Signs Indicating the Need for UPS Battery Replacement

Posted on Mar 30, 2024 by

In today's digitally-driven world, uninterruptible power supply (UPS) systems are essential for maintaining the operational continuity of businesses and organizations. At the core of these systems are the UPS batteries, which provide backup power during power outages and voltage fluctuations. However, UPS batteries can degrade over time, which compromises the reliability of the entire UPS system.

In this article, we will explore the reasons for UPS battery replacement and discuss factors that affect the replacement of UPS batteries.

Reasons for UPS Battery Replacement

UPS batteries are crucial for maintaining the reliability of data center operations, primarily in the following two aspects:

Reduce Failure Risks

UPS systems are crucial for maintaining the reliability of data center operations. As batteries age, their capacity decreases, increasing the risk of failures during power outages. Timely replacement of UPS batteries helps ensure a continuous power supply, reducing costly downtime and the possibility of data loss.

Ensure Optimal Performance

New UPS batteries offer optimal performance and reliability. They offer adequate standby power, minimize the danger of data loss, and sustain operations amid power interruptions. UPS battery replacement aims to minimize the impact of power-related interruptions on business continuity as much as possible.

Factors that Influence UPS Battery Replacement

Ambient Temperature

The rated output capacity of the battery is based on an environment of 20-25°C. Changes in ambient temperature will alter the current capacity of the battery, reducing its lifespan. If UPS batteries operate for extended periods at higher temperatures, their lifespan will be shortened. For instance, continuous usage of UPS in industrial or outdoor environments, or hot climates, may lead to issues.

Generally, it is accepted that for every constant 10°C increase in temperature above this recommendation (20-25°C), the battery service life will be halved (reduced by 50%). Refer to the image below for an indication of how rising ambient temperatures can impact UPS battery service life.

UPS battery service life

Discharge Frequency

The way a UPS battery is used directly affects its lifespan. Batteries that experience high discharge rates, frequent power outages, or long periods of deep discharge will be under greater stress and age more quickly. The continuous cycle of charging and discharging will deplete the battery's capacity over time, with the number and duration of discharges affecting the battery's ability to supply power. Generally, the more frequent and deeper the discharges, the shorter the battery's lifespan.

Battery lifespan

Although the generally accepted range for battery lifespan is 3 to 5 years, it still depends on your operating environment and how you utilize the batteries. Additionally, batteries are electrochemical energy storage devices that convert chemical energy into the electrical energy required for UPS operation. Even with recharging, the chemicals within a battery diminish over time, leading to a decrease in the power they can provide and a shorter duration for a given load.

Load Size

If the battery does not have enough power to meet the load capacity, it will shorten both its runtime and lifespan. It is essential to check your power consumption based on your available time requirements and adjust the UPS or battery type to meet your needs.

If you are using two UPS units for redundancy, or if your equipment sources power from both the "main" supply and UPS concurrently, be sure to use monitored or metered PDUs to prevent overloading the UPS during power outages.


Regular maintenance is crucial for maximizing the lifespan of UPS batteries. Scheduled inspections, testing, and preventive maintenance procedures help to detect issues early, allowing for timely corrective measures. Importantly, the battery maintenance should be timely, involving discharge and charge cycles.

Additionally, if there is an uninterrupted power supply for extended periods, every three months the device should be manually disconnected from the power source using the battery, allowing it to operate, to activate the battery and prolong its service life.


In conclusion, UPS battery replacement is a critical aspect of maintaining the reliability and performance of UPS systems. By understanding UPS battery replacement factors and maintaining them properly, businesses mitigate power interruption risks, ensuring uninterrupted critical equipment operation. For detailed information about Uninterruptible Power Supply, please read this article: What is Uninterruptible Power Supply or UPS?

You might be interested in

See profile for Sheldon.
Decoding OLT, ONU, ONT, and ODN in PON Network
Mar 14, 2023
See profile for Irving.
What's the Difference? Hub vs Switch vs Router
Dec 17, 2021
See profile for Sheldon.
What Is SFP Port of Gigabit Switch?
Jan 6, 2023
See profile for Migelle.
PoE vs PoE+ vs PoE++ Switch: How to Choose?
Mar 16, 2023
See profile for Moris.
How Much Do You Know About Power Cord Types?
Sep 29, 2021