The idea of harvesting green energy from everyday wetness to power wearables and portable electronics is gaining traction. Fabricating high-performing moisture-electric generators (MEG) with high and stable output remains a challenge.
Strategic Element, an Australian startup, has teamed up with the University of New South Wales and the CSIRO to develop a flexible, self-charging battery that harvests electricity from humidity in the air or on the skin surface and charges itself in under a minute. These batteries can power electronics and Internet of Things (IoT) devices directly.
This technique has the potential to allow batteries to self-charge by absorbing moisture from the air, eliminating the need for human charging or cable electricity. The research will provide new electronic materials for a variety of applications in flexible electronics, as well as substantial advancements in energy-efficient data storage systems.
Most high-performance MEGs are currently made with carbon-based materials, such as carbon nanotubes, carbon nanoparticles, and graphene oxide, which are both environmentally friendly and abundant on the planet. Because of its high specific surface area, outstanding mechanical qualities, and great moisture absorption, graphene oxide has the most promising potential for producing high electric generation.
Graphene-based materials can gather energy from environmental elements such as moisture and heat thanks to their outstanding physicochemical features. The oxidation of graphite, which is inexpensive and abundantly available, produces graphene oxide.
Researchers created MEGs out of porous graphene oxide treated with hydrochloric acid for their study, which had a high moisture absorption ability. The MEG that results allows for a stable voltage of 0.85 V and a current of 9.28 A (92.8 A per square centimeter), which is “among the highest levels reported so far.” More curiously, merely connecting four MEG devices in series or parallel improves the electric output.
The researchers built a battery on a piece of carbon cloth and bent it from 0 to 120 degrees in one second to evaluate its flexibility. After 2000 bends, the flexible MEG maintained 93 percent of its maximum voltage, indicating that it has a lot of potential in flexible and wearable applications.
Additional technological hurdles include expanding battery cell size while increasing current output at lower humidity levels, as well as developing demonstrator devices.