P2-type Na 2/3 Ni 1/3Mn 2/3O 2 Cathode Material with Excellent Rate and Cycling Performance for Sodium-Ion Batteries

P2-type Na 2/3 Ni 1/3Mn 2/3O 2 Cathode Material with Excellent Rate and Cycling Performance for Sodium-Ion Batteries

TitleP2-type Na 2/3 Ni 1/3Mn 2/3O 2 Cathode Material with Excellent Rate and Cycling Performance for Sodium-Ion Batteries
Publication TypeJournal Article
Year of Publication2019
AuthorsJing Mao, Xin Liu, Jianwen Liu, Heyang Jiang, Tao Zhang, Guosheng Shao, Guo Ai, Wenfeng Mao, Yan Feng, Wanli Yang, Gao Liu, Kehua Dai
JournalJournal of The Electrochemical Society
Volume166
Issue16
PaginationA3980 - A3986
Date Published12/2019
ISSN0013-4651
Abstract

P2-type Na2/3Ni1/3Mn2/3O2 is an air-stable cathode material for sodium-ion batteries. However, it suffers irreversible P2-O2 phase transition in 4.2-V plateau and shows poor cycling stability and rate capability within this plateau. To evaluate the practicability of this material in 2.3ā€“4.1 V voltage range, single-crystal micro-sized P2-type Na2/3Ni1/3Mn2/3O2 with high rate capability and cycling stability is synthesized via polyvinylpyrrolidone (PVP)-combustion method. The electrochemical performance is evaluated by galvanostatic charge-discharge tests. The kinetics of Na+ intercalation/deintercalation is studied detailly with potential intermittent titration technique (PITT), galvanostatic intermittent titration technique (GITT) and cyclic voltammetry (CV). The discharge capacity at 0.1 C in 2.3ā€“4.1 V is 87.6 mAh gāˆ’1. It can deliver 91.5% capacity at 40 C rate and keep 89% after 650 cycles at 5C. The calculated theoretical energy density of full cell with hard carbon anode is 210 Wh kgāˆ’1. The moderate energy density associated with high power density and long cycle life is acceptable for load adjustment of new-energy power, showing the prospect of practical application.

DOI10.1149/2.0211916jes
Short TitleJ. Electrochem. Soc.
Refereed DesignationRefereed