The Sabatier principle for Battery Anodes: Chemical Kinetics and Reversible Electrodeposition at Heterointerfaces

TL;DR

This paper demonstrates that optimal reversibility in battery anodes is achieved with moderate surface chemical interaction, applying a Sabatier-like principle to electrochemical interfaces for improved energy storage.

Contribution

It introduces a novel application of the Sabatier principle to battery anodes, revealing that moderate chemical interaction enhances reversibility and stability of metal plating/stripping.

Findings

Moderate surface interaction yields highest reversibility.

Strong interaction can hinder reversibility.

Design principles for earth-abundant metal anodes are proposed.

Abstract

How surface chemistry influences reactions occurring thereupon has been a long-standing question of broad scientific and technological interest for centuries. Recently, it has re-emerged as a critical question in a subdiscipline of chemistry - electrochemistry at heterointerphases, where the answers have implications for both how, and in what forms, humanity stores the rising quantities of renewable electric power generated from solar and wind installations world-wide. Here we consider the relation between the surface chemistry at such interphases and the reversibility of electrochemical transformations at a rechargeable battery electrode. Conventional wisdom holds that stronger chemical interaction between the metal deposits and electrode promotes reversibility. We report instead that a moderate strength of chemical interaction between the deposit and the substrate, neither too weak nor too strong, enables highest reversibility and stability of the plating/stripping redox processes at a battery anode. Analogous to the empirical Sabatier principle for chemical heterogeneous catalysis, our finding arises from the confluence of competing processes - one driven by electrochemistry and the other by chemical alloying. Based on experimental evaluation of metal plating/stripping systems in battery anodes of contemporary interest, we show that such knowledge provides a powerful tool for designing key materials in highly reversible electrochemical energy storage technologies based on earth-abundant, low-cost metals.