POSITIVE ELECTRODE ACTIVE MATERIAL AND LITHIUM SECONDARY BATTERY USING THE SAME

• Main Author: TSUJIKO AKIRA
• Format: Patent
• Language: English; Japanese
• Published: 16.08.2018
• 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 positive electrode active material that has improved stability in which elution of manganese is suppressed better.SOLUTION: There is provided a positive electrode active material for a lithium secondary battery containing a lithium-manganese composite oxide having a spinel structure. In the lithium manganese complex oxide, a ratio (A/B) of the peak intensity A at 654 eV at the Mn-L absorption edge to the peak intensity B at 537.5 eV at the OK absorption edge satisfies 0<(A/B)≤0.2, which are measured by X-ray absorption microstructure analysis (XAFS) based on the all-electron yield method.SELECTED DRAWING: Figure 2 【課題】マンガンの溶出がより良く抑制され、安定性の向上した正極活物質を提供すること。【解決手段】本発明により、スピネル構造を有するリチウムマンガン複合酸化物を含んだリチウム二次電池用の正極活物質が提供される。上記リチウムマンガン複合酸化物は、全電子収量法に基づくＸ線吸収微細構造解析（ＸＡＦＳ）で測定される、Ｍｎ−Ｌ吸収端の６５４ｅＶにおけるピーク強度Ａと、Ｏ−Ｋ吸収端の５３７．５ｅＶにおけるピーク強度Ｂとの比（Ａ／Ｂ）が、０＜（Ａ／Ｂ）≦０．２を満たす。【選択図】図２