USB charger in daily life is very common, USB charger is connected to the computer USB port, directly by the computer USB charging, no large transformers, structure is very simple, more convenient than the original charger a lot.
However, no matter what kind of electronic equipment, will have a certain service life, USB charger also has a certain life.
Generally speaking, the effect of rechargeable battery will accumulate with the effect, which will reduce the actual capacity of the battery and reduce the side effect caused by the memory effect.
Ni-CD battery effect is most obvious, it is recommended that the use of this type of battery friends, you need to repeatedly use 5 to 10 times before you can do a discharge.
Ni-MH battery is different, can be used repeatedly 20 to 30 times before discharge. The capacitor in the USB charger is the nickel-hydrogen electrolyte, so it takes a long time to put the electricity in the process of use, thus having a long service life.