High-Performance Wide-pH Zn-Based Batteries via Electrode Interface Regulation with Valine Additive

Aqueous zinc (Zn) based batteries show great promise as energy storage devices, cost-effectiveness, and intrinsic safety. However, the development of Zn-based batteries faces significant challenges, primarily stemming from poor electrochemical reversibility caused by dendrite growth, hydrogen generation, and byproduct formation on the Zn anode. In this study, valine (Val) is investigated as an electrolyte additive to finely tune the interface microenvironment, resulting in enhanced electrochemical stability of the Zn anode across a wide pH range, marking the first time such an approach has been explored. Val ions preferably adsorb onto the active sites of the Zn anode surface, enabling efficient isolation of water and SO42- from the desolvated shell layer and thus effectively inhibiting dendrite growth. The Zn||Zn symmetric cells are demonstrated with Val electrolyte additives present a remarkable cycling performance of 5400 h. Furthermore, Zn||MnO2 full cells exhibit stable operation for 5000 cycles at 3 A g-1. Notably, the Val additive also functions effectively in rechargeable alkaline cells, enabling the alkaline symmetric cells and Zn||Ni0.8Co0.1Mn0.1O2 full cells to operate durably across a wide temperature range. This work offers unique insights into electrolyte engineering for aqueous rechargeable batteries, especially in terms of their compatibility with a wide pH range. This work proposes the microenvironment of znic (Zn) electrodes is improved by the presence of valine (Val) in both acidic and alkaline electrolytes conditions for the first time. The Val electrolyte additive greatly enhanced ultrahigh current density performance and cycling reversibility for Zn-based batteries within a wide-pH range and wide temperature workability.image