If a Z sensor is set to 15-minute intervals at perfect operating conditions, generally, the battery lifespan will be 4-6 years. If the Z sensor is set to 5-minute intervals at perfect operating conditions, generally, the lifespan will be 3-5 years.
"Perfect operating conditions" refers to primarily reliable connectivity with the gateway. If there is an inconsistent connection with a gateway, the Z sensor will expend more power searching for the gateway thus reducing the battery life.
Variables such as sensor attachments splitting data packets and the operating temperature can affect the lifespan.
Example: The batteries in a Z sensor operating in an ambient 20° Celsius environment will last longer
then the batteries in a Z sensor operating in a freezer 0° Celsius environment.
Z sensor batteries are replaceable, but be careful not to crack the battery cover.