The reason I asked was to help determine how to answer you. A 6600ma liion battery can be SAFELY charged at 1/2C, which would be about 3A or 3000 Mah. At 6A, it should take less than 1 hour to full charge. Be sure and use a charger designed to Liion batteries, as the peak shutoff point is different from other type(including lipo) batteries. If you have a RC Hobby shop nearby, there are a number of chargers on the market for Airplane and wheeled vehicle batteries that have settings for liIon batteries. Most are designed to work from a 12V source.
