A:Answer With electricity, everything is dependent on the draw of energy from you devices used.
So, to answer your questions one by one - you mentioned that you have a phone. Depending on the size of your phone, it can likely charger your phone about 4 times fully.
If you are powering a low wattage LED light, those don’t draw a lot of wattage you may be able to power that for 10-15hrs - it just depends on the power of the light.
The good thing is, the Jackery has a light on it. In an emergency it may be best to just use that light. It will be bright and effecient and save power.
No matter how you use the Jackery, it will alway tell you how much time you have left with what you have currently plugged in.
I hope that helps.
