My understanding of the 1C, 2C, 3C, etc. is that 1C=full discharge in 1 hour, 2C would be twice as fast or 1/2 hour and 3C would be three times as fast or 20 min. (1/3 of an hour). The faster charging limits the number of cycles. 1C would be what the battery is rated for as far as charge and discharge, going beyond the rating for the battery damages it and shortens it's life.