NEGATIVE ELECTRODE ACTIVE MATERIAL PARTICLES

• Main Authors: OSAWA RYOSUKE, TSUJIKO AKIRA, INOUE KAORU
• Format: Patent
• Language: English; Japanese
• Published: 26.03.2020
• 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 improve cycle characteristics of negative electrode active material particles containing silicon.SOLUTION: Negative electrode active material particles 10 each include a core particle 11 and a coating film 12. The coating film 12 covers at least a part of the surface of the core particle 11. The core particle 11 contains at least silicon. The coating film 12 contains a first component and a second component. The first component is fluorine. The second component is at least one selected from the group consisting of boron and phosphorus. A bond is formed between silicon contained in the core particle 11 and the first component. A bond is formed between silicon contained in the core particle 11 and the second component. The concentration of the first component is 10 atom% or more and the concentration of the second component is 2 atom% or more on the surface of the negative electrode active material particles 10.SELECTED DRAWING: Figure 1 【課題】珪素を含む負極活物質粒子のサイクル特性を向上させること。【解決手段】負極活物質粒子１０はコア粒子１１および被膜１２を含む。被膜１２は、コア粒子１１の表面の少なくとも一部を被覆している。コア粒子１１は珪素を少なくとも含む。被膜１２は第１成分および第２成分を含む。第１成分はフッ素である。第２成分はホウ素およびリンからなる群より選択される少なくとも１種である。コア粒子１１に含まれる珪素と、第１成分との間に結合が形成されている。コア粒子１１に含まれる珪素と、第２成分との間に結合が形成されている。負極活物質粒子１０の表面において、第１成分の濃度は１０原子％以上であり、かつ第２成分の濃度は２原子％以上である。【選択図】図１