Conventional batteries combine the electricity-producing material and the reaction chamber into a tidy, sealed package. But this may not be the best way to power electric cars of the future.
Your Duracell AAs die when the materials inside can’t provide any more charge. Your Li-ion laptop battery (and conventional lead-acid 12-V car battery, for that matter) are rechargeable, but it still takes a while.
Flow batteries depend on introducing new material (usually a liquid) into the reaction chamber. A variety of advantages offset the more complicated plumbing.
MIT researchers suggest that instead of pumping gas into a car’s gastank, refueling an electric car could involve draining an exhausted solution and replacing it with recharged solution. The exhausted solution could be charged slowly, at the station, and the electric car would retain the same reaction chamber.
Instead of a liquid, they’re using solids in suspension. Read more about their semi-solid lithium rechargeable flow battery in a (well-written) news release: New battery design could give electric vehicles a jolt
or their paper in Advanced Materials: Semi-Solid Lithium Rechargeable Flow Battery
Photo: Dominick Reuter