COATED CATHODE ACTIVE MATERIAL AND MANUFACTURING METHOD THEREOF

• Main Authors: KIKUCHI TAKESHI, NAITO MAKIO, OZAWA TAKAHIRO, IMAIZUMI JUNICHI, IMAZAKI MITSUYASU
• Format: Patent
• Language: English; Japanese
• Published: 13.10.2022
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

To provide a cathode active material capable of suppressing gas generation owing to the oxidative decomposition of a nonaqueous electrolyte in a lithium ion secondary battery arranged by use of a cathode active material that operates at a high electric potential, and a manufacturing method thereof.SOLUTION: A coated cathode active material comprises a cathode active material coated with a lithium ion-conducting oxide. The cathode active material is a lithium-conducting active material of which the operation voltage is equal to or higher than 4.5 V of a melting-deposition potential reference of lithium metal. The lithium ion-conducting oxide is amorphous below 600°C. The coated cathode active material is a transparent sol comminuted to a particle size of 10 nm or less according to a small angle X-ray scattering method.SELECTED DRAWING: None 【課題】高電位で作動する正極活物質を用いたリチウムイオン二次電池において、非水電解質の酸化分解によるガスの発生を抑制できる正極活物質、及びその製造方法を提供する。【解決手段】正極活物質がリチウムイオン伝導性酸化物で被覆された被覆正極活物質であって、前記正極活物資は、作動電圧がリチウム金属の溶解析出電位基準である４．５Ｖ以上のリチウム伝導性活物質であり、前記リチウムイオン伝導性酸化物は、６００℃未満において非晶質であり、且つ、Ｘ線小角散乱法による粒子径が１０ｎｍ以下に粉砕された透明ゾルであることを特徴とする、被覆正極活物質。【選択図】なし