In automotive design, dual-motor, four-wheel-drive layout is mainly used by battery electric vehicles by having two

electric motor An electric motor is a machine that converts electrical energy into mechanical energy. Most electric motors operate through the interaction between the motor's magnetic field and electric current in a electromagnetic coil, wire winding to gene ...

s that each drives the front and rear axle, creating a four-wheel drive

layout In general terms, a layout is a structured arrangement of items within certain limits, or a plan for such arrangement. Specifically, layout may refer to: * Page layout, the arrangement of visual elements on a page ** Comprehensive layout (comp), ...

. This is made possible by the smaller size of electric motors compared to

internal combustion engine An internal combustion engine (ICE or IC engine) is a heat engine in which the combustion of a fuel occurs with an oxidizer (usually air) in a combustion chamber that is an integral part of the working fluid flow circuit. In an internal comb ...

s (ICEs), which in addition are also accompanied by a bulky engine cooling system, allowing it to be fit more versatilely into multiple locations. The use of separate motors for the front and rear drive wheels eliminates the need of a

drive shaft A drive shaft, driveshaft, driving shaft, tailshaft (Australian English), propeller shaft (prop shaft), or Cardan shaft (after Girolamo Cardano) is a component for transmitting mechanical power (physics), power, torque, and rotation, usually ...

that is ubiquitous in four-wheel drive ICE vehicles, freeing up space for bigger battery modules, which are commonly mounted on the chassis floor between the axles. The dual-motor layout is beneficial in re-distributing torque and power to maximize effective

propulsion Propulsion is the generation of force by any combination of pushing or pulling to modify the translational motion of an object, which is typically a rigid body (or an articulated rigid body) but may also concern a fluid. The term is derived from ...

in response to road grip conditions and weight transfer in the vehicle. For example, during hard acceleration, the front motor must reduce torque and power in order to prevent the front wheels from overspinning as weight transfers to the rear of the vehicle. The excess power is transferred to the rear motor where it can be used immediately. The opposite applies when braking, when the front motor can accept more regenerative braking torque and power. However dual-motor vehicles usually have less range for the same battery size than single-motor designs. In addition, electric vehicles may be equipped with more than two electric motors to achieve greater power output and superior handling. The first mass-produced triple-motor layout was introduced on the Audi e-tron in 2020, which consists of one motor at the front and two motors at the rear. A rare example of a non-electric vehicle utilizing this layout is the Citroën 2CV Sahara, which has two flat-twin petrol engines.

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{{Automobile layouts Car layouts Four-wheel drive layout Electric vehicle technologies

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