POSITIVE ELECTRODE MATERIAL FOR SECONDARY BATTERIES, METHOD FOR PRODUCING POSITIVE ELECTRODE MATERIAL FOR SECONDARY BATTERIES, AND SECONDARY BATTERY

摘要

The present invention provides a positive electrode material for Li ion secondary batteries having high output and high energy density, which has excellent electron conductivity and Li ion conductivity, and is capable of suppressing side reactions such as oxidative decomposition of an electrolyte solution and dissolution of a transition metal component in the positive electrode material into the electrolyte solution when a high voltage is applied during charging. A positive electrode material for secondary batteries according to the present invention is characterized in that the surfaces of primary particles of an electrode active material base containing Li are covered with a layer that contains a conductive polymer and negative ions which enable the conductive polymer to produce electron conductivity equal to or higher than the electron conductivity of the electrode active material itself, said electrode active material base being capable of electrode oxidation reduction accompanied by desorption and absorption of Li ions in the potential range from 4V to 5V (inclusive) based on a Li metal negative electrode and having a reversible charge/discharge capacity accompanying the electrode oxidation reduction in the above-described potential range of 30 mAh or more per 1 g.