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

Provided are a binder aqueous solution for a lithium-ion battery electrode, a slurry for a lithium-ion battery negative electrode, a negative electrode for a lithium-ion battery, and a lithium-ion battery. The binder aqueous solution for a lithium-ion battery electrode contains an acidic group-containing water-soluble polymer (A) and an amino group-containing water-soluble polymer (B). The acidic group-containing water-soluble polymer (A) is a polymer of a monomer group containing, with respect to 100 mol% of the monomer group, 30 mol% to 90 mol% of a (meth)acrylamide group-containing compound (a), 3 mol% to 20 mol% of an unsaturated organic acid (b), and 5 mol% to 40 mol% of an alkali metal or alkaline earth metal salt (c) of the unsaturated organic acid. A 1% by mass aqueous solution of the amino group-containing water-soluble polymer (B) has a pH of 9 or higher.