October 2015 until June 2022 for me. Vehicle kept in a pole barn/garage unheated, plugged in on a timer during the winter; about 44k miles. 2016 Ram, kept on a tender when not running for a couple of days. Planning to pick up some new ones from Napa on Monday. Thought the new truck would be here before the replacements were needed; apparently KZLD status can last a while.