High‐nickel LiNi_1−x−yMn_xCo_yO₂ (NMC) and LiNi_1−x−yCo_xAl_yO₂ (NCA) are the cathode materials of choice for next‐generation high‐energy lithium‐ion batteries. Both NMC and NCA contain cobalt, an expensive and scarce metal generally believed to be essential for their electrochemical performance. Herein, a high‐Ni LiNi_1−x−yMn_xAl_yO₂ (NMA) cathode of desirable electrochemical properties is demonstrated benchmarked against NMC, NCA, and Al–Mg‐codoped NMC (NMCAM) of identical Ni content (89 mol%) synthesized in‐house. Despite a slightly lower specific capacity, high‐Ni NMA operates at a higher voltage by ≈40 mV and shows no compromise in rate capability relative to NMC and NCA. In pouch cells paired with graphite, high‐Ni NMA outperforms both NMC and NCA and only slightly trails NMCAM and a commercial cathode after 1000 deep cycles. Further, the superior thermal stability of NMA to NMC, NCA, and NMCAM is shown using differential scanning calorimetry. Considering the flexibility in compositional tuning and immediate synthesis scalability of high‐Ni NMA very similar to NCA and NMC, this study opens a new space for cathode material development for next‐generation high‐energy, cobalt‐free Li‐ion batteries.

中文翻译：

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高镍NMA：用于锂离子电池的NMC和NCA阴极的无钴替代品。

高镍LiNi ₁ - _{x - y} Mn _x Co _y O ₂（NMC）和LiNi _{1- x - y} Co _x Al _y O ₂（NCA）是下一代高能锂离子电池的正极材料电池。NMC和NCA均包含钴，钴是一种昂贵且稀有的金属，通常被认为对其电化学性能至关重要。这里，高Ni LiNi ₁ - _{x - y} Mn _x Al _y O ₂（NMA）具有理想电化学性能的阴极已证明是相对于内部合成的镍含量相同（89 mol％）的NMC，NCA和Al-Mg掺杂的NMC（NMCAM）进行基准测试的。尽管比容量略低，但高Ni NMA仍能在约40 mV的较高电压下运行，并且相对于NMC和NCA而言，在速率能力上没有任何妥协。在与石墨配对的袋式电池中，高Ni NMA的性能优于NMC和NCA，并且在经过1000个深循环后仅略微落后于NMCAM和商用阴极。此外，使用差示扫描量热法显示出NMA优于NMC，NCA和NMCAM的热稳定性。考虑到与NiA和NMC非常相似的高Ni NMA在成分调整和即时合成可扩展性方面的灵活性，这项研究为下一代高能阴极材料的开发开辟了新的空间，