Is It Harmful for Lead-Acid Batteries to Get Wet in the Rain?
3 Answers
Lead-acid batteries can be damaged if exposed to rain. Here is some relevant information about power batteries: High-temperature resistance: Ordinary lithium batteries are tested at high temperatures such as 200 degrees, 500 degrees, and 800 degrees, but in daily life, such extreme temperatures are rarely encountered. Precautions: Under high-temperature conditions, significant heat fluctuations can occur internally, leading to safety hazards such as explosions. The temperature limit set for lithium batteries is generally between 40-60 degrees, and they are usually labeled with explosion-proof valves. High-temperature-resistant lithium batteries can withstand up to 800 degrees.
As a mechanic with ten years of experience, I often get asked about battery issues in rainy weather. Lead-acid battery casings are sealed, so getting wet briefly in the rain isn't a big deal. However, there are two things you need to pay attention to: First, after getting wet, make sure to dry the gaps in the battery case and the electrodes, as rainwater contains impurities that can conduct electricity and slowly corrode the terminals. Second, don't charge the battery if there's water pooling in the charging port, as it may cause a short circuit and trip the breaker. The most dangerous scenario is when the casing already has cracks or has been submerged in water for half a day, as water infiltration can dilute the electrolyte and affect performance. I once repaired an elderly mobility scooter whose battery case had clogged drainage holes and was exposed to rain for three consecutive days—when opened, it was full of green corrosion. So, after getting wet, monitor it for a few days; if you notice unstable voltage during startup or unusual odors, get it checked immediately.
Last week, I forgot to cover my electric scooter parked downstairs with a raincoat, and the battery got completely soaked, worrying me all night. Research shows that basic splash-proof design is standard for ordinary lead-acid batteries, but it depends on the duration of rain and water flow direction. Rain hitting upward-facing electrodes poses higher risks, while side-placed batteries fare much better. The key is checking for water accumulation on the terminals—I wiped mine dry three times before feeling at ease. An engineer friend mentioned that aged battery case sealing rings are the real hidden danger, as new batteries can generally handle rain exposure. Instead, one should be cautious about high-pressure car wash jets directly hitting the undercarriage battery! After routine rain exposure, simply drying and ventilating is sufficient; avoid hastily using hair dryers as they may damage the casing.
