“Lithium-air batteries excite alternative energy fans because they can store up to ten times the energy of today’s lithium-ion batteries, an energy density similar to that of gasoline. But skeptics note that lithium peroxide by-products in the lithium-air reactions quickly contaminate the cathode, killing the battery, and the open design required to get enough air to the reaction point for efficiency poses problems.” – Christine Lepistro / Treehugger.com