Electrode mixture, secondary battery, and composition

An electrode mixture comprising:

• an electrode active material;
• an organic solvent;
• a binder;
• and an additive, wherein
• the binder comprises a fluorine-containing copolymer comprising a vinylidene fluoride unit and a fluorinated monomer unit, provided that the vinylidene fluoride unit is excluded from the fluorinated monomer unit;
• and a polyvinylidene fluoride,
• the additive is a polymer material containing the following repeating unit:
• —[CH2—CHR]—
• wherein R represents a chain or cyclic amide group, a nitrile group, or a substituted alkyl group formed by substituting at least one of hydrogen atoms of an alkyl group having 1 to 4 carbon atoms with a chain or cyclic amide group or a nitrile group,
• a content of the binder is 0.1 to 1.6 parts by mass with respect to 100 parts by mass of the electrode active material,
• a content of the additive is 0.001 to 0.2 parts by mass with respect to 100 parts by mass of the electrode active material,
• a content of the vinylidene fluoride unit in the fluorine-containing copolymer is 50.0 to 99.0 mol % with respect to all monomer units, and
• a content of vinylidene fluoride unit in the polyvinylidene fluoride is more than 99.0 mol % with respect to all monomer units.