A Room-Temperature Self-Healing Liquid Metal-Infilled Microcapsule Driven by Coaxial Flow Focusing for High-Performance Lithium-Ion Battery Anode

Liquid metals have attracted a lot of attention as self-healing materials in many fields. However, their applications in secondary batteries are challenged by electrode failure and side reactions due to the drastic volume changes during the "liquid-solid-liquid" transition. Herein, a simple encapsulated, mass-producible method is developed to prepare room-temperature liquid metal-infilled microcapsules (LMMs) with highly conductive carbon shells as anodes for lithium-ion batteries. Due to the reasonably designed voids in the microcapsule, the liquid metal particles (LMPs) can expand freely without damaging the electrode structure. The LMMs-based anodes exhibit superior capacity of rete-performance and ultra-long cycling stability remaining 413 mAh g-1 after 5000 cycles at 5.0 A g-1. Ex situ X-ray powder diffraction (XRD) patterns and electrochemical impedance spectroscopy (EIS) reveal that the LMMs anode displays a stable alloying/de-alloying mechanism. DFT calculations validate the electronic structure and stability of the room-temperature LMMs system. These findings will bring some new opportunities to develop high-performance battery systems.

A Temperature-Tolerant Magnesium-Ion Battery Using Ball Cactus-like MgV2O4 as High-Performance Cathode

Safe and high-performance secondary batteries using for all-climate conditions with different temperatures are highly required. Here, we develop a three-dimensional ball cactus-like MgV2O4 as cathode material for magnesium-ion (Mg-ion) batteries. After cycling 300 times, the capacity maintains 111.7 mAh g-1, while Coulombic efficiency stabilizes at about 100 %. Under temperatures of 45 °C and -5 °C, the capacities remain stable after 200 cycles. After three rounds of rate-performance tests, the capacity keeps quite stable. It is ascribed to the ball cactus-like morphology buffers the volumetric change during Mg2+ insertion/extraction, and provides sufficient pathways for ion diffusion, which has been verified by constant-current intermittent titration technology. It is believed that the good performance enables the Mg-ion batteries to have a all-climate capability.