How does Huawei solve battery thermal runaway under fast charging?

Although Huawei insists that it does not build cars, its research and development of power lithium batteries has not fallen behind. During the fast charging process of power lithium batteries, especially high energy density power lithium batteries, a lot of heat will appear in the active materials inside the battery cells. If this heat cannot be conducted to the outside of the battery in time, it will cause the battery The temperature rises rapidly and there is a risk of thermal runaway. In order to solve the thermal runaway problem involved in fast charging, on April 20, Huawei published a patent for 'a battery cell, a power lithium battery, a power lithium battery pack, an electric device and a manufacturing methodCurrent methods of enhancing heat dissipation, such as arranging a liquid cooling or direct cooling system outside the battery case, conduct the heat of the battery case to the outside, but the heat transfer path from the battery cell inside the battery to the battery case has a large thermal resistance. As a result, the heat generated by the cells inside the power lithium battery cannot be quickly transferred to the outside of the battery. Huawei’s solution is to set the 'distance between the first current collector and the bottom of the battery case' in the battery cell to be smaller than the 'distance between the diaphragm and the bottom of the battery case' so that part of the heat generated by the battery can pass through the current collector. Conducted to the battery case. (A side view of a laminated battery cell) Since the thermal conductivity of the current collector is much greater than that of the diaphragm, part of the heat generated in the battery cell inside the power lithium battery can be quickly transferred to the battery shell through the current collector, making the power lithium battery The heat generated by the internal battery cell is quickly transferred to the outside of the battery. (Comparison table of the heat transfer coefficient of each material of the diaphragm and the current collector) On this basis, the first polar piece (the positive pole piece) is in contact with the bottom of the battery case, and the transmission from the inside of the battery cell to the battery case is further added. The thermal conductivity of the thermal path, the heat generated by the cells inside the power lithium battery can be transferred to the outside of the battery more quickly. This is not the first time Huawei has stepped into battery thermal runaway. Previously, it also disclosed a patent for 'a control method, device and battery pack for alleviating the spread of thermal runaway in battery packsEffectively alleviate or prevent the spread of heat out of control. In terms of battery applications, Huawei has launched a three-power cloud service that combines its core technologies in the battery and ICT fields to solve the battery safety and life management issues of new energy vehicles. In terms of the layout of electric vehicles, the BAIC Alpha S series recently launched adopts Huawei's fast charging technology, charging for 10 minutes, which can add 197 kilometers of battery life. In addition, Zhu Huarong, chairman of Changan Automobile, said that the specific names of the high-end brands jointly built by Changan Automobile, Huawei and CATL will be announced in the near future, and the first two smart electric vehicles will also be launched by the end of the year.