POWDER MATERIAL FOR NEGATIVE ELECTRODE OF LITHIUM ION BATTERY AND PRODUCTION METHOD THEREOF

• Main Authors: KIMURA YUTA, MINAMI KAZUKI
• Format: Patent
• Language: English; Japanese
• Published: 27.09.2021
• Subjects: BASIC ELECTRIC ELEMENTS; CHEMISTRY; COMPOUNDS THEREOF; ELECTRICITY; INORGANIC CHEMISTRY; METALLURGY; NON-METALLIC ELEMENTS; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

To provide a powder material for a negative electrode of a lithium ion battery, which can suppress an electrolyte solution decomposition reaction during charge and discharge, and improve the cycle characteristic.SOLUTION: A powder material for a negative electrode of a lithium ion battery comprises Si, O and as an element X, one or more elements selected from a group consisting of Cu, Ti, Co, Fe, Ni and Zr, and it has a Si phase and a Si-X compound phase. When a short diameter in a cross section of a powder particle is denoted by "a", an internal oxygen concentration is 0.2 mass% or more and 7.0 mass% or less in an internal region which is apart from the surface of the powder particle by 0.2a or a larger distance.SELECTED DRAWING: None 【課題】充放電時の電解液分解反応を抑制し、サイクル特性を改善させることが可能なリチウムイオン電池の負極用粉末材料を提供する。【解決手段】リチウムイオン電池の負極用粉末材料は、Ｓｉ、Ｏおよび元素ＸとしてＣｕ，Ｔｉ，Ｃｏ，Ｆｅ，Ｎｉ，Ｚｒよりなる群の中から選択された１種以上の元素を含有し、Ｓｉ相およびＳｉ−Ｘ化合物相を備え、粉末粒子断面における短径をａとしたとき、粉末粒子の表面から０．２ａ以上離間した内部領域における内部酸素濃度が０．２質量％以上、７．０質量％以下とされている。【選択図】 なし