Editing Energy storage (section)

===== Flow battery =====
{{Main|Flow battery|Vanadium redox battery}}

A [[flow battery]] works by passing a solution over a membrane where ions are exchanged to charge or discharge the cell. [[Electrode potential#Potential difference of a cell assembled of two electrodes|Cell voltage]] is chemically determined by the [[Nernst equation]] and ranges, in practical applications, from 1.0 V to 2.2 V. Storage capacity depends on the volume of solution. A flow battery is technically akin both to a [[fuel cell]] and an [[electrochemical cell|electrochemical accumulator cell]]. Commercial applications are for long half-cycle storage such as backup grid power.