Power bank has two regular standard of capacity , one is the battery capacity, one is the rated capacity. The 10000mah power bank, being labeled 10000mah/3.7v core capacity be converted to rated capacity 6500mah/5v.
Why exist this difference?
The most important reason is the conversion rate. Because most of power bank's battery voltage is 3.7V, and power bank needs to increase the voltage to 5V when charging the mobile phone, which making the power bank's conversion efficiency only 3.75/5=74%, Also include generated heat when battery voltage boosting, and various of wire consumption, Electricity and self-consumption. these points add up to account for 30%-40% of the power of the mobile power source.So the 10,000mAh power bank can really be used by us only about 6500mAh.
Brand Name: Kuulaa Battery Type: Li-polymer Battery Features: Digital Display Output Interface: Double USB Certification: CE Origin: CN(Origin) Input Interface: USB Type C Shell Material: Plastic Type: Portable Power Bank Max Input: 10W Color: Black White Feature 1: power bank, powerbank, poverbank, portable charger, portable battery Feature 2: portable charging, pover bank, power bank 10000mAh, mini power bank Feature 3: mobile battery, powerbank 10000, portable charger for cell phones Feature 4: Powerbank 10000mah, power banks, power bank 10000, usb bank Feature 5: Portable power bank, small powerbank, portable phone battery charger Feature 6: Power bank for phone, power bank 10000 mah, portable external battery Feature 7: Portable charger for mobile phone, powebank, power pack Feature 8: External battery telephone, battery pack for phone, battery bank Compatible Cellphone:: For iPhone Xiaomi mi Sony HTC LG Samsung Power Bank