Beyond Battery Management System: The Future of Battery Technology
Any electrified equipment requires batteries. Only lithium (Li) ones have the capacity to power industrial and commercial applications. However, with great power also comes great responsibility.
While Li-ion battery packs have many advantages — they’re more efficient, charge faster, and have a longer lifespan — they’re also expensive to produce, complicated to integrate into products, and fraught with safety issues if not handled properly.
That’s why most battery packs come with a battery management system (BMS) to help manage the batteries’ performance and ensure safe operations. Here’s what you need to know about BMS, why it’s important, how it works, and what the future looks like for advanced battery management.
What is a battery management system?
The most rudimentary BMSs do nothing more than disconnect the battery if it’s at a clear risk of overcharging, over-discharging, or overheating. Many are used in low-quality power tools and discount-store toys and are often linked to battery incidents (e.g., fires.)
“Real” BMSs act as a battery pack’s brain to regulate a cell’s charging and discharging activities. Some also track the batteries’ performance and state of charge (SoC) while ensuring they operate within their safety margins.
Some essential functions of a typical BMS include:
Monitor a battery pack’s characteristics, including voltages, temperature, capacity, power consumption, remaining charge/operating time, and charging cycles.
Control the cells’ behaviors to optimize their performance and lifespan.
Prevent temperature extremes that can lead to thermal runaway and inextinguishable fires.
Protect a battery from damaging circumstances such as high currents, deep discharge, over-voltage, and extreme temperature variations.
Ideally, a BMS also balances multi-cell batteries to ensure that the cells have the same charging and discharging requirements to enhance longevity and reliability.
The importance of battery management systems
A BMS ensures the optimal functioning of a battery pack. It monitors each cell and identifies issues before they impact the safety and performance of the equipment.
It protects the battery cells from damages caused by overcharging or over-discharging. It performs charge balancing among individual cells in a pack to ensure that each cell functions at its maximum capacity. But not all BMSs achieve this objective in the same way.
Simple BMSs burn off excess energy in the “stronger” cells, so they are all equally weak. This method is safe but inefficient. More advanced BMSs perform charge redistribution, siphoning power from stronger cells to weaker ones. They also check for unsafe conditions, such as loose connections and internal shorts, and shut down the battery pack as needed to protect the equipment and users.
Additionally, a robust BMS helps operators maximize cost efficiency. Lithium and other elements like cobalt are expensive and finite resources — the mining process is costly and has profound environmental and societal impacts. Effective resource/asset management lowers the total cost of ownership and makes electrification commercially viable and profitable at a global scale.
How does a battery management system work?
A BMS consists of a series of circuits and electronics. It monitors each cell and regulates the current entering and leaving the cells to optimize performance. By minimizing the overdrawing or overcharging of the battery, a BMS prevents the cell voltages from getting too high or too low to avoid damage and increase the battery’s lifespan.
It measures key metrics such as current, voltage, temperature, and coulomb count to assess the battery’s health and adjust operations accordingly:
When the operator sees a drop in cell voltage at a given load, it can trigger a maintenance procedure so a technician can check for issues such as dry-out, corrosion, or plate separation before the equipment ceases to operate, leading to costly unplanned downtime.
A sudden increase in temperature could be a sign of a thermal runaway event. The BMS can stop the charging and discharging process and alert the operator to perform a safety check.
A BMS can estimate its available capacity by measuring the energy entering and leaving the battery in a charge/discharge cycle. It can alert the operator before the battery is drained and shuts down.
More advanced systems also come with a microcontroller that gathers and assesses information from the sensing circuitry. The sophisticated algorithms enable the BMS to make real-time decisions based on the data collected to optimize performance and ensure safety.
Key functions of a battery management system
BMSs have various features to meet different functional, safety, and cost requirements. Here’s what most offer:
Monitor and determine the SOC at the cell and pack level.
Balance cells by communicating with the controller.
Measure and interpret voltage, current, and temperature signals.
Run diagnostics and display alerts of potential issues.
Shut down the battery when cells behave outside of the safety parameters.
Today’s BMS Technology is just the beginning
Current BMS technologies are a good start but not enough to support electrification at a commercial and industrial scale cost-effectively. Their features and functionalities are just a glimpse of what’s possible for software-defined battery systems.
The Tanktwo Battery Operating System (TBOS) not only enables operators to monitor and manage the SoC and state of health (SoH) of individual cells and battery packs. The software also allows for a “two-way conversation” where operators can adjust the behaviors of each cell based on real-time telemetries to optimize lifespan and performance with a few clicks of the mouse without accessing the hardware.
By changing a few parameters on a screen, you can remotely reprioritize characteristics such as operating costs, reliability, safety, performance, longevity, and more to meet the requirements of individual applications at any given moment.
Also, our software-defined battery technologies allow cells to charge from and discharge/output at any voltage. Product builders and operators can configure battery packs (and even mix and match cells with different chemistries) to produce any voltage needed on the fly to meet the requirements of multiple applications.
As such, they can stock just one or a few types of cells and have infinite flexibility in their implementation to achieve unprecedented scalability while safeguarding their businesses against supply chain fluctuations.
Last but not least, our vast database and predictive analytics capabilities help each battery pack learn from similar solutions. They can forecast remaining useful life, required maintenance intervals, and potential problematic behaviors to optimize performance and streamline maintenance to maximize operational efficiency and profitability.
