Without a consistent and dependable power source, a robot cannot operate steadily. But who is the silent protector of the robot's power system? The Battery Management System (BMS), which is the foundation of the robot's energy management and essential to guaranteeing its steady operation, is the answer. It is in charge of overseeing and maintaining the robot's battery system, which enables it to function effectively in a range of challenging settings.

Explore the working principle of BMS system

Three essential features of the BMS system—parameter monitoring, equalization management, and safety protection—ensure the steady operation of the robot's battery system.

(1) Monitoring of parameters: All-around protection Using a range of high-precision sensors, the BMS system continuously measures the battery's voltage, current, temperature, and other important factors. These characteristics, which represent the battery's operational state, are comparable to its "health indicators." For instance, the BMS system will precisely measure the voltage of every battery unit when it comes to voltage monitoring. The BMS system can comprehend the battery's charging and discharging conditions and identify any potential overcharging or overdischarging risks by using real-time voltage monitoring. Equally crucial is current monitoring, which enables the BMS to determine the battery's working condition and energy usage as well as its charging and discharging currents. The battery's discharge current will rise when the robot is operating at high loads. By keeping an eye on the current, the BMS system may promptly modify the battery's output power to guarantee the robot's regular operation. Battery life and performance are also significantly impacted by temperature. The battery will produce heat during charging and discharging, and if the temperature rises too much, it could reduce battery performance, diminish its lifespan, or possibly result in safety incidents. When the battery temperature rises above the safety threshold, the BMS system's temperature sensor will always monitor the battery's temperature change and take appropriate cooling actions, like turning on the fan or modifying the charging and discharging plan, to make sure the battery is safe to use.

(2) Equalization management: certain batteries are always undercharged or discharge more quickly than others, which is truly a phenomena known as battery imbalance. Let the batteries "go hand in hand" while using battery packs. The overall performance and lifespan of the battery pack will be impacted when each battery monomer is in an inconsistent state. Battery imbalance can be caused by a variety of factors. First off, the starting capacity of each battery monomer, internal resistance, and other factors may vary during the production process because of process restrictions. A growing performance disparity between batteries will be the consequence of these minor variations adding up over time. Second, the battery will also be affected by the environment in which it is utilized. For instance, the efficiency of charging and discharging batteries will vary depending on the temperature, which will further worsen the disparity across batteries. The BMS system uses equalization management technology to address this issue. Active equalization and passive equalization are the two primary categories of equalization management technologies. By attaching resistors to the cells with higher voltages and allowing them to use the extra energy, passive equalization, which is similar to "peak shaving and valley filling," causes the voltages of all the cells to converge. Although this method is straightforward and inexpensive, it uses more energy and lowers the battery pack's energy consumption. In order to achieve energy equalization between battery monomers, active equalization is more clever and effective; it functions similarly to a "energy mover" by transferring energy from the battery monomer with a higher voltage to the battery monomer with a lower voltage. This method not only increases the battery pack's energy efficiency but also speeds up battery equalization and prolongs battery pack life. In order to keep all of the batteries in good condition and offer steady power support for the robot's operation, for instance, the power of high-energy batteries is transferred to low-energy batteries using inductors, capacitors, and other components. Naturally, this method is more complicated because it involves more algorithms in addition to more system components.

(3) Safety defense: the "firewall" during emergencies Overcharging, overdischarging, overcurrent, short circuit, and other irregularities may occur in the battery when the robot is operating. If these anomalies are not addressed promptly, they could pose major risks to the robot's and the environment's safety in addition to damaging the battery. Similar to a strong "firewall," the BMS system can act swiftly to protect the robot and battery in an emergency. The BMS system will instantly notify the charge controller to halt the charging process and guard against battery damage from overcharging when it detects that the battery voltage has surpassed the predetermined charging cut-off voltage, or overcharging. In order to further guarantee charging safety, the BMS system can optionally set a charging time restriction. If the charging time reaches the predetermined threshold, it will stop charging even if the voltage does not surpass the cut-off value. Regarding over-discharge protection, the BMS system will promptly cut off the discharge path to stop the battery from continuing to discharge when the battery voltage drops below the predetermined discharge cut-off value. In order to more precisely identify whether the battery is about to be over-discharged and to take preventive action beforehand, the BMS system will also employ algorithms to estimate the battery's condition, such as the state of charge (SOC) and state of health (SOH). On the other hand, overcurrent protection means that the BMS will take immediate action to limit the current when it detects that the battery's charging or discharging current exceeds the safe range. For instance, it may lower the current level by adjusting resistors or switches in the circuit to prevent the risk of overcurrent causing battery damage, heating, or even fire. The BMS system will quickly cut the circuit in the unfortunate event of a short circuit in order to prevent the dangerous repercussions of a short circuit and cease the irregular current flow. Additionally, certain BMS systems have hardware protection circuits, such fuses, etc. In the event that software protection fails, hardware protection can serve as the last line of defense to ensure the safety of the battery and the robot.

What advantages can a good BMS bring

(1) Increase battery life：By implementing a BMS system that successfully reduces battery loss and greatly increases battery service life through acceptable charge and discharge control and equalization management. The BMS system will determine the best charge/discharge plan for charge/discharge control based on the battery's properties and the usage environment. To prevent overcharging and reduce battery loss, for instance, it uses the constant current-constant voltage charging method, charging the battery with constant current first and then switching to constant voltage charging when the battery voltage reaches a specific value. To keep the battery from over-discharging and safeguard its performance, the BMS system will regulate the discharging current during discharging based on the battery's remaining power and load requirement.

(2) Improving security: safeguarding the robot Robot operation requires safety, and the BMS's numerous safety prevention systems efficiently lower the chances of battery failures, enabling the robot to operate dependably and safely in a variety of situations. One could argue that the BMS system's overcharging protection feature is essential. Battery heating, bulging, or even explosion may result from the chemical reaction inside the battery intensifying if the charge is maintained after it reaches a particular point. When the battery voltage reaches the predetermined charging cut-off voltage, the BMS system will immediately cut off the charging circuit to stop the battery from continuing to charge, preventing the safety hazards associated with overcharging. The BMS system will continuously monitor the battery voltage and charging status. Protection against over-discharge is also essential. Overdischarging the battery damages the electrode material inside the battery, which will significantly impair its performance and may render it unusable. In order to prevent overdischarge and ensure battery safety, the BMS system will continuously monitor the battery's discharge and promptly cut off the discharge path when the battery voltage falls to the predetermined discharge cut-off value.

(3) Enhancing Efficiency: Unlocking Robots' PotentialBy precisely predicting the remaining battery power and health state, the BMS system's algorithm—which is the most crucial component—provides exact assistance for the power output and task execution of robots. The BMS system's ability to accurately estimate the battery's state of charge (SOC), or remaining power, is crucial. Robots must logically plan their jobs based on the battery's remaining capacity in order to prevent task interruptions from low power. The BMS system will employ sophisticated algorithms to precisely predict the battery's state of charge (SOC) while accounting for a number of variables, including temperature, voltage, current, and other variables. In this manner, the robot is able to organize its activities logically and know its power condition in real time, ensuring that tasks are completed successfully. For instance, in logistics warehouses, logistics robots can prioritize the handling of goods for urgent orders, increase job efficiency, and optimize handling routes based on the battery power information provided by the BMS system. Furthermore, the BMS system allows the sweeping robot to automatically return to the charging station to recharge when its battery is low on power. Once fully recharged, it can resume its sweeping duties with minimal manual intervention. For instance, service robots have relatively small batteries that are used frequently and require frequent recharging. By estimating the battery's state of health (SOH), the robot can anticipate maintenance and replacement needs and comprehend the battery's performance condition in real time. As the battery's performance declines with increased use, the BMS system monitors a number of factors, including internal resistance and capacity, to assess the battery's state of health (SOH). The BMS system will sound an alert in advance to remind the user to inspect or replace the battery when the SOH falls below a certain level. This will prevent the battery's performance from degrading and interfering with the robot's regular operation.

The Evolution of Intelligence, Integration and Efficiency

The future growth of the robotics sector will be significantly impacted by the important aspects that BMS systems are developing around, including intelligence, integration, and efficiency. An key avenue for the development of BMS systems in the future is intelligence. The BMS system will be able to analyze data and make decisions more effectively with the use of artificial intelligence and network connection technology. In order to achieve the intelligence and automation of battery management, it can not only continuously check the battery's condition but also forecast its remaining life and probable failures by learning from and analyzing vast amounts of historical data. It can then take proactive steps to avoid these problems. For instance, the BMS system can use machine learning algorithms to optimize the battery's charging and discharging strategy based on the robot's usage patterns and environmental factors, thereby enhancing the battery's performance and lifespan. Another unavoidable trend in the evolution of BMS systems is integration. More functional modules will be integrated into a single chip in the future BMS system, which will reduce the number of devices, cut system volume and cost, and increase system stability and dependability.  In order to facilitate information sharing and teamwork, as well as to raise the robot's overall performance and intelligence level, the BMS system will simultaneously be intricately integrated with the robot's other control systems, including the motion control system, intelligent decision-making system, etc. Regarding high efficiency, the BMS system will consistently decrease energy loss and increase charging and discharging efficiency. For instance, the robot will be able to charge more quickly and conveniently thanks to new charging technologies like wireless charging and rapid charging, which will also save downtime and increase productivity.

Conclusion

The BMS system is essential to the growth of the robot since it serves as its energy core. It not only ensures the robot will operate safely and steadily, but it also enhances the robot's performance and efficiency, providing a strong basis for the widespread use of robots in a variety of industries.