Design of an ultra-durable silicon-based battery anode material with exceptional high-temperature cycling stability

Abstract

Nanostructured silicon is a promising candidate material for practical use in energy storage devices. However, high temperature operation remains a significant challenge because of severe electrochemical side reactions. Here, we show the design of ultra-durable silicon made by introducing dual coating layers on the silicon surface, allowing stable operation at high temperature. The double layers, which consist of amorphous metal titanate and carbon, provide several advantages including: (i) suppression of volume expansion during Li+ insertion; (ii) creation of a stable solid-electrolyte-interface layer; and (iii) preservation of original Si morphology over 600 cycles at high temperature. The resulting silicon-based anode exhibits a reversible capacity of 990 mA h g-1 after 500 cycles at 25 °C and 1300 mA h g-1 after 600 cycles at 60 °C with a rate of 1 C.