Scalable porous zinc anode to improve the cycling performance of aqueous lithium energy storage systems

Abstract

Abstract A porous zinc anode is successfully fabricated using a simple, scalable method for use in Rechargeable Hybrid Aqueous Battery (ReHAB) systems. The porous anode provides a higher surface area (2X), roughness, and wettability than the planar one. These properties allow for better contact between the anode surface and the electrolyte, increasing the cycling performance when used in the ReHAB system. ReHABs with the porous anode show an improvement in initial discharge capacity (34%) at 1C, capacity retention after 300 cycles at 1C, rate performance at various C-rates, and float charge current (a 94% decrease). This decrease in float charge current corresponds to the lower levels of gas generated from detrimental side reactions during battery operation. The enhancements in the rate performance as well as minimized gas evolution in both small (1.13 cm2 in 1.15 mAh coin-cell) and large (9 cm2 in 7 mAh big battery) show the promising potential of the porous anode for use in large-scale battery applications. Based on the findings from various characterization techniques, suppression in dendrite growth and side reactions on the porous anode surface during battery operations have been the main reason for the improvement in ReHAB cycling performance.