ELECTRODE FOR SECONDARY BATTERY, SECONDARY BATTERY, BATTERY PACK, ELECTRIC VEHICLE, ELECTRIC POWER STORAGE SYSTEM, ELECTRIC POWER TOOL, AND ELECTRONIC APPARATUS

摘要

PROBLEM TO BE SOLVED: To provide a secondary battery that can achieve excellent battery characteristics.SOLUTION: A positive electrode includes a second lithium-containing compound having an olivine-type crystal structure. A photoelectron spectrum of oxygen 1s obtained by surface analysis of the positive electrode with the use of X-ray photoelectron spectroscopy includes: a third peak having an apex in a range in which binding energy is 530 eV or more and less than 533 eV; and a fourth peak having an apex in a range in which binding energy is 533 eV or more and 536 eV or less and having spectrum intensity smaller than that of the third peak. A ratio IE/ID between a spectrum intensity ID of the third peak and a spectrum intensity IE of the fourth peak is larger than 1/4.