RUB researchers develop an early warning system for vehicle batteries Battery management permanently checks the age, state of charge and operational reliability. A flat battery can turn an unsuspecting car driver into an unintentional pedestrian. The fact that vehicle batteries go flat all of a sudden is a well-known problem, but one that can also be avoided in future.

Scientists from the RUB working group for Energy Systems Technology and Power Mechatronics headed by Professor Dr. Constantinos Sourkounis and Philip Dost have now developed an effective early warning system together with the Isabellenhutte Heusler GmbH and Co. KG.

The new battery management system for lead-acid accumulators is intended to prevent drivers from a total breakdown. The car driver is informed via the on-board computer that a change of battery or a new vehicle battery is imminent. Compared to previous battery management systems, no subsequent reprogramming is required in the garage.

"During the first journey the system automatically measures and recognizes at the same time the current battery parameters", said Professor Sourkounis. Information is provided about the age, the charge and functionality of the vehicle battery.

This intelligent control is urgently required as modern cars require more and more energy. Apart from the combustion motor and headlights, dozens of small electrical motors and sensors need electric power.

New start predictable
"Accumulators with big capacities mean a prolonged service life, but they age as well", explained Professor Sourkounis. High-performance vehicle batteries are also more expensive and also not completely immune to cold and long periods of non-use.

If the life of the battery is not eternal, it is practical to be informed permanently about its current state.

"For the first time it is possible to predict with our battery management system whether a new start will be possible before the motor is turned off - and without the need to adjust difficult to determine parameters such as the diffusion capacity of the battery", said Sourkounis.

Furthermore, an advanced warning function indicates to the driver if the battery needs charging.

Industrial partner from Hesse
Industrial partner of the Bochum researchers is Isabellenhutte Heusler GmbH and Co. KG from Dillenburg in Hesse. The automobile component supplier is the market leader for precision measuring resistors. These so called shunts are important components of the battery management systems. They allow the state of the battery to be measured.