BS EN 50342-6-2025 PDF

Full title and description

BS EN 50342-6:2025 — Lead‑acid starter batteries — Part 6: Batteries for micro‑cycle applications. This national adoption of EN 50342‑6:2025 specifies definitions, identification, test methods (including micro‑hybrid cycling and dynamic charge acceptance), performance levels and marking for 12 V (and 6 V‑equivalent) lead‑acid starter batteries intended for Start‑Stop / micro‑hybrid vehicle use.

Abstract

This standard defines test procedures and performance criteria that allow battery manufacturers, OEMs and test houses to assess whether lead‑acid starter batteries can reliably perform engine cranking while withstanding frequent micro‑cycle demands (Start‑Stop and regenerative‑braking scenarios). Key test methods include the Micro‑Hybrid Test (MHT), Dynamic Charge Acceptance (DCA) and endurance cycling sequences; the document supplements EN 50342‑1 (general requirements) and provides marking rules for micro‑cycle performance classes.

General information

• Status: Current / definitive (EN edition adopted as a national BS).
• Publication date: EN edition approved by CENELEC 23 June 2025; published as BS EN 50342‑6:2025 (national adoption) in August 2025 (BS publication date recorded 11 August 2025).
• Publisher: European text published under CENELEC (EN 50342‑6:2025); national adoption published by BSI as BS EN 50342‑6:2025.
• ICS / categories: 29.220.20 — Acid secondary cells and batteries.
• Edition / version: 2025 edition (replaces EN 50342‑6:2015 and its A1 amendment).
• Number of pages: ~32 pages for the definitive BS/EN text (national copies and tracked‑change versions may vary in page count).

Scope

The standard applies to lead‑acid starter batteries with a nominal voltage of 12 V (and 6 V batteries by halving voltages where indicated) intended primarily for engine starting, lighting and auxiliary functions in vehicles that employ Start‑Stop / micro‑hybrid strategies and/or regenerative energy recovery. It covers EFB (enhanced flooded) variants delivered dry‑charged where referenced to EN 50342‑1 and excludes batteries intended for other non‑micro‑cycle applications; applicability to certain heavy‑vehicle batteries (EN 50342‑4) is noted as under consideration.

Key topics and requirements

• Micro‑Hybrid Test (MHT): procedure and acceptance criteria to simulate repeated engine off/on micro‑cycles typical of Start‑Stop operation.
• Dynamic Charge Acceptance (DCA): measurement of a battery’s ability to accept rapid charge pulses (important for regenerative braking and short charging intervals).
• Endurance cycling and depth‑of‑discharge regimes: defined cycles and limits to evaluate cycle life under micro‑cycle duty.
• General requirements: labelling, identification, sampling, test equipment capability and standardized test sequences (clauses on measurement syntax and equipment).
• Performance classes and marking: DCA and micro‑cycle performance levels (classification and marking rules for product information).
• Reference to EN 50342‑1: batteries must also meet the general functional tests of the EN 50342 series.

Typical use and users

Primary users are battery manufacturers and designers, automotive OEMs specifying battery duty for Start‑Stop/micro‑hybrid vehicles, independent test laboratories performing EN compliance testing, certification bodies, remanufacturers and fleet engineers evaluating battery choice for vehicles with frequent stop/start cycles or regenerative braking. The standard is used to set product development targets, acceptance criteria for procurement and to support marketing claims about Start‑Stop suitability.

Related standards

EN 50342‑1 (general requirements for lead‑acid starter batteries), EN 50342‑2 (dimensions and terminal arrangements), EN 50342‑4 (batteries for heavy vehicles) and earlier EN 50342‑6 editions/amendments (2015 and A1:2019) are directly related. The EN 50342 series should be considered together when specifying or testing starter batteries.

Keywords

Lead‑acid, starter battery, micro‑cycle, Start‑Stop, dynamic charge acceptance (DCA), micro‑hybrid test (MHT), EN 50342, BS EN, battery testing, EFB, cycle life, automotive batteries.

FAQ

Q: What is this standard?

A: BS EN 50342‑6:2025 is the British adoption of the European standard EN 50342‑6:2025 that specifies tests and performance levels for lead‑acid starter batteries designed for micro‑cycle (Start‑Stop / micro‑hybrid) vehicle applications.

Q: What does it cover?

A: It covers scope, definitions, sampling, test equipment requirements, test sequences (including the Micro‑Hybrid Test and Dynamic Charge Acceptance), endurance cycling procedures, performance classification and marking for 12 V (and 6 V‑equivalent) lead‑acid starter batteries used in micro‑cycle applications.

Q: Who typically uses it?

A: Battery manufacturers, automotive OEM engineers, independent test laboratories, certification bodies, remanufacturers and fleet/purchasing managers specifying batteries for Start‑Stop or regenerative‑braking vehicles.

Q: Is it current or superseded?

A: The 2025 edition is the current edition and replaces the 2015 edition and its A1 amendment; national adoptions such as BS EN 50342‑6:2025 provide the definitive 2025 text for the UK market. Check your national standards body for the official national publication date and status.

Q: Is it part of a series?

A: Yes — it is part of the EN 50342 series for lead‑acid starter batteries (EN 50342‑1, ‑2, ‑4, etc.); EN 50342‑1 contains general requirements that apply across the series.

Q: What are the key keywords?

A: Lead‑acid, starter battery, micro‑cycle, Start‑Stop, DCA, micro‑hybrid, EN 50342, battery testing, EFB.