How Long Does A 20 Volt Battery Last?
How Long Does A 20 Volt Battery Last? Depends on your battery size. A compact 2ah battery should last about 6-8 hours, so you get about 3-4 hours per ah. You will probably run out of propane first, propane will last 6 hours on high, 14 hours on low. 5 of 6 found this helpful.