IEC 62660-2 is an international standard published by the International Electrotechnical Commission (IEC) that specifies test procedures for evaluating the reliability and abuse behaviour of secondary lithium-ion cells and cell blocks used for propulsion of electric road vehicles. It establishes a standard classification of test results to support the design of battery systems and battery packs for BEV and HEV applications.
Published by: International Electrotechnical Commission (IEC), Technical Committee 21 — Secondary Cells and Batteries
Current edition: IEC 62660-2:2018 (Edition 2.0, December 2018)
European adoption: EN IEC 62660-2:2019; BS EN IEC 62660-2:2019 (UK)
Replaces: IEC 62660-2:2010 (Edition 1)
Scope
IEC 62660-2 applies to secondary lithium-ion cells and cell blocks used for propulsion in BEV and HEV applications. It covers two categories of testing: reliability tests, which evaluate performance degradation under simulated environmental and operational stresses; and abuse tests, which assess the response of cells to conditions beyond their normal operating limits.
PHEV cells may be evaluated under either the BEV or HEV procedure, as agreed between cell manufacturer and customer. Performance testing (capacity, power, cycle life) is covered separately in IEC 62660-1. Safety requirements are covered in IEC 62660-3.
Key Test Methods
Reliability tests:
- High-temperature storage — Capacity retention measured after storage at elevated temperature to assess calendar aging.
- Temperature cycling — 30 cycles between −40 °C and +85 °C; evaluates resistance to thermal expansion/contraction stresses. Note: the option for temperature cycling with electrical operation was removed in Edition 2.
- Vibration — Random vibration profile applied for 8 hours per axis across all three orthogonal axes; simulates road-induced vibration loads.
- Mechanical shock — 10 half-sinusoidal pulses applied in each of 6 spatial directions; evaluates resistance to handling and collision events.
Abuse tests:
- Crush — Cell compressed mechanically to evaluate the response to deformation; pass/fail based on absence of fire, explosion, and electrolyte leakage.
- External short circuit — Terminals short-circuited via a low-resistance path at defined temperatures; evaluates thermal response.
- Forced discharge — Cell reverse-charged beyond 0 V; procedure clarified in Edition 2.
- Overcharge — Cell charged beyond its maximum voltage specification; test conditions revised in Edition 2.
- High-temperature endurance — Cell subjected to a temperature ramp of 5 K/min to 130 °C, held within ±2 K for 30 minutes; evaluates thermal stability of cell chemistry.
For each test, the standard provides a classification system for describing results (no defect, leakage, rupture, fire, explosion) enabling consistent reporting between manufacturers and system designers.
Regional Adoption
IEC 62660-2:2018 has been adopted in Europe as EN IEC 62660-2:2019 and in the UK as BS EN IEC 62660-2:2019. It is widely referenced in automotive OEM cell qualification requirements. No single jurisdiction mandates the standard directly as a regulatory requirement, but it is commonly specified in procurement and certification programmes for EV traction cells.
Related Standards
- IEC 62660-1 — Performance testing of Li-ion cells for EV propulsion
- IEC 62660-3 — Safety requirements for secondary lithium-ion cells for propulsion of electric road vehicles
- IEC 62619 — Safety requirements for secondary lithium-ion cells and batteries for industrial applications
- UN 38.3 — Transport testing of lithium cells and batteries
- EU Battery Regulation — Regulatory framework for batteries placed on the EU market
Disclaimer: this is not a definitive guide, just an indication and it is important that you always go back to the source for legislation.
References
- IEC 62660-2:2018, IEC Webstore
- IEC 62660-2:2018, Standards and Grid Codes Database
- BS EN IEC 62660-2:2019, EN-Standard.eu