What is PCB BMS composed from?
Normally lithium battery (include lithium ion battery and lithium iron phosphate battery) requires protection circuit to protect battery while using.
The protection circuit board is called PCB, PCM (protection circuit module) or BMS (battery management system). A BMS is a higher level PCB which may contains communication protocol, support lcd display of temperature, SOC etc.
PCB and BMS are mainly composed of electric circuit. They accurately monitor lithium battery cell voltage and current while charge and discharge at ambient environment -40°C ~+85°C, It can shut off the battery when something is abnormal. A BMS usually contains control IC, MOSFET , resistor, capacitor and some auxiliary parts.
The control IC (integrated circuit) is a set of circuits that is constructed on a single semiconductor, wafer, or chip. It controls the MOSFET under all normal conditions to make lithium battery cells and external circuits conduct. When voltage or current of lithium battery cell exceed specified values, it will turn off the MOSFET right away to protect batteries and devices
MOSFET (Metal Oxide Silicon Field Effect Transistors) is used to switch or enlarge voltage in circuits. It is a device that control voltage and it is composed with several terminals. Source, Gate, Drain and Body
Resistors are passive two-terminal electronic unit that implement electronic resistance as circuit element. In electrical circuit, resistor is used to decrease current flow, adjust signal level to divide voltage.
Capacitors are electronic components that draw energy from lithium battery and store power energy. Inner side, the terminal connects 2 metal plate separated by non-conducting substance. When the capacitor activates, it will rapidly release electricity.
3.7V 1S Lithium Ion 18650 Li-ion Battery Pack with PCB at Top
Rechargeable 18650 3.7V Lithium Ion Battery with PCB at Side
18650 Rechargeable Lithium Battery Pack 3.7V 2600mAh Button Top with BMS PCB
