The more power the battery has, the faster it will charge. For instance, you can fill a 10000mAh battery that is already 80 percent full in a few minutes. On the other hand, it may take ten hours or more to charge a 10000mAh battery at 0 percent. Don’t allow the battery to fall to zero. The Galaxy S21 features a 4,000 mAh battery while Samsung put a 5,000 mAh power pack into the Galaxy S21 Ultra. gets a bump from last year's S20 Plus, going from a 4,500 mAh power pack to a Smartphones with 5,000mAh battery or more are guaranteed to last a long time before needing a re-charge. Based on my experience, these smartphones usually last more A 10,000mAh power bank has an actual 6,660mAh capacity, which allows you to charge most new smartphones about 1.5 times. The size of a smartphone battery differs per device. While 2-year-old smartphones sometimes still have a 2000mAh battery, new devices have a 4000mAh battery. Make sure you check how large your battery is. Charging efficiency: Most power bank companies claim that your phone should last more than a day with 5,000 mAh. Therefore, we looked at battery packs within the 5,000-2,000 mAh range. Hello, I have a lipo 22.2 volt 6S 5000mah battery, what is the recommended charge rate for this battery? I have it set at about 2.6 amps and somehow it takes about 15 minutes to charge. After charging for a while my charger will start flashing CAPA, which means capacity. In general, though, you can expect a 500mAh battery to last for around 2-3 hours when used continuously at its rated capacity. So if you’re using a device that draws 100mA of current, you can expect the battery to last for 5-6 hours before needing to be recharged. first you would use P=V*I to convert cellvoltage and cell mAh into a Wh figure. then do the same for the rpi, 5v * lets say 1.5A to get 7.5W draw from the rpi. then just Wh/7.5W to figure out how many hours, assuming zero conversion losses. cVdQDfX.