Electric bikes always cause fires, so should they be banned? Professionals respond...

“Electric bicycles are causing a lot of fires, should they be banned?”

Lithium batteries in electric bicycles and cars often catch fire during charging, use or storage, so they are very unsafe and should not be widely used.

Rumor Analysis

This statement is debatable.

Although there have been a number of reports of electric bicycle fire accidents, the real danger lies in electric bicycles and lithium batteries that do not meet safety standards.

Data shows that in 2022, a total of 18,000 electric bicycle fires were reported nationwide, up 23.4% from 2021; in 2023, the number rose to 21,000, up 17.4% from 2022. This is consistent with our usual impression - we can see news about electric bicycles catching fire every other day.

A recent electric bicycle fire accident from Shanghai Fire Department

Because of this, people have mixed feelings about electric bicycles. They are indeed convenient to ride, but the fire hazard cannot be ignored. Some people who pay special attention to safety even propose to ban or restrict electric bicycles, or replace the lithium batteries on vehicles with safer batteries. Is this view reasonable? Let's talk about it next.

In fact, China has issued many national standards and relevant laws and regulations to regulate the production and use of electric vehicles, and there are many corresponding regulations in various places, such as prohibiting electric vehicles that exceed the standard from being on the road, and strictly prohibiting electric vehicles from entering households, etc. Many electric bicycles will also add sufficient safety protection measures during the design and production process, such as battery management systems, etc.

So the question is, given so many measures, why are electric bicycle fire accidents still common in recent years, and even showing an upward trend? The main reasons may be the following.

Old electric bicycles have many hidden dangers

A crucial reason is that the supervision and replacement of some old national standard products on the market are still facing challenges . These old national standard electric bicycles no longer meet the new safety technical specifications, but due to cost considerations, the difficulty of supervision and enforcement, etc., they are still widely used. This not only poses a threat to the safety of users, but also brings hidden dangers to traffic safety.

Copyright images in the gallery. Reprinting and using them may lead to copyright disputes.

The reasons why old national standard electric bicycles continue to be used in the market include:

1. Many users are reluctant to replace their electric bicycles with those that meet the new national standards due to economic considerations;

2. Comprehensive supervision of electric bicycles that do not meet the standards is still difficult to implement, resulting in these electric bicycles still being sold and used on the market;

3. Some consumers do not understand the safety standards and specifications for electric bicycles, and therefore cannot fully appreciate the risks of using substandard electric bicycles;

4. There is a lack of effective policies and incentives to encourage users to replace old national standard electric bicycles, or to properly recycle and dispose of non-compliant electric bicycles.

To address the safety challenges of electric bicycles, incentives should be provided to encourage people to upgrade to electric bicycles that meet the new national standards, and an effective recycling system for old vehicles should be established to gradually eliminate non-compliant vehicles. At the same time, as consumers, we should consciously choose and use electric bicycles that meet the standards, jointly promote the standardization and safety of the electric bicycle market, and ensure the safety of individuals and others.

Illegal modification has many hidden dangers

Another reason for the frequent occurrence of electric bicycle safety accidents is the modification and illegal assembly of electric bicycles. In order to improve performance or save costs, some consumers choose to modify electric bicycles themselves or purchase illegally assembled batteries and accessories. These modified and illegally assembled electric bicycles have not undergone proper safety testing, and the parts used may not meet safety standards, greatly increasing safety risks.

The first problem to be addressed is overcharging and over-discharging : Informally modified batteries usually lack proper protection mechanisms to prevent overcharging and over-discharging, which can damage the chemical stability of the battery, leading to reduced battery performance and even possible explosion or fire.

Furthermore, battery mismatch is also common: during the modification process, consumers usually combine battery cells of different brands or models, which may not match in terms of capacitance, internal resistance, etc. This mismatch will make the battery more prone to overheating and increase safety risks.

Improper thermal management is another common hidden danger: Formal battery design will take thermal management into account to ensure that the battery can effectively dissipate heat under high load or special circumstances. Informally modified batteries may ignore these designs, causing the battery to overheat during use, increasing the risk of accidents.

In addition, physical damage and poor sealing are also common problems of informally modified batteries: the modification process may destroy the initial physical structure of the battery, and non-professional modifications often lack professional packaging and testing equipment, resulting in battery shell damage and poor sealing, exposing the battery to the external environment without protection, increasing the risk of leakage and damage.

Finally, insufficient circuit protection is also a problem: professional battery designs include complex circuit protection systems to prevent short circuits, overcurrent, etc. However, informally modified batteries often ignore the importance of these protection systems, making it impossible for the battery to safely disconnect power under abnormal conditions, thereby increasing the risk of safety accidents.

In view of these potential risks, unauthorized modified batteries may cause serious safety accidents, including fire and explosion, posing a threat to personal safety and property. Therefore, consumers are strongly advised to purchase and use batteries through formal channels and not to illegally modify electric bicycles to ensure the safety and reliability of batteries. It should be noted that there are clear regulations on the modification of electric bicycles. Once a fire accident occurs and it is found to be caused by unauthorized modification, it is likely that legal liability will be borne.

Are lithium batteries really that dangerous?

Can it be replaced?

The frequent occurrence of electric bicycle safety accidents, especially those related to batteries, has attracted widespread attention from the society. This makes people wonder: given the safety risks of lithium batteries, are there other energy solutions to solve these problems?

The answer is: in the foreseeable future, despite the safety challenges faced by lithium batteries, they are still the best energy solution for electric bicycles! This is mainly due to a series of significant advantages that lithium batteries have over other battery technologies:

1. One of the biggest advantages of lithium batteries is their high energy density, that is, they can store more energy in a relatively small volume or weight. This feature makes lithium batteries particularly suitable for applications that require lightweight and compact power sources, ensuring that electric bicycles can travel farther on a single charge, meeting users' daily travel needs.

2. Lithium batteries generally offer a long cycle life , meaning they can withstand thousands of charge and discharge cycles without significant performance degradation. This durability makes lithium batteries more economical in long-term use, reducing the frequency and associated costs of battery replacement.

3. Compared with other types of batteries, lithium batteries have a lower self-discharge rate, which means that the battery power loss is minimal when the electric bicycle is not in use, thereby improving energy utilization efficiency.

4. Lithium batteries can maintain good performance in both high and low temperature environments, which is especially important for electric bicycles because they need to be used in various climate conditions.

5. The customizability and flexibility of lithium battery technology allows them to be adjusted to suit various types and models of e-bikes according to different designs and power requirements.

Copyright images in the gallery. Reprinting and using them may lead to copyright disputes.

In general, in order to deal with the frequent occurrence of electric bicycle safety accidents, we need to take multiple measures. First, manufacturers should improve product safety through technological innovation, including optimizing the battery management system (BMS), developing a more stable battery chemical system, and strengthening the battery structure design, so as to improve the overall safety of electric bicycles.

Secondly, by implementing strict safety standards and regulatory measures, ensure that all electric bicycles sold on the market meet the highest safety standards. At the same time, the public should also enhance safety awareness, actively replace old national standard electric bicycles with new ones, and comply with safety regulations, such as not modifying electric bicycles privately, not charging in non-specified areas, or bringing batteries indoors for charging.

Through these joint efforts, we look forward to establishing a safer environment for electric bicycle use and more effectively protecting public safety.

Looking in the mirror of rumors

In life, there are always many risks that make people worry, but on the other hand, we must also understand that although risks are difficult to avoid completely, many risks can be evaluated and can be reduced through various safety measures. For electric bicycles, reducing risks through safety measures is more constructive than prohibiting them.

Planning and production

Author: Zhang Yan, PhD candidate jointly trained by Institute of Process Engineering, Chinese Academy of Sciences and University of Surrey, UK

Audit丨Shao Hanqi Engineer of Zhejiang Zhongke Lide New Materials Co., Ltd.

Planning丨Ding Zong

Editor: Ding Zong

Proofread by Xu Lailinlin

The cover image and the images in this article are from the copyright library

Reprinting may lead to copyright disputes