鋰離子電池高鎳層狀結構正極材料 Ni-rich LiNixMnyCozO2 (NMC, x ≥ 0.6)已被視為下世代商用正極材料，因此合成出純相 NMC 三元正極材料為一重要研究課題。最近，單晶顆粒正極已成為一個重要的目標，因為它們的高結構完整性，可以改善多晶顆粒內電化學引起的破裂導致的嚴重容量下降，但傳統的合成方法中因高溫煅燒、助熔劑的殘留嚴重阻礙了其工業應用。本論文採用 Modified Pechini Sol-gel 法來解決傳統合成上的難題，並運用平衡常數反應式計算各類合成條件對溶液中各物種平衡濃度的影響，判斷出最佳的合成條件，以優化煅燒條件以成功合成出純相近單晶NMC811，並擁有高層狀結構結晶度、低鋰鎳金屬離子混合的微米級粉體。

The Ni-rich layered structure cathode material Ni-rich LiNixMnyCozO2(NMC, x ≥ 0.6) has been considered the next-generation commercial cathode material for lithium-ion batteries. Therefore, the synthesis of single-phase NMC ternary cathode materials is a significant research topic. Recently, single-crystal particle cathodes have become a crucial research topic as their high structural integrity can improve the severe capacity degradation resulting from electrochemically-induced intergranular cracking within the polycrystalline particles. However, high-temperature calcined and flux residue products in traditional single-crystal synthesis methods seriously hinder its industrial applications. This study employs a modified Pechini sol-gel method to solve the problem of traditional synthesis methods to produce single-crystal NMC cathodes. Furthermore, using the thermodynamic equilibrium constant method to calculate the impact of various synthesis conditions on the equilibrium concentration of each species in the solution. Finally, by optimized calcination conditions, micron quasisingle-crystal NMC811 powder with high-level structure crystallinity and low cation mixing was successfully synthesized.

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