In case your device takes more time to be charged up 100% by a Sunslice charger, this can either be due to a defaulting charger or because of inherent technical specifications of your device.A smartphone with a larger battery, for example, will take longer to be charged, than a smartphone with a small battery. With time, smartphones integrate larger and larger batteries, which causes longer charging times for recent smartphones.We constantly try, through enhanced R&D, to make our products evolve with the electronic developments on the market.