BINDER COMPOSITION FOR POWER STORAGE DEVICE, SLURRY FOR POWER STORAGE DEVICE ELECTRODE, 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 charge-discharge durability characteristic under high temperature by improving adhesiveness under high temperature and reducing internal resistance thereunder. The binder composition for an electrical storage device includes: a polymer (A) and a liquid medium (B), wherein, with respect to 100 parts by mass in total of repeating units contained in the polymer (A), the polymer (A) contains: 15 parts by mass to 60 parts by mass of a repeating unit (a1) derived from a conjugated diene compound; 35 parts by mass to 75 parts by mass of a repeating unit (a2) derived from an aromatic vinyl compound; and 1 part by mass to 10 parts by mass of a repeating unit (a3) derived from an unsaturated carboxylic acid, and wherein, when, in dynamic viscoelasticity measurement of the polymer (A), a peak top of tanδ (loss elastic modulus/storage elastic modulus) is represented by tanδ(Tp), and tanδ at 100°C is represented by tanδ(100°C), a relationship of the following expression (1) is satisfied. tanδ(100°C)/tanδ(Tp)×100≤10 (1)