New user-battery life - ATN Thor LTV 5-15x Thermal Imaging Rifle Scopes Gen 5

Little concerned with battery life. Only lasted about 45 minutes. This was during sighting in the rifle so it was heavy use scrolling through the menu and options also very cold. I’m going to give it another try and hope for better results if not it’s gonna have to go back. 45 minutes won’t cut it. Also learned this needs a offset scope at least for me to get proper eye relief so there’s another $100 on top.