BMS is the Battery management system. As the name implies, it is a system for managing the power battery of electric vehicles, and the BMS plays the role of a steward of the whole vehicle battery system, with the main functions of sampling and measurement and evaluation management, which are composed of BatteryControl Unit (BCU) and BatteryManagementUnit (BMU).

As one of the three electric systems of the car, the battery accounts for about 30-40% of the cost of the whole car, so the BMS is also an extremely important part of the whole car. However, BMS is not a product of the electric vehicle era, it has changed with the development of battery technology and the complexity of application scenarios.

From copper and zinc batteries to lead-acid batteries and now lithium or sodium ion batteries, battery technology has made great progress in recent decades. Early batteries, such as nickel-cadmium batteries, often came in the form of a single cell, so the state of the battery did not need to be closely watched.

But to the later, the battery in the form of multiple series connection, the problem comes: the characteristics of each battery there are differences, the battery between the power balance there are differences.

"Two people three feet" we have played it, it is a test of teamwork ability, there is always a pig teammates step big, three days and two noses, time, the body collapsed, the hearts of the people scattered, can still run?

Changed to the same battery, the end result will lead to a battery is often in a state of overcharge or over discharge, the overall battery pack life greatly reduced, so people will manually check the consistency of the battery on a regular basis.

The traditional sense of manual work is time-consuming and labor-intensive and can not do real-time monitoring, so the modern sense of the BMS was born. Modern BMS function is also from frugal to extravagant, from the early simple voltage, temperature, current and other basic parameters monitoring, slowly developed to a number of functions such as real-time monitoring, battery balance management, overcharge and overdischarge prevention, etc..