Redox Reversible Materials for EV Batteries

Redox flow batteries with high energy density by using semi-solid or condensed ion-storing electrode materials that can take up or release ions during operation. The flowable electrode materials are transported between the electrodes to extract energy. This allows using higher concentration electrolytes with improved solubility compared to liquid electrolytes. The flowable electrode materials can be gels, liquids, or solid compounds like oxides, metals, or organic redox couples.

Source

An aqueous organic flow battery with high energy density by combining insoluble and soluble phenazine-based electrodes. The battery uses an insoluble phenazine compound at the negative electrode and a soluble phenazine compound in the negative electrolyte. This allows higher specific capacity and energy density compared to conventional organic flow batteries. The insoluble phenazine compound provides high capacity while the soluble phenazine compound enables high solubility.

Source

Flexible energy storage device with a redox-active biopolymer organogel electrolyte that allows bending without breaking or tearing. The device has electrodes separated by a redox-active biopolymer organogel electrolyte containing a biopolymer gel, redox-active molybdenum ions, and a secondary ionic substance like lithium or sodium. The gel electrolyte allows flexibility at temperatures from -40 to 120°C. The biopolymer gelator, gel solvent, molybdenum ions, and secondary ions are mixed to form the electrolyte.

Source

Battery electrode composition with improved environmental compatibility and recyclability. The composition contains an organic redox molecule with a redox potential between -1.3 and 0.9 V. The redox molecule has peak potentials within 0.8 V of each other. This allows efficient charge storage and capacity retention. The composition can be used in positive or negative electrodes for batteries. It provides high cycling and rate performance, and the redox molecule can decompose into harmless components after battery disassembly.

Source

A high capacity aqueous rechargeable battery with copper ferrocyanide as the positive electrode and phenazine as the negative electrode. The copper ferrocyanide positive electrode provides a high theoretical specific capacity due to the intercalation of multiple metal ions (Cu2+, Fe3+, CN-) during charge/discharge. The phenazine negative electrode has adjustable electrochemical properties from organic redox-active units. The aqueous electrolyte allows for low cost, scalability, and safety compared to organic solvents.

Source

Redox active materials, electrodes, batteries, and methods for improving cathode performance in high capacity, long-life, safe, and cheap energy storage devices using S-linked quinone polymers and sulfurized carbon matrices. The S-linked quinone polymers have quinone redox moieties linked by sulfide groups. They can be homopolymers or copolymers. The sulfurized carbon matrices have sulfur-rich carbon structures. The polymers and matrices provide high capacity, long cycle life, and low soluble sulfur shuttle effects compared to other organic redox materials. They can be combined with additives and used as cathode active materials in non-aqueous electrolyte batteries.

Source

Covalent organic framework (COF) materials for aqueous photochargeable batteries that can directly convert sunlight into stored electrical energy. The COFs have multiple sites for charge separation and redox reactions. They are integrated with interface charge transport materials to construct heterojunctions that regulate photogenerated carrier transport. The COF-based electrodes can directly serve as positive and/or negative electrodes in aqueous photochargeable batteries, enabling efficient solar to electrochemical energy conversion.

Source

Water-based energy storage device using vitamin C as a redox electrolyte that allows reversible charging and discharging without irreversible side reactions. The device uses a cathode made of microporous carbon with a specific surface area of at least 1500 m2/g and pore diameter less than 2 nm. This carbon structure suppresses irreversible reactions during the redox cycling of vitamin C. The carbon cathode allows reversible oxidation/reduction of vitamin C in the aqueous electrolyte, improving the redox reversibility and capacity retention of the device.

Source

Polymer gel-containing materials that can reversibly contract when electricity is applied, and electrochemical devices containing these gels. The gels have a network structure with hydrophilic and hydrophobic sites. They selectively adsorb a second active species through electrochemical redox reactions of a redox pair. This causes reversible contraction as the second species is included. When the redox reaction reverses, the species releases and the gel swells. The redox pair and gel composition allow electrochemical contraction using electricity rather than pumps or gases.

Source

A reversible redox-catalysis covalent organic framework (COF) material for photo/photocatalysis that can efficiently convert solar energy to chemical energy without needing additional reagents or redox pairs. The COF has built-in redox sites that can cycle between oxidized and reduced states. The COF is synthesized by a solvothermal method using specific monomers. The COF can be used as a catalyst in photo/photocatalytic water splitting or CO2 reduction reactions. It shows higher efficiency compared to traditional COFs that require external reagents.

Source

Water system asymmetric supercapacitor with high energy density and wide potential window. It uses redox active materials on the electrodes and in the electrolyte to combine pseudocapacitance and redox capacitance. The asymmetric configuration involves MnO2-coated carbon cloth as the cathode, double-layer Fe2O3-coated carbon cloth as the anode, and redox additives in the electrolyte. This maximizes utilization of the active materials and expands the potential window beyond 2V.

Source

Aqueous polymer electrolyte battery with non-flammable electrolytes and high energy density. The battery uses redox active materials in the electrodes and electrolytes that are soluble in water. The positive electrode (cathode) uses a polymer called neogolite containing a redox center with a large potential difference. The negative electrode (anode) uses a polymer called fosolite containing a redox center with high solubility in water. The neogolite and fosolite are in contact. This allows high energy density and stability because the redox centers have different potentials. The water-based electrolytes are non-flammable. The battery can use solar, wind, hydro power, etc. The scalable design allows expanding storage capacity. The polymer electrolytes can be adjusted for pH and expanded volume. The battery can be connected in parallel

Source

Flexible energy storage device with high energy density, high cycling stability, and good flexibility. The device uses a redox-active polymer hydrogel electrolyte sandwiched between two electrodes. The hydrogel contains a polymer, redox-active metal ions like Co, and balancing anions. The hydrogel provides a flexible, ionically conductive electrolyte for the device. It enables high capacitance, long cycle life, and flexibility compared to liquid electrolytes. The hydrogel forms a uniform film covering the electrodes when soaked in the metal ion solution.

Source

High-performance sodium-ion batteries with metallic sodium anodes, novel cathodes, and electrolytes for applications like electric vehicles. The batteries use a sodium-based metallic anode that is electrodeposited during the first charge cycle. The cathodes are selected from materials that support reversible redox interaction with the disclosed electrolytes. The electrolytes are ammoniate-based with ratios of NH3:salt between 0.1 and 10. The electrolytes support smooth sodium deposition on copper current collectors. The matching electrolyte-current collector couples enable stable cycling of the metallic sodium anode. The cathodes, electrolytes, and current collectors are chosen to balance performance and cost-effectiveness.

Source

Electrochemical devices like redox flow batteries and lithium-ion batteries using isatin derivatives as active materials. The isatin derivatives have bipolar redox behavior in non-aqueous solvents, allowing them to be used as redox materials in both the positive and negative electrodes of flow batteries. They also have reversible redox couples at high voltages, making them suitable as redox shuttles to prevent overcharging in lithium-ion batteries. The isatin derivatives can replace traditional active materials like vanadium in flow batteries and improve energy density.

Source

A polyacrylic acid grafted flow battery system using water-soluble redox-active polymers as the active materials for improved stability and solubility compared to traditional inorganic battery materials. The positive electrode uses a PAA-grafted TEMPO polymer with TEMPO as the redox active group, while the negative electrode uses a PAA-grafted viologen polymer with viologen as the active group. This allows using aqueous electrolytes with high concentrations of the polymer active materials. The grafted PAA groups increase solubility compared to ungrafted polymers. The system uses reservoirs, stack, separator, and current collectors for the flow battery configuration.

Source

Redox gating materials for reversibly transforming electronic states in functional thin film devices at low sub-volt gate voltages. The redox gating materials integrate reversible redox functionalities to engineer charge transport for reversible transformation between electronic states at low sub-volt gate voltages in functional field-effect thin film devices. The redox gating materials contain a mixture of transition metal salts with variable valency and/or redox agents containing redox-active functional groups, along with ionic electrolytes, to enable reversible transformation of electronic states in functional thin film devices at low sub-volt gate voltages. The redox gating materials avoid the irreversible chemical changes that occur during conventional electrostatic or ionic gating.

Source

A cell pack design for electric vehicle batteries that eliminates imbalance between cells and improves pack cycling stability, especially at high current density and low temperatures. The key is using a specific non-aqueous electrolyte solution in the cells containing a redox shuttle compound with a reversible potential near the overcharge voltage. This allows reciprocal charging/discharging between the positive and negative electrodes to consume overcharge currents and prevent individual cell imbalance. The electrolyte also contains an additive mix of acetonitrile and linear carbonate solvents with optimized ratios. This provides good solubility and impregnation of the separator for the redox shuttle. The cell pack design involves configuring modules with matched capacity ratios to avoid misalignment during assembly.

Source

A polymer composition for batteries and electrochromic devices with improved specific energy compared to conventional polythiophene-based compositions. The composition contains a polythiophene polycation and a polymer anion with ortho-quinone fragments that can undergo reversible oxidation and reduction. The ortho-quinone groups increase the specific energy of the composition compared to traditional polythiophene-based materials.

Source

Water-soluble trypthantrin derivatives for use as electrolytes in aqueous redox flow batteries. The derivatives are sulfonic acid and amine compounds of trypthantrin, a natural compound found in plants. They have redox properties suitable for use as anolyte and catholyte materials in aqueous redox flow batteries. The compounds provide stable cycling and energy density for aqueous redox flow batteries, especially all-organic cells. The trypthantrin derivatives can be synthesized via chlorosulfonic acid reaction for sulfonic acid derivatives, or condensation for amine derivatives.

Source