A separator for a bobbin-style electrochemical cell is inserted into an interior opening within a ring-shaped cathode in an electrochemical cell can. An expansion force is then applied to an interior surface of the separator to press the separator against the interior walls of the cathode. A tool may then remove various creases and/or wrinkles in the separator and/or may then heat seal at least a portion of the tubular walls of the separator to minimize the void space between the separator and active material (e.g., cathode and/or anode) within the electrochemical cell.

The present disclosure relates to a sodium-ion storage material and an electrode material for a sodium-ion battery, an electrode material for a seawater battery, an electrode for a sodium-ion battery, an electrode for a seawater battery, a sodium-ion battery, and a seawater battery, which include the sodium-ion storage material. Specifically, the sodium-ion storage material may include one or more materials selected from the group consisting of Cu.sub.xS, FeS, FeS.sub.2, Ni.sub.3S, NbS.sub.2, SbO.sub.x, SbS.sub.x, SnS and SnS.sub.2, wherein 0<x2. When the sodium-ion storage material according to the present disclosure is used, it may exhibit high discharge capacity, and when the sodium-ion storage material is applied to a sodium-ion battery which is a secondary battery, it may exhibit excellent charge/discharge cycle characteristics.

Provided is a metal-air battery which is improved in battery performance such as stability in charge/discharge cycle characteristics by suppressing the generation of byproducts not only on the metal anode but also on the air cathode. A metal-air battery of the present invention includes an anode 1, an air cathode 3 and an electrolyte 2 that is interposed between the anode 1 and the air cathode 3, wherein the anode 1 contains aluminum, the electrolyte 2 contains an ionic liquid or a non-aqueous electrolyte solution, and the air cathode 3 contains a non-oxide ceramic.

An electrochemical energy-storage cell comprises a flexible positive electrode and a flexible negative electrode including a gallium-based liquid metal dispersed on a flexible wire mesh. The electrochemical energy-storage cell also comprises a membrane having one face in contact with the flexible positive electrode and an opposing face in contact with the flexible negative electrode.

Crosslinked polymers and related compositions and related compositions, electrochemical cells, batteries, methods and systems are described. The crosslinked polymers have at least one redox active monomeric moiety having a redox potential of 0.5 V to 3.0 V with reference to Li/Li.sup.+ electrode potential under standard conditions or 2.54 V to 0.04 V vs. SHE and has a carbocyclic structure and at least one carbonyl group or a carboxyl group on the carbocyclic structure. The crosslinked polymers also include at least one comonomeric moiety with at least one of the at least one redox active monomeric moiety and/or the at least one comonomeric moiety has a denticity of three to six corresponding to a three to six connected network polymer, and provide stable, high capacity organic electrode materials.

Various embodiments are directed to an electrochemical cell having a non-homogeneous anode. The electrochemical cell includes a container, a cathode forming a hollow cylinder within the container, an anode positioned within the hollow cylinder of the cathode, and a separator between the cathode and the anode. The anode comprises at least two concentric anode portions, defined by different anode characteristics. For example, the two anode portions may contain different surfactant types, which provides the two anode portions with different charge transfer resistance characteristics. By lowering the charge transfer resistance of a portion of an anode located proximate the current collector of the cell (and away from the separator) relative to an anode portion located adjacent the separator, improved cell discharge performance may be obtained.

A separator for a bobbin-style electrochemical cell is inserted into an interior opening within a ring-shaped cathode in an electrochemical cell can. An expansion force is then applied to an interior surface of the separator to press the separator against the interior walls of the cathode. A tool may then remove various creases and/or wrinkles in the separator and/or may then heat seal at least a portion of the tubular walls of the separator to minimize the void space between the separator and active material (e.g., cathode and/or anode) within the electrochemical cell.

Alkaline electrochemical cells are provided, wherein a conductive carbon is included in the cell's cathode in order to decrease resistivity of the cathode, so as to improve the discharge of the cell, particularly in high drain applications. The conductive carbon may comprise carbon nanotubes and/or graphene. Methods for preparing such cells are also provided.

According to one embodiment, a secondary battery includes a positive electrode, a negative electrode, a separator, a first electrolyte and a second electrolyte. The separator is arranged at least between the positive electrode and the negative electrode. The first electrolyte is contained at least in the positive electrode. The first electrolyte includes a lithium salt and an aqueous solvent. The second electrolyte is contained at least in the negative electrode. The second electrolyte includes a bis(fluorosulfonyl)imide salt and an aqueous solvent.

A seawater battery cell may include: a seawater battery module having an anode and a cathode; a watertight structure coupled to the seawater battery module, the watertight structure being configured to tightly seal the anode and the cathode from seawater; a first watertight connector portion electrically connected to any one of the anode and the cathode; and a second watertight connector portion electrically connected to remaining one of the anode and the cathode and coupled to a first watertight connector portion of an adjacent seawater battery cell. As a result, the seawater battery cell, which can be fully submerged under seawater, can be applied to various fields.