Simple dry battery constant current charger circuit

In daily life, if there is no special charger for some rechargeable batteries , two diodes can be used to form the most convenient and quick simple charger, which can directly charge various rechargeable batteries. This kind of charger is 
 
a combination . The diode and the battery to be charged are directly connected in series to the power supply voltage, and the bulb current is used to charge the battery. Generally speaking, the charging current of this simple charger is about 50-150mA, which can basically meet the charging needs of ordinary batteries. Of course, it is worthy of full attention that since the charger is directly connected across the 220V mains power supply, special attention should be paid to safety during operation! See the diagram for wiring of circuit components.