Batteries put pressure on design teams, as they need to consider a range of priorities, including price, reliability, and safety. When handling EV systems delivering between 48 to 800 volts, you can’t risk anything.

A battery system expected to deliver more than a hundred kilowatts of energy with the push of a pedal must operate at hundreds of volts to be efficient. However, lithium battery cells supply only a few volts. To extract enough power, a large number of battery cells are connected together in series as one long stack. A typical electrical vehicle may employ 100 individual battery cells, delivering 350 volts at the top of the stack. And that presents some challenges.

If one cell dies in your long stack of battery cells, you effectively lose all of them. So, you need to monitor and manage all of them—charging them, discharging them—every day for the life of the vehicle. Lithium battery cells cannot be operated to the full extent of their charge and discharge range. They must be kept in a very specific range, such as 15% to 85%, or the cells are weakened.

The benefits of working closely with ADI’s battery management system experts go beyond having access to a broad portfolio of components and products. They offer OEMs access to our system-level expertise, deep domain knowledge, and years of practical BMS design experience. OEMs can obtain high efficiencies in miles per charge, extend battery lifetimes, ensure safety, and increase brand confidence.

Patrick Morgan, Vice President, Automotive at Analog Devices said, “Customers tell us they need confidence when using our products. So, we stage a technical summit at their site or our factory and bring in our key designers and application engineers to meet their team. We spend a day or two going through our roadmap, issues they need to solve, and then discuss how we would approach their specific problem. We build trust by focusing on collaboration.”

Founded in a garage in Croatia by a 21-year-old inventor less than 10 years ago, Rimac Automobili grew into a 600 employee technology powerhouse. Today, Rimac designs, develops and manufactures electric hypercars and high-performance electrification systems for global automotive companies.

ADI’s precision BMS integrated circuits (ICs) enable Rimac’s EVs to extract maximum energy and capacity out of its batteries by delivering highly accurate battery cell measurement. Sophisticated diagnostics enable the system to monitor cell characteristics, voltage, and temperature and to determine charge state at any given time. “Precision accuracy directly translates to maximizing battery capacity and range with fast charging time,” said Patrick Morgan.

“Rimac is a technology powerhouse in the field of high-performance electric vehicles. We develop and manufacture key electrification systems for many global automotive companies and raise the bar for performance EVs with our own hypercars,” said Rimac’s CEO Mate Rimac. “Our application of battery management systems are among the most demanding in the world, requiring the highest accuracy, massive current and voltage draws over very short time scales, and rapid dynamic adjustment within the battery management control system. We have decided to adopt the Analog Devices portfolio of battery management ICs across our complete product line. We have benchmarked these ICs in the market and selected Analog Devices for superior precision measurement accuracy and product robustness over the lifetime of the vehicle.”

Working with OEMs, ADI’s architectural innovations will improve the way power density, accuracy, and weight challenges are solved and communicated in the future. We continue to innovate, and our 5th generation BMS is on track for vehicle production next year.