Ni-rich LiNi0·8Co0·1Mn0·1O2 coated with Li-ion conductive Li3PO4 as competitive cathodes for high-energy-density lithium ion batteries
Ni-rich LiNi0·8Co0·1Mn0·1O2 coated with Li-ion conductive Li3PO4 as competitive cathodes for high-energy-density lithium ion batteries
复制标题
涂覆锂离子导电Li3PO4的富镍LiNi0·8Co0·1Mn0·1O2作为高能量密度锂离子电池的竞争性正极
DOI：
10.1016/j.electacta.2020.135871
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发表时间：
2020
影响因子：
6.6
通讯作者：
Changzhou Yuan
中科院分区：
文献类型：
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作者：
Wenheng Zhang;Longwei Liang;Fei Zhao;Yang Liu;Linrui Hou;Changzhou Yuan
近年来，富镍LiNi 0·8 Co 0·1 Mn 0·1 O2（NCM 811）正极材料在锂离子电池中的应用引起了人们极大的兴趣。但由于所涉及的表面/界面问题，其在循环时仍然遭受严重的容量退化。本文首先提出了一种有效的表面改性策略，原位制备了固体电解质Li 3 PO 4包覆的NCM 811，并系统地研究了Li 3 PO 4纳米包覆层对NCM 811作为LIB竞争阴极的电化学稳定性的影响。Li+导电Li 3 PO 4的智能表面涂层降低了对H2O和CO2的敏感性，缓解了应变诱导的晶间微裂纹的演化，减缓了HF腐蚀，并保持了适当涂层含量的Li+快速扩散系数。优化后的NCM811@Li3PO4正极在可逆容量、容量保持率和速率行为方面表现出优异的电化学储锂性能。更具竞争力的是，基于NCM811@Li3PO4的袋型器件在1.0 C温度下经过250次循环后，电池级能量密度为304.6 Wh kg−1，沿着的容量保持率为89.6%。这些吸引人的特性突出了所得到的NCM811@Li3PO4阴极在下一代LIB中的应用前景。
Recently, the Ni-rich LiNi0·8Co0·1Mn0·1O2(NCM811) cathode with high-energy applications has received tremendous interest for Li-ion batteries (LIBs). But it still suffers from serious capacity degradation upon cycling owing to the involved sur-/interface issues. In the work, we first propose an efficient surface modification strategy toin-situfabricate the NCM811 coated with solid electrolyte Li3PO4, and systematically investigate the effect of Li3PO4nano coating layer on electrochemical stability of the NCM811 for LIBs as competitive cathodes. It is the smart surface coating of Li+conductive Li3PO4that lowers the sensitivity to H2O and CO2, relieves the evolution of strain-induced intergranular micro-cracks, slows the HF corrosion, and retains the fast Li+diffusion coefficients with appropriate coating content. The optimized NCM811@Li3PO4cathode yields the remarkable electrochemical Li-storage properties in terms of reversible capacities, capacity retention and rate behaviors. More competitively, the NCM811@Li3PO4based pouch-type devices deliver a cell-level energy density of ∼304.6 Wh kg−1, along with a capacity retention of 89.6% over 250 cycles at 1.0 C. The appealing features highlight promising application of the resultant NCM811@Li3PO4cathodes in next-generation LIBs.