5 steps to solve electric vehicle safety issues

To choose the right electric car, it is very important to understand the power lithium battery. Today, the editor will teach you 5 steps to analyze the safety issues of electric vehicles. Let's follow the automotive electronics editor to learn about the relevant content.

Part 1: First look at the three-dimensional structure of electric vehicles

From this picture, we can see that the batteries are distributed on the car chassis.

Tesla electric car chassis

Second bullet: It is confirmed that the batteries are distributed on the chassis, but it is not just one battery, but many batteries connected in series. Take the cylindrical lithium battery as an example, the truth is shown in the picture above.

When batteries are connected in series, they must have extremely good consistency, that is, the capacity of each battery must be the same. Otherwise, when charging, if one battery is not fully charged and the other is overcharged, the danger will be very great.

If you use fast charging instead of slow charging at this time, such a large amount of energy will be input into the enclosed space in an instant, and the risk factor will be magnified many times.

The editor strongly recommends that electric car owners give priority to slow charging. First, it is safe, and second, it is beneficial to battery life.

Part 3: Causes of thermal runaway

As a high-energy carrier, the safety issues of power batteries come from their energy release, which includes electrical energy release and chemical energy release. The safety issues caused by chemical energy release are ultimately manifested in thermal runaway and combustion or explosion caused by the extension of thermal runaway.

Episode 4: Response from thermal abuse to thermal runaway

Part 5: 7 stages of thermal runaway (estimated to be within 2 seconds)

Thermal runaway stage, irreversible and uncontrollable

Based on the above analysis, power battery manufacturers and users bear important responsibilities to ensure the safety of electric vehicles.

1. User: Drive carefully to avoid collisions. Observe the road surface to prevent the bottom battery from being squeezed or punctured. Strictly follow the requirements when charging. Do not choose fast charging if slow charging is possible. Do not overcharge or over-discharge.

2. Power battery suppliers: Improve the consistency of battery cells; BMS can respond and control dangers in a timely manner.