"Geheimnis" der Great Wall Dayu Batterietechnologie - Lithium - Ionen-Batterieausrüstung
Cao Yongqiang, Technical Director of Dayu Battery of Great Wall Motors, said that Dayu battery technology is based on the concept of "Dayu water control, better to sparse water", "change blocking to dredging", and adopts the core technical principle of "control + conduction = communication" to build 4 layers The 5-dimensional safety matrix ensures that "large-capacity high-nickel cells", "any position of the battery pack", "heating two cells and continuously triggering thermal runaway" can achieve no fire and no explosion.(Lithium - Ion Battery Equipment)
From the perspective of the realization path, matching from the four layers of cells, modules, battery systems, and the whole vehicle, focusing on the five-dimensional design concepts of cell testing, system data, safety design, virtual simulation, and test verification, to achieve battery thermal runaway safety protection .
The technology has 8 innovative designs, including heat source isolation, two-way exchange, heat flow distribution, directional explosion-proof, high-temperature insulation, automatic fire extinguishing, positive pressure oxygen resistance, intelligent cooling, etc., covering heat source suppression, isolation, cooling, exhaust and other aspects In the field, ensure that the battery does not catch fire or explode.
For example, the heat source isolation is based on the protection of the two poles of the cell and the module, and the newly developed double-layer composite material is used between the cells, which solves the pain point of traditional aerogels that are not resistant to impact and the space requirement for cell expansion, while isolating the heat source.
High temperature thermal insulation composite material is used between modules, which can prevent flame impact and long-term heat transfer. The protective cover is designed with a directional explosion-proof outlet, which can quickly discharge the high-temperature gas and fire flow inside the module to prevent the heat spread inside the module.
Cao Yongqiang introduced that Dayu battery safety technology can effectively solve the problem of fire and explosion after the thermal runaway of cells in different chemical systems.
There are NCM811 ternary lithium batteries whose energy density can exceed 190Wh/kg, ternary lithium batteries with higher energy density as the nickel content increases in the future, and NCA (nickel-cobalt-aluminum) cells of the ternary lithium battery system and non-ferrous metals. Cobalt batteries, etc., as well as lithium iron phosphate batteries of different technical lines.
At the same time, Dayu battery technology can also be used with different PACK application technologies to meet the future CTC (Cell to Chassis) battery PACK and fusion methods, and further improve the overall rigidity.
In order to verify the safety of Dayu battery technology, Great Wall Motors conducted the most stringent thermal runaway test of NCM811 batteries at the same level, and strictly implemented the relevant standards and requirements of GB38031-2020 "Safety Requirements for Power Batteries for Electric Vehicles". Trigger multiple cells at any position in the cell and battery pack to simulate dangerous extreme scenarios in thermal runaway.
In addition, Dayu Battery has also built a package-level, thermal runaway combustion model to realize multi-dimensional fitting simulation of airflow and fire flow, and complete a fully digital thermal runaway virtual simulation under the condition of no real package. From the source, the safety drawbacks and hidden dangers in the development process are prevented, and the battery safety is fundamentally guaranteed.
It should be pointed out that more than 60 patents of Dayu battery technology will be open to the public for free, and will continue to improve battery safety. This technology will also be applied to the next-generation new electric vehicle platform to maximize user safety. The first model is the first model of the Sharon brand. a model.