Battery Cell Traceability: The Foundation for Sustainability, Quality, and the Battery Pass

To ensure sustainable and low-emission battery cell manufacturing, it is essential to analyze energy and material consumption as well as the associated greenhouse gas emissions.  

Digital technologies provide the necessary foundation for this. According to a 2024 study by the Fraunhofer Institute for Battery Cell Research and Production (FFB) and Accenture, digital solutions could save a lithium-ion battery cell factory, which produces the most commonly used battery types, with an annual capacity of 40 GWh approximately 27 million euros and reduce its emissions by nearly 10%. [2]

Digital twins, in particular, offer great potential for transparently mapping complex interrelationships within battery cell manufacturing. A digital twin is the virtual representation of a physical object, process, or system. It enables the consolidation of relevant data from various sources and different points in the production cycle. By collecting aggregated production, quality, and operational data at a single access point, a database is created for analysis, optimization, and informed decision-making. In doing so, digital twins access existing IT systems, which handle tasks such as data collection, production-related functions, interfaces, and other responsibilities depending on the specific area.

The digital twin represents the image of real products, their states, properties, and the behavior of their physical counterparts. [3] Holistic data collection across the entire product lifecycle enables a comprehensive analysis of the product. By intelligently linking the product data from the digital master with operational, status, and process data from the digital shadow, causal relationships across multiple process steps can be identified and optimized.

In addition to the product twin, building and plant twins are also crucial for efficient battery cell manufacturing. Through data-driven optimization of the energy efficiency of production facilities, resource consumption can be minimized, and electricity costs, rejection rates, and emissions can be reduced. Product twins, on the other hand, provide insights into resource wear and battery degradation mechanisms, as well as second-life potential, which can be analyzed more efficiently and tracked more precisely based on the recorded data.

Thus, the end-to-end digitization of the value chain is a key enabler for more sustainable battery cell production. 

In the context of digitalization, the topic of traceability is becoming increasingly important. But what does the term actually mean?

Traceability refers to the seamless tracking of material, process, and quality data throughout the entire value chain. This is not only a key component of quality management but also the basis for regulatory requirements in the European Union. Using this traceability, data from all phases of the battery life cycle can be collected and fed back into the relevant phase of the cycle to optimize it. This allows for the targeted selection of suppliers and resource-efficient materials, and enables production and design processes to be made more efficient and sustainable. Ultimately, this process optimization can increase the longevity of the batteries. Traceability thus contributes to resource efficiency as well as to quality assurance and the goal of a circular economy. [4]

The growing importance of transparency and traceability is also reflected in regulatory requirements. This is also the focus of the Battery Regulation, which was developed as part of the “European Green Deal.” A central component of its implementation is the Battery Passport. This is a standardized, digital product file that makes every battery uniquely identifiable throughout its entire life cycle. The digital product twin will take effect on February 18, 2027, and applies in the EU to all batteries in light-duty vehicles, industrial batteries with a capacity of more than 2 kWh, and batteries for electric vehicles placed on the EU market. 

The mandatory information in the Battery Passport includes approximately 90 data attributes across a total of seven categories: 

• General information about the battery and the manufacturer
• Carbon footprint
• Materials and composition
• Performance and durability
• Conformity, labeling, and certifications
• Due diligence in the supply chain
• Circular economy and resource efficiency

The goal is to promote a transparent and sustainable battery value chain and to ensure interoperability and safety. [5]

Thanks to these advantages, the Battery Pass can create significant added value for manufacturers, operators, recyclers, customers, runners, and policymakers throughout the entire value chain. [6]

The responsibility for careful and comprehensive data collection and storage is carried out within a decentralized system and rests with the respective economic actors who place the battery on the market (typically the manufacturer or importer). Actors throughout the battery’s life cycle exchange their respective data based on this system. They gain access via a data carrier, such as a QR code, on the battery. The various stakeholders—such as customers, the public, and the European Commission—are granted different levels of access to the stored information. 

The requirements of the EU Battery Regulation and the introduction of the Battery Passport necessitate extensive organizational and procedural adjustments, such as changes to companies’ IT systems, data management, and infrastructure. [7] In the future, companies must ensure that relevant product, process, and material data are recorded in a complete and detailed manner. Simply recording data at the batch level is often insufficient, as it groups together multiple materials or products that were manufactured under the same conditions. If a problem arises, for example, the production batch of electrode strips from the same coating campaign would need to be inspected or held. 

Data collection at the sheet level, on the other hand, enables a more precise root cause analysis when problems arise, as well as lower rejection rates and, if necessary, targeted recalls. Each sheet can have its own ID, allowing for precise traceability of every electrode sheet throughout the process. 

In terms of transparency, integrating information from upstream supply chains is particularly challenging. To meet requirements for proof of origin and material composition, closer collaboration with suppliers and partners is necessary. To this end, new interfaces may need to be established in areas of the supply chain that are difficult to monitor. 

Furthermore, systems for capturing, managing, and providing product and material data must be able to integrate not only internal but also external data sources and read their content.  

The close interdependence of the diverse and complex process steps may also require a procedural realignment in which clear responsibilities within companies must be defined. 

European regulatory requirements thus define a framework but often leave companies some leeway in implementation. This leads to significant problems, particularly with regard to the required interoperability of the systems used. Accordingly, questions regarding the concrete implementation of the Battery Passport, standards such as OPC UA, and initiatives such as VDMA are becoming increasingly important in the creation of interoperable traceability solutions.