What are the design requirements for electric vehicle power lithium battery packs

1. The ground clearance of the battery requires that the lower surface of the battery is protected by structural parts, and the following conditions must be met at the same time: in the state of maximum jump, the battery must have a certain clearance from the ground; ensure that it is competitive under full load. The ground clearance; the battery RESS must be protected in the forward direction; the battery RESS arrangement shall not be lower than the lowest surface of the surrounding body structure. 2. Restrictions on the Z-direction size of the battery in the human-machine layout of the passenger compartment. It can be seen from the human-machine layout of an electric vehicle project that there are 9 engineering indicators to be considered in the Z-direction latitude. The details are the distance H5 from the occupant H point to the ground Seat height H30, head space H61, distance from heel to ground H8, battery pack Z-direction thickness, battery pack ground clearance, car height H100, distance from the upper surface of the lithium battery pack to the upper surface of the floor, carpet and sound insulation The thickness of the cotton. Therefore, the height of the vehicle body is limited according to the styling requirements, and the Z-direction size limit surface of the battery pack can be derived according to the man-machine layout requirements. 3. The crumple space limits the size of the battery in the Y direction. Because the working voltage of the battery is generally higher than 300?V, and the electrolyte in the battery cell is highly corrosive, the lithium battery pack is arranged in the whole vehicle. It is necessary to set a reasonable and safe crumple gap, and the lateral collision conditions are particularly harsh. For detailed models, it is necessary to use CAE iterative decomposition methods to obtain a reasonable design for the lateral collapse distance between the battery and the sill plate. 4. The limitation of the whole vehicle load transfer path on the battery pack design The whole vehicle load transfer path can be roughly analyzed as: the front cabin load path, the front middle floor load transfer and the rear floor load path. Since the future layout of lithium battery packs will basically be tiled under the floor, the design of the floor load transmission path in the past is closely related to the structure of the battery pack. After topology optimization, the load transmission under the floor is mainly completed by arranging the longitudinal beam extension beam on the side of the battery and the No. 1.5 beam in front of the battery. The details are shown in Figure 8. The purple longitudinal beam in the figure passes through the triangular structure and No. 1.5 The beams are connected to the longitudinal beams of the front cabin for load transfer in frontal collisions; at the same time, the battery frame should also be used as a load transfer path to cooperate with the body load path; the beam structure inside the battery pack should be connected to the body 2/3/4 beams and the central channel The beam position remains consistent. 5. Endurance range Regarding the power demand for the same battery cell module, the endurance range is related to the energy density and capacity of the battery, and the battery capacity parameter is determined by the number and method of the series and parallel connection of its internal battery cells. , Will eventually lead to changes in the overall shape and size of the power lithium battery pack. Table 2 specifically lists the battery packs of different suppliers under the same cruising range target requirements, due to the difference in the energy density of the monomer and module and the series-parallel mode, the difference in power and battery pack size is caused. 6. The battery pack installation interface requires that the installation method of the power lithium battery pack on the entire vehicle directly affects its modal and strength. Generally, an installation point should be arranged at intervals around the battery pack. If the overall battery pack length is greater than 2mm, it is recommended Add a hanging point in the middle to improve the modal. The power lithium battery pack is the core energy source of new energy vehicles, which supplies driving power for the entire vehicle. It is mainly surrounded by a metal shell to form the main body of the battery pack. The modular structure design realizes the integration of the battery cells, and optimizes the thermal management performance of the battery pack through thermal management design and simulation. The electrical components and wiring harness realize the safety protection and connection path of the control system to the battery; the management of the battery cells is realized through BMS , And communication and information exchange with the vehicle. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous article: How to choose the capacity of lithium iron phosphate battery