Super capacitor battery boosts pure electric bus

In recent days, the "Super Energy Block" that allows buses to run out for 200 kilometers has been successfully developed in Tianjin. After tens of thousands of tests, such as rapid charge and discharge, and a test temperature of minus 40 degrees Celsius to 70 degrees Celsius, this new type of power supply high-energy nickel-carbon supercapacitor overcomes the shortcomings of severe battery life caused by rapid charge and discharge of the power battery, increasing the number of pure electric vehicles. A more realistic approach to energy storage technology path selection.

There are many benefits

Supercapacitors, also known as electrochemical capacitors, are a new type of energy storage device developed in the 1970s and 1980s. As a power source between a conventional capacitor and a battery and having special properties, the supercapacitor mainly uses an electric double layer structure composed of an activated carbon porous electrode and an electrolyte to obtain a large capacity, and thus is different from a conventional chemical power source. It is called "super" because it stores energy in the separated charge. The larger the area for storing the charge and the denser the separated charge, the larger the capacitance.

Due to its large surface area and very small charge separation distance, supercapacitors have surprising electrostatic capacitance compared to conventional capacitors. At the same time, because its energy storage process is reversible, supercapacitors can be repeatedly charged and discharged hundreds of thousands of times, and have the advantages of large power density, large capacity, long service life, maintenance-free, economical and environmental protection.

Industry experts said that for lithium batteries, if they are charged and discharged quickly, they will need to be replaced within 1-2 years of use. The high prices make consumers discouraged. In addition, the instantaneous energy density transmission of lithium batteries cannot meet the demand for new energy passenger cars, and it is impossible to promote the full-load operation of motors in the shortest possible time. These are all important factors that have caused the current commercialization of pure electric vehicles.

In contrast, the supercapacitor has a longer life, a shorter charging time, and there is no pollution caused by the chemical reaction and memory problems of the battery. At the same time, high-power supercapacitors are of great importance for the start-up, acceleration, and uphill driving of pure electric vehicles: they provide high-power currents when electric vehicles are started and climbed; they are fast when the electric vehicles are running normally. Charging; Rapid storage of high current generated by the generator when the electric vehicle is braked, which can reduce the limitation of charging the battery with high current by the pure electric vehicle, thereby greatly prolonging the service life of the battery and improving the practicality of the pure electric vehicle. All are well suited to the technology and application requirements of pure electric vehicles. Tian Zhaowu, an academician of the Chinese Academy of Sciences, believes that supercapacitors are ideal high-power suppliers for pure electric vehicles as opposed to batteries.

The former director of the National Energy Administration, Zhang Guobao, also stated at a forum held before that that there are still many problems to be solved in the battery technology of pure electric vehicles; however, the capacitors are charged quickly, and there should be similar supercapacitors in the development direction of electric vehicles. Technical route.

It is understood that there are three main types of power battery technology: the lowest is a lead-acid battery, and the pollution is serious. It is only used for electric bicycles; the lower gear is a nickel-metal hydride battery, but the price is expensive and the cruising course is short; followed by lithium iron phosphate. The battery has a longer cruising range but is more expensive. It can travel 100-120 kilometers on a single charge, which is currently used by most domestic electric vehicles.

Technology leadership with commercialization

In view of the importance of supercapacitors, many developed countries have attached great importance to them and have been focusing on strategic research and development projects. China's 863 plan has also included the development of super capacitors for electric vehicles in its development plan.

Tian Zhaowu stated that under the premise of lower material costs and production costs and higher specific energy and safety, China has designed a new type of supercapacitor with independent intellectual property rights. The new supercapacitors can be charged and discharged at a high rate of ten seconds, with a single charge and discharge energy density. They do not involve changes in the solid phase during charging and discharging, they are excellent in cycle performance, they have a long life, and there is no risk of burning and explosion. Electrochemically active materials have a large choice, and can be appropriately selected for an electrochemically active material that is rich in resources, environmentally friendly, and easily recoverable, has a simple structure, does not require a large surface electrode, does not require solid-phase formation steps, and has low material cost and manufacturing cost. This can greatly reduce the price of pure electric vehicles.

It is understood that in terms of super capacitor technology research, China has not lost ground. The ultracapacitor researched and developed independently by Harbin Jurong Co., Ltd. was evaluated by the 17th International Electric Vehicles Annual Meeting (EVS-17) as being equivalent to the current internationally most advanced supercapacitor and Russian intellectual property worth US$200 million. At present, the ultra-large capacitance VC series products of Harbin Jurong Co., Ltd. are manufactured using various domestic mature technologies to be optimized and combined, with mature technology foundation and industrial foundation. After several years of operation tests, product performance indicators fully meet the design requirements and have been listed in the National 863 Program and exported to the United States, Canada and other countries.

Super capacitor buses manufactured by companies such as Shanghai Aowei Technology Development Co., Ltd. have passed a series of rigorous tests including safety inspections abroad and are currently exported to many countries and regions. At the 7th International Forum on Energy-saving and New Energy Vehicle Innovation and Development held earlier this year, Aowei Technology displayed 60 supercapacitors contained in newly-launched super-capacity buses. The new type of energy storage device replaces the traditional battery. The capacitor car uses the passengers' pick-up and drop-off time to complete the fast charging in 30 seconds to 3 minutes during the operation. The charging is full-loaded (with air conditioning) for 5-8 kilometers and 100 kilometers of consumption. Electricity is less than 100 degrees, and the energy consumption cost is 1/3 of ordinary fuel vehicles. It is understood that Shanghai's No. 11 and No. 26 routes have used commercial inorganic supercapacitors as the only power source. The commercialization of nearly 100 sets of supercapacitors has been operating for the longest time for nearly five years. It is in good condition and has never been a major accident.

Bus or its "home"

As a new type of energy storage device, super capacitors have filled the gap between the traditional electrostatic capacitors and chemical power sources. Industry experts said that with the in-depth research on electric vehicles, the advantages of applying ultracapacitors in this area will become more and more obvious, and the low cost will determine its significant economic benefits. The market prospect is very broad. However, Jia Xinguang, a well-known car commentator, said that the supercapacitor's capacity is limited and its size is huge. Shanghai's existing supercapacitor buses need to be charged for two or three stops and have a battery life of only a few kilometers, making it difficult to use them in cars.

Experts said that under the same weight, the super capacitor's driving range is only 1/3 of the lead-acid battery, which means that relying on the super capacitor to provide strong power to the vehicle but not lasting, must be charged frequently in a short time, which is for the route and Obviously, it is not suitable for private passenger vehicles with complicated driving conditions.

However, as the bus line station is fixed and unchanged, as long as the super capacitor electric bus charging station can be established at the docking station or on the appropriate place on the line; the bus vehicle running is relatively stable, to meet the super capacitor for tilt angle Limitation requirements. The charging time of the super capacitor is very short, so it is possible to use the time for the bus to enter the station to charge without affecting the passenger's riding experience. In addition, the investment to build a supercapacitor bus charging station is much lower than building a refueling or refueling station.

Experts said that the supercapacitor industry is still in its infancy, but its use determines its strategic value. If the government introduces a strong industrial support policy to promote the development of the upstream and downstream industrial chains of supercapacitors, there will be great room for future development.