There are more cases of lithium-ion battery products due to safety concerns. The operation and high energy density of Li will pose a major challenge to the safety of lithium-ion batteries. At present, research, research methods and standards for the safety performance of lithium-ion batteries, especially the safety risks that may be caused by some microstructural defects that can be caused, back behind the development of lithium-ion battery technology, and systems analysis and evaluation techniques. The requirements for performance evaluation of lithium-ion batteries have not yet been met. For this reason, this article summarizes and analyses some representative values.
- Introduction to Battery Safety Performance Testing Standards
At present, the widely used international standard is the International Electro technical Commission (IEC) lithium-ion battery standard. According to their respective needs, the International Air Transport Association (IATA), the United Nations Committee of Experts on the Transport of Dangerous Goods and the International Civil Aviation Organization (ICAO) have also formulated safety standards relevant to the transport of lithium-ion batteries and have been widely used. In addition, safety standards for lithium-ion batteries developed by some countries and organizations, such as Underwriters Laboratories (UL), American Institute of Electrical and Electronic Engineers (IEEE), and Japan National Bureau of Standards (JIS), also great opportunity. Influence the test results of these principles are similar, but the test conditions are different. There are four international standards that are widely used and highly influential. The United Nations Tests and Standards Manual (UN 38.3) for the transport of dangerous goods and IEC62281: 2012 “Safety of Primary Lithium Batteries and Batteries and Lithium Batteries in Transport” are both focused on safety research and the storage of lithium. -ion battery in travel, mainly aiming at the simulation test of the external environment and mechanical vibration of lithium-ion battery during travel, including the simulation of surface 8 requirements for temperature test, vibration, shock, external shock, overcharge and release pressure. During the test, the battery will ensure that the package does not fall, rewrite, and lose weight, break, stop, short circuit, crack, explosion and fire.
UL1642: 2009 lithium batteries are applicable to primary (non-dischargeable) and secondary (dischargeable) lithium batteries used as electricity in products. The purpose of the standard is to reduce the risk of ignition or explosion of lithium batteries when using this product. Standard battery electrical performance tests include short circuit tests, negative load tests and forced discharge tests; Vibration testing, impact testing and mechanical testing; Environmental testing includes thermal cycle testing of air pollution, high-resolution imaging testing and projectile testing. This test requires that the tested battery is free from fire, explosion, water leakage, exhaust and combustion during the test and the packaging is not broken.
Standard IEEE1625:2008 for portable batteries for portable computers and standard IEEE1725:2006 for rechargeable batteries for mobile phones establish uniform standards for the design, manufacture and development of batteries for computers and mobile phones, mainly related to electronics, physical processes, chemical synthesis, quality control flow processes and packaging technology. Compared to other battery standards, which often pay special attention to batteries or batteries, the above standards carefully consider the components of cells, batteries, housings, power tools, consumers and environment. These two standards focus on the design and process, and do not show much about the subsequent use of the battery, especially storage.
- Targeted analysis of current standards
The main principles can now be summarized in the following categories:
2.1 It is mainly for external environment and mechanical vibration during transportation
According to UN38.3, IEC62281: 2012 and others, the dangers of lithium-ion batteries can occur during transportation through tests such as high altitude simulation, temperature tests, vibration, shock, external short circuit and complex, which means less safety problems during summer. The use of lithium-ion batteries.
2.2 Mainly for design and manufacturing process
Such as IEEE1625, IEEE1725, etc. Using IEEE1725 as an example, the standard divides the lithium-ion battery system of mobile phones into four parts, namely the battery cell, the host and the battery charger. It fully and clearly requires the design, equipment, production process, and complete product testing and testing of the cell, to provide a reliable and tested guarantee for the safety of the cell and even mobile phones and others product communication. The above standards focus on the design and production process of the battery and do not include many safety concerns in the use of lithium-ion batteries. In these IEEE lithium-ion battery standards, due to the strict importance of lithium-ion battery design and manufacturing and various components, the range of applications is limited to a certain extent.
2.3 It focuses on the electrical performance and safety of lithium-ion batteries
According to UL1642. From short circuit, negative load, forced discharge test, extrusion, impact, impact, vibration, thermal pollution, thermal cycling, high simulation test, projectile and other test items, lithium-ion battery should be tested for fire, explosion, water resistance, gas, explosion and packaging during the test. Comparing the two types of regulations above, the main regulations are the safety of lithium-ion batteries, and pay more attention to the safety of batteries caused by heat. However, the basis for the case is hard together. Only the explosion, fire, smoke, leakage, explosion and deformation of the tested battery can distinguish the bad batteries to identify the potential danger.
- Conclusion
Safety performance has been an important feature of lithium ion batteries and another major factor limiting lithium ion battery applications is cost. Due to the characteristics of the lithium-ion battery, it will not show negative electrochemical behaviour during the initial period of use. These faults can make it difficult to determine if a lithium-ion battery is dead. In this article, the author collected and summarized the safety performance standards of lithium-ion batteries that are commonly used at home and abroad. Through the research, it was found that there is no testing system and research base for the safety risks that may exist in lithium-ion batteries at home and abroad, and there is no fast and effective system for lithium-ion battery safety testing or research methods were established. .
With the increase of consumers for the electrical performance and safety of lithium-ion batteries, it is important for battery manufacturers, relevant departments and industry groups to study the method of determining the safety performance of lithium batteries. . -ion and establish a set of intuitive tools. , a quick and effective detection method improves the requirements under the current regulatory framework, improves the standards, clarify the basis for judgment, compensates for the shortcomings of the current lithium-ion battery regulations in the detection system, improve detection level of lithium -Ion battery storage. Performances, ensure the sustainable development of the lithium-ion battery industry, and protect the safety of consumers when using batteries.
