A secondary battery includes an electrode assembly having a first electrode tab protruding from a first side of the electrode assembly and a second electrode tab protruding from a second side of the electrode assembly; a case accommodating the electrode assembly and having a first opening at one side of the case and a second opening at another side of the case; a first terminal electrically coupled to the first electrode tab of the electrode assembly; a first cap plate sealing the first opening of the case and exposing the first terminal to the outside; a second terminal electrically coupled to the second electrode tab of the electrode assembly; and a second cap plate sealing the second opening of the case and exposing the second terminal to the outside, wherein the first electrode tab and the second electrode tab have bent portions.

A secondary battery includes an electrode assembly having a first electrode tab protruding from a first side of the electrode assembly and a second electrode tab protruding from a second side of the electrode assembly; a case accommodating the electrode assembly and having a first opening at one side of the case and a second opening at another side of the case; a first terminal electrically coupled to the first electrode tab of the electrode assembly; a first cap plate sealing the first opening of the case and exposing the first terminal to the outside; a second terminal electrically coupled to the second electrode tab of the electrode assembly; and a second cap plate sealing the second opening of the case and exposing the second terminal to the outside, wherein the first electrode tab and the second electrode tab have bent portions.

A secondary battery includes: an electrode assembly having a long side and a short side; a retainer coupled to the short side of the electrode assembly; an insulating sheet surrounding a periphery of the electrode assembly and the retainer; and a case accommodating the electrode assembly, the retainer, and the insulating sheet.

A secondary battery includes an electrode assembly including a current collection tab protruding to one side; a case including a main body having an accommodating part accommodating the electrode assembly, and a cover covering the main body; and an electrode lead electrically connected to the current collection tab and drawn out of the case, wherein the current collection tab is bent twice, and a length of the current collection tab is twice a thickness of the electrode assembly.

A secondary battery includes: an electrode assembly; a case accommodating the electrode assembly; a cap plate sealing the case; and a current collector plate welded between the electrode assembly and the case or between the electrode assembly and the cap plate. The current collector plate has a slit therein.

A secondary battery includes: an electrode assembly; a case accommodating the electrode assembly; a cap plate sealing the case; and a current collector plate welded between the electrode assembly and the case or between the electrode assembly and the cap plate. The current collector plate has a slit therein.

A secondary battery includes an electrode assembly including a first electrode plate, a separator, and a second electrode plate, a lower case in which the electrode assembly is accommodated and electrode tabs are provided on sidewalls opposing each other, an upper case coupled to the lower case, and an outer casing disposed to surround the lower case and the upper case. The electrode assembly is provided with a first uncoated electrode portion extending from the first electrode plate and a second uncoated electrode portion extending from the second electrode plate, and the first and second uncoated electrode portions are bent and connected to the electrode tab of the lower case.

A secondary battery includes an electrode assembly including a first electrode plate, a separator, and a second electrode plate, a lower case in which the electrode assembly is accommodated and electrode tabs are provided on sidewalls opposing each other, an upper case coupled to the lower case, and an outer casing disposed to surround the lower case and the upper case. The electrode assembly is provided with a first uncoated electrode portion extending from the first electrode plate and a second uncoated electrode portion extending from the second electrode plate, and the first and second uncoated electrode portions are bent and connected to the electrode tab of the lower case.

A secondary battery includes an electrode body, a battery case, and an electrode terminal. The electrode body has a foil collecting portion. The electrode terminal corresponding to at least one of a positive electrode and a negative electrode is electrically connected to the foil collecting portion via a current collector terminal. The current collector terminal is joined to the foil collecting portion. The foil collecting portion has a joining mark composed of a plurality of recesses on a surface on an opposite side of the foil collecting portion from a surface joined to the current collector terminal. The joining mark has two corners on an inner side of the electrode body and two corners on an outer side of the electrode body, and only the two corners on the inner side of the electrode body have a chamfered shape.

According to an embodiment, there are provided a method for manufacturing a battery module for an electric vehicle and a battery module manufactured by the method. The method comprises preparing an electrode assembly, the electrode assembly including a plurality of electrode plates, a plurality of electrode tabs, and a separator, forming a plurality of electrode leads by friction-welding a copper piece and an aluminum piece, attaching a sealing film to each of the plurality of electrode leads, packing the electrode assembly in a pouch case, with the aluminum piece exposed to an outside of the pouch case, injecting an electrolyte into the pouch case, sealing the pouch case to form each of the plurality of battery cells, stacking the plurality of battery cells one over another, and connecting the aluminum pieces of the plurality of battery cells to each other via a sensing bus bar.