A group of researchers from the Tokyo University of Sciences has created biofuel batteries capable of powering different mobile devices using only human sweat. They may be especially useful in the case of portable devices that are used to measure various health-related parameters and that are used in contact with the skin, especially during physical activity.
According to a Press release, the innovation employs a biofuel cell matrix that harnesses a chemical present in human sweat, lactate, thus generating enough energy to drive a biosensor. In this way, it is possible to power wireless communication devices for a short period of time.
The batteries produce electrical energy from the lactate that the sweat of the user of each device possesses, opening the doors to electronic and digital control of health powered only by bodily fluids. In addition to its practicality and economy, this tool will allow you to monitor body performance while playing sports or doing physical activities in a much more sustainable way.
Feeding the biosensors
It is worth noting that although portable electronic devices and biosensors are excellent tools for health monitoring, it has been really very complex until today to find convenient and sustainable energy sources to guarantee their operation. The short duration of the charge of traditional batteries, the related environmental impact and the problems of use in mobility are some of the inconveniences to overcome.
Portable biosensors are small devices that in most cases are designed to be used directly on the skin. In this way they are able to measure specific biological signals, such as heartbeat or blood pressure, sending these measurements wirelessly to smartphones or computers. Thanks to this data it is possible to track the user’s health in real time.
Japanese researchers have developed and tested their new biofuel cell matrix with excellent results, according to the conclusions of a study published in the Journal of Power Sources. The innovation is similar to a paper bandage, which can be easily worn on the arm or forearm. According to specialists, it essentially consists of a water-repellent paper substrate, on which multiple biofuel cells are placed.
How is energy produced? In each cell, the electrochemical reactions between the lactate captured from the user’s sweat and an enzyme present in the electrodes placed in the device generate an electric current, which flows towards a general collector made of conductive carbon paste. Through this mechanism, the energy finally reaches the mobile biosensor and allows its use.
The applications of this new technology seem to have no limits. According to the scientists, the biofuel battery was able to power a commercially available physical activity meter for an hour and a half, using just a drop of sweat.
According to the leader of the research group, Professor Isao Shitanda, “Our experiments confirm that paper-based biofuel cells could generate a voltage of 3.66 V and an output power of 4.3 mW. To our knowledge, this potency is significantly greater than that produced by other previously developed lactate biofuel cells. ‘
In the future, you are batteries they could power a wide variety of wearable devices, such as smart watches.
Paper-based lactate biofuel cell array with high power outputIsao Shitanda, Yukiya Morigayama, Risa Iwashita, Himeka Goto, Tatsuo Aikawa, Tsutomu Mikawa, Yoshinao Hoshi, Masayuki Itagaki, Hiroyuki Matsui, Shizuo Tokito and Seiya Tsujimura. Journal of Power Sources (2021). DOI: https: // doi. org / 10.1016 / j.jpowsour.2021.229533
Photo: Filip Mroz and Unsplash.
Video: Tokyo University of Sciences.
Eddie is an Australian news reporter with over 9 years in the industry and has published on Forbes and tech crunch.