New lithium-ion batteries are also safer and less expensive than those in a laptop. One of the companies under contract with GM to develop battery packs is A123 Systems, based in Watertown, MA. It has developed a nanostructured iron phosphate-based electrode that is much safer than the cobalt-oxide laptop batteries that were recalled last year. For example, while a cobalt-oxide battery will burst into flame if punctured by a nail, the A123 battery merely releases innocuous wisps of steam. (See “Safer Lithium-Ion Batteries.”) A123 is already producing millions of its batteries for use in professional power tools, and now it has developed a new, larger cell designed to be more rugged and hold more energy. The company has also modified the electrolyte to make the battery able to operate very well at -20 ˚F or temperatures up to 140 ˚F. As a result, “the car can operate in Scandinavia, in Patagonia, or in the summer in the middle of a tropical city,” says Ric Fulop, cofounder and vice president of business development at A123 Systems.
At this point, cost may still be an issue. But that will change as more of the cells get made. “At the end of the day, it’s a scale game,” says Alan Mumby, CEO of a joint venture between Johnson Controls, in Milwaukee, WI, and Saft, in Paris, France. The venture has been awarded one of the two contracts for developing battery packs for GM .
Overall, “the fundamental tool kit–the weight, volumetric efficiency, the demonstration of life in a lab basis, and safety through extensive testing–have all
been demonstrated,” says David Vieau, president and CEO of A123 Systems. “So this is not a pie in the sky. However, the actual execution of all functionality in cells in actual vehicles hasn’t been done.”
Although integrating the batteries into large packs is a challenge, in fact it has been done before. According to Scott Lindholm, vice president of systems engineering at Cobasys, based in Orion, MI, which is teaming with A123 Systems on the GM contract to develop battery packs, many of the problems involved in making lithium-ion battery packs are similar to those the company has already solved for the nickel-metal hydride packs it already produces for GM hybrids. What’s more, several companies have already made large lithium-ion battery packs for vehicles. For example, Hymotion, based in Ontario, has used A123’s power-tool batteries to make kits for converting the Toyota Prius into a plug-in hybrid. Indeed, its design is one of the contenders for converting hundreds of New York State’s government-owned hybrids into plug-in hybrids. These packs are smaller than that used in GM’s Volt concept vehicle, but companies such as Tesla Motors have already successfully engineered lithium-ion packs that are a few times larger than GM’s pack.
The question is whether such packs can be engineered to have the life, safety, and cost that GM wants. As it is, these battery packs can cost tens of thousands of dollars, placing them out of the range of most consumers. But part of the cost has to do with scale, and that should change if GM puts the vehicle into production. The price is also coming down as the batteries are used in other applications, such as power tools.
In all, it seems as though battery technology is falling into place, just as demand for more fuel-efficient cars is rising. “It’s really exciting for us to be in this business,” says Fulop. “The timing ended up quite nice. We developed these products, and the plug-in-hybrid thing is really happening.”