Research Report on Solid-state Hydrogen Storage: Prominent Technical Advantages with Broad Application Prospects
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Zhonglin International Group Date：04-10 869 Belong to：Industry Related
China's hydrogen energy industry enjoys substantial potential
According to the prediction of the China Hydrogen Alliance, under the vision of peaking carbon emissions by 2030, the annual demand for hydrogen in China is expected to reach 37.15 million tons, accounting for approximately 5% of terminal energy consumption; The renewable hydrogen production is about 5 million tons, and the installed capacity of the deployed electrolysis tank is about 80GW. Under the vision of carbon neutrality by 2060, the annual demand for hydrogen in China will increase to about 130 million tons, accounting for about 20% of terminal energy consumption. Among them, the proportion of hydrogen used in the industrial sector is still the largest, about 77.94 million tons, accounting for 60% of the total hydrogen demand; 40.51 million tons of hydrogen are used in the transportation sector, 5.85 million tons are used in the construction sector, and 6 million tons are used for power generation and grid balance.
Hydrogen storage - three approaches: gas, liquid, and solid states
Gas hydrogen storage technology compresses hydrogen gas into high-pressure containers to achieve hydrogen storage, usually made of steel, aluminum, carbon/glass fiber, polymer materials, etc.
High-pressure gaseous hydrogen storage technology is mature and widely used. At present, high-pressure gaseous hydrogen storage technology is mainly applied in the transportation field, and high-pressure hydrogen storage cylinders are used as hydrogen storage devices in hydrogen refueling stations and fuel cell vehicles. Hydrogen refueling stations usually use Type I and Type II cylinders made of pure steel (steel inner liner, fiber circumferential winding), with a working pressure of 17.5-30MPa and a large volume. The cost of installing a 250kg hydrogen storage device in a hydrogen refueling station is about 1.7 to 2 million yuan, which is equivalent to a unit hydrogen storage price of about 6000-8000 yuan/kg. Car mounted hydrogen storage bottles are mainly divided into two types: Type III bottles and Type IV bottles. The pressure of Type III bottle is 35MPa, the inner liner is made of aluminum alloy/steel, and the wrapping material is carbon fiber or mixed carbon/glass fiber composite material. The pressure of Type IV bottle is 70MPa, and the inner liner is made of polymers (generally including nylon, high-density polyethylene (HDPE), PET polyester plastic/PA polyamide). The external wrapping material is mainly carbon fiber or mixed carbon/glass fiber composite material. The hydrogen storage tanks equipped on domestic hydrogen fuel cell vehicles are mainly 35MPa Type III cylinders, while the 70MPa Type IV high-pressure hydrogen storage tank has been applied abroad but has not yet been approved domestically. The high-pressure hydrogen storage cylinder used in fuel cell vehicles is converted based on the hydrogen storage mass, with a unit price of 3500-5000 yuan/kg for 35MPa and 8000-10000 yuan/kg for 70MPa.
Liquid hydrogen storage technology uses low-temperature technology to cool hydrogen gas to below the liquefaction temperature (-253 ℃ under standard atmospheric pressure), and store it in liquid form in highly vacuum insulated containers.
Low temperature liquid hydrogen storage technology has achieved large-scale commercial applications in the United States, Japan, and other countries, and its domestic application started in military, aerospace, and other fields. With the rise of the domestic hydrogen energy industry in recent years, the civilian liquid hydrogen field has gathered a group of scientific research institutions and enterprises such as Zhongke Fuhai, Aerospace 101 Institute, Guofu Hydrogen Energy, and Hongda Xingye, and has repeatedly made significant breakthroughs in related technologies; At the same time, the country has released national standards for the production, storage, and transportation of liquid hydrogen, which provides a basis for civilian use of liquid hydrogen and achieves zero breakthroughs in the civilian field standards of China's liquid hydrogen industry, providing important support for the market-oriented development of liquid hydrogen. The price of liquid hydrogen tank trucks is 3.5 million yuan per unit, which can store 4300 kilograms of liquid hydrogen. The liquefaction process consumes approximately 15KWh/kg of electricity. In January 2021, Tsinghua and Beiqi Foton jointly launched the world's first 35 ton and 49-ton distributed drive liquid hydrogen fuel cell heavy-duty commercial vehicle, which successfully passed comprehensive testing. In February 2021, Shanghai Reshape, Fosun Energy, Guofu Hydrogen Energy, and Taiji Power signed an agreement to cooperate in promoting the liquid hydrogen storage and refueling station project in Foshan.
Solid-state hydrogen storage technology combines hydrogen with hydrogen storage materials through physical or chemical means to achieve hydrogen storage. There are metal alloys, carbon materials, etc. in terms of material classification. Metal hydride alloys can be further divided into rare earth series, titanium iron/manganese series, vanadium series, and magnesium series.
Solid-state hydrogen storage is one of the most commercially viable storage methods considering factors such as volumetric hydrogen storage density and safety. Solid state hydrogen storage has started relatively early in the transportation field, with demonstration projects for hydrogen bicycles, two wheeled vehicles, fuel cell forklifts, and hydrogen refueling stations; Domestic enterprises such as Houpu Group are also developing solid-state hydrogen storage bottles for vehicles. Currently, the price of titanium based hydrogen storage devices is 20000 yuan/kg. In the future, they hope to reduce it to below 8000 yuan/kg through large-scale production. Solid state hydrogen storage also has demonstration projects in the field of power peak shaving, including Huadian Group, Yunnan Electric Power Research Institute, Youyan Technology Group, etc., which have built related demonstration projects in Luding, Kunming, and Zhangjiakou, Sichuan. In the field of backup power supply, demonstration projects applied in industrial and commercial areas such as data centers, hospitals, and communities. In the industrial field: Currently, high-pressure gas storage tanks are used in chemical engineering, which pose safety challenges and high complexity. Solid hydrogen storage can be used for long-term storage, reducing safety pressure; It can also achieve the integration of industrial by-product hydrogen purification, storage and transportation. A storage and transportation vehicle can directly fill and purify 1.2 tons of hydrogen, obtaining 99.999% high-purity hydrogen, effectively reducing storage and transportation costs.
Introduction to Solid-state Hydrogen Storage Technology
The solid-state hydrogen storage technology can be mainly divided into metal hydrides, coordination hydrides, carbon materials, metal organic framework materials (MOFs), and hydrate hydrogen storage. Metal hydrides are the mainstream technology route for solid-state hydrogen storage, involving materials such as magnesium, titanium, vanadium, rare earth, and composite hydrogen storage alloys; Magnesium based alloys have a large hydrogen storage capacity (up to 7.6%), but their hydrogen release temperature is high, usually requiring 300 ℃; The hydrogen storage capacity of titanium based, vanadium based, and rare earth based hydrogen storage alloys varies from 1.4% to 2.4%, and the hydrogen release temperature is significantly lower than that of magnesium based alloys. The coordination hydride route requires alkali metals (lithium, sodium, potassium, etc.) or alkali earth metals (magnesium, calcium, etc.) or third main group elements (aluminum, boron, etc.). The carbon material route requires materials such as activated carbon, carbon nanofibers, and carbon nanotubes.
Basic principles of metal hydride absorption and desorption
Metal hydrogen storage materials store hydrogen in alloys in the form of metal hydrides. During the hydrogen absorption process, alloy hydrogen storage materials undergo exothermic reactions at a certain temperature and hydrogen pressure to absorb hydrogen and generate metal hydrides; During the hydrogen release process, metal hydrides undergo endothermic reactions under heating to release the absorbed hydrogen gas,. Microscopic mechanism: Hydrogen molecules first adsorb on the metal surface and dissociate into hydrogen atoms as hydrogen bonds break. Hydrogen atoms diffuse into the gaps between metal atoms through internal diffusion, forming a metal solid solution. Then, hydrogen atoms in the solid solution further diffuse into the metal interior, achieving the activation energy of solid solution conversion into chemical adsorption, and forming hydrides.
Hydrogen Storage and Transportation: Three Forms of Combined Application Prospects
For high-pressure gaseous storage and transportation, the transportation cost is 3.6 yuan/kg when the transportation distance is 50km. As the distance increases, the transportation cost of long tube trailers increases significantly. When the transportation distance is 500km, the transportation cost of hydrogen reaches 29.4 yuan/kg. Therefore, long tube trailers are only suitable for short distance transportation (less than 200km). The transportation cost of solid hydrogen storage vehicles and liquid hydrogen tank trucks is not sensitive to distance. When the hydrogen refueling station is 50-600km away from the hydrogen source point, the transportation price is about 10-13 yuan/kg. The cost change is related to the electricity consumption and hydrogen load during the hydrogen storage and transportation process. In long-distance transportation, both solid hydrogen storage vehicles and liquid hydrogen tank trucks have cost advantages. The cost of transporting hydrogen through pipelines mainly comes from the depreciation and maintenance costs of pipes that are positively correlated with the transportation distance. When the transportation distance is 100km, the cost of transporting hydrogen is only 0.5 yuan/kg. However, the cost of pipeline hydrogen transportation is largely influenced by the demand side. In the current situation where hydrogen refueling stations are not yet widespread and stations are relatively scattered, the cost advantage of pipeline hydrogen transportation is not obvious.
Solid-state hydrogen storage technology has broad application prospects
There are different suitable scenarios for different hydrogen storage methods. The scenarios suitable for solid-state hydrogen storage include:
Engineering vehicle applications: 1) Forklifts are not sensitive to weight, and solid-state hydrogen storage is more suitable. Compared to high-pressure gas storage tanks, solid-state hydrogen storage can store more than twice the amount of hydrogen, doubling the endurance time. Forklifts can work continuously for a whole day with one hydrogenation operation. 2) Solid hydrogen storage can be used as a logistics vehicle for short distance transportation in port areas and coal mines. In this scenario, using high-pressure gas tanks poses safety risks, and using solid hydrogen storage is more suitable. 3) Mechanical construction vehicles in subway construction are also suitable for using solid-state hydrogen storage devices. These trains have very few station constructions, but they have stronger load-bearing capacity for volume and weight. 4) Fixed route heavy-duty trucks, sanitation vehicles, and so on are also very suitable.
Passenger car applications: Currently, fuel cell passenger cars mainly use high-pressure hydrogen storage. The mainstream models use three tanks, one horizontally and two vertically, which takes up more space. If a solid-state hydrogen storage device is used, it can be integrated with the chassis design, similar to electric vehicles, which will greatly improve space utilization. At the same time, the center of gravity of the car will be reduced, the resistance of the car will be reduced, and energy efficiency will be improved; At the same time, solid-state hydrogen storage has better safety, allowing vehicles to safely enter underground garages for parking. The current problem is that it is necessary to improve the quality hydrogen storage density to over 2% and reduce manufacturing costs when using passenger cars.
Backup power supply for communication base stations: For example, after the Wenchuan earthquake in 2008 in China, some units developed a backup power supply consisting of fuel cells and solid-state hydrogen storage devices, which can supply communication base stations with a power supply for about 17 hours at a time.
Distributed energy supply: Solid state hydrogen storage devices can be used in conjunction with photovoltaic or wind power. Due to the low hydrogen pressure required for solid-state hydrogen storage, hydrogen produced by photovoltaic electrolysis of water can be directly stored in solid-state hydrogen storage devices. Solid state hydrogen storage devices are usually stored at room temperature and pressure, and are used in conjunction with fuel cells. The waste heat from fuel cells can be used for hydrogen release, and the solid-state hydrogen storage device can be used as part of the heat exchange system. In recent years, larger scale distributed energy storage, such as the distributed energy supply in Nansha, Guangzhou and Kunming, Yunnan, can be directly combined with fuel cell cogeneration. On the other hand, hydrogen gas can be pressurized and added to hydrogen powered vehicles to form comprehensive energy stations.
The combination of green hydrogen and chemical industry: Chemical industry requires continuous hydrogen supply, and standalone photovoltaic hydrogen production is not suitable for independent operation due to its intermittency. At present, high-pressure gas storage tanks are used in chemical engineering, which pose safety challenges and high complexity. Solid hydrogen storage can be used for long-term storage, reducing safety pressure.
Electric peak shaving power station: Equipped with solid-state hydrogen storage and fuel cells of over 200MW, it can be used as a peak shaving power station and can provide power for more than 4-5 hours. This type of power station has a large hydrogen storage capacity, such as the new energy base in Zhangjiakou, China, which is designed to release over 50 tons of hydrogen per day. This application is very suitable for solid-state hydrogen storage. Based on an estimated storage time of more than a week, the unit cost of solid-state hydrogen storage can be as low as 1.0 yuan/wh, slightly lower than the current lithium battery system price range of 1.1-1.2 yuan/wh. However, compared to lithium battery systems, the long-term energy storage advantages of solid-state hydrogen storage systems are more obvious in terms of safety.
Emergency power supply: applied in industrial and commercial areas such as data centers, hospitals, and communities.
Introduction to Solid-state Hydrogen Storage Tank Products
Compared with high-pressure gaseous hydrogen storage methods, solid-state hydrogen storage tanks have the advantage of safety and reliability, with lower equipment requirements. At present, the mainstream solid-state hydrogen storage tanks are mainly composed of solid-state hydrogen storage materials, stainless steel/aluminum shells, gas ducts, filters, heat dissipation fins, valves, and heating/cooling pipelines. Since the pressure of solid-state hydrogen storage tanks is generally lower than 5MPa, there is no need for costly high-pressure valves.
The cost of solid-state hydrogen storage tanks is mainly affected by factors such as scale, shell materials, and hydrogen storage alloys, with different processes and significant cost differences among different companies. According to data from the Research Institute of Industry and Technology, the current cost of solid-state hydrogen storage devices is about 8000 yuan/kgH2, while the cost of metal hydride solid-state hydrogen storage tanks produced by Jingxiao Technology is about 1200 yuan/L. The current solid-state hydrogen storage device is in the early demonstration stage, and in the future, with the expansion of production line scale and the improvement of automation level, manufacturing costs are expected to be significantly reduced. Meanwhile, the hydrogen storage material in the failed hydrogen storage tank can be recycled, further reducing manufacturing costs.
Industrialization process of solid-state hydrogen storage tanks
A series of solid-state hydrogen storage tank products developed by Youyan Industrial Research Institute cover various specifications such as portable, large capacity, and fixed, with a capacity range of 0.1-1000Nm3, and are in a leading position in the industry. Haoyun Jinneng's solid-state hydrogen storage tank products can achieve rapid and high-capacity hydrogen absorption and release, with a working pressure below 3MPa, providing convenience for various application scenarios. At present, domestic enterprises producing solid-state hydrogen storage tanks include Haoyun Jinneng, Youyan Industrial Research Institute, Asus Energy, Antai Chuangming, Yong'anxing, Hydrogen Maple Energy, Nianxiao Technology, and Asus Energy.
At present, mainstream solid-state hydrogen storage tank manufacturers have products with commercial potential on the market. The hydrogen storage tank developed by Haoyun Jinneng has a maximum capacity of 800L and also has a fast and high flow hydrogen release performance of over 200L/min. The solid-state storage tank developed by the Research Institute has been applied to cold chain logistics vehicles and buses in cooperation projects with Yunfu Feichi, Jiahua Lidao, and others. The solid-state hydrogen storage bottle developed by Antai Chuangming is applied to two wheeled vehicles, with a range of up to 80km; The magnesium alloy solid hydrogen storage transport vehicle developed by Hydrogen Maple Energy is equipped with 14 hydrogen storage tanks, which can achieve a hydrogen transportation capacity of 1.2 tons. The production line of solid-state low-pressure hydrogen storage bottles in Yong'an has achieved large-scale production.
Policy: Multi-departmental supports for the development of the hydrogen energy industry
After hydrogen energy was first included in the government work report in March 2019, multiple departments such as the State Council, National Development and Reform Commission, and National Energy Administration have successively issued policies to support and regulate the development of the hydrogen energy industry, mainly including the technical route for hydrogen energy development, hydrogen infrastructure construction, and the development of fuel cell vehicles.
The landing of three major hydrogen fuel cell "demonstration city clusters" to promote cross regional development of hydrogen energy
In August 2021, the Ministry of Finance, the Ministry of Industry and Information Technology, the Ministry of Science and Technology, the National Development and Reform Commission, and the National Energy Administration officially issued the Notice on Launching the Demonstration and Application of Fuel Cell Vehicles, declaring Beijing Tianjin Hebei, Shanghai, and Guangdong as the three major demonstration cities for hydrogen fuel cell vehicles in China, with a demonstration period of four years. The country will adopt a "reward instead of compensation" approach to provide rewards based on the completion of the goals of demonstration city clusters. The implementation of the "Demonstration City Cluster" will accelerate the process of independent and industrialized key core technologies of fuel cells, help explore the commercialization model of hydrogen energy and the establishment of fuel cell industry policies, and promote the coordinated development of hydrogen energy across provinces and regions.
Multiple provinces and cities have released targets for the construction of the hydrogen energy industry
Twenty provinces across the country have publicly released their hydrogen energy plans until 2025. Based on the policies introduced by various provinces and cities in China, the total number of hydrogen fuel cell vehicles and refueling stations planned by the twenty provinces will exceed 100000 and 1300 respectively. The total hydrogen energy industry scale of the twenty provinces will exceed one trillion yuan by 2025.
Market prospect for Hydrogen Fuel Cell Vehicles
From the perspective of global hydrogen fuel cell vehicle ownership, it has achieved rapid growth in recent years, from 24000 vehicles in 2019 to 67500 vehicles by the end of 2022, with a CAGR of 41%; From the perspective of China's situation, by the end of 2022, the number of hydrogen fuel cell vehicles in China has reached 12300, accounting for approximately 18.2% of the global proportion.
From the perspective of global sales of hydrogen fuel cell vehicles, a total of 17926 vehicles were sold in 2022, of which China achieved sales of 3367 vehicles, accounting for 18.8%. With the scaling up of fuel cell system production and the localization of core components of fuel cell stacks, costs have decreased. Guided by the policy of having more than 100000 fuel cell vehicles in 2025, we expect the production and sales of hydrogen fuel cell vehicles in China to rapidly increase in the coming years.
Summary
Solid-state hydrogen storage is an emerging technology in the hydrogen storage process, which has advantages such as high safety, high volume hydrogen storage density, fast hydrogen charging and discharging, and convenient transportation compared to high-pressure gas energy storage and low-temperature liquid hydrogen storage. It has been highly valued by the industry. At present, the mainstream solid-state hydrogen storage route is metal hydrides, including magnesium based, titanium based, vanadium based, rare earth based, and composite hydrogen storage alloys.
The application prospects of solid-state hydrogen storage technology are broad. 1) In the field of onboard hydrogen storage, with the promotion of hydrogen fuel cell vehicles and the decrease in the cost of onboard solid-state hydrogen storage systems, the market space for solid-state hydrogen storage systems will open up. We expect the market size of onboard solid-state hydrogen storage bottles to exceed 10 billion yuan by 2030; 2) In the hydrogen refueling station process, solid hydrogen storage does not require a compressor or liquefaction device compared to high-pressure gaseous and liquid hydrogen storage to complete hydrogen charging. The construction cost of the hydrogen refueling station is relatively low and has good economy. We estimate that the overall cost of the current solid hydrogen storage and refueling station is about 8 million yuan. We predict that the cumulative new investment in the construction of solid hydrogen storage and refueling stations from 2022 to 2026 will increase by about 1.43 billion yuan, By 2025/2026, the newly added investment amounts will be 450/530 million yuan respectively; 3) In other fields, such as distributed energy supply, backup power supply for communication base stations, power peak shaving power stations, etc., hydrogen storage has a larger storage scale and longer storage time, which can meet the requirements of long-term and high-capacity energy storage. At the same time, solid-state hydrogen storage has strong safety and high transportation flexibility, and has a wide range of applications in the field of long-term energy storage.
