Hard carbons derived from pine nut shells as anode materials for Na-ion batteries

Guo Hao¹, Sun Kai^{1, †}, Lu Yaxiang^{2, 3, ‡}, Wang Hongliang¹, Ma Xiaobai¹, Li Zhengyao¹, Hu Yong-Sheng^{2, 3}, Chen Dongfeng^{1, §}

(a) Voltage profiles and (b) initial Columbic efficiencies of PNSHC-T electrodes at 0.1 C rate in the initial cycle.