[…] However, experts assure that, unless the cell phone has a technical fault, fast charging does not harm the battery because the process occurs in two phases. First, a large voltage is applied to the battery, so that it charges up to 50-70% in the first 15 to 30 minutes. In the second stage, the cell phone takes longer to charge because manufacturers reduce the charging speed in the last 20 or 30% so that the battery is not damaged, Teknofilo explained. …