锂离子动力电池能量密度特性研究进展

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 2 000 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.