Process Standard for Lithium-ion Battery Pack Production

1. Assembly process

The assembly process of the cylindrical cell lithium battery pack is actually a litter similar to the engine assembly process of traditional fuel cars. The five systems are connected together by bolts, nuts, cable ties, clamps, wire harness throwing nails and other connectors to form an assembly.

2. Air tightness detection process

The air tightness test in the manufacturing process of the power soft pack lithium battery PACK is divided into two links: the thermal management system level air tightness test; the pack level air tightness test.

3. Software flashing process

Software flashing is also called software burning, or software filling. The software flashing process is to flash the BMS control strategy into the CMU and BMU of the BMS in the form of code. During the test and use of the lithium battery pack, the battery status information data collected will be processed and analyzed by the electronic control unit. Then, according to the analysis results, it issues control commands to the relevant functional modules in the system, and finally transmits information to the outside world.

4. Electrical performance testing process

Features of EV pouch cell pack:

① Lithium battery pack requires a high degree of consistency (capacity, internal resistance, voltage, discharge curve, life)

② The cycle life of the lithium battery pack is lower than that of a single battery.

③ Use under limited conditions (including charging, discharging current, charging method, temperature, etc.)

④ The voltage and capacity of the battery have been greatly improved after the lithium battery is formed, and it must be protected to perform charge balancing, temperature, voltage and over-current monitoring.