▎ 摘　　要

NOVELTY - Cellulose derivative composition comprises carboxymethyl cellulose derivative (I). USE - Cellulose derivative composition for a secondary battery binder (claimed). ADVANTAGE - The cellulose derivative composition minimizes the formation of the microgels of a cellulose derivative. DETAILED DESCRIPTION - Cellulose derivative composition comprises carboxymethyl cellulose derivative of formula (I). R1, R2 and R3=carboxymethyl group substituted with a monovalent metal (X), a functional group substituted with a monovalent metal (X) and comprising a sulfur (S) element, and comprising a phosphorus (P) element, and hydrogen, where the monovalent metal (X) is among lithium (Li), potassium (K), rubidium (Rb) or cesium (Cs); and ''n''=1 or more. INDEPENDENT CLAIMS are included for the following: 1. a method of preparing a composition for a secondary battery electrode, which involves preparing an aqueous solution comprising a cellulose derivative composition comprising a compound of formula (I), adding an active material to the aqueous solution of the cellulose derivative and stirring to prepare a first slurry, and adding an emulsion to the first slurry and stirring; and 2. a secondary battery comprises a positive electrode, a negative electrode, and an electrolyte layer equipped between the positive electrode and the negative electrode, where the negative electrode comprises a negative electrode active material and a mixture binder, and the mixture binder comprises a cellulose derivative composition.