Iron Power: Eking more juice from batteries

Many of the rechargeable batteries that power cell phones, laptop computers, medical implants, and hybrid cars contain some of the same electrode technology that was used in Thomas Edison’s day. Now, chemists have come up with a modern alternative that could potentially multiply the capacity of such batteries.

A battery typically consists of two electrodes—a positive cathode and a negative anode—immersed in a substance through which charged atoms, or ions, can flow.