The present disclosure provides a lithium ion battery, a power battery module, a battery pack, an electric vehicle and an energy storage device. The lithium ion battery includes a casing and an electrode core packaged in the casing. The electrode core includes a positive electrode sheet, a negative electrode sheet, and a separator located between the positive electrode sheet and the negative electrode sheet. The positive electrode sheet includes a positive electrode current collector and a positive electrode material layer loaded on the positive electrode current collector. Among the positive electrode current collector, the positive electrode material layer, the negative electrode sheet, and the separator, the one with the lowest melting point is defined as an effective component. The effective component meets:

[00001]$3\le A=d_2\rho C_p\times \left(\frac{1.35L}{W}\right)\le 850.$

An electricity storage device member is provided. The electricity storage device member includes a base material mainly composed of a metal and a resin layer stacked on the base material, in which the resin layer contains a crosslinked fluororesin.

A secondary battery includes an outer package member, an electrode terminal, and a battery device. The outer package member has a flat and columnar shape and includes a first bottom part and a second bottom part opposed to each other. The electrode terminal is supported by the first bottom part and is insulated from the first bottom part. The battery device is contained inside the outer package member and includes a first electrode and a second electrode. The first bottom part has a recess around the electrode terminal.

A secondary battery includes an outer package member, a battery device, and an insulating member. The outer package member has a flat and columnar shape and includes a first bottom part and a second bottom part opposed to each other. The battery device is contained inside the outer package member, and has a first through hole extending from the first bottom part toward the second bottom part. The insulating member is adhered in part to the battery device between the second bottom part and the battery device, and has a second through hole at a position overlapping with the first through hole.

Provided is a battery module that prevents a new current path that may be formed due to molten metal resulting from a molten and cut fuse, and has better safety than conventional battery modules. A battery module includes: module terminals; a battery cell group including a plurality of battery cells; and a plurality of bus bars connecting the plurality of battery cells of this battery cell group and connecting this battery cell group with the module terminals. At least one of the plurality of bus bars has a fuse. The battery module has a space that is located below the fuse and that allows the molten fuse to fall.

A secondary battery includes: a case having an accommodating space therein; an electrode assembly accommodated in the case and having an uncoated portion on one end thereof; a current collector plate electrically connected to the uncoated portion of the electrode assembly; a cap plate sealing the case; and an electrode terminal outside the cap plate and electrically connected to the current collector plate. The current collector plate has a hole through which the electrode terminal passes and a coupling protrusion protruding toward the electrode assembly along a periphery of the hole.

The present invention provides a single electrode assembly, in which a plurality of negative electrodes and positive electrodes are stacked alternately and repeatedly, and separators are disposed between the plurality of negative electrodes and positive electrodes, the electrode assembly including: a negative electrode tab part formed on one end of the electrode assembly and extending from the plurality of negative electrodes; a positive electrode bus bar spaced apart from the negative electrode tab part on the one end of the electrode assembly and electrically connecting the plurality of the positive electrodes; a positive electrode tab part formed on the other end of the electrode assembly opposite to the one end and extending from the plurality of positive electrodes; and a negative electrode bus bar spaced apart from the positive electrode tab part on the other end of the electrode assembly and electrically connecting the plurality of the negative electrodes.

The present invention provides a single electrode assembly, in which a plurality of negative electrodes and positive electrodes are stacked alternately and repeatedly, and separators are disposed between the plurality of negative electrodes and positive electrodes, the electrode assembly including: a negative electrode tab part formed on one end of the electrode assembly and extending from the plurality of negative electrodes; a positive electrode bus bar spaced apart from the negative electrode tab part on the one end of the electrode assembly and electrically connecting the plurality of the positive electrodes; a positive electrode tab part formed on the other end of the electrode assembly opposite to the one end and extending from the plurality of positive electrodes; and a negative electrode bus bar spaced apart from the positive electrode tab part on the other end of the electrode assembly and electrically connecting the plurality of the negative electrodes.

A secondary battery includes a bare cell including an electrode assembly, an electrode tab drawn upwardly from the electrode assembly, and a pouch surrounding the electrode assembly, the electrode tab being exposed to an outside through the pouch, a protection circuit module (PCM) connected to the electrode tab, a case holder disposed between the pouch and the PCM to support the PCM, a case top on the bare cell, the PCM and the case holder being covered by the case top, a case bottom at a bottom side of the bare cell, and a plate attached to a side surface of the bare cell, the plate being coupled to the case top and the case bottom.

A battery module including: a battery cell having opposite top and bottom surfaces, a long side surface extending between the top surface and the bottom surface, and a shot side surface extending between the top surface, the bottom surface, and the long side surface, the battery cell including a terminal on the top surface; an end plate having an end area in contact with the long side surface of the battery cell and an end flange bent from a lower end of the end area in a direction away from the long side surface; and a side plate having a side area in contact with the short side surface of the battery cell, a side flange bent from a lower end of the side area to cover the bottom surface of the battery cell, and a side binder extending from the side flange and coupled to the end flange.