IEEE 1725 - Battery Design

IEEE 1725 is an IEEE standard that establishes criteria for design analysis, qualification, quality, and reliability of rechargeable lithium-ion (Li-ion) and Li-ion polymer batteries used in cellular telephone and mobile phone applications. It is published by the Institute of Electrical and Electronics Engineers (IEEE) and is widely referenced by device manufacturers, battery pack suppliers, and certification bodies — most notably through the CTIA Battery Compliance Certification program.

Published by: IEEE (Institute of Electrical and Electronics Engineers)
Current edition: IEEE 1725-2021 (published August 2021)
Replaces: IEEE 1725-2011 — IEEE Standard for Rechargeable Batteries for Cellular Telephones

Scope

IEEE 1725 covers all forms of rechargeable Li-ion cells regardless of chemistry, assembly, and packaging used in host devices such as mobile phones and cellular telephones. The standard addresses battery pack electrical and mechanical construction, packaging technologies, pack- and cell-level charge and discharge controls, and overall system considerations including host device interface requirements.

The standard does not apply to batteries used in electric vehicles, stationary energy storage, or other non-cellular applications. Laptop and tablet battery applications are separately addressed by IEEE 1625.

Key Requirements

Cell design criteria: requirements for qualification, quality, and reliability of the Li-ion cell, covering chemistry, assembly, and packaging
Electrical construction: battery pack construction requirements including contacts, connectors, and protection circuitry
Charge/discharge controls: pack- and cell-level protection against overcharge, over-discharge, over-current, and short circuit
Thermal management: thermal and mechanical considerations to prevent overheating, fire, and mechanical failure
Safety parameters: limits for voltage, current, and temperature agreed between cell manufacturer, pack manufacturer, and host device manufacturer
System compatibility: operating conditions must be set by agreement among cell, pack, and host device suppliers based on cell manufacturer specifications
Separator requirements: the cell separator must maintain physical separation between anode and cathode and provide ion transfer pathways

Certification and Regional Recognition

IEEE 1725 is the technical basis for the CTIA Battery Compliance Certification program, which is used by mobile network operators and device manufacturers in North America to validate Li-ion battery systems used in cellular products. The CTIA program is a system-level scheme covering recognition of battery packs and adapters as subsystems, and certification of complete cellular product systems. Requirements include NRTL (Nationally Recognized Testing Laboratory) certification marking, testing conducted by CTIA-authorised laboratories, and submission of system component details to the CTIA Certification database.

IEEE 1725 is not mandatory under US federal law but is widely required by carriers and operators as a procurement condition. It is primarily applicable in North America; IEC 62133-2 serves an equivalent function in international markets.

Related Standards

IEC 62133-2 — Safety requirements for portable sealed secondary lithium cells and batteries (international equivalent for portable device batteries)
UL 1642 — UL standard for lithium cells and batteries (cell-level safety in North America)
IEEE 1625 — Standard for Rechargeable Batteries for Multi-Cell Mobile Computing Devices (laptops, tablets)

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