Concepts · 2011
The birthday car from the future.
For the automobile’s 125th anniversary, Mercedes built an S-Class from roughly 2025: gullwing doors, a hydrogen tank fused into the body, and a thousand kilometers of range.
Frankfurt, September 2011. One hundred and twenty-five years after Carl Benz registered patent number 37435 for his “vehicle with gas-engine drive,” his company unveils a five-meter silver coupé whose name ends in an exclamation mark: F 125!
The banner over the stand read “Legend meets future.” The legend part was easy to spot — those doors. The future part was a claim: that a large, luxurious Mercedes could run entirely without emissions, without feeling like a compromise.
Chapter I
Wings, without pillars.
The gullwing doors were not nostalgia — they were a structural argument. The body mixes carbon-fiber composite, aluminum and high-strength steel into a shell so rigid that the B-pillars could be deleted, with crash-responsive protection built into the huge doors themselves. Mercedes framed it explicitly as Béla Barényi’s rigid-passenger-cell principle of 1952, carried forward.
Each door opens onto a full four-seat luxury cabin — no stooping past a pillar, no rear door needed.
The design, developed under Gorden Wagener, was a long look at the next S-Class generation — the broad upright grille, the full-length sculpted flanks and sweeping roofline surfaced in production Mercedes flagships within a few years.
Inside, a cloud-connected system called @yourCOMAND answered to gestures and natural speech — in 2011, years before voice assistants had names.
Chapter II
A fuel tank you can’t remove.
The F 125! was a hydrogen plug-in hybrid. A fuel cell fed four motors — one per wheel, in a torque-juggling system Mercedes called e4MATIC — with a combined 230 kW. A 10 kWh lithium-sulfur battery, a chemistry that remains experimental to this day, handled the first 50 kilometers alone; hydrogen covered the rest of a claimed 1,000-kilometer total.
The boldest idea hid in the floor. Instead of the usual 700-bar cylinders, the F 125! proposed a structural hydrogen tank — storage fused into the body itself, working at a fraction of the pressure, stealing no space from the cabin. Mercedes labeled it early-stage research and suggested production around 2025.
- System output
- 230 kW
- 0–100 km/h
- 4.9 s
- Total range
- 1,000 km
- Battery
- 10 kWh Li-S
Epilogue
The future that took the other road.
The F 125! bet on hydrogen winning the luxury car; the following decade handed that victory to batteries, and Mercedes eventually moved its fuel-cell work to trucks. Lithium-sulfur cells and structural tanks remain laboratory science. Yet the car’s outline aged perfectly — squint and you see the S-Class Coupé of 2014 — and its central question, how a flagship stays a flagship without a V12, is the one every Mercedes since has had to answer.