18650 is currently the most mature power battery product, and without safety, there can be no maturity... Maturity also means safety, efficiency, low cost, high consistency, and high reliability. "At the 13th China International Battery Technology Exchange Conference/Exhibition (CIBF2018) held in Shenzhen recently, Dr. Luo Zhaojun, Chief Engineer of Shenzhen Bike Power Battery Co., Ltd., praised 18650 batteries beyond words. This is not only due to the consistent focus of BAK Battery on 18650 batteries, but also because BAK Battery has discovered many excellent characteristics of 18650 batteries during the almost extreme research and development process, and gradually demonstrated these characteristics in various types of 18650 batteries, creating its own world with 18650 batteries.
During the CIBF2018 exhibition, Battery China Network conducted an exclusive interview with Dr. Luo Zhaojun and had in-depth discussions on the safety issues of 18650 batteries.
The safety issue of power batteries is a word that runs through our conversation with Dr. Luo Zhaojun. In her words, "For lithium batteries, safety is 1. Adding many zeros after it is valuable, but if safety is not solved, it is meaningless to pursue other performance improvements." And for the safety of BAK batteries, it is also Dr. Luo Zhaojun's proudest aspect. As of the end of 2017, a total of 110000 new energy vehicles had been equipped with BAK batteries, and so far there has been no safety accident caused by battery cells.
In the upcoming implementation of the "Safety Requirements for Lithium ion Power Batteries for Electric Vehicles", it is stipulated that the needle puncture detection in the strong inspection of power batteries will be cancelled. In response, Dr. Luo Zhaojun stated that needle puncture rarely occurs in actual use, but the thermal runaway of battery modules has always been a key concern for the safety of power batteries in various fields. Despite the cancellation of needle puncture testing, battery companies need to put more effort into preventing battery thermal runaway caused by various factors to ensure battery safety.
Regarding the safety performance of the recently launched BAK 18650-3.0AH high-energy cell products and battery modules, Luo Zhaojun is proud to say, "BAK Battery has been developing the 18650-3.0AH battery cell since 2015. After three years of chemical design freezing and process design freezing, it successfully solved the directional blasting technology of high-capacity single cells and implemented the 'Fail Safe' concept of single cell failure in the entire package and intact package
The almost stringent requirements actually stem from the "pressure" of car manufacturers in terms of safety. The current national standard requirement of no explosion or fire within 5 minutes is actually aimed at square batteries, but cylindrical batteries cannot have this problem no matter how long it takes. "Luo Zhaojun admitted," The requirement of the whole vehicle factory for us is that you can never explode or fire. "That's why BAK batteries are" heart wrenching "for battery safety. The high nickel material used in the latest 3.0AH 18650 battery cell is crucial for controlling the heat release of the cell. Luo Zhaojun also stated that the selection of positive electrode materials can basically solve more than 60% of thermal runaway problems. In addition, by doing sufficient research on hardware structure and overall module protection, it is possible to achieve 100% avoidance of thermal runaway.
The 2.9AH high nickel+silicon alloy 18650 battery, which was produced in 2015, became the first battery cell product in China to pass the full package thermal runaway detection; The 3.0AH 18650 battery cell passed the thermal runaway test on the entire vehicle; The 3.2AH battery cell is scheduled to be offline in 2018, and there are expected to be orders in 2019; The 4.5AH product has been developed and is ready for mass production at any time; 4.8AH battery cells are undergoing small-scale trial production and have already undergone small-scale loading tests
It is based on years of deep cultivation of 18650 batteries that BAK batteries continue to develop and layout products along the path of cylindrical batteries. Square batteries and soft pack batteries will also become important product lines for BAK batteries' future development.
After ten years of deep cultivation, BAK Battery has achieved remarkable results in cylindrical battery cells. And continue to provide supporting services for well-known domestic and foreign vehicle manufacturers such as BMW, SAIC General Motors, FAW, Wuling, Yundu, Jianghuai, Zotye, and Leapmotor. In addition to hoping to mass produce 3.2AH and 4.8AH battery cells, Luo Zhaojun still hopes to completely solve the safety issues of power battery packs at the system level, "guarding the healthy development of the new energy industry with safety and low cost
