POROUS SILICON-BASED ANODE ACTIVE MATERIAL, METHOD FOR PREPARING THE SAME, AND LITHIUM SECONDARY BATTERY COMPRISING THE SAME

• Main Authors: YOO JUNG WOO, LEE MI-RIM, YOON JI HYUN, BANG BYOUNG MAN, LEE MI KYEONG, LEE HAN HO, LEE CHANG RAE, LEE YONG-JU, KIMU EUN-KYUN, JEONG IL KYO
• Format: Patent
• Language: English; Japanese
• Published: 02.08.2018
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

PROBLEM TO BE SOLVED: To provide a silicon-based anode active material which reduces the occurrence of an electrical short circuit in an electrode and the volume expansion rate and improves lifetime characteristics of a secondary battery.SOLUTION: An anode active material comprises a carbon-based anode active material and porous SiOparticles (0≤x<2). The porous SiOparticles 1 comprise an oxide film layer 2 applied to surfaces thereof. The porous SiOparticles are porous Si particles. The thickness of the oxide film layer is from 40 nm to 200 nm inclusive. The specific surface area of the porous SiOparticles is from 5 m/g to 50 m/g.SELECTED DRAWING: Figure 1 【課題】電極内での電気的短絡の発生及び体積膨張率を減少させ、二次電池の寿命特性を向上させたシリコン系負極活物質の提供。【解決手段】炭素系負極活物質と、多孔性ＳｉＯx粒子（０≦ｘ＜２）とを含んでなり、前記多孔性ＳｉＯx粒子１が、表面にコーティングされた酸化膜層２を含んでなり、前記多孔性ＳｉＯx粒子が、多孔性Ｓｉ粒子であり、前記酸化膜層の厚さが、４０ｎｍ以上２００ｎｍ以下であり、前記多孔性ＳｉＯx粒子の比表面積が、５ｍ2／ｇから５０ｍ2／ｇであることを特徴とする、負極活物質。【選択図】図１