fig3

Figure 3. (A) The voltage and current output of the iontronic power source under different external load resistances; (B) Areal Power density output of the power source under different external load resistances; (C) Output voltage curves for different numbers of devices in series; (D) Printing of patterned iontronic power source; (E) The iontronic power supply is connected in series to drive the electronic watch; (F) The power supply is connected in series to drive the calculator; (G) The power source is connected in series to drive the LEDs. LED: Light-emitting diode.