Charging for a while is a fast charge for a slow reason:
The output voltage of the charging bank is insufficient. This is determined according to the principle of charging, it must be high voltage flow to low voltage, the mobile phone is generally 3.7V, the mobile power supply lithium battery is 3.7V, so it is flat, so the mobile power supply will be boosted to 5V when the output voltage, so that high voltage flow to low voltage, charging
Is the cause of fast charge or data line aging