The power battery monomer is composed of six main components: positive electrode group, negative electrode group, porous diaphragm, shell, electrolyte and exhaust valve. The failure of any one of these components will damage the reliability of the power battery monomer, that is, reduce the reliability of the whole power battery monomer.
The power battery module is a series and parallel power supply of a number of cells through conductive connectors, fixed in the design position through the process and structure, and synergistically play the function of electric energy charging, discharging and storage. In order for these modules to be connected together, they are usually assembled by welding, screwing, and mechanical pressing.
However, today's focus is on the use of power battery monomer to form a power battery module, often used in two connection modes:
1. Combine the power battery cells in series first and then in parallel
The combination of power battery cells in series first and then in parallel can be used to improve the reliability of the power supply system. When the power battery cells in series first and then can not ensure the reliability requirements put forward by users, a group of power battery cells with the same specifications can be parallel to improve the reliability.
2. Combine the power battery monomer in parallel first and then in series
The combination of the power cell in parallel first and then in series can be used to improve the reliability of the power supply system. When the power cell in series first can not ensure the reliability requirements put forward by the user, the single power cell with the same specifications can be parallel in series to improve the reliability.
According to some calculation formulas, the reliability of the power battery module composed by first parallel connection and then series connection is higher than that by first series connection and then parallel connection. If considering the inhomogeneity of power battery monomer, the connection mode of parallel connection first and then series connection is beneficial to prevent the deflection of two power battery modules.
