A Digital Battery Passport provides information about a battery throughout its lifecycle. But what happens when that history is incomplete?
Battery manufacturers, original equipment manufacturers (OEMs), and data teams may encounter missing production records, incomplete usage histories, unavailable supplier information, or gaps caused by disconnected systems. These challenges become particularly significant when batteries change ownership, enter second-life applications or reach recycling facilities.
In our previous article, How To Manage Changes To Battery Passport Data Over Time?, we explored how organisations can manage updates and preserve the history of changing information. Missing historical data presents a related challenge: how can organisations maintain a trustworthy Battery Passport when some of the original information cannot be recovered?
The answer begins with understanding what is missing, identifying reliable sources and making the limitations of the available data clear.
Why Does Historical Battery Data Go Missing?
Battery data is generated by different organisations and systems throughout a battery's lifecycle. However, these systems are not always designed to maintain a continuous record.
Common causes of missing historical battery data include:
→ Legacy systems: Older batteries may have been manufactured or deployed before digital record-keeping became standard.
→ Disconnected data systems: Information may be stored in separate enterprise resource planning (ERP), manufacturing, battery management or maintenance systems.
→ Ownership transfers: Records may not be transferred when batteries move between manufacturers, vehicle owners, fleet operators or second-life providers.
→ Offline operation: Batteries may operate without continuous connectivity, leaving gaps in operational or telemetry records.
→ Supplier data gaps: Material composition, recycled content or other supply chain information may be incomplete or unavailable.
→ Inconsistent data formats: Different organisations may use incompatible formats, units or identifiers, making historical records difficult to combine.
These gaps can affect decisions about battery performance, safety, compliance, reuse and recycling. Without sufficient historical context, organisations may struggle to establish how a battery was manufactured, used or maintained.
Step 1: Identify What is Missing
The first step is to assess the available information against the data required for the relevant Battery Passport.
Not every missing data point has the same significance. A missing manufacturing date, an incomplete maintenance record and an unavailable State of Health (SoH) measurement can have different implications depending on the battery, its lifecycle stage and the intended use of the information.
Organisations should create a data gap register that identifies the missing information, the affected battery or battery model, the relevant lifecycle stage and the reason the information is unavailable.
This assessment should distinguish between information that has never been collected, information that exists but cannot currently be accessed, and information that may be recoverable from another source.
A structured gap assessment also helps teams prioritise the information that needs further investigation.
Step 2: Recover Battery Passport Data From Existing Sources
Before considering estimates, organisations should investigate whether the missing information can be recovered from existing records.
Potential sources include manufacturing execution systems, quality management records, supplier declarations, maintenance logs, battery management systems, warranty databases and historical inspection reports.
For batteries that have changed ownership, previous operators or service providers may hold relevant records. Where information comes from external organisations, data owners should establish whether the records refer to the correct battery, component or production batch.
This process requires reliable identifiers and a clear understanding of where the information originated.
As explained in Battery Passport Data Lineage: From Source System to Published Passport, tracing information back to its original source helps organisations understand how data was created and transferred.
Recovered records should be checked for completeness, consistency and supporting evidence before being incorporated into the Battery Passport.
Step 3: Distinguish Verified Data from Estimates
Sometimes, historical information cannot be recovered. In such cases, organisations may consider whether a missing value can be estimated using a suitable methodology.
However, an estimate must not be presented as a verified historical measurement.
For example, a battery's current condition may help inform an assessment of its likely degradation, but it cannot establish its exact historical State of Health at a particular point in time.
Similarly, a model-based estimate of energy throughput cannot automatically replace a missing operational record.
Where estimation is appropriate for a specific analytical purpose, the organisation should document the methodology, assumptions, input data, uncertainty and intended use of the result. The estimated value should remain distinguishable from measured or independently verified information.
An estimate should not be used to fill a mandatory Battery Passport field unless the applicable requirements permit that approach.
The BASE project has also explored the potential of AI and machine learning to address incomplete lifecycle datasets in Intelligent Battery Insights: Using AI & Machine Learning to Close Gaps in Missing Battery Lifecycle Data.
These methods may help identify patterns and support analysis, but their outputs require appropriate validation and transparent treatment of uncertainty.
Step 4: Preserve Evidence and Document Data Limitations
When information cannot be recovered, the organisation should preserve evidence of the investigation and clearly document the remaining gap.
A practical data gap record can include the missing data point, the affected battery, the sources investigated, the reason the information remains unavailable, any alternative evidence and the responsible data owner.
This creates an auditable record of what is known, what remains uncertain and what steps have been taken to address the issue.
The organisation should also define how the gap will be handled. Depending on the information and applicable requirements, this may involve further investigation, escalation to a supplier, a qualified analytical estimate or a documented decision that the information cannot be established.
Missing data should not be silently converted into a default value, copied from an unrelated battery or replaced with an unsupported assumption.
Our article on Battery Passport Data Provenance: How to Prove Battery Passport Data Origins explains how source information and supporting evidence contribute to data trustworthiness.
Step 5: Validate the Available Data
Once recovered or newly collected information is ready for use, it should be checked before being incorporated into the Battery Passport.
Validation may include checking whether the value follows the required format, falls within a plausible range, matches the relevant battery identifier and is consistent with other available records.
For estimated information, validation should also consider whether the methodology is suitable for the intended purpose and whether its limitations are clearly recorded.
Where the original information remains unavailable, validation cannot establish facts that the evidence does not support. It can, however, confirm that the available information has been handled consistently and transparently.
Organisations can use the principles discussed in How to Validate Battery Passport Data Before Publication: A Practical Data Quality Guide to strengthen these checks.
Step 6: Manage Data Gaps Across the Battery Lifecycle
Historical data gaps can become more challenging when a battery enters a new lifecycle stage.
A battery transferred from an electric vehicle to a stationary energy storage application may arrive with incomplete usage or maintenance records. A recycler may receive a battery with limited information about its previous operation.
In these situations, the receiving organisation should assess the available evidence, identify the information needed for its intended activities and document any limitations.
New measurements and inspections can improve the available record, but they do not automatically reconstruct the battery's complete history.
Organisations should preserve the distinction between historical information, newly collected data and any derived assessments. Where a battery undergoes repurposing or remanufacturing, the applicable Battery Passport requirements concerning new Passports and links to earlier records must also be considered.
What Does the EU Batteries Regulation Say About Missing Data?
Regulation (EU) 2023/1542 establishes Battery Passport requirements for electric vehicle batteries, light means of transport batteries and industrial batteries above 2 kWh, from 18 February 2027.
Article 77 requires the economic operator placing a battery on the market to ensure that the Passport information is accurate, complete and up to date. Article 78 addresses data authentication, reliability, integrity and controlled access to information.
The regulation does not provide a blanket exemption from these obligations simply because historical information is unavailable. Organisations should therefore assess missing data against the applicable requirements rather than assuming that an estimate or an empty field is automatically acceptable.
How BASE Supports More Trustworthy Battery Data
The BASE project is developing, validating and implementing a trusted and interoperable Digital Battery Passport framework to support secure, transparent data management across the battery value chain.
Its work on traceability, data authenticity verification, interoperability and privacy by design is relevant to the challenge of fragmented lifecycle information. By supporting connections between data sources and battery records, BASE contributes to the broader objective of making battery information more traceable and trustworthy.
Addressing missing historical data requires organisations to understand the origin and limitations of the information they hold, preserve supporting evidence and maintain a clear distinction between verified records and derived assessments. These principles align with BASE's wider work towards a reliable Digital Battery Passport ecosystem.
From Incomplete Records to More Reliable Battery Histories
Missing historical battery data is a practical challenge for manufacturers, OEMs and organisations working across the battery lifecycle.
The most reliable response is to investigate recoverable records, assess the significance of each gap, validate available information and document what remains unknown. Where estimates are appropriate, their assumptions and limitations should remain visible.
A trustworthy Battery Passport does not require organisations to pretend that every historical record is complete. It requires them to manage the information they have responsibly, explain its limitations and build a clearer record as the battery moves through its lifecycle.
The BASE project has received funding from the Horizon Europe Framework Programme (HORIZON) Research and Innovation Actions under grant agreement No. 101157200.
References & Resources
European Union - Regulation (EU) 2023/1542 Concerning Batteries and Waste Batteries: https://eur-lex.europa.eu/eli/reg/2023/1542/oj
European Commission - Guidance to Support Preparations for the Digital Batteries Passport: https://single-market-economy.ec.europa.eu/news/guidance-support-preparations-digital-batteries-passport-2026-08-21_en
European Commission - Digital Product Passport For Batteries: https://single-market-economy.ec.europa.eu/single-market/digital-product-passport/batteries_en
Regulation (EU) 2024/1781, the Ecodesign for Sustainable Products Regulation: https://eur-lex.europa.eu/eli/reg/2024/1781/oj/eng
BASE Project - Intelligent Battery Insights Using AI and Machine Learning: https://www.base-batterypassport.com/blog/technology-7/intelligent-battery-insights-using-ai-machine-learning-to-close-gaps-in-missing-battery-lifecycle-data-110
BASE Project - Battery Passport Data Lineage: From Source System To Published Passport: https://www.base-batterypassport.com/blog/traceability-9/battery-passport-data-lineage-138
BASE Project - Battery Passport Data Provenance: How To Prove Battery Passport Data Origins: https://www.base-batterypassport.com/blog/regulations-4/battery-passport-data-provenance-data-origin-139