【摘要】 随着移动通讯设备和电动汽车的发展,对高比能量密度锂离子电池的需求越来越大。目前商业化动力电池主要采用的磷酸铁锂和三元正极材料放电比容量均低于180 mAh/g,难以满足一次充电行驶500公里以上的要求,因此,正极材料的比容量已成为限制锂离子电池能量密度提高的瓶颈。富锂材料具有大的比容量(≥250 mAh/g)和高的放电电压(3.8 V),理论能量密度高达900 Wh/kg,是未来动力电池的理想正极材料,因而研究高比容量富锂正极材料具有非常重要的现实意义。本文回顾了锂离子电池正极材料的发展和目前商业化正极材料比容量低的现状,综述了新一代大比容量富锂正极材料的结构特征和电化学性质,以及放电机制和改性研究的最新进展,并指出现阶段高能量密度锂离子电池用富锂材料遇到的问题,且有针对性地提出了解决思路和方法。更多还原

【Abstract】 With the development of mobile communication equipment and electric cars,there is an increasing demand for high capacity lithium-ion batteries. It is difficult for the present commercialized lithium-ion pow er batteries to meet the requirement of one charge to travel above 500 km,because of low discharge capacity,like lithium iron phosphate and ternary cathode material,possessing the discharge capacity low er than 180 mAh/g.Therefore,the specific capacity of cathode materials has become a bottleneck to increase the energy density of lithium-ion batteries. Lithium-rich cathode materials w ith large specific capacity( ≥ 250 mAh/g), high discharge voltage( 3. 8 V),and high theory energy density( 900 Wh/kg) are thought as ideal cathode material of pow er batteries for electric cars in the future,so,it is of great realistic significance to study the lithium-rich cathode materials w ith high specific capacity. This paper review s the development of cathode materials for lithium-ion batteries as w ell as the situation of recent commercial cathode materials w ith low specific capacity.Structures and electrochemical properties of lithium-rich cathode materials as a new next-generation higher capacity are summarized,and the discharge mechanism and the latest progress in modifications are presented.M oreover,some problems related w ith lithium-rich materials for high energy-density lithium-ion batteries are presented,follow ed by the corresponding ideas and approaches of solution.更多还原