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Moisture and UPS battery backups are two things that should never go together. So, if you suspect that your battery is leaking, you must take notice and investigate further. Leaks can be dangerous for both you and anything around the UPS unit.
Firstly, an apparent leak might not be a leak at all. The moisture you find in or around your UPS unit could be from a leaking air conditioning unit nearby or the condensation of normal battery gasses that flow out from the unit. However, a damaged case and corrosion will cause the battery to leak the fluids inside.
Here, you’ll discover the critical steps to take when your UPS battery leaks. Then, you’ll learn the possible causes and how you can fix or prevent them.
Leaking UPS Battery: What To Do First?
A leaking UPS battery backup is dangerous to you physically and to any other devices nearby.
So, if you even so much as suspect that your UPS battery is leaking, here are the steps you must take immediately:
- First, disconnect any devices that you’ve plugged into the UPS.
- Then, shut off your UPS and disconnect it from the wall socket.
- Finally, ventilate the area or move the battery to a safe location outdoors.
From there, you should wear protective gear to safely remove and dispose of the leaking battery. Unfortunately, you can’t repair that leaking battery and must purchase a replacement.
Read: How To Check UPS Battery Health?
Why Is My UPS Battery Backup Leaking?
After handling your leaking UPS battery safely, it’s time to understand how the leak occurs and what you can do to deal with it in the future.
External Moisture (Not A Leak)
What it is: Let’s suppose you find moisture in or around your UPS battery backup. Although that moisture might come from a leaking battery, you must first determine whether or not it’s moisture from an external source.
Unfortunately, there’s a possibility that the battery isn’t leaking. Still, the water spilled onto the UPS casing from somewhere else, like an air conditioning unit.
How it happens: UPS units, particularly heavy-duty and industrial models, are often placed in rooms with air conditioning units. The air conditioning is a requirement to keep UPS backup batteries within safe operating temperatures.
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Sadly, those air conditioning units run the risk of leaking water onto anything that’s directly beneath them. So, if there’s an air conditioning unit or outlet directly above your UPS, check to ensure that the moisture on your UPS didn’t come from there.
How to resolve it: The first thing you must do is to get the UPS out of harm’s way. Next, move it to a part of the room where there is no possibility of water spilling onto or near the unit.
For example, no air conditioning unit, plumbing, or other water sources should be directly above the UPS.
Besides that, you should also keep the UPS away from places where people might put drinks or other fluids, such as on an office desk.
Read: How To Troubleshoot UPS Battery?
Condensation Of Battery Gasses
What it is: UPS battery backups generate gasses like oxygen and hydrogen during normal operations. These gasses are produced as byproducts when the battery charges or discharges.
On UPS batteries, these gasses remain at very low concentrations. That means the gasses aren’t harmful to anyone nearby if inhaled. Besides that, the concentration is also too low to cause an explosion.
The gasses stay at low concentrations because they can escape through vents built into the battery.
How it happens: Here’s another example of how you might find moisture coming from a UPS battery backup, though it’s not from a leak.
Remember: UPS batteries produce some gasses like hydrogen when working normally. Those gasses escape through vents built into the battery casing to ensure they don’t build up inside.
As those gasses escape, they can condense into water droplets when they come into contact with cold air. That will explain why there’s moisture seemingly leaking from your UPS battery.
How to resolve it: One way to minimize the excess condensation is to adjust the room’s temperature.
The cooling system should be set to a temperature within the manufacturer’s recommendation to keep the UPS cool, yet not too cold that it causes excess condensation.
Read: What Happens When UPS Battery Fails?
Damaged Battery Casing
What it is: A UPS backup battery consists of a sturdy plastic casing that houses the electrolyte and other crucial components.
The casing is crucial to ensure that all those components and any gasses they generate stay contained safely within the battery and do not leak out.
The casing also has built-in vents that allow those gasses to escape safely if necessary.
How it happens: Despite the durability of a UPS battery casing, it can also get cracked. That crack will cause the electrolyte within to leak out of the battery, flooding your UPS from inside.
It’s not easy to crack a UPS case, which is why it generally only happens for two reasons.
Firstly, the battery will develop cracks if it suffers a strong impact, such as during transportation.
Secondly, the casing will also crack if the battery is faulty and starts to bulge. When overlooked, a defective battery can continue to swell until the case becomes too big and cracks itself.
How to resolve it: Unfortunately, the UPS battery’s casing is not repairable or serviceable. Patching up any cracks you find is also not a good idea, so it’s best to avoid trying that.
Instead, remove the battery safely, clean up any leaked liquid (while using protective gear) and replace it with a new battery.
Read: How To Tell If UPS Battery Needs Replacing?
Battery Corrosion
What it is: Corrosion happens when a material, such as the metal that makes up a UPS battery’s terminals starts to deteriorate.
Not only will corrosion cause the affected components to fail, but it can also lead to leaking in the case of a sealed UPS battery. That will happen as the components deteriorate to the point where they cannot keep the battery’s electrolyte safely contained inside.
How it happens: Corrosion in UPS batteries typically happens during overcharging. Overcharging causes excessive currents to enter the UPS battery. That will produce heat that can only escape the battery through its vents.
Heat and electrolyte that escape through the vent can then cause metal parts to corrode, leading to worse leakages later.
How to resolve it: First and foremost, dispose of the affected battery safely and replace it with a new one.
In the example above, the leaking’s root cause was overcharging. Overcharging occurs when the UPS electronic components, which control the charging and discharging functions, become faulty.
So, if your UPS has problems with its control board or other electronics, stop using the unit until you can repair it. That will prevent overcharging from happening.
Read: What Are UPS Battery Failure Symptoms?
Frequently Asked Questions (FAQs)
Here are a few questions and answers to help you better understand UPS battery leaks:
Can A UPS Battery Leak?
Yes, A UPS battery can leak. UPS units typically use sealed batteries. Still, those batteries have vents or safety valves through which heat and electrolyte can escape from inside.
Can You Use A Battery That Is Leaking?
No, you cannot use a battery that is leaking. Leaking battery electrolyte or fluid is dangerous to you and anything it touches.
What Do I Do If A UPS Battery Leaks?
When your UPS battery leaks, shut it down immediately. Disconnect any devices plugged into it, then disconnect the UPS from the wall socket. Use protective gear to remove the leaking battery and dispose of it safely.
Can A Leaking UPS Battery Explode?
Yes, there is a possibility that a UPS battery will explode if the safety valves or vents are blocked, and the pressure inside becomes too strong.
Why Are My UPS Battery Terminals Corroding?
UPS battery terminals corrode when electrolyte and excess heat escape through their safety valves or vents. The excess heat is typically caused by overcharging.
