Precycling Strategy in Suitable Voltage to Improve the Stability of Interfacial Film and Suppress the Decline of LiNi0.6Mn0.2Co0.2O2 Cathode at Elevated Temperatures

Shiyou Li; Kerong Yang; Yin Quan; Hui Wang; Ling Hu; Baoqiang Li; Dongni Zhao

doi:10.1021/acsami.4c03939

Precycling Strategy in Suitable Voltage to Improve the Stability of Interfacial Film and Suppress the Decline of LiNi_0.6Mn_0.2Co_0.2O₂ Cathode at Elevated Temperatures

ACS Appl Mater Interfaces. 2024 May 22;16(20):26245-26256. doi: 10.1021/acsami.4c03939. Epub 2024 May 13.

Authors

Shiyou Li^{1

2

3}, Kerong Yang^{1

2}, Yin Quan^{1

2}, Hui Wang^{1

2}, Ling Hu^{1

2}, Baoqiang Li^{1

2}, Dongni Zhao^{1

2

3}

Affiliations

¹ School of Petrochemical Technology, Lanzhou University of Technology, Lanzhou 730050, P. R. China.
² Key Laboratory of Low Carbon Energy and Chemical Engineering of Gansu Province, Lanzhou 730050, P. R. China.
³ Gansu Engineering Laboratory of Electrolyte Material for Lithium-Ion Battery, Baiyin 730900, P. R. China.

PMID: 38739838
DOI: 10.1021/acsami.4c03939

Abstract

Layered ternary oxide LiNi_xMn_yCo_1-x-yO₂ is a promising cathode candidate for high-energy lithium-ion batteries (LIBs). However, the capacity of LIBs is significantly restricted by several factors, including the repeated dissolution-regeneration of the interfacial film at high temperatures, the dissolution of transition metals, and the increase of impedance. Herein, a new precycling strategy in suitable voltage scope at room temperature is proposed to construct a uniform, thermally stable, and insoluble cathode-electrolyte interface (CEI), which helps to maintain stable cycling performances at high temperatures. Specifically, after 5 precycles in the range of 3.85-4.3 V at room temperature, a CEI layer containing numerous inorganic components and oligomers is formed on the surface of LiNi_0.6Mn_0.2Co_0.2O₂. Subsequently, the harmful side reactions are effectively suppressed, endowing the cell with an excellent capacity retention of 84.67% after 50 cycles at 0.5C and 55 °C, much higher than that of 65.61% under the conventional film-forming process conditions. This work emphasizes the crucial role of the precycling strategy in regulating the characteristics of CEI layer on the surface of cathode electrode, opening up a new avenue for the high-temperature application of positive electrodes of LIBs.

Keywords: LiNi0.6Mn0.2Co0.2O2; cathode-electrolyte interface; high-temperature performance; inorganic components; lithium-ion battery; precycling strategy.