Advanced battery technology for electric driving

Johnson Controls powered advanced battery technology for electric driving is assuming promising dimensions

With its re3 concept car, Johnson Controls has showcasing its innovative battery technology and novel packaging idea for storing energy. 96 lithium-ion cells are uniquely packaged between the front seats in the tunnel console of the vehicle. With more than 7 kWh, the storage module provides sufficient energy to easily transport commuters to and from work or allow families to take an extended shopping trip – without using a single drop of gasoline. Active cooling of the cells ensures optimal operating conditions. The cross-system energy management of the re3 ensures even charging and discharging of the lithium ion accumulators (cell balancing), a key requisite for maximum energy efficiency and the long-term reliability of the storage cells.

Trendsetting packaging concept
Electro-mobility is on the agenda of many nations. Lithium-ion batteries are at the heart of these vehicles and thus of elementary importance for electro-mobility acceptance. However, the huge energy stores often prove to be tricky for many electric and hybrid vehicles.

The feasible energy density, in other words, the ratio of size to capability of an accumulator, forces car designers into making compromises – often at the expense of storage space. The trunk is therefore often used for purposes other than intended or the entire rear seat bench must give way to battery technology.

The designers at Johnson Controls managed to optimally place the energy store in the tunnel console of the re3, making the concept car a true space-saving sensation. The attractive interior design allows ample room for five adults; three of which can sit comfortably in the rear of the vehicle. In addition, the re3 also offers adequate trunk space. But not only is the space of the re3 impressive. The placement of the battery also has a positive impact on driving characteristics. The driver benefits from a low centre of gravity, facilitated by installation of the storage modules in the centre of the vehicle, which enhances ride and handling characteristics.

Johnson Controls-Saft is already manufacturing lithium-ion batteries for series production in Europe. For example, Mercedes uses 35 VL6P lithium-ion cells in its S-Class S400 BlueHybrid, as will the BMW 7 Series ActiveHybrid that will start shipping later this year. Ford also intends to use Johnson Controls-Saft lithium-ion batteries in its PHEV vehicle (plug-in hybrid-electric vehicle). Series production of this model on the North American market is expected to start in 2012.

Great emphasis is placed on the reliability of the electric drives and thus the necessary energy management for use in commercial vehicles. U.S. automaker Azure Dynamics (AZD), who specializes in hybrid-powered commercial vehicles, will equip its next generation of hybrid-electric delivery vehicles with the battery technology of Johnson Controls-Saft starting at the end of 2010. This vehicle class – small delivery vehicles and shuttle buses – represents 12 per cent of total traffic volume and is responsible for 25 per cent of greenhouse gases caused by road traffic in the U.S.