1.1 Research background of super capacitors
From the 1870s to the present, the development of super capacitors has gone through many important processes: In the late 1950s, some scientists proposed replacing double-layer electrochemical capacitors made of metal sheets with capacitors made of porous carbon materials, and It has been proven by practice. In other words, electrochemical capacitors have made rapid progress at this time. The world’s first commercial super capacitor came out in 1971, which marked that super capacitors have begun to enter the market operation stage; in the 1980s, In the 1990s, due to the introduction of pseudocapacitive electrode materials, the energy density of super capacitors has been greatly improved, reaching a farad level that has never been reached before. Only then did the so-called electrochemical capacitors be called true super capacitors. Name; In the 1990s, the development prospects of super capacitors were valued by Western developed countries, and they have proposed major projects related to it.
In 1879, Helmholz discovered the properties of double-layer capacitance and proposed the concept of electric double layer. However, the use of double-layer super capacitors for energy storage has only been in recent decades. In 1957, Becker (General Electric Co.. GE) proposed using capacitors with a specific capacity close to the battery as energy storage components. In 1968, Sohio (The Standard Oil Company) used high specific surface area carbon materials to produce electric double layer capacitors. In 1978, Japan’s Osaka Company produced gold capacitors, which were the earliest commercialized and mass-produced carbon electric double layer capacitors. In 1979, Nippon Electric Company, Limited began producing supercapacitors and used them in starting systems for electric vehicles. In 1980, Japan’s Panasonic Corporation studied super capacitors using activated carbon as electrode material and organic solution as electrolyte. After this, super capacitors began to be industrialized on a large scale.
1. Advantages of super capacitors
(1) High capacitance: The capacity of supercapacitors can reach up to several thousand farads, which is thousands of times higher than the capacity of platinum electrolytic capacitors and aluminum electrolytic capacitors of the same volume.
(2) Long cycle life: The charging and discharging process of supercapacitor is divided into two types according to its energy storage mechanism: one is the physical process of electric double layer, that is, there is only the transfer of ions or charges during the charging and discharging process, and no chemical or electrochemical reaction occurs. Another situation that triggers electrode phase change is the electrochemical reaction process. This reaction process has good reversibility and is not prone to phenomena such as crystalline transformation and shedding of active materials that affect the service life. All in all, no matter which of the above processes occurs, the capacitance of the supercapacitor decreases very little, and the number of cycles can reach tens of thousands of times, which is 5 to 20 times the number of cycles of the battery.
(3) Short charging time: Supercapacitors use high current to charge and can be quickly charged in a few seconds to minutes, while batteries require dozens of minutes to charge quickly, and frequent rapid charging will also affect the service life.
(4) High power density and high energy density: While supercapacitors provide a power density of 1000~2000W/kg, they can also output an energy density of 1~10Wh/kg. For this reason, supercapacitors are suitable for applications where short-term high power output is required. The mixed use of supercapacitors and battery systems can form a system with both high power density and high energy density.
energy storage system.
(5) Wide operating temperature range: The operating temperature range of supercapacitors is -40~70°C, while the operating temperature range of general batteries is between -10~50C. (6) Reliable operation, maintenance-free and environmentally friendly: Supercapacitors have a certain ability to resist overcharge and will not have much impact on their work in a short period of time, ensuring the reliability of system operation.
2. Disadvantages of super capacitors
(1) Low monomer working voltage: The working voltage of aqueous electrolyte supercapacitor monomer is generally 0~1.0V. The high output voltage of supercapacitors is achieved by connecting multiple single capacitors in series, and the series capacitors are required to have good consistency. The working voltage of a non-aqueous electrolyte supercapacitor monomer can reach 3.5V, but in actual use the maximum is only 3.0V. At the same time, the purity of non-aqueous electrolytes is high, and it needs to be produced in an assembly environment such as anhydrous and vacuum conditions.
(2) Possible leakage: Although the materials used in supercapacitors are safe and harmless, if the installation location is unreasonable, electrolyte leakage may still occur, affecting the normal performance of the supercapacitor.
(3) Supercapacitors are generally used under DC conditions and are not suitable for use in AC situations.
(4) Higher price: The cost of supercapacitors is much higher than that of ordinary capacitors
Supercapacitors are a new type of energy storage device between traditional capacitors and batteries, with capacities ranging from hundreds to thousands of farads. Compared with traditional capacitors, it has larger capacity, higher energy, wider operating temperature range and extremely long service life; compared with batteries, it has higher power density and no pollution to the environment. . Therefore, supercapacitor is an efficient, practical and environmentally friendly energy storage device. The performance comparison of several energy storage devices is shown in Table 1-2.
Table 1-2 Performance comparison of several energy storage devices
Currently, the indicators used to describe the performance of supercapacitors are:
1) Rated capacity: refers to charging to the rated voltage according to the specified constant current (for example, the charging current specified for super capacitors above 1000F is 100A, and those below 200F is 3A) for 2~3 minutes, and then discharged under the specified constant current discharge conditions. The product of the time until the terminal voltage is zero and the current is divided by the rated voltage value, in farads (F).
2) Rated voltage: the highest safe terminal voltage that can be used. Breakdown voltage, its value is much higher than the rated voltage, about 1.5 to 3 times the rated voltage, the unit is volts (V) 3) Rated current: refers to the current discharged to half of the rated voltage within 5 seconds, the unit is Ampere A)
4) Maximum stored energy: refers to the energy released when discharging to zero at rated voltage, the unit is Joule (J) or Watt-hour (Wh).
5) Energy density: also called specific energy. Refers to the energy given by the capacitor per unit mass or unit volume, in Wh/kg or w·h/L.
6) Power density: also called specific power. It refers to the discharge power of a super capacitor per unit mass or unit volume when it produces half and half electrical/heating effects under matching loads. It represents the ability of the super capacitor to withstand current, and the unit is kw/kg or kW/L.
7) Equivalent Series Resistance (ESR): Its value is related to supercapacitor electrolyte and electrode materials, preparation process and other factors. Generally, AC ESR is smaller than DC ESR and decreases as the temperature rises. Units are ohms (Q).
8) Leakage current: refers to the static loss caused by the internal equivalent parallel impedance when the supercapacitor maintains a static energy storage state. It is usually the current measured after applying the rated voltage for 72 hours, and the unit is Ampere (A).
9) Service life: refers to the length of time when the capacitance of the super capacitor is less than 20% of the rated capacity or the ESR increases to 1.5 times the rated value.
10) Cycle life: A super capacitor experiences one charge and discharge, which is called one cycle or one cycle. The cycle life of supercapacitors is very long, up to more than 100,000 times.
In the development of supercapacitors, the current focus is on liquid electrolyte electric double layer capacitors and composite electrode material/conductive polymer electrochemical super capacitors. The development of foreign supercapacitors is shown in Table 1-3.
Table 1-3 Development of supercapacitors abroad
In terms of the industrialization of super capacitors, the earliest products were products from NEC and TOKIN in 1980 and Panasonic and Mitsubishi in 1987. The nominal voltage of these capacitors is 2.3~6V, with an annual output of millions. In the 1990s, Russian ECOND Company and ELIT produced SC brand electrochemical capacitors with nominal voltages from 12 to 450V and capacitances from 1F to several hundred F, which are suitable for occasions requiring high-power starting power. In general, products from the United States, Japan, and Russia currently occupy almost the entire super capacitor market, and industrialized super capacitors are basically electric double layer capacitors. Some performance parameters of some electric double layer supercapacitor products are listed in Table 1-4.
Table 1-4 Some performance parameters of electric double layer super capacitor products
In my country, Beijing Nonferrous Metal Research Institute, Jinzhou Power Capacitor Co., Ltd., University of Science and Technology Beijing, Beijing University of Chemical Technology, Beijing Institute of Technology, Beijing Jinzhengping Technology Co., Ltd., Army Chemical Defense College, Harbin Jurong New Energy Co., Ltd., Shanghai Ao Wei Technology Development Co., Ltd. and others are conducting research on super capacitors. In 2005, the 863 project “Research on Key Technologies of Supercapacitor Energy Storage Systems for Renewable Energy Power Generation” undertaken by the Institute of Electrical Engineering of the Chinese Academy of Sciences passed expert acceptance. This project completed the research and development of a 300W·h/kW super capacitor energy storage system for photovoltaic power generation systems. In addition, relevant research groups such as North China Electric Power University are studying the application of supercapacitor energy storage system (Super capacitor Energy Storge System, SESS) to the distribution network of distributed power generation systems. But overall, my country’s research and application level in the field of supercapacitors clearly lags behind the world’s advanced level.
When using supercapacitors, you should pay attention to the following issues: 1. Supercapacitors have fixed polarity, and the polarity should be confirmed before use; 2. Super capacitors should be used at nominal voltage because when the capacitor voltage exceeds the nominal voltage It will cause the electrolyte to decompose, and the capacitor will heat up, reduce the capacity, and increase the internal resistance, shortening its life; 3. Due to the existence of ESR, supercapacitors cannot be used in high-frequency charging and discharging circuits: when using supercapacitors in series When there is a voltage balance problem between cells, simple series connection will cause one or several cell capacitors to be damaged due to overvoltage, thus affecting their overall performance.
With the development of power systems, distributed power generation technology has attracted more and more attention. As a necessary energy buffer link in distributed power generation systems, energy storage systems play an increasingly important role. The supercapacitor energy storage system uses multiple groups of supercapacitors to store energy in the form of electric field energy. When energy is urgently lacking or needed, the stored energy is released through the control unit to accurately and quickly compensate for the active and reactive power required by the system. work, thereby achieving balance and stable control of electrical energy. In 2005, a 450kW supercapacitor energy storage device was built in California, USA, to reduce fluctuations in the power delivered by a 950kW wind turbine to the grid. In addition, energy storage systems can also play an important role in improving the power quality of power system distribution networks. Through the inverter control unit, the reactive power and active power provided by the supercapacitor energy storage system to users and the network can be adjusted to achieve the purpose of improving power quality.
In the 35kV substations and 10kV switch stations built in my country from the 1960s to the 1980s, the operating mechanisms of most high-voltage switches (circuit breakers) are electromagnetic operating mechanisms. The corresponding DC system is equipped in the power distribution room of the substation or distribution station, which is used as the DC power supply for opening and closing operation, control and protection. These DC power equipment are mainly capacitor energy storage silicon rectifier opening and closing devices and DC panels partially composed of batteries. Capacitor energy storage silicon rectifier opening and closing devices were widely used at that time due to their simple structure, low cost, and low maintenance. However, there was a fatal flaw in actual use: poor reliability of accident opening and closing. The reason is that the capacity of electrolytic capacitors for energy storage is limited and the leakage current is large. Although DC panels composed of batteries can store a large amount of electrical energy and have become necessary devices in some important transformation and distribution stations, due to their extremely high operating costs and short service life, these devices can only be used at the 110kV level. It is difficult to promote the use of substations.
Supercapacitors make it possible to solve the above problems with their ultra-long service life, frequent and fast charge and discharge characteristics, and cheap price. If two 0.85F, 240/280V supercapacitors are connected in parallel, they can completely replace the bulky, frequent maintenance, and polluting battery pack. Since the energy consumption of one closing is only equivalent to 3% of the energy stored in the supercapacitor (70kJ), and this energy can be quickly replenished in the floating charge circuit, it is fully adaptable to continuous and frequent operations, and has extremely high High reliability.
Although many users choose Uninterrupted Power Supply (UPS) as a rescue device for equipment power supply when the grid is out of power or the grid voltage drops instantaneously, UPS is overqualified for instantaneous voltage drops. UPS is powered by batteries and has a long working time. However, due to the shortcomings of the battery itself (requires regular maintenance, short life), the UPS needs to always pay attention to the status of the battery during operation. The duration of power system voltage drops is often very short (10ms ~ 60s), so the advantage of using supercapacitors in this case is obvious over UPS: its output current can rise to hundreds of amps with almost no delay, and the charging speed is very fast It is fast and can store energy within minutes to facilitate the next power failure. Therefore, although the energy storage of the supercapacitor can be maintained for a short time, when it is used for about 1 minute, it has incomparable advantages – 500,000 cycles, no care required, and economical. In Singapore, a dynamic voltage recovery device (DVR) produced by ABB that uses supercapacitor energy storage is installed in a 4MW semiconductor factory to achieve 160ms fault ride-through.
The static synchronous compensator (STATCOM) is one of the main devices of Flexible AC Transmission Technology (FACTS) and represents the new development direction of reactive power compensation technology in the power system at this stage. It can quickly and continuously provide capacitive and inductive reactive power, achieve appropriate voltage and reactive power control, and ensure stable, efficient and high-quality operation of the power system. STATCOM based on double-layer capacitor energy storage can be used to improve the voltage quality of distributed power generation systems. It will gradually replace traditional superconducting energy storage in distributed power generation systems with power levels of 300~500kW. In terms of economics, the cost of an electric double layer capacitor energy storage device of the same capacity is almost the same as that of a superconducting energy storage device, but the former requires almost no operating costs, while the latter requires considerable cooling costs.
For supercapacitors, the direction and focus of future research is: utilizing the high specific power characteristics and rapid discharge characteristics of super capacitors to further optimize the application of supercapacitors in power systems. In addition, under the guidance of my country’s policy of vigorously developing new energy, in the fields of photovoltaic power generation and wind power generation, super capacitors provide favorable conditions for the improvement and development of key equipment with their fast charging and fast discharging characteristics.
1.2 Classification of super capacitors
As a new green energy storage component, supercapacitor has broad application prospects in electric vehicles, distributed power generation systems and other fields. Supercapacitors can be divided into three categories: electric double layer supercapacitors, pseudocapacitors and hybrid supercapacitors according to different energy storage principles.
1. Electric double layer super capacitors
Electric double layer supercapacitors use the interface double layer formed between electrodes and electrolytes to store energy. Electric double layer supercapacitors have made changes in manufacturing materials, such as: activated carbon electrode materials, which are processed with high specific surface area activated carbon materials to make electrodes, carbon airgel electrode materials, which are combined with precursor materials to prepare gels, and then carbonized Activation treatment serves as an electrode. When the electrode and the electrolyte come into contact, due to the action of Coulomb force, intermolecular force or interatomic force, a stable double layer of charges with opposite signs appears at the solid and liquid interface, which is called the interface double electric layer.
Pseudocapacitance, also known as Faraday quasicapacitance in general, refers to the capacitance on the electrode surface or body.
On the two-dimensional or quasi-two-dimensional space in the phase, the active material undergoes under-potential deposition and highly reversible chemical adsorption/desorption or oxidation/reduction reactions occur, thereby generating Faradaic capacitance. Pseudocapacitive super capacitors generally use metal oxide electrode materials and polymer electrode materials. They can be divided into adsorption eagle capacitors and redox eagle capacitors.
3. Hybrid super capacitors
Hybrid super capacitors can be divided into the following 3 types (based on different types of electrode materials):
1) It consists of an electrode with both electric double layer capacitance characteristics and an electrode with pseudocapacitance characteristics, or is composed of two different types of pseudocapacitance electrode materials.
2) Composed of super capacitor electrodes and battery electrodes
3) It consists of the anode of the electrolytic capacitor and the cathode of the super capacitor. The two poles of hybrid supercapacitors generally use “battery-type” materials with high energy density as active materials and “capacitor-type” materials with high power density, so they have the advantages of both.
1.3 Application prospects of super capacitors
Supercapacitors are also called electrochemical capacitors. They have stable performance, specific capacity is 20 to 200 times that of traditional capacitors, and specific power is generally greater than 1000W/kg. The cycle life and storable energy are much higher than traditional capacitors, and they charge quickly. Due to their extremely long service life, they can be used throughout the entire life cycle of the end product. When high-energy batteries and fuel cells are combined with supercapacitor technology, high power density, high energy density characteristics and long operating life can be achieved.
In recent years, high-power supercapacitors have shown a rising industry trend in the fields of electric vehicles, solar energy devices, heavy machinery and other fields. Many developed countries have regarded supercapacitor projects as national key research and development projects. The domestic and foreign markets of supercapacitors are showing a trend. Unprecedented prosperity.
The application of supercapacitors has become increasingly mature and has been widely used in fields such as industry, communications, medical equipment, military equipment, and transportation . From small-capacity emergency energy storage to large-scale power energy storage, from independent energy storage to hybrid energy storage systems with batteries or fuel cells, supercapacitors have shown unique advantages. To sum up, the application directions of supercapacitors can be divided into the following four fields:
1. Main power supply, replacement power supply or backup power supply for low-power electronic equipment
1) Main power supply: Supercapacitors are suitable for use in main power supplies. Typical applications include electric toys, which have the advantages of being small in size, light in weight, high in power density and able to start quickly as the main power supply.
2) Replacement power supply: Supercapacitors are also suitable for use in replacement power supplies. Typical applications include road signs, solar watches, traffic lights and bus stop timetable lights.
3) Backup power supply: Supercapacitors are widely used in backup power supplies. Typical applications include vehicle meters, vehicle fare meters, radio wave receivers and cameras, etc.
2. Hybrid electric vehicles and electric vehicles
The lifespan of supercapacitors is hundreds of times that of electrochemical batteries (storage batteries and potassium-ion batteries, etc.) and does not require maintenance. Therefore, the total cost of supercapacitors applied to electric vehicles is much lower than that of general electrochemical batteries. Currently, countries all over the world are investing the most in developing electric vehicles, of which hybrid electric vehicles (Hybrid Electric Vehicles) are the ones that invest the most. Hybrid electric vehicles use batteries to provide normal operating power for electric vehicles. Supercapacitors are used to supplement power when accelerating and climbing, and ultracapacitors are used to store regenerative energy generated during braking. Therefore, electric vehicles using supercapacitors have the advantages of fast starting, fast acceleration and strong climbing ability.
3.Renewable energy power generation systems and distributed power systems
Supercapacitors can give full play to the advantages of high energy storage density, high power density, long cycle life and no need for maintenance. They can store energy alone or be mixed with other energy storage systems to store energy. Supercapacitors can be combined with solar cells and used in street lights, traffic warning signs, traffic lights, etc. They can also be used in distributed power generation systems, such as wind power stations, hydropower stations, etc. Energy storage through supercapacitors can improve the system. It plays the role of instant power compensation to improve the stability and reliability of the power supply system. This power supply method can well compensate for the unstable and unpredictable output power of power generation equipment.
4. Energy buffer
The energy buffer consists of a supercapacitor and a power converter. It is mainly used in variable frequency drive systems such as elevators. When the elevator accelerates up, the energy buffer supplies power to the DC bus in the drive system to provide the peak power required by the motor. When the elevator decelerates and descends, the energy buffer absorbs the energy fed back by the motor.
Supercapacitors can replace batteries in portable instruments such as driving micromotors, relays, and solenoid valves. It can avoid misoperation due to instantaneous load changes. Supercapacitors can also be used to power camera flashes, allowing the flash to achieve continuous use performance, thereby improving the camera’s ability to continuously shoot. It is applied to camera phones, allowing camera phones to use high-power LEDs. Supercapacitor technology can also be used in mobile wireless communications equipment. These devices often use pulses to maintain communication. Because supercapacitors have strong instantaneous charge and discharge capabilities and can provide high power, they have a wide range of applications in this field. Supercapacitors are almost irreplaceable components in important power systems of many large petrochemical, electronic, textile and other enterprises, especially in transient voltage and current stabilization of high-power systems. In addition, it is also very important for chip companies to consider power fluctuations when selecting sites, and supercapacitor systems can completely solve this problem.
Supercapacitors also play an irreplaceable role in short-term UPS systems, electromagnetic operating mechanism power supplies, solar power car anti-theft, car audio and other systems. In wind power or solar power systems, due to the instability of wind and solar energy, the battery will be repeatedly charged frequently, resulting in shortened life. Supercapacitors can absorb or supplement the fluctuations in electrical energy to solve this problem. Supercapacitors also have huge application value and market potential in electric vehicles, hybrid fuel vehicles and special load-carrying vehicles. As a power source for electric and hybrid vehicles, supercapacitors can be used alone or in combination with batteries. In this way, when the supercapacitor is used as a short-term drive power supply for electric vehicles, it can quickly provide a large current when the vehicle starts and climbs a hill to obtain power to provide powerful power; it can be quickly charged by the battery during normal driving; and it can be quickly charged by the battery during braking. Quickly store the large warm-time current generated by the generator, thereby reducing the restrictions on high-current discharge of the battery by electric vehicles, extending the cycle life of the battery, and improving the practicality of electric vehicles. The application of supercapacitors in the electric moped market is also expanding. The battery on an electric moped has strict charging and discharging current requirements, making it difficult to recover energy instantaneously. Supercapacitors can easily meet these requirements. The supercapacitor supplements the energy of the system when the electric moped is starting, accelerating and climbing, and completely recovers energy during braking to improve system performance.
As one of the key new energy storage products developed in the 21st century, super capacitors are being developed and produced by more and more countries and companies, and their rapid progress is obvious to all. At the 1st International Annual Conference on Electric Double Layer Capacitors and Hybrid Energy Storage held in 1991, the large single capacitor was a capacitor with a capacity of 470F designed and developed by Panasonic, and its voltage was 2.3V. Today, the capacity of single capacitors of the same size produced by Panasonic has exceeded 2000F. At the same time, not only Panasonic, but many companies around the world have begun to enter this field. These companies are mainly engaged in the development of large-scale manufacturing technology and marketing so that capacitor products can be used with portable electronic equipment and pulse power appliances on the market. It can be said that today’s super capacitor market has entered an era of competition: Maxwell’s company in San Diego is the leading manufacturer of large-scale electrochemical capacitors in the United States; PowerStor was developed from the carbon aerogel technology of Lawrence Livermore’s laboratory , and is now quite large-scale; South Korea’s Ness Company has been interested in small energy storage devices since the beginning. Its products have spread throughout the market, from small ones to the largest ones, and have now developed into a company. The company that leads the way in the pulse power performance of electrochemical capacitors; the products of Germany’s Siemens Matsushita also greatly surpass all its previous products. It is a subsidiary of Maxwell and later became EPCOS; recently, as one of the important members of the world’s electrolytic capacitor industry One Japanese chemical company has now officially joined the super capacitor industry-Power System Company founded by Mr. Okamura now has a production line of large-scale products; certain products of Russia’s ECOND Company, ELIT Company and ESMA Company It is also a force that cannot be underestimated in the super capacitor team. Among them, Russia’s ESMA company is the representative of the production of inorganic hybrid super capacitors. In recent years, some companies in our country have also begun to actively get involved in this industry, and have already possessed certain technical strength and industrialization capabilities. Important companies include Jinzhou Fu Company, Beijing Jixing Company, Beijing Hezhong Huineng, Shanghai Aowei Company, Jinzhou Jinrong Company, Shijiazhuang Gaoda Company.
Beijing Jinzhengping Company, Jinzhou Kaimei Company, Daqing Zhenfu Technology, Harbin Jurong Company, Nanjing Jihua Company, Xinzhoubang Company, etc. Among them, Xinzhoubang Company has now become a qualified supplier of the world’s mainstream super capacitor manufacturers, such as the American Maxwell Company, REDI Company and other upstream manufacturers, and has gradually realized batch supply; domestic customers mainly include Beijing Jixing and Beijing Hezhonghui Neng, Jinzhou Kaimei and other companies. Since 2009, the company’s customers and orders have continued to increase, and it is expected to become one of the main suppliers to the world’s mainstream super capacitor manufacturers.
With the application of super capacitors in electric vehicles in recent years, their market has become increasingly broad. The current automotive power battery market is mainly composed of the following four parts: lead-acid batteries are currently mostly used in electric bicycles; metal oxide nickel batteries are expensive and have short driving distance and have no prospects in electric vehicles; potassium iron phosphate batteries are relatively expensive and It has been used in electric vehicles and can travel 100~120km on a single charge. It needs to start the hybrid power of the gasoline engine to extend the mileage; super capacitor power battery is cheap, maintenance-free and has a charge-discharge cycle life of 100,000~500,000 times, maybe Power batteries will soon become the mainstream. Compared with metal oxide nickel batteries/potassium iron phosphate power batteries, super capacitors made of high-purity barium titanate have the advantages of high energy density, high power utilization, safety, and low price. The U.S. Department of Energy first issued a statement in the “Business Daily” in the 1990s, strongly recommending the development of capacitor technology and its application in electric vehicles. At the time, California had enacted a near-term plan for zero-emission vehicles, and these electric vehicles using capacitors were generally considered to be cars that just met that standard. Capacitors are the most potential and most effective technology for realizing the practical use of electric vehicles. The DOE’s announcement has prompted companies such as Maxwell Technologies to enter the field of electrochemical capacitor technology. Fast forward to 2016, and advances in technology have paved the way for the use of electrochemical capacitors to recover regenerative braking energy in hybrid vehicles. These hybrids are now being used in highly hybrid city bus systems.
The electric vehicles of Japan’s Fuji Heavy Industries use a combination device of potassium-ion batteries produced by Hitachi Electric Corporation and energy storage capacitors produced by Panasonic Corporation: Japan’s Honda Corporation has even combined super capacitors with gasoline engines to develop a comprehensive motor booster The system greatly reduces the emissions of the internal combustion engine and can recycle braking energy. By being installed on the passenger car, it greatly reduces the fuel consumption of the gasoline engine and makes it a low-emission energy-saving vehicle: the hybrid electric vehicle developed by Japan’s Toyota Company, whose emissions Compared with traditional gasoline locomotives: CO is reduced by 50%, CO and NO are reduced by 90%, and fuel is saved by half.
In my country, with the official introduction of financial subsidy policies for private purchases of new energy vehicles, market participants pointed out that this will become an opportunity for the further development of super capacitors. In the field of new energy vehicles, super capacitors are usually used in combination with carp-ion batteries. The perfect combination of the two forms a power source with stable performance, energy saving and environmental protection, which can be used in hybrid vehicles and pure electric vehicles. Potassium-ion batteries solve the problem of car charging and energy storage and provide long-lasting power for the car. The mission of the super capacitor is to provide high-power auxiliary power for starting and accelerating the car, and to collect and store energy when the car is braking or running rapidly. Among domestic manufacturers involved in new energy vehicles, many have chosen the technical route of combining super capacitors with potassium-ion batteries. For example, Ankai Bus’ pure electric buses and Haima parallel pure electric sedan MPe use potassium-ion battery/super capacitor power systems. In addition, the technology developed by Shanghai Aowei Technology Development Co., Ltd. to modify ordinary activated carbon into high-purity activated carbon through high technology and make new electrical storage materials for use in super capacitors has been industrialized. The super capacitors they produce are beginning to be used in new energy vehicles.
In the face of ever-expanding market demand, the super capacitor industry is still in its infancy. Existing supercapacitor products still have imperfections. It is necessary to look for new technology solutions that can serve the insufficient functions of existing products, improve product performance, reduce product prices, and broaden product offerings. Application in new fields and strengthening its cooperation with power batteries are the future development trend and direction of super capacitors. In particular, its application in the field of new energy vehicles determines its strategic value and attracts a large amount of manpower and material resources around the world for research and development Some companies in the United States, Japan and other countries are currently in a leading position in the industrialization of super capacitors with their years of development experience and technology accumulation. With the in-depth adjustment of my country’s economic structure, I believe we will eventually discover its value and will successively introduce strong industrial support policies to promote the development of the upstream and downstream industrial chains of this strategic product.