AFSCME 3357-HOF'S BLOG

What are Lithium Phosphate Batteries?
Why should you care?

In recent parallel announcements, Toyota announced that it was postponing a planed 2009 introduction of a plug-in hybrid car from 2009 to 2011. At the same time, General Motors announced that it was on track to introduce a plug-in hybrid in 2009, with an advanced model by the end of 2010. The problem is that Toyota needs more time to develop the Lithium-ion batteries that make the car practical. It's possible that Toyota has bet on the wrong horse, scientifically speaking that is.

Toyota's batteries use a lithium-cobalt oxide technology similar to that used in laptop batteries. As you are probably aware, there have been a lot of recalls of laptop batteries due to fire and overheating. What is dangerous in a laptop is stunningly dangerous in a car that can travel 120 mph, and subject to being hit by other cars going 120 mph.

This is one area that General Motors may be one up on Toyota. General Motors, as showcased in its Chevy Volt showcar, is doing its best to sell a plug-in hybrid in the 2009-2010 timeframe. GM uses a different battery chemistry, a chemistry based on a Lithium-Phosphate mix. Lab tests have shown that lithium batteries using phosphate is much less prone to catching fire than batteries using cobalt.

General Motors' battery technology is from a company named A123. I have previously blogged about a similar technology by a company called Valance Technology. Valance seems to be falling a bit behind as far as I can tell, but any company could be just one patent away from a breakthrough.

There is one more variable in the mix: If any lithium technology is so much more expensive than the NiMH technology currently used in hybrid cars that the cost outweighs the marginal benefits, it's possible that no lithium batteries will be successful. Toyota still plans to introduce its next generation Prius hybrid for the 2009 model year, in late 2008 or early 2009.