锂/钠离子电池用聚阴离子类柔性电极研究进展

Research progress on polyanion compounds flexible electrode of Li/Na-ion batteries

锂/钠离子电池用聚阴离子类柔性电极,由于具有较好的柔韧和延展性、高工作电位和框架型稳定结构等优势被广泛关注。根据所含过渡金属元素的种类将聚阴离子类柔性电极进行分类,从电极的制备方法和储能性能2个角度,对该类电极的发展历程和技术思路进行综述。在柔性电极制备方面,主要讨论了化学气相沉积法、静电纺丝法、溶剂热法和溶胶-凝胶法,讨论了不同方法对电极机械性能的影响。在储能性能方面,分析了比容量、工作电压、倍率性能和循环寿命4个指标,归纳了不同制备方法对储能性能的影响。对于高能量密度和长循环寿命的需求,指出了聚阴离子类柔性电极研发过程中存在能量密度不高、电化学性能优化不足和不统一的柔性评估标准等问题。

Polyanion compounds based flexible electrodes of Lithium/Sodium ion battery have shown many advantages,such as better flexibility,ductility,high working voltage,and stabilized framework structure,which attach extensive attention.Based on different types of transition metal elements in polyanion compounds,the developing process and technology idea of the electrode are reviewed from two views including electrode preparation method and energy storage performance of polyanion compounds.In terms of electrode preparation,the influence of electrospinning,solve thermal and sol-gel methods on the mechanical property of the electrode are mainly discussed.In the performance feature of energy storage,the impact on the properties of flexible batteries is assessed and analyzed from specific capacity,working voltage,rate performance to cycle life.Aiming at the requirement of high energy density and long cycle life in flexible electrode employing poly-anion type materials,the problems and developing direction of such materials,such as low energy density,optimization and matching of electrochemical performance and non-uniform evaluation criteria for the flexibility,are pointed out,and these will provide ideas for reference in the research and development of flexible electrode and battery devices with high performance in the future.