电动车为什么不能进电梯？

English (for the teacher)

At nine in the evening, a resident wheels an e-bike into the lift of his housing compound, meaning to take it home to charge. But the lift doors refuse to close, and the speaker overhead tells him again and again to push the e-bike back out. Today, in many Chinese cities, this scene has become common. Once the camera in the lift recognises an e-bike, the doors will not close until the bike has been pushed out.

Q: How common are e-bikes in China?

A: E-bikes are cheap, take little effort to ride and need no driving licence, so they are the main way many people get to work, take children to and from school and deliver takeaways, and there are now more than 300 million of them across the country. Precisely because so many people use them, charging has become a big problem: many people living in tall apartment blocks have no garage downstairs and nowhere to charge, so some park their bikes in the stairwell and others simply wheel them into the lift and take them home.

Q: So what exactly is the danger of an e-bike in a lift?

A: The key is the battery. When an e-bike battery, especially a lithium battery, is overcharged, knocked hard or illegally modified, it can go into 'thermal runaway': its temperature shoots up in a very short time, and the battery catches fire or even explodes. Fire services point out that these fires burn fast, burn hot and give off a lot of toxic smoke. If thermal runaway happens in a closed space like a lift, the passengers have almost nowhere to escape; if it happens in a stairwell, the thick smoke can block the escape route for everyone in the building.

Q: Is this actually the law?

A: That's right. The Fire Safety Management Rules for High-Rise Civil Buildings, issued by the Ministry of Emergency Management, took effect in August 2021; they clearly ban parking or charging e-bikes in the public lobbies, corridors, stairwells and safety exits of high-rise buildings, and they encourage housing compounds to set up central areas for parking and charging. Many local e-bike regulations go further, banning e-bikes from lifts and banning 'flying-wire charging', that is, hanging a cable from an upstairs window to charge a bike below. Many cities have also fitted lifts with e-bike blocking systems, which is exactly how the scene at the start came about.

Q: Does everyone agree with it?

A: Not entirely. Supporters argue that when one e-bike catches fire, it threatens the whole building, and the lives of dozens of households cannot be put at risk. Opponents complain that their compounds have too few charging points, that they have to queue after work, and that a bike left downstairs might have its battery stolen; in their view, banning without building just pushes the problem onto residents. As the saying goes, 'better to channel than to block', and many places are now banning on one hand while speeding up the building of central charging sheds on the other, where residents scan a code to charge and pay for the time they use.

Q: What can ordinary people do?

A: Fire services keep repeating the same advice: buy bikes and batteries that meet national standards and don't modify them; use the original charger; cut the power as soon as charging is done and avoid charging overnight; and park outdoors or in a shared bike shed whenever you can. If a battery starts smoking, swelling or making strange noises, get away from it at once and call the fire emergency number, 119.

An e-bike makes life easier for one person, but what it affects is the safety of an entire building. If the only place to charge in your building were a queue downstairs, what would you choose?

Answers

1. B. 门不会关上: 电梯里的摄像头一旦识别出电动车，门就不会关上，直到车被推出去为止。
2. C. 温度会很快升高，然后起火: 温度在极短的时间内急剧升高，电池随即起火，甚至爆炸。
3. C. 他们觉得充电的地方太少: 小区里的充电桩太少，下班后要排队，车停在楼下还担心电池被偷