New Methods of Triggering Thermal Run Away,
Run Away,

▍Certification Overview

Standards and Certification Document

Test standard: GB31241-2014: Lithium ion cells and batteries used in portable electronic equipment―Safety requirements
Certification document: CQC11-464112-2015: Secondary Battery and Battery Pack Safety Certification Rules for Portable Electronic Devices

Background and Date of implementation

1. GB31241-2014 was published on December 5^th, 2014;

2. GB31241-2014 was mandatorily implemented on August 1^st, 2015. ;

3. On October 15th, 2015, Certification and Accreditation Administration issued a technical resolution on additional testing standard GB31241 for key component “battery” of the audio and video equipment, information technology equipment and telecom terminal equipment. The resolution stipulates that the lithium batteries used in the above products need to be randomly tested as per GB31241-2014, or obtain a separate certification. 

Note: GB 31241-2014 is a national compulsory standard. All the lithium battery products sold in China shall conform to GB31241 standard. This standard will be used in new sampling schemes for national, provincial and local random inspection.

▍Scope of Certification

GB31241-2014 Lithium ion cells and batteries used in portable electronic equipment―Safety requirements
Certification documents is mainly for mobile electronic products that are scheduled to be less than 18kg and can be often carried by users. The main examples are as follows. The portable electronic products listed below do not include all products, so products not listed are not necessarily outside the scope of this standard.

Wearable equipment: Lithium-ion batteries and battery packs used in equipment need to meet standard requirements.

▍Why MCM?

● Qualification recognition: MCM is a CQC accredited contract laboratory and a CESI accredited laboratory. The test report issued can be directly applied for CQC or CESI certificate;

● Technical support: MCM has ample GB31241 testing equipment and is equipped with more than 10 professional technicians to conduct in-depth research on testing technology, certification, factory audit and other processes, which can provide more accurate and customized GB 31241 certification services for global clients.

With more accident caused by lithium-ion battery happens, People are more concerned about battery thermal run away, as the thermal run away occurring in one cell may spread heat to other cells, leading to shut-down of the whole battery system.
Traditionally we will trigger thermal run away by heating, pinning or overcharging during tests. However, these methods can neither control thermal runaway in a specified cell, nor can they easily be implemented during tests of battery systems. Recently people are developing new method to trigger thermal runaway. The Propagation test in new IEC 62619: 2022 is an example, and it is estimated that this method will be a wide use in the future. This article is to introduce some new methods that are under research.
Laser radiation is to heat a small area with high energy laser pulse. The heat will be conducted inside the material. Laser radiation is widely used in the areas of material processing, like welding, connecting and cutting. Commonly there are kinds of laser as follows:
Having a CT scan on the not triggered cell, it can be found that there’s no structural influence except for the hole on the surface. It means laser is directional, and high-power, and the heating area is precise. Therefore laser is a good way for testing. We can control the variable, and calculate the input and output energy accurately. Meanwhile laser has the advantages of heating and pinning, like fast heating, and more controllable. Laser has more advantages like: