Pyroelectric conversion—Effects of P(VDF–TrFE) preconditioning on power conversion

Large amounts of low-grade heat are emitted from various industries and wasted into the environment. This heat energy can be used as a free source for pyroelectric power generation. We first discuss the principle of pyroelectric conversion based on the differences in crystal structures of copolymer. Then we discuss the pyroelectric conversion of waste heat using copolymer films containing 60% vinylidene fluoride (VDF) and 40% trifluoroethylene (TrFE) and the impact of the preconditioning of the pyroelectric films on the net power output. We discovered that the pre-polarization (poling) of pyroelectric films has a significant beneficial effect by decreasing internal conduction during power conversion. This in turn increased net power output. We were able to reach 95–165 J/L of copolymer used in each cycle even including the internal leakage. We also showed it is critically important to operate the power conversion near the phase transition where electron discharge is the highest.