Inogen One Portable Oxygen Battery Duration: Oxygen Flow Setting Single 8 Cell Battery Double 16 Cell Battery 1 lpm Up to 4.5 hours Up to 9.5 hours 2 lpm Up to 4 hours Up to 8.5 hours 3 lpm Up to 3 hours Up to 6 hours 4 lpm Up to 2 hours Up to 4 hours 5 lpm Up to 1.7 hours Up to 3.3 hours