IEC 61960-3 - Battery Design

Secondary Lithium Cells and Batteries for Portable Applications

IEC 61960-3 is an international standard published by the International Electrotechnical Commission (IEC) that specifies performance tests, designations, markings, dimensions, and other requirements for secondary lithium cells and batteries for portable applications. Unlike IEC 62133-2 (which covers safety), IEC 61960-3 is a performance standard providing manufacturers and purchasers with standardised criteria to compare and characterise portable lithium cells and batteries. It covers prismatic and cylindrical form factors; button and coin cells are addressed in IEC 61960-1.

Published by: International Electrotechnical Commission (IEC)

Current edition: IEC 61960-3:2017 (1st edition as Part 3, February 2017)

Replaces: IEC 61960:2011 (2nd edition, which was a unified standard; Part 3 splits out prismatic/cylindrical cells)

Companion standards: IEC 61960-1:2023 (button/coin cells), IEC 61960-2 (prismatic cells — earlier split edition)

Scope

IEC 61960-3 applies to prismatic and cylindrical secondary lithium single cells and batteries for portable applications. Portable applications comprise hand-held equipment, transportable equipment, and movable equipment including:

Mobile phones, smartphones, and tablets
Laptop and portable computing devices
Power tools, cameras, and consumer electronics
Medical portable devices and wearables

Exclusions: The standard does not cover safety testing (which is addressed by IEC 62133-2 for lithium systems), traction batteries for road vehicles, or stationary/industrial applications.

Key Requirements and Test Methods

Cell Designation and Marking

IEC 61960-3 defines a standardised designation system identifying cell chemistry, shape, dimensions, and terminal type. This allows unambiguous identification of cells in supply chains and procurement documents. Markings must appear on individual cells and battery packs.

Performance Tests

Rated capacity (C/5 and C/2 discharge): measures capacity at defined constant current rates; cells must deliver ≥90% of manufacturer-stated rated capacity at standard temperature (20 °C ± 5 °C)
Charge retention: fully charged cell stored at 20 °C for 28 days; residual capacity must be ≥80% of initial capacity after storage
Capacity after storage (Annex B): cells stored from the date of manufacture at 20 °C for 1 year; capacity recovery after recharge assessed
Recovery charge after complete discharge: cell discharged to cut-off voltage; after recharge, minimum capacity recovery defined
High-temperature performance: discharge at 45 °C — minimum capacity ratio relative to 20 °C performance defined
Low-temperature performance: discharge at −20 °C — minimum capacity ratio relative to 20 °C performance defined
Cycle life: cells cycled using defined charge/discharge protocol; capacity must remain above minimum threshold (typically ≥80% of rated) after 500 cycles or manufacturer-declared cycle count

Dimensions

The standard specifies reference dimensions for standard cylindrical cell formats (e.g., 18650, 21700, 26650) and prismatic cells, with tolerances. An informative annex (Annex A) covers dimensions for cells with laminate film (pouch) cases.

Regional Adoption

International: IEC 61960-3 is widely adopted globally as the reference performance standard for portable Li cells
Europe: adopted as EN 61960-3 / BS EN 61960-3; cited in EU Battery Regulation requirements for performance declaration
Japan/Korea: both markets use national adoptions of IEC 61960-3 for cell performance characterisation in procurement and regulatory submissions

Related Standards

IEC 62133-2 — Safety requirements for portable sealed secondary lithium cells and batteries (the safety counterpart to IEC 61960-3)
UN 38.3 — Transport testing for lithium batteries; required alongside IEC 61960-3 characterisation before shipping cells
EU Battery Regulation — References performance parameters characterised under IEC 61960-3 for LMT and portable battery declarations of conformity
IEC 62619 — Safety requirements for industrial applications; IEC 61960-3 is the performance companion for cells that will be used in industrial systems
IEC 61960-1:2023 — Secondary lithium cells and batteries for portable applications — Part 1: Button and coin cells

Disclaimer: This is not a definitive guide, just an indication and it is important that you always go back to the source for legislation.