Why Legacy Systems Cannot Support the Digital Battery Passport: The Hidden technical Debt inside OEM Plants

Executive Summary

When an Original Equipment Manufacturer (OEM) maps the requirements of the Digital Battery Passport (DBP) against its internal systems for the first time, the result is rarely straightforward. What appears on paper as a regulatory obligation quickly turns into a practical exercise in data architecture: missing fields, unclear ownership, inconsistent serialisation logic, and integration questions that were never previously urgent.

With the February 2027 requirement approaching for batteries above 2 kilowatt-hours (kWh), the real challenge is determining whether existing plant and Information Technology (IT) systems can deliver the level of serial-level transparency now expected. Most OEM environments operate established Manufacturing Execution Systems (MES), Product Lifecycle Management (PLM) platforms, Enterprise Resource Planning (ERP) systems, and increasingly advanced Battery Management Systems (BMS). Each performs its intended function. The difficulty emerges when these systems are expected to operate as a continuous, cross-company lifecycle infrastructure.

For vehicle OEMs placing batteries on the European Union (EU) market, the obligation lies in ensuring that supplier-provided battery data can be integrated, governed, and maintained across production, vehicle integration, use, and subsequent lifecycle stages. This level of structured, traceable continuity was not the original design objective of most plant architectures – and the gaps are now becoming visible.

Where the Gaps Become Visible

In production, Manufacturing Execution Systems (MES) capture work orders, quality checks, and batch information. Product Lifecycle Management (PLM) defines product structures and revisions. Enterprise Resource Planning (ERP/SAPs) records supplier data and transactions. Battery Management System (BMS) captures operational behaviour once the battery leaves the factory.

Individually, these data sets are rich, but when put together, in most cases, they are fragmented.

When OEMs attempt to align DBP data requirements with system outputs, several patterns emerge. Material provenance may be recorded but not linked consistently to serialised modules. Production identifiers may exist at batch level but not cascade cleanly to pack or cell level. BMS data may be technically available but not governed for external traceability purposes. While none of these gaps are dramatic in isolation, they become critical when regulatory transparency requires a single, coherent digital identity.

Integration Is the Real Work

 Therefore, the most underestimated effort over the next 12 months (until the EU Battery regulation comes in force – February 2027) will be integration.

OEMs will spend time reviewing how MES exports data, how PLM structures are versioned, how ERP master data is governed, and how BMS indicators can be standardised. They will need to define which department owns lifecycle updates. They will need to establish API layers capable of supporting secure, structured exchange. In many organisations, the DBP initiative might be the first time when manufacturing, sustainability, IT, procurement, and engineering are forced to examine the same data chain from end to end.

Serialisation and the Reality of Granularity

 One of the most revealing stress points lies in granularity. The Digital Battery Passport assumes that batteries, modules, and potentially cells can be uniquely identified and linked to material and production records.

For some OEMs, serialisation exists at pack level but not consistently below. For others, material information is stored at supplier batch level but not directly tied to finished goods identifiers. Bridging these differences requires changes in data modelling, not simply new reports. And this is where technical debt becomes visible: in assumptions made years ago about how much traceability would ever be required.

The BMS Question

Operational data introduces another layer of complexity. Battery Management Systems track state-of-charge, degradation behaviour, thermal events, and safety flags. The Digital Battery Passport raises the question of how much of this operational intelligence should inform lifecycle transparency.

Extracting, structuring, and governing BMS-derived indicators for regulatory or cross-actor visibility demands clear policies and technical standards. It also requires alignment between engineering teams who generate the data and compliance functions who may rely on it.

What This Means Strategically

When some think of the Digital Battery Passport as a documentation exercise, what it actually is – it is a structural test of whether OEM’s plant systems can support serial-level, lifecycle-ready transparency across organisational boundaries.

OEMs that approach it as a reporting obligation are likely to implement short-term fixes and layered interfaces. Those that treat it as an opportunity to modernise integration logic and clarify data governance will build more resilient infrastructure for future regulatory shifts.

From Seraph’s perspective, the next year will be defined by architecture reviews, interface redesign, and clearer data ownership across functions. For many organisations, this work has been delayed simply because there was no immediate trigger.

The Digital Battery Passport now provides that trigger. It brings long-standing integration questions into focus as a structured opportunity to modernise lifecycle traceability, strengthen supplier alignment, and build more resilient data foundations for the years ahead.

At Seraph, we help companies use circularity indicators not just to comply – but to compete. Whether it is redesigning for faster disassembly or benchmarking data flows for traceability, the future belongs to those who translate sustainability into smart economics. 

Ready to harness the DBP for operational advantage?

Do you need support, guidance and insights on automotive manufacturing excellence? Let’s talk  https://seraph.com/contact-us/

About Seraph  

Seraph is a global operations and strategy consulting firm, that leads value chain improvements, restructurings, and turnarounds. We unite the disparate roles in operationally intensive businesses to create efficient operations, bridging the divide from concept to production. High-level decision-makers in manufacturing and industrial organizations rely on us to solve complex issues and launch initiatives that ensure success and sustainable change.

Seraph is a member of the BASE Battery Passport for Transparency and Circularity consortium.

The BASE project has received funding from the Horizon Europe Framework Programme (HORIZON) Research and Innovation Actions under grant agreement No 101157200 

Visit the BASE website here: https://base-digibattpass.eu/