As the EU prepares for the full implementation of the Digital Battery Passport under Regulation (EU) 2023/1542, physical data carriers such as QR codes and, in some cases, NFC tags will become critical access points to structured battery lifecycle data.

From 18 February 2027, electric vehicle batteries, industrial batteries, and light means of transport batteries above 2 kWh must carry a digital record accessible via a data carrier on the battery itself. This requirement is clearly set out in the EU Battery Regulation (EU) 2023/1542, which mandates that each battery subject to the regulation be linked to a unique identifier and an accessible digital record.

However, batteries operate in demanding environments. Exposure to heat, vibration, chemical residues, moisture and mechanical abrasion can damage labels, etchings or embedded tags. This creates what we call the “Broken Link” problem: what happens when the physical access point to the Battery Passport is no longer readable?

For manufacturers, recyclers, service providers and regulators, this is not a theoretical question. It is a practical compliance and operational issue that requires robust technical and procedural protocols.

Significance of Physical Data Carriers in Digital Battery Passport

The EU Battery Regulation requires that the passport be accessible via a data carrier, commonly implemented as a QR code or similar machine-readable identifier, physically attached to the battery. The data carrier must ensure a reliable link to the electronic record stored in a compliant digital system.

In practice, QR codes are widely used because they are standardised under ISO/IEC 18004 and are designed to remain readable even if partially damaged, thanks to built-in error correction mechanisms. NFC tags, governed by ISO/IEC 14443 standards, offer an alternative or complementary access method and can be embedded within battery casings for added protection.

Despite these technical safeguards, physical degradation remains a risk. If a QR code becomes unreadable or an NFC tag is damaged, access to the passport via the battery surface may fail. Without appropriate fallback mechanisms, this can delay maintenance, disrupt resale or recycling processes, and complicate regulatory inspections.

The Operational Risks of a Broken Link

A damaged data carrier has the potential to create several interconnected risks across the battery lifecycle.

First, authorised stakeholders may be unable to retrieve safety, state-of-health or compliance information at the point of service or recycling.

Second, market surveillance authorities may encounter difficulties verifying conformity during inspections.

Third, uncertainty around battery identity may undermine traceability and data integrity, especially if multiple batteries share similar physical characteristics.

Given that the regulation emphasises traceability, interoperability and secure access to lifecycle data, the industry must treat the resilience of physical access mechanisms as a compliance priority.

Protocols for Mitigating the “Broken Link” Problem

Protocol 1: Redundant Identification Mechanisms

The most effective mitigation strategy is redundancy. A battery should not rely on a single physical data carrier.

Best practice includes:

• Permanent marking of the unique battery identifier on the housing through laser engraving or durable stamping
• Use of both QR codes and NFC tags where feasible
• Storage of the unique identifier in internal electronic systems, such as the battery management system

The EU Battery Regulation already requires a unique identifier linked to the passport. Ensuring that this identifier is also physically durable and independently readable provides a secondary route to retrieving passport data through central registries or manufacturer systems.

Redundancy protects traceability even if one access method fails.

Protocol 2: Central Registry And Backend Resolution

Even if the physical QR code is damaged, the battery’s unique identifier should remain resolvable within a compliant backend infrastructure.

The regulation foresees that passport data will be stored in a secure electronic system, and that authorised actors can access the relevant information through defined roles and permissions.

This architecture allows for lookup and retrieval via backend systems if the original QR code link is not scannable.

In practical terms, this means service providers or recyclers can manually enter a visible serial number or engraved identifier into a secure database to retrieve the correct passport record.

This protocol depends on consistent data synchronisation and accurate identifier management across the battery lifecycle.

Protocol 3: Verification And Re-Issuance Procedures

If a data carrier is confirmed to be damaged, there should be a controlled process for replacement or re-issuance.

This requires:

• Verification of the battery’s identity through internal serial numbers or manufacturer records
• Confirmation that the retrieved digital record corresponds to the physical unit
• Secure generation of a replacement QR label or reprogrammed NFC tag linked to the original passport

Any replacement process must maintain the integrity of the digital record and avoid duplication or misidentification. Clear audit trails are essential to prevent fraud or confusion in secondary markets.

Protocol 4: Durability Standards And Environmental Testing

Preventing the broken link problem begins at the design stage. QR labels and NFC tags should be tested for durability under realistic environmental conditions, including:

Temperature cycling

Mechanical abrasion

Chemical exposure

UV exposure

Standards relating to product marking, durability and traceability, along with general quality management frameworks such as ISO 9001, provide a basis for integrating resilience into manufacturing processes.

In high-risk industrial environments, embedding NFC chips beneath protective layers or engraving QR codes directly into metal housings can significantly reduce failure risk.

Protocol 5: Clear Access Policies For End-Of-Life Operators

Recyclers and repurposing facilities must be equipped with protocols for handling unreadable tags. This includes defined communication channels with manufacturers, secure lookup procedures and documented identity verification steps.

The EU Battery Regulation highlights the importance of traceability and information availability throughout the lifecycle, including at end-of-life. Ensuring that recyclers have alternative pathways to retrieve passport data is critical to achieving circularity and material recovery targets.

Without structured fallback mechanisms, damaged data carriers could slow recycling throughput and increase administrative burden.

How BASE Addresses The Broken Link Challenge

At BASE, we recognise that robust Digital Battery Passport systems must account for real-world physical wear and operational complexity. Our Digital Battery Passport framework emphasises redundant identification, secure backend resolution and interoperable data architectures that allow authorised stakeholders to retrieve records even if a QR code or NFC tag is compromised.

BASE supports structured unique identifiers, role-based access control and secure record linkage so that passport data remains accessible and verifiable across the lifecycle. By designing digital systems that anticipate physical degradation, we help strengthen trust, compliance and operational continuity.

Building a Resilient Digital Battery Passport Ecosystem

The Broken Link problem is not a marginal technical issue. It is a foreseeable operational reality in harsh industrial environments. Addressing it requires thoughtful design, redundancy, strong identifier governance and secure digital infrastructure.

As the EU Battery Passport moves towards mandatory implementation in 2027, organisations that design for resilience will reduce compliance risk, protect traceability and enhance trust across the supply chain. Ensuring that no battery becomes disconnected from its digital identity is central to achieving the transparency and circularity objectives of the EU Battery Regulation.

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

References:

Regulation (EU) 2023/1542 – EU Battery Regulation: https://eur-lex.europa.eu/eli/reg/2023/1542/oj

Regulation (EU) 2023/1542 consolidated version: https://eur-lex.europa.eu/eli/reg/2023/1542/2023-07-28/eng

ISO/IEC 18004:2024 – QR Code Standard: https://www.iso.org/standard/62021.html

ISO/IEC 14443 – NFC Proximity Cards Standard: https://www.iso.org/standard/73597.html

ISO 9001 – Quality Management Systems: https://www.iso.org/standard/62085.html