1, if the car charger is not compatible with your mobile phone will not be charged.
2, not fully compatible, charging current will be small.
3, if compatible, the car charger quality is too poor, the output current is too small, the charging effect is not obvious, it will feel not charged.
Extended data
The car charger uses the car cigarette lighter as a power outlet to charge the phone directly. Since the voltage provided by the car is low, only overload protection circuits are needed inside the car charger. The front end of the car charger socket is designed with a safety tube, and when the current exceeds the acceptable range of the overload protection circuit, the fuse is immediately blown and plays a protective role. Note: It must be charged when the car engine is started!