Uninterruptible Power Supply (UPS) systems are the unsung heroes of critical power infrastructure. But just like any power solution, their reliability hinges on one crucial component: the battery lifespan.
At BCL Power, we’re often asked two key questions: “How long do UPS batteries last?” and “Can I replace them myself?”.
In this blog, we’ll unpack what determines battery lifespan, the risks of waiting too long, and why professional UPS battery replacement is the smart and safe choice.
Understanding UPS Battery Lifespan
Most UPS batteries have a typical lifespan of 3 to 5 years. However, that estimate depends on several influencing factors:
1. Environmental Conditions
Heat is the enemy of battery life. Batteries kept in environments exceeding 25°C can degrade much faster. Even a consistent 10°C increase above this can halve the battery’s expected service life.
We recently replaced UPS batteries in a server room where the cooling system had failed over a summer weekend. The temperature peaked at 35°C for just 48 hours – yet within a year, battery capacity had dropped by nearly 40%.
2. Usage and Load
Frequent discharges, high loads, and improper sizing for the connected equipment can all shorten a battery’s life significantly.
A manufacturing site relied on its UPS during multiple short power cuts every week due to a local grid issue. After only two years, the batteries were already showing signs of sulphation and required replacement well before the expected timeline. This example highlights how repeated use under high demand, even over a short period, can accelerate battery degradation, especially if the system isn’t properly sized or maintained for the usage pattern.
3. Maintenance and Monitoring
Without regular testing and monitoring, battery issues often go unnoticed until it’s too late. Proactive UPS maintenance is essential to catching early signs of degradation.
During a routine SFG20-compliant maintenance visit for a healthcare facility, our team identified two battery blocks with high internal resistance. Replacing them immediately avoided a complete string failure during a later mains outage.
The Risks of Delayed Replacement
Aged or weakened UPS batteries can lead to:
- Unexpected downtime during a power cut
- Reduced backup time, leaving critical systems exposed
- System-wide failure, particularly in data centres, healthcare, or industrial settings
- Safety hazards due to leaking or swelling batteries
In short, delaying battery replacement can turn a reliable UPS system into a point of failure.
Can You Replace UPS Batteries Yourself?
Technically, some UPS units are designed for user-replaceable batteries – but that doesn’t mean you should.
Why professional UPS battery replacement matters:
- Correct battery matching: Not all batteries are created equal. Installing the wrong type or model can cause long-term damage.
- Safe disposal: UPS batteries must be disposed of in accordance with environmental and safety regulations.
- Thorough testing: At BCL Power, we don’t just swap the batteries – we test the entire system to ensure it’s operating at peak efficiency.
- Warranty protection: DIY replacement may void manufacturer warranties.
When Should You Act?
We recommend planning UPS battery replacements every 3–5 years as part of a structured maintenance schedule. But don’t wait until year five – watch for signs of ageing such as:
- Audible alarms or system alerts
- Reduced backup time
- Visible swelling or corrosion
- Increased system heat
Trust BCL Power to Get It Right
With decades of experience in UPS systems and battery technology, BCL Power offers proffesional guidance, installation, and maintenance services to ensure your systems are never caught off guard.
Need a battery check or quote? Get in touch with the BCL team today and take the guesswork out of UPS battery replacement.