IEC 61951-1:2017

Overview

IEC 61951-1:2017 is an international standard published by the International Electrotechnical Commission (IEC) that specifies requirements for secondary sealed nickel-cadmium (Ni-Cd) cells and batteries used in portable applications. This standard addresses the marking, designation, dimensions, testing, and performance criteria for small prismatic, cylindrical, and button-type Ni-Cd cells and batteries. These secondary cells are designed to operate with alkaline or other non-acid electrolytes and can be used in any orientation, making them versatile for numerous portable devices.

The 2017 edition, supplemented by the 2023 amendment, introduces significant technical updates, including the addition of battery types, updated dimensional figures, and revised contact marking details to improve clarity and interchangeability.

Key Topics

• Cell and Battery Designation and Marking: The standard defines precise marking and designation systems for prismatic, cylindrical, and button cells to ensure consistency and traceability.

• Dimensions: It specifies exact dimensions for jacketed cylindrical, small prismatic, and button cells, including dimensionally interchangeable cells with primary cells. This ensures compatibility and facilitates replacement in portable devices.

• Electrical Testing Procedures: IEC 61951-1 includes comprehensive tests such as:

  • Charging and discharging performance at standard (+20 °C) and low temperatures (-18 °C)
  • Charge retention and endurance cycle tests
  • Overcharge tests and safety device operation, including pressure relief mechanisms
  • Internal resistance measurements (AC and DC)
  • Trickle charge acceptance for specific cell types

• Mechanical and Safety Requirements: The standard mandates mechanical tests to guarantee the reliability and safety of Ni-Cd cells under various conditions.

• Type Approval and Batch Acceptance: Procedures for type approval and batch acceptance tests are outlined to verify compliance before market release, ensuring quality and reliability.

Applications

IEC 61951-1:2017 is critical for manufacturers and users of secondary nickel-cadmium cells and batteries in a wide range of portable electronic devices, including:

• Portable communication devices: Radios, walkie-talkies, and early mobile phones where reliable rechargeable power sources are needed.

• Medical devices: Portables such as hearing aids and diagnostic instruments benefiting from sealed, rechargeable Ni-Cd batteries.

• Power tools and consumer electronics: Devices requiring dependable and lightweight power units capable of multi-orientation use.

• Emergency and backup power: Systems where reliable rechargeable cells play a role in ensuring uninterrupted operation.

By following IEC 61951-1, manufacturers ensure that Ni-Cd cells and batteries meet international performance, safety, and interchangeability standards, improving user confidence and product longevity.

Related Standards

Organizations and engineers working with IEC 61951-1 may also need to consider related IEC standards and technical guidelines that address other battery chemistries or general battery safety and testing protocols, such as:

• IEC 62133: Safety requirements for rechargeable batteries containing alkaline or other non-acid electrolytes, focusing on portable sealed secondary cells and batteries.

• IEC 61951-2: Complementary part of IEC 61951 covering nickel-metal hydride batteries - another common rechargeable technology for portable applications.

• IEC 60086 series: Primary batteries standards, which complement secondary battery standards by defining primary cell dimensions and performances.

• IEC 60335-1: Safety of electrical appliances includes requirements that may affect battery-powered portable products.

Compliance with IEC 61951-1:2017 ensures that nickel-cadmium cells and batteries meet stringent international quality benchmarks, promoting safety, interoperability, and performance across global markets for portable electronic applications.