Cu/Co binary‐transition metal glycerolates as anode materials for lithium‐ion batteries

Abstract The energy density of Lithium‐ion batteries (LiBs) fails to keep pace with the growing demand for long‐driving range EVs. Developing novel anode materials with high specific capacities is one of the most effective ways to increase the energy density of LiBs. Herein, a series of Cu and Co binary‐transition metal glycerolates (labeled as Cu x Co y /G) were prepared as the anodes for LiBs. It was observed that Cu x Co y /G exhibited a distinctive yolk‐shell architecture, which significantly differed from the solid spherical structure of Cu/G and Co/G counterparts. X‐ray powder diffraction and Scanning electron microscope studies suggested that Cu element existed as Cu 2+1 O in Cu x Co y /G, and the Co element was in the form of amorphous glycerolates. Electrochemical studies showed that Cu 0.4 Co 1 /G delivered a high capacity over 1000 mAh g −1 at the first discharge, and it exhibited the most stable cycling performance over 200 cycles. Mechanism study suggested both Cu and Co elements contributed to lithium storage capacities in Cu x Co y /G at the initial discharging process. Experimental results revealed that Co exhibited reversible capacity while Cu element was reduced to metallic Cu which contributed to the electronic conductivity, rendering Cu 0.4 Co 1 /G exhibited a better long‐term cycling stability than Co/G. This work explored a new type of anode material with high specific capacity for LiBs, paving the way to high energy density LiBs.