Concept: modular EV-hybrid features battery and engine swapping

A diagram of the powertrain components of the proposed hyMod. The front-wheel drive traction motor (blue) and in-floor 5 kWh battery pack (green) are always present. The car can change between a rear engine-pack (red) and a larger battery-pack (green) to enable hybrid or full EV operation. Click to enlarge.

A Romanian team—Dan Scarlat (automotive journalist), Marian Cilibeanu (designer) and Cristian Ionescu (engineer)—are proposing the SCI hyMod modular concept car. For clean daily operation, hyMod is exclusively a battery-electric car. For longer-range interurban travels, it can transform into a hybrid car with the assistance of a special change center (“hyMod STATION”).

A synchronous permanent magnet electric 42 kW motor with 200 N·m torque drives the front wheels of the vehicle. In the middle section, beneath the floor, is mounted a 5 kWh battery pack which can be used in both electric and hybrid modes. The rear features a modular structure designed to enable the transformation; the drive shafts and the intermittent mechanical couplings which are used in conventional engine mode are mounted in the area of the rear axle.

Rendering of a hyMod car. Click to enlarge.

Two modules are proposed: one that includes batteries, called “battery-pack” and the second one that includes an engine and transmission, called “engine-pack”. The modules are fastened to the car by means of two bars using special supports mounted on the chassis. To restrict longitudinal movement there are two hooks actuated by the extracting device.

The extractor device at the hyMod stations handles is endowed with sensors and the module has laser emitters. In that way, the alignment of the extraction bars with the corresponding supports on the module is made automatically, the device being capable to move in sides and up/down.

A critical element is the coupling of the mechanical transmission of the engine-pack—especially because the whole engine-transmission pack is fastened to the module frame by means of elastic bumpers. To make possible the coupling of the transmission, booth semi couplings (from the module and from the car) are fixed rigid to the module frame and respective to the car chassis.

This implies the usage of four planetary drive shafts, two between the differential and the intermittent couplings and two from intermittent coupling to the wheels. Because of the fact that engine and transmission movements on the elastic buffers are small, the planetary drive shafts between the differential and intermittent couplings can be short.

The battery-pack option includes a 17 kWh pack which enables a range of 140 km (87 miles); supplemented by the 5 kWh battery in the car, this brings total range to about 180 km (112 miles).

The engine-pack contains a combustion engine which produces 82 hp and is connected to a continuously variable transmission (CVT). Full hybrid system output (front motor and rear engine) is 150 hp. Fuel consumption is less than 6 l/100 km (39 mpg US) and the range surpasses 600 km (373 miles).

The engine module also contains all the other related components, including the fuel tank, the cooling system and the radiator, except the battery, whose function is taken by the car’s battery.

The SCI hy:Mod team estimates the base price of the vehicles without modules (and without tax) to be €25,500 (US$32,848).

Source: Green Car Congress