SAE standards on lithium-ion power batteries
The Society of Automotive Engineers (SAE) is the largest automotive engineering academic organization in the world. The standards established by it are highly authoritative, and are widely adopted by the automotive industry and other industries, and a considerable part of them have been adopted as American national standards. In February 2011, SAE promulgated the new standard SAEJ2929-2011Electri and Hybrid Vehicle Propulsion Battery System Safety Standard-Lithium-based Rechargeable Cells (safety of lithium-ion battery system: lithium charging) Battery). This standard is proposed on the basis of summarizing the various safety testing standards for power storage batteries promulgated by SAE and other relevant international standards. Many mature international standards are cited in the standard, and detailed requirements are made for the safety performance in the event of a single functional failure of the charge/discharge control system and the temperature control system.
During the test, SAEJ2929-2011 separately regulated the discharge current of lithium-ion batteries for pure electric vehicles and hybrid electric vehicles, and described the battery system status during the test in detail. This standard can be divided into two parts. One part is to test the general conditions that may occur during the operation of electric vehicles, such as vibration, thermal shock, vibration resistance, etc.; the other part is to test the abnormal conditions that may occur during the operation of electric vehicles. Tests, such as drop, water immersion, mechanical shock, simulated vehicle fire, short circuit, overcharge protection, overdischarge protection, etc. The battery safety performance test in the case of water immersion, automobile fire, temperature shock and collision in this standard better guarantees the safety of the battery. In addition, SAE2929-2011 also stipulates that the samples must meet the test requirements during the test and during the one-hour observation period after the test to be considered as passing the test.
UL standards for power batteries
Underwriters Laboratories (UL) is the most authoritative safety testing organization in the United States and a large private organization engaged in safety testing and appraisal in the world. In 2011, UL promulgated the new standard UL2580 Standards for Batteries of Use in EV (Battery Standards for Electric Vehicles) on the safety of power batteries. UL2580 mainly includes the following three aspects:
Electrical performance test: It mainly includes overcharge, overdischarge, short circuit, etc. In addition, this standard also strengthens the compatibility test of battery pack and charging system, and the electrical unbalance test of single cell or battery module/battery pack in the battery pack. , As well as safety assessment of reinforced insulated circuits and electrical misuse tests related to electric vehicle applications.
Mechanical safety test: It mainly includes general mechanical tests such as vibration, drop, impact, and squeezing. At the same time, it also adds battery flip test and quick acupuncture test.
Environmental testing: It mainly includes cold and heat shock salt spray, water immersion, external fire, internal fire, etc. A more stringent method is adopted to simulate the abnormal conditions that the battery may suffer in the use environment.
In addition, UL2580 has also specifically increased the safety test standards on the production line to meet the basic safety design requirements of various parts or components in the battery pack. The content covers the flame-proof grade of non-metallic materials, UV aging resistance, and the corrosion resistance of metal materials. The requirements for flame resistance and electrical insulation of battery shells, etc. At the same time, safety is strengthened in the special battery management system (Battery Management System, BMS), cooling system and protection circuit design of large-scale battery packs of electric vehicles.