Inhibit the strain accumulation for 5 V spinel cathode by mitigating the phase separation during high voltage stage
Inhibit the strain accumulation for 5 V spinel cathode by mitigating the phase separation during high voltage stage
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DOI：
10.1016/j.nanoen.2023.109215
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发表时间：
2023-12
期刊：
影响因子：
17.6
通讯作者：
Saiyue Liu;Xiang Liu;Dongsheng Ren;Tianyi Li;Liang Yi;Wei Liu;Juping Xu;Tiening Tan;Jiahao Zhang;Yukun Hou;Yi Guo;Gaolong Zhu;Shuo Yin;Guohe Yuan;Yi Weng;Guohua Ma;Zuling Peng;Xiang Zheng;Wen Yin;Languang Lu;Minggao Ouyang
中科院分区：
文献类型：
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作者：
Saiyue Liu;Xiang Liu;Dongsheng Ren;Tianyi Li;Liang Yi;Wei Liu;Juping Xu;Tiening Tan;Jiahao Zhang;Yukun Hou;Yi Guo;Gaolong Zhu;Shuo Yin;Guohe Yuan;Yi Weng;Guohua Ma;Zuling Peng;Xiang Zheng;Wen Yin;Languang Lu;Minggao Ouyang
LiNi0.5Mn1.5O4（LNMO）尖晶石正极材料具有原料成本低、工作电压高、锂离子传输通道好等优点，是一种很有潜力的高功率、低成本锂离子电池正极材料。然而，LNMO在充/放电过程中由于两相转变而遭受结构稳定性，导致循环性能差。为了解决这些问题，我们已经构建了一个均匀的聚集LNMO阴极与多方面的初级粒子，即LNMO与单晶二次粒子（SSP LNMO）。同步辐射X射线衍射、中子衍射和全软包电池等表征结果表明，SSP LNMO在脱锂/锂化过程中表现出单一的固溶体反应和有限的晶格演化。这与普通的LNMO阴极相反，后者在高压下表现出从尖晶石Li 1 − xNi0.5Mn1.5O4到岩盐MnO 2的显著两相转变。因此，与普通LNMO阴极相比，SSP LNMO具有大大提高的循环寿命。总体而言，本研究表明了基于一次晶粒形貌调制构建LNMO以提高LIB的本征稳定性的可能性。
LiNi0.5Mn1.5O4(LNMO) spinel cathode is a potential cathode material for high-power, low-cost lithium-ion batteries (LIBs) due to its low raw material cost, high operating voltage and efficient lithium-ion transport channel. However, LNMO suffers from structural stability due to the two-phase-transformation during charge/discharge process, leading to poor cycling performance. To address the issues, we have constructed a homogeneous aggregated LNMO cathode with a multifaceted primary particle, namely the LNMO with single-crystal secondary particles (SSP LNMO). Ex situ and in situ characterizations including the synchrotron X-ray diffraction, the neutron diffraction and full pouch cell validated that the SSP LNMO exhibit a single solid-solution reactions with a restrained lattice evolution during the delithiation/ lithiation process. This is in contrast to the normal LNMO cathode, which demonstrates a significant two-phase transition from spinel Li1−xNi0.5Mn1.5O4to rock-salt MnO2at high voltage. Therefore, the SSP LNMO has greatly improved cycle life compared to the normal LNMO cathode. Overall, this study demonstrates the possibility of constructing LNMO based on primary-grain morphology modulation to improve the intrinsic stability of LIBs.