This separator for a nonaqueous electrolyte secondary battery comprises a porous substrate, a heat-resistant layer that is formed on the porous substrate, and clusters of filler particles that are present in dot shapes on the surface of the heat-resistant layer. The filler particles are particles of a compound including at least one of phosphorus, silicon, boron, nitrogen, potassium, sodium, and bromine, and the transformation point at which the filler particles transform from a solid phase to a liquid phase or thermally decompose is in the range 180° C.-1000° C. This separator electrode for a nonaqueous electrolyte secondary battery can suppress heat production of the battery during a nail puncture test, while also suppressing an increase in battery resistance.

The present invention provides an oxide-based solid-state secondary battery which may be enlarged at a low cost and for which production costs are reduced. A binder for a solid-state secondary battery using an oxide-based solid-state electrolyte, wherein the binder contains a vinylidene fluoride unit and a fluorinated monomer unit excluding the vinylidene fluoride unit.

Provided is a lithium secondary battery comprising: a positive electrode including a positive electrode active material; a negative electrode including a negative electrode active material; and a first functional layer between the positive electrode and the negative electrode, wherein the first functional layer includes plate-like polyolefin particles having an average diameter of 1 μm to 8 μm, and the positive electrode includes a positive electrode active material layer including a positive electrode active material and a flame retardant, or has a stacked structure including a positive electrode active material layer and a second functional layer including a flame retardant.

The present application provides an organic-inorganic hybrid complex which can be used in a coating of a separator for a secondary battery, wherein the organic-inorganic hybrid complex is formed from basic units represented by formula (I) being periodically assembled in at least one spatial direction: [L.sub.x-i□i][M.sub.aC.sub.b].A.sub.z (I), wherein a defect percentage expressed in i/x*100% is 1% to 30%. The present application further provides a coating composition comprising the organic-inorganic hybrid complex, a coating formed from the coating composition, a separator comprising the coating for a secondary battery, a secondary battery comprising the separator, a battery module, a battery pack and a device. By applying the organic-inorganic hybrid complex of the present application in a coating, the electrolyte infiltration of a separator for a secondary battery is improved while increasing the electrolyte retention rate, thereby improving the rate capability and cycling life of the secondary battery.

An electrochemical device includes electrode plates and a separation layer formed on a surface of an electrode plate. The separation layer includes a porous layer formed on the surface of the electrode plate. The porous layer includes nanofibers. It takes 15 seconds or less for an electrolytic solution to infiltrate into the separation layer. The separation layer exhibits functions of a separator. Therefore, the electrochemical device achieves at least a relatively high energy density without using a stand-alone separator.

An electrochemical device includes electrode plates and a separation layer formed on a surface of an electrode plate. The separation layer includes a porous layer formed on the surface of the electrode plate. The porous layer includes nanofibers. It takes 15 seconds or less for an electrolytic solution to infiltrate into the separation layer. The separation layer exhibits functions of a separator. Therefore, the electrochemical device achieves at least a relatively high energy density without using a stand-alone separator.

An electrochemical device includes an electrode plate and a separation layer on at least one surface of the electrode plate. The separation layer includes a nanofibrous porous substrate including nanofibers and polymer particles distributed in the nanofibrous porous substrate including nanofibers. A melting temperature of the polymer particles is 70° C. to 150° C.

There is provided an LDH separator including a porous substrate and a layered double hydroxide (LDH)-like compound that fills up pores of the porous substrate. The LDH-like compound is a hydroxide and/or an oxide with a layered crystal structure, containing (i) Ti, Y, and optionally Al and/or Mg, and (ii) at least one additive element M selected from the group consisting of In, Bi, Ca, Sr, and Ba.

A method for enhancing battery cycle performance. The method is applied in a battery and includes: charging, at a first stage, the battery at a first-stage current until reaching a first-stage voltage; and charging, at a second stage, the battery at a second-stage current until reaching a second-stage voltage. The second-stage voltage is greater than the first-stage voltage, and the second-stage current is less than the first-stage current. The battery includes an electrolytic solution containing an organic solvent. The organic solvent includes a chain carboxylate compound. A weight percent of the chain carboxylate compound in the organic solvent is 10% to 70%. This application further provides an electronic device. The method can enhance high-temperature cycle and storage performance of the battery.

Provided are a separator for a lithium secondary battery including a substrate and a heat-resistance porous layer disposed on at least one surface of the substrate and including a cross-linked binder, wherein the cross-linked binder has a cross-linking structure of a compound represented by Chemical Formula 2, and a lithium secondary battery including the same.