How to assemble battery module and battery pack?

Once the single cell aging process is complete, the assembly proceeds to the module combination stage, with an initial screening to test individual cell capacity, dynamic internal resistance, and voltage data. The goal is to select cells with similar parameters for matching.Battery recycling machine A large battery pack typically consists of multiple battery modules, each comprised of numerous single cells connected through series and parallel combinations. Series connections enhance the voltage of the battery module, while parallel connections increase its capacity. The matching principle for single cells within the battery module generally prioritizes capacity during series connections to avoid overcharging or overdischarging issues during the charging and discharging process. In parallel connections, internal resistance takes precedence to prevent uneven current distribution and related overcharging or overdischarging of cells with lower internal resistance.

Following single cell matching, the assembly process involves securing the single cells to the module structure of the battery pack. Busbars are used to connect the electrode poles of the single cells together.cylindrical battery pack mahcine Despite the careful matching of single cells in the battery pack and the excellent consistency of capacity and internal resistance, cycling may lead to voltage deviation among the single cells. To address this issue, an equalizer is often added to the battery pack. When voltage deviation reaches a certain level in some single cells within the battery pack, the equalizer intervenes to restore voltage uniformity among the single cells. Equalizers can be categorized into dissipative equalization and non-dissipative equalization, with dissipative equalization involving discharging higher-voltage cells to dissipate electrical energy as heat into the environment. Non-dissipative equalization is more complex, transferring power from higher-voltage cells to lower-voltage cells to balance voltage levels among the single cells.

Effective temperature management for the battery pack is essential. Temperature significantly impacts lithium-ion battery performance, especially in configurations with numerous cells where charging and discharging generate heat. This can result in uneven temperature distribution within the battery pack,cell stacking machine affecting electrical performance and reliability. Research indicates that reducing the maximum temperature difference within the battery pack can substantially enhance reliability. Therefore, good internal heating and cooling systems are essential. Heating is typically achieved using heating bands, and there are recent innovations to rapidly raise battery temperatures. Cooling mainly involves air-cooling, including both forced and non-forced methods, as well as water-cooling for superior heat dissipation.

Power battery packs typically consist of multiple battery modules connected in series to supply power for various applications as per user requirements.

To enhance safety and performance, a Battery Management System (BMS) is installed in the battery pack. BMS controls battery pack charging and discharging, preventing overcharging and overdischarging. It also manages the equalization system and thermal management system to improve battery pack performance and lifespan. To further enhance safety, thermal runaway warning and blocking devices are added to mitigate the potential harm from thermal runaway events within the battery pack.