... by solar or AC adaptor ; 2,Battery: 3.5Ah/4v rechargable Lead-Acid battery;3,Charging time: 5V 500ma adaptor charge 7 ... -8 hrs, and solar charge 2 days (under standard sunlight intensity) ;4,Two ... hours, Level 2(110lm) working 8hours when fully charged, and charge one day, level .1 working 5.5hrs, level 2 working ...