what technical data on capacity and power must be in the passport

Nominal capacity and original power are central

The passport fundamentally requests the nominal capacity in ampere-hours, the original power at nominal voltage, and the associated voltage itself. These are the figures with which a buyer or repair technician can technically position the battery: how much energy it delivers, at what voltage, and how it compares to the specification with which it originally entered the market. In addition, data must be included here on the power that the battery can deliver under different usage conditions, such as at high or low temperature, and on the expected service life expressed in charge cycles. The latter relates to another part of the passport, namely the current state in which the battery finds itself — a figure that is separately recorded alongside the original specifications.

For batteries within the scope, not for every detail of cell chemistry

This data applies to the categories of batteries covered by the regulation: EV batteries, batteries for light electric vehicles such as e-bikes and scooters, and industrial batteries above 2 kWh. Portable consumer batteries without a digital passport are largely excluded here. It is also important to note what does not belong in this section: the precise chemical composition of the battery is a separate figure, recorded elsewhere in the passport and subject to different requirements than the capacity and power figures. Anyone looking for how that composition is recorded can read more about it on the page on recording battery chemistry. Data on hazardous substances in the battery also form a separate category, distinct from capacity and power data, and can be found on the page on hazardous substances in the battery. The capacity and power data therefore specifically concern the energy performance of the battery as a whole, not what it is made of or what it contains.

Mandatory from 18 February 2027, until then no passport requirement

The obligation to make this data digitally available via the battery passport comes into effect on 18 February 2027. Until that date, there is no obligation to disclose these figures in a digital passport, although manufacturers and importers may choose to do so now. For those importing e-bike or scooter batteries, or placing industrial batteries above 2 kWh on the market, this date is the moment when technical documentation on capacity and power must no longer be confined to a datasheet or manual, but must be linked to the QR code on the battery itself.

Where to start: from nameplate to passport

The practical sequence begins with gathering what already exists: most manufacturers already provide capacity in Ah and power in W or kW on the nameplate or in the product documentation, so the first step is to check whether these figures are unambiguous and current for the specific battery model being imported or traded. The second step is to check whether the power data also cover the conditions required by the regulation, such as performance at different temperatures — this is often not standard in an ordinary datasheet and must then be requested from the manufacturer. The third step is to distinguish this data from the durability data that lies close by, such as expected service life and capacity retention after a certain number of cycles; anyone wanting a more complete picture of this will find it on the page on performance and durability data. Only once these figures are complete and verified is it worthwhile to submit them for inclusion in the passport, because a passport based on incorrect or incomplete source data will need to be amended later. Anyone wanting a broader overview of all the data categories that together make up the passport — not just capacity and power, but also chemistry, safety and recycling — will find that overview on the page on which data must be included in the battery passport.

Set out in Articles 9 and 10 and in Annex XIII

This obligation derives from Articles 9 and 10 of Regulation (EU) 2023/1542 (Battery Regulation), which describe the performance and durability requirements for batteries, including requirements on capacity, power and how these are measured and reported. Annex XIII of the same regulation elaborates this into the specific list of data that must be included in the battery passport, with nominal capacity and power as fixed components thereof. The precise measurement methods and definitions associated with these figures are set out in the articles themselves and in the related technical standards.

Anyone wishing to have this data processed into a functioning passport begins by collecting the technical data sheets of the manufacturer for each battery model, and checks that capacity, power and voltage are recorded unambiguously and completely — this is the submission file with which a passport can actually be compiled and hosted.

What this is based on

The Regulation itself is on EUR-Lex. We refer for each statement; you need not believe us.

What you need to do concretely

What is expected of you

Annex XIII of the Battery Regulation lists capacity and power as fixed components of the data set that must be included in the battery passport. This is not a single figure, but a series of values that together show how much energy a battery can deliver, how that capacity relates to the original value, and how the battery performs under different conditions. The precise performance requirements are set out in Articles 9 and 10 of the regulation, which form the basis for what subsequently ends up in the passport.

Recording nominal capacity

Nominal capacity — usually in ampere-hours or watt-hours — is the starting point. This is the value that the manufacturer established when designing the battery and which serves as a reference for subsequent measurements, such as state of health. For a company with 10 to 100 employees, this mainly means that this value already exists somewhere — in a datasheet, a test report or a declaration of conformity from the cell manufacturer — and that this value must be adopted without room for own interpretation or rounding that is not substantiated.

Including power and load capacity

In addition to capacity, the passport requests data on power: how much energy the battery can deliver or take in per unit of time. For applications such as e-bikes and scooters, this is relevant because power is related to motor control and charging behaviour. In practical terms, this means that an importer needs not only the cell specification, but also data on the battery pack configuration — how cells are connected — because that affects the power delivered.

Showing changes in capacity over time

Annex XIII does not ask for just a snapshot, but also for data that make the development of capacity over time transparent. This directly touches on the question what is the state of health of a battery and why must it be included, because capacity loss is one of the indicators used for it. For a company, this means that there must be a system to store measurements and link them to the passport, not only at delivery but also afterwards.

Documenting test conditions

A capacity or power value without the conditions under which it was measured tells little. Articles 9 and 10 refer to harmonised test standards and methods by which performance is determined. In practice, this means that not only the result of a test is relevant, but also under what conditions (temperature, charging speed, test protocol) that result was obtained — information that is often already in a test report, but is not always carried through to the passport.

Monitoring coherence with other performance data

Capacity and power do not stand alone from other data in the passport. They are related to the data that belong to the question which performance and durability data belong in the passport, such as expected lifespan and sustainability class. For a company, this means that these data cannot be submitted separately without attention to mutual consistency — a capacity value that does not align with the specified lifespan raises questions.

Where things go wrong in practice

A first situation where things go wrong: the nominal capacity stated on the nameplate or in the sales documentation differs from the value in the cell manufacturer's test report, without it being clear which of the two should be the source for the passport.

A second situation: power data are submitted for the individual cell, while the passport concerns the assembled pack. The delivered power of a pack may differ from what a single cell can handle, and this translation is sometimes skipped.

A third situation arises when test conditions are not taken into account. A capacity measured at 25 degrees is placed next to a value determined under different conditions without explanation, making the data in the passport incomparable to what is communicated elsewhere about the same battery.

A fourth situation: with a new batch delivery of the same battery, the old capacity value is simply carried over without checking whether the manufacturer has meanwhile adjusted anything in cell chemistry or configuration. This touches on the question how often must I update the data in the battery passport, because a passport that was correct upon implementation may not be correct after a supplier change.

A fifth situation: capacity data are kept internally for warranty purposes, but never systematically passed on to the party assembling the passport, creating a gap between what the company knows and what the passport shows.

What you can record

The test report or data sheet from the cell manufacturer in which nominal capacity and power have been established, including reference to the test standard used.
An overview of the pack configuration (number of cells, circuit) by which the translation of cell values to pack values can be traced.
The test conditions under which capacity and power were measured, separate from the result itself.
A documented agreement with the manufacturer or supplier about who supplies which measurement value, and in what form — this relates to the broader question which data must be in the battery passport.
A procedure for reviewing capacity data when there is a change of supplier, cell type or batch.
Internal notes on the relationship between capacity value and stated state of health, so that both data do not contradict each other.

This is not legal advice. This page provides general information about the legislation that this platform covers. We do not know your situation. If in doubt about your own case, consult a lawyer or the competent supervisory authority.

Written with AI based on the sources above, checked by a human on 2026-09-05. Is something incorrect? Let us know — corrections take priority.