The present disclosure provides a sheet-form electrode for a secondary battery, comprising a current collector; an electrode active material layer formed on one surface of the current collector; and a first porous supporting layer formed on the electrode active material layer. The sheet-form electrode for a secondary battery according to the present disclosure has supporting layers on at least one surface thereof to exhibit surprisingly improved flexibility and prevent the release of the electrode active material layer from a current collector even if intense external forces are applied to the electrode, thereby preventing the decrease of battery capacity and improving the cycle life characteristic of the battery.

The present disclosure provides a sheet-form electrode for a secondary battery, comprising a current collector; an electrode active material layer formed on one surface of the current collector; and a first porous supporting layer formed on the electrode active material layer. The sheet-form electrode for a secondary battery according to the present disclosure has supporting layers on at least one surface thereof to exhibit surprisingly improved flexibility and prevent the release of the electrode active material layer from a current collector even if intense external forces are applied to the electrode, thereby preventing the decrease of battery capacity and improving the cycle life characteristic of the battery.

The lithium secondary battery of the present invention satisfies at least one requirement selected from the group consisting of requirements (i) and (ii). (i) An electrolyte liquid includes an anode mediator which is dissolved along with lithium in a solvent of the electrolyte liquid to give, to the electrolyte liquid, an equilibrium potential which is not more than an upper limit potential at which a compound of lithium and an anode active material is formed, and does not include a compound which is dissolved along with lithium in the solvent of the electrolyte liquid to give, to the electrolyte liquid, an equilibrium potential which is more than the upper limit potential. (ii) The electrolyte liquid only includes, as the anode mediator, only a compound which is dissolved along with lithium in the solvent of the electrolyte liquid to give, to the electrolyte liquid, the equilibrium potential which is not more than the upper limit potential at which the compound of lithium and the anode active material is formed.

The present disclosure provides an energy storage device comprising at least one electrochemical cell comprising a negative current collector, a negative electrode in electrical communication with the negative current collector, an electrolyte in electrical communication with the negative electrode, a positive electrode in electrical communication with the electrolyte and a positive current collector in electrical communication with the positive electrode. The negative electrode comprises an alkali metal. Upon discharge, the electrolyte provides charged species of the alkali metal. The positive electrode can include a Group IIIA, IVA, VA and VIA of the periodic table of the elements, or a transition metal (e.g., Group 12 element).

Disclosed herein is a cable-type secondary battery having a horizontal cross section of a predetermined shape and extending longitudinally, comprising: a core for supplying lithium ions, which comprises an electrolyte; an inner electrode, comprising an open-structured inner current collector surrounding the outer surface of the core for supplying lithium ions, an inner electrode active material layer formed on the surface of the inner current collector, and a first electrolyte-absorbing layer formed on the outer surface of the inner electrode active material layer; a separation layer surrounding the outer surface of the inner electrode to prevent a short circuit between electrodes; a second electrolyte-absorbing layer formed on the surface of the separator; and an outer electrode surrounding the outer surface of the second electrolyte-absorbing layer and comprising an outer electrode active material layer and an outer current collector.

Disclosed herein is a cable-type secondary battery having a horizontal cross section of a predetermined shape and extending longitudinally, comprising: a core for supplying lithium ions, which comprises an electrolyte; an inner electrode, comprising an open-structured inner current collector surrounding the outer surface of the core for supplying lithium ions, an inner electrode active material layer formed on the surface of the inner current collector, and a first electrolyte-absorbing layer formed on the outer surface of the inner electrode active material layer; a separation layer surrounding the outer surface of the inner electrode to prevent a short circuit between electrodes; a second electrolyte-absorbing layer formed on the surface of the separator; and an outer electrode surrounding the outer surface of the second electrolyte-absorbing layer and comprising an outer electrode active material layer and an outer current collector.

The present disclosure provides an energy storage device comprising at least one electrochemical cell comprising a negative current collector, a negative electrode in electrical communication with the negative current collector, an electrolyte in electrical communication with the negative electrode, a positive electrode in electrical communication with the electrolyte and a positive current collector in electrical communication with the positive electrode. The negative electrode comprises an alkali metal. Upon discharge, the electrolyte provides charged species of the alkali metal. The positive electrode can include a Group IIIA, IVA, VA and VIA of the periodic table of the elements, or a transition metal (e.g., Group 12 element).

A lithium ion battery component includes a support selected from the group consisting of a current collector, a negative electrode, and a porous polymer separator. A lithium donor is present i) as an additive with a non-lithium active material in a negative electrode on the current collector, or ii) as a coating on at least a portion of the negative electrode, or iii) as a coating on at least a portion of the porous polymer separator. The lithium donor has a formula selected from the group consisting of Li.sub.8-yM.sub.yP.sub.4, wherein M is Fe, V, or Mn and wherein y ranges from 1 to 4; Li.sub.10-yTi.sub.yP.sub.4, wherein y ranges from 1 to 2; Li.sub.xP, wherein 0<x3; and Li.sub.2CuP.

A lithium ion battery component includes a support selected from the group consisting of a current collector, a negative electrode, and a porous polymer separator. A lithium donor is present i) as an additive with a non-lithium active material in a negative electrode on the current collector, or ii) as a coating on at least a portion of the negative electrode, or iii) as a coating on at least a portion of the porous polymer separator. The lithium donor has a formula selected from the group consisting of Li.sub.8-yM.sub.yP.sub.4, wherein M is Fe, V, or Mn and wherein y ranges from 1 to 4; Li.sub.10-yTi.sub.yP.sub.4, wherein y ranges from 1 to 2; Li.sub.xP, wherein 0<x3; and Li.sub.2CuP.

The present invention provides a nickel-zinc secondary battery, including: a battery case; an electrode assembly, disposed in the battery case; and an electrolyte solution, positioned in the battery case, and filled around the electrode assembly, wherein the electrode assembly includes a nickel positive electrode, a zinc negative electrode, and a membrane separator disposed between the nickel positive electrode and the zinc negative electrode; the nickel positive electrode includes: a substrate and positive electrode material coated on the surface of the substrate; the positive electrode material includes: 68 wt %69 wt % positive electrode active material, 0.6 wt %1 wt % yttrium oxide, 0.2 wt %0.6 wt % calcium hydroxide, 3.5 wt %4 wt % nickel powder, and a binder in balance; and the positive electrode active material is a spherical nickel hydroxide coated with Co3+. The nickel-zinc secondary battery provided by the present invention can reduce the amount of hydrogen evolved and have good cycling performance while maintaining the battery capacity. The present invention further provides a method for preparing a nickel-zinc secondary battery.