Single-string battery BMS

What is a battery management system (BMS)?

The Battery Management System (BMS) is the hardware and software control unit of the battery pack. This is a critical component that measures cell voltages, temperatures, and battery pack current. It also detects isolation faults and controls the contactors and the thermal management system.

Why should you build a single-cell battery monitoring system (BMS)?

Better understanding and innovation in the field will help to increase safety, reliability and affordability of this crucial technology. Building a single-cell Battery Monitoring System (“BMS”) from scratch is a good way to learn about the cell-level performance and pin-point challenges under different battery use cases at this level.

Why is a single string battery set-up important?

A single weak or bad cell can exponentially lower the capacity of the entire battery pack. A properly engineered system can improve the overall reliability, but only when additional equipment and significant engineering time is invested. Whenever possible, a single string set-up should be considered.

How many BMS units can be used in a series?

In the above example, two BMS units, each capable of managing 8 cells in series must be used in conjunction with at least one contactor per string that automatically disconnects the string in the event of a failure, over-charge, over-discharge, or other fault.