A team of researchers at the Energy Conversion Materials Research Center of the Korea Electrotechnology Research Institute (KERI) has made a groundbreaking advancement in the field of thermoelectric generator technology. Their innovative approach involves the use of “mechanical metamaterials,” which are artificially designed materials that exhibit unique properties not found in nature. By harnessing the power of these metamaterials, the team has achieved the world’s highest level of flexibility and efficiency in thermoelectric generators.
Typically, when a material is stretched horizontally, it shrinks vertically. This phenomenon is known as Poisson’s ratio. However, mechanical metamaterials defy this conventional behavior and expand in both the horizontal and vertical directions when stretched horizontally. This negative Poisson’s ratio has allowed KERI to increase the stretchability of thermoelectric generators by up to 35%.
Thermoelectric generators are devices that convert temperature differences into electrical energy. They hold great promise as next-generation eco-friendly energy harvesting tools, as they can utilize wasted heat from various sources. However, previous designs using hard ceramic PCBs limited their applications to flat surfaces. Flexible materials like silicon and polymers were considered as alternatives but had thermal conductivity issues.
To overcome these limitations, the KERI team developed a flexible gasket with a metastructure. This deformable gasket provides structural stability to the thermoelectric generator, while also allowing it to be easily shaped, stretched, and attached to any surface. Moreover, its air-gap design enhances insulation, prevents heat loss, and increases the temperature difference within the generator by up to 30%, thus ensuring higher overall efficiency compared to existing flexible solutions.
The stretchability of KERI’s thermoelectric generators exceeds 35% and offers a power production density more than 20 times higher than previous designs. Even when greatly expanded, the generators show minimal deterioration in their electrical characteristics. These exceptional traits make them the most flexible and efficient thermoelectric generators in the world.
With potential applications in the fields of IoT, wearables, and medicine, KERI’s breakthrough holds significant promise. Wearable devices, for instance, typically rely on separate power supplies such as batteries. However, with KERI’s thermal energy harvesting technology, these devices can simply be attached to the body to generate electricity from body heat. The technology can also be applied to advanced medical devices.
Recognized for its excellence, the team’s research was recently published in the prestigious international journal Advanced Energy Materials. Dr. Hyekyoung Choi, the lead researcher, emphasized the importance of convergence research in achieving such groundbreaking results. By combining their expertise in high-performance thermoelectric materials, energy harvesting, and self-powered devices, the team has paved the way for the next generation of eco-friendly energy solutions.
Q: What is a thermoelectric generator?
A: A thermoelectric generator is a device that converts temperature differences into electrical energy.
Q: What are mechanical metamaterials?
A: Mechanical metamaterials are artificially designed materials that exhibit unique properties, such as expanding in both horizontal and vertical directions when stretched horizontally.
Q: What are the advantages of KERI’s flexible gasket?
A: KERI’s flexible gasket provides structural stability, stretchability, and insulation, significantly improving the efficiency of thermoelectric generators.
Q: What applications can benefit from this technology?
A: This technology holds promise in the fields of IoT, wearables, and medicine, enabling the production of flexible, self-powered devices that harness body heat for electricity generation.
Q: How do KERI’s thermoelectric generators compare to previous designs?
A: KERI’s generators offer over 35% stretchability and a power production density over 20 times higher than previous designs. They also exhibit minimal deterioration in electrical characteristics, even when greatly expanded.