do I need to update the passport if I repair or modify a battery

Repair or conversion requires a passport update

Yes, when a battery is repaired, has cells replaced or is converted for a new application, the information in the passport must be adjusted accordingly. The passport is intended as a representation of the current condition of the battery, not as a snapshot from the moment of sale. Regulation (EU) 2023/1542 (batteries regulation) explicitly states in article 14 that information on the condition and expected service life must be part of what the passport contains — and that condition changes as soon as cells are replaced, a new cell pack is installed, or the battery is assigned a different purpose than it was originally made for.

Who this applies to and who it does not

This is particularly relevant for batteries that get a second life: an industrial battery that is reassigned to stationary storage after use, an e-bike battery whose cell pack is replaced, or a pack that is converted for a different vehicle or device. Anyone who puts such a battery on the market after repair, preparation for reuse or reassignment falls under the provisions described in articles 73 and 45 of the batteries regulation for market actors placing this type of battery on the market.

It does not apply to routine maintenance that does not alter the properties of the battery, such as a firmware update of the battery management system or replacement of a housing without the cells or cell chemistry changing. It concerns interventions that actually alter the composition, capacity, origin of parts or intended purpose of the battery — that is the moment when the information in the passport no longer corresponds to the actual condition of the battery.

From 18 February 2027, just like the rest of the passport obligation

The obligation to maintain a passport applies from 18 February 2027, as laid down in article 77 of the batteries regulation. Until that date there is no legal obligation to maintain or update a passport, simply because the passport is not yet mandatory. For those already carrying out repairs or conversions on batteries that will be put on the market after that date, it is advisable to already keep track of which parts have been replaced and when — that information will later be needed to correctly update the passport, and is often harder to reconstruct afterwards than if it is recorded immediately.

How to handle a passport update after repair or conversion

In the event of repair or conversion, the first step is to document what has actually changed: which cells have been replaced, from which supplier they come, and whether the capacity or chemistry has been altered. This is the same information that was also needed when the passport was originally compiled, and what data must I request from my battery supplier describes what is relevant for this — that overview can also be used as a checklist during a repair, because in practice replacement parts often come from a different supplier than the original cells.

Next, it is important to determine whether the repair or conversion was carried out by the party managing the passport, or by a third party such as a repair service. If another company performs the physical work, the data on that work must still reach the passport manager so the passport can be updated. This is effectively a supply matter like any other battery data: How do I record the supply of passport data in my purchase contract describes how such arrangements can be documented, and the same approach can be applied to agreements with a repair service or converter.

Subsequently, it is important to verify the new data before it is entered into the passport — especially when replacing cells, because the origin and specifications of those must be as accurate as the original composition. Anyone who is unsure whether the data provided for a replacement part is correct can find in How do I verify that my supplier's data is correct an approach that is useful for this purpose.

Finally: if the battery is sold or put back on the market after the intervention — for example as a refurbished product or for repurposing — then the product passport that applies to that sale is the updated passport, not the original one. The purchaser of that battery is entitled to information that reflects the actual condition of the battery, and that is precisely what Article 14 aims at.

The basis: Article 14, Article 73 and Article 45 of the Battery Regulation

The obligation to include condition and expected lifespan in the passport is laid down in Article 14 of Regulation (EU) 2023/1542. For batteries that are repaired, prepared for reuse or repurposed, Article 73 and Article 45 of the same regulation describe the position of the market actor trading in such batteries. Article 77 of the regulation contains the general provision on the battery passport and the date on which the obligation takes effect.

For those already dealing with battery repair or conversion, the best approach is to record every change to cells or composition as it occurs — this prevents information from later being missing about interventions that were carried out some time ago, when the passport is actually updated.