锂离子动力电池能量密度特性研究进展

Research Progress on Energy Density of Li-ion Batteries for Evs

动力电池作为新能源纯电动汽车的动力源,其能量密度与整车的续驶里程及安全性等密切相关,而锂离子电池具有高能量密度和长寿命等特点,是当前新能源汽车动力电池的主流选择。基于锂离子电池发展史和我国第1~48批《免征车辆购置税的新能源汽车车型目录》中2000余款纯电动乘用车的锂离子动力电池能量密度数据,系统研究了锂离子动力电池能量密度演变趋势,回顾了我国锂离子动力电池能量密度的提升历程及其对推动新能源汽车发展起到的良好作用。在此基础上,从电极材料、电池工艺和成组结构等3个方面,剖析了锂离子动力电池能量密度提升技术方案的优势与不足;并从电池能量密度和安全性的关联性出发,总结了高能量密度电池在设计、制造和使用等全生命周期中的安全技术,展望了锂离子动力电池未来的发展趋势,为新能源汽车行业未来的健康发展提供参考。

The power battery is the source of driving energy for electric vehicles(EVs),which is directly related to driving range and the safety of EVs.So far,lithium-ion batteries(LIBs)have been extensively used as the power sources for EVs owing to the high energy density and long cycle-life.Based on the battery history and the LIB energy density data of more than 2000 types of passenger EVs in the 1-48 Catalogs of new energy vehicles exempted from vehicle purchase tax of China,the evolution process of the LIB energy density increasing is systematically analyzed from the data in the Catalog.Meanwhile,the improvement of LIB energy density in China and its role in promoting the development of EVs are reviewed.Then,the advantages and disadvantages of the energy density enhancement technology for lithium-ion power battery are analyzed from the aspects of electrode material,battery process engineering and battery pack structure.Finally,based on the correlation between battery energy density and safety,the safety technologies of high energy density battery in design phase,manufacture phase and use phase of the whole cycle life are summarized,and the development trend of lithium-ion power battery is prospected,which can provide a reference for the healthy development of EVs.