GelBat: An Edible Gelatin-Based Battery

The development of green batteries has implications for many fields including sustainable robotics and edible electronics. Here we present GelBat, a biodegradable, digestible and rechargeable battery constructed from gelatin and activated carbon. The device utilises the water splitting reaction to produce a simple, sustainable Bacon fuel cell which can produce an output voltage of over 1V for 10 minutes, depending on the load resistance, with 10 minutes of charging and whose only byproduct is water. Electrochemical impedance spectroscopy, cyclic voltammetry and self discharge tests are carried out to characterize the behaviour of the battery. The system does not lose any efficiency with repeated recharging cycles and can be completely dissolved in a simulated gastric fluid within 20 minutes. The simplicity of this design combined with the bioresorbable materials demonstrates the potential of this work to help advance robotic research towards more sustainable untethered autonomous systems and edible robots.