Last week, Mercedes-Benz showed off what to expect from its next-generation compact luxury cars' interiors. Upon closer inspection, the photos also revealed an A-Class plug-in hybrid is forthcoming.

Virtuel Car first noticed the small detail and published the images on Tuesday. Looking closely at the interior teaser image's all-digital gauge cluster reveals a battery icon and a range readout just below it. Comparing it to the E350e plug-in hybrid, the gauge is basically identical. The display reads 36 kilometers (22 miles) of range remaining with about 75 percent of the battery's power remaining. Some quick math pegs a full charge to last 50 kilometers (31 miles).

Interior design of next-generation Mercedes-Benz compact cars

Interior design of next-generation Mercedes-Benz compact cars

We know the new interior design, which is vastly improved over the current compact cars, will first show up in the next A-Class. Specifically, the A-Class hatchback will receive the luxurious cockpit first, though it won't be sold in the United States. Spy shots already revealed the compact hatchback ahead of its debut in pre-production form. An A-Class sedan, which the brand will sell in the U.S. as a roomier but possibly less sporty alternative to the CLA, will arrive shortly thereafter and boast the markedly improved design. The next-generation CLA and GLA will see the same treatment. The brand promised greater outward visibility in the next A-Class as well thanks to slimmer roof pillars.

2018 Mercedes-Benz A-Class hatchback spy shots - Image via S. Baldauf/SB-Medien

2018 Mercedes-Benz A-Class hatchback spy shots - Image via S. Baldauf/SB-Medien

Mercedes-Benz has gone all-in on electrification for its future cars. By 2022, the German luxury marque's entire portfolio will feature some sort of electrification. Whether 48-volt mild-hybrid systems or more complex electric powertrains find their way into future Mercedes cars is unknown. We do know the brand's "EQ" nomenclature will denote purely battery-electric cars. The first will be the EQC electric SUV.