Preparation and Evaluation of PVDF-HFP-Based Gel Electrolyte for Ge-Sensitized Thermal Cell

• Published in: Polymers Vol. 16; no. 12; p. 1732
• Main Authors: Chai, Yadong, Matsushita, Sachiko
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 18-06-2024; MDPI
• Subjects: Alternative energy sources; Chemical synthesis; Climate change; Diffusion coefficient; Diffusion rate; Electricity distribution; Electricity generation; Electrodes; Electrolytes; Ethanol; Fluorides; gel polymer electrolyte; Geothermal power; Greenhouse gases; Ion diffusion; Molecular structure; Open circuit voltage; Polyethylene glycol; Polymers; redox reaction; renewable energy; semiconductor; Short circuit currents; Temperature; Thermal energy; thermal energy conversion; thermoelectric material; Tin; United States > US; Japan; renewable energy; semiconductor; thermal energy conversion; gel polymer electrolyte; redox reaction; thermoelectric material
• ISSN: 2073-4360; 2073-4360
• DOI: 10.3390/polym16121732

The semiconductor-sensitized thermal cell (STC) is a new thermoelectric conversion technology. The development of nonliquid electrolytes is the top priority for the practical application of the STC. In this study, a novel gel polymer electrolyte (PH-based GPE) composed of poly(vinylidenefluoride-
-hexafluoropropylene) (PH), 1-Methyl-2-pyrrolidone (NMP), and Cu ions was synthesized and applied to the STC system. The PH-based GPE synthesized at 45 °C showed higher open-circuit voltage (-0.3 V), short-circuit current density (59 μA cm
) and diffusion coefficient (7.82 × 10
m
s
), indicating that a well-balanced structure among the NMP molecules was formed to generate a high-efficiency conduction path of the Cu ions. Moreover, the ion diffusion lengths decreased with decreasing content rates of NMP for the PH-based GPEs, indicating that the NMP plays an important role in the diffusion of Cu ions. Furthermore, the activation energy was calculated to be 107 kJ mol
, and that was smaller compared to 150 kJ mol
for the poly(ethylene glycol)-based liquid electrolyte. These results play an important reference role in the development of electrolytes for STC systems. At the same time, they also provide a new avenue and reference indicator for the synthesis of high-performance and safe GPEs.