What is a power bank

A power bank is a battery pack that can store power and be recharged. Most power banks are portable that can be taken out. It can recharge people's cell phone, USB fans, speakers, Earbuds ,laptops or other electronic devices.

It is made of shell, battery cell and PCB boards. The shell's material mostly are plastic fireproof aluminum alloy. And battery cells commonly used are liquid lithium-ion and polymer lithium-ion batteries. The PCB parts are the managing center of a power bank. It controls the charging and recharging, fast charge or normal charge, over charging, short-circuit, over heating or other protections.

A good power bank can intelligently deliver power the devices need and adjust the current during charging, protect the battery to extend the lifespan and ensure the charging efficiency.