Behind every CE-marked battery sits a technical construction file. Annex VIII of Regulation (EU) 2023/1542 defines what it must contain, and Articles 39 and 42 require manufacturer and importer to keep it available for ten years. Auditors do not test the battery first — they read the file first. This paper assembles an audit-ready documentation pack for a nickel-metal hydride (NiMH) cell or pack family.
A complete file contains eight blocks. (1) General description: model range, variants, category classification with rationale, rated electrical characteristics and intended use. (2) Design information: drawings of cells, packs, welds and protection circuits, bill of materials split into homogeneous materials, and component/software specifications. (3) Applied standards and specifications: IEC/EN 61951-1/-2 for NiMH cells and batteries, IEC 62133-1 for safety, the IEC 62321 series for substance determination, UN Manual of Tests and Criteria 38.3 for transport, plus any customer or device standards. (4) Test reports and results demonstrating each applicable requirement: Annex I substances, Annex III/IV performance and durability, Annex V safety for stationary systems. (5) Risk assessment and mitigation records. (6) Production-control procedures ensuring series consistency. (7) Labels, markings and instructions per Article 13. (8) The EU Declaration of Conformity and certificates from any notified body involved.
A report must identify the tested sample by lot and date, cite the method standard and edition, state the laboratory's accreditation (ISO/IEC 17025 scope), give detection limits and uncertainty, and reach an explicit pass/fail conclusion against the Regulation's threshold. For NiMH substance evidence this means IEC 62321-4/-5 ICP results for Hg, Cd and Pb against the 5/20/100 ppm limits, IEC 62321-7 for hexavalent chromium where relevant, and REACH targeted tests for sleeves and electronics. Safety evidence follows IEC 62133-1 (nickel systems): expected-use and reasonably foreseeable-misuse tests including continuous charging, external short, forced discharge, mechanical crush and thermal exposure. Performance evidence follows IEC 61951-2 with the exact charge/discharge regime stated. Internal factory reports supplement but do not replace accredited third-party reports for the conformity file.
The risk file identifies hazards across the lifecycle — internal and external short, reverse charging, overcharge, thermal exposure, mechanical abuse, transport damage, end-of-life handling — rates severity and likelihood, and links each risk to a design control (current-limiting PTC, thermal fuse, vent design, cell matching), a test and a user instruction. Production control then guarantees the design intent survives series manufacturing: incoming-material inspection with certificates, cell matching bands, weld-strength sampling, protection-circuit function tests, charge-discharge aging, lot traceability and non-conforming-product control. The auditor follows the chain hazard → control → test → production check; a broken link fails the file even if the product is sound.
The EU Declaration of Conformity follows the Annex IX model and is signed by a named, titled person; it is kept for ten years after the last unit is placed, translated per member state, and issued per model family with batch coverage stated. Article 13 label artwork, user safety instructions and end-of-life guidance are filed in the same language set. The ten-year retention clock runs per batch, so a controlled document register with issue dates, owners and superseded versions is essential; auditors reject loose folders of undated PDFs because change history cannot be reconstructed.
Best practice is a document matrix: one row per legal requirement, columns for the standard clause, the evidence document, its issue date, validity period and owner. Candidate-list updates, standard revisions (watch the IEC 61951 and 62133 amendment cycles), supplier changes and design tweaks each trigger a re-issue; the matrix makes the trigger automatic. A supplier who maintains this system answers an importer's 50-line questionnaire in a day because every answer points to a controlled document rather than a memory.
Weijiang Power ships each NiMH family with a structured Annex VIII file: description and classification, drawings and BOM, accredited IEC 61951/62133-1/62321 and UN 38.3 reports, hazard-to-control risk file, production-control records, Article 13 artwork and a signed Annex IX Declaration. Request our technical-file index and we will map your customer's questionnaire line by line to controlled documents, with issue dates and validity periods visible.
