The passenger vehicle could be considered the largest and most widespread stand-alone technical consumer system requiring an on-board energy supply.  However, the vehicle has no permanent power supply of its own and uses its battery as a buffer for consumption peaks, which have dramatically increased over the years to higher than 3,000 watts.  Therefore, Siemens VDO developed a full product line of Battery and Energy Management (BEM) solutions to help meet vehicles' increased demand for electrical energy - of which its Intelligent Battery Sensor (IBS) innovation will go into series production in 2008 on European passenger vehicle applications.

Avoiding Breakdowns

More than one-third of all vehicle breakdowns in the United States are a result of a form of battery failure.  Across the globe, dead batteries remain the leading reason why vehicles fail to start - which is not surprising, as the battery is the only source powering a vehicle's electricity consumers remaining active when the ignition is off.  Siemens VDO's IBS is an essential element to managing and optimizing the battery's electrical energy resource.  The shunt-based IBS supervises all vehicle modes from key-off to cranking with a high degree of accuracy.  It measures battery current, voltage and temperature for any new or aged lead acid battery.

"Using the information from the battery sensor, our self-adapting Battery Monitoring Algorithm diagnoses the battery in terms of energy content and the ability to provide vehicle functions with power," said Siemens VDO Business Development Manager Ward Randall.

Using a proper Battery Monitoring System (BMS):

• Vehicle breakdowns could be lowered by up to 80 percent due to reduced battery drainage and advising drivers on battery replacement;

• Driver satisfaction can be enhanced through ensured ignition cranking, even after long periods of vehicle rest;

• Battery warranty cost can be reduced through failure mode detection;

• Cost reductions and improved quality can be achieved in production by immediately detecting and replacing defect components;

• Carbon Dioxide (CO2) emissions can be reduced by using reliable battery status; and, information to support engine efficiency solutions, Stop-Start system functions.

Battery & Energy Management's Scalable Approach

The Battery Monitoring System is part of the modular and scalable BEM solutions and serves as a base product for future vehicle energy architectures.  The increase in by-wire solutions and the electrification of safety-relevant functions require fail-safe architectures, including additional energy storage devices and safety function strategies for on-board energy use.  While by-wire functions, like the electronic wedge brake and electric power steering increase safety, efficiency and performance, it is vital for these functions to be available in the event of a possible failure of conventional energy systems.

Another focus point for energy management solutions will be to minimize any noticeable degradation of comfort function performance in the event of a weak power supply.  The system also can help mitigate the risk of destabilizing the onboard electrical system if a driver creates an overload by activating too many comfort and convenience functions.  This is ensured by the Power Trader solution, a feature providing a stepless distribution of energy throughout the vehicle.

In principle, Power Trader is part of a global approach to vehicle energy management and can be employed to optimize every type of vehicle energy system, including hybrid drive solutions. 

Environmentally Sustainable Mobility

The growing consumer concern of increasing fuel prices and pollution is leading to the desire for optimized travel.  Today, Siemens VDO is trying to take up the energy challenge by developing an innovative Eco-Driving solution with the objective to help drivers become active stakeholders in environmentally sustainable mobility.

The Gerico Eco-Driving approach is an on-board ecologically friendly driving assistance system coupled with GPS navigation functionality.  The Eco-Driving assistant system visually and audibly provides the following information to the driver without directly interfering with vehicle operations:

• Optimum speed for each road type.

• Optimum gear ratio according to speed.

• Actual fuel consumption in comparison to optimum use.

• Help and alert messages adapted to individual driving style, traffic conditions and route topography.

The Gerico Eco-Driving solution provides the general public with the technology advantage allowing them to better control their fuel bill, maintain driving enjoyment and respect the environment.  For even greater sustainable mobility, Gerico Eco-Driving will eventually be available in personal vehicles, as well as for professional fleets.

Siemens VDO Automotive is a leading international automotive electronics and mechatr