Battery Thermal Management Ensures Safety And Performance
Reasons to invest in battery thermal management system
The service life and safety performance of the power battery is affected by the thermal management system of the power battery. The reason is that the lithium battery generates heat during charging and discharging resulting in a rise in temperature, and many of the battery’s performance (charging efficiency, number of cycles) and parameters (internal resistance, voltage, SOC and available capacity) will change with the temperature.
When the temperature is too high, the battery capacity will decay and the risk of thermal runaway will increase, in which case heat dissipation is required; and when the temperature is too low, the battery capacity and performance will decay significantly, and when charging in this case there will also be an internal short circuit leading to the risk of thermal runaway, and heating is required.
In order to maintain temperature consistency, power batteries need to minimize temperature differences in space, in order to achieve the ideal operating temperature, engineers have adopted active and passive battery thermal management systems (BTMS) to manage the battery. So as consumers become more and more concerned about range and safety, the battery thermal management industry has become the focus of more and more manufacturers and investors.
Classification and introduction of thermal management methods
Generally speaking, there are three types of battery cooling systems, mainly divided into three major categories: air cooling, liquid cooling and direct cooling.
The air cooling system uses the natural wind or the cooling wind in the passenger compartment to take away the heat from the surface of the battery so as to dissipate the heat; the liquid cooling system uses the cooling flow channel to take away the heat through the heat exchange between the cooling liquid in the flow channel and the battery; the direct cooling system uses the refrigerant to cool the power battery directly, which eliminates the cooling pipeline of the power battery compared with the liquid cooling system.
At present, Trumonytechs mainly adopts the mode of liquid cooling for thermal management of the battery pack, and this is also the way currently adopted by head new energy vehicle manufacturers, which is the mainstream of cooling, such as Tesla and volt. the main task of heat dissipation is not to prevent overall overheating, but to prevent local overheating, so it is necessary to keep the temperature of each component consistent.
Trumonytechs uses its extensive experience in the thermal management industry to help customers achieve their cooling goals for temperature consistency issues. Taking flow channel design as an example, based on fluid mechanics, heat transfer simulation and engineering practice, engineers design flow channels reasonably inside the battery pack, and change the flow direction periodically through the coolant to achieve temperature consistency inside the battery pack.
The challenge of achieving the ideal thermal management system
There are three conditions that must be met to achieve the ideal thermal management system: dissipating heat when the temperature is too high, heating when the temperature is too low, and maintaining the consistency of the battery temperature so that the temperature is within the right range. The main challenge encountered by the heat pipe industry today is to maintain the consistency of the battery temperature.
Temperature consistency is important for the following reasons
- The performance and reliability of a battery system depends on the weakest cell, and the safety of the system depends on the least stable cell.
- Operating temperature can cause secondary inconsistencies between cells. Primary inconsistency mainly refers to the inherent differences in the cells when they leave the factory, while the differences in the individual cells that gradually increase during use are called secondary inconsistency.
- The expansion of cell differences is a gradual process, but the weakest link will suddenly trigger the thermal runaway of the battery pack but, and the cause of thermal runaway lies in the chain reaction.
The arrangement of the cells, the shape of the pack, the arrangement of the whole vehicle and the different flow conditions all bring great challenges to the thermal management of the cells. Take Tesla’s battery pack as an example, the pack is irregularly distributed, so the difficulty of subsequent thermal management design, simulation and testing is immeasurable.
Benefits of Thermal Management
Thermal management of new energy vehicles is very important as it can affect the performance and lifetime of new energy vehicles with the following benefits:
Improved energy utilization: Both the battery and the motor in a new energy vehicle need to be maintained within a certain temperature range for optimal performance. By controlling the thermal management system, the battery and motor can be kept within the appropriate temperature range, improving energy utilization and extending battery life.
Ensure driving safety: The performance and life of new energy vehicles can be affected in high or low temperature environments. If the temperature of the battery or motor is too high or too low, it may lead to vehicle performance degradation or system failure, and may even endanger driving safety. Therefore, the control of thermal management system can ensure driving safety.
Reduce energy consumption: In a low temperature environment, the electrochemical reaction of the battery slows down and the internal resistance increases, which leads to increased energy loss. And in a high temperature environment, the cycle life of the battery is also affected. Through the control of thermal management system, energy consumption can be reduced and battery life can be extended.
Improve comfort: The heat generated by the battery and motor in the new energy vehicle will affect the temperature inside the vehicle, and the control of the thermal management system can regulate the temperature inside the vehicle and improve the comfort of passengers.
In summary, new energy vehicle thermal management is very important for improving energy utilization, ensuring driving safety, reducing energy consumption, and improving comfort.
Thermal Management Industry Value
New energy vehicles have a very good development prospect. From the market side, the market competition pattern has not yet been established, the market is growing rapidly, it is a very good entry point to enter; from the policy support side, governments are actively promoting the development of new energy vehicles, the introduction of relevant policies, such as purchase tax exemptions, free licenses, etc.; then from the technological innovation level, with the development of the new energy vehicle market, the new energy vehicle thermal management technology is also constantly innovating and improving; finally, from the environmental protection and energy saving point of view, the thermal management technology can effectively control the temperature of the vehicle. New energy vehicle thermal management technology is also constantly innovating and improving; Finally, from the perspective of environmental protection and energy saving, new energy vehicle thermal management technology can effectively control the temperature of the vehicle, reduce energy consumption and emissions, so as to achieve the goal of environmental protection and energy saving.
In summary, the new energy vehicle thermal management is a field with great potential. With the gradual maturity of the new energy vehicle market and the increasing demand of users, thermal management system will become an important point of differentiation and competition. Investors can focus on related technology companies or new energy vehicle manufacturers to find investment opportunities in this field.