Does the electric car battery have radiation?

In 2015, China became the world's largest country in terms of electric vehicle sales, and people's concern for the safety of electric vehicles increased. From time to time, the electric vehicles that reported in the newspapers were on fire, and the radiation problems that individuals worried about came one after another, which bothered the company and confused consumers.

Is the electric car safe, or is it safe, is the battery safe? Like the fuel tanks and oils of gasoline vehicles, its safety also requires rigorous testing and inspection. The reporter interviewed some companies and researchers.

As for whether the batteries currently used in electric vehicles have radiation problems, Chuanfu Wang, president of China BYD Co., Ltd. said: "This worry is superfluous. Our products are in line with national regulations... Frankly, our bus voltage is 750 volts. In fact, like our Beijing and Shanghai friends take the subway, the voltage of the subway is 1500 volts, almost doubled, and the subway is not worried about electromagnetic interference, so don't worry about sitting on our bus. So please rest assured, take the electric bus. It is safe."

Hong Li, chief scientist of the "Long Life Power lithium battery" project of the Chinese Academy of Sciences, believes that there is no objective basis for the rumors of electric vehicle radiation and it needs to be investigated.

He said that the battery is powered by DC. In theory, electromagnetic radiation will of course be generated. However, according to relevant standards and regulations, the outside of the battery is covered with materials for shielding radiation. There should be no radiation leakage from the technical level. However, if the car fails, for example, the relevant part has a collision, although it does not affect the operation, but there is a leak in the electromagnetic shielding, which is also a problem. For the solution, "to the 4S shop to maintain the vehicle by the way to check the electromagnetic shielding situation, it is not difficult, even unreliable consumers can use a handheld instrument to detect."

For the safety limits of electromagnetic radiation, the World Health Organization's standard is less than 100μT (micro Tesla) based on magnetic induction, and China has adopted this standard. Some countries have to be wider, such as the UK is 200μT.

The safety of an electric vehicle battery refers not only to electromagnetic radiation. At present, China has 20 test items for the safety of power batteries, and all of them can pass the road. The most worrying about related companies is the battery's thermal runaway, pressure relief, fire, and explosion. In the system design, multiple security guarantees should be set by means of battery management system, fuse protection, and structural integration. In the process of matching the battery to the vehicle, it must be fully tested for durability.

However, in practical applications, there are occasions when electric vehicles are on fire. For example, in December 2015, an electric bus in Hong Kong suddenly caught fire, which may be caused by a short circuit. The "star" Tesla in the electric car is expensive and claims to be safe, but in January this year there was a charging fire in Norway.

Government departments have always attached great importance to the safety of electric vehicles. China's Ministry of Industry and Information Technology announced in January that for safety reasons, the suspension of the ternary lithium battery bus was included in the list of recommended models for the promotion and application of new energy vehicles. The Ministry of Industry and Information Technology said that the ternary lithium battery has high energy and good cycle performance, which is an important development direction for lithium batteries in the future. However, in this field, China started late, and the safety development and verification for passenger cars is not enough. More needs to be done security assessment. Before the evaluation is completed, the ternary lithium battery bus will be suspended for inclusion in the recommended model list.

Nowadays, mainstream lithium-ion batteries can be divided into various types such as lithium iron phosphate, ternary lithium, lithium manganate, and lithium nickelate due to different materials. Researchers are developing new solid-state lithium batteries. It replaces the electrolyte from a liquid to a solid, which greatly improves safety. For example, the Autolib electric car introduced in Paris, France uses a solid-state lithium battery. In a riot, one car was burned out, but after the burn, the battery was still there. Li Wei said that this case shows that the new battery has better safety.

Today, with the increasing number of electric vehicles, the absolute number of electric vehicle-related accidents may gradually increase. However, there are some accidents like traditional gasoline vehicles. Paying attention to the safety of electric vehicles should be considered from the perspective of probability. Simply saying that "battery is fierce" is a great misunderstanding.

The page contains the contents of the machine translation.