Synergistic Effect of Carbon Nanotube Yarn Hybrid Energy Harvesters Based on Mechanical Stretching and Glucose

Energy harvesting, as a sustainable power source for implantable medical devices within the human body, is an intriguing area of research. The utilization of biochemical and biomechanical energy derived from the body offers a promising sustainable energy source. However, obtaining high power density in vivo is a challenge. Herein, energy harvesting is demonstrated using hybrid energy harvesters that simultaneously use mechanical energy from stretching and chemical energy from glucose. The hybrid energy harvesters operate as both biofuel cells (BFC) and mechano‐electrochemical energy harvesters (MEEH) within a single electrochemical cell. As a result, the hybrid energy harvesters offer a maximum power density of 17.8 W kg⁻¹ and an average power density of 15.1 W kg⁻¹. These values increase by 14.5% in maximum power density and 16.8% in average power density, compared to the sum of the power density obtained by mechanical stretching and glucose oxidation individually. Based on their improved performance and compact size, owing to the synergistic effect of the two electrochemical harvesting methods, these hybrid harvesters have the potential to be applied to implantable power sources.