1. Background of proton exchange membrane fuel cells
Proton exchange membrane fuel cell (PEMFC): It is a power generation device that uses a proton-conducting polymer membrane as an electrolyte to directly convert the chemical energy present in the fuel into electrical energy through an electrochemical reaction. The fuel cell has With high power generation efficiency, low environmental pollution, low noise and high reliability, relevant departments and experts in my country attach great importance to fuel cells and emphasize the importance and necessity of independent research and development of fuel cell systems.
The structural composition of PEMFC is shown in the figure, which is mainly composed of core components such as proton exchange membrane (electrolyte), catalyst layer, gas diffusion layer and bipolar plate. The gas diffusion layer, catalyst layer and polymer electrolyte membrane are prepared through a hot pressing process to obtain a membrane electrode assembly (MEA).
he proton exchange membrane in the middle plays the multiple roles of conducting protons (H+), preventing electron transfer, and isolating cathode and anode reactions; The catalyst layers on both sides are the place where fuel and oxidant undergo electrochemical reactions; The main functions of the gas diffusion layer are to support the catalyst layer, stabilize the electrode structure, provide gas transmission channels and improve water management; The main function of the bipolar plate is to separate the reaction gases and introduce the reaction gases into the fuel cell through the flow field, collect and conduct current, support the membrane electrode, and undertake the heat dissipation and drainage functions of the entire fuel cell.
In the context of global energy low-carbon transformation, hydrogen energy, as a clean secondary energy, will become one of the main energy sources in the future society. Fuel cells can efficiently convert the chemical energy of hydrogen energy into electrical energy. The rapid development of fuel cell technology Development is the core goal of the industry. Current applications of fuel cells include automobiles, ships, aviation, power stations, etc. The requirements for high stability and high durability have been put forward for the performance of fuel cells and bipolar plates respectively. As the core component of fuel cells, coated metal bipolar plates have become one of the key technologies that the industry needs to overcome.
2. Coating performance
Coatings currently available for commercial application include precious metal coatings and carbon coatings. Sydrogen star hydrogen source uses a unique The carbon coating prepared by FCVA (Technical Filtered Cathode Vacuum Arc Technology) has excellent properties beyond precious metals and can be applied to a variety of fuel cell scenarios.
1. SydroDIAMOND® (Metal bipolar plate coating for PEM fuel cells, a noble metal-free bipolar plate coating that enhances the conductivity of the material and protects the substrate from passivation.) Carbon coating passes The electrochemical workstation was tested offline under simulated PEMFC operating conditions to evaluate its durability; a contact resistance tester was used to test under a pressure of 1.0MPa to evaluate its conductivity.
1) As a good conductor, gold has good electrical conductivity, and SydroDIAMOND® carbon coating has comparable electrical conductivity to precious metal coatings;
2) Polarization test results show that SydroDIAMOND® carbon coating has a higher corrosion potential and an overall lower corrosion current;
3) When tested at a constant high potential of 1.80V, SydroDIAMOND® carbon coating has better corrosion resistance;
4) When tested at a constant low potential of 0.84V, SydroDIAMOND® carbon coating has comparable durability to precious metals;
5) Perform a CP test on the solution after the electrochemical test to analyze the ion precipitation amount. The ion precipitation amount of the precious metal coating is 286pg/L, and the ion precipitation of the SydroDIAMOND® carbon coating is less than 30ug/L, which has excellent anti-ion precipitation ability.
2. Send the SydroDIAMOND® carbon-coated plates to ZBT and assemble them into the fuel cell for benchmarking testing. After testing for nearly 500H at a voltage of 0.6V, the results show that the uncoated plate has the lowest battery output performance.
SydroDIAMOND® carbon coating has better output performance than precious metal coating. At the same time, looking at the attenuation, SydroDIAMOND® carbon coating shows Better stability.
3. FCVA technical advantages
Star Hydrogen Source's proprietary FCVA technology is capable of depositing 100% pure high-energy ions on a variety of material substrates. This coating technology significantly enhances material properties (e.g. electrochemical performance, corrosion resistance) while filtering out undesirable large particles that impact coating quality and integrity. Coatings can be precisely adjusted and optimized according to the application.
The coating process takes place at temperatures close to room temperature, ensuring greater energy efficiency. In addition to traditional materials such as metals, vacuum coating technology can be applied to a wider variety of traditionally challenging substrates such as plastics, rubber and ceramics.
Star Hydrogen Source's FCVA technology has been applied to large-scale production in multiple industries such as 3C (computer, communications and consumer electronics), automobiles, precision engineering and printing.
By using foundational materials technologies, Sydrogen delivers advantages across the hydrogen value chain in the performance, durability and cost of key fuel cell components.
SydroDIAMOND® carbon-coated bipolar plates have excellent electrical conductivity, high potential corrosion resistance, low potential durability, resistance to chloride ion corrosion, low iron ion precipitation and other advantages, and are suitable for diverse fuel cell application scenarios. SydroDIAMOND® carbon-coated bipolar plates have passed tests on many clients, including offline tests, bench stack tests, system function tests, actual operations of buses, heavy trucks, fixed power stations, etc. Customer feedback has been good.
In addition, due to the use of low-cost carbon material processing and continuous line production, SydroDIAMOND® carbon-coated bipolar plates have obvious cost advantages. After technological iteration, while ensuring performance, the latest generation of coatings has better performance and lower mass production costs, promoting further cost reduction and efficiency improvement.
4. Company introduction
Star Hydrogen (Shanghai) Technology Co., Ltd. (hereinafter referred to as "Star Hydrogen") is a joint venture established by NANOFILM TECHNOLOGIES INTERNATIONALLIMITED, Asia's leading deep technology advanced material solutions provider, and Temasek EMASEK HOLDINGS. Star Hydrogen Star Hydrogen Source develops and manufactures components, products and systems for fuel cells and electrolyzers, bringing innovative technologies to the market to achieve green energy transformation. Star Hydrogen Source is headquartered in Singapore and has rich experience in hydrogen energy technology. Star Hydrogen Source also cooperates with Singapore's leading Cooperating with universities to commercialize the latest technology through our products, Star Hydrogen Source's coating equipment and coating technology R&D are located in our Shanghai factory, with an independent development testing and technology verification center for hydrogen energy materials and key parts, with a total factory area of 5000 square meters and currently has more than 100 employees.