Table 2. Comparison of power management technologies for wearable and implanTable applications

Device type	Applicability	Rationale
Battery	Wearable	High energy density and sTable output.Repeated surgical interventions required for battery replacement.Limited long-term safety due to electrolyte leakage.
PV	Wearable	High energy density under sufficient light illumination.Strong dependence on light exposure.
BFC	Wearable & Implantable	Continuous power generation from body fluids.
TEG	Wearable	Continuous power generation from the temperature gradient between the body and the environment.Low power density due to limited temperature gradient when implanted.
PENG	Wearable & Implantable	Power generation from mechanical stimuli, such as heartbeat, breathing, and muscle contraction-relaxation.
TENG	Wearable & Implantable	High output voltage through contact electrification and electrostatic induction.
WPT	Wearable & Implantable	Long-term, battery-free wireless power transfer.