The copolymer described is a segmented copolymer consisting essentially of organic segments A which have a number i of reactive ends such that i is from 1 to 6 inclusive, and segments B which have a number j of reactive ends such that j is from 1 to 6 inclusive. The segments B have redox properties and each segment A is connected to at least one segment B by a group Y and vice versa, the group Y being an ether, thioether, secondary amine, tertiary amine, secondary amide, tertiary amide, imide, quaternary ammonium group, or a group having a carbon-carbon bond. The respective weighted molar mean of i and j is 2 or more. Application to electrochemical generators and electrochromic systems.