With the increasing application of lithium battery products, there are more and more accidents caused by the use of lithium batteries. In order to ensure the safety of product use, BMS has become a key component in the application of lithium batteries. The system can not only improve the safety of the product, but also increase the service life of the product.
The R&D department of SUNDAWN battery has conducted in-depth research on BMS for many years. Different BMS functions are different. The main functions of BMS on the market usually include charge and discharge and monomer balance management.
What are the main functions of our self-developed BMS ? As shown below,
Monitoring function is the most basic function of BMS, which improves reliable data for management function. The monitoring content includes the voltage, current, temperature and other parameters of the battery.
Protection functions include overcharge protection, over discharge protection, short circuit protection, over current protection, over temperature protection, balanced protection, etc.
Overcharge protection—When charging the product, when the battery reaches the highest voltage (4.2V), the BMS will automatically turn off the power, indicating that the battery is fully charged and will not continue to charge, thereby forming overcharge protection.
Over discharge protection—When the battery is almost used up and the voltage reaches the lowest value, the BMS will automatically shut down, and the product can no longer continue to discharge. The product will automatically shut down to form an over-discharge protection.
Short circuit protection—When the battery is accidentally short-circuited, the BMS will automatically shut down within a few milliseconds and will no longer be powered. At this time, even if the positive electrode and the negative electrode are in contact with each other, it does not matter, forming a short-circuit protection and will not cause an explosion.
Over current protection—When the battery is discharged, the BMS will have a maximum current limit. When the discharge exceeds this current range, the BMS will automatically shut down.
Over temperature protection—When the temperature exceeds the set range, the BMS will still disconnect the circuit and stop working.
Balanced protection—Divided into active equilibrium and passive equilibrium, active balancing is to balance by transferring power, high efficiency and low loss, passive equalization is generally through resistance discharge, discharge the batteries with higher voltage and discharge them in the form of heat, so as to obtain more charging time for other batteries.
The metering function is to dynamically report the SOC status of the battery during use. In theory, there is a certain corresponding relationship between the voltage and capacity of the battery. The SOC data during use and the theoretical SOC data are compared to judge the battery life span.
The battery status is connected to the outside through the interface and communication protocol, and the single cell can be transmitted to the terminal and displayed, realizing the function of automatic control or remote control.