Geng Jing, Zou Zhengguang, Wang Tianxing, Zhang Shuchao, Ling Wenqin, Peng Xiaoxiao, Liang Fangan
College of Materials Science and Engineering, Guilin University of Technology, Guilin, 541004, People's Republic of China.
Collaborative Innovation Center for Exploration of Hidden Nonferrous Metal Deposits and Development of New Materials, Guilin University of Technology, Guilin, 541004, People's Republic of China.
Nanotechnology. 2023 Aug 18;34(44). doi: 10.1088/1361-6528/acec55.
In an era of rapid industrial development, such that the demand for energy is increasing daily, lithium-ion batteries are playing a dominant role in energy storage devices due to their high safety and low cost. However, it is still a challenge for the preparation of advanced cathodes, which can determine the battery performance, with stable structures and fast diffusion of Li. This is especially the case for lithium iron phosphate (LFP), a cathode material with severe limitations due to its low conductive efficiency. To improve its conductivity, LFP was compounded with defect-modified VOto prepare LFP/V/C materials with excellent electrochemical properties, which exhibited an initial capacity of 138.85 mAh gand 95% retention after 500 charge/discharge cycles at a current density of 5 C. Also, the effect of defects on ionic diffusion was discussed in detail by means of density function theor (DFT) calculations, confirming that the improvement of electrochemical performance is closely related to the introduction of hybrid conductive layers of surface cladding.
在工业快速发展的时代,能源需求与日俱增,锂离子电池因其高安全性和低成本在储能设备中发挥着主导作用。然而,制备具有稳定结构和快速锂扩散、能决定电池性能的先进阴极仍然是一项挑战。对于磷酸铁锂(LFP)而言尤其如此,它作为一种阴极材料,因其低导电效率而存在严重局限性。为提高其导电性,将LFP与缺陷改性的VO复合以制备具有优异电化学性能的LFP/V/C材料,该材料在5 C电流密度下的初始容量为138.85 mAh g,经过500次充放电循环后容量保持率为95%。此外,通过密度泛函理论(DFT)计算详细讨论了缺陷对离子扩散的影响,证实电化学性能的提高与表面包覆混合导电层的引入密切相关。