Mercedes-Benz Develops Micro-Converter Tech for Individual Battery Cell Control

Mercedes-Benz is developing a new battery technology that could fundamentally change how electric vehicle high-voltage packs are managed. The company’s new Power Converter, currently in the development stage, aims to control the charge and discharge of individual cells or cell groups rather than treating the entire pack as a single unit.

What Happened

Traditional EV traction batteries monitor individual cells but charge and discharge them uniformly, meaning the whole pack delivers power at the same rate. Mercedes’ new approach uses programmable micro-converters to manage each cell independently. This technology allows for the integration of different cell chemistries and voltages within the same battery pack. Additionally, the system removes the need for bulky centralized power electronics by handling AC and DC conversion, as well as bidirectional charging, directly through the micro-converters.

Why It Matters

For EV owners, this technology could significantly impact battery longevity and repair costs. Currently, when a single cell in a pack fails to sustain voltage, the entire battery often requires replacement. With Mercedes’ approach, a faulty cell can be disabled by its micro-converter, resulting in a slight reduction in capacity but allowing the vehicle to continue operating. The system also enables modular battery usage, where parts of the pack can be put into standby mode for preservation if the owner’s daily driving needs are low, unlocking full capacity only when needed for long trips.

The Bottom Line

While Mercedes-Benz states the technology has the potential to boost driving range and efficiency, it acknowledges a potential reliability concern: the presence of thousands of micro-converters inside the pack increases the number of components that can fail. The company has not announced a timeline for when this technology will appear in production vehicles.