Battery Management System For Electric Vehicle

Electric vehicles are quickly becoming an essential and required element of the global automotive ecosystem. It is critical to comprehend some of the primary components of an Electric Vehicle that aid in the efficient operation and operation of the vehicle. One such component is the battery pack, which accounts for over 40% of the total cost of an electric car.

 The Battery management system guarantees the protection of the Battery Pack and manages the battery. Almost every high-end electronic equipment that operates on batteries has a Battery Management System. From your smartphone to e-bikes and e-cars, there’s something for everyone.

The Battery Management System is responsible for monitoring each cell of the battery and employs a complicated algorithm to accurately assess battery % and health. When we apply the battery management component to an electric car, the complexity increases significantly. In this article, we will look at everything about the battery management system for electric vehicles

Battery Management System What Does It Really Do in Electric vehicles? 

A battery management system is a system that controls the full operation of an electric vehicle using its battery pack to ensure that it functions safely and effectively.

It checks the proper functioning of all of the cells in the battery pack in every manner possible to rule out any flaws in the cells and analyses the battery’s health; it will also notify you if the battery’s health deteriorates, and it will display the battery’s health even when it is charging, among other things.

Due to enhanced performance, such as a strong acceleration rate and extended driving distance from a single charge, battery technology (Electric vehicles ( EV) are becoming more fashionable and have achieved better customer acceptability in recent years.

A recent study also reveals that integrating EVs with the electrical grid has some interesting benefits. One of these is the utilization of electric vehicle batteries as a kind of distributed energy storage.

As a result, excess electricity generated by renewable energy sources can be preserved in electric vehicles and released to the grid as needed.

However, unlike typical Nickel-cadmium and lead-acid batteries, Li-ion batteries can only be used in a limited range of temperatures and must be properly monitored, maintained, and safeguarded.

When used in big applications, such as electric vehicles and centralized energy storage, in which a large number of Li-Ion cells are coupled to just provide adequate voltage and current, this problem becomes more serious.

The essential component of the solution is a reliable and efficient battery management system (BMS). This article begins with a quick overview of BMS characteristics, followed by a step-by-step approach on choosing a commercial BMS from the emerging markets a customized BMS for more user control.

The usefulness of a BMS in managing and safeguarding Li-Ion cells mostly during charge and discharge cycles is demonstrated using an Elithion Lithimate Pro BMS.

Is Battery Management System Really Required For Electric Cars?

Lithium-ion batteries are commonly used as a power source in current electric cars. In electric cars, nominal pack voltages will range from 300 to 800 volts.

Because batteries make up such a large part of an electric car, keeping the voltages low and in order to ensure the safety of the electric vehicles, batteries are critical.

The Battery Management System (BMS) is necessary to keep EV Batteries safe from overheating. BMS is essential not only for the safe operation of electric vehicles but also for their efficient operation.

Major Functions Of Battery Management System.

There are some major functions that are done by the battery management system, we will look into the main functions one by one

1) Improved Security And Energy Efficiency

Because Lithium-ion batteries run at greater voltages, it’s critical to keep the battery cells and the electric car safe. The safety of the battery is ensured by the battery management system. During both charging and discharging, it continually checks more or less every cell of the battery.

Also, every cell in a battery pack experiences a varying temperature depending on its level of charge, altering the pack’s overall performance. The sensors are used to detect the current, voltage, temperature, and other properties of each cell directly, and the BMS monitors all of this to ensure that the batteries run safely.

The Battery Management System also monitors both the charge and health of the battery. 

2) Charge Of Battery

The charge level of a battery refers to how fully charged it is in relation to its capacity to endure for a given amount of time.

The units of charge are measured using percentage points, with 0 representing an empty charge and 100 representing a completely charged battery. The charge level of the battery is set in such a way that it is never charged over or below the limit.

The charge level may be used to calculate how far an Electric Vehicle can travel before the battery has to be recharged or drains completely.

3) Health Of Battery

The health level of a battery refers to its state in comparison to its optimum condition at the time of production. The ability of a battery to maintain a charge proportional to the total capacity of the battery for a certain stretch of time before reducing is determined by its health units.

The lifespan of a battery is used to determine whether or not the battery requires maintenance.

BMS also guarantees that the battery is operating at the proper voltage and current flow, as well as maintaining the temperature parameters at which the device may be expected to run without sustaining any self-damage.

4) Cell Balancing

Cell balancing is an important activity for extending the life of a battery by decreasing the number of charge and discharge cycles. The BMS helps the battery recharge and discharge evenly, allowing it to last longer.

The charging and discharging rates of every cell in a battery pack are balanced by the Battery Management System. BMS also used either active or passive balancing to ensure that all of the cells were taken care of for an extended length of time.

5) Passive Balancing

The cells are discharged via a bypass channel that is largely dissipative in character in the passive cell balancing procedure. The surplus energy from the cells is evacuated by providing a single drainage point for all of the cells.

Instead of charging each cell at a distinct time, this allows for a complete recharge of all cells at the same time. The capacity of a module is still restricted by the weakest cell, which necessitates the use of an extra cooling mechanism to prevent overheating.

This approach is far more straightforward and straightforward to install than active balancing systems, since the bypass may be external or incorporated, making the system more cost-effective.

6) Active Balancing

The charge is transferred between the cells via exploratory charge commuting or capacitance charge commuting in the active balancing approach. Rather than dissipating and wasting energy, it redistributes it across cells and this necessitates the addition of additional components to the system, which results in an increase in cost for charging the battery cells.

7) Communication

Different Electronic Control Units connect and communicate with the BMS. It transfers the information to the control circuit to guarantee that the electric cars function smoothly with no interruptions in the power source.

In the case of Alternate Current recharging, the Battery Management System connects with the integrated charger to regulate the charging of the battery pack by maintaining the proper flow of current from the charger with no fluctuations in charging speed. 

Primary Purpose of the Battery Management System

The fundamental function of a battery management system (BMS) is to safeguard the battery from harm under a variety of operating situations.

  • The use of rechargeable batteries outside of its safe operating region is prohibited.
  • Internal switches disconnect the battery if it strays beyond its safe working range.
  • Requesting that gadgets lower their battery’s power demand
  • Using heaters, cooling systems, and blowers to actively manage the environment

Other Functions of BMS are

  • Management of energy efficiency of the battery
  • Cell balancing
  • Controlling its 

There are certain functions that A battery management system does have let us look at those functions which are barred by BMS.

  • Increased current flow protection
  • Over voltage protection
  • Low voltage protection
  • High heat temperature protection
  • Low heat temperature protection
  • Over pressure protection
  • Battery current leakage detection. 

The main reason that a battery management system cannot do these activities is that it will just manage the battery and not solve the problems; it will only notify you if a problem arises. A BMS is a device that links the load to the battery in order to safeguard the battery from excessive load variations.


1) What is a battery? 

The term “battery” refers to a device that transforms chemical energy into electrical energy.

2) What are the benefits of monitoring a lithium-ion battery with BMS? 

high-density power
High responsiveness, extended life. 
minimal self-discharge.
low maintenance costs, and low environmental effect

3) Why do electric vehicles need an advanced battery management system? 

The smart battery management system may greatly boost the electric vehicle’s performance. The battery management system is an important part of electric cars since it ensures battery safety, efficiency, and reliability.


To secure and control high voltage batteries in electric and hybrid electric vehicles, a battery management system is required. Lithium-ion batteries are commonly used in electric vehicles, can readily be damaged if they are not properly maintained.

It can also aid in the management of uncontrolled charging, discharging, high or low temperatures, and so protect the battery cells from harm. A battery management system aids in the protection of the battery from such harm.

A battery management system, in basic terms, prevents your electric vehicle battery from losing capacity over time.

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