Flexible cell management system

Abstract

The invention discloses a flexible cell management system and belongs to the cell management and energy storage field. The flexible cell management system can realize flexible measurement, protection and management on cells of the cell groups, has low requirements for external voltages and can be directly connected with AC. The flexible cell management system comprises multiple cell management units connected in serial and in parallel, wherein each cell management unit comprises one or two cells and four or six switches, and can realize external port positive connection, reverse connection and bypass functions, and the switches can any type of diodes, triodes, relays, thyristors, silicon controlled rectifiers, MOS tubes and IGBTs and can also be combination of all the types above to form a bi-directional switch module or device. The flexible cell management system can be composed of multiple cell management units in series, in parallel, in series and then in parallel, in parallel and then in series, or in hybrid connection mode. The flexible cell management system has low requirements for external charging and discharging voltages and can even realize external AC charging and discharging, the flexible cell management system further improves reliability of the cell groups, and internal resistance can be easily and accurately measured.

Description

technical field [0001] The invention is a battery management system, which realizes the balance, protection and management of each battery in the battery energy storage system, and realizes a flexible external voltage interface. Background technique [0002] With the development of new energy and technology, battery technology has developed rapidly, and many new types of batteries have emerged. However, the voltage and capacity of most batteries are relatively low. To be used in large-capacity applications, such as new energy vehicles and new energy distributed energy storage, multiple batteries must be connected in series and parallel. However, since the characteristics of each battery are not exactly the same, it is necessary to add a management or protection circuit for effective monitoring, balancing and protection when the batteries are connected in series and parallel. Many battery management systems have appeared up to now, but all of them have problems such as weak ...

AI Technical Summary

Problems solved by technology

However, since the characteristics of each battery are not exactly the same, it is necessary to add a management or protection circuit when the batteries are connected in series and parallel for effective monitoring, balancing and protection.

Many battery management systems have appeared up to now, but all of them have problems such as weak control ability and difficult parallel connection between battery packs. In addition, the external port voltage requirements of battery packs are generally high, and the external voltage must be a suitable direct current, otherwise it will damage to the battery pack

However, in many applications, the external voltage fluctuates, even alternating current. In this case, an external converter is needed between the battery pack and the external circuit, which increases the system cost and reduces the reliability.

Images