Bainistíocht theirmeach feithicle leictreach
Battery pack is the main energy storage component of electric vehicle. It is composed of lithium battery, which directly affects the performance of electric vehicle. Due to the limited space for loading batteries on the vehicle, the number of batteries required for normal operation is also large. The batteries will discharge at different rates and generate a large amount of heat at different heat generation rates. In addition, time accumulation and space influence will accumulate a large amount of heat, resulting in complex and changeable operating ambient temperature of the battery pack.
The temperature rise in the battery pack seriously affects the operation, cycle life, charging acceptability, battery pack power and energy, safety and reliability of the electrochemical system of the battery pack. If the electric vehicle battery pack cannot dissipate heat in time, the temperature of the battery pack system will be too high or unevenly distributed. As a result, the battery charge discharge cycle efficiency will be reduced, the power and energy of the battery will be affected, and in serious cases, the heat will be out of control, affecting the safety and reliability of the system.
Therefore, in order to improve the vehicle performance and give full play to the best performance and service life of the battery pack, it is necessary to optimize the structure of the battery pack and design a battery pack thermal management system that can adapt to high and low temperature.
Córas fuaraithe aeir:
The air cooling method is the most simplest way. It only needs to let the air flow through the battery surface to take away the heat generated by the power battery, so as to achieve the purpose of heat dissipation of the power battery pack. According to different ventilation measures, air cooling has two ways: natural convection heat dissipation and forced ventilation heat dissipation.
Natural convection heat dissipation does not rely on external additional forced ventilation measures (such as adding fans), but is cooled and dissipated by the air flow generated by the temperature change of the fluid in the battery pack. Forced convection cooling and heat dissipation system is a heat dissipation system based on natural convection heat dissipation system and corresponding forced ventilation technology. At present, there are two kinds of air-cooled cooling systems for power batteries: series system and parallel system. However, the effect of this method is poor, and it is difficult to achieve high battery temperature uniformity.
Córas fuaraithe leachtach:
The liquid cooling heat dissipation system of power battery refers to thermal system in which the refrigerant directly or indirectly contacts the power battery, and then takes away the heat generated in the battery pack through the circulating flow of liquid fluid to achieve the heat dissipation effect. The refrigerants can be water, a mixture of water and ethylene glycol, mineral oil and R134a. These refrigerants have high thermal conductivity and can achieve good heat dissipation effect. At present, the liquid cooling technology of power battery also has quite mature technology, and has been widely used in the heat dissipation system of electric vehicle.
Fuarú Píopa Teasa:
As an efficient heat conduction element, heat pipe can quickly and efficiently transfer heat from one place to another, it can quickly and effectively transfer heat between two objects. In the thermal management system of electric vehicles, many scholars at home and abroad also apply the heat pipe, a heat conduction element, to the heat dissipation of power batteries. Compared with the traditional forced convection heat dissipation system, in the heat dissipation system with heat pipe, the power battery can not only maintain the normal working temperature range, but also maintain the temperature uniformity among the battery cells, which is an effect that the forced cooling heat dissipation system can not achieve. However, its mass and volume are too large, and there is a heat transfer limit.
