Carbon Footprint in the Battery Passport

Why the Carbon Footprint Becomes Mandatory

Battery production is energy-intensive. Studies show that between 30 and 70 percent of a battery's total lifecycle emissions originate during the manufacturing phase — depending 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: from August 2025, manufacturers of EV batteries and industrial batteries with a capacity exceeding 2 kWh must submit a carbon footprint declaration. From August 2028, performance classes and maximum thresholds will additionally come into effect — 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 carbon footprint in the battery passport follows a cradle-to-gate approach. This means: all greenhouse gas emissions from the cradle (raw material extraction) to the gate (finished battery, ready for shipment) are captured. The use phase and end-of-life (recycling, disposal) are not included in the calculation — the focus lies on emissions that the manufacturer can directly influence.

Specifically, the cradle-to-gate approach encompasses the following stages:

• Raw material extraction and processing: Mining and processing of key raw materials — including lithium, cobalt, nickel, manganese, and graphite. This covers mining activities, ore processing, chemical refining, and the production of precursors such as lithium hydroxide or nickel sulfate.
• Component manufacturing: Production of battery components — cathode, anode, electrolyte, separator, and cell casing. Each component has its own emission contribution, with the cathode typically accounting for the largest share.
• Cell manufacturing: Actual cell production includes electrode coating, cell assembly (stacking or winding), electrolyte filling, formation (initial charge/discharge cycles), and aging tests. Energy demand in this phase is substantial — particularly for dry rooms and formation processes.
• Battery pack assembly: Integration of cells into modules and the finished battery pack, including the battery management system (BMS), thermal management, electrical wiring, and enclosure.
• Transport to point of sale: Emissions from transporting the finished battery from the production site to the customer or distribution point — including packaging and logistics.

The cradle-to-gate approach captures the entire chain from raw material extraction through component manufacturing, cell production, battery pack assembly, and transport. Each of these stages requires specific emission data and a clear definition of system boundaries.

The exact system boundaries — defining which processes and material flows are included and excluded — are laid out in the EU Delegated Act on carbon footprint rules for batteries. This delineation is critical, as even small differences in system boundary definitions can change the result by 10 to 20 percent.

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 specified in the Delegated Acts of the EU Battery Regulation.

Performance Classes and Thresholds

From August 2028, 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. The classes range from A (lowest carbon footprint) to E (highest carbon footprint) and will be visibly documented on the battery passport.

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 for performance classes from 2028. 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 by 30 to 50 percent 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.

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 the prescribed PEFCR methodology and the results are documented in a traceable manner. 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. Additionally, the European Commission provides the European Life Cycle Database (ELCD). 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 August 2025, initially for EV batteries and industrial batteries above 2 kWh. For LMT batteries (Light Means of Transport, e.g., e-bike and e-scooter batteries), the carbon footprint requirements also apply according to the current status; however, the digital battery passport — which contains the carbon footprint data — does not become mandatory for LMT batteries until February 2027. Check the current status of the Delegated Acts for exact deadlines.

What happens if my battery exceeds the threshold?

From August 2028, 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.