How innovative contact technology for shunt resistors is setting new standards for battery management systems
How innovative contact technology for shunt resistors is setting new standards for battery management systems
As the need for efficient and dependable battery systems continues to rise, innovative contact technology for shunt resistors is setting new standards in precision and adaptability for Battery Management Systems (BMS) across electric mobility and related fields.
THE GROWING ROLE OF BMS
BMS are pivotal to the success of modern electrification efforts. Whether in electric vehicles (EVs) or renewable energy storage solutions, BMS are responsible for safeguarding battery performance by tracking their state of charge (SOC) and state of health (SOH). At the heart of these systems is the shunt resistor, a key element in measuring electric currents. However, the traditional process of connecting shunts to printed circuit boards (PCBs) has notable limitations that hinder both performance and production efficiency.
Emerging contact technology promises to overcome these obstacles by enabling more precise measurements and optimising manufacturing workflows. This breakthrough is redefining how shunts integrate into BMS, offering substantial benefits for both established and new applications.
CHALLENGES IN TRADITIONAL SHUNT CONNECTIONS
The standard method for shunts involves reflow soldering to connect copper terminals to PCBs. While widely adopted, this approach has significant drawbacks. For one, copper’s high Temperature Coefficient of Resistance (TCR) causes its resistance to fluctuate considerably with temperature changes. When exposed to high currents or external heat, the placement of the soldered connections on the copper terminals can produce measurement inaccuracies within the BMS. Additionally, shunts are often large components, complicating the soldering process and making it time-intensive and resource-heavy. This not only reduces production efficiency but also limits opportunities for in-process quality inspections, increasing the likelihood of defects. These factors underscore the need for a more reliable and efficient solution that enhances accuracy and simplifies production.
CONTACT TECHNOLOGY BREAKTHROUGH
The introduction of advanced contact technology eliminates the reliance on soldering by employing specially engineered contact elements that weld the shunt directly to the PCB. This innovation delivers multiple benefits. By bypassing copper terminals in the measuring section with a direct connection to the copper-manganese resistance element, the technology minimises the impact of temperature-dependent resistance changes, ensuring consistent and accurate current measurements across a wide range of temperatures. Furthermore, welding the shunt directly to the PCB reduces both production times and material waste while enabling improved quality control during assembly. In addition, the welded connections exhibit greater resistance to mechanical stress and thermal cycling, bolstering the overall reliability of the BMS
MAXIMISING BATTERY PERFORMANCE
The contact technology’s ability to enhance battery performance is among its most impactful benefits. Accurate current measurement is fundamental for optimising SOC and SOH calculations, directly influencing the efficiency and lifespan of battery packs. By minimising measurement errors caused by TCR variations, this advancement allows manufacturers to maximise the usable capacity of batteries—a crucial advantage in high-demand applications such as EVs.
FLEXIBLE AND RELIABLE PROCESSES
Traditional shunt resistors often impose challenges in soldering workflows due to their substantial mass, resulting in poor cycle times and higher costs. The welding-based approach resolves these inefficiencies while offering greater design flexibility for BMS manufacturers. Engineers now have more freedom to create compact and versatile battery systems without the constraints of conventional connection methods. Additionally, the enhanced reliability of welded connections improves overall product safety, significantly reducing the risk of failure in critical applications like electric vehicles and grid storage systems.
A STEP FORWARD
With electrification expanding across industries, the demand for precise, efficient, and dependable battery systems is more critical than ever. This new contact technology addresses long-standing challenges in shunt connections while unlocking novel possibilities for BMS design and performance.
By enabling more accurate measurements and streamlining production processes, this innovation holds the potential to become a cornerstone in the future of energy storage and electric mobility. It represents an exciting leap forward and highlights the essential role of ongoing technological development in advancing a more sustainable world.
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