An Innovative Lithium Ion Battery System Based on a Cu<sub>2</sub>S Anode Material
Yunhui Wang, Xinran Feng, Yin Xiong, Stanislav Stoupin, Rong Huang, Min Zhao, Mingsheng Xu, Peng Zhang, Jinbao Zhao, Héctor D. Abruña
Abstract
Cu2S is considered as one of the potential anode paradigms for advanced rechargeable batteries because of its high theoretical capacity (∼335 mAh·g–1), high and flat charge/discharge voltage plateaus (∼1.7 V vs Li+/Li), stable cycling performance, and its elemental abundance. However, many studies have shown that Cu2S exhibits a dramatic capacity fade in carbonate-based electrolytes, which has precluded its commercialization when paired with high voltage cathodes in state-of-the-art lithium ion batteries. Here, we report on a fundamental mechanistic study of the electrochemical processes of Cu2S in both ether- and carbonate-based electrolytes employing operando synchrotron X-ray methods. Based on our findings, we developed a Cu2S/C composite material that suppresses its failure mechanism in carbonate-based electrolytes and further demonstrated its feasibility in lithium ion full cells for the first time. Our experiment provides the basis for the utilization of Cu2S in industrial-scale applications for large-scale electrical energy storage.