A film (200) includes a first accommodation portion (210) and a second accommodation portion (220). The first accommodation portion (210) covers one side of the battery element (100). The second accommodation portion (220) covers the other side opposite to the one side of the battery element (100). A recessed portion (232) is formed at a portion of the film (200) folded from one of the first accommodation portion (210) and the second accommodation portion (220) to the other. The recessed portion (232) is recessed towards the battery element (100). The recessed portion (232) extends along one direction orthogonal to a direction from the one side toward the other side of the battery element (100).

A pouch-type secondary battery includes an electrode assembly including a first electrode plate, a separator, and a second electrode plate; and a pouch film in which the electrode assembly is accommodated, wherein the pouch film includes a first side sealing portion from which a negative electrode lead connected to the electrode assembly protrudes, a second side sealing portion from which a positive electrode lead connected to the electrode assembly protrudes, and an upper sealing portion having both end portions connected to the first and second side sealing portions, and the pouch film includes a folded portion disposed on an end of the first side sealing portion and an end of the second side sealing portion, and folded toward a bottom portion of the pouch film, wherein the folded portion is folded in one direction.

Disclosed are a secondary battery and a secondary battery case.

According to one aspect of the present invention, provided is a case for a secondary battery including: a first recess part having a recessed shape; a second recess part opposite the first recess part and having a recessed shape; a circumferential part configured to surround a circumference of each of the first recess part and the second recess part when the case is unfolded; and a connection part provided between the first recess part and the second recess part to connect the first recess part to the second recess part, wherein, when the case is unfolded, the connection part includes: a first connection surface inclined in a first direction from one end of the first recess part; and a second connection surface inclined in the first direction from one end of the second recess part.

Disclosed are a secondary battery and a secondary battery case.

According to one aspect of the present invention, provided is a case for a secondary battery including: a first recess part having a recessed shape; a second recess part opposite the first recess part and having a recessed shape; a circumferential part configured to surround a circumference of each of the first recess part and the second recess part when the case is unfolded; and a connection part provided between the first recess part and the second recess part to connect the first recess part to the second recess part, wherein, when the case is unfolded, the connection part includes: a first connection surface inclined in a first direction from one end of the first recess part; and a second connection surface inclined in the first direction from one end of the second recess part.

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

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

A case having elasticity corresponding to expansion and contraction of a stacked body housed therein and a method for manufacturing the same, a method for inserting the stacked body into the case, and a cell stack using the case are provided. A case configured to house a stacked body includes two opposed contact parts in contact with the stacked body, and two spring structures connecting the two contact parts with each other.

Provided is a laminate battery in which a short circuit between a negative electrode active material and a positive electrode due to expansion of the negative electrode active material during discharging is prevented.

A laminate battery includes a battery case that serves as an outer case. The laminate battery includes an inner case within a battery case 11, and the inner case is formed of a positive electrode storage case and a separator. An inside of the inner case serves as a positive electrode storage portion that stores a positive electrode. An outside of the inner case serves as a negative electrode storage portion that stores a negative electrode. The negative electrode uses a particulate negative electrode active material (e.g., zinc or zinc oxide).

Disclosed is a flexible secondary battery comprising a lithium metal coated wire, a positive electrode wire spirally wound around an outer surface of the lithium metal coated wire, spaced apart at a predetermined interval, the positive electrode wire including a first porous coating layer formed on an outer surface, and a negative electrode wire spirally wound around the outer surface of the lithium metal coated wire in an alternating manner with the wound positive electrode wire corresponding to the predetermined interval, the negative electrode wire including a second porous coating layer formed on an outer surface.

Disclosed is a flexible secondary battery comprising a lithium metal coated wire, a positive electrode wire spirally wound around an outer surface of the lithium metal coated wire, spaced apart at a predetermined interval, the positive electrode wire including a first porous coating layer formed on an outer surface, and a negative electrode wire spirally wound around the outer surface of the lithium metal coated wire in an alternating manner with the wound positive electrode wire corresponding to the predetermined interval, the negative electrode wire including a second porous coating layer formed on an outer surface.