What are Cell,
BMS, Module, and Pack?
Cells are the battery cells produced by specialized manufacturers. They come in a cylindrical, rectangular, or pouch shape, among others. They are made from diverse materials, which differ by application, operating environment, and required properties. They are also called unit cells.
BMS(Battery management system)
BMS is a system that manages a battery through real-time monitoring of the lithium ion battery's input and output current, each cell's voltage and temperature, and other variables. It protects a battery pack from overcharge, over-discharge, overcurrent, and temperature/hardware abnormality. BMS is also capable of communicating data on the battery's state to external devices in addition to monitoring it.
Module (core pack)A module is a cluster of cells (batteries) that are wired and combined with each other. Protective parts and a protective circuit are added to a module as necessary.
PackA module in an outer casing is called a pack. Packs are categorized into soft packs or hard packs depending on the outer casing material.
Battery pack as a finished product
Internal structure of a battery pack
| No | Part names | Details / roles |
|---|---|---|
| 1 | Battery cell | Lithium ion cell |
| 2 | BMS circuit | Monitors the cell's state for safety control and protection |
| 3 | Wiring parts | Connect cells in series and parallel |
| 4 | External terminals | Output terminals to external equipment (for output of electric power and communication signals) |
| 5 | Outer case | Protects the inside of the cell as its housing |
| 6 | Insulating parts | Keep insulating the outside and inside of the cell |
*What is BMS?
BMS, the battery management system, manages a battery through real-time monitoring of the lithium ion battery's input and output current, each cell's voltage and temperature, and other variables. It protects a system from overcharge, over discharge, overcurrent, and temperature/hardware abnormalities (such as center tap, TH open/ short circuit, MPU runaway, and FET failure).
BMS is also capable of communicating data on the battery's state to external devices in addition to monitoring it.
