Wang Yiting, Li Yifei, Chai Jiali, Rui Yichuan, Jiang Lei, Tang Bohejin
College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, PR China.
Department of Chemical Engineering, KU Leuven, Leuven 3001, Belgium.
Dalton Trans. 2024 May 28;53(21):9081-9091. doi: 10.1039/d4dt00696h.
Lithium-ion batteries (LIBs) are greatly limited in their practical application because of their poor cycle performance, low conductivity and volume expansion. Herein, molten salts (MSs) FeCl·6HO-NMP with low temperature simple preparation are used as the anode material of LIBs for the first time to break through the bottleneck of LIBs. The good fluidity and high self-healing of FeCl·6HO-NMP effectively avoid the collapse and breakage of the structure. Based on this feature, the initial discharge specific capacity reached 770.28 mA h g, which was more than twice that of the commercial graphite anode. After 200 cycles at a current density of 100 mA g, the specific capacity did not decrease rather it was found to be higher than the initial discharge specific capacity, reaching 867.24 mA h g. Besides, the good conductivity of MSs provides convenience for the removal and intercalation of Li. The active H sites that can combine with lithium ions form LiH and provide capacity for LIBs. Density functional theory (DFT) calculation also provided theoretical proof for the mechanism of LIBs.
锂离子电池（LIBs）由于其循环性能差、导电性低和体积膨胀等问题，在实际应用中受到极大限制。在此，首次将低温简单制备的熔盐（MSs）FeCl·6H₂O-NMP用作LIBs的负极材料，以突破LIBs的瓶颈。FeCl·6H₂O-NMP良好的流动性和高自修复性有效避免了结构的坍塌和破裂。基于这一特性，初始放电比容量达到770.28 mA h g，是商用石墨负极的两倍多。在100 mA g的电流密度下循环200次后，比容量没有下降，反而发现高于初始放电比容量，达到867.24 mA h g。此外，MSs良好的导电性为Li的脱出和嵌入提供了便利。能够与锂离子结合形成LiH的活性H位点为LIBs提供了容量。密度泛函理论（DFT）计算也为LIBs的机理提供了理论依据。
