The launch of the i4 in autumn will give BMW an electric version to rival its 3-Series-based M3 in terms of performance. The top-performing M50 goes 0 to 100 kph (62 mph) in 3.9 seconds, while the standard eDrive40 will manage the same sprint in 5.7 seconds.
The i4 slots in next to the 4-Series Gran Coupe, but weak sales of that model suggest BMW is focusing its attention on the electric alternative, which will be built on the same platform.
The four-door 4 Series had a volume of just 1,214 units in the first half, down 70 percent and well behind the Audi A5 Sportback at 10,714.
C-Class poised to rise
The Mercedes C-Class had a weak first six months of 2021, with sales down 18 percent to put it fourth as the automaker transitioned to a new-generation model.
The new sedan and wagon variants of the C-Class going on sale now will only use four-cylinder engines until the performance AMG version arrives.
The loss of six-cylinder models however will be offset by the arrival of a new plug-in hybrid with a large 25.4 kilowatt-hour battery to give double the electric range of previous models at an estimated 100 km, Mercedes said.
The electric motor has a power output of 129 hp, making it practical for battery-only driving.
"For many of their journeys, our customers will never use the combustion engine," Christian Früh, chief engineer for the C-Class said in an interview published by Mercedes.
The C-Class plug-in hybrid versions of the sedan and wagon will initially be mated with a gasoline engine. A diesel plug-in hybrid will follow.
The Audi A4 was another segment leader that slipped during a period when most models gained compared with the pandemic-hit first half of 2020.
A4 sales dropped 5 percent, a decline JATO attributed to both the car's age and the lack of a plug-in hybrid version in the model line.
The omission hurts models more in this sector than others as drivers seek to avoid higher CO2-based taxes on company cars. "This is a segment strongly affected by fleets," Munoz said.
The current A4 was launched in 2015 and its successor could come as late as 2025, LMC Automotive estimates. The new model will include a plug-in hybrid, LMC predicts.
However, Audi will also launch an electric model in parallel based on the new PPE (premium platform electric), UK's motoring magazine Autocar magazine reported.
Such a strategy would mirror that of the brand's A6 large premium model. Audi plans to launch an electric model badged the A6 e-tron and underpinned by PPE in early 2023, the brand has said.