Strong Together

Battery electric vehicles are well on the way to becoming the primary drive technology in the automotive sector. Based on analyses by Porsche Consulting, the current global annual demand for batteries will rise from its current level of around 1.5 terawatt hours (TWh) to over 7.5 TWh by 2035.¹ This increasingly directs the focus towards 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. Scrap rates of up to 90 percent during the ramp-up phase and exceeding 30 percent at the start of production are not uncommon. Even after several years of production in a steady state, scrap rates still lie between five percent and 12 percent². For comparison: In the automotive sector, scrap is usually measured in ppm (parts per million). Due to the high proportion of material costs in the region of 70 percent³, ensuring production quality is a key cost lever. Therefore, industry-leading quality approaches that ensure a stable production ramp-up are crucial to gain an advantage in this highly competitive environment.

Active quality management is a key discipline in cost competiveness

Industrial battery cell production not only requires a high level of process understanding, it also involves high material costs and significant energy consumption. Since 2020, cell costs have fallen by around 50 percent due to technological advances, economies of scale and improved production efficiency. A typical cell for a battery electric vehicle currently costs around 81 euros per kilowatt hour (kWh), with 70 percent on material costs and 30 percent manufacturing costs.³

In addition to energy and labour costs, the biggest cost driver of production costs is scrap. In a typical gigafactory with a production capacity of 50 gigawatt hours (GWh), the cumulative costs over ten years of operation amount to over 3.75 billion euros.^{3; 4}

For European manufacturers, there is enormous potential for cost savings by systematically improving quality in cell production. Consequently, the focus is on the timely development of quality management systems and on factors that can be directly influenced within inline defect detection and preventive quality assurance.

Cooperation saves costs 

Cell production basically consists of three main steps: electrode production, cell assembly and cell finalisation. These are some of the technical challenges facing manufacturers: From ensuring a homogeneous mixture of active materials, uniform coating and compaction of the electrodes through to the gentlest possible handling of the cell components – the fundamental challenges in quality assurance are largely the same. The production process calls for chemical, mechanical and electrical process expertise whilst maintaining the highest quality standards.⁵ Research has shown that despite shared issues, there is very little collaboration when it comes to quality solutions.⁶ Research initiatives at major universities and applied research institutes address some of these problems at the highest technical level. However, there is no evidence of a European cross-manufacturer initiative to jointly exploit the potential for reducing quality costs.

Solutions for 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. Given the uniform nature of these problems, the potential solutions are definitely 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. 

For newcomers to the market in particular, the key to success can be the exchange of ideas through the formation of alliances and close collaboration with equipment suppliers. The quality label "Machinery made in Europe" and the many years of quality management experience in cooperation with the European automotive industry is precisely what distinguishes this situation from the Asian market. Furthermore, a large number of sub-suppliers for essential system components such as optical measuring devices, in-line metrology for electrodes, control systems and factory software are market leaders in their field originating from Europe and North America. They also act as suppliers for Asian equipment manufacturers and have gained valuable experience with leading cell manufacturers. By realising these synergies, there is potential to gradually close the gap between newcomers and market leaders - market leaders, for example, have scrap costs of seven euros/kWh of produced cell, whilst newcomers spend ten euros/kWh of produced cell on scrap.⁴ 

Market potential of solid-state battery cells

The next technological innovation in the form of solid-state battery cells offers a great opportunity. A solid-state battery cell achieves a higher energy density by using alternative materials with a high storage capacity, such as silicon or lithium metal. The use of a solid electrolyte enables the safe use of these material combinations. This storage technology could fundamentally transform the manufacturing process. Around 40 percent of current production systems and processes can also be utilised to manufacture solid-state batteries. There are also new steps such as electrode pressing with the solid electrolyte, whilst other steps such electrolyte filling are omitted. However, solid electrolytes require a larger proportion of the process steps to be conducted in a controlled atmosphere, taking into account technical cleanliness.^{7; 8}

The share of European cell manufacturers in the global market is currently less than three percent.⁹ However, the race for the industrialisation of solid-state cells between Asia and the West is not over yet and offers the opportunity for new market shares. The tight networking of start-ups, established suppliers and applied research in Europe - and especially in Germany - offers ideal conditions for the local industrialisation of solid-state cells with intelligent quality work.