A MoS2/Carbon hybrid anode for high-performance Li-ion batteries at low temperature

Traditional lithium-ion batteries (LIBs) suffer from tremendous electrochemical performance fading at low temperatures (LT). This work reports a novel MoS2/C hybrid electrode that shows excellent LT performance as LIB anodes. At −20 °C, it delivers a stable discharge capacity as high as 854.3 mAh g−1 which is 72.8% of that at room temperature (RT). At a current density of 3 A g−1, a capacity of 140.9 mAh g−1 can still be achieved. The enlarged MoS2 interlayer spacing favors the fast Li+ diffusion, which in turn improves the lithiation/delithiation kinetics and the rate performance at LT. In-situ transmission electron microscopy (TEM) and galvanostatic intermittent titration technique (GITT) showed the fast Li+ diffusion kinetics at LT and the lithiation experiences a domain-by-domain reaction process, that is a multistep insertion-conversion reaction started from the outside domains to the neighboring inside domains, which is markedly different from that the two-step insertion-conversion process occurs at RT. Our results enrich the understanding of Li intercalation and diffusion kinetics of MoS2-based materials and provide a material design strategy for high-performance LIBs suitable for cold climate environment.