Constructing a Protective Pillaring Layer by Incorporating Gradient Mn4+ to Stabilize the Surface/Interfacial Structure of LiNi0.815Co0.15Al0.035O2 Cathode
Constructing a Protective Pillaring Layer by Incorporating Gradient Mn4+ to Stabilize the Surface/Interfacial Structure of LiNi0.815Co0.15Al0.035O2 Cathode
复制标题
通过引入梯度 Mn4 构建保护柱层以稳定 LiNi0.815Co0.15Al0.035O2 正极的表面/界面结构
DOI：
10.1021/acsami.8b10372
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发表时间：
2018
影响因子：
9.5
通讯作者：
Xiang W
中科院分区：
文献类型：
--
作者：
Xu Chun-Liu;Wu Zhen-Guo;Xu Ya-Di;Li Yong-Chun;Guo XiaoDong;Zhong Ben-He;Xiang Wei;Xiang Wei;Lv Gen-Pin;Zhang Jun;Chen Ming-Zhe;Guo XD;Xiang W;Xiang W
富镍层状氧化物具有环境友好、成本低、能量密度高等优点，被认为是非常有前途的锂离子电池正极材料。然而，高电位和高温下结构退化导致的循环性能不足和热学特性差给富镍阴极带来了挑战。在LiNi0.815Co0.15Al0.035O2的一次粒子中加入了部分Ni2+离子占据Li板的保护性柱状层，以稳定表面/界面结构。由于富集的Mn4+梯度浓度和类NiO相的柱状效应提供了稳定的外表面，掺锰的四元阴极具有更高的结构稳定性和更好的Li+扩散以及储锂性能。与纯层状结构相比，具有梯度结构的正极材料表现出更稳定的循环行为，在5.0C循环500次后容量保持率为80.0%。
Nickel-rich layered oxides are regarded as very promising materials as cathodes for lithium-ion batteries because of their environmental benignancy, low cost, and high energy density. However, insufficient cycle performance and poor thermotic characteristics induced by structural degradation at high potentials and elevated temperatures pose challenging hurdles for nickel-rich cathodes. Here, a protective pillaring layer, in which partial Ni2+ions occupy Li slabs induced by gradient Mn4+, is integrated into the primary particle of LiNi0.815Co0.15Al0.035O2to stabilize the surface/interfacial structure. With the stable outer surface provided by the enriched Mn4+gradient concentration and the pillar effect of the NiO-like phase, Mn-incorporated quaternary cathodes show enhanced structural stability and improved Li+diffusion as well as lithium-storage properties. Compared with the severe capacity fade of a pure layered structure, the cathode with gradient Mn4+exhibits more stable cycling behavior with a capacity retention of 80.0% after 500 cycles at 5.0 C.