Whether you use lithium-ion batteries as a backup power source or in an RV, they maintain vital systems functioning. Furthermore, you do not want a safety hazard when these batteries are in use. It is crucial to invest in a battery management system (BMS) for this reason.
Depending on usage and storage circumstances, lithium-ion batteries can have a long lifespan. They can endure longer, though, if a BMS is there to protect them. In order to lower the risk of thermal stress, overcharging, or overdischarging, the battery management system makes sure the batteries are operating at the ideal temperature and charge.
Let’s investigate the precise nature of a BMS and how it functions. We’ll dive into the fundamentals in this guide to help you make smart financial decisions.
Deep-cycle batteries and battery management systems work better together
Let’s first go over what deep-cycle batteries are and why you need them before getting into the specifics of management. These batteries maintain their performance and longevity even after enduring heavy depletion and recharge cycles. If you require consistent, dependable electricity for extended periods of time, they’re a great option. For off-grid setups, boats, RVs, and renewable energy systems, deep-cycle batteries are perfect.
Comparing lithium-ion batteries to their lead-acid cousins, the former usually have a longer cycle life. They are more resilient to several charge-discharge cycles and offer consistent power during critical situations, such as long-distance driving or seafaring excursions.
However, lithium-ion batteries can be costly, so you’ll need a system that safeguards your investment in addition to keeping your batteries secure. Your batteries will run securely, effectively, and dependably thanks to a BMS.
In particular, it keeps an eye on your battery’s vital indicators—voltage, current, temperature, and state of charge—and takes preventative action to avoid serious problems. These could be anything from a potentially harmful thermal runaway to overcharging. A BMS is essentially your first line of protection against accidents involving batteries.
Parts of a BMS
The particular parts differ based on the use and design of the system. Nonetheless, the majority of battery management systems have a few essential components:
- sensors and electronics that track each battery cell’s voltage, current, temperature, and charge level continually.
- a control logic to process information and carry out instructions to manage the balancing, charging, and discharging processes.
A Battery Management System's Features
As previously stated, the main purpose of the BMS is to safeguard battery cells against harm resulting from excessive charging or draining. However, an excellent BMS can do more. For example, it can determine how much charge is left in the battery and keep an eye on its temperature, health, and safety by looking for internal shorts and loose connections.
When making an investment in a battery management system, look for these features:
Monitoring of Voltage
Among a BMS’s most crucial duties is this one. The lifespan of a battery can be considerably shortened by voltage changes.
Every single cell in the battery pack is connected to the BMS circuit. To make sure it stays within safe operating bounds, it takes a sample of each cell’s voltage and compares it to predetermined criteria. In order to shield the battery pack from harm, the BMS initiates preventative steps when a cell voltage rises or falls below predetermined thresholds.
To restore the voltage to normal, the battery management system can also alter the power flow to or from the battery pack. As a final option, it also turns off the battery to safeguard users and the cells.
Control of Temperature
Another important factor that significantly affects battery life is temperature. Thermal runaway can occur when temperatures are high. Cell failure is the result of a chain reaction where rising temperatures cause it. There is a serious risk to battery safety.
Temperature sensors are positioned in strategic locations throughout the battery pack to track each cell’s temperature. Real-time temperature fluctuations are continuously measured by these sensors, and the results are compared to predetermined thresholds. To safeguard the battery and the system, the BMS will completely shut down the battery if the temperature rises above these thresholds.
Estimated State of Charge
The quantity of electrical energy that a battery can hold at any one time is known as its state of charge, or SOC. SOC, to put it simply, shows the battery’s remaining charge in relation to its total capacity.
Although you can use the battery voltage as a stand-in, there is no direct way to measure the status of charge. Using a shunt-based battery monitoring system is the most reliable approach to keep an eye on what is entering and leaving your batteries and to calculate their state of charge.
Protection against Overcharge and Over-Discharge
Overcharging occurs when a battery is charged above the recommended voltage limitations. This can destroy the chemistry and cause overheating and gas production. A battery management system keeps an eye on each cell’s voltage. Until the user modifies the charging voltage, the battery will be turned off if the cell voltage rises.
When a battery is subjected to a high electric load, over-discharge may occur. Even when not in use, batteries naturally gradually drain over time. Age and extreme temperatures can also cause a fast discharge that damages cells and reduces their capacity. By use of cell balance, the BMS guarantees uniform charging and discharging.
Balance of Cells
To keep batteries alive, cell balance is an essential function. A voltage imbalance can be brought on by a number of things, including differences in cell chemistry or uneven aging. These disparities may result in uneven charging, which reduces battery longevity and deteriorates performance.
To maximize performance, the battery management system makes sure that each cell receives the same amount of charge. Passively, it balances the cells. In order to discharge overcharged cells until they match other cells, passive balancing uses simple resistance.
Fault Detection and Isolation
A single fault in a high-voltage battery can potentially expose you to electrical shock. But the battery management system prevents this by isolating the faulty circuit. It monitors a wide range of parameters—cell voltages, temperatures, currents, and internal resistance—to detect and isolate anomalies.
Different Battery Management System Types
External or internal installations are possible for battery management systems. Let’s examine each’s benefits and drawbacks.
Internal Control System for Batteries
The battery pack itself has an internal BMS built right in. It follows that the BMS is integrated into the battery case, from which it operates to continuously monitor and control the operation of the cells.
Benefits: Since there is no need for extra wire or external components, this conserves space.
Due to its integration with the battery, it can provide accurate control and monitoring for peak efficiency.
Additional installation and upkeep are not necessary. Additionally, users are relieved of the burden of connecting external BMS components.
Cons: It needs to be changed whenever the battery needs to be changed.
Note: The inbuilt BMS of Battle Born Batteries keeps track of every single cell within the battery pack. It determines the maximum amount of current that can be introduced and removed without endangering the battery. The batteries are always guaranteed to run within a safe range by our integrated BMS. When the BMS detects harmful operating circumstances, the battery is cut off.
System for External Battery Management
A BMS that is external to the battery pack is a stand-alone device. Through wiring harnesses, it is able to monitor and control the operation of the battery cells. Larger battery systems and specialized configurations frequently need an external BMS.
Benefits: An external BMS offers flexibility. It enables customers to select and alter BMS units in accordance with their needs.
An external BMS may be easily upgraded or replaced without compromising the battery pack.
More sophisticated functions like data logging and remote monitoring are available in certain external BMS systems.
Cons: It’s difficult to install and could be difficult for novice users.
Extra room is needed for external BMS units.
You also need to purchase expensive hardware in addition to the battery pack.
How to Select and Operate a Battery Management System
It can be risky to use a battery without a management system. Your battery is not protected from overcharging or overheating without it. Additionally required for ongoing monitoring is a BMS. Therefore, even while skipping the BMS can seem handy, doing so could end up costing you more in the long run.
Battery management systems come in a variety of options and setups. You can select and operate a BMS more skillfully if you follow these pointers and instructions. First, be aware of the particular needs your batteries require. For instance, you might not require a BMS if your battery is lead-acid. But lithium-ion batteries require a BMS.
Accurate voltage monitoring, temperature regulation, and protection against overcharging and overdischarging are all essential functions of a good BMS. Recall that battery chemistry can also be harmed by low temperatures. In order to keep the battery from being charged or drained when it becomes too cold, a BMS should feature a low-temperature cut-off.
Seek features that are appropriate for the voltage levels of your battery and that correspond to its requirements. You’ll need a strong BMS if your batteries require regular cycles of charging and discharging as well as dependable power delivery. That is, one made to withstand the highest possible voltage and current.
Selecting battery management systems from reliable manufacturers with a track record of safety is important because a BMS is an expensive investment. If you purchase an external BMS, think about hiring an expert to install it. Inaccurate readings might be caused by a bad installation. Additionally, it may impair battery performance and safety.
Lastly, certain battery management systems provide Bluetooth or mobile connectivity for distant connections. This is useful if you require continuous monitoring due to high battery usage.
Select Maxworld Batteries for Optimal Battery Functioning
Lithium-ion batteries must be used with a battery management system. It is a reliable safeguard against potentially hazardous battery malfunctions. However, an external BMS may be expensive. Why not go with an integrated BMS that costs nothing extra?
Around the globe, Maxworld Batteries power off-grid solar systems, boats, trucks, and RVs. Our selection of LiFePO4 batteries with integrated BMS is sure to provide you with exceptional and dependable performance. Furthermore, our batteries are simple to install and maintain, lightweight, strong, and safe. Free shipping, a financing option, a 5-year guarantee, and technical support are examples of extras.