The fast charging data cable can be used for slow charging, but because the current of the fast charging data cable is larger than that of the slow charging data cable, when using the fast charging data cable, the phone will automatically detect the current size of the data cable and adjust the current size. For ordinary charging, it will adjust itself, even if the fast charging data cable is used, it will not affect the ordinary charging speed. However, if the long-term use of fast charge data cable charging on the slow charge will have some damage to the battery, it is recommended to use the correct charger and data cable according to the requirements of the device.
The fast charging cable can be used for slow charging, but the charging speed will be limited. Fast charging data cables are designed to provide faster current charging speeds and usually have larger wires and a thicker insulation layer, which makes it able to withstand higher voltages and currents.
However, when using a fast charge cable for slow charge, the current will be limited because slow charge devices can only charge slower current. Therefore, in this case, the charging speed will not be as good as using a slow charging data cable.