Batteries Overheat. Are You Prepared?

So you have taken the necessary steps to protect your equipment by installing a UPS system, but have you given thought to the batteries the backup equipment runs on?


A room temperature of as low as 75 degrees F can contribute to battery temperature issues.

Does the housing for your batteries feel hot to the touch? There are several causes that can lead to a battery overheating.

  • Excessive room temperature

  • Incorrectly set voltage levels on the charger

  • Shortened cells due to manufacturer’s defects

  • Shortened cells cud to aging, excessive load cycling, lack of maintenance, etc

  • Lack of consistency in the relative condition or age of the jars

When any of these issues occur, it can lead to what is known as thermal runaway.


Thermal runaway is a situation where an increase in temperature changes the conditions in a way that causes a further increase in temperature. It is a feedback loop that can easily cause malfunctions.

What can happen when a THERMAL RUNAWAY occurs? 

One of the first signs of thermal runaway is that the batteries become hotter than normal. Initially, the batteries will show signs of heat, they may begin to bulge and ooze as well. Next, the oozing and bulging will increase. Ultimately, the worst-case scenario can occur – a meltdown. If left unnoticed and unattended, the results can range from a localized effect to an entire infrastructure catastrophe.

It is important to note that just because a battery says “maintenance free” does not mean that they will operate perfectly forever. That is why it is important to have your batteries checked at a minimum of once a year.

Scheduling preventative maintenance is worth it, especially when catching batteries at the early stages when they begin to show signs of heat can protect not only your loads, but also your facility as well.

You are invested in keeping your equipment safe, make sure you are covering all of your bases.