Clever cathode design opens doors to first rechargeable calcium battery

The first working rechargeable calcium–oxygen battery has been developed by a team in China. The prototype device was charged and discharged over 700 times at room temperature and the team believes the battery’s superior performance derives from an efficient two-electron redox process, facilitated by a specific combination of electrode and electrolyte materials.

Calcium is the most abundant divalent metal on Earth and these batteries could theoretically offer a cheaper and more energy dense alternative to lithium-ion batteries. However, calcium’s larger atomic radius and higher charge creates numerous problems that still need to be overcome to create a viable battery.