Why Do E-Scooter Fires Happen? How 21700 Battery Safety Standards Prevent Explosions

Nowadays, electric scooters can be seen everywhere around us, zipping through the streets of the city. But recently, a question has been lingering in the minds of many people: battery fires. Let's take a deep dive to find out what exactly is going on with the lithium-ion batteries that power our beloved electric scooters.

Common Causes of Lithium-ion Battery Fires in Electric Scooters

Lithium-ion batteries are the power source for millions of electric scooters worldwide. They store a large amount of energy, which is great, but this high energy density also comes with some potential risks. One of the most terrifying situations is thermal runaway. It's like a domino effect of overheating that can lead to a fire. Usually, it starts with an internal short circuit. And there are various reasons for this short circuit. Maybe the battery has suffered physical damage, such as when the electric scooter takes a hard fall. Sometimes, it's due to manufacturing defects because not all batteries are perfectly made. Also, our own charging habits play an important role. If we overcharge the battery, making it exceed its voltage limit, it will put a great deal of stress on the small electrochemical cells inside. In addition, if the battery is exposed to extreme temperatures, whether it's extremely hot or cold, it will accelerate its aging process. Even a tiny puncture on the battery casing can be a big problem. That small hole can damage the separator between the anode and the cathode, creating conditions that are prone to sparking.

The Role of 21700 Battery Design in Fire Prevention

Fortunately, modern technology has stepped in to help. The 21700 battery cells are playing their part. They have come up with three very clever innovations to address the safety issues we just mentioned. First, take a look at their size and shape. They are larger and cylindrical, with a diameter of 21 mm and a height of 70 mm. Compared with the old 18650 model, this makes them more structurally stable. It's like building a sturdier house for the battery components. Second, they have improved the cathode. Using an advanced nickel-cobalt-aluminum (NCA) cathode means that the battery can better cope with heat. It can even resist decomposition at temperatures as high as 150°C. This is a huge improvement. Then there's the smart Battery Management System (BMS). These are like the little guardians of the battery. They continuously monitor the voltage of each individual battery cell in real-time. So, if the voltage suddenly spikes or the battery starts to overheat, the BMS will automatically cut off the power supply. All these upgrades combined have successfully reduced the failure rate by up to 40% compared to the batteries we used in the past.

Practical Steps to Reduce the Risk of E-Scooter Fires

As electric scooter users, we also play an important role in preventing these battery fires. There are three simple things we can do. First, always use the charger recommended by the manufacturer and make sure it matches the input specifications of the battery. You might be tempted to use a universal charger, but those chargers often can't regulate the voltage properly. It's like trying to unlock a door with the wrong key. It won't work and may even cause problems. Second, the place where we store our electric scooters matters. Store them in a dry place and make sure the temperature is controlled, preferably below 25°C. This helps prevent the electrolyte inside the battery from leaking. Finally, there's a very practical 80-20 charging rule. Don't let the battery run down below 20%, and stop charging when it reaches 80%. This helps reduce the stress on the battery cells. If you don't plan to use the electric scooter for a while, such as for long-term storage, make sure the battery charge is maintained at 50% and store it in a fireproof container. Many ordinary riders like us often overlook this important step, but it really can make a big difference.

How Safety Certifications Ensure Battery Reliability

When we go to buy an electric scooter, how do we know if the battery is safe? That's where international certifications like UL 2271 and UN 38.3 come into play. These certifications have very strict testing procedures for lithium-ion batteries. For example, they subject the battery to a 360-hour temperature cycle, ranging from extremely cold -40°C all the way to hot +70°C. They also conduct a 48-hour altitude simulation to see how the battery performs under different conditions. Then there's the nail penetration test, just as its name suggests. They want to see if the battery can resist explosion under these extreme tests. Certified batteries must also be able to withstand 150% of the rated voltage without releasing any dangerous gases. Manufacturers that obtain these certifications must prove that their batteries can withstand a great deal of stress. They need to meet a compressive threshold of over 13 kilonewtons, which is approximately equivalent to the weight of a mid-sized car. This means that even if the electric scooter crashes, the battery should still maintain its structural integrity.

Future Innovations in Battery Safety Technology

The future looks promising when it comes to the safety of electric scooter batteries. There are some amazing emerging technologies on the horizon. For example, solid-state electrolytes are being developed. This is great because they eliminate the flammable liquid components in the battery. Experts believe this has the potential to reduce the fire risk by a significant 90%. There are also graphene-reinforced separators. They are so sensitive that they can detect internal pressure changes 300% faster than the materials we use now. This means that if something goes wrong, they can shut down the battery earlier. Some prototypes even use fire extinguishing gels. These gels activate at 100°C and cover the damaged battery cells with a fire-retardant compound. And that's not all. AI-driven charging algorithms are also being developed. These algorithms can be adjusted according to the way we use our electric scooters. With all these advancements, the goal is to almost eliminate catastrophic battery failures by 2030.