High Cycling Stability of the LiNi_0.8Co_0.1Mn_0.1O₂ Cathode via Surface Modification with Polyimide/Multi‐Walled Carbon Nanotubes Composite Coating

Abstract

because the transition metal (Ni, Co, and Mn) ions dissolve from the cathode active materials and the side reactions occur with the electrolyte, resulting in poor cycling performance. [9][10][11][12] Furthermore, the LiNi 0.8 Co 0.10 Mn 0.1 O 2 (NCM811) material shows secondary crystal cracking and volume expansion under a fully charged state, which is enough to cause an expanding crack near the grain boundary inside the particle, so it causes poor cyclic stability. [13] The research shows that the volume expansion and contraction of NCM811 can reach 3.9% during the delithiation/lithiation process, which is enough to cause an expanding crack near the grain boundary inside the particle. [13,14] Continuous new cracks in the material particles expose fresh surfaces and continue to react with the electrolyte, resulting in pulverization of the electrode materials and battery failure. At present, coating methods to solve these problems include single-layer coatings, such as SiO 2 , [15

Toward Superior Low-Temperature Performance and Safe Cathode Slurry Fabrication via 3-Methoxy-N,N-dimethylpropionamide as a Low-Toxicity and Facile Solvent

“…The XRD patterns of pristine NCM811-NMP and NCM811-MDMPA after 700 cycles are shown in Figure . The pristine samples can be indexed to layered hexagonal α-NaFeO 2 structures with a space group of R 3̅ m . − The characterized diffraction peaks in the MDMPA cathodes are in good correspondence with previous reports. The obvious peak splitting of (110)/(018) indicates an orderly layered structure in the two samples.…”

Polyimides as Promising Materials for Lithium-Ion Batteries: A Review

“…First, researchers could use monomers with different structures to synthesize PI coatings with targeted performance. Second, to improve the electrochemical performance, inorganic materials (such as Al 2 O 3 , ZrO 2 , and TiO 2 ), electron-conducting materials (such as graphene, carbon nanotubes, and carbon black), and their mixtures can be compounded with PIs to achieve co-coating layers [ 119 , 120 ]. Third, self-healing, heat conductive, fluorescence, etc., functions can be introduced to PIs to realize the functionalization of cathode materials.…”

Research Progress on Doping and Coating of High-Nickel Cathode Materials for Lithium-Ion Batteries

“…Surface coating can improve the stability of the surface structure of the material, promote the transfer of electrons on the surface of the material, and prolong the service life of the material. At present, commonly used coating materials include carbon materials (amorphous carbon [48][49][50], graphene [51][52][53], carbon nanotubes [54,55]), phosphate (Li3PO4 [56][57][58], LiFePO4 [59], MnPO4 [60]), fluoride (CaF2 [61], AlF3 [62], LiF [63]), oxides (LiBO3 [64], LiWO3 [65], Li2TiO3 [66], WO3 [67], SiO2 [68], Al2O3 [69], CeO2 [70]) etc.…”