Full concentration gradient (FCG)‐Ni_1−x−yCo_xMn_y(OH)₂ is generally synthesized via varying the molar ratio of metal ions in feeding flow during coprecipitation. Accordingly, pH and [N] (ammonia concentration) should change with the reaction time given that the optimum pH and [N] are different with variations of x or y. Hence, the effect of the controlling strategies of pH and [N] on preparing the FCG‐precursor is explored, and the mechanism behind is revealed. The FCG‐precursor with the covariation of pH and [N] has the densest and firmest structure, highest tap density (2.115 g mL⁻¹), and a well‐ordered layered crystal structure. In addition, its discharge capacity can reach as high as 189.4 mAh g⁻¹ (capacity retention of 96.3%) after 200 cycles at 1 C rate, which is 9.1% and 15.8% higher than FCG‐NCM811 with constant pH, [N], and Homo‐NCM811. The match between pH and [N] is crucial to obtain the favorable FCG‐precursor and ‐NCM811.

中文翻译：

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pH和氨浓度的控制策略对中试反应器中共沉淀制备全浓度梯度Ni0.8Co0.1Mn0.1（OH）2的影响

通常通过改变共沉淀过程中进料流中金属离子的摩尔比来合成全浓度梯度（FCG）-Ni _{1- x - y} Co _x Mn _y（OH）₂。因此，假定最佳pH和[N]随x或y的变化而不同，则pH和[N]（氨浓度）应随反应时间而变化。因此，探讨了pH和[N]控制策略对制备FCG前体的影响，并揭示了其机理。具有pH和[N]共同变化的FCG前体具有最稠密和最牢固的结构，最高堆积密度（2.115 g mL ^-1），以及层状晶体结构井然有序。此外，在1 C速率下200次循环后，其放电容量可高达189.4 mAh g ^-1（容量保持率96.3％），比恒定pH值的FCG-NCM811高9.1％和15.8％。和Homo‐NCM811。pH和[N]之间的匹配对于获得良好的FCG前体和-NCM811至关重要。