An Ultra‐Long‐Life Lithium‐Rich Li1.2Mn0.6Ni0.2O2 Cathode by Three‐in‐One Surface Modification for Lithium‐Ion Batteries. Issue 20 (3rd March 2020)

• Record Type: Journal Article
• Authors: Ding, Xiaokai; Luo, Dong; Cui, Jiaxiang; Xie, Huixian; Ren, Qingqing; Lin, Zhan
• Is Part Of: Angewandte Chemie international edition. Volume 59:Issue 20(2020)
• Page Start: 7778
• Page End: 7782
• Publication Date: 2020-03-03
• Subjects: layered oxides -- N-doped carbon nanolayers -- oxygen vacancies -- spinel phase -- voltage decay; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.202000628
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Voltage decay and capacity fading are the main challenges for the commercialization of Li‐rich Mn‐based layered oxides (LLOs). Now, a three‐in‐one surface treatment is designed via the pyrolysis of urea to improve the voltage and capacity stability of Li1.2 Mn0.6 Ni0.2 O2 (LMNO), by which oxygen vacancies, spinel phase integration, and N‐doped carbon nanolayers are synchronously built on the surface of LMNO microspheres. Oxygen vacancies and spinel phase integration suppress irreversible O2 release and help lithium ion diffusion, while N‐doped carbon nanolayer mitigates the corrosion of electrolyte with excellent conductivity. The electrochemical performance of LMNO after the treatment improves significantly; the capacity retention rate after 500 cycles at 1 C is still as high as 89.9 % with a very small voltage fading rate of 1.09 mV cycle −1 . This three‐in‐one surface treatment strategy can suppress the voltage decay and capacity fading of LLOs. Abstract : A three‐in‐one surface modification is presented. It consists of oxygen vacancies, spinel phase integration, and N‐doped carbon nanolayers synchronously built on the surface of Li1.2 Mn0.6 Ni0.2 O2 microspheres via the pyrolysis of urea. Voltage and capacity stability are improved by this method.