Disclosed is a hybrid electrochemical cell with a first conductor having at least one portion that is both a first capacitor electrode and a first battery electrode. The hybrid electrochemical cell further includes a second conductor having at least one portion that is a second capacitor electrode and at least one other portion that is a second battery electrode. An electrolyte is in contact with both the first conductor and the second conductor. In some embodiments, the hybrid electrochemical cell further includes a separator between the first conductor and the second conductor to prevent physical contact between the first conductor and the second conductor, while facilitating ion transport between the first conductor and the second conductor.

Disclosed is a hybrid electrochemical cell with a first conductor having at least one portion that is both a first capacitor electrode and a first battery electrode. The hybrid electrochemical cell further includes a second conductor having at least one portion that is a second capacitor electrode and at least one other portion that is a second battery electrode. An electrolyte is in contact with both the first conductor and the second conductor. In some embodiments, the hybrid electrochemical cell further includes a separator between the first conductor and the second conductor to prevent physical contact between the first conductor and the second conductor, while facilitating ion transport between the first conductor and the second conductor.

Photocurable compositions that combine redox-active semiconducting organic polymers with photocurable organic molecules are provided. Upon exposure to radiation, the photocurable compositions form ion-permeable, electrically conductive crosslinked organic films that can be used as conducting channels in n-channel or p-channel organic electrochemical transistors, including vertical organic electrochemical transistors (vOECTs). The vOECTs can be incorporated in complementary electronic circuits.

A hybrid supercapacitor where the charging state is indicated by color is demonstrated. The device comprises a molecular network that functions as both the battery-type electrode and the charge indicator. Related batteries, electrodes and devices, their processes of preparation and methods of use are provided as well. Further included in this invention are data-storage devices and catalysts based on multilayers comprising metal-ion organic complexes. This invention further provides methods of preparation of the multilayers, of the data-storage devices, of the catalyst devices and methods of use thereof.

A flexible energy storage device with a redox-active polymer hydrogel electrolyte is provided. The flexible energy storage device can include a pair of electrodes separated by the redox-active polymer hydrogel electrolyte. The redox-active polymer hydrogel electrolyte can include a polymer hydrogel, charge balancing anions and redox-active transition metal cations at least one selected from the group consisting of vanadium, chromium, manganese, cobalt, and copper. The flexible energy storage device may retain greater than 75% of an unbent specific capacitance when bent at an angle of 100 to 170°.

Described are energy storage devices employing a gas storage structure, which can accommodate or store gas evolved from the energy storage device. The energy storage device comprises an electrochemical cell with electrodes comprising metal-containing compositions, like metal oxides, metal nitrides, or metal hydrides, and a solid state electrolyte.

A lamellar transition metal sulfide composition having layers of an amorphous transition metal sulfide with cations interspersed between the layers is described. Also described are methods of synthesizing the lamellar transition metal sulfides and the use of the lamellar transition metal sulfides in electrodes, e.g., in metal-ion batteries, metal-ion/sulfur batteries, and capacitors.

The disclosure provides a chemical reduction of a metal in a cable of an electrical network, which brings about an improvement in the conductive properties of said metal and a reduction in losses during electric power transmission. The invention discloses a reducing compound with a high concentration of quasi-free electrons, which is obtained as a result of the solvation of metals selected from group I and group II of the main group of the periodic table of elements and of amines selected from the group consisting of: pyridine, and dimethylformamide dispersed in a liquid oligomer, with a metal:amine:dielectric molar ratio of 1:2:1.5, allowing, in an alternating electromagnetic field, to initiate a pulsed injection of electrons into the network with a periodicity equal to frequency of alternation of the voltage.

Formation process for a potassium-ion hybrid supercapacitor, the process comprising: a) supplying the potassium-ion hybrid supercapacitor comprising: a negative electrode comprising graphite, a positive electrode comprising activated carbon, an electrolyte comprising a potassium salt, b) charging the supercapacitor at constant current in a protocol of between C.sub.x/50 and C.sub.x/2, to a charge cutoff voltage of between 3.0 V and 3.3 V, c) holding the supercapacitor at the charge cutoff voltage until the leakage current is between C.sub.x/2000 and C.sub.x/500, d) discharging the supercapacitor at constant current in a protocol of between C.sub.x/50 and C.sub.x, to a discharge cutoff voltage of between 0 V and 2 V,
where the process further comprises degassing the supercapacitor after one of steps b) to d).

The disclosed technology generally relates to energy storage devices, and more particularly to energy storage devices comprising frustules. According to an aspect, a supercapacitor comprises a pair of electrodes and an electrolyte, wherein at least one of the electrodes comprises a plurality of frustules having formed thereon a surface active material. The surface active material can include nanostructures. The surface active material can include one or more of a zinc oxide, a manganese oxide and a carbon nanotube.