A High‐Performance Room‐Temperature Li||Ga–Sn Liquid Metal Battery for Grid Energy Storage

Abstract

Herein, a room‐temperature liquid metal battery (LMB) with a solid lithium anode electrode and gallium–tin (Ga–Sn) alloy cathode electrode is reported. With the improved wettability of the electric collector and grain‐refined liquid metal droplets cathode, the aforementioned LMB exhibits good cyclic reversibility and negligible self‐discharge. The result shows that the assembled Li||Ga–Sn battery has a satisfactory specific capacity (409 mAh g−1) and high energy efficiency (up to 92%). The low melting point Ga–Sn alloy can construct fast kinetics for the redox reaction and improve the electrode reaction kinetics, imparting the Li||Ga–Sn system with high discharge voltage (0.77 V at 1C) and smaller polarization voltage at different current densities, which ensure the high Coulomb efficiency and good rate performance of the battery. Moreover, the battery stably cycles at 35 °C for 60 cycles at the 1C rate, with no significant capacity degradation. With good electrochemical performance, simple structure, easy maintenance, and high safety, this room‐temperature Li||Ga–Sn battery may be a promising choice for power grid energy storage applications.

Amorphous TiO2 shells: an Essential Elastic Buffer Layer for High‐Performance Self‐Healing Eutectic GaSn Nano‐Droplet Room‐Temperature Liquid Metal Battery

“…In the Ga 3d spectrum, the peak around 17.9 eV is Ga 0 . In addition, the peak of Ga−O (20.3 eV) indicates the partial oxidation of eGaSn during the preparation process [16] . Furthermore, the X‐ray diffraction (XRD) patterns demonstrated that the prepared eGaSn NDs are amorphous (Figure 2i).…”

“…In addition, the peak of GaÀ O (20.3 eV) indicates the partial oxidation of eGaSn during the preparation process. [16] Furthermore, the X-ray diffraction (XRD) patterns demonstrated that the prepared eGaSn NDs are amorphous (Figure 2i). The FE-SEM image of eGaSn@TiO 2 (Figures 2c, S5) shows favourable dispersion and sphericity, because of the coating of eGaSn NDs with an approximately 6.5 nm-thickness amorphous TiO 2 layer (Figures 2d, e, S6).…”

“…The authors have cited additional references within the Supporting Information (Ref. [13,16,18,19,33]).…”

“…Liu et al [15] used a GaIn alloy with a low melting point as the negative electrode for a liquid metal battery to demonstrate good electrochemical performance. Wang et al [16] used eGaSn microdroplets as negative electrodes to increase the battery life. Wei et al [17] confined 3 °C GaInSnZn liquid metal in the matrix of MXene paper without any binder or conductive additive to fabricate a lightweight, flexible, and freestanding MXene/liquid metal paper.…”

“…used a GaIn alloy with a low melting point as the negative electrode for a liquid metal battery to demonstrate good electrochemical performance. Wang et al [16] . used eGaSn microdroplets as negative electrodes to increase the battery life.…”