A team of researchers at the Queensland University of Technology has developed an ultra-thin, flexible film that uses the body's heat to power wearable devices, eliminating the need to rely on traditional batteries. This breakthrough technology not only brings sustainable energy solutions to wearable devices, but also effectively cools electronic chips, helping smartphones and computers run more efficiently.
The research team led by Professor Chen Zhigang published the results in the prestigious journal Science. He said the technology solves a major challenge in making flexible thermoelectric devices that convert body heat into electricity, opening up new energy options for future wearables.
What is body thermal power supply technology?
Bulk thermal power supply technology, as the name suggests, is the use of heat generated by the human body to power electronic devices. The human body temperature is usually around 37°C, and this heat can be converted into electricity by specific thermoelectric materials and supplied to the device. To put it simply, body thermal power technology uses the heat of our body to keep the device working like an inexhaustible source of energy.
The prospect of bulk thermal power supply technology
Professor Chan pointed out that flexible thermoelectric devices can be comfortably worn on the skin and converted into electricity by using the temperature difference between the human body and the surrounding environment. This technology not only provides continuous power to wearable devices, but also helps cool the electronic chips inside smart devices to improve performance.
In addition, Professor Chan believes that the potential of this technology goes far beyond that. Body thermal power can also be used in personal thermal management, powering wearable heating, ventilation, and air conditioning systems to make devices smarter.
Figure: Ultra-thin flexible film allows body heat to power devices and say goodbye to battery shackles (Source: Techxplore).
Challenges and breakthroughs
While the technology looks promising, there are some challenges to flexible thermoelectric devices before they can be commercialized. Traditional thermoelectric equipment suffers from poor flexibility, complex manufacturing, high cost, and insufficient performance. Bismuth telluride based materials, in particular, have many limitations, although they perform well in low-power applications.
To address these issues, a team of researchers at the Queensland University of Technology has developed a cost-effective technique to fabricate flexible thermoelectric films from tiny crystals or "nanobinders". This not only increases efficiency and flexibility, but also makes the manufacturing process easier.
"We have created a printable A4 size film with record-high thermoelectric performance, excellent flexibility, scalability and low cost, making it one of the best flexible thermoelectric materials available," said Professor Chen.”
Technical implementation
This technology uses the method of "solvothermal synthesis", in which nanocrystals are formed by a solvent at high temperatures and pressures, and combines screen printing and sintering techniques. Screen printing enables large-scale production of films, while sintering heats the film close to its melting point, bringing the particles together.
The team's technology can also be used with other systems, such as silver-selenide-based thermoelectric materials, which may be cheaper and more sustainable than traditional materials.
Future outlook
As this technology advances, Professor Chan believes that flexible thermoelectric technology will play an increasingly important role in future wearables and other electronic products. This not only provides a steady stream of power to the devices, but also provides an efficient cooling solution for the electronics, driving the more efficient operation of the smart devices.
Overall, bulk thermal power technology has brought unprecedented energy freedom to future wearable devices, and breakthroughs in flexible thermoelectric materials have opened up a wide range of prospects for the application of this technology.
