The batteries of the LOQED Touch Smart Lock will last 9 to 12 months. With the LOQED Power Kit you have everything you need to never change the batteries of your lock again. Simply plug in the provided charger as soon as your LOQED Touch Smart Lock notifies you the batteries are running low. The charger cord is three meters long, so you don't even need to have a socket nearby. The LOQED Power Kit includes 8 rechargeable batteries.