BINDER AQUEOUS SOLUTION FOR LITHIUM-ION BATTERY ELECTRODE, SLURRY FOR LITHIUM-ION BATTERY ELECTRODE, LITHIUM-ION BATTERY ELECTRODE, AND LITHIUM-ION BATTERY

Provided are a binder aqueous solution for a lithium-ion battery electrode, a slurry for a lithium-ion battery electrode, a lithium-ion battery electrode, and a lithium-ion battery. The binder aqueous solution for a lithium-ion battery electrode contains a water-soluble polymer (A). The water-soluble polymer (A) is a polymer of a monomer group containing, with respect to 100 mol % of the monomer group, 5 mol % to 80 mol % of a hydroxyl group-containing vinyl ether (a). In one embodiment, the monomer group contains 20 mol % to 95 mol % of a (meth)acrylamide group-containing compound (b).