Provided are a polyimide binder for energy storage device capable of improving properties of an energy storage device in a broad temperature range, and an electrode sheet and an energy storage device using the same. The polyimide binder for energy storage device, which is a polyimide obtained by subjecting an aqueous solution of a polyamic acid composed of a repeating unit represented by the following general formula (I) to an imidization reaction, the polyimide having a tensile elastic modulus of 1.5 GPa or more and 2.7 GPa or less.
In the formula, A is a tetravalent group resulting from eliminating a carboxyl group from a specified tetracarboxylic acid, and B is a divalent group resulting from eliminating an amino group from a specified diamine, provided that 55 mol % or more of B in a total amount of the repeating unit is the divalent group resulting from eliminating an amino group from an aliphatic diamine having a molecular weight of 500 or less.