Technology
Zinc-Bromine Technology – Structurally
Designed for Safety, Commercial Viability and
Long-Term Stability
Stationary energy storage systems are long-term capital assets with significant regulatory and commercial complexity. Their specific design is decisive: technology, operation and integration must work together reliably over many years.
For this purpose, CAPAC Energy uses Eos’s water-based zinc-bromine technology in the DACH market – developed for storage durations of three to twelve hours and the core applications of modern energy systems.
Six Core Technology Advantages
Six core characteristics determine the performance of zinc-bromine technology. They have a direct effect on commercial viability, safety and day-to-day project operations.
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Long-Term Commercial Viability
Zinc-bromine is designed to deliver stable and predictable storage costs over decades.
- Very low degradation (Z3: no more than 3.6% over 25 years under specified operating conditions)
- Cycle-driven aging rather than temperature-dependent calendar degradation
- Low-maintenance operation without electrolyte replacement or refilling
Outcome
High cost stability as the basis for robust LCOS models.
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Inherent Operational Safety
The water-based chemistry is designed for maximum operational safety.
For this purpose, CAPAC Energy uses Eos’s water-based zinc-bromine technology in the DACH market – developed for storage durations of three to twelve hours and the core applications of modern energy systems.
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Temperature-Stable Operation
The battery is designed for reliable operation across broad outdoor temperature ranges.
For this purpose, CAPAC Energy uses Eos’s water-based zinc-bromine technology in the DACH market – developed for storage durations of three to twelve hours and the core applications of modern energy systems.
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Sustainable Material Base
The technology is based on available, recyclable and conflict-free materials.
For this purpose, CAPAC Energy uses Eos’s water-based zinc-bromine technology in the DACH market – developed for storage durations of three to twelve hours and the core applications of modern energy systems.
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Industrial Maturity
The technology has been extensively tested at industrial scale and validated through accumulated field operating data.
For this purpose, CAPAC Energy uses Eos’s water-based zinc-bromine technology in the DACH market – developed for storage durations of three to twelve hours and the core applications of modern energy systems.
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System Flexibility
Zinc-bromine is designed for variable storage durations and scalable project sizes.
For this purpose, CAPAC Energy uses Eos’s water-based zinc-bromine technology in the DACH market – developed for storage durations of three to twelve hours and the core applications of modern energy systems.
Technology Comparison:
Zinc-Bromine vs. Lithium-Ion
The core advantages described above are not isolated characteristics; they describe the fundamental orientation of zinc-bromine technology. A comparison based on the same six criteria helps put this logic into context.
Not every storage technology is optimized for the same objectives. The differences lie less in individual performance metrics than in the underlying system architecture.
Zinc-bromine (CAPAC / EOS)
Long-term commercial viability
Very low degradation of no more than 3.6% over 25 years (Z3); cycle-driven aging; no electrolyte replacement.
Inherent operational safety
Non-flammable; water-based electrolyte; no thermal chain reaction.
Temperature-stable operation
Operation from -20 °C to +50 °C without cooling or heating technology.
Sustainable material base
Recyclable material base; no lithium, cobalt, vanadium or rare-earth elements.
Industrial maturity
More than 5 GWh of discharged energy; more than 3 million cycles; more than 16 million operating hours.
System flexibility
Storage duration of three to twelve hours; scalable in MW and MWh.
Lithium-ion
Long-term commercial viability
Degradation depends on cell chemistry and operating profile; often more strongly affected by calendar aging; repowering may be required earlier depending on the system design.
Inherent operational safety
Flammable cell components depending on the chemistry; project-specific safety and protection systems required.
Temperature-stable operation
Temperature management often required depending on system design.
Sustainable material base
Dependent on lithium, nickel, cobalt or comparable raw materials.
Industrial maturity
Established in the market with a broad installed base; performance profiles depend on cell chemistry.
System flexibility
Often used predominantly in the one- to two-hour segment; scalability depends on cell and system design.
Outcome
The comparison makes clear that zinc-bromine is consistently designed for long-term stability, inherent safety and multi-hour energy storage – as the structural foundation for commercially optimized battery storage projects. These differences are not matters of detail in individual metrics, but expressions of fundamentally different technology orientations.
How the Zinc-Bromine Battery Works
The differences shown in the comparison result directly from the electrochemical operating principle: zinc-bromine stores energy through a stable, water-based metal-deposition process.
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Basic Electrochemical Principle
During charging, metallic zinc is deposited on an electrode. During discharging, the zinc is dissolved again and electrical energy is released.
- Reversible zinc deposition as the storage medium
- Water-based electrolyte as the reaction environment
- No flammable organic solvents
Outcome:
A physically stable and non-flammable storage process as the basis for inherent operational safety.
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Cell and Module Design
The technical design is optimized for industrial robustness and longevity.
Not every storage technology is optimized for the same objectives. The differences lie less in individual performance metrics than in the underlying system architecture.
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System Impact in the Project Context
The electrochemical operating principle has a direct impact on planning, operation and commercial performance.
Not every storage technology is optimized for the same objectives. The differences lie less in individual performance metrics than in the underlying system architecture.
Contact Us
Discuss Your Project
The choice of storage technology determines the commercial viability, risk profile and regulatory robustness of your project. The key is whether the selected storage solution remains stable, safe and commercially predictable over the long term.
In a structured initial consultation, we clarify:
- Appropriate storage duration (three to twelve hours)
- Commercial sizing (MW / MWh)
- Impact of degradation on your financial model
- Safety and infrastructure concept
- Integration into your specific use case
You receive a robust basis for deciding the technology direction of your battery storage project.
