POWER STORAGE DEVICE BINDER COMPOSITION, POWER STORAGE DEVICE ELECTRODE SLURRY, POWER STORAGE DEVICE ELECTRODE, AND POWER STORAGE DEVICE

Provided is a binder composition for an electrical storage device, which enables the production of an electrical storage device electrode excellent in repeated charge-discharge characteristic through a reduction in internal resistance and also excellent in charge-discharge durability characteristic under high temperature through an improvement in adhesiveness. The binder composition for an electrical storage device includes: a polymer (A); and a liquid medium (B), wherein, with respect to 100 mass % in total of repeating units contained in the polymer (A), the polymer (A) contains: 15 mass % to 60 mass % of a repeating unit (a1) derived from a conjugated diene compound; and 1 mass % to 10 mass % of a repeating unit (a2) derived from an unsaturated carboxylic acid, wherein tan δ (loss elastic modulus/storage elastic modulus) in dynamic viscoelasticity of the polymer (A) has one peak top in a range of from −40° C. or more to less than 50° C., and has one peak top in a range of from 50° C. or more to 150° C. or less, and wherein, when the tan δ at the peak top in the range of from −40° C. or more to less than 50° C. is represented by tan δ(Tp1), and the tan δ at the peak top in the range of from 50° C. or more to 150° C. or less is represented by tan δ(Tp2), a relationship of the following expression (1) is satisfied. tan δ(2)/tan δ(1)≥0.5 (1)