It's not safe.
Because the lithium battery has a charging control chip, the charging voltage and charging time need to be adjusted according to the output current of the charger when charging to ensure charging safety and battery life.
The output current of the switching power supply fluctuates greatly, which cannot meet the charging requirements of the lithium battery, which can easily lead to overcharging or overcharging of the battery, resulting in safety accidents.
At the same time, the circuit structure of the switching power supply is more complex, involving the circuit connection of high voltage and high power, and improper operation will also cause short circuit, fire and other risks.
It is recommended to use a special charger for charging to ensure charging safety and battery life.