Researchers at the University of California San Diego and Toyota Research Institute of North America developed a fluorine-free, water-processable binder for lithium-ion battery electrodes. The peer-reviewed study, published in Nature Communications on October 9, makes the material by crosslinking polyacrylic acid and carboxymethyl cellulose with citric acid. Laboratory lithium iron phosphate electrodes made with the binder showed initial capacity comparable to control electrodes using conventional PVDF binder, with better cycle stability.

The authors report compatibility with several positive and negative electrode materials. Soaking spent electrodes in water dissolved the binder and separated the coatings from metal foil without residue; recovered materials were then used in direct-recycling steps to build cells again. The paper’s life-cycle analysis estimates lower energy cost and emissions than recycling PVDF-based batteries, without stating a numerical reduction in the article summary. This is a laboratory demonstration. The team says it will next adapt the binder to different battery chemistries and work on scaling production.