Structure type of electric vehicle energy storage device

Structure type of electric vehicle energy storage device
The most common one is an electric vehicle powered by a pure battery. The energy storage and control of this type of electric vehicle are relatively simple, and the entire vehicle uses a power battery as an energy storage device. The vehicle with this structure is powered by a single power battery. In the division of new energy vehicles, it is called BEV, that is, pure battery to zinc-air battery, etc., all belong to the category of power battery. The battery arrangement of the electric vehicle with this structure is relatively simple, and the battery can be arranged around the vehicle, or can be centrally distributed at the rear, front, bottom or top of Energy Storage Device Parts the vehicle. This structure has strict requirements on the battery. Generally, according to the function and operating conditions of the electric vehicle, a battery with higher specific energy and specific power should be selected. The specific energy affects the driving mileage of the whole vehicle, and the specific power affects the high power of the battery. Discharge performance, thus affecting the acceleration performance and climbing ability of electric vehicles.
In order to solve the problem that a power battery cannot meet the specific power and specific energy at the same time, some electric vehicles use two different batteries, one of which can provide high specific energy and the other can provide high specific energy. power. Two kinds of batteries are used as the basic structure of the hybrid energy source. This structure not only solves the contradiction between specific power and specific energy, but also plays a significant role in the braking energy recovery of the vehicle due to the existence of the larger specific power battery. Effect.
Structure type of electric vehicle energy storage device
In addition to batteries, fuel cells can also be used as energy storage devices. For electric vehicles, fuel cells are equivalent to a small generator. At present, there are many types of fuel cells, and the most common one is hydrogen fuel cells. The principle of the hydrogen fuel cell is to use the reversible electrolysis process. Under specific media and working conditions, hydrogen and oxygen are combined to generate electricity and water. The storage of hydrogen is currently a more troublesome problem. Since the liquefaction pressure of hydrogen is very high and the liquefaction temperature is relatively low, it is difficult for hydrogen to be liquefied, so a high-pressure storage container is required. At present, hydrogen is generally stored in gaseous form in a high-pressure vehicle-mounted hydrogen tank, a small amount is stored in the form of liquid hydrogen or metal hydride, and oxygen can be obtained directly from the air. Although the fuel cell can provide a very high specific energy, it cannot recover the regenerative energy of braking. At present, this structure is basically replaced by a hybrid type.
In order to solve the shortcoming that the fuel cell cannot be used for braking and regeneration, the battery is used together with the fuel cell more often. This can not only absorb part of the excess energy of the fuel cell, but also can absorb the problem of braking regeneration energy.
The hydrogen required for fuel cells is currently not only in the form of hydrogen, but also stored in the form of compressed air, liquid hydrogen or metal hydride, and can be produced by room temperature liquid fuels such as methanol, ethanol or gasoline. This requires the vehicle to have a small reformer to break down methanol, ethanol or gasoline at any time to produce hydrogen for fuel cells.
Structure type of electric vehicle energy storage device
The emergence of supercapacitors has given electric vehicles a new option. Supercapacitors are similar to batteries, but work on a completely different principle. Supercapacitors physically store electrical energy. There are also many electric vehicles that use pure supercapacitors as energy sources to drive electric vehicles. Supercapacitors are devices that physically store electrical energy without chemical reactions, so they can be charged and discharged at a large rate, and are almost unaffected by temperature, with a long service life and relatively simple maintenance. Another obvious advantage of supercapacitors is that they are very good at absorbing the regenerative energy of the vehicle's braking. However, the current use of supercapacitors is limited to a certain extent. Although its specific energy is not low, its available specific energy is not high, and its density is low and occupies a large space. Electric vehicles that use supercapacitors as power sources generally have a short driving range and are mostly used for public transportation.