Battery pack of electric vehicle

Abstract

The invention relates to a battery pack of an electric vehicle, and the battery pack comprises a battery monomer, an air inlet pipeline assembly and air inlet covers; the air inlet pipeline assembly is provided with a plurality of branch ventilating ducts, at least one of the plurality of branch ventilating ducts is bent and roundabout, and each branch ventilating duct is communicated with the corresponding air inlet cover; the interior of the air inlet cover is divided into a plurality of range-extending ventilating ducts and a plurality of independent air inlet areas, the front end of each range-extending ventilating duct is communicated with the corresponding branch ventilating duct, the tail end of each range-extending ventilating duct is communicated with the corresponding air inlet area, at least one range-extending ventilating duct is provided with a bent detour, and the bent detour aims at adjusting the air flowing path. The invention has the beneficial effects that the branch ventilation ducts and the range extending ventilation ducts are arranged, so the flowing paths of each gas are very close, the time of the gas reaching each battery monomer is synchronous, the temperature change of each battery monomer is consistent, and the discharge depth and the service life of the battery pack are improved.

Description

technical field [0001] The invention relates to the technical field of power batteries and energy storage batteries for electric vehicles, in particular to a battery pack for electric vehicles. Background technique [0002] Compared with traditional cars, electric vehicles not only can get rid of dependence on oil, but also have the advantages of no polluting gas emission during use and protection of the urban environment. At present, China's electric vehicles are mainly lithium-ion battery vehicles, and fuel cells, metal lithium batteries and other forms of energy batteries are constantly developing. The battery pack is a key component of electric vehicles, and its quality directly affects the experience of using electric vehicles and the life of the entire vehicle. However, it also faces some development difficulties, such as insufficient safety, many fire accidents, cruising range needs to be improved, battery pack energy attenuation is relatively fast, and the service l...

AI Technical Summary

Problems solved by technology

However, it also faces some development difficulties, such as insufficient safety, many fire accidents, cruising range needs to be improved, battery pack energy attenuation is relatively fast, and the service life is relatively short. From the perspective of battery pack technology, the reasons for this situation Have:

[0003] 1. In the currently commonly used battery packs, if there is no liquid-cooled or air-cooled temperature control system, the battery temperature is difficult to control during the working process of the battery pack, and the safety is insufficient;

[0004] 2. If the traditional air-cooled or liquid-cooled temperature control system technology is used, the temperature distribution in the battery pack will often be uneven, and the temperature difference between the battery cells will be too large, which will affect the discharge depth and life of the battery pack.

If liquid cooling is used for cooling, the liquid cooling tube or liquid cooling plate often contains metal materials, which are easy to conduct electricity, and the insulation protection requirements for it are high, and the pipe is broken, and the risk of coolant spillage or outflow will affect the safety of the battery pack.

[0005] 3. In the traditional air-cooled battery pack for power vehicles, due to the different specific design methods, the surface uniformity of the battery cells is different. For most of this type of battery pack, the gas will be very concentrated on the surface of some battery cells. The surface area of ​​the battery cells with a wind speed above 0.01 m / s only accounts for 20% to 60% of the total surface area of ​​all battery cells, and even about 5% of the battery cells have a wind speed of no more than 0.01 m / s at any position on the surface; Currently, only 8% to 45% of the battery packs used in mainstream liquid cooling solutions are in direct contact with the liquid cooling system, and the battery cells that are not in contact with the liquid cooling system are mainly heated or heated through the internal conduction of the battery cells. cooling, the effect needs to be improved

[0006] Therefore, it is necessary to solve the problem that the temperature of the electric vehicle battery pack is difficult to control and the temperature difference of the battery cells in the battery pack is too large

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