customcells® - applications in the automotive industry

The need to decarbonise the transport sector requires a rethink and redesign of the powertrain towards electric propulsion. The announced electric vehicle roadmaps of the OEMs show a large variety of models in the coming years, especially in the area of battery-powered electric vehicles (BEVs). The success of this redesign process, especially the achievement of an electric driving range of more than 500 km, is strongly influenced by the further improvement of the lithium-ion cell towards higher volumetric energy densities (the amount of energy stored per unit volume [Wh L-1]), fast charging capability and cost reduction [€/kWh], taking into account other important performance parameters such as cycle and shelf life, safety and low temperature performance. CUSTOMCELLS® is a game changer in the field of e-mobility. We offer the latest lithium-ion cell technology in the form of prototypes and earlier development phases. Our automotive customers trust us to enable us to have a close relationship with their systems.

In view of the fact that a broad market penetration of BEVs is expected with fully battery-powered electric driving ranges of more than 500 km, the next generation of cells should have volumetric energy densities of at least 750 Wh L-1. Increasing the energy density at the cell level not only leads to greater vehicle ranges, but also has the potential to reduce costs through material savings per kWh. In general, there are three approaches to increasing volumetric energy densities at the cell level.

First, to increase the energy content per volume of the active material of the positive and negative electrodes. In this context, current research and development is focusing on increasing the nickel content of transition metal oxides as positive electrode materials, such as lithium nickel alumina (NCA) or lithium nickel manganese cobalt oxides (NMC), or increasing the operating voltage at cell level by charging these materials to higher limits, thereby extracting more lithium ions from the structure. In the case of NCA electrodes charged to the currently used 4.3 V limits, the amount of extracted lithium is 72%. While the focus of research and development with regard to the negative electrode is on the use of silicon and its derivatives or lithium metal as active materials.

Second, to reduce the amount and volume of inactive materials consumed within the cell, e.g. by coating with ultra-thick electrode mass loads (reduced amount of current collectors), by increasing the content of active materials in the electrode coatings (reduced amount of binder and conductive additive), or by minimizing the thickness of the separator. 

Thirdly, to reduce or compensate the irreversible losses of active lithium ions (from the cathode storage) during the operation of the lithium ion cell, e.g. by optimizing the electrolyte or by prelithizing the negative electrode before mounting the lithium ion cell.

CUSTOMCELLS is a technical development partner along the entire lithium-ion battery value chain as well as a small-series manufacturer of customer-specific lithium-ion pouch cells.