Battery pack
A battery pack includes battery cells arranged in a first direction, the battery cells each having a main surface, a first surface, and a second surface, main surfaces of battery cells that are adjacent to each other facing each other, and the first surface and the second surface respectively forming both ends of each of the battery cells in a second direction intersecting with the first direction; an insulating cap on the first surface and the second surface of the battery cell, the insulating cap extending from the first surface and the second surface onto a portion of the main surface of the battery cell and insulating the main surfaces of the battery cells adjacent to each other in the first direction; a bus bar on the insulating cap and electrically connecting the battery cells to each other; and a binding frame structurally binding the battery cells to each other.
1 . A battery pack, comprising:
a plurality of battery cells arranged in a first direction, each battery cell of the plurality of battery cells having a pair of main surfaces, a first surface, and a second surface, respective main surfaces of battery cells that are adjacent to each other facing each other, and the first surface and the second surface respectively forming opposite ends of each of the plurality of battery cells in a second direction intersecting with the first direction;
an insulating cap on each of the first surface and the second surface of each battery cell, the insulating cap extending from each of the first surface and the second surface onto an outermost portion of each of the pair of main surfaces of each battery cell and insulating the main surfaces of battery cells adjacent to each other in the first direction, and the insulating cap extending from the first surface of each battery cell being separated and spaced apart in the second direction from the insulating cap extending from the second surface of each battery cell;
a bus bar on the insulating cap and electrically connecting the plurality of battery cells to each other; and
a binding frame configured to structurally bind the plurality of battery cells to each other,
wherein each of the plurality of battery cells includes an electrode assembly inside a case, the case being a hollow case and including:
the pair of the main surfaces facing each other and occupying a relatively large area, the pair of main surfaces connecting the first surface and the second surface to each other,
a pair of side surfaces facing each other and occupying a smaller area than the pair of main surfaces, the pair of side surfaces connecting the first surface and the second surface to each other, and
first and second boards closing open ends at opposite ends of the hollow case, the first and second boards defining the first and second surfaces, respectively, and
wherein the outermost portion of each of the pair of main surfaces of each battery cell is a surface facing an exterior of the case.
2 . The battery pack as claimed in claim 1 , wherein the insulating cap is individually provided on each of the first surface and the second surface of each battery cell of the plurality of battery cells arranged in the first direction, such that each battery cell of the plurality of battery cells includes two separate and discrete insulating caps.
3 . The battery pack as claimed in claim 1 , wherein each of the pair of main surfaces and each of the side surfaces of each battery cell have an elongated shape extending lengthwise in the second direction.
4 . The battery pack as claimed in claim 1 , wherein the insulating cap includes:
a base portion on the first surface or the second surface of a corresponding battery cell;
a long-side portion extending from the base portion onto the pair of main surfaces of the corresponding battery cell; and
a short-side portion extending from the base portion onto the side surfaces of the corresponding battery cell.
5 . The battery pack as claimed in claim 4 , wherein the long-side portion and the short-side portion continuously surround edges of the first surface or the second surface of the corresponding battery cell.
6 . The battery pack as claimed in claim 1 , wherein:
the pair of main surfaces and the side surfaces are arranged to face each other, respectively, and
the pair of main surfaces and the side surfaces of each battery cell are outer surfaces of the hollow case of each battery cell and are continuously connected to each other.
7 . The battery pack as claimed in claim 6 , wherein each of the hollow cases includes a first opening and a second opening respectively at both ends of the hollow case, each hollow case being formed by cutting of a hollow member continuously extruded in the second direction.
8 . The battery pack as claimed in claim 1 , wherein a thickness of the hollow case is greater than a thickness of the first board and greater than a thickness of the second board.
9 . The battery pack as claimed in claim 1 , wherein the first surface and the second surface of each battery cell are outer surfaces of the first board and the second board, respectively.
10 . The battery pack as claimed in claim 1 , wherein:
each battery cell includes an electrode connected to the bus bar, and
the electrode of each battery cell includes a first electrode and a second electrode respectively protruding from the first surface and the second surface of each battery cell.
11 . The battery pack as claimed in claim 10 , wherein each insulating cap includes:
an electrode hole exposing the electrode of a corresponding battery cell; and
a bus bar guide configured to guide a position of the bus bar around the electrode hole.
12 . The battery pack as claimed in claim 11 , wherein:
each insulating cap further includes at least one fixing piece at an edge position thereof in a third direction intersecting with the first direction and the second direction, the at least one fixing piece and the electrode hole being on a same surface of the insulating cap, and
the electrode hole is at a central position of each insulating cap in the third direction.
13 . The battery pack as claimed in claim 12 , wherein:
the at least one fixing piece includes a plurality of fixing pieces arranged in the first direction to correspond to the plurality of battery cells, and
the binding frame is coupled to each of the plurality of fixing pieces while extending in the first direction and being in contact with the insulating cap of each battery cell of the plurality of battery cells.
14 . The battery pack as claimed in claim 12 , wherein:
the binding frame extends in the first direction and includes a first portion and a second portion bent with respect to each other,
the first portion includes a coupling position coupled with the at least one fixing piece, and
the second portion is bent from the first portion and protrudes toward the outside of the battery cell in the second direction.
15 . The battery pack as claimed in claim 12 , wherein the at least one fixing piece is integrally formed with a body of the insulating cap through insert injection molding.
16 . The battery pack as claimed in claim 12 , wherein each insulating cap further includes, together with the electrode hole, a bonding area at the central position thereof.
17 . The battery pack as claimed in claim 16 , wherein the electrode hole and the bonding area of the insulating cap are at different positions at the central position of each insulating cap.
18 . The battery pack as claimed in claim 17 , wherein:
the at least one fixing piece of each insulating cap includes a first fixing piece and a second fixing piece respectively at edge positions at both sides of each insulating cap in the third direction,
the electrode hole and the bonding area of each insulating cap are between the first fixing piece and the second fixing piece,
the electrode hole is at a position that is relatively closer to the first fixing piece, and
the bonding area is at a position that is relatively closer to the second fixing piece.
19 . The battery pack as claimed in claim 12 , wherein:
the bus bar is at a position of the electrode hole of each insulating cap,
the binding frame is at a position of the at least one fixing piece of each insulating cap, and
the battery pack further comprises a circuit unit on the bus bar and the binding frame, the circuit unit being connected to the bus bar.
20 . The battery pack as claimed in claim 1 , wherein the insulating cap is directly on each of the pair of main surfaces, the side surfaces, the first surface, and the second surface.
21 . The battery pack as claimed in claim 1 , wherein:
the insulating cap includes a side portion on the outermost portion of each of the pair of main surfaces of each battery cell, the side portion of the insulating cap being directly on each of the pair of main surfaces of each battery cell, and
the side portion of the insulating cap is in direct contact with the side portion of the insulating cap on an adjacent one of the plurality of battery cells, such that two adjacent ones of the plurality of battery cells include two insulating caps in direct contact with each other via the side portion, respectively.