Designing Energy Storage That Works as Hard as the Grid

The growth of renewable energy has added a new layer of complexity to power grid infrastructure. Unlike fossil-fuel generation, solar and wind are intermittent, often peaking when demand is low and falling short when it’s high. To make renewables viable at scale, utilities and large commercial operations are turning to Battery Energy Storage Systems (BESS) to smooth out fluctuations, enhance grid resilience, and allow for energy trading.

Every BESS consists of a network of semiconductors that handle everything from battery monitoring and safety to power conversion and system control. As demand for larger, more efficient, and more reliable storage grows, semiconductor innovation is becoming critical to modern energy systems.

The Market is Scaling, Fast

Energy storage is not a niche application. BloombergNEF forecasts that global BESS deployments will exceed 400 GW/1,194 GWh by 2030. The U.S., China, and Europe are leading the charge with a mix of grid-scale and commercial installations, driven by aggressive decarbonization targets, grid modernization programs, and economic incentives.

As systems scale from hundreds of kilowatt-hours to multi-megawatt capacities, complexity rises exponentially. Engineering teams are tasked with improving power density, reducing system losses, and meeting strict safety standards—often within aggressive design cycles.

System Complexity Starts with the Battery

While batteries may seem like static components, the truth is they are dynamic and fragile electrochemical systems. Keeping them balanced, cool, and within safe voltage and temperature ranges is crucial. A Battery Management System (BMS) is responsible for this—monitoring individual cells, equalizing charge levels, and protecting against over-voltage, short circuits, and thermal runaways.

In large-scale BESS deployments, the BMS must handle hundreds or even thousands of cells in real-time. It must also communicate seamlessly with system controllers and, increasingly, integrate with cloud-based energy management platforms for diagnostics and optimization.

This is where advanced BMS ICs come into play.

A Scalable Approach to Cell Monitoring

One standout solution for high-voltage battery monitoring is Infineon’s TLE9018 series—a BMS transceiver IC designed specifically for scalable lithium-ion battery systems. It enables robust, high-speed communication between multiple monitoring units over a differential daisy-chain interface.

Key engineering advantages include:

• High Channel Count: Each TLE9018 can interface with up to 12 cells, allowing designers to easily expand monitoring capabilities without redesigning the system.

• Robust Communication: Built-in error detection, wake-up functions, and support for multiple redundant paths enhance safety and reliability in noisy environments.

• Low Latency: Real-time cell voltage and temperature data enable fast system response to faults or load changes, which is essential for grid services applications.

Paired with Infineon’s analog front ends (AFEs) and microcontroller units (MCUs), the TLE9018 simplifies the architecture for modular BESS systems while meeting IEC 61508 and ISO 26262 safety requirements.

Is Power Conversion the Real Hero?

While batteries store energy, it’s the power conversion system (PCS) that makes it usable. Energy needs to move bi-directionally between the grid and batteries, often requiring transformation between AC and DC, voltage stepping, and current regulation. The PCS also interfaces with grid frequency signals, demand response platforms, and protection relays.

A modern PCS for BESS includes:

• Bidirectional inverters (often using silicon carbide or high-voltage silicon MOSFETs)

• DC/DC converters for balancing or interfacing sub-packs

• Isolation components, gate drivers, and current sensors

Efficiency is king. Every percentage point of loss is magnified at scale, not only wasting energy but also increasing cooling requirements and reducing ROI.

SiC and GaN Are Shifting the Power Conversion Game

Wide-bandgap semiconductors like silicon carbide (SiC) and gallium nitride (GaN) are redefining what’s possible in BESS design. With higher breakdown voltages, faster switching speeds, and lower losses, they enable more compact, efficient converters.

Infineon has been a leader in this space with its CoolSiC™ MOSFETs and gate driver ICs, which have seen adoption in both utility-scale and commercial BESS deployments.

Key benefits include:

• Higher Operating Frequency: Reducing the size of magnetic components and passive filters.

• Lower Switching Losses: Enabling higher power densities and smaller heatsinks.

• Improved Thermal Management: Allowing systems to run cooler or at higher ambient temps.

For example, a 1 MW BESS inverter built with SiC can offer over 98% efficiency, reducing energy losses and helping meet strict grid interconnection standards like IEEE 1547 and UL 1741.

Integration is the New Differentiator

Semiconductor companies like Infineon are not just offering standalone components anymore—they’re creating platforms. These platforms combine sensing, control, and power stages into optimized reference designs, complete with firmware and safety documentation. The result is faster time to market and reduced engineering risk.

Infineon’s Modular Battery Management System approach, for instance, combines the TLE9018 with ASIL-D capable controllers and functional safety libraries, offering a plug-and-play path to scalable energy storage monitoring.

Similarly, their HybridPACK™ Drive and EiceDRIVER™ family offer integrated solutions for power stages, reducing board space and simplifying thermal design.

Key Design Considerations

When developing or upgrading a commercial or utility-scale BESS, electrical engineers should weigh the following:

1. Scalability: Does your BMS or PCS architecture allow you to move from 100 kWh to 10 MWh without major redesigns?

2. Communication Robustness: How resistant is your data path to EMI, voltage transients, or single-point failures?

3. Safety Compliance: Are your monitoring and power stages aligned with global safety standards (e.g., IEC 62933, UL 9540)?

4. Efficiency and Thermal Profile: Are you using wide-bandgap components to minimize losses and cooling costs?

5. Time to Market: Can your design leverage proven semiconductor reference platforms and software stacks?

Looking Ahead

As BESS technology becomes embedded in energy markets—from virtual power plants to behind-the-meter applications—the demand for smarter, more efficient, and safer systems will only increase. Semiconductor innovation is at the core of meeting this demand.

With ICs like the TLE9018 and high-efficiency power conversion solutions based on SiC, Infineon is helping design engineers unlock higher performance and flexibility in energy storage applications. As system requirements become more demanding, leveraging these purpose-built semiconductor platforms will be key to staying competitive and delivering reliable energy storage solutions at scale.