Production of Ni<SUB>65</SUB>Cr<SUB>15</SUB>P<SUB>16</SUB>B<SUB>4</SUB> Metallic Glass-Coated Bipolar Plate for Fuel Cell by High Velocity Oxy-Fuel (HVOF) Spray Coating Method

Abstract

In this study, the newly designed bipolar plate for proton exchange membrane fuel cells (PEMFC) was produced by spray-coating the Ni 65 Cr 15 P 16 B 4 metallic glassy alloy on Al plate. The Ni 65 Cr 15 P 16 B 4 metallic glass was adopted as a coating material because of its excellent corrosion resistance and the high velocity oxy-fuel (HVOF) spray coating was used for the metallic glass deposition on the Al plates having a bipolar plate flow field.The corrosion resistance of the Ni 65 Cr 15 P 16 B 4 glassy alloy film produced by the HVOF spray-coating was studied under simulated PEMFC environments. As a result, the Ni 65 Cr 15 P 16 B 4 glassy alloy film showed lower corrosion current density than the high-corrosion-resistant stainless steel SUS316L. Then, the electricity generation tests with the single cell having the Ni 65 Cr 15 P 16 B 4 glassy alloy-coated bipolar plates produced in this study were conducted. As a result, the single cell with the metallic glass-coated bipolar plates showed very high I-V performance as well as the cell with the carbon bipolar plates. The long time durability tests for 24 h were also conducted at the constant current density of 200 mAÁcm À2 . As a result, the single cell with the glass-coated bipolar plates showed no voltage drop during the test. So, it was found in this study that the Ni 65 Cr 15 P 16 B 4 glassy alloy-coated bipolar plate produced by the HVOF spray-coating have a potential for practical use for the fuel cells.

Production of Ni-P Amorphous Alloy-Coated Bipolar Plate for PEM Fuel Cell by Electro-Less Plating

“…The single cell with the carbon bipolar plates did not show a significant voltage drop during the measurement. 10) On the contrary, the single cell with the Al bipolar plates showed the largest voltage drop during the measurement.…”

“…Figure 7 shows the I-V curves of the single fuel cell with the Ni-P amorphous alloy-coated bipolar plates (hereafter denoted as Ni-P bipolar plates) measured at 353 K. The gas flow rate of H 2 and O 2 was 0.1 LÁmin À1 . The I-V curves measured with the carbon graphite and Al bipolar plates were reported in our previous paper 10) and were also superimposed on the figure for comparative purpose. We used a new MEA for each I-V measurement in this work.…”

Corrosion Resistant Al‐Cr‐Mo Alloy Coating on Type 316L Stainless Steel Bipolar Plates for Proton Exchange Membrane Fuel Cell Applications

“…Ag coated type 316L SS exhibited a high corrosion resistance in simulated fuel cell environment and displayed a wide potential plateau from 0 V SCE to approximately 0.8 V SCE where the current density was almost independent of the potential [21]. High velocity oxygen fuel (HVOF) spraying is a thermal spray technique utilizing the combustion of gases such as hydrogen or a liquid fuel, such as kerosene, creating high velocity particles to bombard on the substrate material [25]. Different types of metals, their nitrides and multilayers (e.g., Ta, MoN, CrN, TiN, Ti/TiN, Ti/CrN, Cr/CrN/Cr) produced through plasma nitriding, electroplating, electroless deposition, high velocity oxy-fuel (HVOF), sol-gel, pack cementation, electrochemical insertion, thermo reactive deposition, chemical vapour deposition (CVD) and physical vapour deposition (PVD) have been widely researched as protective alloy coatings for BPPs.…”

Production of Ni-Based Glassy Alloy-Coated Bipolar Plate with Hydrophilic Surface for PEMFC and Its Evaluation by Electrochemical Impedance Spectroscopy

“…The bipolar plate is 95 mm long, 95 mm wide and 19 mm thick, different from that in our previous report. 4) A glassy alloy-coated bipolar plate was produced by spray-coating the glassy alloy on the surface of the SUS316L bipolar plate. A high velocity oxy-fuel (HVOF) thermal spray system (PRAXAIR/TAFA, JP-5000) was used to produce Ni 65 Cr 15 P 16 B 4 thick coating film on a high corrosion-resistant SUS316L stainless steel bipolar plate with a flow field.…”

“…1,2) We have previously focused on their good corrosion resistance and have studied the possibility of employing a glassy alloy as a bipolar plate material for a proton exchange membrane fuel cell (PEMFC). 3,4) Fuel cells are recognized as strong candidates for a new clean power source. 5) Further development is needed before fuel cells can be employed in our daily life, and numerous efforts have been devoted to overcome the technical difficulties of fuel cell technology.…”