The Inogen One G3 16 Cell rechargeable battery can last up to 8 hours at a flow setting of 2 when it is fully charged. The 16 cell battery is a great battery source when you need more battery life for extended vacations or long flights.
The battery can be charged in 6 hours and will charge while the Inogen G3 is connected to an AC or DC power supply. It can be charged with the Inogen One External Battery Charger as well.
I purchased this batter when I purchased my Inogen 3 last January and it really helps in my traveling. I do not need to carry extra batteries and it will last for the day. When flying, I will top off the battery during times between flights. The airlines want you to have power during flight.