Flexible single-walled carbon nanotube/polycellulose papers for lithium-ion batteries

Flexible and highly conductive single-walled carbon nanotube/polycellulose papers (SWCNT/PPs) were developed as current collectors for lithium-ion batteries by a simple and scalable process. The flexible electrodes based on SWCNT/PP conductors consisted of a unique three-dimensional interwoven structure of electrode materials and cellulose fibers with CNTs and exhibited flexibility, good electrochemical performance and excellent cyclic stability. Full cells using Li₄Ti₅O₁₂ and LiFePO ₄ electrodes based on SWCNT/PPs showed a first discharge capacity of 153.5 mA h g^-1 with Coulombic efficiencies of 90.6% at 0.1 C and discharge capacity of 102.6 mA h g^-1 at high rate (10 C). Full cells based SWCNT/PP conductors showed higher capacities and lower electrochemical interfacial resistance compared to metallic current collectors. Half cells using anatase TiO₂ hierarchical spheres based on SWCNT/PP conductors also exhibited outstanding electrochemical performance, verifying the stability of SWCNT/PP conductors to various electrode materials. Our results demonstrated the potential versatility of composite electrodes and conductive SWCNT/PPs for flexible and portable micropower devices.