ICD battery life varies depending on the device model, how often it delivers therapy, and how it is programmed. The typical range is 5 to 10 years, though some devices last longer, and higher therapy usage can shorten battery life.
Your device clinic monitors battery levels at every check-up and will give you plenty of notice when replacement is approaching. There is no risk of the battery running out without warning. When the time comes, replacement is a relatively minor procedure, usually simpler than the original implant, as the leads can often be reused.
For a more specific estimate based on your particular device and settings, ask your cardiologist or device nurse at your next appointment. You can also read more on our page about living with an ICD.