How long should a lead acid UPS battery last?

Lead acid batteries are typically designed for either 5 years or 10 years. This is known as their design life. Battery life is also dependent upon a number of other factors including ambient temperature, charging technique and the number of charge/discharge cycles. A typical 5-year design life battery will require replacement around years 3-4 of operation and a 10-year design life battery around years 7-8.