SBIR Phase II: Environmentally Compatible Recycling Method for Cadmium Telluride Devices

Interphases Solar, Inc., Moorpark CA

Investigators

Abstract

This Small Business Innovation Research (SBIR) Phase II project will develop an electrochemical method specific to recycling photovoltaic modules, which contain extremely low quantities of hazardous metals in large bulk-streams. It uses an innovative closed-loop approach to remove, separate, and regenerate semiconductor films in a single compact system, and do it with minimum waste. Phase I identified key process parameters, focusing on efficient removal and recovery of semiconductors from devices. Retrieval of sulfur-free cadmium telluride demonstrated method feasibility. Phase II will design a practical system to recycle the entire module for in-plant or centralized applications. It will identify the optimum parameters to delaminate modules, dissolve semiconductors, regenerate useful semiconductor precursor films, and re-utilize the electrolyte. The research will lead to a viable prototype recycling capability featuring low cost, high efficiency, low cycle-time, and production line amenability. Converting defective panels into efficient modules will lead to rapid turn-around and high production yields. Potential commercial applications are expected in the photovoltaic industry with a solution to managing hazardous waste disposal and improvement in module production yield. It has short-term applications for recycling other end-of-life products such as flat panel displays, infrared detectors, and mirror scrap. Benefits are anticipated in increased productivity, large savings in disposal costs, recovery of scarce raw materials, and enhanced commercial success of the emerging cadmium telluride photovoltaic industry, which has grown 50-fold in production capacity within two years.