NEGATIVE ELECTRODE AND NONAQUEOUS ELECTROLYTE SECONDARY BATTERY INCLUDING THE NEGATIVE ELECTRODE

• Main Authors: TSUJIKO AKIRA, MORIKAWA ARINORI
• Format: Patent
• Language: English; Japanese
• Published: 20.12.2022
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

To provide a negative electrode which achieves both improvement in a cycle life of a nonaqueous electrolyte secondary battery and improvement in a capacity retention rate after a rapid charge-discharge cycle.SOLUTION: A negative electrode (60) disclosed herein includes: a negative electrode current collector (62); and a negative electrode active material layer (64) formed on the surface of the negative electrode current collector. The negative electrode active material layer contains silicon oxide containing at least one alkali earth metal. The negative electrode active material layer includes at least a first layer (64A) and a second layer (64B), the first layer being disposed between the second layer and the negative electrode current collector. An amount of the alkali earth metal in the second layer calculated on the basis of, energy dispersive X-ray spectroscopy using a scanning electron microscope image is higher than an amount of the alkali earth metal in the first layer.SELECTED DRAWING: Figure 1 【課題】非水電解質二次電池のサイクル寿命の向上と、急速充放電サイクル後の容量維持率の向上とを両立する負極を提供する。【解決手段】ここに開示される負極（６０）は、負極集電体（６２）と、該負極集電体の表面に形成された負極活物質層（６４）とを備え、前記負極活物質層は、少なくとも一種のアルカリ土類金属を含む酸化ケイ素を含む。前記負極活物質層は、少なくとも第１層（６４Ａ）と第２層（６４Ｂ）とを含み、前記第１層は、前記第２層と前記負極集電体との間に配置されている。ここで、走査型電子顕微鏡画像を用いたエネルギー分散型Ｘ線分析に基づいて算出される前記第２層のアルカリ土類金属量が、前記第１層のアルカリ土類金属量よりも高いことを特徴とする。【選択図】図１