Normally the AGM batteries have a life span of 3 to 5 years or 100 – 250 charge cycles before you reach the 50% capacity after a charge. It is all about how deeply you discharge the battery pack. If you operate under full discharge – recharge conditions, your battery pack may last 1 – 3 years. On the other side, with the 3400 Hybrid system the batteries only go down to 60% of the capacity before they recharge and this should provide 5 years of continuous use under light to medium loads. Leaving your trailer unattended and unpowered may be the most significant battery abuse. Our 2018 model uses a low voltage full disconnect functionality that further extends the battery life.