Share |

Battery Management Systems (BMS)

The Battery Management System (BMS) is an essential component within a multiple cell battery pack. It monitors the state of a battery, measuring and controlling key operational parameters, and thus ensuring safety.

Our BMS incorporates our proprietary battery management electronics, and has four main objectives:

  1. protects the cells and the battery from damage
  2. prolongs the life of the battery
  3. maintains the battery in a state where it can meet the requirements of the application
  4. interfaces with the host application

Key features of  Battery Management System:

Cell balancing

The need for cell balancing comes from small cell-to-cell differences in self-discharge, capacity, and impedance leading to different charge states.  If all cells have the same capacity, then they are balanced when they have the same relative State of Charge (SOC).  In some instances the open circuit voltage is a reasonable measure of the SOC and battery pack cells are balanced when all the cells have the same voltage.  If one or more cells are not matched then the pack is not balanced and will have a low capacity, since the capacity of weakest cell in the string will determines the overall pack capacity. During charge of an unbalanced pack, one or more cells may reach the maximum charge level before the rest of the cells in the series.  On subsequent discharge these cells will become fully discharged before other cells in the string, significantly limiting the energy available. Cell balancing therefore improves the performance of the battery pack by extending battery life.

Safety protection

One of the prime functions of the BMS is to provide the necessary monitoring and control to protect the cells from out of tolerance ambient or operating conditions. This is of particular importance in automotive applications because of the harsh working environment. Our BMS is designed to be abuse-tolerant while delivering customers’ needs with respect to power, energy, operating temperature range, cycle life and calendar life.

Individual cell monitoring

Continual monitoring of all individual cells ensures that they are protected from damage by e.g. over or under-charging so that their lifespan is not reduced.

Charging/cycle life

By effectively controlling the operating conditions of the battery pack the cycle life is maximised. The BMS provides the optimum charging algorithm, maintaining all cells within their desired operating limits. This limits damage to lifespan and durability.

Communications

Our BMS provides information to the host application to ensure greater control and information for the user. This includes information on remaining capacity (fuel gauge), voltage, temperature, current draw, warnings and cycle count. For electric vehicles (EVs) and hybrid electric vehicles (HEVs) this is done via integration with the vehicle CAN Bus.

Modular BMS architecture

This ensures rapid prototyping, taking designs from concept to manufacture in a short space of time. It also means that the BMS can be easily configured to individual customer needs.

These features produce improved battery performance and lifespan, powering your application safely.

Enquiry Form

Please fill in this form below and we will endeavour to contact you within 48hrs.


©2016 Johnson Matthey Battery Systems