Cathode material for secondary batteries, method for producing cathode material for secondary batteries, and secondary battery

A cathode material for secondary batteries comprising;

• an electrode active material base containing Li, wherein
• the electrode active material base is capable of an electrode oxidation/reduction accompanied by desorption and absorption of Li ions in a potential range of 4 V or more and 5 V or less based on a metal Li negative electrode and has a reversible charge/discharge capacity accompanying the electrode oxidation/reduction in the potential range described above of 30 mAh or more per 1 g, and
• surfaces of primary particles of the electrode active material base are coated with a layer containing a conductive polymer.

A method for producing a cathode material for secondary batteries characterized by including the steps of:

• oxidizing a part of an electrode active material by bringing a solution in which an oxidant that has oxidation power capable of at least partially oxidizing the electrode active material and capable of oxidizing and polymerizing a monomer or an oligomer to be a raw material of a conductive polymer is dissolved into contact with an entire surface of the electrode active material containing Li, which is capable of electrode oxidation/reduction accompanied by desorption and absorption of Li ions in a potential range of 4 V or more and 5 V or less based on a metal Li negative electrode and has a reversible charge/discharge capacity accompanying the electrode oxidation/reduction in the potential range described above of 30 mAh or more per 1 g;
• and
• thereafter, coating surfaces of primary particles of the electrode active material with a layer that contains the conductive polymer and a negative ion by oxidizing and polymerizing the monomer or oligomer while doping the negative ion by bringing a solution in which the monomer or oligomer and the negative ion are dissolved into contact with the entire surface of the electrode active material.

A method for producing a cathode material for secondary batteries characterized by including the steps of:

• allowing an entire surface of an electrode active material to adsorb a monomer or oligomer by bringing a solution in which the monomer or oligomer to be a raw material of a conductive polymer is dissolved into contact with an entire surface of the electrode active material containing Li, which is capable of electrode oxidation/reduction accompanied by desorption and absorption of Li ions in a potential range of 4 V or more and 5 V or less based on a metal Li negative electrode and has a reversible charge/discharge capacity accompanying the electrode oxidation/reduction in the potential range described above of 30 mAh or more per 1 g;
• and,
• thereafter, coating surfaces of primary particles of the electrode active material with a layer containing the conductive polymer and a negative ion by oxidizing and polymerizing the monomer or oligomer while doping the negative ion by bringing a solution in which an oxidant having oxidizing power capable of oxidizing and polymerizing the monomer or oligomer and the negative ion that enable the conductive polymer to produce electron conductivity equal to or higher than the electron conductivity of the electrode active material itself are dissolved into contact with the entire surface of the electrode active material.

A method for producing a cathode material for secondary batteries characterized by including the steps of:

• oxidizing a part of an electrode active material by bringing an oxidant that has oxidation power capable of at least partially oxidizing the electrode active material and capable of oxidizing and polymerizing a monomer or an oligomer to be a raw material of a conductive polymer or a solution in which the oxidant is dissolved into contact with an entire surface of the electrode active material containing Li, which is capable of electrode oxidation/reduction accompanied by desorption and absorption of Li ions in a potential range of 4 V or more and 5 V or less based on a metal Li negative electrode and has a reversible charge/discharge capacity accompanying the electrode oxidation/reduction in the potential range described above of 30 mAh or more per 1 g;
• and,
• thereafter, coating surfaces of primary particles of the electrode active material with a layer that contains the conductive polymer by oxidizing and polymerizing the monomer or oligomer by bringing a solution in which any one of the monomer or oligomer or the monomer and oligomer are dissolved into contact with the entire surface of the electrode active material.

A method for producing a cathode material for secondary batteries characterized by including the steps of:

• allowing an entire surface of an electrode active material to adsorb a monomer or oligomer by bringing a solution in which the monomer or oligomer, or the monomer and oligomer to be a raw material of a conductive polymer are dissolved into contact with an entire surface of the electrode active material containing Li, which is capable of electrode oxidation/reduction accompanied by desorption and absorption of Li ions in a potential range of 4 V or more and 5 V or less based on a metal Li negative electrode and has a reversible charge/discharge capacity accompanying the electrode oxidation/reduction in the potential range described above of 30 mAh or more per 1 g;
• and,
• thereafter, coating surfaces of primary particles of the electrode active material with a layer containing the conductive polymer by oxidizing and polymerizing the monomer or oligomer by bringing an oxidant having oxidizing power capable of oxidizing and polymerizing the monomer or oligomer or a solution in which the oxidant is dissolved into contact with the entire surface of the electrode active material.