▎ 摘　　要

NOVELTY - The system has a vacuum cover plate arranged on a side of a heat insulation box. A multi-level heat accumulation unit is connected with a carbon-based composite phase change material with different phase change temperature. A temperature control system is used for collecting temperature of the multi-level heat accumulation unit when collected temperature is lower than preset temperature. The temperature control system supplies power to the carbon-based composite phase change material in the multi-level heat accumulation unit. The phase change material is made of carbon-based support matrix, graphite, carbon fiber, and conductive carbon black. The graphite is a crystalline flake graphite, a microcrystalline graphite, a nano-graphite, and a graphene. The carbon fiber is an active carbon fiber and asphalt carbon fiber. The phase change material is made of paraffin wax type, fatty acid, alcohol high polymer. The vacuum cover plate is made of PVC, and acrylic board polycarbonate. USE - Light/electricity-heat self-conversion multi-stage phase change heat accumulation system. ADVANTAGE - The carbon-based composite phase change material can generate electric heating self-conversion without an external heating component. A pipeline of a structure can improve heat conversion efficiency. The system forms a complementary mechanism that integrates optical/electrical-thermal conversion with thermal energy storage/release. The system solves a problem of high cost. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic diagram of a light/electricity-heat self-conversion multi-stage phase change heat accumulation system. 1Vacuum cover plate 2Carbon-based composite phase change material 3Copper foil electrode 4Water outlet 5Water inlet 6Pipeline 7Heat insulation box 8Container 9Temperature control system