Lithium batteries are widely used in renewable energy vehicles due to their high capacity, high voltage, high specific power, good cycle performance and no pollution. To meet the power requirements for normal driving, the number of batteries is large, and each cell is arranged in parallel to form a battery pack to save space. Individual temperature differences are caused by the different heat dissipation environments in the battery.
Under the influence of thermoelectric coupling, the resistance in the battery will be reduced at high temperature, causing the current that passes through the battery to increase, and the condition of the same place where the battery becomes more negative, this increases it battery damage, and affect the performance and life of the battery, and even have serious safety risks. Therefore, it is important to understand the effective temperature control for the thermal insulation performance of the battery cell and the mismatch between the cells.
Research shows that the most effective temperature range of lithium batteries is 15-35 ℃, control the temperature difference between the same cells does not exceed 5 ℃, the optimal temperature does not exceed 55 ℃, and the battery can work for life the better.
Of course, this is based on a research study, cylindrical lithium battery research, we will talk about common temperature control technologies including air cooling, water cooling, and time-varying cooling. Compared to other cooling methods, air cooling technology has a low cost and a simple process design. It has become one of the most widely used solutions for power lithium battery power management.
The thermal performance of the cooling system is greatly affected by the characteristics of the circulation and heating system. The properties of the media affect the thermal efficiency of the cell surface and the thermal heating system affects the space inside the battery of the battery, which affects the total thermal energy. Through experiments and numerical simulations, the thermal efficiency of the cooling mist is investigated, and it is found that the temperature distribution of the cell is more stable and lower by using a cooling mist system than by using a dry air system makes it cool, performance is improved by up to 45%. CFD simulations are performed on the air-cooled system to investigate the effect of cell operating parameters on the design and cooling performance.
The results show that reducing the intake air temperature or increasing the intake air temperature can reduce the maximum cell temperature. Changing the part of the inlet chamber and air intake can significantly improve the cooling performance of the system.
The optimal pressure chamber width and cell spacing parameters are determined separately using a combination of Newton’s initialization method and water resistance network simulation. A process with design optimization based on the solution principle has improved the cooling performance and reduced the maximum battery temperature difference by more than 40%.
Air cooling was also done with thermoelectric technology couples, and numerical calculations showed that the battery temperature can be kept below 35 °C with a temperature difference of less than 5 °C at low temperatures big debt and debt settlement and higher temperature above 40 °C.
Conclusion
Modeling and numerical simulation of the cold heat dissipation process of cylindrical lithium battery fork arrangement. The closer the cells are to the shell, the better the flame retardant effect of the cells. For the cells that are connected in the same line, the air current increases gradually, and the discharge effect of the single cell is worse.
