch with officials at Compact Power Inc., the subsidiary of LG Chem that is working on the Volt battery contract. Gray said the laptop-fire situation "looks like it’s an internal-contamination factor."

She said that the manufacturing of lithium-ion batteries is done in virtually clean-room environments, much as with high-precision electronics such as computer chips. But even the highest safeguards can sometimes allow dust and other minor contaminants to slip into the manufacturing or assembly process.

Even a small piece of dirt or other contamination can be the root of a potential short-circuit in a single battery – or in a "run" of batteries if it occurs before the source is discovered and contained.

Gray says it’s important to know that the laptop battery is a "configuration totally different from the Volt battery design." She says there are several safeguards in the LG Chem lithium-ion battery design for the Volt to prevent a short-circuit in one module from overheating it and causing a chain-reaction in other battery modules. A laptop typically uses a single battery, while a hybrid vehicle might use a hundred or more.

Compact Power has said that its large-format design for vehicles uses manganese for its cathodes; manganese purportedly does not release fire-fueling oxygen when the battery hits high temperatures.

The company also said its automotive battery design uses special high-temperature separator membranes between the electrodes to minimize the chances of the "thermal runaway" that causes overheating batteries to catch fire.

Nonetheless, Gray admits, "I am concerned. I think we [automakers and battery makers] all recognize that it's all the same from a consumer perspective."

All parties "have to help each other to make the technology more robust," she said.

Gray said that joint development with battery makers on such programs like the Volt’s will be beneficial for all.

Battery makers will learn from the testing, analysis and development procedures that automakers must embrace – and from the high degree of responsibility intrinsic when talking of safety in the auto industry. Although laptop fires are a potentially dangerous situation, most consumer-electronic failures have nothing near the potential consequences of equipment failure in automobiles.

Automakers, in turn, will learn from the production experience of the battery makers, who every year manufacture hundreds of thousands, or perhaps millions, of batteries in laboratory-grade environments.

Brett Smith, assistant director of the manufacturing, engineering and technology group at the Center for Automotive Research, doesn't think the laptop fires will hurt the auto industry's battery programs or the chances of upcoming hybrids and electric cars.

By the time the Volt or other hybrid-electric vehicles using lithium-ion batteries are ready for showrooms, consumers predisposed to buy those vehicles will be "very technically savvy" – and will understand, as GM’s Gray says, that the automotive lithium-ion batteries and laptop batteries are two different animals.

He did say, however, that LG’s battery formula, lithium cobalt oxide, is generally believed to be more susceptible to thermal runaway than the nanophosphate chemistry used by A123 Systems, the brains behind the other lithium-ion battery supplier competing for the Volt contract.

Smith also said that once high-volume manufacturing of automotive lithium-ion batteries begins, most manufacturing-related quality issues – such as the contamination that presumably caused the recent LG laptop-battery fire – should be ironed out.

The battery factories are likely to be highly automated, he said, reducing the need for human labor and the resulting opportunities for random contamination of the manufacturing environment.