For tomorrow.
For the climate.

With VoltStorage's storage systems based on ecological redox flow technology, power from renewable energy sources can be used in a sustainable way around the clock, regardless of the weather - for a more climate-friendly future.

Storing renewable energies ecologically

Optimizing self-consumption of self-produced power from renewable energies, avoiding expensive power load peaks or creating a reliable emergency power supply – the reasons for investing in a storage solution for renewable energies are many and diverse. Currently, storage systems based on lithium technology dominate the market, but in many aspects they are questionable from an ecological point of view. The redox flow storage technology represents a sustainable, resource-saving and thus future-oriented alternative for storage systems, and also has a high level of operational reliability with optimal performance.

Why battery solutions beyond lithium are needed

The most common type of lithium battery is composed of five raw materials: lithium, nickel, manganese, cobalt and graphite. Above all, the extraction of lithium and cobalt causes massive ecological and humanitarian problems. The situation is different for energy storage systems based on redox flow technology. The resources required for this technology can be obtained without overexploitation of man and nature.

Lithium mining threatens ecosystems

The largest lithium reserves are located in one of the most water-poor regions of South America. The lithium dissolved in groundwater is pumped to the surface and enriched with fresh water. The evaporation of water leaves a green lithium-containing liquid behind. As there is little rainfall in the region, the water reserves cannot recover from the lithium mining. As a result, water scarcity threatens the local population and biodiversity.

Lithium batteries use conflict materials

The conflict material cobalt is largely required for the production of lithium battery cells. The world’s largest production volumes come from Congo, where tens of thousands of workers, mostly barefoot, make cobalt mining possible in often unsecured and steeply sloping shafts. The precarious working conditions mean that the lives of the workers are at great risk, especially during the rainy season, when the unsecured corridors and earth shafts collapse.

10.65 TWh
are needed to power 100% of the USA by batteries
for 24 hours.

of the annual lithium production volume would be needed to provide this amount of electricity from lithium batteries alone.

The ecological alternative to lithium: Redox flow storage technology

Compared to common storage technologies, such as those based on lithium, redox flow technology is highly climate-friendly, as it does not require rare materials or conflict raw materials, is fully recyclable, and also has a very high level of operational reliability and a long lifetime.


The storage medium is a liquid electrolyte. This is located in two separate tanks and can take on different oxidation states through a redox process, thereby storing energy.


The electrolyte flows through the battery cells in two separate circuits. When the battery is charged, the electrolyte is reduced in the negative half cell and oxidized in the positive half cell. When discharging, this process is reversed again.


A special pump system flows the electrolyte into and through the battery cells. This makes it possible that not all the electrolyte has to be kept in the cells, enabling the decoupling of energy capacity and power. The pumping system is only activated on demand.

Advantages of redox flow technology


For the development of storage systems based on redox flow technology, no rare raw materials or conflict raw materials are used, the extraction of which is often accompanied by overexploitation of humans and nature and associated impacts on the ecosystem.

100% non flammable

Operational reliability plays a major role in energy storage. In this regard, redox flow technology offers decisive advantages over other storage technologies: The electrolyte consists exclusively of non-flammable components – including a very large proportion of pure water.


With the redox flow technology, we rely on a proven CO2-reducing and climate friendly battery technology. Thanks to the ecological redox flow storage technology, power from renewable energies can be used around the clock and actively contribute to combating climate change.

VoltStorage - Shaping the futire of energy storage

With our multi-technological approach, we create pioneering battery solutions without the use of lithium. In doing so, we rely on two resource-conserving, cost-effective and climate-friendly storage technologies: With vanadium redox flow technology, we are relying on a proven and tested technology to enable commercial customers to cover their energy needs during periods of low wind or low sun. In addition, our international research and development team is working on iron salt technology, which is a revolutionary technology for the energy storage of the future due to its unrivaled low cost and particularly high temperature resistance.

Vanadium redox flow technology

The vanadium redox flow technology was developed by the US space agency NASA in the 1970s. With its international team of experts, VoltStorage has taken this resource-saving storage technology to a new level in recent years.

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Iron salt technology

The iron salt technology is destined to shape the future of battery storage beyond lithium, because of the widely available and low-cost iron-based storage medium.

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