%0 Journal Article
%A Jing Mao
%A Xin Liu
%A Jianwen Liu
%A Heyang Jiang
%A Tao Zhang
%A Guosheng Shao
%A Guo Ai
%A Wenfeng Mao
%A Yan Feng
%A Wanli Yang
%A Gao Liu
%A Kehua Dai
%B Journal of The Electrochemical Society
%D 2019
%G eng
%N 16
%P A3980 - A3986
%R 10.1149/2.0211916jes
%T P2-type Na <sub>2/3</sub> Ni <sub>1/3</sub>Mn <sub>2/3</sub>O <sub>2</sub> Cathode Material with Excellent Rate and Cycling Performance for Sodium-Ion Batteries
%V 166
%8 12/2019
%! J. Electrochem. Soc.
%X <p><span>P2-type Na</span><span>2/3</span><span>Ni</span><span>1/3</span><span>Mn</span><span>2/3</span><span>O</span><span>2</span><span>&nbsp;is an air-stable cathode material for sodium-ion batteries. However, it suffers irreversible P2-O2&nbsp;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 2.3–4.1&nbsp;V voltage range, single-crystal micro-sized P2-type Na</span><span>2/3</span><span>Ni</span><span>1/3</span><span>Mn</span><span>2/3</span><span>O</span><span>2</span><span>&nbsp;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</span><span>+</span><span>&nbsp;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 2.3–4.1&nbsp;V is 87.6&nbsp;mAh g</span><span>−1</span><span>. 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&nbsp;Wh kg</span><span>−1</span><span>. 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.</span></p>