Overview:

With the rapid increase in the demand for energy storage batteries, the shipment volume has increased significantly, and a large number of related enterprises have entered the energy storage market. In order to improve the image and quality of their products for a strong product competitiveness, and meet the needs of various countries or regions, more and more enterprises began to test as per UL 9540A. To let you better understand this standard, the following is a simple summary for the standard requirements.

A brief description of testing for different level:

UL 9540A divides the test of energy storage products into four levels: cell, module, unit (cabinet), and installation. The purpose, procedure, and requirements of each test are briefly described below.

• Cell testing:

The purpose of cell testing is to collect the basic parameters of cell thermal runaway (such as temperature, gas composition, etc.) and determine the method of thermal runaway;

The process of cell testing: The cell is pretreated to charge and discharge in two cycles according to the manufacturer’s regulations; The cell is placed in a sealed gas collection tank, which is filled with nitrogen; The cell triggers thermal runaway, with methods including heating, acupuncture, overcharge, etc.; After the end of thermal runaway of the cell, the gas in the tank is extracted for gas analysis; Measure explosion limit data according to the composition of gas group information, get the data of heat release rate and explosion pressure.

• Module testing:

It is preliminarily verified that the module design can prevent the cell from spreading to the outside of the module when thermal runaway occurs. In the module stage, the structural design can ensure that the heat spreading does not occur in the module.

The process of module testing: The cell is pretreated to charge and discharge in two cycles according to the manufacturer’s regulations; A cell in the module is operated according to the method of cell testing to trigger thermal runaway; Monitor heat release rate, hydrocarbon chemical content, hydrogen concentration, smoke release concentration and gas composition during heat loss.

• Unit (cabinet) testing:

The unit (cabinet) testing is to verify that heat spread can be controlled in the unit (cabinet) after thermal runaway of the cell. Before the test, the triggering unit and the target unit shall be installed according to the standard requirements, and then the triggering method of the module shall trigger the thermal runaway of the cell; The temperature and heat flux of nearby walls, target unit and triggering unit will be monitored during the test, as well as the gas composition.

• Installation testing

The purpose of the installation testing is to verify whether the corresponding fire control arrangement can control the combustion of the energy storage cabinet after thermal runaway occurs in the installation process. The test installation is the same as the installation at the unit testing. This test is not suitable for outdoor installations.

Extras:

The test requirements of UL 9540A derives from UL 9540, whose purpose is to evaluate the safety of the final product during installation and use and the exemption or relaxation of installation conditions through thermal runaway and heat spread tests(such as increasing the total capacity of energy storage system, reduce the installation distance, etc.). So the user of this report is the department or personnel authorized by the government in the place where the product is installed. Therefore, when conducting this test, the popularity or recognition of the report issuing agency is very important. As an international certification agency, TUV RH has high recognition in both Europe and North America, and is one of the organizations that manufacturers and factories highly trust.