Fig. 3: Electrochemical performance and functional stability of the THBS fibers.

(a) Galvanostatic charge–discharge (GCD) curves of THBS fibers at various current densities. (b) Cyclic voltammograms (CV) curves of THBS fibers at different scan rates, demonstrating stable electrochemical behavior. c Ragone plot combined with in vivo operational duration, comparing THBS fibers with previously reported biocompatible supercapacitors. Stable operation duration is defined as the period during which performance remains within 90–110% of the initial value. Light gray indicates devices with no data or stable operation lasting only 0 days. Black represents devices with stable operation for 1–8 days, while blue indicates devices with stable operation exceeding 9 days. d Capacitance retention of THBS fibers after bending at different angles (30°, 45°, 90°, 120°), as well as twisting (with a bending radius of 1.25 mm) (n = 9 independent samples per group). e Stability of THBS fibers immersed in PBS solution for 20 weeks, illustrating sustained electrochemical performance in physiological environments. f Capacitance retention of THBS fibers after 2000 charge–discharge cycles. g The GCD curves of THBS fibers connected in series and parallel. h Nyquist plots of coin cells before and after thermal treatment. i GCD curves of coin cells before and after thermal treatment. All electrochemical measurements were conducted at room temperature (~25 °C).