Constructing protective layer on electrode for ultra-enduring Zn ions batteries

Owing to the virtues of intrinsic safety, high theoretical capacity, rechargeable aqueous Zn ions batteries based on cobalt hexacyanoferrate (Co-HCF) cathode and Zn anode have sparked a lot of enthusiasm in the energy storage field recently. However, the issues of Zn anode (such as dendrites formation and sustained hydrogen evolution) and pulverization of Co-HCF cathode seriously restrict the practical application of Zn ions batteries. In this work, a protective layer coated on Zn anode to improve the stability of Zn anode and ensure uniform Zn deposition as well as a polymer layer coated on Co-HCF cathode to sustain the structural stability of Co-HCF. Benefiting from the merits of the protective layer both on the cathode and anode, the obtained Zn ions batte-ries provide a specific capacity (76.9 mAhg-1 at 0.1 Ag-1), outstanding rate capability (50.1 mAhg-1at 1 Ag-1), and outstanding cyclic stability (-91.9 % after 1000 cycles at 1 Ag-1) compared to that of the traditional Zn// Co-HCF (-62.5 %). Thus, this present work supplies a new way to construct high-performance Zn ions batteries with long cyclic life for practical applications.

Automated summary

Recently, rechargeable aqueous Zn ions batteries based on Co-HCF cathode and Zn anode have gained much attention for their intrinsic safety and high theoretical capacity. However, issues with Zn anode and Co-HCF cathode have limited the practical application of Zn ions batteries. In this study, a protective layer was coated on the Zn anode to improve its stability and ensure uniform Zn deposition, while a polymer layer was coated on the Co-HCF cathode to sustain its structural stability. The resulting Zn ions batteries exhibited high performance and long cyclic life.