Powering the Present and Future with Battery Management Systems

Globally, as the demand for batteries soars to unprecedented heights, the need for a comprehensive and sophisticated battery management system (BMS) has become paramount. As a plethora of emerging sectors such as electric mobility, renewable energy, and smart microgrids grow in prominence, optimizing the performance of Li-ion Batteries can be a massive gamechanger.

For modern battery manufacturers, the safety and reliability of battery systems are integral to lasting success. A battery management system can serve as the essential component that enables companies to monitor, manage, and control every aspect of their Li-ion battery packs, including the voltage, current, state of charge (SoC), and state of health (SoH). Let’s dive into the importance of embracing battery management systems, the technologies behind smart battery management system solutions, and the myriad of advantages that Bosch’s comprehensive battery management systems provide to help manufacturers stay ahead of their competitors.

A battery management system for Li-ion battery solutions is an essential and comprehensive technology suite designed specifically for monitoring, controlling, and optimizing the performance of Li-ion batteries. This sophisticated system encompasses both hardware and software components, creating a harmonious blend of technologies to ensure the safe, efficient, and reliable operation of Li-ion battery packs.

Let’s take a look at some of the most critical uses of a battery management system for Li-ion battery packs:

• Cell Monitoring: One of the fundamental uses of a battery management system is that it allows complete monitoring of the voltage, current, temperature, and sometimes other parameters of individual battery cells within a pack. By carefully monitoring these parameters, organizations can gain insights into the state of health and state of charge of each cell.
• Enhanced Safety: Modern battery technologies, such as lithium-ion batteries, can be susceptible to safety risks if not managed properly. These safety risks can include thermal run-away due to improper heat evacuation, chemical spillage due to physical damage, electric overload due to excessive electrical current, and much more. With the help of a state-of-the-art battery management system, manufacturers can continuously monitor parameters such as voltage, current, and temperature to ensure batteries operate within safe limits.
• Highly Optimized Performance: Battery management system solutions provide highly accurate monitoring of SoC and SoH parameters, allowing manufacturers to optimize charging and discharging profiles based on real-time battery conditions.
• Improved Battery Life: The longevity of a battery is essential to the performance and cost-effectiveness of a manufacturing company. By ensuring batteries are operated within their safety limits and by preventing deep discharging or overcharging, a battery management system can extend the life of a battery.

A sophisticated battery management system needs to consist of a number of individual components that work in unison. Bosch takes it a step further and ensures the most comprehensive battery management system available, encompassing a myriad of exceptional design and development services.

• Smart and Connected BMS: In order to create a truly smart battery management system, Bosch utilizes a number of IoT solutions. This is achieved through the enablement of BLE, GSM, Wi-Fi, and GPRS. Similarly, Bosch also emphasizes on the development of smart solutions for battery management such as mobile and web applications and cloud solutions.
• Solution Architecting: A crucial part of designing the ideal battery management system is the development of the solution architecture. Bosch specializes in centralized vs. distributed architectures, master-slave configurations, and isolated vs. non-isolated solutions and proposes suitable architecture based on the end use of the battery.
• Electronics HW Design: Electronics hardware design of BMS involves the design and development of various Electronic Control Units (ECUs) based on the architecture. The design is complex with sections in Analog, Digital, and Power Electronics and integration of components like SSR, relays, contactors, hall sensors, temperature sensors etc. to monitor current, voltage, and temperature, as well as control the charging and discharging.
• Embedded Software: The software components for battery management systems include BSW, complex drivers, ASW, functional safety SW, sophisticated battery algorithms to enable precise measurements and predictions of parameters such as SoC and SoH, and much more.
• CoE Functional Safety: A prominent component of Bosch’s battery management system development services is the functional safety analysis. This includes SIL/ASIL classification using the HARA method and support for safety analysis with FTA, FMEA, FMEDA, and Safety V&V.
• Security SW: To achieve exceptional security, Bosch performs software development and concept design for secure communications, secure flash, secure BL, development of cryptography algorithms, secure key management, penetration testing, and much more.
• Wireless BMS: Wireless BMSs which come with several advantages, including reduced weight for greater energy efficiency, continuous monitoring of battery packs for SoH (State of Health) and SoC (State of Charge) for safe and reliable operations, and reduced end-use repair costs by eliminating the physical wiring harness and cables.
• Active Balancing: Active balancing is a sophisticated technique which dynamically redistributes charge between battery cells during charge and discharge cycles. This boosts system run time, increases usable charge in the battery stack, reduces charge time compared to passive balancing, and minimizes heat generation during the process.

All of these components work in unison to provide the ideal experience surrounding the use of battery management systems. Not just the physical components, but even the surrounding systems and features all play an integral role.

For any industry that uses Li-ion batteries, sophisticated battery management systems are absolutely essential. As the market for EVs continues to grow exponentially, modern battery management systems can be used across passenger cars, utility vehicles, AI-piloted vehicles, trucks, and supercars. Similarly, in the industrial sector, machines such as electric forklifts are growing in prominence due to their low noise emissions, allowing them to operate effectively even during the night. Hence, forklifts, garbage compressors, lifts, cranes, electric street sweepers, and even robots can benefit from battery management systems.

Looking even further, in the marine and defense industries, as modern digitized technologies enter the fray, battery management systems can be used for battery packs in submarines, marine battery packs, and defense systems. Similarly, in the energy storage and renewable energy sectors, battery management systems can be used to increase the safety and performance of large grid systems.

The principal function of a battery management system is the monitoring of a variety of battery parameters. These parameters provide valuable insights into the state of the battery, ensuring safe and efficient operation. Some of the critical parameters that battery management systems measure are seen here:

• Cell Voltage: Monitoring the voltage of individual battery cells or modules is essential to ensure balanced charging and discharging. Battery management systems measure cell voltage to detect any imbalances that could lead to overcharging or over-discharging of specific cells, which can degrade battery performance and compromise safety.
• Current: By continuously monitoring the current, the battery management system can determine the amount of charge entering or leaving the battery at any given time, enabling accurate SoC and SoH estimations.
• Temperature: In order to ensure exceptional performance and safety, battery management systems utilize temperature sensors strategically placed within the battery pack to measure and track temperature variations. If the temperature exceeds the safe limits of operation, the system triggers protective measures like reducing the charging or discharging rate to prevent overheating and potential thermal runaway.
• Internal Resistance: Battery management systems monitor the internal resistance of the battery, which indicates its ability to deliver power efficiently. Increased internal resistance can lead to energy losses, premature degradation, reduced performance, and heat generation within the battery.

By carefully monitoring and smartly analyzing these parameters, battery management systems can enable highly accurate predictions of SoC and SoH. These parameters allow organizations to get deeper insights into the capabilities and capacities of their existing batteries. The SoC is generally calculated by analyzing voltage, current, and temperature data. Whereas the SoH predictions are made by considering factors such as cycle count, internal resistance, capacity degradation, and other degradation mechanisms.

Another prominent function of a battery management system is enabling communication between components using protocols. Within the battery management system, internal communication is generally enabled using CAN protocol. This allows reliable and robust communication between different components of the system, ensuring seamless coordination and exchange of data. Similarly, external communications are often enabled using protocols such as CAN, Modbus, or Ethernet. This allows effective integration with other components of the overall system or external monitoring devices.

• Embedded system battery algorithms for SoC, SoH, capacity prediction, and much more achieve accuracy of up to 98%.
• Embedded firmware with layered architecture, state-of-the-art applications, error detection and event handling, and model-based development.
• Battery management systems can measure voltage with an accuracy of +/- 2 mV, battery level voltage with +/- 100 mV, current with +/- 50 mA, and temperature with +/- 1°C.
• IP67 qualification.
• Design compliance to UL/IEC 60730, SIL levels, Class A/B/C.
• Verification and validation include automated test cases, simulation of battery packs, behavior testing up to 90%, and field analysis and support.
• Battery management system has a capability to achieve less than 200 µA sleep current.
• Bosch is working on active balancing, wireless BMS and continuously upgrading to future technologies thus giving customers edge in the market.

As battery technologies continue to advance and the demand continues to grow, battery management systems hold incredible promise. The emergence of modern innovations such as AI, IoT, and cloud capabilities in this domain further strengthens the position of battery management systems.

Moreover, as extending battery life, improving sustainability, enhancing safety, and driving efficiency take center stage, it’s undeniable that battery management system solutions will play an integral role in creating a greener economy. The future of battery management system solutions holds incredible potential, empowering battery manufacturers to reach unprecedented heights and create a truly battery-charged tomorrow.