Battery Regulation: what applies to an energy storage system?

What changed compared to 2006

The old directive mainly concerned collection, recycling, and disposal. The regulation covers the entire life cycle and sets requirements for the product itself: safety, performance, labeling, origin of raw materials, and information. Furthermore, it applies directly in all member states without national transposition.

Regulation (EU) 2023/1542 dates from July 12, 2023. Directive 2006/66/EC is repealed with effect from August 18, 2025, with a few provisions that still continue. For you, the core is that a battery is now a product with its own conformity requirements. It is no longer primarily a waste issue.

A stationary battery energy storage system has its own definition in this regard. It is an industrial battery with internal storage designed to store electricity from the grid and supply it to the grid. The second variant stores electricity for the end user and supplies it to them. Where or by whom the system is used does not matter for that definition.

The dates that actually apply

The regulation does not have a single effective date but a series of them. The bulk of the provisions have applied since February 18, 2024. These are followed by separate dates for safety documentation, labeling, the battery passport, and due diligence requirements. The latter were postponed by two years in 2025.

Regarding labeling, there is a caveat in the text itself. Article 13 applies from August 18, 2026, or eighteen months after the entry into force of the implementing act containing the harmonized specifications, whichever is later. Therefore, check the status of that implementing act before having your label printed.

Article 12 and the eleven safety parameters

Article 12 requires that since August 18, 2024, your technical documentation demonstrates that the system is safe during normal use. That evidence consists of tests on the safety parameters of Annex V, supplemented by an assessment of risks not listed there.

Annex V lists eleven parameters: thermal shock and cycling test, external short-circuit protection, overcharge protection, over-discharge protection, over-temperature protection, thermal propagation protection, mechanical damage from external influences, internal short-circuit, thermal exposure, fire test, and emission of gases.

Two things are often missed in this regard. Firstly, the parameters only apply insofar as the associated risk can occur in your system under your intended conditions of use, so you must substantiate that scope. Secondly, the regulation requires instructions to mitigate the consequences of a detected risk, for example, in the event of fire or explosion.

CE marking and the conformity assessment

Batteries bear CE marking. The conformity assessment for the requirements from, among others, Article 12 proceeds for series production via Module A (internal production control) or via Module D1 (quality assurance of the production process). For batteries not manufactured in series, Module G also exists, conformity based on unit verification.

The marking is applied before the battery is placed on the market or put into service. If a notified body is involved according to Annex VIII, the identification number of that body follows the CE marking.

Note that a stationary system rarely falls only under the Battery Regulation. Depending on the construction, the Low Voltage Directive, the EMC Directive, and, for grid-connected inverters, additional requirements also play a role. Your declaration must mention all of that legislation.

The battery passport as of February 18, 2027

From February 18, 2027, every industrial battery with a capacity of more than 2 kWh must have an electronic file, the battery passport. This also applies to batteries for light means of transport and for electric vehicle batteries. Almost every stationary storage system falls above that limit.

The passport contains information about the model and about the individual battery, including data resulting from use. Part of it is public, part is only accessible to certain parties. Annex XIII determines which data falls into which category.

The practical challenge lies not in the passport itself, but in your data. Serial numbers, composition, origin, and performance data must be traceable per individual unit. That is a matter for your production registration, not for a document folder.

Due diligence requirements, postponed to 2027

The regulation obliges larger economic operators to have a due diligence policy for the origin of raw materials such as lithium, cobalt, nickel, and natural graphite. That policy must be externally verified. The obligation was supposed to apply from August 18, 2025, but has been postponed by two years to August 18, 2027.

The reason for the postponement was practical. There were still too few recognized verification bodies available to assess the policy. The postponement is established in Regulation (EU) 2025/1561. The content of the requirements has not changed, only the moment they take effect.

Use that time. Those who map out their chain now will only need to have what is already there verified in 2027.

What you should arrange now

Start with Article 12, as that date passed two years ago. Check whether your file contains the safety tests at the system level and whether the exclusion of non-applicable parameters is substantiated in writing. Then look ahead to the battery passport, as that affects your production registration and not just your document folder.

1. Request for each system which safety parameters from Annex V have been tested and at what level: cell, module, or system.
2. Document why a parameter is not applicable. Without substantiation, that is a gap in the file.
3. Check whether your mitigation instructions for fire or explosion are part of the documentation.
4. Determine which other legislation is involved and whether your declaration of conformity mentions all of it.
5. Map out which data you register per individual unit. That determines whether the passport is feasible in 2027.