Ni-rich cathode materials have drawn lots of attention owing to its high discharge specific capacity and low cost. Nevertheless, there are still some inherent problems that desiderate to be settled, such as cycling stability and rate properties as well as thermal stability. In this article, the conductive polymers that integrate the excellent electronic conductivity of polyaniline (PANI) and the high ionic conductivity of poly(ethylene glycol) (PEG) are designed for the surface modification of LiNiCoMnO cathode materials. Besides, the PANI-PEG polymers with elasticity and flexibility play a significant role in alleviating the volume contraction or expansion of the host materials during cycling. A diversity of characterization methods including scanning electron microscopy, energy-dispersive X-ray spectrometer, transmission electron microscopy, thermogravimetric analysis, Fourier transform infrared have demonstrated that LiNiCoMnO cathode materials is covered with a homogeneous and thorough PANI-PEG polymers. As a result, the surface-modified LiNiCoMnO delivers high discharge specific capacity, excellent rate properties, and outstanding cycling performance.

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Ni‐rich layered LiNi0.8Mn0.1Co0.1O2 (NCM811) cathode material has promising prospects for high capacity batteries at acceptable cost. However, LiNi0.8Mn0.1Co0.1O2 cathode material suffers from surface structure instability and capacity degradation upon cycling. In this study, in situ ZrP2O7 coating is introduced to provide a protective structure. The optimum modification amount is 1.0 wt %. A series of characterization methods (X‐ray diffraction, high‐resolution transmission electron microscopy, and X‐ray photoelectron spectroscopy) verify the generation and structure of the coating layer. Electrochemical performance tests demonstrate that the cycle retention rate increases from 66.35 to 86.92 % after 100 cycles at 1 C rate. The dense inorganic pyrophosphate layer not only has chemical stability against the electrolyte but also eliminates surface residual lithium. The protective layer and the matrix are strongly joined by high‐temperature heating, thereby giving a certain mechanical strength and protecting the overall structure of the topography. Therefore, the cycle and rate performance are enhanced by the modification with ZrP2O7.

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Uniform olive‐like Ni0.8Co0.1Mn0.1CO3 carbonate precursors were successfully synthesized under hydrothermal conditions. Powder X‐ray diffraction, field emission scanning electron microscopy, optical microscopy, and inductively coupled plasma optical emission spectroscopy revealed that crystal size and elemental contents of carbonate precursors could be slightly tuned by regulating the molar ratio of urea and transition metal ions, moreover, a synergetic crystal evolution mechanism involving Ostwald ripening and crystal etching for the formation of olive‐like carbonate precursors was put forward for the first time. The improvement in temperature facilitated the increment in size of primary particles of oxides transformed from carbonate precursors. Vermiform LiNi0.8Co0.1Mn0.1O2 cathode materials transformed from olive‐like carbonate precursors exhibited high discharge capacity of 193.4 mAh g−1 at 0.2 C, and capacity retention of 85.4 % at 1 C after 100 cycles. Charge transfer impedance (Rct) and diffusion coefficient of lithium ion (DLi+) revealed the electrochemical properties of cathode materials.

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