1982 Plug-In Hybrid Mercedes Wagon
If the BMW i3 had a predecessor, this would be it.
In 1982, Mercedes-Benz wheeled out a REx version of its W123 T (T for Touring) station wagon at the 32nd annual Hanover Trade Fair. Mercedes knew it was on the right track, but technology of the day wouldn't allow for the REx W123 to make it into production.
The M-B REx looked almost identical to the standard W123, with the only noticeable exterior differences being metal vent grates blow the rear windows (to cool the battery pack) and an enlarged fuel filler door (to plug it in).
But under the skin, the REx version of the W123 was incredibly outside the norm.
A 41-hp electric motor was found in the engine bay. That motor sent power to the rear wheels via a 4-speed trans. A rear-mounted nickel-iron hydride battery pack provided the juice and was actually removeable via a wheel and supporting mechanism. Was it battery swap-capable? Sure. You just had to do it manually.
The battery itself tipped the scales at 1,322 pounds and devoured almost the entire cargo space of the W123. It provided only 62 miles of range, but a REx was standard.
A wimpy 2-cylinder engine handled range-extending duties and could provide up to 30 miles of additional range. The tiny engine couldn't power the massive W123, but it could extend range slightly.
But still, the massive and weighty W123 was painfully slow. Top speed was only 50 mph. Acceleration? Nope.
As usual, Mercedes-Benz was ahead of the times.
Today, we see the BMW i3 as "borrowing" and advancing the technology found in the W123. The difference today is that technology has come a long way and weight is no longer an obstacle that can't be overcome. The i3 makes use of extremely lightweight materials (and has the advantage of employing significantly lighter battery technology) to basically duplicate what M-B created 31 years ago.
As for Mercedes-Benz , the REx W123 was only the beginning. M-B followed that up with a several plug-in prototype vehicles, including a pure electric vehicle of the W201 190 in 1990.
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