Carbon Footprint in the Battery Passport

Why the Carbon Footprint Becomes Mandatory

Battery production is energy-intensive. A large share of lifecycle emissions arises during the manufacturing phase; exactly how much depends on the energy mix at the production site and the origin of the raw materials used. Given the rapidly growing demand for batteries for electric vehicles, stationary energy storage, and light means of transport, the European Union has recognized that transparency about these emissions is a decisive lever for climate protection.

The EU Battery Regulation (EU 2023/1542) therefore mandates that the carbon footprint of batteries must be documented and disclosed. The timeline is phased: the carbon footprint declaration applies at the earliest 12 months after the delegated act on the calculation methodology and the implementing act on the declaration format have entered into force for EV batteries, and at the earliest 18 months after that point for rechargeable industrial batteries above 2 kWh. Article 7(1) also names the fixed dates 18 February 2025 and 18 February 2026, but whichever point in time is the latest applies, and both dates have passed without either act being adopted. The carbon footprint performance classes (Article 7(2)) and the maximum carbon footprint threshold (Article 7(3)) follow the same mechanism: for EV batteries they apply from 18 August 2026 and 18 February 2028 respectively, or 18 months after the entry into force of the acts required for them, whichever is the later date. Batteries that exceed the threshold will no longer be permitted on the EU market.

The overarching goal is clear: the EU aims to measurably reduce emissions in battery production and create incentives for more climate-friendly manufacturing. Manufacturers who invest early in low-emission production processes and renewable energy gain a competitive advantage. The carbon footprint thus evolves from a mere reporting obligation into a strategic differentiator.

The carbon footprint obligation is embedded within the broader framework of the European Green Deal and EU climate targets, which aim for at least a 55 percent reduction in greenhouse gas emissions by 2030. Batteries play a dual role: on one hand, they are a key technology for decarbonizing transport and the energy system; on the other, they themselves cause significant emissions during manufacturing. The carbon footprint documentation requirement aims to close this gap.

Which Lifecycle Stages are Covered?

The system boundary is set by Annex II No. 4 of the EU Battery Regulation. It names four lifecycle stages that must be included, and Article 7(1)(e) requires the carbon footprint to be broken down by exactly these stages. The use phase is the only stage that is left out, because manufacturers do not directly influence it. End of life and recycling, by contrast, are part of the calculation, so the scope reaches beyond a pure cradle to gate view.

The four stages of Annex II No. 4:

• Raw material acquisition and pre-processing: Mining and other sourcing, pre-processing and transport of all active materials up to the production of battery cells and battery components (active materials, separator, electrolyte, housing, active and passive battery components) and electrical or electronic components. In practice this covers lithium, cobalt, nickel, manganese and graphite, plus ore processing, chemical refining and precursors such as lithium hydroxide or nickel sulfate.
• Main product production: Assembly of the battery cells and assembly of the battery from the cells and the electrical or electronic components. This includes electrode coating, cell assembly (stacking or winding), electrolyte filling, formation and aging tests, and the integration of cells into modules and into the finished pack with battery management system, thermal management, wiring and enclosure.
• Distribution: Transport to the point of sale, including packaging and logistics.
• End of life and recycling: Collection, dismantling and recycling of the battery.

Annex II No. 4 also excludes two production steps: the manufacture of the equipment used for battery assembly and recycling, and the pack assembly step carried out with the original equipment manufacturer's own system components.

The system boundary runs from raw material acquisition through production and distribution to end of life and recycling. Only the use phase stays outside. Each stage requires its own emission data, and Article 7(1)(e) requires the result to be reported per stage.

The exact system boundaries, defining which processes and material flows are included and excluded, are to be laid down by the delegated act under Article 7(1). That act has not been adopted, so the boundaries are not yet binding anywhere. This delineation is critical: we deliberately name no percentage range here, because Annex II leaves the calculation method to the delegated act that is still outstanding, and without uniform system boundaries the figures in circulation are not comparable.

Calculation Methodology

The calculation of a battery's carbon footprint is based on the Product Environmental Footprint Category Rules (PEFCR) for rechargeable batteries. These rules define a uniform methodology that ensures results from different manufacturers are comparable.

Key elements of the calculation methodology:

• Functional unit: The carbon footprint is referenced to a functional unit of 1 kWh of total energy delivered by the battery over its entire service life. The result is expressed in kg CO₂ equivalent per kWh (kg CO₂e/kWh).
• Data sources: A distinction is made between primary data and secondary data. Primary data comes from own production, for example actual energy consumption at the site, measured process emissions, and real material consumption. Secondary data comes from life cycle assessment databases such as ecoinvent or GaBi and is used where site-specific data is not available.
• Calculation formula: At its core, the calculation follows the principle: activity data × emission factor = carbon footprint per stage. Activity data describes consumption (e.g., kWh of electricity, kg of material), while emission factors assign the corresponding greenhouse gas emissions to that consumption.
• Allocation rules: When production processes yield multiple products simultaneously (e.g., a refinery processing nickel and cobalt together), emissions must be allocated across the individual products according to defined rules.

To put results into perspective: the carbon footprint of a typical EV battery currently ranges between 50 and 150 kg CO₂e/kWh, depending on the production location, the local energy mix, and the efficiency of production processes. Batteries manufactured in countries with a high share of renewable energy (e.g., Sweden, Norway) achieve significantly lower values than those from regions with coal-heavy electricity generation.

In certain cases, independent third-party verification of the carbon footprint calculation may be required. The precise verification requirements are to be set by the delegated acts under the Battery Regulation, which are still outstanding.

Performance Classes and Thresholds

For EV batteries from 18 August 2026, tied to the corresponding delegated act, the EU takes the next step: batteries will be classified into carbon footprint performance classes, comparable to the EU energy label that consumers know from refrigerators and washing machines. Annex II No. 8 of the EU Battery Regulation only states that category A is the highest class, the one with the lowest lifecycle carbon footprint. How many classes there will be and where their thresholds lie is set by a delegated act that has not been adopted. Under Article 7(2) the performance class is shown on a label on the battery, and the non-binding European Commission guidance of 28 July 2026 lists the carbon footprint label as “not to be filled/displayed as of February 2027”.

The classification is based on the statistical distribution of carbon footprint values across all batteries offered on the EU market. Manufacturers with below-average emissions will be placed in a higher class and can market this as a quality and sustainability feature.

Furthermore, a maximum carbon footprint threshold will be defined. Batteries whose carbon footprint exceeds this limit will no longer be permitted for sale in the EU. The thresholds are intended to be progressively tightened to reflect technological progress and drive continuous improvement across the industry.

The implications are significant:

• Market access: Manufacturers with a high carbon footprint risk losing access to the EU market, one of the world's largest markets for batteries.
• Competitive dynamics: Performance classes create transparent competition for the lowest emissions. Battery buyers, particularly automotive manufacturers, will use the carbon footprint class as a selection criterion.
• Investment decisions: Location decisions for new battery factories will increasingly be influenced by the available energy mix and achievable carbon footprint values.

For manufacturers, this means: those who take carbon footprint documentation in the battery passport seriously early on and prepare their emission data properly will be ready when the performance classes actually take effect, which under Article 7(2) is 18 August 2026 for EV batteries or 18 months after the entry into force of the acts required for them, whichever is the later date. DIN SPEC 99100 defines the data structure in which carbon footprint information is stored in the battery passport.

Data Capture in Practice

The greatest challenge in carbon footprint accounting for batteries is not the calculation itself, but data capture across complex, global supply chains. A typical EV battery pack contains materials from a dozen countries, processed through multiple stages before cells are assembled at the production site.

A proven approach for systematic data capture:

1. Map your supply chain: Identify all Tier 1 suppliers (direct suppliers) and key Tier 2 suppliers (upstream suppliers). For the carbon footprint, suppliers of cathode material, anode material, electrolyte, and cell manufacturing are particularly relevant.
2. Capture own operational data: Collect primary data from your own production: energy consumption (electricity, gas, heat), material inputs, process emissions, transport routes. This data is typically available in ERP and MES systems.
3. Request supplier data: Request specific emission data from your suppliers, particularly the energy mix at the production site, process emissions, and transport distances. Standardized questionnaires facilitate this process.
4. Fill gaps with secondary data: Where no primary data is available, use recognized LCA databases. Note: secondary data is less accurate and may over- or underestimate the carbon footprint.
5. Calculate, verify, document: Consolidate the data, calculate the carbon footprint according to PEFCR methodology, have the result verified if required, and document everything comprehensively in the battery passport.

Software tools play a central role in data capture: they provide structured input forms, validate data against the prescribed schema, and support calculations. In DPP Hero, for example, the carbon footprint is mapped as Step 3 of the 7-step editor, with predefined fields for lifecycle stages, emission values, and calculation methodology according to DIN SPEC 99100.

A further practical tip: don't start data capture from scratch, leverage existing data sources. Many companies already have energy reports, material specifications, and supplier assessments that can serve as a starting point. Learn more about transitioning from existing data sources to a structured battery passport in the article From Excel to the Battery Passport.

Common Challenges

Carbon footprint accounting for batteries is methodologically demanding and comes with a range of practical challenges:

• Data availability: Not all suppliers can or will provide specific emission data. Particularly with raw material suppliers in the upstream supply chain (Tier 2 and Tier 3), primary data is often unavailable. In these cases, secondary data must be used, with corresponding uncertainties.
• Data quality: Even when data is available, quality varies considerably. Primary data from own measurements is precise, while industry averages from databases can deviate noticeably from actual values. Documentation of data quality and sources used is therefore mandatory.
• Supply chain complexity: Battery supply chains span multiple continents and dozens of suppliers. Supplier changes, intermediaries, and varying sourcing patterns further complicate consistent data capture.
• Methodological questions: Correct application of allocation rules, definition of system boundaries, and selection of appropriate emission factors require LCA expertise. Methodological errors can lead to significant deviations in results.
• Cost: Creating a complete carbon footprint assessment requires investment in LCA expertise (internal or external), software tools, databases, and potentially independent third-party verification. For smaller companies, this can represent a tangible financial burden.

Recommendations for getting started: Begin early, ideally at least 12 months before the regulatory deadline. Build robust relationships with your key suppliers and establish standardized processes for data collection. Use industry-standard questionnaires and tools to minimize effort for all parties. The earlier you start with data capture, the better prepared you will be for the upcoming performance classes and thresholds.

The three stages and their dates

Article 7 sets out three stages, each with its own date per battery type. The formula behind them matters: what applies is always the later of the two, the calendar date given or a period after the relevant act enters into force. Because those acts are still missing, none of the stages has been triggered.

So anyone selling you a carbon footprint declaration obligation as being in force today is confusing the calendar date with the trigger.

How many declarations a manufacturer needs

Not one per model, but one per battery model per manufacturing plant. That is what Article 7(1) says, and the declaration expressly names the geographical location of the plant. If you build the same model at three sites, you need three declarations with their own values. This is why the carbon footprint in the battery passport has to be thought of as a site property, not a product property.

Who verifies the figures

Not you, and not a freely chosen provider. The reliability of the data for the carbon footprint and the performance class is checked by a notified body as part of assessing your quality management system, together with the correct application of the calculation method. It then notifies you of the result. Plan this check in as a fixed part of the process, not as an exception.

Two traps: offsetting and power modeling

The first trap is spelled out in Annex II: climate offsets must not be included in the carbon footprint declaration. They may be stated separately as additional environmental information and used for communication, but they do not lower the declared figure. Pull offsets into the calculation and you report a number the Regulation does not recognize.

The second trap is still open. How the electricity used is modeled changes the result considerably: the site mix of the plant, the residual mix after contractually allocated volumes are deducted, guarantees of origin, or a direct power purchase agreement. The Regulation itself does not settle this; it depends on the calculation method under Annex II that is still outstanding. Until then: document which assumption you made, so the figure stays traceable later.

FAQ

Do I have to calculate the carbon footprint myself?

The responsibility for the accuracy of carbon footprint data lies with the economic operator, the manufacturer or importer of the battery. You can perform the calculation internally, engage an external LCA consultant, or choose a combination of both. What matters is that the calculation follows a traceable methodology, today usually the PEFCR for rechargeable batteries, and that the results are documented in full. A methodology only becomes binding with the delegated act under Article 7(1), which is still outstanding. Software tools for creating and managing battery passports can facilitate the structured entry and documentation of carbon footprint data.

Which databases can I use for secondary data?

The most widely used databases for life cycle assessments in the battery sector are ecoinvent and GaBi (now Sphera LCA). Both offer extensive datasets for raw materials, energy carriers, and industrial processes. The European Commission now runs the European Platform on Life Cycle Assessment with the EF reference package and the Life Cycle Data Network. The older European Life Cycle Database is no longer offered separately: its address now leads to the Life Cycle Data Network and the former developer page has been taken down. When selecting datasets, ensure they are current and regionally representative, an outdated global average value can significantly distort the actual footprint.

Does the carbon footprint requirement also apply to LMT batteries?

Yes, but with a time delay. The carbon footprint declaration becomes mandatory from 18 February 2025 for EV batteries and 18 February 2026 for industrial batteries above 2 kWh, in each case once the corresponding EU acts are in force. For LMT batteries (Light Means of Transport, e.g., e-bike and e-scooter batteries), Article 7(1)(c) names a deadline of their own: 18 August 2028, or 18 months after the corresponding acts enter into force, whichever is the later date. The battery passport itself becomes mandatory for these batteries on 18 February 2027, so the carbon footprint declaration inside it follows a year and a half later.

What happens if my battery exceeds the threshold?

From 18 February 2028 (for EV batteries, tied to the delegated act), batteries whose carbon footprint exceeds the defined maximum threshold will no longer be permitted on the EU market. This means: no sales, no imports, no market introduction across all 27 EU member states. The specific thresholds will be set by the European Commission based on market data and progressively tightened. Manufacturers should therefore not only monitor the current threshold but also factor the foreseeable tightening into their production planning.