Battery technology is one of the key applications in e-mobility. With CellConnect, the Austrian automotive supplier, Pollmann, has developed a method that makes production of these essential energy storage devices faster, cheaper, and more sustainable. For voltage monitoring between the cells, the cell connector uses new types of plug-in connections made of stamped and overmolded conductor paths. The technology completely therefore avoids welded cable harnesses between the cells. This helps to:

• eliminate cable costs,
• reduce production time,
• reduce required battery space
• and minimize welding quality problems, a feature of every welding process.

With its easy scaleability, the innovative product from Pollmann demonstrates its strengths in highly automated manufacturing processes. The CellConnect method involves plugging instead of welding - and this is done at high speed.

From e-car to hybrid

Pollmann's core competence lies in the plastic overmolding of stamped and bent parts. CellConnect combines experience in handling the complex material connection with automation and industrialization know-how for further processing. The solution was validated in close cooperation with the Fraunhofer Institute. The results of this collaboration with the research institute confirm the performance data of the flexible design. The individual design of the cell connections makes the current-carrying capacity of the connectors easily adaptable to specific applications. Voltages from 48 to 800 volts and more, as well as amperages over 1000 amps, are no problem. This covers the requirements for purely electric vehicles as well as for all hybrid variants.

Sustainable re-use of batteries

The CellConnect plug-in system also brings new flexibility to storage utilization. Battery cells lose storage capacity as the number of charges increases, becoming unsuitable for e-mobility use after a certain service life. With welded cable connections, it is impossible to replace fatigued battery cells. This is easier with the plug-in connections of the CellConnect method, as defective cells are replaced. The serviced battery packs can be reused, for example, in charging stations for electric cars, as well as in home storage solutions.

For technicians: A note on the cell connection technology

• Conductor paths to the cell are isolated.
• Changes in length caused by aging (e.g. through cell expansion), are compensated by the assembly itself.
• Stamped brass voltage and temperature sensing equipment is overmolded with plastic.
• The brass conductor paths are connected by integrated connectors, solder pins, welding, insulation displacement or PressFit.
• High design freedom for any cell arrangement