中文摘要：

高功率、高容量的LiNi0.8Co0.15Al0.05O2（NCA）正极锂离子电池在电动汽车和定置储能电池等行业中具有非常广阔的应用前景。为使其更具商业竞争力,NCA锂电池的使用寿命至少需要延长至15年,这对现行技术而言是一个很大的挑战。因此,明确NCA锂电池在循环和储存过程中性能衰减机理是延长NCA动力电池使用寿命的关键。大量研究表明正极表面膜的形成、表面盐岩结构类NiO相的出现、显微裂纹的产生、表面导电碳基体的恶化等因素是NCA动力电池衰减的主要原因。通过常规原子掺杂、表面包覆等方法在一定程度上能有效抑制正极材料的恶化,延长锂离子电池的使用寿命。

英文摘要：

LiNi0.8Co0.15Al0.05O2 lithium ion batteries have extremely broad application prospect in electric vehicles and stationary storage batteries due to its high capacity and high power. To be more economically attractive, it requires the batteries to have a long life during both storage and operation, typically more than 15 years. However, it still remains a challenge to achieve this goal, that is to say the short service life of LIB is a technological bottleneck for its application in electronic vehicles. Therefore, investigating the degradation mechanism of lithium-ion cell plays an important role in the achievement of long life for lithium-ion cell. Extensive research has shown that the formation of surface film, appearance of a NiO-like resistance layer with Fm3m rock structure, the micro-crack generation and deterioration of conductive carbon matrix are considered to be the dominant factors for the degradation of capacity and power. The deterioration of the cathode can be suppressed to a certain degree by the conventional modification methods, such as atomic doping, surface coating.