Lithium battery testing standard: GB 31241-2022 Safety Technical Specification for lithium ion batteries and batteries for porta

Lithium battery testing standard: GB 31241-2022 Safety Technical Specification for lithium ion batteries and batteries for portable electronic devices.

It was officially implemented on January 1, 2024 that the new lithium battery testing standard GB 31241-2022, "Safety Specifications for Portable Electronic Lithium-ion Batteries and Battery Packs," was released on December 29, 2022. 18650 manufacture Lithium-ion battery industry growth and sustainability depend on the formulation, promulgation, and implementation of relevant safety standards.

During the transportation, storage, usage, and recycling of lithium-ion batteries, various external factors such as high temperatures, overcharging, overdischarging, and short circuits can lead to safety issues such as leakage, fire, or even explosions. In order to ensure the safety of these batteries and accumulators for portable electronic products, GB 31241-2022 has been established as a technical specification. This document outlines the fundamental principles that must be followed in the design and production of lithium-ion batteries to guarantee their safety. It is important to keep in mind that this document solely focuses on essential safety requirements in order to protect individuals and property, and does not address performance or functional characteristics.

In the future, research and development of information technology and processes will require the revision of this document. Hazards associated with lithium-ion power batteries and battery packs are as follows:

A leak can cause chemical corrosion on the human body or result in a failure of the internal insulation of battery-powered electronics.

Electric shock, fire, etc., are possible risks:

Fire, which burns the body directly or poses a fire hazard to battery-powered electronic devices; Explosion, which causes direct injury to the body or damage to a device;

- Overheating, resulting in direct burns to the human body, reduced insulation levels or safety component performance, or the combustion of flammable liquids. Under the action of shell damage, internal or external stresses may lead to leakage. Thermal runaway may result in fire and explosion inside the battery. Short circuits inside the battery and strong oxidation reactions could lead to thermal runaway.

Follow these priorities when selecting an instructional design research approach for batteries or battery packs;

Prioritize the development of materials with high safety, and avoid materials that are prone to thermal runaway in the course of enterprise use;

The second step is to design protective devices to reduce or eliminate danger, such as installing protective devices, if the above principles cannot be implemented;

It is also necessary to mark the remaining hazards if the above measures do not completely prevent hazards from occurring.

Describe the measures in detail.

GB 31241-2022 "Portable electronic lithium-ion batteries and batteries, Safety Technical Specifications" specifies the following safety test items for batteries:

Low pressure 7.1

Battery should not fire, explode, or leak. Specific analysis test research methods can be used in accordance with the relevant laws in GB/T 2423.21.

The temperature cycle is described in section 7.2

Increase the temperature of the test chamber to 72 degrees Celsius + 2 degrees Celsius and maintain it for 6 hours; b) Reduce the temperature of the test chamber to -40 degrees Celsius + 2 degrees Celsius and maintain it for 6 hours; c) Repeat steps a) to B) 10 times;

Store at room temperature for at least 6 hours at 20 °C to 5 °C.

According to Figure 3, the conversion time between each two temperatures during the test should not exceed 30 minutes. The specific test methods should be carried out in accordance with GB/T 2423.22.

Vibrations

Each direction has 12 cycles, with a total cycle time of 3 hours.

We analyze cylindrical and button batteries according to their axial and radial development directions, and square and flexible packaging batteries according to three aspects of mutual vertical direction information.

GB/T 2423.10 specifies the specific test methods to be used. The battery must not catch fire, explode, or leak liquid.

Impact of acceleration

The fully charged battery was fixed on the shock table to carry out the half-sinusoidal pulse shock test. A battery is subjected to three accelerated shock tests in each direction for a duration of 6ms and 1ms. The minimum average acceleration is 75g, the peak acceleration is 150g, and the pulse duration is 6ms and 1ms.

Cylindrical and button-shaped batteries were tested axially and radially, while square and flexible pack batteries were tested vertically.

GB/u002FT 2423.5 specifies specific test methods.

Fall 7.5

It falls from a height of 1m and falls free fall onto a concrete slab in China after the battery has been fully charged according to the test and research method described in 4.5.1.

On the cylinder and button batteries, four drip tests were conducted, one drop on each end face, two drops on the cylinder face, and one drop on each end face on the square and flexible packaging batteries, a total of six drip tests.

There should be no risk of the battery catching fire or exploding.

Extrusion 7.6

Using the test method specified in 451, the battery is placed on two planes and squeezed vertically in the direction of the dry plate after it has been charged.

In order to extrude the battery, 13.0 KN0.78 KN pressure was applied between the two plates. The battery is extruded at 0.1 mm/s. Once the squeeze test reaches its maximum pressure or the battery voltage drops by one-third, the test can be stopped. The battery should be protected from external short circuits during the test.

Extruded onto a wide surface of the battery, the vertical axis of the half cylinder crosses the center and is perpendicular to the pole lug direction. The semi-cylinder's length should exceed the battery's length.

The extrusion pressure should reach the extrusion pressure corresponding to the width of the flexible packaging battery in Table 10, then be cut off.

One sample was squeeze tested. The time interval between the extrusion reaching the cutoff state and the extrusion device stopping should not exceed 100ms during the extrusion process.

Impact 7.7

When conducting an impact test, the cylindrical battery's vertical axis must align with the heavy object's surface. The metal bar should be positioned perpendicularly to the battery's vertical axis and parallel to the impact surface. As for square batteries, only wide surfaces are used for the culture impact strength test. To analyze impact resistance, a metal rod is passed through a center for treating battery materials. Each sample undergoes a single large-scale impact test.

It is important that the battery does not catch fire or explode.

Batteries in flexible packaging are not covered in this article.

Abuse of heat

Charge the battery per 451, then place it in the test chamber. Heat the laboratory at a rate of 5 °C/MIN + 2 °C/MIN, while maintaining a constant temperature of 130 °C + 2 °C for 30 minutes.

There should be no fire or explosion from the battery.

Combustion Injection 7.9

Once the battery has been fully charged using the designated test and research method in 4.5.1, it is positioned on the steel wire mesh of the designated test equipment (C2 in Appendix C). In case of repeated slipping during the testing process, a single wire may be utilized to secure the battery sample onto the wire mesh. However, if no such slipping occurs, bundling of the battery is unnecessary. The battery should then be heated with a flame until one of three different scenarios occur, which will be analyzed as follows:

Explosion of a battery;

b) The battery is completely burnt;

If the battery does not catch fire or explode, continue heating for 30 minutes.

Components (except dust products) or the entire battery should not penetrate the aluminum mesh after testing.

relevant safety standards Electric shock

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