Yes, you can connect 5V DC power from a USB power supply to a 3.7V BMS, but the following points should be noted:
- Voltage matching: The USB power supply BMS output voltage is 5 volts, while the original battery is connected to 3.7 volts. This means that the voltages do not match. In this case, you need to make sure that the BMS and associated circuitry can handle an input voltage of 5 volts. Otherwise, you may need a voltage adapter or regulator to ensure that the input voltage does not damage the BMS or related equipment.
- Current Limit: USB power supplies typically provide much more current than the maximum charging current of a 3.7-volt battery. Therefore, ensure that the BMS can handle the current from the USB power supply, and will not cause the battery to overcharge. If the BMS is not suitable for this current, you may want to consider adding appropriate current-limiting circuitry.
- Battery Status Monitoring: Due to voltage mismatch, the USB power supply BMS may not be able to accurately monitor the status of the battery. This can lead to problems such as undercharging or overcharging. Be very careful when using it.
In summary, it is possible to connect a 5V DC power supply to a BMS originally connected to a 3.7V battery, but it is necessary to ensure proper handling and configuration in terms of voltage, current, and safety. If you are unsure how to proceed, consult a professional or electrical engineer for advice.
MORE: If the battery pack configuration is changed from 4 cells to 4s/4p, will the 4s BMS still be required and can the same BMS continue to be used when the system is converted to 24V at a later date?
