How to Build the Right Tech Stack for Battery Energy Storage

However, not all tools are the same. Some, like the battery management system (BMS) or energy management system (EMS), are built into the BESS itself by the manufacturer or integrator and are essential for baseline operation. Other tools sit on top of this base layer and offer more advanced capabilities, such as analytics, or revenue optimization software. These are often sold separately by third parties, which means operators must navigate a fragmented vendor landscape when choosing what to use.  

This guide was created to bring clarity to that landscape. It breaks down the key components of a BESS tech stack, from foundational systems like the BMS and EMS to add-on tools like analytics, asset performance management and optimizers. For each type of tool, we explain what it does, where it fits in the system, and what its limitations are, helping you understand what you already have, and what you may still need.

Whether you're just starting to plan your first BESS project, or already running one, this guide is for you. It will help you evaluate your current tools, discover any gaps, and learn about new solutions. If you're new to the industry, this is a practical starting point for understanding the technology landscape.

Basic Built-in BESS Tools

Every BESS comes with a basic set of built-in tools. These are non-negotiable and handle core tasks such as monitoring, control, conversion, and protection. Together, they form the essential software and hardware needed to keep the system running in all conditions.

Our infographic on the BESS tech stack visualizes the tool ecosystem:

Download the infographic here.

‍

Battery Management System (BMS)

Core Functions

The Battery Management System (BMS) keeps a BESS safe and healthy. It continuously monitors battery cells to track voltage, temperature, current, and State of Charge (SoC) at the module or pack level. The BMS balances charge across cells to prevent uneven wear and protect capacity. A BMS is embedded inside the battery enclosures at the cell, module, or string level.  

The BMS also enforces safety limits and manages battery behavior in real time. For example, a BMS may detect a rapid voltage drop in a group of cells and trigger an automatic shutdown of the module to prevent cascading failure. This helps prevent system failures and supports warranty compliance.

A typical BMS consists of a main Battery Control Unit (BCU) and several subunits called Battery Management Units (BMUs). BMUs monitor individual cells, while the BCU oversees the entire system and estimates SoC.  

Operators use BMS to review reports and act on safety-critical events. However, the BMS is usually just one part of a larger system that also includes the EMS and the Supervisory Control and Data Acquisition (SCADA) tools.

Limitations

A BMS is an invaluable monitoring tool, but it is not without shortcomings. Conventional BMS often miss cross-module or rack-level imbalances, which can impact performance and availability. They also tend to provide inaccurate estimates of battery states. Unlike BESS analytics, a BMS is only designed for real-time monitoring. While a BMS can trigger alarms, it can’t pinpoint exact causes or use historical data to predict future failures.

Fire Control and Alarm Panel

Core Functions

Fire is a constant risk in BESS. Overcharging, damage, or electrical short circuits can cause lithium-ion batteries to overheat and trigger a thermal runaway event that can spread to adjoining cells.  

The complexity of BESS environments makes it difficult to detect thermal events. While the BMS constantly monitors issues such as overcharging, over-discharging, and overheating, it is not enough to prevent fires. A layered safety approach is considered best practice.

Dedicated fire detection systems and suppression controls are essential for safety in BESS containers or enclosures. These systems use sensors to detect heat, smoke, or flammable gases. If sensor readings surpass safe limits, alarms and display panels issue alerts. Many fire control devices also include automatic suppression that releases inert substances, aerosols, or water-based agents to extinguish fires. Fire control systems are typically placed in an auxiliary control room or built into a container wall. Usually, these tools will be connected to the site-wide SCADA systems, which handle event logging, ventilation, and emergency shutdowns.  

Fire control and alarm systems are also required for code compliance and insurance coverage.

Limitations

Fire control and alarm systems are purely reactive and can only detect a fire after thermal runaway has begun. In some cases, standard suppression isn’t enough, and fires can re-ignite hours or even days later. Hardware failures or defects can also decrease the system’s effectiveness.  

Power Conversion System (PCS)

Core Functions

The Power Conversion System (PCS) controls the two-way flow of energy in a BESS. It converts Direct Current (DC) into Alternating Current (AC) so BESS can feed energy into the electrical grid. It also converts AC back into DC to charge the BESS with surplus electricity. By using advanced algorithms, a PCS reduces losses during the energy conversion process. PCS can be housed in a separate power electronics container.

The PCS also helps control voltage and frequency and provides reactive power support. In most cases, a PCS will work with the EMS to improve BESS efficiency during peak periods and to keep the system running during disruptions.  

In the event of a blackout, the PCS can perform a black start, allowing the BESS to restore power without relying on the main grid. During grid disruptions, the PCS also handles islanding detection, ensuring the BESS disconnects safely and reconnects when the grid is stable again.  

When brief voltage drops occur, the PCS supports voltage ride-through to keep the BESS running. In weak or off-grid setups, the PCS helps set and stabilize voltage and frequency through its grid-forming capabilities.

Limitations

PCS tools can struggle to effectively maintain stable voltage levels or evenly balance battery loads. Since they generate significant heat, PCS tools often require additional cooling systems and ventilation. Moreover, since they rely on complex firmware and communication interfaces, PCS units are particularly vulnerable to cyberattacks or software malfunctions.  

Energy Management System (EMS) / Supervisory Control and Data Acquisition (SCADA)

Core Functions

The Energy Management System (EMS) is a combination of software and hardware tools that controls how a BESS charges and discharges based on grid conditions, energy demand, and supply. As a primary control and execution system, the EMS is often referred to as the ‘brain’ of a BESS.

The control logic of an EMS comes from a constant flow of real-time information on battery voltage, temperature, current, and SoC. Based on this data, the EMS directs energy flow and anticipates load demand.

If the EMS is the brain, then the Supervisory Control and Data Acquisition (SCADA) system acts as the nervous system. The SCADA gathers real-time data from field devices such as the BMS, PCS and fire panels, then shares that data with the EMS and operators through dashboards and control interfaces.  

While SCADA focuses on monitoring and low-level controls, the EMS decides what to do and when. The EMS then issues high-level commands, such as charge/discharge setpoints, that SCADA transmits to the relevant hardware.

These tools typically work together, either via a centralized control or through cloud-hosted interfaces. For example, if frequency drops suddenly, the EMS may curtail charging to help stabilize the system. SCADA then ensures that commands are delivered in real time and executed by inverters or relays.

Together, EMS and SCADA provide the backbone for safe, efficient, and automated BESS operation.

Limitations

EMS/SCADA systems must constantly communicate with multiple subsystems. This makes integration complex, delays response times, and increases the risk of data errors. Many platforms lack capabilities like predictive maintenance, state-of-health diagnostics, lifecycle forecasting, or warranty tracking. Due to their role in controlling and monitoring grid assets, EMS/SCADA tools are common targets for cyberattacks. Some legacy systems may not have strong cybersecurity protections. They may also struggle to process increasing data volumes in real time.  

Historian

Core Functions

Historian systems collect, store and retrieve time-series data. Rather than collecting data directly from sensors, a historian receives real-time data from SCADA, EMS or control systems, such as voltage, current, temperature, SoC, State of Health. This data originally comes from devices like the BMS or PCS. Historians can be deployed either onsite or in the cloud.  

This historical data is crucial for analyzing and reporting BESS performance, scheduling predictive maintenance, and meeting regulatory requirements. The historian ensures that operators can track KPIs and confirms that the BESS is performing as expected and staying within warranty.  

Technically speaking, a historian is not required to operate a BESS. However, without a historian, it is more difficult to maintain safety, reliability, compliance, and performance. That’s why most commercial and utility-scale BESS operations will incorporate a historian system in their tech stack.  

Limitations

Integrating historians with existing BESS can be highly complex. Compatibility issues with other software may degrade the accuracy and reliability of the analysis provided by a historian. These tools also may not be adequate for processing large volumes of high-frequency telemetry data. If a third-party controls dispatch, historian logs may miss the full context or intent of dispatch decisions, making it hard to understand how those decisions affect performance or warranty compliance.

BESS Tools to Enhance the Basic Stack

Alongside these essentials, several tools can further enhance the value, reliability, and lifespan of a BESS. Optimizer tools, BESS analytics, and Asset Performance Management (APM) tools are all especially useful in commercial or utility-scale deployments.

Optimizer Tools

Core Functions

BESS optimizer platforms complement core BESS systems such as the BMS and EMS. Optimizer tools are intelligent software designed to boost performance, revenue generation, and operational decision-making.  

Optimizers use real-time and forecasted data, such as market prices, load, and weather conditions to schedule BESS operations. These tools ensure the BESS operates in the most efficient way.  

An optimizer uses forecast data to calculate the most profitable or effective dispatch plan. For example, based on historical data, the optimizer may ask the EMS to discharge 1 MW from 5 to 6 PM to reduce peak demand charges. The EMS first checks that there is enough SoC and that the PCS are ready. If everything is in order, the BMS then confirms that the battery temperature and voltage are within acceptable limits before allowing the discharge.  

Limitations

Because they rely on simplified models, some optimizers may overestimate performance and underestimate losses. They often miss key factors like thermal dynamics and detailed degradation mechanisms. Optimizer tools may also respond poorly to real grid dynamics or intermittent fluctuations.  

Asset Performance Management (APM)

Core Functions

Asset Performance Management (APM) help BESS operators visualize asset health and performance trends. APMs feature integrated dashboards, graphs, charts, and interactive interfaces that show the health and performance of the BESS. They typically gather data from BMS, EMS, and SCADA tools. This visual context may help operators with decision making, but there are limits to what APMs can do.  

Limitations

APMs are not built for BESS. They cover all renewable assets and are typically unable to cope with the volume and frequency of data generated by a BESS. Most general APM tools don’t have the depth or features needed to fully manage and operate BESS effectively.

In general, APMs do not offer root-cause analysis recommendations. They also lack advanced analytics such as Round-Trip Efficiency (RTE), resistance, or an accurate SoC. Most APMs don’t include dedicated warranty tracking either. To turn data visualization into actionable insights, APMs must be coupled with advanced BESS analytics.

BESS Analytics

Core Functions

BESS analytics tools provide deeper insights than EMS, BMS, and APMs alone. They analyze BESS performance, usage patterns, degradation, and efficiency.  

BESS analytics helps operators make more informed operational decisions by adding context to the raw data. This supports more proactive maintenance planning and helps maximize asset value over the system’s lifespan.

During commissioning, BESS analytics can pinpoint weak spots and establish baseline performance. Once the system is running, they help track KPIs and ensure that performance aligns with expectations.  

By analyzing real-time and historical battery data along with physical and operational constraints, BESS analytics can accurately estimate usable energy. They can also identify usage patterns that impact longevity and recommend operational adjustments.  

Limitations

BESS analytics are only as accurate as the data they receive. Poor sensor calibration, proprietary data formats, data gaps, and restricted access to BESS data can reduce accuracy. To get the most value from BESS analytics, it is important to ensure access to your data early in the planning process.  

Finding the Right Tech Stack Balance for Your BESS

Effective energy storage management depends on more than just hardware — it requires the right software to turn complex data into clear, actionable insights. With the right tools, operators can strike a balance between maximizing performance, minimizing degradation, and reducing downtime.

TWAICE supports this effort with advanced analytics purpose-built for utility-scale BESS operations. By going beyond the capabilities of EMS and SCADA systems, TWAICE helps asset owners and operators improve reliability, extend asset life, and unlock greater value. It also makes day-to-day operations easier by giving teams the tools they need to work more efficiently and make smarter decisions.

‍

To see how TWAICE can strengthen your BESS tech stack, explore a live demo!