The present invention provides a battery including a container, an electrode group including a positive electrode and a negative electrode, multiple current collecting tabs being extended from any one of the positive electrode and the negative electrode of the electrode group, and overlapped with one another; a lead bonded to at least one of the current collecting tabs by ultrasonic bonding, a lid configured to close an opening portion of the container, and an external terminal provided on the lid and connected to the at least one current collecting tab via the lead, in which the lead has a cross-sectional area that is increased in a middle of extension of the lead from an ultrasonic-bonded portion to the at least one of the current collecting tabs to the external terminal.

A temperature sensor is described for detecting a temperature of a battery cell. The temperature sensor has a first electrical conductor having a first end for connecting the first conductor to an element of the battery cell and having a second end for connecting the first conductor to a first input of a measuring device and a second electrical conductor having a first end for connecting the second conductor to the element of the battery cell and having a second end for connecting the second conductor to a second input of the measuring device.

A secondary battery includes an electrode assembly including a first non-coating portion and a second non-coating portion, a first current collector and a second current collector joined to the first non-coating portion and the second non-coating portion, respectively, a case that accommodates the electrode assembly, and a cap assembly that seals the case. The first current collector includes a first overlapping portion that overlaps and joins the first non-coating portion, the first overlapping portion having a length and a width, and the first non-coating portion having a length and a width. The length of the first overlapping portion is 30% to 70% of the length of the first non-coating portion, and the width of the first overlapping portion is 50% to 70% of the width of the first non-coating portion.

An exemplary busbar assembly includes a first layer, and a second layer having a portion that contacts the first layer and a portion that is spaced from the first layer to provide an opening between the first layer and the second layer. An exemplary method of managing thermal energy includes contacting a first layer and a second layer in a first area of a busbar, and separating, in a second area of the busbar, the first layer from the second layer to provide an opening between the first layer and the second layer.

An energy storage device (battery) includes an electrode assembly having current collecting tabs, each of which is formed of a plurality of projecting portions, projecting from a first straight line portion on one side in a stacking direction of electrode sheets. The electrode assembly is housed in a case (exterior body). The energy storage device further includes current collectors, which are electrically connected to the external terminals, disposed on the case. The current collectors, are connected to the current collecting tabs, arranged in a stacking direction of the electrode sheets, on a second straight line portion side where the projecting portions, are not formed.

A plurality of battery cells are connected by a busbar. Electrode terminals of the battery cells each include a protruding portion and a welding surface around the protruding portion. The busbar includes a welding plate portion being in surface-contact with the welding surface and having a cut-away portion for guiding the protruding portion, and an exposure gap that exposes the welding surface between the inner side of the cut-away portion and the protruding portion. The busbar is welded to the welding surface in a predetermined welding width (H) by both of a fillet weld part and a penetration welding portion such that the inner edge of the cut-away portion as the fillet weld part is welded to the welding surface, and the boundary between the busbar and the welding surface is welded by the penetration welding portion.

A connecting pole for a rechargeable battery is disclosed. The connecting pole (1) has a connecting section (2) in which a pole terminal can be attached to the connecting pole (1). The connecting pole (1) has an attachment section (3) in which the connecting pole (1) can be attached in a housing part (5) of the battery. The attachment section (3) has a labyrinth section (4). The outer wall (6) of the connecting pole (1) has at least one circumferential projection (7, 8) in the labyrinth section (4). The circumference of outer wall (6) of the connecting pole (1) increases in the direction pointing away from the connecting section (2) in a section of the labyrinth section (4) which is not provided with a circumferential projection (7, 8). Also disclosed is a rechargeable battery housing or a part of said rechargeable battery housing having at least one connecting pole.

A plurality of batteries is stacked, together with spacers, in a compressed state. Charging and discharging units are arranged facing lead terminals protruding from the batteries and are independently operable for the respective batteries. The charging and discharging units each independently include substantially V-like shaped power-side and measurement-side contact elements elastically supported by compression coil springs and having floating freedom. When the batteries are moved all together toward the charging and discharging units, front end surfaces of the lead terminals are pressed against and electrically connected to flat surfaces of the power-side and measurement-side contact elements. By this, it is possible to smoothly perform charging and discharging inspection on the batteries even when the lead terminals protruding from the battery package are subjected in advance to surface treatment.

A rechargeable battery includes: an electrode assembly; a case accommodating the electrode assembly; a cap plate sealing an opening of the case; and an electrode terminal at the cap plate and electrically coupled to the electrode assembly. The case includes: a first portion and a second portion opposite the first portion, at least one of the first and second portions being curved; and a reinforcing plate coupled to at least one of the first and second portions and having a curvature matching that of a corresponding curved one of the first and second portions.

A film-packaged cell has a flat rectangular shape where power-generating element is housed in packaging body together with an electrolytic solution, the film-packaged cell being sealed along four edges of the packaging body in a state where terminals are led out through one edge thereof. In an electrolyte injection step, the electrolytic solution is injected into bag-shaped body where three edges excluding the upper edge of the packaging body are sealed in an orientation where the terminals are protruding laterally, the electrolytic solution being injected from the side of the opening upper edge. In a partial sealing step performed before the electrolyte injection step, only one section of opening upper edge of the bag-shaped body near edge through which terminals are led out is partially sealed, thereby preventing the electrolytic solution from leaking out during electrolyte injection.