The data show that the life of the metal plate stack is not necessarily shorter than that of the graphite plate stack, and the metal plate stack has obvious advantages in terms of power, power density, weight, volume, vibration resistance, batch preparation, cold start and so on. At present, the domestic metal plate stack is developing rapidly, and some performance indicators have reached the world's advanced level, ushering in a new cycle of industrial development.
At the 2021 Annual Meeting of Gaogong Hydrogen, Dr. Qi Zhigang, Chief Technology Officer of Xinyan Hydrogen Energy, delivered a keynote speech on "Metal Plate Fuel Cells Usher in a New Cycle of Industrial Development". Qi Zhigang said: "I have been engaged in the fuel cell industry for more than 20 years, the entire industry technology and process level is getting higher and higher, in recent years, the domestic technology, process, batch preparation, demonstration operation and other aspects have also made significant progress, but so far there is no fundamental change in the fuel cell material system, I expect that the revolutionary breakthrough of core materials will not appear in the short term." ”
From the perspective of the plate, the plate is the core component of the stack, which plays an important role in isolating the fluid, conducting heat and electricity, supporting the membrane electrode and maintaining the configuration of the stack, which is a key factor affecting the performance and life of the stack. The design of the stack is very demanding on the plate, and there can be no molecular-sized needle eye, otherwise the three fluids will be cross-stringed; in addition, the plate must have good strength.
The operating environment of fuel cells is very harsh: high voltage, high oxidation, high humidity, so corrosion resistance is a difficult problem. For many years, the material used to make plates was still graphite or metal. Comparing the metal plate with the graphite plate, except for the poor corrosion resistance when there is no plating, the other characteristics exceed the graphite material.
The corrosion resistance of the metal plate can be solved by surface treatment, while the gas resistance, brittleness and vibration resistance of the graphite plate are not easy to solve. A good coating will make the life of the metal plate stack no shorter than the graphite plate stack. In fact, in recent years, judging from news reports, some companies have made significant progress in the life of metal plates, achieving a "big leap" from 5,000 hours to 10,000 hours or even 30,000 hours.
For example, in October 2021, United Fuel Cell System R&D (Beijing) Co., Ltd. and Huafeng Fuel Cell Co., Ltd. will start selling the first fuel cell system "TLPower100" developed and produced for commercial vehicles in China. Through the localization of the system product in China, the industry's top 711W/kg, 4.9kW/L high power density (rated power 101kW) and 30,000 hours of ultra-long durability. Its metal stack module is from Toyota, and the durability of 30,000 hours is almost comparable to the performance of the current excellent graphite stack.
On the basis of durability, the metal plate stack can achieve higher power and power density, can also achieve lower low temperature start, even at minus 40 degrees can also achieve helpless cold start, easy to mass production, meet the requirements of the vehicle standard, more competitive.
Since the advantages of metal plates are significant, why is its development lagging behind graphite plates at this stage? Qi Zhigang believes that it is because the design and manufacturing of metal plates is very difficult, compared with graphite plates is not an order of magnitude: 1, the cathode plate and the anode plate are highly correlated, can not be independently designed; 2, the coolant flow field is composed of the back of the cathode flow field and the back of the anode flow field, can not be designed separately; 3, the plate in several processes have the possibility of deformation: stamping, cleaning, welding, plating; 4, need to consider the characteristics of the plate and the difficulty of processing, can not have the size of the needle eye; 5, the larger the area of the plate, The more difficult the processing.
However, from the perspective of market application, significant progress has still been made in the field of sheet metal stacks in 2021. According to data from the Institute of Hydrogen and Electricity (GGII), the proportion of metal plate stack shipments has further increased this year. Among the 2021 H1 shipped stacks, graphite (including composite) plate stacks account for 55%, and metal plate stacks account for 45%. It is expected that the metal plate stack is expected to split the market with the graphite (including composite) plate stack throughout this year.
From the perspective of enterprise progress, the number of enterprises involved in metal plates and stacks and systems has increased significantly, and some graphite plate-related advantageous units have turned to metal plates.
Xinyan Hydrogen Energy is one of the few domestic metal plate stack companies that has independently mastered the technology and process of metal plate design, molding, cleaning, welding, anti-corrosion plating, etc., as well as the R&D and manufacturing capabilities of metal plate stacks, modules, systems, test benches and voltage inspection boards at home and abroad. The company's technology and process chain on the metal stack are relatively perfect, from the design of the metal plate at the beginning to the integration of the fuel cell system at the end can be completed independently, which is conducive to cost and production process control.
Xinyan Hydrogen Energy has three subsidiaries of Beijing Xinyan, Dalian Qingyan and Datong Xinyan, focusing on metal plate design and stack research and development, fuel cell system control integration and test bench, industrial base operation, and the self-developed metal plate stack automated production line in Datong has been put into operation in April 2020. Profound technology precipitation, perfect process chain, excellent testing capabilities and large-scale production capacity construction have built a strong comprehensive competitive advantage of xinyan hydrogen energy.
The new hydrogen energy has also been favored by the capital side. This year, the new investors led by Beijing Yizhuang International Investment and Development Co., Ltd. injected capital into the company, which played a strong role in promoting the company's better and faster development.
Since 2021, the new hydrogen energy has also achieved remarkable results in the development of technology: completed the development of 85kW and 115kW metal plate stacks and their corresponding 70kW and 90kW fuel cell systems, and developed 180kW class fuel cell modules and their corresponding 140kW fuel cell systems using 90kW double stack structures; single battery homogeneity is good, the stack power density is 4.4kW/L, the insulation resistance of fuel cell modules is greatly improved, and the integration of fuel cell systems is improved. The control logic is more perfect.
New hydrogen energy 2022 plate stack and system planning: the development of rated power 160kW class stacks; the completion of the design and verification of metal plates for rated power 200kW stacks; the finalization and provision of 50kW, 70kW, 90kW, 110kW, 130kW ~ 150kW fuel cell system series products; the development of high-power electrolytic cell test bench. "We will shift the focus from power density to engineering, integration, reliability, cost reduction, etc." Qi Zhigang said.