Running time: 3 hours. Charging time: 1 hour. Red charging indicator goes out when fully charged. Charge in any USB charger, laptop or other device with USB output. Contains internal polymer lithium ion battery. Bottle lights don’t like to be too hot or too cold. It’s always a good idea to keep your Bottle Light at room temperature. If too hot or cold they will not light for as long as normal, or shine as brightly.