1500mAh is 1,500 milliamp-hours, its balacisly a measurement of how long the battery might last. larger number is more life. i wouldn't worry about putting 6v from these panels into your phone, as the nominal voltage for a USB cord is around 5v anyway. the phone will be the smarts of your charger, it should turn the charge off when they're done. as for the amperage, the solar lights' panels are probably puny and cant be more than 300mAh each. this will not cook your phone.