Electric Bike Batteries: A Hidden Danger?

Electric bikes, or e-bikes, are a trendy and convenient mode of transportation. However, their batteries, typically lithium-ion, have raised safety concerns due to a rise in fires and explosions. While e-bike batteries are generally safe, improper use, charging, and storage can lead to overheating, chemical reactions, and fires. The popularity of e-bikes has resulted in an increased focus on battery safety, with incidents causing injuries and even deaths. To mitigate these risks, it is crucial to follow manufacturer instructions, use recommended chargers, and avoid leaving batteries unattended during charging.

Lithium-ion batteries can store a lot of energy in a small space, causing overheating and fires

Electric bikes, or e-bikes, are powered by lithium-ion batteries. These batteries are also commonly found in cell phones, laptops, electric toothbrushes, power tools, and electric vehicles. Lithium-ion batteries are popular because they are rechargeable, long-lasting, and can store a lot of energy in a small space. However, this high energy density also poses a safety risk, as the batteries can overheat and cause fires or explosions if not properly cared for.

The potential for lithium-ion batteries to overheat and cause fires is due to their ability to store a large amount of energy in a small space. When a lithium-ion battery fails or overheats, it can violently eject gas, projectiles, and flames, which can then spread to other cells in a chain reaction. This is known as "thermal runaway" and can be triggered by internal failures, such as a short circuit, or external damage.

The risk of fire or explosion associated with lithium-ion batteries has led to safety concerns, particularly in light of several recent incidents. In April 2022, a spate of fires caused by lithium-ion batteries in New York City and Florida prompted fire departments to issue warnings and safety tips for the care and keeping of these batteries. In one incident, a Florida bike shop burned down after a refurbished e-bike battery was left on the charger overnight. In another incident in November 2022, a fire caused by a lithium-ion battery in an apartment building in Manhattan injured nearly 40 people.

To minimize the risk of fires associated with lithium-ion batteries, it is important to follow the manufacturer's instructions for charging and storage. It is recommended to only use the charger provided by the manufacturer and to avoid leaving the battery charging unattended or overnight. Additionally, it is important to store lithium-ion batteries at room temperature in a dry, moisture-free environment and to keep them away from direct sunlight or hot vehicles.

While lithium-ion batteries have the potential to cause fires, it is important to note that they are generally safe when used and stored properly. Reputable brands of e-bike batteries are designed with safety features, such as a battery management system (BMS), to regulate the performance of each battery cell and prevent overheating.

E-bike batteries should never be left charging overnight or without supervision

Electric bike batteries, which are lithium-ion batteries, are a popular power source in electronic devices and vehicles due to their ability to store a large amount of energy in a small space. However, they can pose a serious fire risk if not handled properly. For this reason, it is important to never leave e-bike batteries charging overnight or without supervision.

Lithium-ion batteries can store a large amount of energy, and improper care and keeping of these batteries can result in fires. In the case of a failing battery, it can violently eject gas, projectiles, and flames, which can then spread to other cells in a chain reaction. This has been the cause of several fires in New York City, with six people dying and 139 injured as a result of battery-caused fires in 2022.

To prevent such incidents, it is crucial to follow the manufacturer's instructions for charging and storage. Always use the manufacturer's cord and power adapter made for the device, and avoid aftermarket, off-brand, or bargain batteries. Additionally, do not leave a charging e-bike battery unattended or on the charger overnight. If you're charging your e-bike in a garage, set a timer to remind yourself to unplug it when it's done, and unplug it if you need to leave the house.

While newer electric bike batteries are designed to manage many hours of electric charging and prevent overcharging, it is still important to take precautions. If the battery is not charged correctly or has been previously damaged, overnight charging or any lengthy charging could be harmful. It is recommended to keep your battery charged at around 80-90% for longer life, and to store it at room temperature in a moisture-free environment.

Only use batteries and chargers that originally came with the e-bike

Electric bike batteries are generally safe and can be used with little risk. However, there have been several incidents of fires and explosions related to e-bike batteries in recent years. These incidents have raised safety concerns and highlighted the importance of taking precautions when using and charging e-bike batteries.

To ensure the safe use and charging of your e-bike battery, it is important to only use the battery and charger that originally came with your e-bike. Using aftermarket, off-brand, or bargain batteries and chargers can increase the risk of fire and other hazards. Original batteries and chargers are designed specifically for your e-bike model and have undergone rigorous testing to ensure compatibility and safety. They are also manufactured with high-quality components that reduce the likelihood of malfunction and failure.

By using the original battery and charger, you can be confident that they meet the required safety standards and have passed industry regulations. Reputable e-bike brands, such as Liv Cycling, invest in research and development to create safe and reliable batteries. They collaborate with leading battery manufacturers, like Panasonic, to design, assemble, and test their batteries, ensuring the highest safety standards.

Additionally, the original battery and charger are designed to work optimally with your e-bike. The battery management system (BMS) in the battery communicates with the smart charger to ensure that individual cells are charged at the optimum rate. This helps prevent overheating and maintains the long-term performance of your e-bike battery. Using a different charger may compromise this communication and increase the risk of overcharging, which can lead to safety hazards.

It is also important to follow the manufacturer's instructions and recommendations for charging and storage. This includes charging your e-bike in a well-ventilated area, avoiding extreme temperatures, and never leaving the battery unattended while charging. By adhering to these guidelines, you can significantly reduce the risk of accidents and ensure the safe use of your e-bike.

Avoid aftermarket, off-brand, or bargain batteries

Electric bike batteries are generally safe and can be used with little risk. However, there have been several incidents of fires and explosions related to e-bike batteries, prompting safety concerns. To minimize the risks associated with e-bike batteries, it is crucial to avoid aftermarket, off-brand, or bargain batteries. Here's why:

First, cheaper batteries are more likely to be cheaply made, and old batteries are more susceptible to malfunctioning. The risk of overheating increases when batteries are cheaply made, old, or both, making them more prone to malfunction. A malfunctioning battery can violently eject gas, projectiles, and flames, which can have disastrous consequences.

Second, some manufacturers of budget e-bikes cut corners to lower manufacturing costs. This can include reusing parts of used battery packs from electric cars, which Jack Hao of battery manufacturer Phylion warns can increase the likelihood of a fire hazard.

Third, the weak regulatory environment in the United States has left consumers with poor options, according to Percy Chien, executive chairman of the Taiwan-based Fairly Bike Manufacturing Company.

Finally, the economics of budget e-bikes raise questions about the quality of their batteries. Mike Fritz, a chief technology officer at a micromobility industry consulting firm, notes that a high-quality e-bike battery alone costs around $750. A complete e-bike that costs less than this raises doubts about the quality of its battery and other components.

Therefore, to ensure safety and reduce the risk of fires and explosions, it is essential to invest in a high-quality e-bike and battery from a reputable brand. While it may be more costly upfront, it will provide peace of mind and help avoid potential safety hazards associated with lower-quality batteries.

Store batteries at room temperature in a moisture-free environment

Electric bike batteries, specifically lithium-ion batteries, can be dangerous when used or stored incorrectly. They can store a large amount of energy, and improper care can result in fires. In fact, lithium-ion batteries have been the cause of several fires and even deaths in New York City.

To prevent this, it is important to store batteries at room temperature in a moisture-free environment. This is because lithium-ion batteries have a recommended temperature range for storage. Storing them in a cold place, like a garage, can slow down chemical reactions, but it can also be detrimental. For example, lithium-ion batteries have lower capacity at lower temperatures, and at -30°C, most cells are practically useless. On the other hand, storing batteries in a hot environment can cause them to discharge quickly. Therefore, it is best to store them at room temperature, ideally between 15-20°C, to ensure optimal performance and safety.

Additionally, storing lithium-ion batteries in a humid environment can cause them to spoil. This is because condensation can build up between the terminals, causing a short circuit. In extreme cases, this could even lead to a fire. As a result, it is crucial to store batteries in a dry, moisture-free environment to prevent any potential safety hazards.

To summarise, by storing electric bike batteries at room temperature in a dry, moisture-free environment, you can maintain their performance and significantly reduce the risk of any fire-related incidents.

Frequently asked questions