Supercapacitors, also known as electrochemical capacitors or electrochemical supercapacitors, belong to the field of core electronic components. They are power-type energy storage devices that effectively make up for the power shortcomings of energy-type energy storage devices such as lithium-ion batteries. Compared with traditional capacitors and secondary batteries, supercapacitors have a higher ability to store charge. Their common structure is an electric double-layer structure, which endows them with many unique advantages.
High Power Density: Supercapacitors have extremely high power density, enabling instantaneous high-intensity energy output, which is suitable for application scenarios requiring frequent and large-scale charging and discharging. For example, in electric motors and ship propulsion, traditional chemical batteries are limited by the rate of chemical reactions, unable to achieve such rapid discharge processes and difficult to meet these special needs, while supercapacitors can easily handle them.
Long Cycle Life: They can undergo extremely frequent charge-discharge cycles, and their performance hardly degrades with the increase in the number of cycles. Ordinary chemical batteries have a relatively short cycle life and need to be replaced frequently, while supercapacitors have a cycle life of hundreds of thousands of times, or even up to one million times. The supercapacitors independently developed by CRRC have a cycle life of one million times, which greatly reduces the use cost and maintenance frequency.
Rapid Charge-Discharge Capability: Supercapacitors work based on electric-electric double-layer storage. The charging and discharging processes are realized through the migration of ions between the electrolyte and the electrode, so the charge-discharge speed is very fast. They can complete charging and discharging in a few seconds or milliseconds, while traditional batteries take a longer time. This rapid charge-discharge characteristic makes supercapacitors the first choice in short-term high-power devices.
High Energy Storage Density: Although the energy storage density of supercapacitors may be inferior to that of lithium-ion batteries and lead-acid batteries, due to their ability to release a large amount of stored energy in an extremely short time, they perform excellently in certain application fields, especially in occasions requiring short-term high power and low total energy. Their energy density is generally 4-10 Wh/kg, and with the development of science and technology, their performance in energy density is constantly improving.
Wide Operating Temperature Range: Supercapacitors have a wide operating temperature range, with the minimum operating temperature reaching -55°C, and they can generally work normally in the temperature range of -40°C to 70°C, adapting to various harsh environmental conditions. This characteristic gives them great advantages in applications in some extreme environments, such as stable operation in power equipment in cold regions and outdoor engineering machinery.
Environmental Friendliness: The chemical substances used in supercapacitors are usually much more environmentally friendly than those used in traditional batteries and capacitors. They do not contain harmful substances and cause no pollution to the environment. Moreover, their reusability conforms to the modern concept of green environmental protection, and they are receiving more and more attention in industrial production.
High Energy Efficiency: Since supercapacitors have no internal chemical reactions, their energy conversion is more efficient compared to batteries. Different from the energy conversion process of batteries, supercapacitors can convert more energy into electricity, which is more obvious in high-power applications, meaning less energy is wasted in energy storage or conversion.
Low Impedance: Supercapacitors have the characteristic of low impedance. When a supercapacitor is fully discharged, it will show a small resistance characteristic. However, this also means that if there is no restriction, it will draw the possible source current, so a constant current or constant voltage charger must be used. At the same time, low impedance allows it to output large currents and quickly absorb large currents.
Rated Voltage: The rated voltage range of supercapacitors is relatively wide, with common specifications such as 2.7V-3.0V and 16V-160V. Different rated voltages can meet various application needs.
Rated Capacity: Its rated capacity has a large span, ranging from 350F-9500F, and there are also different capacity options such as 5.8F-165F. A larger rated capacity can store more charge and provide more lasting energy support for equipment.
Energy Density: The energy density is generally 4-10 Wh/kg. Although there is still a certain gap compared with some energy-type energy storage devices, in occasions requiring high-power output, the speed and efficiency of energy release make up for this deficiency.
Power Density: The power density can reach 14-37 kW/kg, which enables supercapacitors to provide strong power in a short time, meeting the needs of high-power applications.
Cycle Life: As mentioned earlier, the cycle life of supercapacitors is very long, up to 1 million times, which is an important advantage distinguishing them from traditional batteries, greatly improving their reliability and economy in use.
Power Energy Field: In wind power generation, supercapacitors can provide backup power for wind power pitch systems, ensuring that the pitch systems can work normally when the wind is unstable or faulty, and guaranteeing the safe operation of wind turbines. At the same time, they can also provide primary frequency modulation energy storage for power generation systems, improving the stability and power quality of the power system. In power frequency modulation, supercapacitors can quickly respond to changes in grid frequency, perform charge-discharge regulation, and suppress grid fluctuations.
Rail Transit Field: The supercapacitors independently developed by CRRC are suitable for energy storage systems with second-level to minute-level high-power output in the rail transit field. During the start-up and braking processes of rail transit vehicles, supercapacitors can quickly absorb and release energy, realizing energy recovery and reuse, reducing energy consumption, and at the same time reducing wear on traditional braking systems, extending the service life of equipment.
Road Traffic Field: In passenger cars, supercapacitors can provide power sources for power compensation, start-stop, electromagnetic suspension, etc. When the car starts, supercapacitors can instantly provide high power to help the car start quickly; when braking, they can recover energy to improve energy utilization efficiency. In addition, in the field of engineering machinery, supercapacitors can be used as power compensation power sources to meet the high-power needs of engineering machinery during work and improve the working efficiency of equipment.
Industrial Energy-Saving Field: In some industrial equipment, such as electric motors and industrial robots, the rapid charge-discharge characteristics and high power density of supercapacitors can meet the energy needs of equipment during frequent start-stop and high-power operation, reduce the impact of equipment on the power grid, and achieve the purpose of energy saving and consumption reduction. At the same time, supercapacitors can also play an important role in some industrial production links that require short-term high power.
Electronic Communication Field: In electronic communication equipment, supercapacitors can be used as backup power sources to ensure that the equipment can continue to work normally for a period of time in case of sudden power outages, ensuring the continuity of communication. Their rapid charge-discharge characteristics can also meet the needs of electronic communication equipment for rapid energy supply.
Medical Equipment Field: In medical diagnosis and treatment equipment, such as CT scanners and nuclear magnetic resonance equipment, supercapacitors can provide high-power energy support when the equipment starts, ensuring that the equipment can start quickly and run stably. At the same time, their long life and high reliability can meet the strict requirements of medical equipment for stability and safety.
Application Promotion Methods: mainly through sales and cooperation. Enterprises can directly sell supercapacitors to customers in various application fields, and also cooperate with other enterprises to jointly develop and promote related application products. For example, cooperating with automobile manufacturers to apply supercapacitors to the start-stop systems and energy recovery systems of automobiles.
Application Promotion Fields: focusing on promotion in fields such as wind power generation, power frequency modulation, engineering machinery, and passenger cars. In the field of wind power generation, providing backup power for wind power pitch systems and primary frequency modulation energy storage for power generation systems; in the field of engineering machinery, providing power compensation power sources; in the field of passenger cars, providing power sources for power compensation, start-stop, electromagnetic suspension, etc. Through promotion and application in these key fields, the advantages of supercapacitors can be fully exerted, and the development of related industries can be promoted.
With the continuous progress of science and technology and the growing demand for energy, supercapacitors have a broad development prospect. Driven by the national dual-carbon strategic goals, supercapacitors, as a green and efficient energy storage device, will be applied in more fields. In the future, the performance of supercapacitors is expected to be further improved, with higher energy density and power density, and the cost will continue to decrease. At the same time, with the continuous expansion of application fields, supercapacitors will complement other energy storage technologies to jointly build a more perfect energy storage and utilization system. For example, in the field of new energy vehicles, the combined use of supercapacitors and lithium-ion batteries can give full play to the advantages of both, improving the performance and range of vehicles. In the construction of smart grids, supercapacitors will also play an important role in improving the stability and reliability of the power grid. In short, supercapacitors will become an important part of the future energy field, making important contributions to promoting the energy revolution and sustainable development.
