In the collision of a pure electric vehicle, the power lithium battery is deformed by impact and extrusion, and the battery core may be thermally out of control and catch fire; other parts inside the battery pack may also be squeezed and impacted during the collision, and a short circuit may occur. There is even a danger of fire and explosion; the high-voltage cables and high-voltage devices inside the battery pack are easily scratched or torn during a collision, and there may be a short circuit and a fire may also cause electric shock injuries.
The key to collision protection of power lithium batteries is to control the deformation of the battery pack shell structure during a collision and try to prevent internal components from being impacted and squeezed. In addition, the battery core and high-voltage components themselves should also have a certain resistance to squeezing and puncture. In recent years, some researchers are studying some buffer structures, which can absorb part of the impact energy during a collision, so as to alleviate the acceleration impact of the battery pack. This may have positive uses for the durability of the battery pack, but it does not have much significance for the collision protection of the battery pack.
To strengthen the safety of the power lithium battery and prevent the battery from deflagration due to collision, we can start from the following aspects:
1. Strengthen battery protection: New energy vehicles should use a dedicated platform as the vehicle platform to prevent continued use of the "oil-to-electricity" platform so that the position of the power lithium battery pack can be moved from the position of the trunk that is prone to impacts to the vehicle chassis. Reduce the probability of impact on the power lithium battery.
2. Pay attention to safe driving: Drivers should pay attention to safe driving when driving to prevent traffic accidents. Do not drive the car on the road easily. When the vehicle passes through the pit, it must slow down to prevent the vehicle from supporting the bottom and damaging the battery.
3. Strictly control battery quality: battery manufacturers must strictly control battery quality and strictly prohibit the introduction of under-certified batteries into the market. The battery must be subjected to safety tests such as water immersion, squeezing, collision, puncture, and burning according to the requirements of national standards, and can enter the market after passing it.
The key to collision protection of power lithium batteries is the response time of the system to a collision accident, that is, the time from the occurrence of a collision to the high-voltage power failure of the vehicle. The shorter the response time, the more beneficial the protection of users and batteries. The collision protection system requires a certain processing time, including the time for receiving and confirming the collision signal and controlling the actions of the corresponding equipment.
The above is how to prevent collisions with power lithium batteries. The higher the protection level, the higher the manufacturer's manufacturing cost, especially the liquid intrusion protection is very complicated. At present, the high-voltage parts of lithium-ion batteries are generally IP67 protection level, including some smart phones that are known to be "waterproof". This standard is also adopted.
