An Ultra‐Long‐Life Lithium‐Rich Li1.2Mn0.6Ni0.2O2 Cathode by Three‐in‐One Surface Modification for Lithium‐Ion Batteries. (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. Volume 132:Number 20(2020)
• Page Start: 7852
• Page End: 7856
• Publication Date: 2020-03-03
• Subjects: Schichtoxide -- N-dotierte Kohlenstoffnanoschichten -- Sauerstoffleerstellen -- Spinell-Phase -- Spannungsabfall; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202000628
• Languages: English
• ISSNs: 0044-8249

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 : Eine dreifache Oberflächenmodifikation wird vorgestellt. Sie besteht aus Sauerstoffleerstellen, Spinellphasenintegration und N‐dotierten Kohlenstoffnanoschichten, die synchron auf der Oberfläche von Li1.2 Mn0.6 Ni0.2 O2 ‐Mikrokugeln durch Pyrolyse von Harnstoff aufgebaut werden. Die Spannungs‐ und Kapazitätsstabilität wird durch diese Methode verbessert.