Battery plant technology: Cost-efficient battery production

High speed – high precision

What are commonly called batteries in electric or hybrid vehicles are referred to by experts as battery systems or packs. They are made up of battery modules and additional components such as electronics and cooling and protective devices. Battery modules are made up of individual battery cells, which in turn – put simply – are made up of wafer-thin, coated electrode foils, equally thin separator foils and electrolytes. So it’s a broad field, and there are also different cell types such as round, pouch, and prismatic cells.

And it’s a field where progress is urgently needed. Predictions on exactly how the market for hybrid and electric vehicles will develop in the future vary depending on which analysts or research institutes issued them, but automotive OEMs such as Daimler, BMW, and Renault now need batteries in quantities that can no longer be provided by the current production methods – or at least not cost efficiently.

Battery cell production requires extreme precision

Production of the actual battery cell is a major challenge. The mechanical processes involved – coating, cutting, stacking, winding, and packing – may appear simple at first glance, but they need to be automated, fast, and yet also deliver extremely high precision. One example is coating the substrate foils for the electrode material: Graphite is applied to copper for the anode, and lithium oxide to aluminum for the cathode. The foils, themselves only around ten micrometers thick, require an even coating thickness of between 150 and 300 micrometers.

In our own technical center in Hohenstein-Ernstthal in the German state of Saxony, we test all aspects of battery production from cell to complete system. This work forms the basis for the planning and design of production lines.