UL 1642 added a test requirement for solid state cells,
UL 1642,

▍What is KC?

Since 25^th Aug., 2008，Korea Ministry of Knowledge Economy (MKE) announced that the National Standard Committee will conduct a new national unified certification mark — named KC mark replacing Korean Certification during the time between Jul. 2009 and Dec. 2010. Electrical Appliances safety certification scheme (KC Certification) is a mandatory and self-regulatory safety confirmation scheme according to Electrical Appliances Safety Control Act, a scheme which certified safety of manufacture and sale. 

The difference between mandatory certification and self-regulatory (voluntary) safety confirmation：

For the safe management of electrical appliances, KC certification is divided into mandatory and self-regulatory  (voluntary) safety certifications as the classification of danger of  product.The subjects of Mandatory certification is applied to electrical appliances which its structures and methods of application may cause serious dangerous results or obstacle such as fire, electric shock. While the subjects of self-regulatory (voluntary) safety certification is applied to electrical appliances which its structures and methods of application can hardly causes serious dangerous results or obstacle such as fire, electric shock. And the danger and obstacle can be prevented by testing the electrical appliances.

▍Who can apply for KC certification：

All legal persons or individuals both at home and abroad who are engaged in manufacturing, assembly, processing of electrical appliance.

▍Scheme and method of safety certification：

Apply for KC certification with product’s model that can be divided into basic model and series model.

In order to clarify model type and design of electrical appliances, an unique product name will be given according to its different function.

▍ KC certification for Lithium battery

1.  KC certification standard for lithium battery：KC62133:2019
2. Product scope of KC certification for lithium battery

A. Secondary lithium batteries for use in portable application or removable devices

B. Cell is not subject to KC certificate whether for sale or assembled in batteries.

C. For batteries used in energy storage device or UPS (uninterruptible power supply), and their power which is greater than 500Wh are beyond the scope.

D. Battery whose volume energy density is lower than 400Wh/L comes into certification scope since 1^st, Apr. 2016.  

▍Why MCM?

● MCM keeps a close cooperation with Korean labs, such as KTR (Korea Testing & Research Institute) and is able to offer the best solutions with high cost performance and Value-added service to clients from the point of lead time, testing process, certification cost.

● KC certification for rechargeable lithium battery can be gained by submitting a CB certificate and convert it into KC certificate. As a CBTL under TÜV Rheinland, MCM can offer reports and certificates which can be applied for conversion of KC certificate directly. And the lead time can be shortened if applying CB and KC at the same time. What’s more, the related price will be more favorable.

At present, most solid state batteries are based on lithium-sulfur batteries. Lithium-sulfur battery has high specific capacity (1672mAh/g) and energy density (2600Wh/kg), which is 5 times that of traditional lithium-ion battery. Therefore, solid state battery is one of the hot-spot of lithium battery. However, the significant changes in the volume of sulfur cathode during the process of delithium/lithium, the dendrite problem of lithium anode and the lack of conductivity of solid electrolyte have hindered the commercialization of sulfur cathode. So for years, researchers have been working on improving the electrolyte and interface of solid state battery.
UL 1642 adds this recommendation with the goal of effectively solving the problems caused by the solid battery (and cell) characteristics and potential risks when in usage. After all, cells containing sulphide electrolytes may release the toxic gas like hydrogen sulphide under some extreme conditions. Therefore, in addition to some routine tests, we also need to measure toxic gas concentration after the tests. Specific test items include: capacity measurement, short circuit, abnormal charge, forced discharge, shock, crush, impact, vibration, heating, temperature cycle, low pressure, combustion jet, and measurement of toxic emissions.The standard GB/T 35590, which covers portable power source, is not included into 3C certification. The main reason may be that GB/T 35590 pays more attention to the performance of the portable power source rather than safety, and the safety requirements are mostly referred to GB 4943.1. While 3C certification is more about ensuring product safety, therefore GB 4943.1 is chosen as the certification standard for portable power source.