UPS Battery Failure | The Leading Cause of UPS failure

You can’t predict downtime, so make sure you have systems in place that you can rely on to prevent disruption. The leading culprit of UPS failure, leading to the consequent downtime of your entire infrastructure, is its batteries.

There are 3 main factors that impact UPS battery life:

UPS Battery Temperature Temperature

Most UPS batteries are lead-acid, and the leading cause of UPS battery failure is incorrect temperature or temperature variances. For optimum performance, the ideal temperature for UPS batteries is 22-25ºC. Any variation alters its performance. Increased battery capacity is reached between 22-25ºC but whilst this enhances battery performance, it also reduces the battery life – so there is a fine balance between battery life and battery performance, and it is important this balance is understood and managed correctly

Did you know that your battery life is halved for every for every 8.3ºC temperature rise above the ideal 25ºC! So if your battery is operating at 33ºC you are at risk of having your battery life expectancy halved, and with a lead battery life generally being between 5-10 years this can have a significant impact on the life of your battery.

UPS Battery Empty Naturally, batteries don’t last forever

Even if all guidelines to maintaining UPS batteries are followed; their natural ability to store and deliver power steadily decreases over time. All batteries require maintenance and eventually need replacing.

UPS Battery Discharge Discharge Cycle

During a power failure, your UPS will operate on battery power. When power is restored or the switch to the generator is complete, the battery is recharged for future use. This is called a discharge cycle. Each discharge and subsequent recharge reduces the relative capacity of the battery by a small percentage. The length of the discharge cycle determines the reduction in UPS battery capacity. UPS batteries can only undergo a maximum number of discharge/recharge cycles before the batteries must be replaced.

Ideal conditions for your UPS battery

The life of a UPS battery is based on its design life. This means, how well the battery can potentially perform when operating under ideal battery conditions.

Regular servicing and maintenance will monitor the conditions your battery sits within, and potentially extend the battery life. A badly maintained or out of date system can affect your UPS battery, but unfortunately, without testing them regularly, you are only going to find out they don’t work when they fail.

UPS batteries need to be checked and tested every 12 months and fully load-tested every two years. Because batteries are such critical elements of your standby power system, it is crucial that you are aware of what their operational capacity is and how much deterioration there has been since the battery was new. You will also want to know that your batteries are fully charged.

With proper maintenance, battery life can be predicted and replacements scheduled without interrupting your operations.

Remote monitoring service

We also offer a remote monitoring service. This service detects any changes or errors in your system, immediately informing relevant personal. This early warning alert can prevent the situation from reaching a critical point.


So, in summary, if you look after your batteries, they will work effectively in the event of a power outage, if not, they are likely to fail – potentially with catastrophic consequences to your business.


If you would like to enquire about any of our maintenance services, get in touch and we will get back to you within 24 hours.

01993 708855