A room-temperature liquid eutectic GaSn anode with regulated wettability for lithium ion batteries

The alloy-type anodes in lithium ion batteries (LIBs) often suffer from the pulverization/failure of active materials caused by the drastic volume variations during cycling. Liquid Ga-based materials with low melting points and intrinsic self-healing feature are one of the best candidates for enhancing the Li storage property. Herein, a liquid eutectic GaSn (EGaSn) electrode was fabricated based upon a simple painting method and directly used as the anode for LIBs at room temperature. Furthermore, the wettability of liquid EGaSn alloy on the current collector in the Ar atmosphere was greatly improved through the construction of Ag3Ga modified layer on the stainless steel mesh (ssm) surface. And the Ag3Ga-EGaSn anode displays the much better Li storage performance (specific capacity, rate performance and cycling stability) than the untreated EGaSn anode. More importantly, operando XRD measurement clearly clarified the electrochemical reaction mechanism of Ag3Ga-EGaSn in LIBs. This work indicates a potential strategy to directly use liquid Ga-based electrode with regulated wettability for LIBs.