Improved electrochemical performances of high voltage LiCoO<sub>2</sub> with tungsten doping<xref rid="cpb_27_8_088202_fn1" ref-type="fn">*</xref><fn id="cpb_27_8_088202_fn1"><label>*</label><p>Project supported by the National Key Rerearch and Development Program of China (Grant No. 2017YFB0102004), the National Natural Science Foundation of China (Grant No. 51502334), the Fund from Beijing Municipal Science & Technology Commission, China (Grant No. D171100005517001), and the Thousand Talent Program for Outstanding Young Scientists, China.</p></fn>

Improved electrochemical performances of high voltage LiCoO₂ with tungsten doping**

Project supported by the National Key Rerearch and Development Program of China (Grant No. 2017YFB0102004), the National Natural Science Foundation of China (Grant No. 51502334), the Fund from Beijing Municipal Science & Technology Commission, China (Grant No. D171100005517001), and the Thousand Talent Program for Outstanding Young Scientists, China.

Zhang Jie-Nan^{1, 2}, Li Qing-Hao¹, Li Quan^{1, 2}, Yu Xi-Qian^{1, †}, Li Hong^{1, 2, ‡}

(color online) The electrochemical impedance spectra of LiCoO₂/Li battery measured after (a) 1st cycle and (b) 50th cycle. The spectra were collected at 25 °C between 1 MHz and 1 mHz.