Abstract: The slurry for forming negative electrode active material layer of the present disclosure contains: a ketone as a dispersion medium; and silicon active material particles, sulfide solid electrolyte particles, and single-wall carbon nanotubes, which are dispersed in the ketone, and a ratio of the single-wall carbon nanotubes with respect to the ketone is 0.15% by mass or lower.

Abstract: The present disclosure has an object of providing an electrode active material composite particle having a small expansion due to charging, a solid-state battery comprising such an electrode active material composite particle, a method for manufacturing such an electrode active material composite particle, and a method for manufacturing a solid-state battery comprising manufacturing such an electrode active material composite particle. The electrode active material composite particle of the present disclosure comprises a silicon particle and a fibrous conductive material. In the electrode active material composite particle of the present disclosure, the fibrous conductive material is localized inside the electrode active material composite particle.

Abstract: The negative electrode active material layer of the present disclosure contains: silicon active material particles; sulfide solid electrolyte particles; and multi-wall carbon nanotubes, and this negative electrode active material layer has, on average, one or more planar cracks having a length of 10 ?m or more in regions of 50 ?m in thickness direction×50 ?m in width direction at a cross-section.

Abstract: An object of the present disclosure is to provide a negative electrode active material layer, in which electrical conductivity of silicon active material particles is improved by decreasing the amount of oxygen atoms in the silicon active material particles while electrical resistance is less likely to deteriorate even when charging capacity of a battery is low, and a solid-state secondary battery comprising such a negative electrode active material layer. The negative electrode active material layer of the present disclosure contains silicon active material particles and solid electrolyte particles, wherein an amount of oxygen atoms in the silicon active material particles is less than 5.0% by mass, and an average particle size of the solid electrolyte particles is 1.0 ?m or less and/or a ratio of an average particle size of the solid electrolyte particles relative to an average particle size of the silicon active material particles is 0.9 or less.

Abstract: A binder composition includes a dispersion medium and a group of binder particles. The group of binder particles is dispersed in the dispersion medium. The group of binder particles include a polymer material. The polymer material includes a constitutional unit originated from vinylidene difluoride. The group of binder particles has a number-based particle size distribution. The particle size distribution satisfies the following conditions: “0.19?X?0.26”, “0.69?Y?0.76”, and “0?Z?0.05”. Here, “X” represents a frequency of particles each having a particle size of less than or equal to 40 ?m. “Y” indicates a frequency of particles each having a particle size of more than 40 ?m and less than or equal to 110 ?m. “Z” indicates a frequency of particles each having a particle size of more than 110 ?m and less than or equal to 250 ?m.

Abstract: A composite particle includes a positive electrode active material particle and a coating film. In a method for producing the composite particle, the coating film covers at least a part of a surface of the positive electrode active material particle, the coating film contains a phosphorus compound, and a glass-transition temperature of the coating film is 300° C. or less.

Abstract: A binder composition includes a dispersion medium and a group of binder particles. The group of binder particles is dispersed in the dispersion medium. The group of binder particles include a polymer material. The polymer material includes a constitutional unit originated from vinylidene difluoride. The group of binder particles has a number-based particle size distribution. The particle size distribution satisfies the following conditions: “0.19?X?0.26”, “0.69?Y?0.76”, and “0?Z?0.05”. Here, “X” represents a frequency of particles each having a particle size of less than or equal to 40 ?m. “Y” indicates a frequency of particles each having a particle size of more than 40 ?m and less than or equal to 110 ?m. “Z” indicates a frequency of particles each having a particle size of more than 110 ?m and less than or equal to 250 ?m.