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The research of high-performance cathode materials for rechargeable lithium-ion batteries (LIBs) is highly desirable. The ternary layered oxide LiNi1/3Co1/3Mn1/3O2 (LNCM) is a promising cathode material for LIBs due to its high discharge voltage, large specific capacity, good thermostability, and low cost. However, the LNCM cathode still has certain limitations, including cationic mixing and low electronic conductivity. These drawbacks ultimately result in poor cycling stability, rapid voltage degradation, and capacity loss during high-rate cycling. To address these issues, we have established a feasible sol-gel method combined with calcination to prepare LNCM, which can significantly improve the electrochemical activity of the LNCM cathode. The developed LNCM−850/10 cathode displays an initial specific discharge capacity of 215.3 mAh g−1 at a current rate of 0.2 C and retains a high reversible capacity of 93.9 mAh g−1 after 200 cycles. In addition, the LNCM−850/10 cathode also exhibits excellent high-rate charge-discharge capability and high-rate cycling performance. These remarkable results are probably due to the low Li+/Ni2+ cation mixing degree, good particle morphology, and uniform particle size distribution of LNCM−850/10, which effectively improves the electronic conductivity and lowers the charge transfer resistance, while reducing the Li+ diffusion distance and accelerating the insertion/extraction of Li+. Our study demonstrates that careful control of the calcination temperature of sol-gel-synthesized LNCM precursors can promote the development of LNCM cathodes suitable for advanced LIBs. [ABSTRACT FROM AUTHOR]

The development of high‐performance cathode materials for next‐generation lithium‐ion batteries (LIBs) is urgently needed. Among the potential cathode candidates, ternary layer oxide LiNi1/3Co1/3Mn1/3O2 (LNCM) has attracted considerable attention due to its high voltage discharge, large theoretical specific capacity, stable chemical structure and low cost. However, Li+/Ni2+ cation mixing and low conductivity have resulted in poor long‐term cyclability, voltage drop and capacity degradation during high‐rate charging. To address these issues, a sol‐gel technique together with an annealing treatment was used to prepare LNCM with well‐defined structure and good morphology. The material obtained by heating the LNCM precursor at 850 °C for 12 h (LNCM‐850/12) exhibited an initial discharge specific capacity of 217.9 mAh g−1 at 0.2 C and maintained a high reversible capacity of 116.1 mAh g−1 after 200 cycles. The LNCM‐850/12 electrode also demonstrated superior rate capacity and exceptional cycling stability due to its well‐defined structure, low Li+/Ni2+ cation mixing and good morphology. These characteristics improve the electrical/ionic conductivity, reduce the charge transfer resistance and shorten the Li+ diffusion distance, ultimately accelerating the Li+ insertion and extraction. Overall, the careful control of calcination time in LNCM synthesis provides valuable insights for the development of advanced cathodes for LIBs. [ABSTRACT FROM AUTHOR]

Summary: Polypyrrole is successfully introduced to enhance the reaction stability and ionic conductivity of LiNi1/3Co1/3Mn1/3O2 material through an ultrasound dispersion method and applied as cathode materials for lithium‐ion batteries. This polymer can significantly advance the electrochemical properties. Expectedly, the 8 wt.% LiNi1/3Co1/3Mn1/3O2/polypyrrole composite has lower mixing degree of Li+/Ni2+, higher c/a value, which delivers the first discharge capacity of 199.2 mAh g−1, which abate to 121.3 mAh g−1 in the 300th cycle at 0.2 C between 2.5 and 4.5 V. Even at 3 C, it continues to reveal a reversible capacity of 86.4 mAh g−1 after 100 cycles. All the consequences implied that the 8 wt.% LiNi1/3Co1/3Mn1/3O2/polypyrrole verified a minor charge transfer resistance and better Li+ diffusion ability, hence establishing preferable rate and cycling performance compared with the primordial LiNi1/3Co1/3Mn1/3O2. [ABSTRACT FROM AUTHOR]

Ethylene glycol‐assisted sol‐gel method is employed for preparing LiNi1/3Co1/3Mn1/3O2 used as cathode material in lithium‐ion batteries. The prepared material has higher c/a value and lower cationic mixing degree of Li+/Ni2+, illuminating a more orderly structure, smaller particle size and more regular particle shape, which shorten the diffusion length for Li+ ions and allow the rapid kinetics of Li+ ions diffusion. Sure enough, the as‐prepared LiNi1/3Co1/3Mn1/3O2 material displays the first discharge capacity of 208 mAh g−1 and keeps 133 mAh g−1 after 200 cycles between 2.5 and 4.5 V at 0.2 C. In addition, it demonstrates excellent rate capacity of 143 mAh g−1 at 2 C. The results show that LiNi1/3Co1/3Mn1/3O2 prepared by this method has high discharge capacity, admirable rate capability and exceptional cycle stability, which provides significant insights into the synthesis of other layered oxides as cathode materials for lithium‐ion batteries. [ABSTRACT FROM AUTHOR]