ZnO‐Embedded Expanded Graphite Composite Anodes with Controlled Charge Storage Mechanism Enabling Operation of Lithium‐Ion Batteries at Ultra‐Low Temperatures

Abstract

As lithium (Li)‐ion batteries expand their applications, operating over a wide temperature range becomes increasingly important. However, the low‐temperature performance of conventional graphite anodes is severely hampered by the poor diffusion kinetics of Li ions (Li+). Here, zinc oxide (ZnO) nanoparticles are incorporated into the expanded graphite to improve Li+ diffusion kinetics, resulting in a significant improvement in low‐temperature performance. The ZnO–embedded expanded graphite anodes are investigated with different amounts of ZnO to establish the structure‐charge storage mechanism‐performance relationship with a focus on low‐temperature applications. Electrochemical analysis reveals that the ZnO–embedded expanded graphite anode with nano‐sized ZnO maintains a large portion of the diffusion‐controlled charge storage mechanism at an ultra‐low temperature of −50 °C. Due to this significantly enhanced Li+ diffusion rate, a full cell with the ZnO–embedded expanded graphite anode and a LiNi0.88Co0.09Al0.03O2 cathode delivers high capacities of 176 mAh g−1 at 20 °C and 86 mAh g−1 at −50 °C at a high rate of 1 C. The outstanding low‐temperature performance of the composite anode by improving the Li+ diffusion kinetics provides important scientific insights into the fundamental design principles of anodes for low‐temperature Li‐ion battery operation.

Porous High-Entropy Oxide Anode Materials for Li-Ion Batteries: Preparation, Characterization, and Applications

“…The growth of the electric vehicle industry poses a vast challenge to lithium-ion batteries. However, commercially available graphite anodes are no longer able to meet the needs of the electric vehicle industry [82,83]. Among the many materials explored for high-performance anodes, transition metal oxides have received considerable attention due to their high theoretical capacity, low cost, and easy preparation, but the vast volume expansion during cycling and their inherent semiconducting nature limit their application [84][85][86].…”