▎ 摘　　要

NOVELTY - A composite material comprises graphene which is loaded on graphene sheet layer of bismuth oxide. The mass ratio of bismuth oxide and graphene is 0.005-0.25:1. USE - Composite material is used for preparing lead-carbon battery paste for lead-carbon battery negative electrode plate (all claimed) for supercapacitor battery. ADVANTAGE - The supercapacitor battery comprising the composite material has excellent durability and favorable electric current efficiency. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) lead-carbon battery paste, which comprises 100 parts mass lead powder, 4-100 parts mass sulfuric acid, 0.1-8 parts mass binder, 0.1-2 parts mass barium sulfate, 1-10 parts mass composite material, 1-4 parts mass humic acid, 5-15 parts mass red lead, 12-21 parts mass water, and 0.1-0.2 parts mass short fiber; (2) preparation of graphene oxide composite material; and (3) preparation of lead-carbon battery paste.