Dual-Function Presodiation with Sodium Diphenyl Ketone towards Ultra-stable Hard Carbon Anodes for Sodium-Ion Batteries
Dual-Function Presodiation with Sodium Diphenyl Ketone towards Ultra-stable Hard Carbon Anodes for Sodium-Ion Batteries
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DOI：
10.1002/anie.202214717
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发表时间：
2022-12-02
影响因子：
16.6
通讯作者：
Li, Fujun
中科院分区：
文献类型：
--
作者：
Fang, Hengyi;Gao, Suning;Li, Fujun
硬碳（HC）是一种很有前途的钠离子电池负极材料，但仍存在初始库仑效率（ICE）低和固体电解质界面（SEI）不稳定的问题。本文采用二苯甲酮钠（Na-DK）实现HC阳极的双功能预辐射。它补偿了含氧官能团的不可逆Na吸收，并与HC中准金属钠的五/七元环的碳缺陷反应。所形成的钠在二甘醇二甲醚中的1.0 M NaPF 6中诱导HC上的稳健的富含NaF的SEI，有利于界面反应动力学和稳定的Na+插入和提取。这使得预掺杂HC（pHC）具有接近100%的高ICE和6800次循环后82.4%的容量保持率。经证明，其与全电池中的Na 3V 2（PO 4）（3）阴极偶联，在700次循环后显示出接近100%的高容量保持率。这项工作提供了对化学预辐射的深入理解和高稳定性钠离子电池的新策略。
Hard carbon (HC) is a promising anode material for sodium-ion batteries, yet still suffers from low initial Coulombic efficiency (ICE) and unstable solid electrolyte interphase (SEI). Herein, sodium diphenyl ketone (Na-DK) is applied to realize dual-function presodiation for HC anodes. It compensates the irreversible Na uptake at the oxygen-containing functional groups and reacts with carbon defects of five/seven-membered rings for quasi-metallic sodium in HC. The as-formed sodium induces robust NaF-rich SEI on HC in 1.0 M NaPF6 in diglyme, favoring the interfacial reaction kinetics and stable Na+ insertion and extraction. This renders the presodiated HC (pHC) with high ICE of approximate to 100 % and capacity retention of 82.4 % after 6800 cycles. It is demonstrated to couple with Na3V2(PO4)(3) cathodes in full cells to show high capacity retention of approximate to 100 % after 700 cycles. This work provides in-depth understanding of chemical presodiation and a new strategy for highly stable sodium-ion batteries.