Last Updated on January 21, 2022
Well today, electric vehicles are becoming the high-priority of the automotive industry. While getting covered in the shine of these Electric Vehicles, we forget to take care of the most essential component of an electric vehicle, the Battery Pack. When it comes to cost, it covers approximately 40% of the vehicle cost.
The battery pack includes the Lithium-ion cells that strengthen the EV drivetrain and also, a smart solution known as the Battery Management System (BMS).
You can find BMS in almost all high-end electric devices that run on a battery, like a smartphone. What do you think, the battery percentage indicates the percentage of battery or its complete health?
Well, here BMS comes into play. It monitors all the cells of the battery and utilizes its complicated algorithm to evaluate the battery’s health, its percentage, and more. When we conclude the aspect of battery management to an electric vehicle, the complexity starts touching the heights.
Today, we are here to let you know about the battery management system (BMS) for electric vehicles, its need, and its key responsibilities. So let’s take a start.
What Is Battery Management System For Electric Vehicles?
An electronic system that manages the rechargeable battery to make sure that it operates efficiently and safely is known as Battery Management System (BMS). It is crafted to monitor the parameters linked with the battery pack along with its cells, apply the accumulated data to diminish safety risks, and optimize the performance of the battery.
The BMS is an electronic device that completely controls the diagnostic and safety functions for high voltage management and electric charge balancing.
Wireless BMS is also in trend today. It’s counted as an important factor in e-mobility. While the inclusion of wireless makes BMS very appealing, it demands a lot of care also. It incorporates all the required hardware and software parts for battery management, power, and more, on a single chip. The system allows maximum power use per cell for the best vehicle range, and also supports sustainable and safe zero cobalt battery chemistry.
Why Do We Need A Battery Management System (BMS)?
The low weight and high charge density of lithium-ion batteries have made them widely used by Electric Vehicle manufacturers. Yes, such batteries come as a complete pack, but they are highly unstable because of their size.
Moreover, one should take care while charging such batteries, as these should never be overcharged or also under discharge at any cost, which may demand to monitor their current and voltage. And you know what, this process may get a bit tough as many cells form a battery pack in an electric vehicle, and every cell needs individual observation for its efficient operation and safety and this demands a dedicated system known as BMS.
To get maximum efficiency for this battery pack, we should entirely charge and discharge such cells simultaneously at the same voltage which again needs the help of a BMS. Besides, BMS is also responsible for various other functions. Let’s discuss them below.
Key Responsibilities Of An Electric Vehicle Battery Management System
Well, BMS performs various functionalities. Let’s now discuss them.
When we charge and discharge, the battery cells should be monitored throughout the process. Every situation needs to be identified and also reported along with the activation of the safety mechanism. The battery includes various integrated circuits along with cell monitoring algorithms that conduct this function. Also, it includes a chain of command in which the cell-monitoring circuit, records the voltage and temperature of the cell and passes that data to a cell management controller.
At this phase, some algorithms run, which calculate the state of charge (SOC) along with the state of health (SOH).
Here, SOC is regulated to make sure that the battery is never undercharged or overcharged. It’s also identified as a fuel indicator of an EV as it points to the remaining power in the battery.
On the contrary, SOH is known for indicating the overall health of the battery and offers an insight into the operating situations of the battery. Depending on such a piece of information, battery maintenance and lifespan are scheduled.
Electric Vehicle Safety
When it comes to the battery management systems and EV power supply, safety becomes the primary concern. Well, an unknown thermal runaway can lead to a major mishap. As we have already discussed, the BMS accumulates data, such as temperature, current, and voltage to optimize the power.
The direct result of cell monitoring is battery power optimization. At one corner, when the functionality of cell monitoring determines SOC and SOH, on the other edge, the job of the EV Battery Management system is to keep SOH and SOC parameters within the defined values. While the battery undergoes charging, the EV BMS determines how much current should be permitted in the particular cell. While the EV operation is going on, when the electric vehicle is discharging, the battery management system makes sure that the voltage doesn’t go much low. It constantly communicates with the motor controller to make sure this doesn’t happen at all.
The BMS communicates with other Electronic Control Units (ECU) in the electric vehicle. It transfers the important data related to the battery parameters to the motor controller to make sure that the vehicle is running smoothly.
Battery Charging Optimization
Obviously, with time the battery cells fail. A smart EV BMS impacts this deterioration that leads to a change in the battery parameters, such as current, voltage, etc.
For instance – A battery cell heats up and gets damaged, and next starts getting charged but on lower voltage as compared to the rest. BMS here identifies this fault and then, optimizes the charging process so that all the cells start charging at the lower voltage. This reduces the load on the whole battery pack and increases its life.
EV BMS are emerging at a faster pace. A wireless battery management system is the latest rollout that frees up us from CAN, SPI, and BUS cables. As the battery packs enlarge, such wires lead to enhanced complexity, and next, it uplifts the hazards that are associated with various wires and then clogs the BMS.
Many such amazing technologies are getting launched today regarding the Electric Vehicle Battery Management System and its associated components. Such innovations will energize the progressive EV program that governments, OEMs, and other stakeholders are conducting with their whole strength.