Functionality:
A 3S BMS monitors and controls the charging and discharging of three series-connected battery cells. It ensures each cell operates within safe voltage limits, prevents overcharging or over-discharging, balances cell voltages, and may include features like temperature monitoring and communication interfaces.

Voltage Range:
Depending on the type of batteries (e.g., lithium-ion), a 3S BMS typically handles a voltage range that corresponds to three series-connected cells, such as from around 9V to 12.6V for lithium-ion batteries.

Applications:
Such BMS configurations are commonly used in various applications, , portable electronics, solar energy storage systems, and more.
Voltage Rating:

Operating Voltage:
Typically supports a range suitable for 3 series-connected cells. For lithium-ion batteries, this would typically be from around 9V to 12.6V (3.0V to 4.2V per cell).

Current Handling:
Charge and Discharge Current: Specifies the maximum current the BMS can handle during both charging and discharging operations. This could range from a few amps to tens or even hundreds of amps, depending on the application.

Protection Features:
Overcharge Protection: Prevents individual cells or the entire battery pack from exceeding safe voltage limits during charging.
Overdischarge Protection: Ensures cells do not drop below safe voltage levels during discharge, which can extend battery life and prevent damage.
Overcurrent Protection: Safeguards against excessive current draw that could damage the cells or the BMS itself.
Temperature Monitoring and Protection: Monitors battery temperature and may initiate protective measures if temperatures exceed safe thresholds.
Cell Balancing: Equalizes the voltage of individual cells within the battery pack to ensure they charge and discharge evenly, maximizing pack capacity and longevity.