NEGATIVE ELECTRODE ACTIVE MATERIAL AND LITHIUM ION SECONDARY BATTERY HAVING THE SAME

• Main Author: MATSUBARA SHINSUKE
• Format: Patent
• Language: English; Japanese
• Published: 16.06.2022
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

To provide a negative electrode active material that can realize an excellent low-temperature characteristic.SOLUTION: The negative electrode active material for a lithium ion secondary battery disclosed herein includes: a carbon material 82 capable of reversibly occluding and discharging lithium ions; and a carbon coating target layer 84 formed on a surface of the carbon material 82. The carbon coating target layer 84 has a carbon atom and a phosphorus atom. When the peak of a P2p spectrum measured by an X-ray photoelectron spectroscopy (XPS) in the carbon coating target layer 84 is waveform-separated, the peak is located in where the binding energy is 131 eV.SELECTED DRAWING: Figure 3 【課題】優れた低温特性を実現し得る負極活物質を提供する。【解決手段】ここで開示されるリチウムイオン二次電池用の負極活物質は、リチウムイオンを可逆的に吸蔵および放出可能な炭素材料８２と、炭素材料８２の表面に形成された炭素被覆層８４と、を備えており、炭素被覆層８４は、炭素原子と、リン原子とを備えている。さらに、炭素被覆層８４において、Ｘ線光電子分光法（ＸＰＳ）によって測定されるＰ２ｐスペクトルのピークを波形分離したとき、結合エネルギーが１３１ｅＶの位置にピークを有する。【選択図】図３