Flow Batteries

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Increase Coulomb Efficiency Above 99%

Ionomr has both AEM and PEM options available and in development for use in Redox Flow Batteries (RFBs). Aemion™ prevents transfer of the primary reaction ions which are typically positive – V4+, Fe2+,Na+, etc. This eliminates side reactions and ensures optimal efficiency. The ratio of primary vs. unwanted reactions is called “Coulomb efficiency”. Aemion™ can increase the Coulomb efficiency above 99%, improving the overall system efficiency and significantly decreasing lifetime costs.

Pemion™ is a highly conductive alternative to existing PEM solutions, reducing electrical losses during operation. Its hydrocarbon structure improves the overall recyclability of the system, which enhances one of the major benefits of RFBs over alternative battery systems.

In Redox Flow Batteries, redox refers to the two chemical reactions occurring in the process:
(red)uction and (ox)idation

Reduction: a gain of a negatively-charged electron, decreasing its oxidation # (-1)
Oxidation: a loss of a negatively-charged electron, increasing its oxidation # (+1)

i.e. if the oxidation state is 2+, then the atom has lost 2 electrons

During discharge, an electron is released via an oxidation reaction from a high chemical potential state on the anode of the battery. The electron moves through an external circuit to do useful work. Finally, the electron is accepted via a reduction reaction at a lower chemical potential state on the cathode of the battery. The direction of the current and the chemical reactions are reversed during charging.

Flow batteries may be designed using a wide variety of metals or organic molecules that are able to exist in different oxidation states. The most commonly-used design is vanadium-vanadium, providing simple operation with only one metal. Other examples include zinc-bromine and iron-iron.