Related matters that energy storage power supply manufacturers need to pay attention to when parsing lithium battery PACK

The production process of battery packs is called battery PACK. The battery pack can be a single battery secondary processing, or it can be a battery module with multiple batteries in series and parallel. A simple PACK is a process of combining batteries and accessories. This is general Most people with certain knowledge can operate. Professional PACK manufacturers must also have protection board development (software engineer/hardware engineer), rational design of battery structure (structural engineer), and reliable product simulation in different states and environments. Test laboratory (test laboratory), has a battery PACK production line with system certification, because most of the existing battery PACK technology is to link the cells together by welding, which also complicates the maintenance of battery problems. In addition, the battery Many thorny problems may be encountered when batch PACK. To ensure the reliability of batch products, excellent battery PACK technology and finished product testing are indispensable. The materials PACK contained in the battery PACK include battery packs, busbars, flexible connections, protective plates, outer packaging, output (including connectors), barley paper, plastic brackets and other auxiliary materials that together form the PACK. The characteristics of lithium battery PACK ① The raw material battery is required to have a high degree of consistency (capacity, internal resistance, voltage, discharge curve, life). ②Under normal circumstances, the life of PACK battery pack will be lower than that of single battery. ③Because of the different applicable products, it needs to be used under limited conditions. ④The lithium battery pack must be protected after it is formed, and the charge balance, temperature, voltage and overcurrent monitoring should be performed on it. ⑤The voltage and capacity requirements required by the design must be met. Method of PACK ①Tandem and parallel composition: Connect the batteries end to end, and the positive pole of battery A is connected to the negative pole of battery B. The negative pole of battery A and the positive pole of battery B are responsible for outputting the battery pack in series. At this time, the voltage is N of the single battery. Times (the value of N is equal to how many single cells are in series), for example: when the voltage of a single battery is 3.6V, when A battery and B battery are connected in series, at this time two batteries are used in series, and the voltage is equal to 3.6V x 2 u003d7.2V, if there are 10 batteries connected in series, the voltage is equal to 3.6V x 10 u003d 36V, and so on. When battery A and battery B are connected with the positive and positive poles, and the negative and negative poles are linked together, the form of simultaneous output from two batteries is called parallel connection. The battery voltage does not change in parallel, but the capacity increases. The algorithm is the same as the voltage calculation method, in order to achieve The designed voltage and capacity may require multiple batteries in series and parallel PACK battery packs. ②Battery cell requirements: select suitable cells according to the requirements of the battery pack design (according to the discharge and capacity requirements of the battery pack design), a batch of A-type batteries is the best choice, and the consistency of this type of battery is relatively high. , The error of capacity and internal resistance is usually about 1‰, and then through the secondary screening of the equipment, the cells with close values u200bu200bare prepared together, which can reduce the abnormal problem of the battery pack during PACK. ③ PACK process: laser welding, ultrasonic welding or pulse welding, which is a commonly used welding method, has the advantage of good reliability, but it is not easy to replace. The second is to contact through the elastic metal sheet. The advantage is that it does not need to be welded and the battery is easy to replace. The disadvantage is that it may lead to poor contact. In the process of assembling the flexible connection of the busbar, such as nickel sheet, copper-aluminum composite busbar, copper busbar, total positive and total negative busbar, aluminum busbar, copper flexible connection, aluminum flexible connection, and copper foil are used in the assembly PACK process. Soft connection. The processing quality of busbars and flexible connections needs to be evaluated from these aspects. ①Whether the material material meets the requirements of the composite material, the busbar material will increase the resistivity if the material does not meet the standard, especially it is necessary to confirm whether the relevant ROHS requirements are composited. ②Whether the processing of key dimensions is in place. The over-tolerance of key dimensions may cause insufficient safety distance between high-voltage devices during the assembly process and cause serious safety hazards. ③The bonding force of the hard zone of the soft connection and the stress absorption condition of the soft zone. ④Whether the actual processed soft connection and the overcurrent capacity of the busbar meet the design standards, and whether the insulated thermoplastic sleeve is damaged. The current industrial technology has reached a certain level. The lithium battery PACK process is not complicated. How to produce it quickly and ensure the quality of the finished product has always been explored by lithium battery PACK manufacturers. In the future, whether lithium batteries can satisfy people’s concerns about portable devices The requirements of the lithium battery are not only the technological progress of the lithium battery itself, but also the improvement of the battery PACK process. According to industry trends, lithium batteries will also develop towards larger cells or higher discharge platforms. Disclaimer: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous: Lithium battery PACK factory shares a detailed explanation of the module PACK process