New Technology: Ultra-Thin Film Using Body Heat To Power Wearable Devices

       A new development in flexible thermoelectric film technology may pave the way for a new generation of wearable devices and cooling solutions. Researchers from Queensland University of Science and Technology (QUT) have created a flexible film, which solves the long-standing problems in flexibility, manufacturability and performance.

Australian researchers have designed an ultra-thin flexible film that can use human body heat to power wearable devices, thus eliminating the need for batteries. This technology can also cool the electronic chips in smartphones and computers, marking significant progress in this field, which has been developing steadily for many years. This breakthrough is based on the basic work done by the global research team focusing on energy collection and thermal management.

For a long time, the thermoelectric equipment that can convert the temperature difference into electric energy has been the pursuit of wearable electronic devices. However, it is difficult to produce a flexible, efficient and commercially viable version. Limited flexibility, complex manufacturing process, high cost and insufficient performance have always been obstacles to the scale and commercialization of flexible inorganic thermoelectric semiconductor devices in wearable electronic devices and high-end cooling applications.

Professor Chen Zhigang of Queensland University of Science and Technology and his team seem to have solved these problems. Their research results were published in the journal Science, introducing a cost-effective technology for producing flexible thermoelectric films. The key to innovation is to use tiny crystals or "nano binders" to form a consistent layer of bismuth telluride film, thereby improving efficiency and flexibility.

The research team's method integrates solvothermal synthesis, screen printing and sintering technologies. Solvothermal synthesis is to generate nanocrystals in solvent under high temperature and pressure, while screen printing can produce films on a large scale. The sintering process heats the film to near the melting point, effectively bonding the particles together.

The resulting printable film consists of Bi ₂ Te ≮ based nanoplates as highly oriented grains and Te nanorods as nano binders. When assembled into flexible thermoelectric equipment, the power density of the film is among the best in screen printing equipment.

The Queensland University of Technology team's approach is not limited to thermoelectric technology based on bismuth telluride. Wenyi Chen, the first author of the study, pointed out that their technology can also be used in other systems, such as silver selenide thermoelectric systems, which may be cheaper and more sustainable.

This technology has opened up a series of potential applications. Professor Chen said: "The flexible thermoelectric device can be comfortably worn on the skin, effectively converting the temperature difference between the human body and the surrounding air into electrical energy."

In addition to powering wearable electronic devices, this film can also be used for personal thermal management. For example, the integration of flexible thermoelectric devices into textiles opens up new possibilities for smart clothing, which can be used to manufacture self powered heating clothing for cold environments.

Early research shows that flexible thermoelectric semiconductor devices can provide innovative solutions for energy collection and thermal management in all walks of life. In the automotive industry, flexible thermoelectric devices can be integrated into the vehicle to power the battery free distance detection sensor for automatic driving by using the temperature difference between the interior and exterior of the vehicle. These devices can also obtain energy from exhaust pipes and other heating components, thereby improving fuel efficiency and reducing emissions.

The medical field can also benefit from this technology. Flexible thermoelectric equipment can use body heat to supply power for implantable medical equipment, so it does not need to replace the battery and reduces the risk of complications. In addition, the flexible thermoelectric equipment can also realize a continuous and non-invasive temperature monitoring system, providing valuable data for health monitoring.

On a larger scale, it is possible for flexible thermoelectric equipment to collect waste heat from infrastructure. By fitting the curved surfaces of pipes, machinery or building components, these devices can use previously undeveloped heat sources to generate electricity, thereby improving the energy efficiency of buildings and industrial processes.