Following the lead of Nissan and NEC, which both recently have started down this track, the German carmaker is looking into lithium-ion batteries to improve its hybrids and electrics. It sounds like the Nickel-metal hydride (NiMH) batteries in their cars are both heavier and more toxic than the alternative.

The Li-ion batteries would lower the weight of the car by hundreds of pounds, improving handling and mileage. You’ve already got them in your phones, media players, and so on, but adapting them for the high-capacity, high-throughput application of powering a car is a serious endeavor — which must be why Sanyo is pledging nearly a billion dollars over the next couple years to developing the technology.