To improve the low efficiency of retired power battery recycling caused by information asymmetry, low trust, and channel competition, this paper develops a two-level closed-loop supply chain model including a power battery supplier and an electric vehicle manufacturer. Both firms recycle batteries in parallel and compete with each other. A blockchainbased traceability level is introduced to show how better information transparency affects market demand and recycling quantity. Blockchain investment cost and platform access fee are also considered. Under Stackelberg game and centralized decision-making, four scenarios are studied: no blockchain with separate recycling, no blockchain with cooperative recycling, blockchain with separate recycling, and blockchain with cooperative recycling. Equilibrium solutions are derived by backward induction, and comparative analysis and numerical experiments are conducted. The results show that cooperative recycling can reduce double marginalization and ease inefficient competition, thus improving supply chain performance. Blockchain adoption increases the optimal traceability level, market demand, and recycling quantity, which further improves total profit. The proposed model also provides strategic insights for the closed-loop management of emerging smart textile energy systems. The best outcome appears when cooperative recycling and blockchain are used together. Numerical results also show that stronger blockchain market effects increase these benefits, while higher blockchain cost reduces traceability investment and makes profits closer to the no-blockchain case.

retired power batteries, closed-loop supply chain, blockchain traceability, stackelberg game