Stabilizing the Electrode/Electrolyte Interface of LiNi0.8Co0.15Al0.05O2 through Tailoring Aluminum Distribution in Microspheres as Long-Life, High-Rate, and Safe Cathode for Lithium-Ion Batteries

• DOI: 10.1021/acsami.7b05986
• Publication Date: 2017-08-07T12:54:39Z
• Authors: Peiyu Hou; Hongzhou Zhang; Xiaolong Deng; Xijin Xu; Lianqi Zhang
• Keywords: Coprecipitation; Thermal Stability; Oxidizing agent

The unstable electrode/electrolyte interface of high-capacity LiNi0.8Co0.15Al0.05O2 (NCA) cathodes, especially at a highly delithiated state, usually leads to the transformation layered spinel and/or rock-salt phases, resulting in drastic capacity fade and poor thermal stability. Herein, Al-increased Ni-,Co-decreased electrode surface is fabricated through tailoring element distribution micrometer-sized spherical NCA secondary particles via coprecipitation solid-state reactions, aimed stabilizing during continuous cycles. As expected, it shows much extended cycle life, 93.6% retention within 100 cycles, compared with that 78.5% for normal NCA. It also delivers large reversible about 140 mAh g–1 even 20 C, corresponding energy density around 480 Wh kg–1, which enhanced by 45% (about 330 kg–1). Besides, delayed heat emission temperature reduced generation mean remarkably improved These foregoing improvements are ascribed particle stabilizes protecting inner components from directly contacting electrolyte suppressing side reaction on between high oxidizing Ni4+ electrolyte.