What is the best portable charger?

What is the best portable charger? Perhaps lots of consumers believe that the best portable charger must have the best battery cell, in which case larger capacity can be offered and the charger last longer. That’s correct. Indeed battery cell plays a very important role. However another factor of consequence, the PCB is usually being neglected by us.

As the power management system, PCB is the brain of the portable charger. It protects portable charger smartly and efficently. The PCB is in charge of the actual conversion efficiency, various safety protection mechanism, and stability of the output amount.

A good PCB should have the following functions.

1. Protection.
Lithium battery cell, no matter lithium-ion or lithium-ion polymer, has a disadvantage of fearing of being over-charged and over-discharged. If the battery is being discharged lower than 2.7V, or being charged higher than 4.2V, it will damage positive pole and negative pole permanently. So a good PCB must have the fuction of anti-overcharging and anti-overdischarging.

2. Voltage boosting.
Generally voltage of the Lithium battery is 3.7V, but our phone, PSP, IPAD, MP4, or camera need a charging voltage of 5V, so a voltage boosting system is need. This job is done by PCB. When boosting the voltage, the charger will get a power lost. Good chargers lose 20-35% of power and the worse ones may lose more.

3. Battery charing protective IC.
A good PCB has the charging protective IC, but some manufacturers don’t use it for cost saving. A PCB with the protective IC can not only protect the charging but also detect the temperature. Once it’s too hot, the PCB will do something such as cutting power off to protect the battery.

4. A good PCB can supply a stable and large input and output current.

Here now we can conclude that to choose the best portable charger, PCB is good or not is as important as battery cell is.