Hybrid biopolymer electrodes for lithium- and sodium-ion batteries in organic electrolytes

The use of earth abundant and renewable materials is encouraging for the future development of environmentally clean, safe and affordable electrodes for lithium- and sodium-ion batteries. Biohybrid electrodes based on lignin and several conducting polymers have been studied mainly for supercapacitor applications. Here, we show that biohybrid electrodes containing natural lignin and a PEDOT conjugated polymer serve as electroactive materials for lithium- and sodium-ion batteries using liquid organic electrolytes. A reversible discharge capacity of 74 mA h g−1, at C/20 (4 mA g−1) rate, was achieved in the voltage range between 1 V and 4.5 V, with peak values of up to 159 mA h g−1. These properties make the natural lignin–PEDOT hybrid material a suitable organic positive electrode for Li- and Na-ion batteries