A secondary battery includes: a case having a hexahedral shape with opposite ends in a longitudinal direction being open; an electrode assembly accommodated in the case and including a negative electrode tab at one end thereof in the longitudinal direction and a positive electrode tab at an opposite end thereof in the longitudinal direction; a pair of cap assemblies respectively electrically connected to the negative electrode tab and the positive electrode tab and respectively coupled to the open opposite ends of the case; and a retainer between the electrode assembly and the case and on a side surface area of the electrode assembly at where the negative electrode tab and the positive electrode tab are not formed.

The present disclosure relates to an electrode stack for a lithium secondary battery, in which one or more positive electrodes and one or more negative electrodes are alternatingly stacked with a separator therebetween and insulation layers are formed on the outermost positive electrodes of the electrode stack. The insulation layers have an average thickness of 1 m to 8 m. The positive electrodes include a positive electrode collector; a positive electrode active material layer; and a protective layer including an inorganic compound. The protective layer is disposed between the positive electrode collector and the positive electrode active material layer. Additionally, an electrode assembly and a lithium secondary battery which include the electrode stack are also disclosed.

The present disclosure relates to an electrode stack for a lithium secondary battery, in which one or more positive electrodes and one or more negative electrodes are alternatingly stacked with a separator therebetween and insulation layers are formed on the outermost positive electrodes of the electrode stack. The insulation layers have an average thickness of 1 m to 8 m. The positive electrodes include a positive electrode collector; a positive electrode active material layer; and a protective layer including an inorganic compound. The protective layer is disposed between the positive electrode collector and the positive electrode active material layer. Additionally, an electrode assembly and a lithium secondary battery which include the electrode stack are also disclosed.

A separator for an electrochemical device, including: a porous polymer substrate having a plurality of pores; and a porous coating layer on at least one surface of the porous polymer substrate, wherein the porous coating layer comprises boehmite particles and a binder polymer, wherein the binder polymer is positioned on at least a part of the surface of the boehmite particles and connects and fixes the boehmite particles with one another. The boehmite particles have an average particle diameter of 2.0 ?m to 3.5 ?m and a specific surface area of 4.0 m.sup.2/g to 4.5 m.sup.2/g, and one side of the porous coating layer has a thickness of 2 ?m to 10 ?m.

A tab limiting sheet, a top cover assembly, and a battery are provided. The battery is insulated and disposed between a cell body and two tab bodies. The tab limiting sheet includes a first mounting part, a connecting assembly, and a second mounting part. The connecting assembly includes an elastic element and a first support element. Both ends of the elastic element are respectively connected with the first mounting part and the second mounting part. The first support element includes a first supporting part connected with the first mounting part and a second part connected with the second mounting part. When the elastic element is in a natural state, the first supporting part and the second supporting part are spaced in the first direction. When the elastic element is squeezed to a maximum deformation state, the first supporting part is tightly abutted against the second supporting part.

The present invention relates to a secondary battery including: a can having an opening in which an electrode assembly and an electrolyte are accommodated; a cap assembly mounted on the opening of the can; and a safety assembly disposed between the electrode assembly and the cap assembly and including a first fire extinguishing member that is configured to be scattered into the electrolyte when the electrode assembly experiences an increase in temperature to suppress the increase in temperature of the electrode assembly.

An electrode assembly, a secondary battery, a battery pack, and an electrical apparatus. In the electrode assembly, there are several electrode plate portions sequentially arranged in a laminated manner along its own thickness direction. During structural design, the current collector in at least one of the electrode plate portions is configured as a barrier, and by controlling the ratio between the thermal conductivity ?0 of the barrier and the thickness d0 of the barrier to be less than 3?10.sup.7 W/(K*m.sup.2), the heat flux density of the barrier along the thickness direction of the electrode assembly is reduced and the thermal resistance is increased, thus forming an effective thermal barrier in the thickness direction of the electrode assembly.

An electrode assembly, a secondary battery, a battery pack, and an electrical apparatus. In the electrode assembly, there are several electrode plate portions sequentially arranged in a laminated manner along its own thickness direction. During structural design, the current collector in at least one of the electrode plate portions is configured as a barrier, and by controlling the ratio between the thermal conductivity ?0 of the barrier and the thickness d0 of the barrier to be less than 3?10.sup.7 W/(K*m.sup.2), the heat flux density of the barrier along the thickness direction of the electrode assembly is reduced and the thermal resistance is increased, thus forming an effective thermal barrier in the thickness direction of the electrode assembly.

A tab limiting sheet, a top cover assembly, and a battery are provided. The battery is insulated and disposed between a cell body and two tab bodies. The tab limiting sheet includes a first mounting part, a connecting assembly, and a second mounting part. The connecting assembly includes an elastic element and a first support element. Both ends of the elastic element are respectively connected with the first mounting part and the second mounting part. The first support element includes a first supporting part connected with the first mounting part and a second part connected with the second mounting part. When the elastic element is in a natural state, the first supporting part and the second supporting part are spaced in the first direction. When the elastic element is squeezed to a maximum deformation state, the first supporting part is tightly abutted against the second supporting part.

An electrochemical device and an electronic device containing the electrochemical device. With a first accommodation portion disposed in the electrochemical device, a specific accommodation space is provided for a bend portion of a first tab, thereby avoiding a need to additionally increasing space for accommodating the bend portion, where the space is originally intended for accommodating the electrode assembly. This effectively saves the space occupied by the tab in the packaging shell, reduces the size of the electrochemical device, and improves an energy density of the electrochemical device. The electronic device also achieves a high energy density.