Abstract:
An energy storage device comprising: an anode; and a solute-containing electrolyte composition wherein the solute concentration in the electrolyte composition is sufficiently high to form a regenerative solid electrolyte interface layer on a surface of the anode only during charging of the energy storage device, wherein the regenerative layer comprises at least one solute or solvated solute from the electrolyte composition.
Abstract:
RFBs having solid hybrid electrodes can address at least the problems of active material consumption, electrode passivation, and metal electrode dendrite growth that can be characteristic of traditional batteries, especially those operating at high current densities. The RFBs each have a first half cell containing a first redox couple dissolved in a solution or contained in a suspension. The solution or suspension can flow from a reservoir to the first half cell. A second half cell contains the solid hybrid electrode, which has a first electrode connected to a second electrode, thereby resulting in an equipotential between the first and second electrodes. The first and second half cells are separated by a separator or membrane.
Abstract:
Nanostructured bismuth materials can be utilized as an insertion material in electrodes for magnesium energy storage devices to take advantage of short diffusion lengths for Mg 2+ . The result can be a significantly increased charge/discharge rates and/or improved cycling stabilities. In one example, an energy storage device has magnesium as an electroactive species, an electrolyte salt containing magnesium, and an anode having bismuth nanostructures. The bismuth nanostructures have at least one dimension that is less than or equal to 25 nm. At least a portion of the magnesium is reversibly inserted into, and extracted from, the anode during discharging and charging states, respectively.
Abstract:
Electrolytes for Mg-based energy storage devices can be formed from non-nucleophilic Mg 2+ sources to provide outstanding electrochemical performance and improved electrophilic susceptibility compared to electrolytes employing nucleophilic sources. The instant electrolytes are characterized by high oxidation stability (up to 3.4 V vs Mg), improved electrophile compatibility and electrochemical reversibility (up to 100% coulombic efficiency). Synthesis of the Mg 2+ electrolytes utilizes inexpensive and safe magnesium dihalides as non-nucleophilic Mg 2+ sources in combination with Lewis acids, MR a X 3-a (for 3≥ a≥ 1). Furthermore, addition of free-halide-anion donors can improve the coulombic efficiency of Mg electrolytes from nucleophilic or non-nucleophilic Mg 2+ sources.
Abstract:
The performance of sodium-based energy storage devices can be improved according to methods and devices based on surface-driven reactions between sodium ions and functional groups attached to surfaces of the cathode. The cathode substrate, which includes a conductive material, can provide high electron conductivity while the surface functional groups can provide reaction sites to store sodium ions. During discharge cycles, sodium ions will bind to the surface functional groups. During charge cycles, the sodium ions will be released from the surface functional groups. The surface-driven reactions are preferred compared to intercalation reactions.
Abstract:
Improved lithium-sulfur energy storage systems can utilizes LixSy as a component in an electrode of the system. For example, the energy storage system can include a first electrode current collector, a second electrode current collector, and an ion-permeable separator separating the first and second electrode current collectors. A second electrode is arranged between the second electrode current collector and the separator. A first electrode is arranged between the first electrode current collector and the separator and comprises a first condensed-phase fluid comprising LixSy. The energy storage system can be arranged such that the first electrode functions as a positive or a negative electrode.
Abstract:
A crystalline nanowire and method of making a crystalline nanowire are disclosed. The method includes dissolving a first nitrate salt and a second nitrate salt in an acrylic acid aqueous solution. An initiator is added to the solution, which is then heated to form polyacrylatyes. The polyacrylates are dried and calcined. The nanowires show high reversible capacity, enhanced cycleability, and promising rate capability for a battery or capacitor.
Abstract:
Some batteries can exhibit greatly improved performance by utilizing electrodes having randomly arranged graphene nanosheets forming a network of channels defining continuous flow paths through the electrode. The network of channels can provide a diffusion pathway for the liquid electrolyte and/or for reactant gases. Metal-air batteries can benefit from such electrodes. In particular Li-air batteries show extremely high capacities, wherein the network of channels allow oxygen to diffuse through the electrode and mesopores in the electrode can store discharge products.
Abstract:
Rechargeable lithium-sulfur batteries having a cathode that includes a graphene-sulfur nanocomposite can exhibit improved characteristics. The graphene-sulfur nanocomposite can be characterized by graphene sheets with particles of sulfur adsorbed to the graphene sheets. The sulfur particles have an average diameter less than 50 nm.
Abstract:
A method of producing an array of oriented nanofibers that involves forming a solution that includes at least one electroactive species. An electrode substrate is brought into contact with the solution. A current density is applied to the electrode substrate that includes at least a first step of applying a first substantially constant current density for a first time period and a second step of applying a second substantially constant current density for a second time period. The first and second time periods are of sufficient duration to electrically deposit on the electrode substrate an array of oriented nanofibers produced from the electroactive species. Also disclosed are films that include arrays or networks of oriented nanofibers and a method for amperometrically detecting or measuring at least one analyte in a sample.