High-performance fiber-shaped Li-ion battery enabled by a surface-reinforced self-supporting electrode.

Herein, we develop a surface-reinforced self-supporting fiber electrode via the simple-yet-reliable ink-extrusion technology to introduce a thin polymer layer at the electrode surface, which endows the fiber architecture with sufficient rigidity for the subsequent fiber cell assembly. Such fiber LiFePO4//Li4Ti5O12 full cells exhibit high linear capacity output (0.144 mA h cm-1) and energy density (0.267 mW h cm-1).