关键词: 锂离子电池, 液态金属, 负极, 电化学性能, 自愈合效应

Abstract:

To harness the excellent fluidity and self-healing characteristics of liquid metal, two novel electrodes, liquid metal nanoparticles (LMNP) and liquid metal film (LMF), were fabricated via probe ultrasonication and doctor-blading methods, respectively. The microstructural features, mechanical properties, and electrochemical performances of these electrodes were comprehensively investigated using focused ion beam milling, scanning electron microscopy, nanoindentation, and electrochemical measurements. The LMNP electrode exhibited a uniform dispersion of nanoparticles within the matrix, forming strong interparticle connections, whereas the LMF electrode formed a continuous film on the substrate, which developed cracks at the interface with the current collector. The LMNP electrode demonstrated superior rate capability and cycling stability compared to the LMF electrode. After 300 cycles at a current density of 2.0 A/g, the LMNP electrode maintained a reversible specific capacity of 399.3 mAh/g with a capacity retention of 86.9%. During cycling, both electrodes underwent particle size reduction and self-healing-induced welding, providing additional conductive pathways that facilitated charge transfer. Moreover, both electrodes exhibited a gradual transition from a soft to a rigid structure during cycling; however, the LMNP electrode achieved this transition more rapidly, resulting in earlier structural stabilization and enhanced electrochemical performance. These findings provide critical insights into the application of liquid metal-based electrodes and offer valuable guidance for designing high-performance anode materials for lithium-ion batteries.

Key words: lithium-ion battery, liquid metal, anode, electrochemical performance, self-healing effect