Improving the cycling stability of lithium-ion batteries with a dry-processed cathode via the synergistic effect of carboxymethyl cellulose and siloxane

The solvent-free dry process for fabricating battery electrodes has received widespread attention owing to its low cost and environmental friendliness. However, the conventional polytetrafluoroethylene (PTFE) used as a binder in the preparation of dry-processed electrodes results in insufficient adhesion, limiting their practical industrial applications. Herein, we reported an industrially viable dry process for producing lithium-ion batteries using the combination of carboxymethyl cellulose (CMC) and siloxane as the binder composite. The synergistic effect of CMC and siloxane enhanced the adhesive performance of the electrode, thereby improving the mechanical strength and electrochemical performance of the developed dry-processed electrode. Half cells based on aluminum-doped lithium manganese oxide (LMA) dry-processed electrodes with CMC and siloxane (LMA/CS) exhibited a capacity retention of 79.8% after 200 cycles at 1 C. Furthermore, LMA/CS∥lithium titanate oxide full cells with a high mass loading of 20.6 mg cm−2 demonstrated an excellent capacity retention of 89.2% after 1000 cycles, which is considerably higher than that of cells based on slurry-processed electrodes prepared with a polyvinylidene fluoride binder and conventional dry-processed electrodes prepared using a PTFE binder.