Lining up those cells and sandwiching them between an insulting material, a four-millimeter cube could produce three volts of electricity, enough to power a retinal implants, for example.

• 如果把这些电池串联起来，夹入绝缘材料之间，四毫米大小的电池组就能产生三伏的电压，足以为像视网膜植入体这样的装置提供电力。