A separator for a lithium-based battery, and method for fabricating the same is disclosed. The method includes oxidizing cellulose fibrils to form oxidized cellulose having carboxylic functional groups, decorating the oxidized cellulose with nanoparticles, and forming the nanoparticle-decorated oxidized cellulose into a film to become the separator for the lithium-based battery. The cellulose may be a bacterial cellulose. The cellulose fibrils may be oxidized through a TEMPO oxidation. Decorating the oxidized cellulose with nanoparticles may include introducing a precursor solution to the oxidized cellulose that reacts with hydroxyl groups of the oxidized cellulose while preserving the carboxylic functional groups, causing the nanoparticles to nucleate on the surface of the oxidized cellulose. The nanoparticles may be composed of an oxide material. The oxide material may be SiO.sub.2. The precursor solution may be tetraethyl orthosilicate (TEOS).

A separator which includes: a porous polymer substrate having a plurality of pores; a separator base including a porous coating layer formed on at least one surface of the porous polymer substrate; and an adhesive layer formed on at least one surface of the separator base, said adhesive layer comprising a plurality of second inorganic particles and adhesive resin particles, wherein the weight ratio of the second inorganic particles to the adhesive resin particles is 5:95-60:40, and the diameter of the adhesive resin particles is 1.1-3.5 times the diameter of the second inorganic particles. An electrochemical device including the separator is also disclosed. The separator shows improved adhesion between an electrode and the separator, maintains the pores of the adhesive layer even after a process of electrode lamination, and improves the resistance of an electrochemical device.

A separator which includes: a porous polymer substrate having a plurality of pores; a separator base including a porous coating layer formed on at least one surface of the porous polymer substrate; and an adhesive layer formed on at least one surface of the separator base, said adhesive layer comprising a plurality of second inorganic particles and adhesive resin particles, wherein the weight ratio of the second inorganic particles to the adhesive resin particles is 5:95-60:40, and the diameter of the adhesive resin particles is 1.1-3.5 times the diameter of the second inorganic particles. An electrochemical device including the separator is also disclosed. The separator shows improved adhesion between an electrode and the separator, maintains the pores of the adhesive layer even after a process of electrode lamination, and improves the resistance of an electrochemical device.

Representative embodiments provide a liquid or gel separator utilized to separate and space apart first and second conductors or electrodes of an energy storage device, such as a battery or a supercapacitor. A representative liquid or gel separator comprises a plurality of particles, typically having a size (in any dimension) between about 0.5 to about 50 microns; a first, ionic liquid electrolyte; and a polymer. In another representative embodiment, the plurality of particles comprise diatoms, diatomaceous frustules, and/or diatomaceous fragments or remains. Another representative embodiment further comprises a second electrolyte different from the first electrolyte; the plurality of particles are comprised of silicate glass; the first and second electrolytes comprise zinc tetrafluoroborate salt in 1-ethyl-3-methylimidalzolium tetrafluoroborate ionic liquid; and the polymer comprises polyvinyl alcohol (“PVA”) or polyvinylidene fluoride (“PVFD”). Additional components, such as additional electrolytes and solvents, may also be included.

Representative embodiments provide a liquid or gel separator utilized to separate and space apart first and second conductors or electrodes of an energy storage device, such as a battery or a supercapacitor. A representative liquid or gel separator comprises a plurality of particles, typically having a size (in any dimension) between about 0.5 to about 50 microns; a first, ionic liquid electrolyte; and a polymer. In another representative embodiment, the plurality of particles comprise diatoms, diatomaceous frustules, and/or diatomaceous fragments or remains. Another representative embodiment further comprises a second electrolyte different from the first electrolyte; the plurality of particles are comprised of silicate glass; the first and second electrolytes comprise zinc tetrafluoroborate salt in 1-ethyl-3-methylimidalzolium tetrafluoroborate ionic liquid; and the polymer comprises polyvinyl alcohol (“PVA”) or polyvinylidene fluoride (“PVFD”). Additional components, such as additional electrolytes and solvents, may also be included.

The present invention provides compositions including polyelectrolyte complexes. The composition includes: 1) an inorganic salt comprising a metal ion having a charge of at least +1 and an anion having a charge of at least −1; and 2) a complex comprising a first species and a second species, wherein the first species is a positively charged polymerizable monomer or a first charged polymer comprising one or more positively charged monomer repeat units; the second species is a negatively charged polymerizable monomer or a second charged polymer comprising one or more negatively charged monomer repeat units; and the complex has a net charge of near zero. These compositions are useful for ion selective applications in electrochemical devices.

A separator for a non-aqueous secondary battery contains: a porous substrate and a heat-resistant porous layer that is provided on one side or on both sides of the porous substrate, and that contains a resin and inorganic particles, in which (A) the resin contains a copolymer having a vinylidene fluoride unit and a hexafluoropropylene unit satisfying particular requirements, a content of the inorganic particles in the heat-resistant porous layer is from 50% by mass to 90% by mass, and the inorganic particles contain first inorganic particles and second inorganic particles satisfying particular size requirements, or (B) a content of the inorganic particles in the heat-resistant porous layer is from 50% by mass to 90% by mass, and the inorganic particles contain first inorganic particles that are metal sulfate (or metal hydroxide) particles and second inorganic particles that are inorganic particles other than metal sulfate (or metal hydroxide) particles.

A separator for a non-aqueous secondary battery contains: a porous substrate and a heat-resistant porous layer that is provided on one side or on both sides of the porous substrate, and that contains a resin and inorganic particles, in which (A) the resin contains a copolymer having a vinylidene fluoride unit and a hexafluoropropylene unit satisfying particular requirements, a content of the inorganic particles in the heat-resistant porous layer is from 50% by mass to 90% by mass, and the inorganic particles contain first inorganic particles and second inorganic particles satisfying particular size requirements, or (B) a content of the inorganic particles in the heat-resistant porous layer is from 50% by mass to 90% by mass, and the inorganic particles contain first inorganic particles that are metal sulfate (or metal hydroxide) particles and second inorganic particles that are inorganic particles other than metal sulfate (or metal hydroxide) particles.

A separator for a lithium secondary battery and a method for manufacturing the same. The separator for a lithium secondary battery includes: a porous polymer substrate; and a porous coating layer on at least one surface of the porous polymer substrate. The porous coating layer includes inorganic particles, a fluorine-containing binder polymer (A), and an ethylenic copolymer (B) having an ethylene monomer-derived repeating unit (a) and a vinyl acetate monomer-derived repeating unit (b). It is possible to provide a separator having improved adhesion peel strength between the porous coating layer and the porous polymer substrate and improved adhesion Lami strength to an electrode at the same time and a method for manufacturing the same by using an ethylenic copolymer having predetermined characteristics.

A separator for a lithium secondary battery and a method for manufacturing the same. The separator for a lithium secondary battery includes: a porous polymer substrate; and a porous coating layer on at least one surface of the porous polymer substrate. The porous coating layer includes inorganic particles, a fluorine-containing binder polymer (A), and an ethylenic copolymer (B) having an ethylene monomer-derived repeating unit (a) and a vinyl acetate monomer-derived repeating unit (b). It is possible to provide a separator having improved adhesion peel strength between the porous coating layer and the porous polymer substrate and improved adhesion Lami strength to an electrode at the same time and a method for manufacturing the same by using an ethylenic copolymer having predetermined characteristics.