Strong Together

Battery electric vehicles are well on the way to becoming the primary drive technology in the automotive sector. This increasingly directs the focus on the cost aspects of high-voltage battery production. Quality assurance is tasked with stabilising the complex production process and thus safeguarding the technical requirements of the product. Technological innovations are currently leading to high expenditures for this, making quality one of the key cost levers. Scrap rates of approximately 15 to 30 percent during the ramp-up of production underline the importance of this aspect.¹ For comparison: In the automotive sector, rejects are usually measured in ppm (parts per million). Therefore, industry-leading quality approaches that ensure a stable production ramp-up are crucial to securing a competitive advantage in this highly competitive environment.

Active quality management is a key discipline in cost competition

Industrial battery cell production requires not only a high level of process understanding, it also involves high material costs and considerable energy consumption. At a time when cost pressures are constantly rising due to high raw material prices, growing energy costs and increasing global competition, viable cost-cutting strategies are essential. The traditional levers for reducing costs in the manufacturing industry include economies of scale, energy consumption and technological innovations in addition to personnel and material costs. In cell production, material costs are determined mainly by the choice of electrode material and negotiated supply contracts for the required raw materials. However, the limited room for manoeuvre for the active materials required for the targeted cell chemistry and long-term supply contracts with non-European suppliers make these levers less suitable in the short and medium term. Economies of scale affect all manufacturers equally, for example through the use of automation potential. In view of the difficult starting position of European manufacturers (global market share below 10 %), this lever is also not very promising for the foreseeable future in terms of achieving a cost advantage over the competition.² With a few exceptions, the sharp rise in energy costs in Europe – particularly in Germany – also provides few options for reducing costs. Technological innovations are ruled out as a direct way of reducing costs due to the supposed technological lead in the Far East and the long-term nature of the process. The focus is therefore on factors that can be directly influenced in inline defect detection and preventive quality assurance.

European manufacturers inevitably have to focus on their production quality. And there is enormous potential here: With a conservatively estimated average scrap rate of ten percent and variable costs of 50 euros per kilowatt hour (kWh), scrap costs amount to around five euros per kilowatt hour. In a typical gigafactory with an annual nominal capacity of 35 gigawatt hours (GWh), these costs add up to an impressive 175 million euros. Reducing the scrap rate by 20 percent alone would save 35 million euros. There are also positive effects in the context of long delivery times and material bottlenecks that have not yet been taken into account. This is reason enough to systematically and vigorously improve quality in cell production.

Similar challenges, similar solutions

Cell production basically consists of three main steps: electrode production, cell assembly and cell finalisation. Manufacturers are faced with very similar challenges, as a recent study by Porsche Consulting makes clear: From ensuring a homogeneous mixture of active materials, uniform coating and compaction of the electrode tracks to the gentlest possible handling of the cell components – the fundamental challenges in quality assurance are largely the same.³ Studies have shown that, despite common problems, quality solutions are predominantly worked on individually.⁴ Research initiatives at major universities and applied research institutes address some of these problems at the highest technical level.^1;5 However, there are no signs of any cross-manufacturer efforts to exploit the enormous cost-cutting potential.

The solution of specific quality problems or the technical monitoring of critical parameters represent an integral competitive advantage for cell manufacturers in terms of potential savings and are therefore understandably rarely shared. Due to the uniform nature of the problems, the solution approaches are comparable and transferability is possible in principle. From the monitoring of clearly defined parameters during the mixing of the electrode coating to dynamic pressure regulation during the electrode rolling process: The solution principle is often obvious, but the challenge lies in the technical implementation. Despite their low market power and structural disadvantages, European manufacturers often act as lone warriors instead of jointly tapping the potential regarding the cost of quality. Quality assurance technologies that are already available today signal potential savings of over ten percent with respect to the scrap rate. In view of the total European nominal capacity of 190 gigawatt hours in 2023, this would result in a directly achievable savings potential of an impressive 100 million euros per year under the assumptions described.

Cooperation creates cost benefits

European cell manufacturers currently account for less than ten percent of the global market. Due to geopolitical and economic disadvantages of the location, cost advantages over the competition cannot be achieved with the typical levers. Therefore, only extremely efficient production processes using the knowledge of well-trained specialists and – above all – comprehensive cooperation remain. This would not only significantly reduce production costs, but also cushion expected capacity bottlenecks in cell production in the event of a renewed increase in demand for battery-powered electric vehicles. In addition, there would be savings in required investments of up to 120 million euros per gigawatt hour of annual production capacity.

The next technological innovation in the form of solid-state cells offers a great opportunity. A solid-state cell differs from conventional batteries in that it uses a solid electrolyte instead of a liquid or gel-like electrolyte, resulting in greater safety and energy density. This storage technology is fundamentally changing the manufacturing process. New steps such as pressing the electrodes with the solid electrolyte are added, while other steps such as drying or electrolyte filling are omitted. Most of the rest of the production process also needs to be adapted, with an even greater focus on technical cleanliness. This gives European manufacturers the opportunity to develop effective quality assurance measures through cooperation. The globally unique networking between applied research and industry offers ideal conditions in Germany to outpace the global competition.^1;4;5;6 In this way, industrialisation can be accelerated and cost savings achieved through intelligent quality work.