On 2026年4月23日，the mandatory provisions concerning BMS sensor modules under the EU New Battery Regulation (EU 2023/1542) officially came into effect, clearly requiring that the voltage, current, temperature and pressure sensors integrated into all power battery management systems entering the EU market must support a real-time SOC dynamic calibration interface and pass verification under Annex D of EN IEC 62619:2026. This requirement directly affects type certification and customs clearance compliance for Chinese BMS sensor exporters, and products that have not completed the required adaptation may be denied entry by EU customs.

Event Overview

On 2026年4月23日，the mandatory provisions for sensor modules under the EU New Battery Regulation (EU 2023/1542) were officially implemented. Under these provisions, all voltage, current, temperature and pressure sensors integrated into battery management systems (BMS) sold to the EU market must have a real-time SOC (State of Charge) dynamic calibration interface function and must pass the verification procedures specified in Annex D of EN IEC 62619:2026. This requirement has become a prerequisite for product market access and is directly linked to CE marking type certification and EU customs clearance procedures.

Which market segments will be affected

Direct trading enterprises：Mainly refers to companies exporting BMS sensor modules or complete BMS units containing sensors to the EU under their own brands or through OEM arrangements. As the new regulation lists the SOC calibration interface as a mandatory functional item, existing inventory and in-transit orders that have not completed firmware upgrades or hardware modifications may face the risk of return shipment, recall or customs clearance delays; the impact will be reflected in a higher rejection rate during export document review, longer certification cycles and increased compliance costs.

Processing and manufacturing enterprises：Including BMS main control board SMT factories, sensor PCBA contract manufacturers, and packaging and testing plants. Their production and delivery must simultaneously meet the newly added interface definitions (such as standardized communication protocols, calibration trigger pins, and timing response requirements), otherwise downstream customer acceptance may fail; the impact will be reflected in production line fixture adjustments, rework of test jigs, BOM changes and extended first article confirmation cycles.

Supply chain service enterprises：Covering third-party organizations that provide export companies with CE certification consulting, EMC/safety testing, technical documentation preparation and EU Authorized Representative (AR) services. After implementation of the new regulation, their test report templates, technical documentation structures (especially Chapter 8, "Software Interface Description") and Declaration of Conformity (DoC) content must all be updated in accordance with Annex D of EN IEC 62619:2026; the impact will be reflected in the need to readjust existing service processes, and some organizations have not yet published corresponding lists of verification capabilities.

What key points should relevant enterprises or practitioners focus on, and how should they respond at present

Pay attention to the release timing of the official interpretive documents for Annex D of EN IEC 62619:2026

Although the standard text has already been published, key parameters in Annex D such as "electrical characteristics of the calibration interface", "communication frame format" and "minimum response time" still lack supporting application guidelines. Enterprises should continue to track the CENELEC official website and European Commission announcements to avoid finalizing hardware designs based on non-authoritative interpretations.

Differentiate the compliance paths for already certified models and newly declared models

For BMS sensor products that completed CE certification before 2026年4月23日 and are still within their validity period, whether the new regulation can be met through supplemental technical documentation rather than re-certification is still awaiting a unified clarification from EU Notified Bodies (NB). Enterprises should not assume that "old certificates remain valid" by default, and should proactively obtain written confirmation from their cooperating NB regarding the applicability of transitional policies.

Prioritize interface compatibility verification for main export models

Given that 6月 is the practical adaptation deadline window for most enterprises, it is recommended to focus on the 3–5 core sensor models that account for more than 70% of annual export volume, and prioritize confirmation of hardware interface definitions, development of firmware calibration logic and third-party pre-testing, so as to avoid resource dispersion and delivery delays caused by a full-scale rollout.

Simultaneously update interface descriptions and user manual sections in technical documentation

Annex D of EN IEC 62619:2026 clearly requires the provision of three categories of technical information: "functional description of the calibration interface, access permission settings, and exception handling mechanisms". Enterprises need to present these as separate chapters in product manuals, safety compliance manuals and CE technical documentation, and cannot replace them solely with code comments or internal design documents.

Editorial Viewpoint / Industry Observation

From an industry perspective, the implementation of this provision is more like a strong regulatory signal than a simple result of technical upgrading. It indicates that the EU is extending battery system-level functional safety requirements downward into sensor-layer hardware interface specifications, reflecting its intention to control the verifiability of the entire BMS chain. From an analytical perspective, this requirement will not change the overall BMS architecture in the short term, but it will significantly raise the threshold for low- and mid-end sensor modules entering the EU market. What deserves more attention at present is whether similar interface requirements will extend to sensor units related to SOH (State of Health) or SOP (State of Power) — this needs to be judged in conjunction with the subsequent work plan of the EU battery regulatory authority (EBRA).

Conclusion：
This new regulation is not an isolated technical adjustment, but a landmark node in the deeper implementation of the EU New Battery Regulation. It means that Chinese BMS sensor export compliance has moved from the stage of "electrical safety + environmental marking" into a new stage of "verifiable functional interfaces". At present, it is more appropriate to understand it as an adaptive adjustment to definite rules rather than a warning of uncertain risks; enterprises should take the standard text as the sole benchmark, focus on interface implementation and documentation completeness, and avoid over-interpretation or a wait-and-see approach.

Information source note：
Main sources: original text of EU Regulation EU 2023/1542, EN IEC 62619:2026 standard text (including Annex D), and CENELEC official website announcements (updated in 2026年4月).
Areas requiring continued observation: detailed transitional arrangements by EU Notified Bodies (NB) for already certified models, and the release timing of the supporting application guidelines for Annex D of EN IEC 62619:2026.