KCS

As the demand for wearable and mobile electronic devices has recently increased, rechargeable lithium-ion batteries (LIBs) have gained tremendous interests. However, since conventional electrode materials in LIBs are obtained through mining, a lack and an uneven geometric distribution of the resources have steeply raised their price. Therefore, it is essential to develop new electrode materials consisting of more abundant elements for next-generation batteries. Here, we report Vat Blue (VB) dyes as a low-cost organic cathode material in batteries. Because the VBs bearing redox-active conjugated carbonyl groups have already been commercialized in dyeing applications, it also has the great potential for a low-cost electrode material. To improve processability of VBs, we introduced thermally cleavable tert-butyloxycarbonyl (t-BOC) groups. In the electrode fabrication process, highly soluble t-Boc-VBs formed homogeneous films with conductive carbon additives and PVDF binder. Subsequently, the drying process spontaneously removed the t-Boc group from the VB molecules to form insoluble active materials in the electrode. Due to low solubility, the electrode showed stable cyclability in coin cells.