With proper maintenance, battery life can be predicted and replacements scheduled without interrupting your operations. These are IEEE and OEM recommendations for general maintenance:
How can you ensure UPS batteries are in good condition and have maximum holdover in power outage?
Comprehensive maintenance programs with a monthly inspection and more rigorous quarterly and annual checks
Re-torque all connections, as required
Cleaning the battery area, as required
You should have the UPS and its batteries thoroughly inspected and tested by a trained field technician. On smaller UPS models, you can often initiate a self test of the unit by pressing a button on the front panel.