The battery pack usually refers to the packaging, packaging and assembly, and the operation process of the assembled battery. Since the lithium battery forms a certain voltage and capacity according to the series-parallel circuit of the single lithium battery, the lithium battery protection board is installed to charge the battery. Discharge assembly operation process.
For example: two batteries are connected in series to form a specific shape according to customer requirements, we call it a pack.
The pack battery assembly process is a crucial step in the production of lithium battery packs, and its importance is also looking to become more and more significant with the continuous development of the electric vehicle industry market. At this stage, automotive power batteries are basically composed of the following systems: battery modules, battery management systems, thermal management systems, electrical and mechanical systems.
Six major factors to be fully considered in the product structure design of lithium battery pack:
1. Lithium battery pack structure pack design involves many levels:
For example, in the design of mechanical structure, strength, seismic grade, heat dissipation/heating, moisture-proof, dust-proof, etc. should be fully considered; electrical design should be fully considered, safety regulations, EMC safety regulations, etc. should be fully considered; lithium battery management system design should also be fully considered. It is necessary to fully consider overcharge, power loss, over temperature, detection accuracy, battery balance, etc., to ensure that the battery is safe and reliable, it must be properly designed and confirmed by the industry market.
2. Factors should be fully considered in the product structure design of the power lithium battery pack
a. Maintain the balance of air pressure inside and outside the lithium battery pack. Since the temperature of the lithium battery pack will change during the charging and discharging operation, the air pressure inside the battery pack will change. The PUW explosion-proof valve is breathable and not easy to seep water, so it can keep the battery pack. The air pressure inside is always the same as outside;
b. Explosion-proof, once the lithium battery pack is thermally out of control, the air pressure in the battery pack will increase significantly, and the battery pack will be in danger of explosion at this time. Therefore, the PUW explosion-proof valve becomes a breakthrough, which can quickly release pressure in a timely manner.
c. Moisture-proof, waterproof grade reaches IP68;
3. Pay attention to how the battery is connected
In the combination of pack lithium battery pack, in addition to the control of the safety and reliability protection level of the battery pack, cooling and heating, especially the method of battery connection, the accuracy of BMS measurement should be fully considered. It is common to ignore the impact of voltage drop on the test, which in turn results in the equalization ability of the battery pack.
4. Pay attention to moisture-proof and shock-proof grades
Moisture-proof and shock-proof grades are very important in the structure of lithium battery packs. Speaking of the battery pack, it is a commercial complex, which involves many aspects, but if the details can be done well, it is already very good.
5. Integration of product design
Integration of lithium battery pack product structure design: After a single module pack is completed, it must be connected in series to form a battery pack. At this time, the series connection between each other should be fully considered to meet the need for a fast and safe series interface form.
6. Internal insulation design problems
Internal insulation design problem of battery pack product structure design: The battery has already fully considered the insulation problem of positive and negative electrodes in the design of the battery, but the uncertain factors of the vehicle battery are too complicated, so it must be set separately in the operation process of the pack battery design. The battery can still be safe and effective under various complicated environments such as shock, vibration, and humidity, under certain insulation conditions.