The recently unveiled battery-electric Mercedes-Benz CLA, based on the German automaker’s new MMA platform, does not support 400V DC fast-charging in several European launch markets.
Without a voltage booster, the third-generation sedan relies exclusively on 800V charging points for electric energy replenishment – a decision that raises questions about its day-to-day usability.
At the root of the issue is the absence of a 400V-to-800V, DC/DC converter in models launched in Germany, Austria and Switzerland. This limits fast charging compatibility to potentially rare – depending on the region – high-power 800V chargers, effectively excluding Europe’s 400V DC charging points, including 50kW public chargers and a large portion of Tesla’s current Supercharger network.
Mercedes-Benz confirms the charging limitation of the CLA in its online configurator with the message: “Please note that charging at 400V charging stations is not possible, and for this reason, they are not shown in the navigation system.”
The restriction does not affect AC charging, so the CLA remains fully compatible with home wall boxes and public AC stations. There, 400V alternating current flows into an onboard charger and is converted into 800V DC for the battery.
DC fast-charging, however, is a different matter. The CLA supports up to a 325-kW maximum charging speed via the CCS standard – a figure that requires an 800V supply. Because CCS cables are limited to 500 amps, 800 volts is necessary to exceed a 200-kW charging speed. Without a DC-to-DC voltage booster, the CLA cannot step 400 volts up to 800 volts and therefore cannot charge at 400V DC stations.
Rival automakers have taken a different approach. Hyundai and Kia equip their electric-powered E-GMP platform models, including the Ioniq 5 and EV6, with internal voltage boosters to enable 400V-to-800V conversion and allow charging from older DC stations. Porsche and Audi use a split-pack battery strategy with their PPE-platform models, such as the second-generation Macan and the new A6, dividing the battery into two 400V sections – charging is then slower, but still possible.
Mercedes has chosen not to implement either solution in CLA models on sale in Europe. A converter is still onboard, but it is only used to supply 12-volt power to auxiliary systems like infotainment and heated seats.
In response to questions from Wards, Mercedes-Benz highlighted the CLA’s WLTP-rated range of up to 492 miles (792 km) for the rear-wheel-drive CLA 250+ sedan variant. However, it declined to explain why the model lacks a DC/DC converter in key launch markets – a feature commonly used by rival brands to ensure broader charging compatibility. For buyers new to electric vehicles, range on paper is only part of the equation; the ability to charge reliably across real-world infrastructure remains a central concern.
While 400V DC fast chargers are being phased out in favor of 800V DC ultra-fast chargers in much of Europe, many are still in operation – particularly in northern European countries like Norway, where public fast-charging infrastructure predates that of southern European countries.
Speculation suggests CLA models destined for the Norwegian market will include the DC/DC booster, though this has yet to be officially confirmed. It also remains unclear whether other European markets will follow suit. As of May 2, Mercedes-Benz’s Belgian and Dutch websites do not mention the 400V charging limitation.
Wards has asked Mercedes-Benz for clarification on the charging hardware specification for electric CLA models destined for the North American market but has yet to receive a response.
