Several days ago, a friend told me that “The e-cigarette I bought has two built-in unprotected 18650 batteries. The merchant said that they can charge directly without removing the battery. But I don't know if it will be dangerous to charge directly. How do I charge it properly?” Nowadays, many electronic cigarettes, flashlights and camera stabilizers on the market have built-in lithium batteries for power supply, and also provide direct charge.
For direct charge and desktop charge, which one do you prefer?
For direct charge and desktop charge, which one do you prefer?