If the LaCrosse is charged with usb interface, it is better to buy a car inverter and plug in a cigarette lighter to charge faster. Because the direct output current of the USB interface of the car is very low, which is almost half of that of the ordinary charger, similar to the charging of the mobile phone directly plugged into the USB interface of the computer, the charging speed will be much slower than the normal charging at home or the charging of the cigarette lighter. There are two ways to charge the LaCrosse: 1. Add an adapter to the cigarette lighter and charge the mobile phone. 2. The factory has USB interface. For the former, the battery of the car provides direct current, and the mobile phone itself also receives direct current. The cigarette lighter car is not responsible for converting alternating current into direct current, and the structure is simpler. As long as the quality of the adapter can be guaranteed, there will be no problem. However, the direct output current of automobile USB interface is very low, almost half of that of ordinary charger. Similar to charging a mobile phone directly into a computer USB interface, the charging speed will be much slower than normal charging at home or charging a cigarette lighter. Since the manufacturer has designed the USB interface, there will be no problem. In fact, if the subjects carefully observe, the electrical appliances of most models will be cut off when the car starts. Secondly, there is an IC chip inside the mobile phone to manage the charging current and voltage, so as to prevent the damage of unstable voltage and current to the mobile phone.