Periodic Reporting for period 2 - MeBattery (MEDIATED BIPHASIC BATTERY)
Período documentado: 2023-05-01 hasta 2025-10-31
Flow and static battery technologies currently considered state-of-the-art (such as All-Vanadium, Zinc-Br2, Na-ion and Li-ion) suffer from significant drawbacks in sustainability, recyclability and energy efficiency. To meet surging energy demands and ambitious climate goals sooner, radically different energy storage concepts are urgently needed.
MeBattery strives to lay the foundations of a next generation battery technology relying on a combination of fundamentally new thermodynamical concepts. These have the potential to overcome the critical limitations of previously developed battery systems across the most crucial performance categories.
The project’s core outcome will be a battery prototype envisioned to be energy-dense, eco-friendly and long-lasting and can pave the way for the next phase of the transition to decarbonised and sustainable energy solutions for society.
The overarching goal of the MeBattery project is to lay the foundations of a next-generation battery technology, which will possess an excellent balance among all the key performance indicators. In detail, the following three objectives will contribute to achieving this goal:
- To increase the energy density of a flowing technology system: 50 Ah L-1.
- To increase the battery cycle life by preventing crossover of dissolved species: 99.25 % per 100 cycles.
- To achieve an energy efficiency value above 75 % at 50 mA cm-2.
MeBattery strives to lay the foundations of a next generation battery technology relying on a combination of fundamentally new thermodynamical concepts. These have the potential to overcome the critical limitations of previously developed battery systems across the most crucial performance categories.
The project’s core outcome will be a battery prototype envisioned to be energy-dense, eco-friendly and long-lasting and can pave the way for the next phase of the transition to decarbonised and sustainable energy solutions for society.
The overarching goal of the MeBattery project is to lay the foundations of a next-generation battery technology, which will possess an excellent balance among all the key performance indicators. In detail, the following three objectives will contribute to achieving this goal:
- To increase the energy density of a flowing technology system: 50 Ah L-1.
- To increase the battery cycle life by preventing crossover of dissolved species: 99.25 % per 100 cycles.
- To achieve an energy efficiency value above 75 % at 50 mA cm-2.
The main activities performed and achievements for each of the technical and scientific work packages (WP) are summarized below:
WP1: (1) Development of two computational protocols to predict partitioning coefficient and redox potentials of organic compounds in aqueous biphasic systems. (2) Identification of >30 redox mediators with suitable properties out of >1000 candidates screened computationally. (3) Establish intuitive guidelines for selection of materials of tuned liquid-liquid and liquid-solid interfacial properties.
WP2: (1) Synthesis of a library of Prussian Blue Analogues (PBAs) covering a wide range of redox potentials. (2) Understanding the effect of morphology and size in the redox kinetics of PBA. (3) Synthesis of a library of 84 organic redox compounds covering a wide range of redox potentials for negative and positive electrolytes.
WP3: (1) Identification of 8 biphasic systems thermodynamically viable. (2) Identifying 120 combinations of thermodynamically compatible redox mediator/solid material pairs.
WP4: (1) Development of tools to elucidate self-discharge mechanisms at liquid– liquid interfaces. (2) Development of techniques to select best material pairs for the battery prototypes based on charge transfer reaction at the liquid–solid interface.
WP5: (1) Selection of the 4 most suitable combinations of solid booster-redox mediator-aqueous biphasic systems for the full battery prototypes. (2) Development of an efficient confinement strategy of the solid booster material for better performance than conventional packing methods. (3) Development of two different functional redox mediated flow battery prototypes based on two different approaches.
WP6: (1) Indentifying two redox mediators with low toxicity for both human and environmental organisms. (2) Quantification of the environmental impact of the two major innovations of the MeBattery technology (3) Technoeconomic analysis of MeBattery technologies, conducting sensitivity analyses for the capital cost of power and energy.
WP1: (1) Development of two computational protocols to predict partitioning coefficient and redox potentials of organic compounds in aqueous biphasic systems. (2) Identification of >30 redox mediators with suitable properties out of >1000 candidates screened computationally. (3) Establish intuitive guidelines for selection of materials of tuned liquid-liquid and liquid-solid interfacial properties.
WP2: (1) Synthesis of a library of Prussian Blue Analogues (PBAs) covering a wide range of redox potentials. (2) Understanding the effect of morphology and size in the redox kinetics of PBA. (3) Synthesis of a library of 84 organic redox compounds covering a wide range of redox potentials for negative and positive electrolytes.
WP3: (1) Identification of 8 biphasic systems thermodynamically viable. (2) Identifying 120 combinations of thermodynamically compatible redox mediator/solid material pairs.
WP4: (1) Development of tools to elucidate self-discharge mechanisms at liquid– liquid interfaces. (2) Development of techniques to select best material pairs for the battery prototypes based on charge transfer reaction at the liquid–solid interface.
WP5: (1) Selection of the 4 most suitable combinations of solid booster-redox mediator-aqueous biphasic systems for the full battery prototypes. (2) Development of an efficient confinement strategy of the solid booster material for better performance than conventional packing methods. (3) Development of two different functional redox mediated flow battery prototypes based on two different approaches.
WP6: (1) Indentifying two redox mediators with low toxicity for both human and environmental organisms. (2) Quantification of the environmental impact of the two major innovations of the MeBattery technology (3) Technoeconomic analysis of MeBattery technologies, conducting sensitivity analyses for the capital cost of power and energy.
MeBattery has had tremendous scientific and technological impact, generating significant new scientific knowledge in different topics/disciplines, which has been published in 30 scientific publications in high impact journals, communicated in 61 contributions to scientific conferences and workshops and protected by 3 patent applications. An overview of the main scientific achievements for each topic is given below.
1- Development of new materials
• Discovery of a new molecule with a record low reversible redox potential as potential anolyte for aqueous redox flow batteries after investigating the redox potentials of around 100 phenazine derivatives
• Molecular engineering of a new viologen-derivative with enhanced stability as anolyte for neutral pH aqueous RFB
• Demonstration that non-toxic viologen derivatives can be molecularly engineered, holding great promise as safe anolytes for AORFB
• Molecular engineering of a new family of aryl-viologen derivatives with unprecedented stability as anolyte for alkaline RFB
• Preparation of Prussian Blue analogues with different compositions (Cr, Mn), identifying key challenges facing these materials to be used as anode materials and strategies to enhance their performance, stability, and scalability
2- Development and validation of computational methods
• New approach to predict the partition coefficient of redox-active compounds (viologen derivatives) in different aqueous biphasic systems using the COSMO-RS
• New COSMO-SAC parametrization model with improved accuracy for prediction of interaction between compounds
3- Development and validation of fast-screening and operando analytical tools
• Nanoelectrochemical platform for elucidating the reaction between solid active material and dissolved redox species for mediated RFB
• Microelectrochemical analytical tools for accelerated evaluation of the intrinsic electrochemical performance of Prussian-blue analogues
• Identifying key processes responsible for the progressive decay in energy storage capacity in AORFB, enabled by a developed operando technique.
• Static cell to accelerate discovery, scale-up and deployment of new chemistries for RFB
4- Fundamental knowledge and optimization strategies
• Unprecedented aqueous solubility of TEMPO and performance as high capacity catholyte for AORFB
• Thermodynamic strategies to increase solubility of redox active organic molecules and hence energy density in organic RFB
5- Integration of battery systems, components and automatization
• New aqueous biphasic electrolyte system with near neutral pH and low cost offering high efficiency, capacity utilization and stability in a membrane-free RFB
• Automatized rebalancing system to prolong cycle life in alkaline ferrocyanide-anthraquinone RFB
• Non-invasive method to monitor and reverse faradaic imbalance in RFB to recover the capacity loss, extending the battery lifetime
• Confinement method of solid capacity booster powder as monolithic structures for better battery performance in a redox mediated RFB
6- Demonstration of new battery concepts and prototypes
• First Zn hybrid membrane-free battery with two immiscible aqueous electrolytes achieving stable cycling performance under real flowing conditions
• High-stability aqueous membrane-free flow battery based on aqueous biphasic system with enhanced electrolyte properties
Key exploitable results have been protected by filing 3 European patents in the duration of MeBattery and one national patent being in preparation and to be filed after the project’s end.
• EP24382687 – “Electroactive compounds”, R. Rubio-Presa, E. Ventosa, R. Sanz, Priority date: 25/06/2024. Extended to: PCT/EP2025/067641 “Electroactive compounds” Universidad de Burgos. Priority date: 25/06/2024
• EP25382932.9 “Redox flow battery”. Holder: Universidad de Burgos. Priority date: 08/09/2025
• EP25383177.0 “Redox flow biphasic battery with separator”. Holder: Fundación IMDEA Energía. Priority date: 30/10/2025
1- Development of new materials
• Discovery of a new molecule with a record low reversible redox potential as potential anolyte for aqueous redox flow batteries after investigating the redox potentials of around 100 phenazine derivatives
• Molecular engineering of a new viologen-derivative with enhanced stability as anolyte for neutral pH aqueous RFB
• Demonstration that non-toxic viologen derivatives can be molecularly engineered, holding great promise as safe anolytes for AORFB
• Molecular engineering of a new family of aryl-viologen derivatives with unprecedented stability as anolyte for alkaline RFB
• Preparation of Prussian Blue analogues with different compositions (Cr, Mn), identifying key challenges facing these materials to be used as anode materials and strategies to enhance their performance, stability, and scalability
2- Development and validation of computational methods
• New approach to predict the partition coefficient of redox-active compounds (viologen derivatives) in different aqueous biphasic systems using the COSMO-RS
• New COSMO-SAC parametrization model with improved accuracy for prediction of interaction between compounds
3- Development and validation of fast-screening and operando analytical tools
• Nanoelectrochemical platform for elucidating the reaction between solid active material and dissolved redox species for mediated RFB
• Microelectrochemical analytical tools for accelerated evaluation of the intrinsic electrochemical performance of Prussian-blue analogues
• Identifying key processes responsible for the progressive decay in energy storage capacity in AORFB, enabled by a developed operando technique.
• Static cell to accelerate discovery, scale-up and deployment of new chemistries for RFB
4- Fundamental knowledge and optimization strategies
• Unprecedented aqueous solubility of TEMPO and performance as high capacity catholyte for AORFB
• Thermodynamic strategies to increase solubility of redox active organic molecules and hence energy density in organic RFB
5- Integration of battery systems, components and automatization
• New aqueous biphasic electrolyte system with near neutral pH and low cost offering high efficiency, capacity utilization and stability in a membrane-free RFB
• Automatized rebalancing system to prolong cycle life in alkaline ferrocyanide-anthraquinone RFB
• Non-invasive method to monitor and reverse faradaic imbalance in RFB to recover the capacity loss, extending the battery lifetime
• Confinement method of solid capacity booster powder as monolithic structures for better battery performance in a redox mediated RFB
6- Demonstration of new battery concepts and prototypes
• First Zn hybrid membrane-free battery with two immiscible aqueous electrolytes achieving stable cycling performance under real flowing conditions
• High-stability aqueous membrane-free flow battery based on aqueous biphasic system with enhanced electrolyte properties
Key exploitable results have been protected by filing 3 European patents in the duration of MeBattery and one national patent being in preparation and to be filed after the project’s end.
• EP24382687 – “Electroactive compounds”, R. Rubio-Presa, E. Ventosa, R. Sanz, Priority date: 25/06/2024. Extended to: PCT/EP2025/067641 “Electroactive compounds” Universidad de Burgos. Priority date: 25/06/2024
• EP25382932.9 “Redox flow battery”. Holder: Universidad de Burgos. Priority date: 08/09/2025
• EP25383177.0 “Redox flow biphasic battery with separator”. Holder: Fundación IMDEA Energía. Priority date: 30/10/2025