News & FAQ

Two different liquid electrolytes for the negative and positive electrodes are stored in separate tanks and circulated through two half-cells where the electrochemical reactions for charging or discharging take place. The electrical power is determined by the electrode material and the electrode surface area in the cells. The assembly of several cells results in the energy converter unit, the so-called stack. At the electrodes, the electric potential and voltage are generated through interaction of the two electrolytes. In order to avoid mixing of the electrolytes, the half-cells are separated by a membrane. The membrane is only permeable to certain ions and ensures the charge balance in the electrolytes. Under electrical load the battery supplies energy. To charge the battery, a power source is connected and the reaction in the half cells proceeds in the opposite direction.

Our Organic Flow Battery can be used flexibly throughout the entire energy value chain. They are particularly suitable for stationary energy storage, since the storage capacity is decoupled from the electrical power unit and therefore can be scaled up independently of it. The storage capacity of the battery can simply be adjusted by choice of the tank size and the amount of stored electrolyte. Other advantages are the long life cycle time and the absence of rare heavy metals. No self-discharge takes place in the tanks. Since they are neither flammable nor explosive, Organic Flow Batteries provide a high level of safety during operation for equipment, personnel and environment. The complete value chain can be realized locally and the raw material basis is secured long-term.

Unlike other redox flow batteries, which use solutions of metal salts as electrolytes, the electrolytes of our Organic Flow Technology are based on natural, renewable raw materials and can therefore be seen as a renewable storage technology. All electrotechnical components in the energy converter have been adapted to the electrolyte and optimized for cost-efficient mass production.

An organic electrolyte from the natural source lignin, which is available in almost unlimited amounts, is used as storage medium. Lignin derivates are obtained very cost-effectively from the waste streams of existing paper and pulp mills. The resulting organic electrolytes are used as an aqueous solution in the Organic Flow Battery.

Today, this raw material is available on an extremely large industrial scale, but due to the lack of commercial utilization it is mostly incinerated. In order to produce electrolytes from lignin, no raw material imports from unreliable sources are necessary, but the existing infrastructure of the pulp and paper industry can be used. The complete value chain can be realized locally and no tight or finite resources have to be utilized. More information can be found at Organic Electrolytes.

Freely scalable means that the required electrical power (kW) or storage capacity (kWh) can be chosen to fit the specific application. These two parameters are independently selectable due to the modular configuration. More information can be found at Technology.

Because Organic Flow Batteries are a storage technology with external storage, the electrical power and storage capacity of the battery can be scaled independently. The amount of electrolyte or the size of the tanks determines the battery capacity (amount of storable capacity). The size and number of stacks determines the battery power (maximum electrical current during charging and discharging).

Organic Flow Batteries can reach a very long service life and offer a high stability during thousands of cycles of charging and discharging. Moreover, the stored electrolytes lose no capacity due to the spatial separation between storage and power units.

The Organic Flow Technology is highly environmentally friendly. For the production of the electrolytes no trees are felled additionally and no particularly tight or finite resources are consumed. Lignin is a renewable resource and is formed in existing pulp production in very high quantities. It is sufficiently available for use of Organic Flow Batteries for the global integration of renewable energies and charging infrastructure. The electrolyte can also be recycled or regenerated after the product life cycle.

A successful energy transition necessitates terawatts of storage capacity worldwide. Only with the support of very large storage capacities the share of wind and solar energy in the electricity mix can be further increased and CO₂-emissions can be reduced. So far, rare metal compounds are typically used for chemical energy storage. However these are not available in these required large quantities, and are very expensive or ecologically questionable. The renewable raw material lignin used for organic storage molecules is produced in the pulp and paper industry in a million-ton scale. Virtually all future storage demand scenarios can be met with these lignin quantities.

No. The Organic Flow Battery is a large-scale energy storage system with a power of 100 kW per unit. Due to this scale, it can not be used as a home storage solution. However, it can serve as joint solution for a residential neighborhood as a shared storage system (e.g. district storage).