The UPS battery has an average life span of about 2 years depending on how often the unit is put into use during the power outages. Often, when the battery is getting low, the UPS will beep or have a blinking light. If you believe your battery may be running low, refer you your user's manual for your models specific features.
If your battery needs to be replaced, please contact Storage Battery Systems Inc. (SBS) to get a new battery, at 262/703-5800 or toll free at 800/554-2243. They may also be contacted by email at the below link:
http://www.sbsbattery.com/contact.htm
The batteries in our Uninterruptible Power Supplies (UPS) are lead-acid and care should be taken in their disposal. If you do not have a method of proper disposal in your area, Storage Battery Systems can also assist in the proper disposal of lead-acid Batteries.
Should you still have questions, please ask us by clicking on the "Ask a Question" tab above.