Imagine you are working out, and your fitness tracker runs out of battery. Or you are on your morning walk, and your smartwatch shows a low battery notification. With wearable devices becoming a part of our daily lives, the frustration of remembering to charge them is real.
What if we told you that your smart device can now self-charge and will never run out of battery? Also, it will use your sweat to charge itself. Sounds like a sci-fi movie? Well, it’s closer to reality.
Researchers at the University of Massachusetts Amherst have developed a skin-patch-like biofilm that uses sweat to generate electricity and power devices.
Let’s know more about this biofilm in detail.
Biofilm powering smart devices with sweat
While the research to generate electricity using bacterial biofilm is nothing new, researchers at UMass Amherst have added a new spectrum to it. Their biofilm is specially designed to stick to the skin like a band-aid and utilise sweat to power devices.
This newly developed biofilm has the potential to revolutionise the wearable technology market, powering everything from personal medical sensors to personal electronics.
How does the biofilm work?
The biofilm is a sheet of bacterial cells as thin as a paper sheet. It is produced naturally by an engineered version of Geobacter sulfurreducens, bacteria known to produce electricity. The G. sulfurreducens bacteria have previously been used in ‘microbial batteries’ to power electrical devices.
These G. Sulfurreducens grow in colonies that look like thin mats, and each bacteria connects to its neighbour through a series of ‘natural nanowires’. These mats are harvested, and small circuits are etched into them using a laser. Then, they’re sandwiched between electrodes and finally sealed in a soft, sticky, breathable polymer that can be applied directly to the skin.
As the surface of our skin is constantly moist with sweat, the biofilm plugs in and converts the energy locked in evaporation into electrical energy to power small devices.
The entire process relies on evaporation-based electricity production—the hydrovolcanic effect. Here, water flow is driven by evaporation between solid biofilm and liquid water, which drives the transport of electrical charges to generate an electrical current.
What makes this biofilm different?
- Made of dead bacteria
Previous research has looked into the potential of other microbes to generate electricity where keeping the bacteria alive and providing them with food and a suitable environment have been major bottlenecks. However, the biofilm developed by the UMass Amherst research team is from dead bacteria. G. Sulfurreducens need not be alive to generate electricity. This makes the biofilm unique.
- Green and efficient
Another factor that makes it different from its competitors is it is real green energy. Sustainable and efficient.
“It’s much more efficient. We’ve simplified the process of generating electricity by radically cutting back on the amount of processing needed. We sustainably grow the cells in a biofilm, and then use that agglomeration of cells. This cuts the energy inputs and makes everything simpler.”
– Derek Lovley, study author, said in a statement.
- Works on both sweaty and non-sweaty skin!
One common question that arose during its research was—How will it work on sweaty and non-sweaty skin?
During the 30 days lab test, the biofilm generated electricity on sweaty skin even after 18 hours. Even on non-sweating skin, it generated a substantial electric output. This shows that a continuous low-level secretion of moisture from the skin is sufficient to drive its hydroelectric output.
Its features and steady performance make it a promising candidate for the continuous powering of wearable electronics.
Future goals with this biofilm
The biofilm now produces enough energy to power small devices like medical sensors. The team hopes to produce even more significant amounts of energy on a larger scale to power an entire electronic system and not just a single device.
They envision using their biofilm to make better use of the untapped energy from evaporation, citing research that suggests that approximately 50% of the solar energy reaching earth is spent on evaporation.
Biofilm-powered devices might be the future
The pandemic has increased health awareness around the globe, resulting in a significant rise in demand for wearable tech. However, bulky, heavy and uncomfortable batteries that need to be constantly charged or changed are a potential drawback.
Considering the numerous positive reviews the biofilm has received, there is a high chance wearable tech companies will start incorporating it for sleek design and user comfort. However, the true potential of the biofilm is unknown, as it is still ongoing research. We can only wait to see what innovation it brings to the healthcare industry.
What do you think? Let us know in the comments.
