The carbon footprint in your battery passport: declaration first, A–G class later.

Of the hundred-plus data points in an EU battery passport, the carbon footprint block is the one that demands real measurement rather than paperwork. From 18 February 2027 the passport must carry a carbon footprint declaration — a cradle-to-gate figure per kWh, calculated under a PEFCR-based methodology. But that is only the first step: a mandatory A–G performance class follows later, and maximum thresholds later still. The passport you publish in 2027 will not be the passport you are judged on in 2029.

In one line: the battery passport carries a PEFCR-based cradle-to-gate carbon footprint per kWh from 18 February 2027, an A–G performance class phases in afterwards (indicatively 2028 for EV batteries), and maximum thresholds come later still — a staircase of obligations that lands on passports already published.

The CF declaration: what it is

The carbon footprint declaration states the battery's life-cycle greenhouse-gas emissions from raw-material extraction through manufacturing to the factory gate — cradle-to-gate — expressed per kWh of the battery's total energy over its service life. The methodology follows a Product Environmental Footprint Category Rules (PEFCR) approach specific to batteries, so competing manufacturers calculate on comparable terms rather than choosing flattering system boundaries. From 18 February 2027, this declaration is part of the battery passport for every in-scope battery: EV, LMT and industrial above 2 kWh.

The A–G class and, later, maximum thresholds

The declaration is stage one of three. Stage two is a carbon footprint performance class — an A-to-G rating, like an energy label for embedded emissions — which becomes mandatory after the passport itself, indicatively from 2028 for EV batteries, with other categories following. Stage three, later still, is maximum carbon footprint thresholds: batteries above the limit will not be placeable on the EU market at all. Exact dates for the later stages depend on implementing acts and should be treated as indicative — but the sequence itself is written into the regulation. A battery that scrapes into class F may be sellable in 2028 and unsellable once thresholds bite.

The data you need to calculate it

A defensible cradle-to-gate figure needs primary data from the actual supply chain, not textbook averages:

Energy mix at cell and pack production sites — grid electricity, on-site generation, power purchase agreements. This is usually the single largest lever on the result.
Process data — material inputs, yields and scrap rates for electrode manufacturing, cell assembly and formation.
Upstream material footprints — cathode and anode materials, lithium, nickel, cobalt and their precursors.
Transport — modes and distances for materials and components between supply-chain stages.

Most of this sits with your cell supplier, in their documents and their format. Assembling it into an auditable declaration is a documentation exercise as much as an engineering one.

Why "publish once" is the wrong mental model

The carbon footprint block is the clearest proof that a battery passport is not a one-off filing. Obligations keep landing after first publication: the class rating arrives after the declaration, thresholds after the class, and any change in your energy mix, supplier or process invalidates the number you published. A passport must also remain accessible and accurate for the battery's regulated lifetime. That is why PassPer treats passports as living records: Drift Guard continuously re-validates published passport data against the current rule set and your current source documents, and flags when a change — regulatory or operational — means your declaration no longer holds.

Frequently asked questions

What exactly does "cradle-to-gate" cover?

Everything from raw-material extraction through materials processing, cell manufacturing and pack assembly, up to the point the battery leaves the factory gate — expressed per kWh of the battery's total energy over its service life. The use phase and end-of-life are outside the declaration's boundary.

When does the A–G carbon footprint class become mandatory?

After the declaration itself. The declaration is part of the passport from 18 February 2027; the performance class phases in afterwards, indicatively from 2028 for EV batteries, with exact timing set by implementing acts. Treat published dates for the class and the later maximum thresholds as indicative until those acts are adopted.

Can we use industry-average data instead of our supplier's real figures?

Only to a limited degree. The PEFCR-based methodology pushes towards primary data for the processes you and your suppliers control — above all the electricity mix at manufacturing sites, which typically dominates the result. A declaration built on generic averages is both less defensible and usually worse, since averages rarely credit a clean energy mix.

We published our passport — is the carbon footprint work done?

No. The A–G class and the maximum thresholds arrive after first publication, and any change in energy mix, supplier or process can invalidate your declared figure. The passport must stay accurate for the battery's regulated lifetime, which is why continuous re-validation of published data against current rules and current source documents matters.

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