You can charge the device with your laptop or PC or with 5V DC, 1A USB wall charger. When it is charging, the battery symbol in the device illuminates. Once the battery is fully charged, the battery symbol will stop glowing. After two hours of use or the battery charge is less than 50%, then only the device accept the charge and battery symbol illuminates.
Many customers were call very next day and saying that their device is unable to recharge. Unlike the mobile phones or emergency lamps this device will not accept charge until its charge is less than 50% of battery capacity and this is for preventing overcharging and for increase the battery life.
When the battery charge is too low, battery symbol will flash with red light. So please re charge the device immediately.