answer:If you’re running the battery down completely, you’ll likely need to wait until the charger can charge the battery enough so that it will boot up. You might want to carry an extra battery with you if this happens often. You can buy one for $14. Then, if you kill the battery, just swap in the replacement and you’ll be good. You can also splurge for an extra charger, so you would be able to charge the extra without the phone. You can get this whole set for $25. It is a charger and 2 extra batteries.