A method includes, by a folding station: receiving an anode assembly including anode collectors connected by anode interconnects and coated with a separator; receiving a cathode assembly including cathode collectors connected by cathode interconnects; locating a first anode collector over a folding stage; locating a first cathode collector over the first anode collector to form a first battery cell between the first anode collector and the first cathode collector; folding a first anode interconnect to locate a second anode collector over the first cathode collector to form a second battery cell between the first cathode collector and the second anode collector; folding a first cathode interconnect to locate a second cathode collector over the second anode collector to form a third battery cell between the second anode collector and the second cathode collector; wetting the separator with solvated ions; and loading the anode and cathode assemblies into a battery housing.

A method includes, by a folding station: receiving an anode assembly including anode collectors connected by anode interconnects and coated with a separator; receiving a cathode assembly including cathode collectors connected by cathode interconnects; locating a first anode collector over a folding stage; locating a first cathode collector over the first anode collector to form a first battery cell between the first anode collector and the first cathode collector; folding a first anode interconnect to locate a second anode collector over the first cathode collector to form a second battery cell between the first cathode collector and the second anode collector; folding a first cathode interconnect to locate a second cathode collector over the second anode collector to form a third battery cell between the second anode collector and the second cathode collector; wetting the separator with solvated ions; and loading the anode and cathode assemblies into a battery housing.

A method of manufacturing a secondary battery including an electrode body element fabricating step in which a first electrode body element including a positive electrode plate and a negative electrode plate, and a second electrode body element including a positive electrode plate and a negative electrode plate are fabricated, a tab-connecting step in which a first positive electrode tab group of the first electrode body element and a second positive electrode tab group of the second electrode body element are connected to a second positive electrode collector, and a first negative electrode tab group of the first electrode body element and a second negative electrode tab group of the second electrode body element are connected to a second negative electrode collector, and an electrode body fabricating step in which, after the tab-connecting step, the first electrode body element and the second electrode body element are unified.

A method of manufacturing a secondary battery including an electrode body element fabricating step in which a first electrode body element including a positive electrode plate and a negative electrode plate, and a second electrode body element including a positive electrode plate and a negative electrode plate are fabricated, a tab-connecting step in which a first positive electrode tab group of the first electrode body element and a second positive electrode tab group of the second electrode body element are connected to a second positive electrode collector, and a first negative electrode tab group of the first electrode body element and a second negative electrode tab group of the second electrode body element are connected to a second negative electrode collector, and an electrode body fabricating step in which, after the tab-connecting step, the first electrode body element and the second electrode body element are unified.

An electrochemical apparatus includes an electrode assembly. The electrode assembly includes a first electrode plate and a first tab group electrically connected to the first electrode plate, and an end of the electrode assembly includes a reusable region. The first electrode plate includes a first region located at an end of the first electrode plate and a second region connected to the first region, a thickness of the first region is less than a thickness of the second region, and the first region is disposed within the reusable region. The first tab group includes a first connecting portion located at an end of a first tab and a first bending portion connected to the first connecting portion and located on a side face of the electrode assembly, the first bending portion is disposed within the reusable region.

An electrochemical apparatus includes an electrode assembly. The electrode assembly includes a first electrode plate and a first tab group electrically connected to the first electrode plate, and an end of the electrode assembly includes a reusable region. The first electrode plate includes a first region located at an end of the first electrode plate and a second region connected to the first region, a thickness of the first region is less than a thickness of the second region, and the first region is disposed within the reusable region. The first tab group includes a first connecting portion located at an end of a first tab and a first bending portion connected to the first connecting portion and located on a side face of the electrode assembly, the first bending portion is disposed within the reusable region.

Provided is a technique to reduce voids between an electrode tab and a current collecting unit in a portion where the electrode tab and the current collecting unit are welded. The secondary battery manufacturing method disclosed herein is a method of manufacturing a secondary battery including an electrode body having an electrode tab and a current collecting unit electrically connected to the electrode body. This method includes: welding between the electrode tab and the current collecting unit, by sandwiching the electrode tab between a transparent material and the current collecting unit and then applying laser to penetrate the transparent material.

Provided is a technique to reduce voids between an electrode tab and a current collecting unit in a portion where the electrode tab and the current collecting unit are welded. The secondary battery manufacturing method disclosed herein is a method of manufacturing a secondary battery including an electrode body having an electrode tab and a current collecting unit electrically connected to the electrode body. This method includes: welding between the electrode tab and the current collecting unit, by sandwiching the electrode tab between a transparent material and the current collecting unit and then applying laser to penetrate the transparent material.

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.

An interconnect board (ICB) assembly suitable for a battery module of horizontal stack structure including unidirectional battery cells stacked with cell leads facing each other includes an ICB frame in which cell leads of unidirectional battery cells are configured to be received such that the unidirectional battery cells having the cell leads at one end are configured to be placed facing each other with the cell leads facing each other, and busbars formed in the ICB frame and configured to be electrically connected to the cell leads, wherein the ICB frame is configured to be connected to another ICB frame with a hinge structure in a lengthwise direction of the ICB frame. A battery module including the ICB assembly and a method for fabricating the battery module are also provided.