Binder composition for all-solid-state secondary battery, slurry composition for all-solid-state secondary battery, solid electrolyte-containing layer, and all-solid-state secondary battery
Provided is a binder composition with which it is possible to produce a slurry composition having excellent dispersibility and to form a solid electrolyte-containing layer that can cause an all-solid-state secondary battery to display excellent cycle characteristics. The binder composition contains a polymer and an aromatic halide. The polymer includes a nitrile group-containing monomer unit in a proportion of 10 mass % to 35 mass % and a (meth)acrylic acid ester monomer unit in a proportion of 15 mass % to 40 mass %. The aromatic halide has a structure in which not less than 2 and not more than 4 halogen atoms are bonded directly to an aromatic ring, and the content of the aromatic halide in the binder composition is 5 mass ppm to 3,000 mass ppm relative to the content of the polymer.
1 . A slurry composition for an all-solid-state secondary battery comprising:
a solid electrolyte; and
a binder composition comprising a polymer, an aromatic halide, and a solvent, wherein
the polymer includes a nitrile group-containing monomer unit in a proportion of not less than 10 mass % and not more than 35 mass % and a (meth) acrylic acid ester monomer unit in a proportion of not less than 15 mass % and not more than 40 mass %,
the aromatic halide has a structure in which not less than 2 and not more than 4 halogen atoms are bonded directly to an aromatic ring, and
content of the aromatic halide is not less than 5 mass ppm and not more than 3,000 mass ppm relative to content of the polymer.
2 . The slurry composition for an all-solid-state secondary battery according to claim 1 , wherein the binder composition further comprises a metal belonging to period 5 of the periodic table and belonging to groups 3 to 14 of the periodic table in an amount of not less than 0.5 mass ppm and not more than 200 mass ppm relative to the content of the polymer.
3 . The slurry composition for an all-solid-state secondary battery according to claim 1 , wherein the binder composition further comprises a metal belonging to group 1 or group 2 of the periodic table in an amount of not less than 5 mass ppm and not more than 3,000 mass ppm relative to the content of the polymer.
4 . The slurry composition for an all-solid-state secondary battery according to claim 1 , wherein the polymer has an iodine value of not less than 0.5 mg/100 mg and not more than 20 mg/100 mg.
5 . The slurry composition for an all-solid-state secondary battery according to claim 1 , wherein a number of carbon atoms forming an alkyl group that is bonded to a non-carbonyl oxygen atom in the (meth) acrylic acid ester monomer unit is not less than 4 and not more than 9.
6 . The slurry composition for an all-solid-state secondary battery according to claim 1 , further comprising an electrode active material.
7 . The slurry composition for an all-solid-state secondary battery according to claim 6 , further comprising carbon nanotubes.
8 . A solid electrolyte-containing layer formed using the slurry composition for an all-solid-state secondary battery according to claim 1 .
9 . An all-solid-state secondary battery comprising the solid electrolyte-containing layer according to claim 8 .