Fiat Adding Bosch Stop-Start System to Fiat 500; Bosch Projects 50% of Euro New Vehicles to Have Stop-Start by 2012
|A specially adapted starter and the engine control unit are the central components of the Bosch stop-start system. Click to enlarge.|
Beginning in March 2009, Fiat will feature a Bosch start/stop system on the Fiat 500. (Earlier post.) Bosch supplies the specially adapted starter, the engine management system, and the battery sensor. Bosch has been manufacturing this start/stop technology since 2007, and has already delivered more than 500,000 starters to BMW and Mini. (Earlier post.)
In the Fiat 500, the system will initially be available in combination with the Dualogic automated manual transmission and a 1.2-liter engine. Fiat plans to install the system in other variants and models as early as 2009.
Bosch also supplies the engine control unit for the Fiat 500, including the software used to analyze all the relevant sensor data and to stop and start the engine. In addition, the battery sensor is also supplied by Bosch. It computes the current state of battery charge and relays this information to the energy management system.
In 2008, roughly five percent of all new vehicles in Europe are equipped with a start/stop system. By 2012, we estimate this will be every second newly registered vehicle—most of them with Bosch technology.—Stefan Asenkerschbaumer, president of the Bosch Starter Motors and Generators division
In the next few months, series production of other cars featuring this Bosch technology is to start—the Kia cee’d, for example.
Test drives by Bosch engineers show that stop-start systems reduce fuel consumption, and thus also CO2 emissions, in the New European Driving Cycle (NEDC) by up to 5%. In the urban component of the NEDC, the saving can be as high as 8%. Stop-start systems automatically stop the engine when the vehicle is stationary, for example at traffic lights. The engine is restarted as soon as the driver depresses the clutch pedal to put the vehicle back into gear. As starter-based systems are largely based on existing components, their cost-benefit ratio is excellent. This approach is also suitable for cold starts in diesel engines.
Bosch has considerably increased the specified number of starts of the start/stop starter and as a consequence increased its service life compared with a conventional starter. Bosch strengthened the bearings subjected to heavy loading in the starter, and further improved the planetary gear. The commutator is optimized for longer life.
Next to the starter, the control software, and a battery sensor, the system as a whole includes a crankshaft sensor and the respective sensors at the pedals. A high efficiency alternator in combination with a deep-cycle resistant battery means that the amount of time the vehicle can remain stationary with the engine switched off is increased.