Huawei's two important lithium battery research results flow out

On the evening of May 17, according to industry internal news, a batch of TSMC's already packaged chips was intercepted by the US Customs! TSMC did not disclose who the customers of this batch of chips are, and there is no way to know whether it has been released. There are rumors that this batch of chips belongs to Huawei! But there is no definite news to confirm. Huawei is the world's largest supplier of Chinese telecommunications equipment, and it has become the number one target of US siege on the issue of Sino-US tariffs. Suffered from US injustice and all spare tires were turned into normal, the US Department of Commerce stated that it had included Huawei and 70 related companies in its so-called 'entity list.' Without the approval of the US government, Huawei would not be able to purchase components from US companies. After the U.S. announced that Huawei’s 'double-sided clip killing' was announced against Huawei’s simultaneous purchase and sales control, in the early morning of May 17, He Tingbo, president of HiSilicon, stated in an email to employees that in order to honor the company’s commitment to customers With the promise of continuous service, the spare tire chips in Huawei's confidential cabinet are 'all positiveWhen talking about Huawei, the first thing that people think of may be mobile phones or communication equipment, but few people know that Huawei also has a lot of related research in the field of lithium-ion batteries. Huawei has invested heavily in research and development, not only in communications equipment, but also in research and development of lithium batteries. This time the spare tire chips are 'all positiveCombining experiment and simulation, the first achievement to solve the problem of lithium-ion internal short circuits: Safety issues caused by internal short circuits in lithium-ion batteries (safety issues caused by internal short circuits in lithium-ion batteries). The result is that researchers from Huawei Central Research Institute and Beihang University have proposed a highly reproducible new method for studying battery internal short circuits, and combined experiments and simulation methods to investigate the development process of internal short circuits. Internal short circuit has always been one of the important topics in the safety research of lithium-ion batteries. The current internal short circuit research methods developed include thermal triggering (paraffin wax, phase change materials, shape memory alloys, etc.), electrical triggering (charge/discharge, etc.) and mechanical triggering (acupuncture, built-in metal particles, perforated diaphragms, etc.). However, due to the closeness of the battery system and the influence of multiple factors such as heat, electricity and machinery, the process and mechanism of internal short circuit are far from reaching the level of deep understanding. The research on internal short circuit urgently needs new principles and new principles with high repeatability and high accuracy. method. Highlights of this method: 1. The method has high repeatability; 2. Combining experiment and simulation methods to explore the development process of internal short circuit. In this study, a small steel ball with a diameter of 2 mm was squeezed into the battery at a speed of 1 mm/min to trigger an internal short circuit. The voltage, temperature changes at different locations and real-time video were monitored during the experiment. The battery used in the experiment was a LiCoO2 cell phone battery provided by Huawei. Since the internal short-circuit process cannot be directly observed and measured, the author uses finite element and multi-physical parameter models to assist in the analysis of the internal short-circuit process. Among them, the force model is used to analyze the extrusion process before the internal short circuit, the battery model and the short circuit model are used to analyze the electrochemical behavior of the internal short circuit process, and the thermal runaway model is used to analyze the thermal runaway behavior. The above four models and thermal models are used in combination .