Harvesting energy is a win in just about any application. In wearable health tech, however, energy harvesting should sit at the top of a developer’s wish lists. If users need to refuel, plug in, or recharge the technology that they wear, carry, or implant, they are less likely to stick with the device unless it is necessary for survival. “If wearable Health Tech devices are to be successful, they are going to have to disappear into our lives,” Health Tech Insider’s Alfred Poor predicted in mid-2015 when he wrote about Tekcapital’s role in licensing energy harvesting technologies.

Engineers at Purdue University have developed technology that conserves and converts mechanical energy to power. Led by Professor Wenzhou Wu, the Purdue team extended a concept used in science fiction films in which robots use liquid metal as a shape-shifting component. Wu’s group invented an energy harvesting transducer that consists of liquid metal embedded in functional silicon held between two layers of Ecoflex, an extremely strong, soft and stretchy rubber. As the device bends, it can convert the motion or pressure into electrical energy. The Purdue team published a paper about their nanogenerator, called the LMI-TENG, in the Journal of Materials Chemistry A.

According to Wu, applications for self-powered technologies such as LMI-TENG include wearable sensors, advanced health care, human-machine interfaces, robotics, augmented, virtual, and mixed reality, and others. As work continues at Purdue and elsewhere, ongoing development in a wide range of health wearables will support a variety of energy-harvesting technologies that operate in different environments and at various scales.