A traction battery (shown above) is an electrochemical battery which is designed to power an electric drivetrain in an electric or hybrid vehicle.

Traction batteries usually use nickel metal hydride (NiMH) or lithium ion (Li-ion) technology. The next generation of traction batteries will use lithium-sulphur (Li-S) technology.

Because of the large size and heavy weight of traction batteries, they are usually mounted low down in the vehicle in the centre tunnel or behind the rear seats.

The term traction battery is used to avoid confusion with the the much smaller and lower-voltage lead acid battery used to power electrical ancillaries and to start the engine of a hybrid vehicle.

T-tray on Lewis Hamilton's 2011 McLaren

In F1 the T-tray is the front part of the floor of the car, under the driver's legs. It forms a splitter and is one of the most important aerodynamic parts of the car, as it affects the air flow under the car and around the sidepods.

Because it runs close to the ground at the front of the car, the T-tray is susceptible to damage from debris or kerb impact. It is usually designed as a replaceable component so that damage can be easily repaired.

Tiptronic is a Porsche trademark for an automatic transmission with manual override, which has become a generic name for any similar transmission.

The Tiptronic system uses a conventional automatic gearbox with torque converter and adds manual control using a secondary gear selection gate with + and - positions which shift up or down.


A tachograph is a device used in commercial vehicles which measures time, speed and distance.

Tachographs are used to keep track of drivers' working hours, which are legally restricted.

Analogue tachographs record information on paper disks, but since 2006 new vehicles have been fitted with digital tachographs which record information onto a flash memory card.

Not to be confused with tachometer.

TAP Temporary Auto Pilot (Volkswagen)

TCA Track control arm

TCS Traction Control System

TDC Top dead centre