The syntheses of Ni-poor (NCM111, LiNi_1/3Co_1/3Mn_1/3O₂) and Ni-rich (NCM811 LiNi_0.8Co_0.1Mn_0.1O₂) lithium transition-metal oxides (space group R3̅m) from hydroxide precursors (Ni_1/3Co_1/3Mn_1/3(OH)₂, Ni_0.8Co_0.1Mn_0.1(OH)₂) are investigated using in situ synchrotron powder diffraction and near-edge X-ray absorption fine structure spectroscopy. The development of the layered structure of these two cathode materials proceeds via two utterly different reaction mechanisms. While the synthesis of NCM811 involves a rock salt-type intermediate phase, NCM111 reveals a layered structure throughout the entire synthesis. Moreover, the necessity and the impact of a preannealing step and a high-temperature holding step are discussed.

中文翻译：

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用同步辐射监测锂离子电池贫镍和富镍氧化物阴极材料的形成

_{贫镍 (NCM111, LiNi 1/3} Co _1/3 Mn _1/3 O ₂ ) 和富镍 (NCM811 LiNi _0.8 Co _0.1 Mn _0.1 O ₂ ) 锂过渡金属氧化物（空间群R 3̅m）的合成来自氢氧化物前体（Ni _1/3 Co _1/3 Mn _1/3 (OH) ₂ , Ni _0.8 Co _0.1 Mn _0.1 (OH) _{2 ）的}原位研究同步加速器粉末衍射和近边X射线吸收精细结构光谱。这两种阴极材料的层状结构的发展是通过两种完全不同的反应机制进行的。NCM811 的合成涉及岩盐型中间相，而 NCM111 在整个合成过程中显示出层状结构。此外，讨论了预退火步骤和高温保持步骤的必要性和影响。