In my last post I mentioned nanotechnology as one avenue being explored as a way to make batteries that recharge faster. I may have misled by failing to mention a completely different approach that is on the way, perhaps sooner than nanotech batteries. If you imagine an electric battery that is recharged not by adding electricity but by putting in fuel, then what you have is a fuel cell. The consensus of engineers is that the fuel of choice is hydrogen gas, resulting in a term I am sure you have heard, a hydrogen fuel cell. Despite the different name and some differences in the construction, a fuel cell puts out electricity in essentially the same way a battery does. Hydrogen fuel cells have been around for years and have been much talked about, and now, the first mass production fuel cell cars are on the way next year. The first hydrogen fuel cell cars will cost about the same as a comparable battery-powered electric car, and surely within a few years we will have a good sense of how well fuel cell cars are doing.