Novel cathode material for lithium rechargeable battery : graphite intercaration compounds of some transition metal chlorides

新型锂二次电池正极材料：某些过渡金属氯化物的石墨插层化合物

• 批准号: 09450321
• 负责人: KISHI Tomiya
• 金额: $ 9.09万
• 依托单位: Keio University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09450321/
• 关键词: Graphite intercaration compounds; lithium secondary battery; cobalt dichloride; niobium pentachloride; transient metal chlorides; 二塩化コバルト; 塩化コバルト

Graphite intercalation compounds (GIC) of some transition metal chlorides have rigid layered structures and high electronic conductivity. In this study, electrochemical insertion of lithium into the GICs of some transition metal chlorides was investigated in order to apply the GICs to the cathode materials for lithium secondary batteries.The discharge and charge characteristics of a 1st stage GIC of cobalt dichloride, CィイD25.5ィエD2CoCィイD2l2.2ィエD2, was investigated in various organic electrolytes containing 1 M LiClOィイD24ィエD2. The kinds of organic electrolytes did not affect the potentials during insertion of lithium but the amounts of accommodated lithium in the GIC. X-ray diffraction of the GIC showed that the layered structures were broken after insertion of lithium. Furthermore, the extraction of lithium from the lithiated GICs was almost impossible.The electrochemical lithiation behavior of a 4th stage GIC of niobium pentachloride, CィイD224ィエD2NbCiィイD25.2ィエD2, was investigated in 1 M LiClOィイD24ィエD2 / PC electrolyte. The layered structure of the GIC was preserved during reduction from pentavalent to tetravalent. However, the extraction of lithium from the lithiated GIC was impossible. Furthermore, the liberation of chloride ions from the GIC occurred irreversibly during reduction from tetravalent to trivalent.These results showed that the GICs of both cobalt and niobium chlorides are not suitable for cathode materials for lithium secondary batteries. However, it was suggested that lithium can be inserted into the higher stage GICs containing the transition metals which can take various valence states without destruction of the layered structures.

某些过渡金属氯化物的石墨嵌入化合物具有刚性的层状结构和较高的电子导电性。本文研究了将锂电化学插入过渡金属氯化物的GICs中，从而将GICs应用于锂二次电池正极材料。研究了含1 μ M LiClO μ l μ l D24 μ l μ l D2的二氯化钴一级GIC的放电和充电特性。有机电解质的种类不影响插入锂时的电位，但影响GIC中容纳锂的量。x射线衍射结果表明，锂离子的加入破坏了GIC的层状结构。此外，从锂化gic中提取锂几乎是不可能的。研究了五氯化铌第4期GIC C‑‑D224‑r2nbci‑r25.2‑r2d2在1 M LiClO‑r24‑r2d2 / PC电解液中的电化学锂化行为。在从五价到四价的还原过程中，GIC的层状结构得以保留。然而，从锂化GIC中提取锂是不可能的。此外，氯离子在从四价还原到三价的过程中从GIC中释放是不可逆的。结果表明，氯化钴和氯化铌均不适合作为锂二次电池正极材料。然而，有人认为锂可以插入到含有各种价态过渡金属的高阶gic中，而不会破坏层状结构。

项目成果

A.Adachi,Y.Katayama,T.Miura and T.Kishi: "Anodic behavior of a carbon plate in an LiCl-KCl binary molten salt" J.Power Sources. 68. 348-351 (1997)

A.Adachi、Y.Katayama、T.Miura 和 T.Kishi：“碳板在 LiCl-KCl 二元熔盐中的阳极行为”J.Power Sources。