分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2017-05-02
摘要: Hexamethylene diisocyanate can chemically react with the onium ion produced by the oxidation of propylene carbonate and in situ generate a novel interfacial layer that is stable at high potential. With an appropriate thickness of this film, LiNi1/3Co1/3Mn1/3O2 presents significantly improved rate and cycle performances when tested between 2.5 and 4.6 V (vs. Li/Li+).
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2017-05-02
摘要: In this work, we investigate the influence of oxygen non-stoichiometry on the characteristics of LiNi0.8Co0.1Mn0.1O2 cathode material. Among the investigated samples, the level of Ni/Li disorder in the bulk and the thickness of auto-generated layer on the surface share the same trend as the amount of oxygen loss in LiNi0.8Co0.1Mn0.1O2 materials. It indicates that the aforementioned key structural in- stabilities should be tightly related to the oxygen defects and the induced structural relaxation. As a consequence of structural entirety, the sample with the least defects presents the highest discharge capacity (192.9 mAhg 1 at 0.1C), the best rate capability (160.1 mAhg 1 at 5C), and the most stable cyclibility (89.9% at 200th). Our results demonstrate that oxygen deficiency plays a key role to determine the electrochemical performance of high-nickel cathode materials.
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2017-05-02
摘要: A surface protective structure to efficiently improve the cyclic stability and lifetime of the lithium metal electrode is investigated. By volu- metrically confining plated lithium metal in the inter-space of a ceramic porous layer and isolating the confined lithium via a rein- forced skin-layer from attack by electrolyte solvents, the coulombic efficiency of the protected lithium metal electrode reaches very high values of $97–99%.