Battery carbon footprint verification: what to prepare for an independent LCA review

A life cycle assessment (LCA) of a battery can be reviewed by 2 very different third parties, depending on what the result will be used for. The carbon footprint declaration required by the EU Batteries Regulation goes through a notified body, which visits the factories. A study published to compare a product with a competitor's goes through a critical review under the ISO 14044 standard. In each of the 2 cases the file rests on 3 elements: factory data for the cells and active materials, proof of the electricity mix, and a study that documents every choice.

The calculation rules, however, have not yet been adopted. The Commission's draft act for electric vehicle batteries was published for feedback on 30 April 2024, and the Joint Research Centre (JRC) published its rules for industrial batteries in April 2025. A manufacturer preparing its file today works from these 2 documents, knowing that they may still change.

1Who reviews a battery LCA: an expert, a review panel or a notified body?

It depends on what the figure will be used for, as with the verification of an in-house carbon footprint assessment (in French) (in French). The EU Batteries Regulation requires a carbon footprint declaration for electric vehicle batteries, light means of transport batteries and rechargeable industrial batteries above 2 kWh. Everything else, whether a published comparison, a customer file or an internal study, is a matter for the standard or the contract.

The notified body, for the regulatory declaration

Article 17 of the Regulation, in its consolidated version of 13 August 2026, excludes self-checking for the carbon footprint. The declaration goes through one of the 2 modules involving a notified body, set out in Annex VIII:

• For a battery manufactured in series, module D1: the notified body approves the manufacturer's quality system after an audit that includes a visit to the facilities.
• Still for series production, it then carries out periodic audits in which it checks at least the carbon footprint values and the correct application of the method, and it may visit without notice.
• For a battery manufactured as a single unit, module G: the body examines the battery, issues a certificate of conformity and affixes its identification number to it.
• In each of the 2 cases, the manufacturer keeps the certificates and decisions for 10 years after the battery is placed on the market, available to the authorities.

Article 25 of the same Regulation sets out the independence of the body: neither it nor its staff may design, manufacture or distribute the batteries they assess, or carry out any activity that would threaten their judgement. The list of bodies notified under the Regulation can be consulted in the Commission's NANDO database. The provider that calculated the footprint therefore cannot verify it, as with the verification of an FDES (in French) (in French) (the French format of environmental product declaration for construction products).

The critical review, for a comparison or a customer

A critical review follows clause 6 of the ISO 14044 standard. It is mandatory for a published comparison, with a panel of interested parties of at least 3 members, and optional elsewhere under the standard; a customer may nevertheless require it in its tender specification. Our article on choosing an independent expert (in French) (in French) describes how a critical review of an LCA works, and its price (in French) (in French) varies mainly with the number of reviewers.

The 2 routes do not replace each other. A critical review report is not a regulatory verification. The opinion of a notified body covers only conformity with the European method, not a comparative statement, which is governed separately by the rules on environmental claims. A review carried out before submission does, however, serve as a dress rehearsal: it spots the gaps in the file while they can still be filled.

2What does the notified body verify, and under which rules?

The notified body verifies that the carbon footprint declaration complies with the method set by the delegated act, and that act is still missing. For electric vehicles, the draft act and its annex were published for public feedback on 30 April 2024 and received 127 contributions; the initiative page shows no adoption date at 17 October 2026. For industrial batteries, the April 2025 report of the Joint Research Centre, the JRC, serves as the technical basis.

What the body checks

Section 3.2 of the draft annex requires it to check that the data are consistent, reliable and traceable and that the calculations are correct. Its checks cover 4 points:

• It checks each secondary dataset and each piece of company-specific data for coverage, precision, representativeness, source and uncertainty.
• It verifies that the electricity modelling rules have been applied, along with unit conversions and estimation methods.
• For a battery manufactured in series, it visits the manufacturer's premises, the cell, anode and cathode plants, and those producing the active materials.
• It identifies uncertainties greater than expected and measures their effect on the total footprint.

It reads 2 documents. The full study contains the inventory tables, datasets, allocation factors and evidence. Its public version gives the footprint by life cycle stage, the data quality rating and the electricity mix used.

A rule that forces you to start again

The draft adds a rule that weighs on the long term: if the footprint increases by more than 10%, through a change of supplier, material origin, process or electricity, the battery becomes a new model. A new calculation and a new declaration are then required, and therefore a new verification.

3Which primary data should you collect for cells and active materials?

All main production is modelled with company-specific data: cathode and anode active materials, electrodes, electrolyte, cells, modules and pack, then distribution. For the most relevant upstream stages, such as cobalt, nickel, lithium or graphite precursors, the manufacturer chooses between a dataset from the Commission's list and one specific to its supplier.

What the factory must be able to show

The collection rules, taken up in the JRC report, are precise and verifiable:

• Data are the average of one year, except for a new line, whose first 6 months may be excluded from collection.
• Energy is measured as close to the workshops as possible, whether for electrode coating, assembly, cell formation or dry-room air conditioning.
• The bill of materials reflects the actual yields of the site, including manufacturing scrap and cells rejected at end-of-line testing.
• A quality system, ISO 9001, ISO 14001 or EMAS, must show that the data were collected and managed correctly.

A supplier that refuses to hand over its full inventory may provide an aggregated dataset, directly or through a third party. The manufacturer must then ensure that the notified body receives from the supplier all the information it needs. According to the report on industrial batteries, this dataset contains at least the footprint per kg or per kWh, by stage, and the content of 16 elements, including cobalt, nickel and lithium. This is the same logic as the carbon data requested from suppliers in a corporate carbon footprint assessment.

For company-specific data on an upstream stage, the report sets a maximum quality rating of 2.5 or 3, depending on whether an acceptable secondary dataset exists. The calculation method, based on the Product Environmental Footprint, known as PEF, and the choice of data are covered in our guide to carrying out an industrial battery LCA, and the heaviest items of a battery show where to concentrate data collection.

4How do you prove the electricity mix used in production?

By default, the draft annex uses the average consumption mix of the country of each factory. It makes only one exception: electricity produced in the same installation or delivered by a direct line, within the meaning of the European Electricity Directive 2019/944. Recital 5 of the draft act rules out contractual instruments, including guarantees of origin and power purchase agreements through the grid, because double counting outside the Union cannot be excluded.

The evidence to gather

To claim directly connected electricity, the study must provide the proof, in the form of these documents:

• The connection diagram showing generation on the site, or the direct line to the factory, without passing through the public grid.
• The annual records of generation and of injection into the grid, since the electricity claimed cannot exceed generation minus injection.
• The records of withdrawal from the grid, because any electricity taken from the grid, even as a top-up, counts at the country's average mix.
• Proof that no certificate attached to this generation has been sold to a third party, failing which it reverts to the average mix.

The Joint Research Centre report on industrial batteries refers to the final act on electric vehicles for the modelling of electricity. A calculation made today with a green power purchase agreement may therefore have to be redone. The country's mix matters, even though materials weigh more, as our article on what makes up the footprint of a battery shows.

5Which pitfalls are specific to batteries?

The pitfalls of a battery LCA come down to 2 things: calculation rules specific to the sector, and a timetable that is not yet fixed.

Rules that change from one battery to another

Several rules do not exist in the general method, or change from one battery category to another:

• The functional unit relates to the energy delivered over the whole life: for an industrial battery, it depends on the declared lifetime in cycles or years, which must be the same as in the technical documentation.
• Economic allocation applies when the prices of 2 co-products differ by more than a factor of 10 in the draft for vehicles, or when their economic values differ by more than a factor of 5 in the report on industrial batteries.
• A 1% cut-off by mass is allowed per component, but the mass difference must be reallocated and reported in the study.
• Recycled content counts only if proven, and end of life follows the circular footprint formula, with default values unless the company's own recycling is proven.
• Process emissions covered by the European carbon market are calculated under Implementing Regulation (EU) 2018/2066, and those from chemical reactions by stoichiometry.

A timetable that is moving

The declaration will apply 12 months after the entry into force of the delegated act and of the implementing act for electric vehicles, and 18 months after theirs for industrial batteries. A study based on a draft may have to be redone on the adopted text: it is better to keep a parameterised model than a fixed result. The same checks apply to any LCA calculated with software (in French) (in French).

6How should you organise the review and the verification?

The critical review covers the study; the verification by the notified body covers the study and the sites. The 2 are prepared with the same file, in an order that avoids back-and-forth.

The order of work

Verification takes place in several factories, often in several countries. A working order avoids discovering the gaps on the day of the audit:

• Fix the scope, that is the battery category, the model, the factory and the manufacturing mode, which determines module D1 or G.
• Collect the data of the active material and cell factories, with the suppliers, before modelling.
• Have the study reviewed by an independent expert, on the most exposed points: electricity, allocation, the functional unit and recycled content.
• Correct, then submit the file to a notified body chosen by the manufacturer, allowing for access to the suppliers' sites.

Choosing the notified body

Before signing, 4 points should be checked with the body:

• Its notification covers Regulation (EU) 2023/1542, the battery category and the module concerned, D1 or G, which the NANDO database shows for each body.
• Its audit team includes at least one member who knows the product group and its technology, as Annex VIII requires for module D1.
• It can visit the suppliers' cell and active material factories, often outside Europe, and write its reports in a language the manufacturer accepts.
• Neither it nor its staff has advised the manufacturer on this battery: Article 25 expressly refers to consultancy services.

Cost and reuse of data

There is no public price list for verification by a notified body. The calculation itself follows the orders of magnitude in our article on the cost of an LCA. The declaration also feeds the battery passport and, more broadly, the Digital Product Passport (DPP): data verified once are used several times, up to the DPP calculation method.

At Projet Celsius, the first item we ask for is evidence: the energy records by workshop and the yields of the cell factories, which suppliers are not used to sharing. We carry out LCAs and critical reviews under ISO 14044; verification of the declaration then falls to an independent notified body, which the manufacturer chooses. A team that wants to carry out its own first product LCA can train with our LCA training course.

7Key takeaways

• The regulatory declaration goes through a notified body, which visits the factories; a published comparison goes through a review panel.
• The rules come from a 2024 draft act and a 2025 report, and no text has been adopted at 17 October 2026.
• All production, from active materials to the pack, is modelled with factory data, averaged over 1 year.
• Electricity counts at the country's average mix, unless on-site generation or a direct line is proven.
• Have the study reviewed before submission, on electricity, allocation and the functional unit.

For the Regulation as a whole, see our guide to the Batteries Regulation; for the calculation, our guide to the LCA of an industrial battery.

Further resources

Frequently asked questions

1Who verifies the carbon footprint declaration of a battery?

A notified body under Regulation (EU) 2023/1542, through module D1 for a battery manufactured in series or module G for a battery manufactured as a single unit. Self-checking is not permitted for the carbon footprint. The body must be independent of the manufacturer, its partners and its investors, and the list of bodies can be consulted in the Commission's NANDO database.

2Is an ISO 14044 critical review enough for the Batteries Regulation?

No. A critical review judges an LCA against ISO 14044; regulatory verification judges the declaration against the method in the delegated act, with factory visits. A review carried out before submission remains useful for spotting the gaps in the file, but it does not replace the notified body.

3When does the carbon footprint declaration become mandatory?

For electric vehicle batteries, 12 months after the entry into force of the delegated act and of the implementing act, counting from the later of the two; for industrial batteries above 2 kWh, 18 months after their own act; and for light means of transport, 18 August 2028 at the earliest. At 17 October 2026, none of these acts has been adopted: the draft for vehicles dates from April 2024.

4Can guarantees of origin be used for the electricity mix of a cell factory?

Not under the April 2024 draft act: it uses the country's average consumption mix and rules out purchase contracts and guarantees of origin. Only electricity produced on the site or delivered by a direct line can be counted separately, backed by proof of generation and injection. The final text may still change this point.

5What data must a cathode supplier provide?

Either its full inventory, or an aggregated dataset specific to its factory, passed on directly or through a third party. This dataset gives at least the footprint per kg or per kWh, by life cycle stage, the product quality parameters and the content of 15 elements in the draft for vehicles, 16 in the report on industrial batteries, including cobalt, nickel and lithium. The notified body must be able to receive the detail.

6What happens if the footprint increases after the declaration?

Under the draft act, an increase of more than 10% due to a change of materials, suppliers, process or electricity makes the battery a new model. The manufacturer then redoes the calculation and the declaration, and the notified body verifies again.

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