High‐Rate and Long Cycle‐Life Alloy‐Type Magnesium‐Ion Battery Anode Enabled Through (De)magnesiation‐Induced Near‐Room‐Temperature Solid–Liquid Phase Transformation
High‐Rate and Long Cycle‐Life Alloy‐Type Magnesium‐Ion Battery Anode Enabled Through (De)magnesiation‐Induced Near‐Room‐Temperature Solid–Liquid Phase Transformation
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DOI：
10.1002/aenm.201902086
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发表时间：
2019-10
影响因子：
27.8
通讯作者：
Lin Wang;Samuel S. Welborn;H. Kumar;Manni Li;Zeyu Wang;V. Shenoy;E. Detsi
中科院分区：
文献类型：
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作者：
Lin Wang;Samuel S. Welborn;H. Kumar;Manni Li;Zeyu Wang;V. Shenoy;E. Detsi
锂离子电池中使用的资源由于其高需求而变得越来越昂贵，全球钴市场严重依赖地缘政治风险高的国家的供应。因此，需要包括镁离子电池的替代电池技术。实用镁离子电池的进展受到可以与常规电解质溶剂一起工作的合适阳极的缺乏的阻碍。虽然合金型镁离子电池阳极与常见的电解质溶剂兼容，但它们在循环过程中会发生与巨大体积变化相关的严重故障。因此，在合金型镁离子电池阳极中实现超过200次循环仍然是一个挑战。在此，利用Mg 2Ga 5（固体）和Ga（液体）之间的近室温固-液相转变，在Mg 2Ga 5合金型阳极中以相对较高的3 C（电流密度：922.5 mA g−1）（放电）速率实现了前所未有的1000次循环的长循环寿命。这一概念将为下一代镁离子电池的实用阳极开发开辟道路。
Resources used in lithium‐ion batteries are becoming more expensive due to their high demand, and the global cobalt market heavily depends on supplies from countries with high geopolitical risks. Alternative battery technologies including magnesium‐ion batteries are therefore desirable. Progress toward practical magnesium‐ion batteries are impeded by an absence of suitable anodes that can operate with conventional electrolyte solvents. Although alloy‐type magnesium‐ion battery anodes are compatible with common electrolyte solvents, they suffer from severe failure associated with huge volume changes during cycling. Consequently, achieving more than 200 cycles in alloy‐type magnesium‐ion battery anodes remains a challenge. Here an unprecedented long‐cycle life of 1000 cycles, achieved at a relatively high (dis)charge rate of 3 C (current density: 922.5 mA g−1) in Mg2Ga5 alloy‐type anode, taking advantage of near‐room‐temperatures solid–liquid phase transformation between Mg2Ga5 (solid) and Ga (liquid), is demonstrated. This concept should open the way to the development of practical anodes for next‐generation magnesium‐ion batteries.