In recent years, with the gradual improvement of environmental awareness and the continuous emergence of energy crisis, new energy materials have gradually become the focus of people’s attention. New energy materials refer to materials that can be used to manufacture new energy fields such as solar cells, wind turbines and electric vehicles. These materials can not only improve the efficiency of energy utilization, but also reduce environmental pollution, which is of great significance to the current society and the sustainable development of the future.
1.Photovoltaic Power Generation Materials Industry
From upstream to downstream, the photovoltaic power generation industry chain mainly includes polysilicon, silicon wafers, battery cells and battery modules. In the industry chain, from polysilicon to battery modules, the technical threshold of production is getting lower and lower, and accordingly, the number of companies is also increasing.
\Materials that can be used as solar cell materials include single-crystal silicon, polycrystalline silicon, amorphous silicon, GAAS, Gaara, INP, CDS, CD, and more. Single-crystal silicon, GAAS, and INP are used. Single-crystal silicon, polycrystalline silicon, and amorphous silicon are produced on the ground, with others still in development.
Although the constituent materials of photovoltaic power generation systems vary, all components include several layers of materials from the light-facing side to the backlight side. The electricity upstream of solar power generation materials is silicon ore, and the members of silicon ore, metal silicon to polycrystalline silicon are the current links of the solar power industry chain.
2. Solar Thermal Power Generation Materials
Solar thermal power generation has ushered in a new wave of development with its advantage of built-in energy storage. Solar thermal power stations have a wide range of insulation and high quality requirements for insulation materials. In the current mainstream tower and trough solar thermal projects, insulation materials are mainly used in four parts: the concentrating heat collection system, heat exchange system, heat storage device and steam turbine generator. At present, the insulation materials used in solar thermal power generation systems mainly include ceramic fiber products, rock wool insulation felt, aluminum silicate board, magnesium silicate board, aerogel, etc.
Ceramic fiber is expected to become the preferred insulation material for solar thermal power stations, fully benefiting from the growth of the solar thermal power generation industry.
3. Wind Power Generation Materials
Wind turbine blades have a trend of becoming larger and lighter. The trend of larger and lighter blades promotes the upgrade of blade materials. Since large-sized blades need to reduce weight, the penetration rate of lighter and stronger materials such as carbon fiber in wind turbine blades is also continuously increasing.
The main raw materials of wind turbine blades include resin matrix materials, reinforcement materials, sandwich materials and structural adhesives. According to the “Application and Development of Composite Materials in Large Wind Turbine Blades”, Raw material costs account for 75% of the total cost of wind turbines, with the main raw material costs being matrix materials, reinforcements and sandwich materials. Among them, resin matrix materials account for 33% of the raw material costs of wind turbine blades, sandwich materials account for 25%, and reinforcement materials account for 21%.
Glass fiber or carbon fiber are main reinforcement materials used in wind turbine blades:
(1) Glass fiber is a new type of inorganic non-metallic material with excellent performance, good insulation, high mechanical strength, light weight, high strength, high temperature resistance, corrosion resistance and other characteristics.
(2) Carbon fiber is a filamentous carbon material known as “black gold” in the material area. It is a basic new material with many excellent properties and broad application prospects. The performance characteristics of high specific strength, high specific modulus and low specific gravity make the composite material with carbon fiber as reinforcement have excellent reinforcement and weight reduction effects. In addition, the good chemical stability, thermal stability and electrical properties such as corrosion resistance, high temperature resistance, low expansion coefficient and electrical conductivity make carbon fiber able to be used in harsh working conditions such as high pressure, high temperature, high humidity, high cold and high corrosion.
4.Electrochemical Energy Storage and Power Battery Materials
The battery industry chain mainly include upstream battery raw materials, midstream battery cell module manufacturers or downstream application fields. Upstream raw materials are divided into basic raw materials (including various metal and non-metal raw materials) and battery raw materials (including cathode materials, anode materials, battery separator and battery electrolyte, etc.). Midstream is a manufacturer of battery cell modules that use upstream materials to produce lithium-ion battery products from a variety of specifications and capacity. Downstream applications include power fields, consumer electronics products and energy storage fields.
Cathode Materials
In the field of power batteries, ternary materials and lithium iron phosphate are currently commonly used positive electrode materials. Their differences in physical and chemical structures lead to differences in battery performance and different application fields.
Lithium iron phosphate and ternary materials each have their own advantages and are widely used in different application scenarios. The low cost, high safety and long life of lithium iron phosphate make it suitable for scenarios with low energy density requirements but high safety and life requirements, such as commercial vehicles and energy storage. In recent years, with the improvement of battery group technology, the insufficient energy density of lithium iron phosphate has been improved, and its cost and safety advantages have made it more and more widely used in the field of passenger cars.
The high specific energy advantage of ternary materials is suitable for scenarios that require high energy density and customer experience, such as the field of passenger cars. Increased nickel content increases energy density significantly. High nickel ternary is mainly used in high-end new energy passenger cars with long battery life, such as Tesla Model 3 long-range version, Weilai ES6, Xiaopeng P7, etc., Meanwhile, Medium size nickel’s star are mainly used in new energy transports, low energy transport.
With the transformation driven by the new energy vehicle market, the installed capacity of power batteries in my country has steadily increased, and the development of power batteries has gone through two stages.
- In the first stage (2016-2019), a policy of high energy density was implemented, and ternary materials dominated the market due to their high specific energy performance;
- In the second stage (2020 to date), the policy declined, and lithium iron phosphate batteries began to counterattack with their cost-effectiveness advantages, and officially surpassed ternary materials in July 2021.
The reasons for the counterattack of lithium iron phosphate include three aspects: in terms of policy, the decline in subsidies has led to increased cost pressure, and lithium iron phosphate batteries have gained obvious cost-effectiveness advantages at low cost; the new national standard safety requirements have been increased, and the natural safety advantages of lithium iron phosphate have become more prominent; in terms of supply, new grouping technology has driven the increase in lithium iron phosphate energy density and driven the growth in shipments; in terms of demand, the explosive growth in lithium iron phosphate battery shipments has been driven by vehicle demand, such as BYD Han EV, iron-lithium version Model 3/Y, etc.
Lithium iron manganese phosphate is the upgrade direction of lithium iron phosphate, and it is not suitable as the main material of the positive electrode in the short term. Lithium iron manganese phosphate is a combination of lithium iron phosphate and lithium manganese phosphate, inheriting the high safety and stability of lithium iron phosphate.
At the same time, it can work within the stable electrochemical window of the organic electrolyte system, so that its energy density can be increased by about 10~15%, which is also the biggest advantage over lithium iron phosphate. However, lithium iron manganese phosphate has a low conductivity, and manganese elements will dissolve, resulting in poor charging and discharging capacity and poor cycle life. Therefore, it is not visible as the main material of the positive electrode in the short term. Although the market share of lithium iron phosphate has recovered, high-nickel ternary is still the mainstream in the field of passenger cars.
At present, NCM523, which has the largest market share, is showing a downward trend, and the market share of low-nickel ternary is being compressed year by year. On the contrary, the share of high-nickel NCM811 continues to increase. At the same time, some companies are upgrading their technology in the fields of 9-series high-nickel, NCMA and even cobalt-free high-nickel, but they are still iterations within the high-nickel system. For NCA, due to the high technical barriers, domestic companies occupy a smaller share of the market.
It is expected that the market share of lithium iron phosphate will continue to pick up in the next two years, and the proportion is expected to stabilize between 50% and 60%, but in the entire power battery market, especially in the field of passenger cars, high-nickel ternary will still occupy an important position.
It is expected that ternary or lithium iron phosphate will coexist for a long time in the future. Lithium iron phosphate will take advantage of its cost-effectiveness and safety advantages to occupy a place in the energy storage, commercial vehicle and medium and low-range passenger car markets, while high-nickel ternary will expand its share in the medium and high-range passenger car market with its high energy density advantage. In the new energy vehicle market, high, medium and low-end passenger cars have different sensitivities to various indicators, and graded consumption will be achieved.
The high-range version (≥600km) is equipped with high-nickel ternary; the medium-range version (400＜x＜600km) is equipped with medium-nickel ternary; the entry-level/low-range version (≤500km) is equipped with lithium iron phosphate. However, due to differences in factors such as vehicle positioning, power performance, fast charging performance and drag coefficient, differences in power battery selection still exist among various models.
5.Hydrogen Storage Materials
Hydrogen energy is a very important part of my country’s new energy strategy. Simply put, most of the places where the power grid reaches are power batteries, but in places where the power grid cannot cover, such as rivers, lakes, seas, mountains, Gobi, and cold areas, hydrogen fuel cells will dominate in the future.
Hydrogen is the fuel with the highest energy density on the earth, with a combustion calorific value of 142 kilojoules per gram, which is more than twice that of natural gas and gasoline, and more than five times that of alcohol. Hydrogen energy has become an important part of the energy development of various countries due to its abundant natural reserves, clean and non-toxic, high calorific value and good recyclability. It has also become an important way for the world to respond to climate change and an important direction for energy transformation.
As the main carrier of hydrogen energy, the development of hydrogen production, storage, transportation and application technology and equipment is the key to promoting the development of the hydrogen energy industry. However, the efficient storage of hydrogen has always been difficult to achieve due to the limitations of hydrogen’s low density and high activity physical and chemical properties. Therefore, the “storage and transportation” of hydrogen is a bottleneck problem in the hydrogen energy industry chain.
In the actual application of hydrogen storage, safety and high-density storage are the most important issues, followed by economy and convenience. Solid-state hydrogen storage has the characteristics that are closest to solving these problems, so it can provide an important solution for the following reasons:
First, it has the highest volumetric hydrogen storage density. As an example, its volumetric hydrogen storage density allows 110 kg M-3, achieving a hydrogen density of 1191 times under standard conditions, achieving a high-pressure hydrogen storage of 70 MPa and a density of 1.55 times that of hydrogen liquid.
Second, it has good hydrogen storage safety. Hydrogen bearing tanks are easy to seal and can store hydrogen at room temperature and pressure. In the event of an emergency, even if a hydrogen leak occurs, the storage tank can automatically reduce the hydrogen leakage rate and leakage amount, thereby winning precious time for taking safety measures. Solid-state hydrogen storage is essentially one of the best solutions to the primary problem of hydrogen storage, and can provide strong support for the high-density and high-safety storage and transportation of hydrogen energy.
Alloy hydrogen storage materials
Metal hydride hydrogen storage materials have been widely used, including rare earth series (such as LaNi5), Ti-Zr-Mn series, titanium iron series (such as TiFe), magnesium series and titanium/zirconium series hydrogen storage alloys. These materials can effectively overcome the shortcomings of high-pressure gaseous and low-temperature liquid hydrogen storage methods, and have the characteristics of large volume hydrogen storage density, easy operation, convenient transportation, low cost, high safety, etc., which are particularly suitable for hydrogen application sites with strict volume requirements.
Although solid-state hydrogen storage is still in the early stages of research and development and demonstration, in recent years buses, trucks, refrigerated trucks, backup power supplies, etc. Solid hydrogen storage has been reached as an energy supply. In 2022, the number of solid-state hydrogen storage projects has exceeded double digits.
