Whether they contain lead, lithium or cobalt, when batteries are dead the toxic metals usually end up in the environment. In many countries scientists are working to develop clean and simple alternative ways of storing energy. Prof. Dr. Birgit Esser from the Institute of Organic Chemistry at the University of Freiburg and the Cluster of Excellence "Living, Adaptive and Energy-autonomous Materials Systems" (livMatS) is developing a new type of battery which has electrodes made of organic plastics instead of metal. These new energy stores are easier to recycle and so do less harm to the environment than previous products. Metal-free batteries are still in the development phase, but they may soon be found providing a sustainable source of energy in electronic devices.