The average electric car can drive 100 miles on a charge. That’s the main stumbling block preventing the wide scale acceptance of these clean cars. Better, longer-lasting batteries are a critical component of the clean energy economy. Now, German engineers are working on improving battery design. Electric cars have a collection of battery packs made of hundreds or thousands of individual battery cells that are wired together. The Germans are developing a new type of battery that reduces the number of components in a much simpler design that would free up space that could increase an electric car’s range to 1,000 km (621 miles).