Design optimization of a packaged thermoelectric generator for electrically active implants

Abstract

Thermoelectric generators (TEGs) are being considered as an alternative power supply for implantable medical devices. TEGs provide electrical power from temperature differences within the human body. However, the performance of implanted TEGs strongly depends on their geometry and implantation environment. Numerical simulations are performed to investigate the impact of various design variables on output power. This paper proposes a hermetically sealed housing, which supports optimum TEG performance when embedded in the human body. The model includes a TEG, a housing made from polyetheretherketone and metal plates for improved thermal tissue contact. The model also covers the surrounding tissue with its physiological thermal properties. The impact of housing and metal plate dimensions as well as the implantation depth is analysed via parameter studies. We consider patient and body region-specific tissue layer thicknesses through the evaluation of various layer thickness variations. Furthermore, we derive minimum dimensions of a packaged TEG, which is capable of providing 100μW power by automated design optimization.