Will 18650 Batteries Explode When Exposed to Sunlight in a Car?

[SanTalia]

18650 batteries have the risk of explosion when exposed to sunlight in a car. Here are the relevant details: 1. Overview: Batteries placed inside a car or in high-temperature conditions may explode. If the battery is sealed too tightly, the liquid inside can expand. Sometimes, slow charging is required to prevent the sulfuric acid liquid from expanding and exploding under high temperatures. 2. Precautions: For transported batteries, proper padding and anti-collision measures should be taken to avoid severe impacts or vibrations. After outdoor high-temperature discharge or retrieval from high-temperature environments, do not charge the battery immediately. Wait until the surface temperature cools down before charging. During flight, closely monitor the battery level. If abnormal conditions such as rapid power loss occur, return or land promptly. For storage, keep the battery in a dry and safe indoor environment.

[Anthony]

To be honest, I've been driving since I was young up to my current age, and don't underestimate that big sun in the car! The 18650 battery is a cylindrical lithium-ion battery commonly used in power tools or older laptops, but it's most afraid of high temperatures. When parked in summer, the temperature inside the car can soar to over 50 degrees Celsius. After a few hours of exposure, the chemical substances inside the battery can become unstable, causing gas buildup or even thermal runaway. In mild cases, it may swell and leak, while in severe cases, it can explode or catch fire. This isn't just scare tactics—there have been similar reports in the news, like someone forgetting a power bank with 18650 batteries in their car, leading to spontaneous combustion that burned the interior. For safety, never leave such battery-powered devices exposed under the front windshield. Either carry them with you or park in a shaded area. Actually, it's not just batteries—any electronic gadget could pose this risk. Developing good habits is the best way to prevent accidents.

[Ana]

As a guy who frequently works on cars, I've seen plenty of cases where devices got damaged by sun exposure. The 18650 battery is a lithium-ion type, and high temperatures accelerate internal electrolyte reactions, leading to excessive swelling or even rupture. In-car temperatures can easily exceed 50°C under direct sunlight, causing these batteries to fail and emit smoke—in extreme cases, they might even explode. I recommend avoiding direct sunlight exposure when parked; storing them in the trunk or under the seat is a safer option. Regularly check the battery's condition too—older or damaged batteries pose higher risks. This reminds me of similar hazards like smartphones and power banks. During summer, I always remind my friends to carry their devices with them and not assume "just a few minutes" won’t matter—temperatures spike fast. Maintaining these small habits ensures worry-free driving safety.

[Lawson]

From the perspective of electronic devices, the 18650 battery is a representative of lithium cells, which are prone to issues when overheated. When temperatures in the car soar, it can damage the battery structure, increasing internal pressure and leading to leakage or rupture. The risk is even higher when parked under direct sunlight, so it's advisable not to leave it exposed. A simple protective measure is to move it to a shaded area.

[AmeliaLee]

I usually pay attention to family safety, and leaving a 18650 battery in the car is too risky. It is essentially a lithium battery, and if the chemical reaction gets out of control under high temperatures, it may explode. In summer, don't leave it in the sun when parking; it's safer to put it in the trunk or take it with you. Similarly, pay attention to batteries in children's toys—don't risk big losses for small gains. Develop the habit of checking the placement of devices, safety first.