Lithium battery packs and lithium battery packs, users who do not know much about lithium batteries may not know the difference, after all, are they all lithium batteries? In fact, the lithium battery pack contains a lithium battery pack. Let me introduce you to the specific situation!
Lithium battery pack
The lithium battery pack is composed of three parts: a battery cell, a protection board and a shell.
The battery cell is composed of a lithium battery pack, and the protection board is to protect the charging and discharging of the lithium battery pack in series; when fully charged, it can ensure that the voltage difference between the individual cells is less than the set value (generally ±20mV). The equal charge of each single cell of the battery pack effectively improves the charging effect in the series charging mode; at the same time, it detects the overvoltage, undervoltage, overcurrent, short circuit, and overtemperature status of each single cell in the battery pack, protects and extends Battery life; under-voltage protection prevents each single cell battery from being damaged by over-discharge during discharge.
There are two kinds of shell materials for lithium battery packs. There are differences between soft packs and hard packs such as aluminum and steel shells. However, soft-packed lithium batteries are more favored by manufacturers in the current market.
Lithium battery cell
There are parallel and series circuits in the lithium battery cells. Because the simple series circuit is due to the differences in the capacity, internal resistance, attenuation characteristics, self-discharge and other performance between the single lithium batteries, when the lithium battery pack is charged in series.
The single lithium-ion battery with the smallest capacity in the battery pack will be fully charged first. At this time, other lithium batteries are not fully charged. If you continue to charge in series, the fully charged single lithium battery may be charged.
The overcharging of lithium batteries will seriously damage the performance of the battery, and may even cause an explosion to cause casualties. Therefore, the lithium battery pack cells in the lithium battery pack adopt a combination of parallel and series to ensure the safety of the lithium battery pack and charge more power.
In addition to the circuit that combines parallel and series connection, the safety of lithium battery cells is guaranteed by the coordination of the battery management system and the charger. The battery management system is the device that has the most comprehensive understanding of the performance and status of the battery. Therefore, by establishing a connection between the battery management system and the charger, the charger can understand the battery information in real time, so as to more effectively solve the problem of battery charging.