Fabrication of Bipolar Plates from Thermoplastic Elastomer Composites for Vanadium Redox Flow Battery

Abstract

A vanadium redox flow battery (VRFB) is a promising large-scale energy storage device, due to its safety, durability, and scalability. The utilization of bipolar plates (BPs), made of thermoplastic vulcanizates (TPVs), synthetic graphite, woven-carbon-fiber fabric (WCFF), and a very thin pyrolytic graphite sheet (GS), is investigated in this study. To boost volumetric electrical conductivity, WCFF was introduced into the TPV composite, and the plate was covered with GS to increase surface electrical conductivity. Created composite BPs acquire the desired electrical conductivity, mechanical strength, and deformation characteristics. Those properties were assessed by a series of characterization experiments, and the morphology was examined using an optical microscope, a scanning electron microscope, and atomic force microscopy. Electrochemical testing was used to confirm the possibility of using the suggested BP in a working VRFB. The laminated BP was utilized in a flow cell to electrolytically convert V(IV) to V(V) and V(II), which achieved comparable results to a commercial graphite bipolar plate. Following these experiments, the laminated bipolar plates’ surfaces were examined using X-ray photoelectron spectroscopy, and no evidence of corrosion was found, indicating good durability in the hostile acidic environment.

Performance Evaluation for Ultra-Lightweight Epoxy-Based Bipolar Plate Production with Cycle Time Reduction of Reactive Molding Process

“…Figure 8 illustrates hysteresis loops gained from 1000 loading and unloading with compressive force. The area of the hysteresis loop represents the strain displacement indicating plastic deformation as a function of time [ 67 , 68 ]. In terms of higher force applied in long-term durability, it may lead to cracking phenomena in a bipolar plate structure that negatively affects the machining process during the BP fabrication and gas leakage or voltage decay during the PEMFC operation.…”

“…Furthermore, these bonds enhanced the performance of filler dispersion in the epoxy matrix. It is worth noting that the conductivity of the epoxy composites depends upon composite density and thickness based on various weight ratios of the epoxy composite to the WCFS layers [ 68 , 76 ]. The ratio also affects the viscosity of the epoxy/nanofiller suspension that is needed to achieve the desired dispersion of nanofillers on WCFS surfaces and the interface of composite laminates [ 28 ].…”

Self-Discharging and Corrosion Problems in Vanadium Redox Flow Battery

“…12. Stronger plastic binder such as proposed by several researchers (Satola, 2021;Kim et al, 2014;Onyu et al, 2022) is needed to resist highly acid liquid, such as Vanadium electrolyte.…”

Effect of alfa fiber loading on the mechanical, physical and dielectric properties of epoxy-amine composite

“…Its values vary from 0.94 to 1.03 mm. The invented epoxy composites were placed between the carbon paper electrode, and they inserted between the gold coated copper plate 15 and it was analyzed using a contacting electrode method, which uses a rigid metal electrode at room temperature and at different frequency values from 0.1 MHz to 1 MHz.…”