Stationary batteries have a limited life. Batteries that are used in an uninterruptible power supply (UPS) system slowly degrade over time.

For your UPS system to operate effectively and efficiently, it is vitally important for batteries to be in a good state-of-health.

To ensure that your batteries are healthy and last as long as possible, it is important to understand what factors affect battery life and what you can do to extend that life.

Factors affecting battery life
There are many factors that affect battery life in UPS systems.

  1. Battery Chemistry:  Over time, that battery’s ability to store and deliver power deteriorates. This is largely due to its chemistry. This includes expansion and corrosion due to oxidation of the grid and plates, physical changes in the active material, and loss of the active material.
  2. Temperature: Temperatures that are too high or too low reduce battery life. An ambient temperature of 25C/77F is recommended at all times.
  3. Cycling: The catch 22 is that using the batteries actually reduces their life expectancy. If there is a utility failure and the UPS kicks in the battery power, batteries will be discharged and then recharged. Each discharge and subsequent recharge reduces the battery’s capacity and, therefore, lifespan. Overcharging and undercharging have the same affect.
  4. Lack of Maintenance: Regular maintenance is a necessity for maintaining battery state-of-health. Without maintenance, batteries may experience resistance at the terminals, improper loading, reduced protection, and premature failure.

What you can do to extend battery life
Although battery deterioration is unavoidable in the long-term, there are things that you can do to extend the life of your batteries as long as possible. These are encompassed in a regular maintenance schedule.

This maintenance should include:

  • Inspection of batteries for signs of corrosion or leakage.
  • Cleaning the terminals to prevent corrosion build-up.
  • Checking terminal connections to ensure they are tight.
  • Checking electrolyte levels and adding water as necessary.
  • Testing conductance levels so that bad batteries can be removed promptly, so as not to affect other batteries in the string.

Following these simple steps on a regular schedule can greatly impact the life of your UPS batteries.