Battery Management System and Protection Circuit Modules


A Battery Management System (BMS) is an electronic system which allows you to monitor the charge and sometimes discharge of the cells that make up a battery. It is an essential component which guarantees optimum safety as well as good battery life. In order to optimise the battery’s capacity and prevent under-voltage and overvoltage, the BMS makes sure that the cells are balanced amongst themselves. There are two types of BMS, passive (dissipative) and active (non-dissipative).

BMS Enquiry


This cutting edge management system offers a plug-and-play functionality, making it really easy to use. With applications ranging from light commercial and electric vehicles to renewable energy storage systems, this active balancing system makes it possible to increase battery life by up to 30% offering multiple advantages throughout the battery value chain.

Active Battery Management Systems help:

Lower the costs of oversizing

Prolong battery life

Reduce weight and form factor

Increase reliability

Reduce charge time

Improve safety and security

The strong balancing currents, which are far superior to conventional systems (up to 25 times stronger),  allow for efficient balancing during the charge and discharge stages of the battery’s cycle. This results in optimum performance over time, fewer winter and storage problems, increased safety and usage statistics (conditions of use, charge cycle data, warning logs and more).


Dissipative systems use heat dispersion (resistors) to correct the difference in the state of charge of the cells and equalises their energy levels. This system is a lot less expensive than the active system as the latter uses more electronic components to balance the cells.

Simply put, with the passive system, when the cell is completely charged, the excess energy is dissipated using the Joule effect via a set of resistors. This allows the other cells to get to the same level and balance out. The limitation of this process is in that it is linked to a low balancing current, which, in the case of severe imbalance, will make it impossible to restore all of the cells to the same level.

During a technical review, it is necessary to ensure that the BMS is well ventilated in order to correctly release the excess heat. For active devices, the energy is redistributed between the cells. In comparison to the dissipative system, which can consume a lot of energy, all of the energy supplied is reused and this allows for much higher balancing currents.

Features Available:

  • SOH (State of Health)
  • SOC (State of Charge)
  • DOD (Depth of Discharge)
  • Total energy since first use
  • External communication protocols

Usual Protection Features:

  • Over-voltage cut off
  • Under-voltage cut off
  • Overload
  • Overheating


A PCM (Protection Circuit Module) is a circuit board which is made to protect the battery. PCMs are found in rechargeable Lithium battery packs. PCMs differ from BMS’ (Battery Management Systems) in terms of the features they offer. They offer protection systems but do not offer the additional features like balancing, SOC monitoring (state of charge), SOH (state of health), communication bus, etc.

Protection Circuit Module Features:

  • Over-voltage cut off
  • Under-voltage cut off
  • Overload
  • Overheating

Our BMS Products Showcase

16 cell BMS


  • Supports 4-series to 16-series cells
  • Battery chemistry support: Li-on, Li-polymer, LiFePO4 Battery packs
  • Voltage: 12.8V to 67.2V
  • Communication Protocols: CANBUS, SMBUS, HDQ,I2C,RS232,RS485

4 cell BMS


  • Supports 3-series to 4-series cells
  • Battery chemistry support: Li-on, Li-polymer, LiFePO4 Battery packs
  • Voltage: 9.6V to 16.8V
  • Communication Protocols: RS232/RS485/SMBus/Bluetooth

10 cell BMS


  • Supports 3-series to 10-series cells
  • Battery chemistry support: Li-on, Li-polymer, LiFePO4 Battery packs
  • Voltage: 9.6V to 42V
  • Communication Protocols: SMBus/I2C/HDQ/Bluetooth


    Advantages of using Enix Power Solutions for your applications:

    Bespoke solutions built to your specification

    Design & Characterisation