Abstract In this paper, a series of hard carbon was firstly fluorinated via gas-phase fluorination and their electrochemical performances were adjusted by varying fluorination temperature. It is found that the F/C ratios of fluorinated hard carbon increased with rising temperature consecutively, whereas the discharge plateau decreased due to the lowered content of semi-ionic C–F bond. The fluorinated hard carbon obtained at 390 °C approximately exhibited the highest specific capacity of 922.6 mAh g-1 with the discharge potential of 2.7 V (vs. Li/Li+), which delivered the energy density of 2466 Wh kg-1, higher than the theoretical value (2180 Wh kg-1) of commercial fluorinated graphite. In addition, the sample obtained at about 370 °C delivered good rate capability that the capacity retention ratio was 74.3% even at current density of 5C. Hard carbon, as one of widely applied anode materials in sodium ion batteries, was firstly fluorinated in this study, and the superior electrochemical performances than fluorinated graphite as well as its low cost and scalable product demonstrated its great potential practicability in the field of lithium primary batteries to replace the commercial fluorinated graphite in the market.

中文翻译：

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氟化硬碳作为锂原电池正极的电化学性能

摘要 本文首先采用气相氟化法对一系列硬碳进行氟化，并通过改变氟化温度来调节其电化学性能。发现氟化硬碳的 F/C 比随着温度的升高连续增加，而放电平台由于半离子 C-F 键含量的降低而降低。在 390 °C 下获得的氟化硬碳大约表现出最高的比容量 922.6 mAh g-1，放电电位为 2.7 V（vs. Li/Li+），其能量密度为 2466 Wh kg-1，高于商业氟化石墨的理论值（2180 Wh kg-1）。此外，在约 370°C 下获得的样品具有良好的倍率性能，即使在 5C 的电流密度下容量保持率为 74.3%。