A Stirred Self-Stratified Battery for Large-Scale Energy Storage

Large-scale energy storage batteries are crucial in effectively utilizing intermittent renewable energy (such as wind and solar energy). To reduce battery fabrication costs, we propose a minimal-design stirred battery with a gravity-driven self-stratified architecture that contains a zinc anode at the bottom, an aqueous electrolyte in the middle, and an organic catholyte on the top. Due to the solubility difference, the positive redox species are strictly confined to the upper organic catholyte. Thus, self-discharge is eliminated, even when the battery is stirred to realize high-rate charge-discharge. Moreover, the battery intrinsically avoids electrode deterioration and failure related to membrane crossover suffered by other types of cells. Therefore, it exhibits excellent cycling stability, which is promising for long-term energy storage.