In addition to the battery, what other factors affect the safety of electric vehicles?

Some people say that the probability of a pure electric vehicle burning in a serious collision is many times higher than that of a gasoline vehicle. Some authorities have said that the risk of electric vehicle fire is not higher than that of a conventional gasoline vehicle. So what is the safety of electric vehicles? What are the factors that affect security? What else should you pay attention to besides burning?

The driving energy of a pure electric vehicle comes from the battery in the car. Generally, the battery pack is used, that is, several small batteries are connected in series. The risk group believes that the battery pack is one of the risk factors for electric vehicles, and a short battery can cause catastrophic consequences. Of course, the battery pack must have a protection circuit, but the protection circuit may also be damaged during the impact. In the event of a short circuit, the entire battery pack is basically free of flammable materials, and the steel will burn red like a noodle. If an electric vehicle uses a hub motor, the risk of collision and resulting short circuit will increase.

The author believes that some authoritative organizations have concluded that the risk of fire in electric vehicles is not high, stemming from statistics and crash tests. In today's electric vehicles, the battery will be well protected in all directions. The crash test should be well described in this respect. However, the burning of Volanda in a certain period of time after the collision may still make the average consumer nervous. . However, there is no sufficient evidence to say that electric vehicles are not safe now. It is also a violent collision, and there is a danger of burning and explosion in the gasoline car.

It can be said that in the case of severe collision, no car is safe. In addition to burning, there may be cases where tumbling, deformation, etc. are harmful to the occupant. Electric vehicle bodies are generally heavier, and relatively light vehicles in the process of collision are still cheap, but this is not advocated by harmonious transportation. The cause of the short circuit caused by the collision of the electric vehicle is that the positive and negative materials of the battery break through the diaphragm and the ultra-high current instantaneously when the energy is quickly recharged to the battery during braking.

In any case, vehicle combustion is the most popular aspect of electric vehicle safety. Based on the existing cases, we found that there are three main situations in which electric vehicles burn: collision, charging and nature. They are formed for different reasons. For example, collision combustion is mainly caused by a short circuit in the vehicle, and combustion during charging is more due to irregular operation. The situation of spontaneous combustion is relatively diverse, and there are cases of short-circuiting by water, loose joints, and high ambient temperature.

The core of electric vehicle combustion is the battery. At present, electric vehicles generally use lithium batteries. According to reports, lithium is the most active metal in the world, and the lithium battery itself has the characteristics of small volume and high density. However, at the same time, the chemical characteristics of the lithium battery are too active, and the lithium metal is extremely susceptible to intense oxidation reaction with oxygen in the air, thereby generating combustion and explosion.

Commonly used today are ternary lithium batteries and lithium iron phosphate batteries, each of which has different characteristics. The ternary lithium battery has higher energy density, smaller size and lighter weight, but safety is often suspected. lithium iron phosphate batteries are considered to be safer despite their low energy density.

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