An electrochemical cell that cycles lithium ions is provided. The electrochemical cell includes a first electrode, a second electrode, and an electrolyte layer disposed between the first electrode and the second electrode. The first electrode includes a first plurality of solid-state electroactive material particles and a first polymeric gel electrolyte, where the first polymeric gel electrolyte includes a first additive. The second electrode includes a second plurality of solid-state electroactive material particles and a second polymeric gel electrolyte that is different from the first polymeric gel electrolyte, where the second polymeric gel electrolyte includes a second additive. The electrolyte layers include a third polymeric gel electrolyte that is different from both the first polymeric gel electrolyte and the second polymeric gel electrolyte.

An electrochemical cell that cycles lithium ions is provided. The electrochemical cell includes a first electrode, a second electrode, and an electrolyte layer disposed between the first electrode and the second electrode. The first electrode includes a first plurality of solid-state electroactive material particles and a first polymeric gel electrolyte, where the first polymeric gel electrolyte includes a first additive. The second electrode includes a second plurality of solid-state electroactive material particles and a second polymeric gel electrolyte that is different from the first polymeric gel electrolyte, where the second polymeric gel electrolyte includes a second additive. The electrolyte layers include a third polymeric gel electrolyte that is different from both the first polymeric gel electrolyte and the second polymeric gel electrolyte.

A solid polymer electrolyte having a reinforcing substrate, a polymer having ethylene oxide portions and hydrocarbon portions with pendent functional groups having high relative permittivity for an electrochemical cell is provided. The solid polymer electrolyte may provide good ionic conductivity at room temperature and good mechanical strength.

A solid polymer electrolyte having a reinforcing substrate, a polymer having ethylene oxide portions and hydrocarbon portions with pendent functional groups having high relative permittivity for an electrochemical cell is provided. The solid polymer electrolyte may provide good ionic conductivity at room temperature and good mechanical strength.

Set forth herein are pellets, thin films, and monoliths of lithium-stuffed garnet electrolytes having engineered surfaces. These engineered surfaces have a list of advantageous properties including, but not limited to, low surface area resistance, high Li.sup.+ ion conductivity, low tendency for lithium dendrites to form within or thereupon when the electrolytes are used in an electrochemical cell. Other advantages include voltage stability and long cycle life when used in electrochemical cells as a separator or a membrane between the positive and negative electrodes. Also set forth herein are methods of making these electrolytes including, but not limited to, methods of annealing these electrolytes under controlled atmosphere conditions. Set forth herein, additionally, are methods of using these electrolytes in electrochemical cells and devices. The instant disclosure further includes electrochemical cells which incorporate the lithium-stuffed garnet electrolytes set forth herein.

Set forth herein are pellets, thin films, and monoliths of lithium-stuffed garnet electrolytes having engineered surfaces. These engineered surfaces have a list of advantageous properties including, but not limited to, low surface area resistance, high Li.sup.+ ion conductivity, low tendency for lithium dendrites to form within or thereupon when the electrolytes are used in an electrochemical cell. Other advantages include voltage stability and long cycle life when used in electrochemical cells as a separator or a membrane between the positive and negative electrodes. Also set forth herein are methods of making these electrolytes including, but not limited to, methods of annealing these electrolytes under controlled atmosphere conditions. Set forth herein, additionally, are methods of using these electrolytes in electrochemical cells and devices. The instant disclosure further includes electrochemical cells which incorporate the lithium-stuffed garnet electrolytes set forth herein.

The present invention provides a composition for a gel polymer electrolyte, the composition including: an oligomer represented by Formula 1; an additive; a polymerization initiator; a lithium salt; and a non-aqueous solvent, the additive including at least one compound selected from the group consisting of a substituted or unsubstituted phosphate-based compound and a substituted or unsubstituted benzene-based compound, a gel polymer electrolyte prepared using the same, and a lithium secondary battery.

The present invention provides a composition for a gel polymer electrolyte, the composition including: an oligomer represented by Formula 1; an additive; a polymerization initiator; a lithium salt; and a non-aqueous solvent, the additive including at least one compound selected from the group consisting of a substituted or unsubstituted phosphate-based compound and a substituted or unsubstituted benzene-based compound, a gel polymer electrolyte prepared using the same, and a lithium secondary battery.

One of the objects of the present invention is to suppress a short circuit due to metal deposition in an insulating layer in a secondary battery in which a positive electrode and a negative electrode are disposed to face each other via the insulating layer. The secondary battery comprises a battery element including at least one positive electrode 11 and at least one negative electrode 12, and a casing that seals the battery element together with an electrolyte. At least one of the positive electrode 11 and the negative electrode 12 comprises a current collector, an active material layer formed on at least one surface of the current collector, and an insulating layer 112 formed on the surface of the active material layer. The electrolyte comprises an electrolyte component and a crosslinked gelling agent. The gelling agent exists at least between the active material layer of the positive electrode 11 and the active material layer of the negative electrode 12, and the ratio Rg of the gelling agent to 100% by mass of the electrolyte component in between the active material layer of the positive electrode 11 and the active material layer of the negative electrode 12 is 0<Rg≤5% by mass.

One of the objects of the present invention is to suppress a short circuit due to metal deposition in an insulating layer in a secondary battery in which a positive electrode and a negative electrode are disposed to face each other via the insulating layer. The secondary battery comprises a battery element including at least one positive electrode 11 and at least one negative electrode 12, and a casing that seals the battery element together with an electrolyte. At least one of the positive electrode 11 and the negative electrode 12 comprises a current collector, an active material layer formed on at least one surface of the current collector, and an insulating layer 112 formed on the surface of the active material layer. The electrolyte comprises an electrolyte component and a crosslinked gelling agent. The gelling agent exists at least between the active material layer of the positive electrode 11 and the active material layer of the negative electrode 12, and the ratio Rg of the gelling agent to 100% by mass of the electrolyte component in between the active material layer of the positive electrode 11 and the active material layer of the negative electrode 12 is 0<Rg≤5% by mass.