Long live the battery!

    Covering the distance with Marquardt: an innovative system is jump-starting electric motors

    The battery is the heart of the electric car – and an Achilles’ heel at the same time. After all, what good is the most powerful lithium-ion battery if it fails or is even damaged due to heat, cold or high loading? For many car buyers, the fear surrounding limited range is the main argument against buying an electric vehicle. But if you want to convince customers, you have to provide answers. Just like Marquardt: the company has developed a key technology for e-mobility with its new battery management systems.

    Electromobility is one of the major topics of the future, and this is a development being driven by climate protection goals and political guidelines for car manufacturers. Fines will be imposed from 2021 if EU targets for corporate CO2 emissions are exceeded. The German Federal Government is striving to see one million electric cars on Germany’s roads by 2021. Reality still doesn’t come close to that, as illustrated by the current McKinsey Electric Vehicle Index (EVI 2018). The management consultancy firm regularly examines the development of e-mobility in the fifteen most important industrialized countries. According to the study, 58,000 new electric cars were registered in Germany in 2017 – twice as many as in the previous year.

    The dimensions on the Asian market are very different, especially in China. With an increase of more than 70 percent and over 600,000 electric cars sold in 2017, almost every second electric car in the world was put on the road in the Middle Kingdom. In production, too, the Chinese have left their competitors trailing on the market, as they hold a 41 percent share of the global market, followed by Japan (19 percent) and Germany (18 percent). Worldwide, new registrations have exceeded the million mark for the first time ever, with 1.2 million vehicles being registered. While this is still only a small step, these are figures that have shaped the buzzword “e-mobility megatrend”.

    Thanks to a clear focus, we are now the specialist for the battery management system, and we will continue to expand this position with innovative solutions.

    Wolfgang Häussler Product Manager Innovations

    The fight for market shares started a good while back now. The demand for new technologies that eliminate previous weaknesses is correspondingly high, especially for batteries – with the key phrase in this regard being “fear of limited range”. Wolfgang Häussler, who is Product Manager for Marquardt Innovations, has felt the surge in demand in his daily work: “We can barely handle all the inquiries. Within a very short space of time, sales of our battery management systems have increased exponentially.” This system improves battery life significantly, not only in cars, but also in boats, motor homes, power tools and gardening equipment too.

    The fact that Marquardt has become such a sought-after partner in the battery sector wasn’t an automatism initially. Around ten years ago, Mr. Häussler explains, people were thinking about what they could do about e-mobility. The clear feedback from many automotive customers was ‘We urgently need a supplier that builds systems that have the reliability and safety we’ve come to know from your drive authorization systems.’ He continues: “This was the starting signal for us, because it’s exactly what our expertise is all about: safe electronics, solid switching components and intelligent modules that communicate reliably within a vehicle.” A new business segment was born.

    But, while it might sound simple, it’s actually far more complicated. The trend towards e-mobility has only been made possible by the performance of lithium-ion batteries. And there’s just one catch: they react sensitively to deep discharge, overcharging and temperature peaks. So ongoing battery observation is necessary. Marquardt has developed a battery management system (BMS) that continuously analyzes the battery condition. Is there condensation in the battery holder? Is there a risk of overheating? How high is the filling level and how far does the vehicle travel on what route?

    Smart driving systems combine the BMS’ reliable statements with the navigation device’s data. Are there mountains to climb? Is the route twisty? Or is there a risk of traffic jams, which could affect the energy demand? The BMS uses on-board diagnostics (OBD) to identify errors and reports the “findings” to the vehicle’s control unit. Marquardt is therefore also laying the foundations for connected monitoring, in which the data is sent directly to the workshop.

    The BMS is based on three components.
    A sensor system is always “listening” to the battery. It measures the voltage, the temperature, the currents and the direction they’re flowing in within the cells. The system’s “brain” is the control unit, which receives all the measured data, uses it to calculate the most important information and gives instructions on what to do: charge, cool down or balance. The latter is one of the system’s key tasks. After all, batteries are made up of hundreds of cells that work collectively. They cannot be discharged and charged individually – only together. However, it is possible for one cell to charge itself to 100 percent, while its neighbor only charges itself to 95 percent. In this situation, what is known as “balancing” is necessary. The BMS monitors each individual cell to achieve a permanently optimized operating condition, making the battery last much longer.

    Last but not least, the system’s “muscles” are the switching unit, which distributes and fuses the energy to the various consumers via copper rails. This distribution box is also responsible for switching off the battery in an emergency. After all, a car battery can have 400 volts, or trucks even up to 800 volts. The greater a battery’s power density, the higher its performance, but the greater the potential dangers. This increases the risk of fire and explosion if an accident occurs. It also makes it all the more essential for the safety precautions to work faultlessly.

    In 2015, the first BMS from Rietheim went into series production within various premium segment vehicle manufacturers. Orders have been rising steadily since then. Wolfgang Häussler sees Marquardt’s strategic focus as a strength, just like he does its many years of experience: “Many market participants offer a ‘general store’ in the e-mobility sector. Thanks to a clear focus, we are now the specialist for the BMS, and we will continue to expand this position with innovative solutions.” Pre-development projects for the next technological level are already in the works. In the meantime, many customers would like Marquardt to also build complete batteries and not just supply the electronics. In perspective, this is quite possible and demand beyond the automotive industry is huge. Indeed, more and more appliances are being powered by rechargeable batteries – from e-scooters to leaf blowers, motorboats and cleaning equipment to exoskeletons.

    „A uniform standard that applies to all batteries and BMSs would be a real breakthrough to advance other industries.“
    Wolfgang Haeussler, Product Manager Innovations

    So a uniform standard that applies to all batteries and BMSs is necessary. The German Association for Electrical, Electronic & Information Technologies (VDE) has recognized this and set up a standards committee that Marquardt is also involved in. Product Manager Mr. Häussler believes that standardization harbors great potential: “That would be a real breakthrough to advance other industries.” Wherever the journey in the electric age takes you – Marquardt has already set off.

    Contact

    Marquardt GmbH
    Schloss-Straße 16
    78604 Rietheim-Weilheim
    Germany