Achieving a stable zinc electrode with ultralong cycle life by implementing a flowing electrolyte

Abstract

Zinc electrode stability is one of the major problems that restrict the wide application of secondary zinc-based batteries. In this work, the impacts of flowing electrolyte on the suppression of zinc dendrite are systematically investigated through experimental and numerical investigations. In a static electrolyte condition, the stability of the zinc electrode increases with an increase of the applied current density. In the presence of flowing electrolyte, the lifespan of the zinc electrode at the current density of 10 mA cm−2 increases dramatically from 900 cycles in the static electrolyte to 2580 cycles with a flow rate of 30 rad min−1, and further increases to 4725 cycles when increasing the flow rate to 50 rad min−1. Moreover, by changing the inlet flow direction from the side to the bottom, a more stable electrode with the lifespan of 18000 cycles (1200 h) is achieved. The numerical calculation illustrates that the distribution of zincate ions is more uniform in the presence of the flowing electrolyte, which is the key to the dendrite suppression. Thus, with the implementation of flowing electrolyte, a stable zinc electrode with an ultralong lifespan is demonstrated, which is promising for practical applications.