An ultrathin MgO coating was synthesized via atomic layer deposition (ALD) to improve the surface properties of the Li[Ni_0.5Mn_0.3Co_0.2]O₂ (NMC) cathode. An in-situ quartz crystal sensor was used to monitor the “self-limiting” surface reactions during ALD process and estimate the density of the deposited film. The electrochemical performance of the MgO-coated NMC cathode was evaluated in a half-cell assembly and compared to other ALD-based coatings, such as Al₂O₃ and ZrO₂. Cyclic voltammetry studies suggested that ALD MgO has a higher Li-diffusion coefficient which resulted in lower overpotential on the NMC cathode surface and improved Li-ion battery rate performance. MgO-coated NMC also yielded improved capacity retention over uncoated NMC in a long-range cycling test.

中文翻译：

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原子层沉积的MgO：Li [Ni _0.5 Mn _0.3 Co _0.2 ] O ₂阴极的低电位涂层

通过原子层沉积（ALD）合成了超薄MgO涂层，以改善Li [Ni _0.5 Mn _0.3 Co _0.2 ] O ₂（NMC）阴极的表面性能。使用原位石英传感器监测ALD过程中的“自限”表面反应并估算沉积膜的密度。在半电池组件中评估了涂有MgO的NMC阴极的电化学性能，并将其与其他基于ALD的涂层（如Al ₂ O ₃和ZrO _{2）进行了比较。}。循环伏安法研究表明，ALD MgO具有较高的锂扩散系数，这导致NMC阴极表面的过电势较低，并改善了锂离子电池的倍率性能。在远距离循环测试中，MgO涂层NMC的容量保持性也比未涂层NMC更高。