The lithium battery is mainly composed of two large blocks, the battery cell and the protection board PCM (power battery is generally called the battery management system BMS), the protection board is mainly composed of the protection chip (or management chip), MOS tube, resistor, capacitor and PCB board; The battery cell is equivalent to the heart of the lithium battery, the management system is equivalent to the brain of the lithium battery, and the battery cell is mainly composed of positive electrode material, negative electrode material, electrolyte, diaphragm and shell.
There is a certain difference between the two, and the natural size is not the same.