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《Ceramics International》2020,46(17):26564-26571
Lattice oxygen undergoes redox reaction to achieve high specific capacity of the material in lithium-rich cathode oxides. However, irreversible oxygen loss causes a change in the crystal structure, and the cations migrate in the transition metal layer, resulting in a rearrangement of the electronic structure and ultimately a severe voltage decay. Herein, we introduce Pt nanoparticles with good catalytic activity and electrical conductivity into lithium-rich cathode materials to improve the loss of lattice oxygen for the first time. We have revealed that the evolution of the lattice structure after the lattice oxygen redox reaction is relatively stable in the lithium-rich oxide with Pt nanoparticles, which is in stark contrast to the apparently deformed crystal structure in the lithium-rich oxide without Pt. Pt-containing electrodes exhibit excellent high-capacity retention rate (more than 80% after 200 cycles), and voltage decay is significantly reduced (less than 0.4 V after 200 cycles). Our results highlight the role of Pt nanoparticles in alleviating the loss of lattice oxygen and stabilizing the crystal structure, which opens up the field of vision for the design of high-energy-density lithium rich cathode oxides with stable structure. 相似文献
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《材料科学技术学报》2024,207(0)
The growing need for higher energy density in rechargeable batteries necessitates the exploration of cathode materials with enhanced specific energy for lithium-ion batteries. Due to their exceptional cost-effectiveness and specific capacity, lithium-rich manganese-based cathode materials (LRMs) obtain increasing attention in the pursuit of enhancing energy density and reducing costs. The implementation has faced obstacles in various applications due to substantial capacity and voltage degradation, insufficient safety performance, and restricted rate capability during cycling. These issues arise from the migration of transition metal, the release of oxygen, and structural transformation. In this review, we provide an integrated survey of the structure, lithium storage mechanism, challenges, and origins of LRMs, as well as recent advancements in various coating strategies. Particularly, the significance of optimizing the design of the cathode electrolyte interphase was emphasized to enhance electrode performance. Furthermore, future perspective was also addressed alongside in-situ measurements, advanced synthesis techniques, and the application of machine learning to overcome encountered challenges in LRMs. 相似文献
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这是一篇冶金工程领域的论文。随着2020年以来电池级碳酸锂价格的暴涨,黏土型锂矿提锂技术的研究成为了业界关注的热点。本文以黏土型锂矿资源为研究对象,简述了黏土型锂资源的分布概况,概述了近年来国内有关黏土型锂矿的主要提锂工艺方法,分析了不同方法的优点与不足。针对黏土型锂矿浸出液组成情况,指出综合利用浸出液中的铝等有价组分,加强浸出渣的利用研究对黏土型锂矿开发利用的重要性;展望了具有开发利用潜力的黏土型锂矿浸出提锂方法及浸出液除杂、富集锂的方法,以期为研发较经济合理的黏土型锂矿利用工艺技术有所助益。 相似文献
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《Ceramics International》2021,47(24):34611-34618
An O3 type Li0.6[Li0.2Mn0.8]O2 lithium-rich material has a high reversible capacity due to the synergistic oxidation and reduction of anion and cation. However, the anion oxidation reaction that compensates the charge leads to a partial release of oxygen and the collapse of the structure inevitably. Here, we improve the structural stability of Li0.6[Li0.2Mn0.8]O2 by simultaneously introducing Al ions and B ions. Al ions and B ions randomly occupy octahedral and tetrahedral positions, hindering the migration of Mn ions and expanding the unit cell, resulting in a stable structure and promoting Li+ migration. The co-doped sample has better electrochemical performance than the bare material, and the capacity retention increases from 62.48% to 82.48% after 80 cycles at 0.1C rate, and still provides a capacity of 226 mAh g−1 between 2 and 4.8 V. 相似文献