Ultrafast and Durable Lithium Storage Enabled by Porous Bowl‐Like LiFePO4/C Composite with Na+ Doping

Abstract

AbstractPorous bowl‐like LiFePO4/C composites are prepared by using the ammonium salt and sodium salt processes with a facile precipitation method coupled with spray‐drying technology. Both of the as‐prepared LiFePO4/C composites present high crystallinity, bowl‐like morphology, and uniform carbon‐layer‐coated particles. Compared with the traditional ammonium salt process, the sodium salt process, without ammonia nitrogen pollutants, is not only environmentally friendly, but also allows us to introduce appropriate Na+ doping within the resultant LiFePO4. Moreover, the LiFePO4/C composite prepared by using the sodium salt process exhibits better electrochemical performance: a high rate capability (136, 129, and 119 mAh g−1 at 10, 20, and 40 C rate, respectively) and a long cycle stability (60.3 % of initial capacity after 3000 cycles at 10 C, only corresponding to 0.013 % capacity decay per cycle) compared with the other (only exhibits a capacity of 123, 107, and 62 mAh g−1 at rate of 10, 20, and 40 C and retains a 37.5 % of initial capacity after 3000 cycles at 10 C). This good electrochemical performance originates from its special morphology, high crystallinity, stable structure, and Na+ doping.