In the US, Oregon state law (ORS 497.297) requires a 10 year smoke alarm battery. Michigan state law (MCL 125.1504c) requires a 5 year smoke alarm battery which can be satisfied by some alkaline batteries but they recommend a Lithium 9V battery. Louisiana state law (R.S. 40:1573 and 1581) requires a 10 year sealed lithium battery smoke detector in one or two family dwellings sold or leased after January 1st, 2011. Many other towns, cities, and municipalities also require 10 year smoke alarm batteries. Please contact your local authorizes to learn more.