Gate Opener Battery Reserve Calculator

Estimate how many days a gate opener battery will last during cloudy weather and low-sun periods.

Common questions

How long will my gate opener battery last if the solar panel fails?: A 7Ah battery typically runs a residential opener for 3–7 days of normal use with no charging, depending on cycles per day and gate weight.
What is a safe depth-of-discharge for a gate battery?: Sealed lead-acid batteries last much longer if kept above 50% state of charge. Design reserve to hit that floor, not 0%.
How can I extend battery reserve without buying a bigger battery?: Reduce cycle count with pedestrian mode, add a second 7Ah battery in parallel, or upgrade to a 12V AGM battery of higher Ah rating.
How do cold temperatures affect reserve?: SLA capacity drops roughly 20% at freezing and 40% at 0°F. Size your reserve for the coldest expected week.