JPWO2020027173A1 - Battery pack - Google Patents

Abstract

The battery pack (10) has a plurality of cell holders (22a) that electrically hold a plurality of battery cells (20) side by side in the row direction and the column direction, and a plurality of terminal surfaces (18) of the battery cells (20) that are electrically connected to each other. The lead plate (24) of the above is provided. The cell holder (22a) has a set of exposed side surfaces (30) provided with openings (36) that expose the terminal surfaces (18) on both axial directions of the battery cell (20), and the battery cell (20). ) Are arranged in a zigzag manner in the row direction and held. In the plurality of terminal surfaces (18) arranged on the exposed side surface (30), the positive and negative of the terminal surfaces (18) adjacent to each other in the row direction are equal, and the positive and negative of the terminal surfaces (18) adjacent to each other in the column direction are different. The plurality of lead plates (24) are arranged so as to be spaced apart from each other in the column direction with respect to the exposed side surface (30), and the side (60) in the row direction is formed so as to extend in the row direction.

Description

The present invention relates to a battery pack including a cell holder that holds a plurality of battery cells and a lead plate that electrically connects the terminal surfaces of the plurality of battery cells.

For example, a battery pack that is detachably mounted on an electric vehicle or the like is known as described in Japanese Patent No. 4761726. Specifically, the battery pack includes a cell holder that holds a plurality of columnar battery cells side by side in the row direction and the column direction so that their terminal surfaces are arranged in the same plane, and a plurality of battery cells. It is provided with a plurality of lead plates for electrically connecting the terminal surfaces to each other. The cell holder protects the battery cells by arranging a plurality of battery cells in a zigzag direction in the row direction to maintain the density of the battery cells held in the cell holder and prevent the battery cells from being crushed by an external force. ing. In this type of battery pack, the side of the lead plate in the row direction is also zigzag as the terminal surfaces of the battery cells are arranged in a zigzag manner in the row direction.

In order to obtain a lead plate having a complicated shape having zigzag-shaped sides with a desired processing accuracy, an expensive mold having a complicated shape or the like is required, and there is a concern that the manufacturing cost will increase. Further, when such a lead plate is punched from the flat plate, the ratio of the unused portion that does not form the lead plate to the entire flat plate becomes large, so that the material yield decreases, and there is a concern that the manufacturing cost also increases. ..

Therefore, a main object of the present invention is to provide a battery pack capable of protecting a battery cell with a simple configuration without increasing the manufacturing cost.

One aspect of the present invention is to arrange a battery cell which is columnar and has terminal surfaces having different positive and negative ends in the axial direction, and a plurality of the battery cells so that the terminal surfaces are arranged on the same plane. A battery pack including a cell holder that holds the cells side by side in the direction and the column direction, and a plurality of lead plates that electrically connect the terminal surfaces arranged in the row direction to each other, wherein the cell holder is a plurality of the batteries. It has a set of exposed side surfaces provided with openings for exposing the terminal surfaces on both sides of the cell in the axial direction from the cell holder, and the center of the terminal surfaces adjacent to the row direction is one side in the column direction. The plurality of terminal surfaces arranged on the exposed side surface are held so as to be alternately displaced from each other and the other side, and the positive and negative of the terminal surfaces adjacent to the row direction are equal to each other and the column direction. The positive and negative of the terminal surface adjacent to the terminal surface are different, and the plurality of lead plates are arranged so as to be spaced apart from each other in the column direction with respect to the exposed side surface and extend in the row direction. NS.

In this battery pack, since the lead plate extends in the row direction, for example, unlike the zigzag-shaped lead plate, a simple mold is used to obtain the lead plate with high accuracy, and the lead plate is punched out from the flat plate. It is possible to improve the material yield by reducing the proportion of unused portion of. Further, in this battery pack, a plurality of battery cells are arranged so that the centers of terminal surfaces adjacent to each other in the row direction are alternately shifted to one side and the other side in the column direction, in other words, a plurality of battery cells are arranged in the row direction. Arrange in a zigzag pattern. Therefore, even if the battery cells are held at a high density in the cell holder, the battery cells can be made difficult to be crushed by an external force.

From the above, according to the battery pack of the present invention, it is possible to protect the battery cell with a simple configuration without increasing the manufacturing cost.

It is a schematic perspective view of the battery pack which concerns on embodiment of this invention. It is an exploded perspective view of the battery core pack of FIG. It is an exploded perspective view of the cell holder of FIG. It is explanatory drawing explaining the relationship between the terminal surface of the 1st exposed side surface of a cell holder, and a lead plate. It is explanatory drawing explaining the relationship between the terminal surface of the 2nd exposed side surface of a cell holder, and a lead plate. FIG. 4 is a cross-sectional view taken along the line VI-VI of FIG. FIG. 4 is a cross-sectional view taken along the line VII-VII of FIG. The relationship between the radius r of the welded portion, the diameter D of the battery cell, the distance GP between the outer peripheral surfaces of the battery cells adjacent in the column direction, and the distance CL between the row-direction sides of the lead plates adjacent in the column direction. It is explanatory drawing to explain. It is sectional drawing explaining the lead plate which concerns on the modification.

A suitable embodiment of the battery pack according to the present invention will be described in detail with reference to the accompanying drawings. In the following figures, components having the same or similar functions and effects may be designated by the same reference numerals, and repeated description may be omitted.

The battery pack 10 shown in FIG. 1 can be suitably applied to, for example, a portable driving power source that is detachably mounted on an electric vehicle (not shown) such as an electrically assisted bicycle, an electric motorcycle, or an electric vehicle. .. Therefore, an example in which the battery pack 10 is mounted on the electric vehicle will be described below. However, the battery pack 10 is not particularly limited to this, and can be applied to various devices that require electric power. Further, in the following description, for convenience of explanation, the arrow Z1 side of FIG. 1 will be referred to as the upper side in the vertical direction and the arrow Z2 side will be referred to as the lower side in the vertical direction. You may.

As shown in FIG. 1, the battery pack 10 is housed in a case 16 in which a battery core pack 12, a battery management device (BMU) 14, and a connector portion (not shown) form an exterior. In FIG. 1, a part of the case 16 is shown by a chain double-dashed line for easy understanding, and the components arranged inside the case 16 are shown.

As shown in FIG. 2, the battery core pack 12 has a columnar battery cell 20 provided with terminal surfaces 18 having different positive and negative positive and negative directions at both ends in the axial direction (arrows X1 and X2 directions), and the terminal surfaces 18 are on the same plane. Two cell holders 22a and 22b that hold the plurality of battery cells 20 side by side in the row direction (arrows Y1 and Y2 directions) and the column direction (arrows Z1 and Z2 directions) so as to be arranged in the row direction at least in the row direction. A plurality of lead plates 24 for electrically connecting the terminal surfaces 18 to each other are provided. In FIG. 2, the horizontal direction when viewed from the axial direction of the battery cell 20 is the row direction, and the vertical direction perpendicular to the horizontal direction is the column direction.

As shown in FIGS. 3 to 5, in the battery cell 20, one of the terminal surfaces 18 on both sides in the axial direction is the positive electrode terminal surface 26 and the other is the negative electrode terminal surface 28. A preferred type of battery cell 20 includes, but is not limited to, a lithium ion secondary battery, and for example, a secondary battery such as a nickel hydrogen battery or a nickel cadmium battery may be used.

As shown in FIG. 2, since the two cell holders 22a and 22b are configured in substantially the same manner as each other, the description of the other cell holder 22b will be omitted with the description of one cell holder 22a for a specific configuration. The cell holder 22a has a first exposed side surface 32 and a second exposed side surface 34 as a set of exposed side surfaces 30 that expose the terminal surfaces 18 on both sides in the axial direction of the plurality of battery cells 20 from the cell holder 22a, respectively. Hereinafter, when the first exposed side surface 32 and the second exposed side surface 34 are not particularly distinguished, they are collectively referred to as an exposed side surface 30. A circular opening 36 corresponding to the shape of the terminal surface 18 is provided on the exposed side surface 30, and the terminal surface 18 is exposed to the outside of the cell holder 22a through the opening 36.

Further, the cell holder 22a holds a plurality of battery cells 20 arranged side by side in a zigzag manner in the row direction. As a result, as shown in FIGS. 4 and 5, the center O of the terminal surface 18 adjacent in the row direction is located on one side (arrow Z1 side) and the other side (arrow Z2 side) in the column direction on the exposed side surface 30. They are arranged alternately in a staggered manner. In the present embodiment, the cell holder 22a holds seven rows of battery cells 20 composed of R1 to R7, and each row of R1 to R7 is composed of six terminal surfaces 18 arranged in a zigzag manner as described above. There is. That is, the terminal surface 18 of each row has three first terminal surfaces 38 whose center O is arranged on one side in the column direction (arrow Z1 side) and the center O on the other side in the column direction (arrow Z2 side). It has three second terminal surfaces 40 to be arranged. The number of rows of the battery cell 20 held by the cell holder 22a is not limited to seven, and the number of terminal surfaces 18 constituting each row is not limited to six.

The terminal surfaces 18 arranged on the exposed side surface 30 have the same positive and negative in the row direction and different positive and negative in the column direction. In the first exposed side surface 32 of the present embodiment, as shown in FIG. 4, the rows of R1, R3, R5, and R7 are composed of the negative electrode terminal surfaces 28, and the rows of R2, R4, and R6 are composed of the positive electrode terminal surfaces 26. Will be done. Therefore, on the second exposed side surface 34, which is the back surface of the first exposed side surface 32, as shown in FIG. 5, the rows of R1, R3, R5, and R7 are composed of the positive electrode terminal surfaces 26, and R2, R4, and R6. The row is composed of the negative electrode terminal surface 28.

As shown in FIG. 3, the cell holder 22a can be configured by, for example, combining a first member 42 having a first exposed side surface 32 and a second member 44 having a second exposed side surface 34. The first member 42 and the second member 44 have a plurality of holding holes 46, and hold the battery cell 20 in a state of being inserted into the holding holes 46, respectively. An opening 36 that opens to the first exposed side surface 32 is provided at one end of the holding hole 46 of the first member 42, and an opening 36 opens to the second exposed side surface 34 at one end of the holding hole 46 of the second member 44. An opening 36 is provided.

For example, after interposing the battery cell 20 between the first member 42 and the second member 44 separated in the axial direction (arrows X1 and X2 directions), the battery cell 20 is inserted into the holding hole 46 while being inserted. By connecting the first member 42 and the second member 44 so as to be close to each other in the axial direction, a cell holder 22a for holding a plurality of battery cells 20 is formed.

As shown in FIGS. 4 and 6, a part of the first exposed side surface 32 on the arrow Z2 side of the opening 36 that exposes the second terminal surface 40 of R1, R3, and R5 is covered with the insulating portion 48, respectively. ing. As shown in FIGS. 4 and 7, a part of the first exposed side surface 32 on the arrow Z1 side of the opening 36 that exposes the first terminal surface 38 of R2, R4, and R6 is covered with the insulating portion 48, respectively. ing.

As shown in FIGS. 5 and 6, a part of the second exposed side surface 34 on the arrow Z2 side of the opening 36 that exposes the second terminal surface 40 of R2, R4, and R6 is covered with the insulating portion 48, respectively. ing. As shown in FIGS. 5 and 7, a part of the second exposed side surface 34 on the arrow Z1 side of the opening 36 that exposes the first terminal surface 38 of R3, R5, and R7 is covered with the insulating portion 48, respectively. ing.

As shown in FIGS. 6 and 7, the insulating portion 48 projects outward in the axial direction of the cell holder 22a from the opening 36 adjacent in the row direction not covered by the insulating portion 48 by the thickness thereof. ing. Therefore, a step 48a is formed between the portion of the opening 36 covered by the insulating portion 48 and the other opening 36 that is not covered by the insulating portion 48 and is adjacent in the row direction.

Further, the insulating portion 48 is provided with an insulating wall 50 that projects outward in the axial direction of the cell holder 22a from an end portion of the insulating portion 48 facing the center side of the opening 36 that covers a part thereof. The insulating walls 50 are ridges extending linearly along the row direction, and three insulating walls 50 are provided at intervals in the column direction with respect to each of the first exposed side surface 32 and the second exposed side surface 34. ing.

As shown in FIGS. 4 and 5, the side wall portions 52 of the ridges extending linearly along the column direction are formed at the edges of both ends of the first exposed side surface 32 and the second exposed side surface 34 in the row direction. Each is provided. In the present embodiment, the protruding heights (heights in the directions of arrows X1 and X2) of the side wall portion 52 and the insulating wall 50 are set in the same manner. Further, the side wall portions 52 provided on the arrow Y1 side of the first exposed side surface 32 and the second exposed side surface 34 are provided with a plurality of grooves 56 into which the connection end portions 54 of the lead plate 24, which will be described later, are inserted. There is.

The plurality of lead plates 24 are arranged at intervals in the row direction with respect to the exposed side surface 30, and the welded portions 58 having a substantially circular shape in the axial direction of the battery cell 20 (see FIGS. 4 and 5). It is electrically connected to the terminal surface 18 via. Further, the sides 60 of the lead plate 24 in the row direction extend in a straight line (row direction) orthogonal to the column direction.

Specifically, as shown in FIG. 2, the lead plate 24 has output lead plates 62a and 62b and intermediate lead plates 64a, 64b, 64c, 64d, 64e and 64f. Each of the output lead plates 62a and 62b connects a row of terminal surfaces 18 arranged at the end of the exposed side surface 30 in the column direction in parallel. Further, each of the output lead plates 62a and 62b has tab portions 66a and 66b that enable the battery cell 20 held in the cell holder 22a to be electrically connected to the outside of the cell holder 22a. The intermediate lead plates 64a, 64b, 64c, 64d, 64e, 64f connect the terminal surfaces 18 of the two rows in series in the column direction and in parallel in the row direction.

That is, as shown in FIG. 4, on the first exposed side surface 32, R1 which is one row on one end side (arrow Z1 side) in the column direction is connected to one output lead plate 62a, and the remaining rows Two adjacent rows of R2 to R7 are connected to three intermediate lead plates 64a, 64b, and 64c, respectively.

Therefore, the terminal surfaces 18 constituting R1 are connected in parallel by the output lead plate 62a. Further, the terminal surfaces 18 constituting R2 and R3 are connected in parallel in the row direction by the intermediate lead plate 64a and are connected in series in the column direction. The terminal surfaces 18 constituting R4 and R5 are connected in parallel and in series by an intermediate lead plate 64b, and the terminal surfaces 18 constituting R6 and R7 are connected in parallel and in series by an intermediate lead plate 64c, respectively.

As shown in FIG. 5, in the second exposed side surface 34, R7, which is one row on the other end side (arrow Z2 side) in the column direction, is connected to one output lead plate 62b, and R1 which is the remaining row. Two adjacent rows of ~ R6 are connected to three intermediate lead plates 64d, 64e, and 64f, respectively.

Therefore, the terminal surfaces 18 constituting R7 are connected in parallel by the output lead plate 62b. Further, the terminal surfaces 18 constituting R1 and R2 are connected to each other by the intermediate lead plate 64d, and the terminal surfaces 18 forming R3 and R4 are connected to each other by the intermediate lead plate 64e. The intermediate lead plate 64f connects them in parallel and in series, respectively.

By providing the lead plate 24 on the first exposed side surface 32 and the second exposed side surface 34 as described above, all the battery cells 20 held in the cell holder 22a have the terminal surfaces 18 in each row parallel to each other. At the same time, adjacent rows are connected in series.

As shown in FIG. 4, in the first exposed side surface 32, the output lead plate 62a covers the entire output lead plate 62a with the first terminal surface 38 in R1 as the covering side terminal surface 68. Further, the output lead plate 62a covers more than half and less than the whole in the row direction with the second terminal surface 40 in R1 as the exposed side terminal surface 70. As a result, of the set of sides 60 in the row direction of the output lead plate 62a, one of the sides facing the intermediate lead plate 64a (arrow Z2 side) is arranged so as to cross the exposed side terminal surface 70.

The intermediate lead plate 64a covers the entire surface of the second terminal surface 40 in R2 and the first terminal surface 38 in R3 as the covering side terminal surface 68. Further, the intermediate lead plate 64a covers more than half of each row direction and less than the whole, with the first terminal surface 38 in R2 and the second terminal surface 40 in R3 as exposed side terminal surfaces 70. As a result, each of the set of rows-wise sides 60 of the intermediate lead plate 64a is arranged so as to cross the exposed terminal surface 70. The intermediate lead plate 64b is also arranged in the same manner with respect to R4 and R5, and the intermediate lead plate 64c is also arranged in the same manner with respect to R6 and R7.

As shown in FIG. 5, in the second exposed side surface 34, the intermediate lead plate 64d covers the entire second terminal surface 40 in R1 and the first terminal surface 38 in R2 as the covering side terminal surface 68. .. Further, the intermediate lead plate 64d covers more than half of each row direction and less than the whole, with the first terminal surface 38 in R1 and the second terminal surface 40 in R2 as exposed side terminal surfaces 70. As a result, each of the set of side 60s in the row direction of the intermediate lead plate 64d is arranged so as to cross the exposed side terminal surface 70. The intermediate lead plate 64e is also arranged in the same manner with respect to R3 and R4, and the intermediate lead plate 64f is also arranged in the same manner with respect to R5 and R6.

Further, the output lead plate 62b is arranged so that the second terminal surface 40 in R7 becomes the covering side terminal surface 68 and the first terminal surface 38 in R7 becomes the exposed side terminal surface 70. Further, of the set of sides 60 in the row direction of the output lead plate 62b, one of the sides facing the intermediate lead plate 64f (arrow Z1 side) is arranged so as to cross the exposed side terminal surface 70.

As shown in FIG. 8, one side (for example, the output lead plate 62a in FIG. 4) of a set of lead plates 24 adjacent to each other in the row direction is used as the first lead plate 72, and the other side (for example, the intermediate lead in FIG. 4) is used. Let the plate 64a) be the second lead plate 74. Further, one side (for example, R1 in FIG. 4) of the two rows of terminal surfaces 18 adjacent to each other in the column direction is designated as the first row Ra, and the other side (for example, R2 in FIG. 4) is designated as the second row Rb. The lead plate 72 covers the entire covered terminal surface 68 of the first row Ra and more than half and less than the entire exposed terminal surface 70 of the first row Ra, and the second lead plate 74 covers the entire exposed side terminal surface 70 of the first row Ra. It is assumed that the entire covered terminal surface 68 and half or more and less than half of the exposed terminal surface 70 of the second row Rb are covered. In FIG. 8, the insulating portion 48, the insulating wall 50, and the convex portion of the positive electrode terminal surface 26 are not shown.

At this time, the first lead plate 72 faces the portion of the exposed terminal surface 70 of the second row Rb exposed from the second lead plate 74 via the insulating portion 48 (see FIGS. 4 to 7). The second lead plate 74 faces a portion of the exposed terminal surface 70 of the first row Ra exposed from the first lead plate 72 via an insulating portion 48 (see FIGS. 4 to 7). As a result, it is possible to prevent the first lead plate 72 from being electrically connected to the exposed terminal surface 70 of the second row Rb, and the second lead plate 74 is electrically connected to the exposed terminal surface 70 of the first row Ra. It is possible to avoid being connected to the target.

Further, the welded portion 58 is provided substantially at the center of the terminal surface 18, the radius of the welded portion 58 is r, the diameter of the battery cell 20 is D, and the distance between the outer peripheral surfaces of the battery cells 20 adjacent to each other in the row direction. Is GP, and the distance between the side 60s in the row direction of the lead plates 24 adjacent to each other in the column direction is CL, and the relationship of r ≦ ((D / 2 + GP / 2) -CL) / 2 is satisfied.

Further, the distance between the center O of the exposed side terminal surface 70 of the first row Ra and the side 60 of the first lead plate 72 in the row direction is L1, and the center O of the exposed side terminal surface 70 of the second row Rb and the second row Rb. When the distance of the lead plate 74 from the side 60 in the row direction is L2, the relationship of L1 = L2 = ((D / 2 + GP / 2) -CL) / 2 is satisfied.

As shown in FIGS. 4 and 8, when the first lead plate 72 is the intermediate lead plate 64a, the second lead plate 74 is the intermediate lead plate 64b, the first row Ra is R3, and the second Line Rb is R4. As a specific combination of "first lead plate 72, second lead plate 74, first row Ra, second row Rb" other than the above, in the first exposed side surface 32 of FIG. 4, "intermediate lead plate 64b, "Intermediate lead plates 64c, R5, R6" are mentioned, and in the second exposed side surface 34 of FIG. 5, "intermediate lead plate 64d, intermediate lead plate 64e, R2, R3", "intermediate lead plate 64e, intermediate lead plate 64f," "R4, R5", "intermediate lead plate 64f, output lead plate 62b, R6, R7" can be mentioned.

As shown in FIGS. 4 to 7, the insulating wall 50 provided in the insulating portion 48 projects between the side 60s of the lead plates 24 adjacent to each other in the row direction. That is, the insulating wall 50 is interposed between the sides 60 in the row direction. As a result, the lead plates 24 adjacent to each other are insulated from each other.

Slits 76 are provided in the row direction on the portion of the lead plate 24 facing the insulating portion 48. Further, as shown in FIG. 1 and the like, each of the side 78 in the column direction on the arrow Y1 side of the lead plate 24 is provided with a projecting end portion 54 that protrudes outward in the row direction and is inserted into the groove 56. ing. By connecting lead wires and the like (not shown) to these connection end portions 54, the plurality of lead plates 24 are connected to the connector portion via the BMU 14.

As shown in FIG. 2, the two cell holders 22a and 22b configured as described above are arranged so that the second exposed side surface 34 sides of each other face each other via the insulating member 80. The intermediate lead plates 64d, 64e, and 64f provided on the second exposed side surfaces 34 facing each other are insulated from each other by the insulating member 80. Further, the output lead plates 62b provided on the second exposed side surfaces 34 facing each other are electrically connected to each other via the tab portion 66b. As a result, the terminal surfaces 18 on the other end side (arrow Z2 side, R7 in FIG. 5) of the two cell holders 22a and 22b in the row direction are connected in series.

The output lead plate 62b of the cell holder 22a, the tab portion 66b, and the output lead plate 62b of the cell holder 22b are integrally formed from one metal plate. The tab portion 66b extends from substantially the center of the output lead plate 62b of the cell holder 22a in the row direction, curves below the insulating member 80, and faces substantially the center of the output lead plate 62b of the cell holder 22b in the row direction.

The outputs (voltage and current) of the plurality of battery cells 20 held in the cell holders 22a and 22b are the tab portions of a set of output lead plates 62a provided on the first exposed side surface 32 side of each of the cell holders 22a and 22b. It is possible to obtain it via 66a. The tab portion 66a is formed from one of the side 60 of the set of output lead plates 62a in the row direction that is not adjacent to the intermediate lead plate 64a (arrow Z1 side) toward the upper side of the cell holders 22a and 22b, respectively. It is postponed.

In the present embodiment, the tab portions 66a and 66b are provided at substantially the center of the row direction of the side 60 in the row direction of the output lead plates 62a and 62b, respectively, but the present invention is not particularly limited to this, and for example. , The output lead plates 62a, 62b may be provided on the side 78 or the like in the row direction.

As shown in FIG. 1, the BMU 14 is arranged above the battery core pack 12 in the case 16. The BMU 14 may be provided below or to the side of the battery core pack 12 in the case 16. The BMU 14 is, for example, a state of the battery core pack 12 detected from the temperature, voltage, and the like of the battery cell 20, the control unit that controls the charging and discharging of the battery core pack 12, the communication unit that communicates with the electric vehicle and the charging device, and the like. (Neither is shown).

The case 16 can be formed of, for example, a metal such as aluminum, a resin (including a fiber reinforced resin), or the like. Further, the case 16 has a bottom case 82 that covers the bottom surface of the battery core pack 12, an outer shell case 84 that covers the side surface of the battery core pack 12, and a top case 86 that covers the upper surface of the battery core pack 12.

The bottom case 82 is a housing having an open upper end, and the above-mentioned connector portion and the like are housed therein. The connector portion is exposed to the outside of the case 16 through, for example, a notch formed in the bottom wall of the bottom case 82, with respect to a power supply port of an electric vehicle or a charging device for charging the battery pack 10. Can be connected. The notch, the power supply port, and the charging device are not shown. By connecting the connector portion to the power supply port or charging device, the power supply port or charging device and the battery core pack 12 can be electrically connected via the BMU 14.

The outer shell case 84 has a square tubular shape with openings at both ends in the vertical direction. The top case 86 is a housing having an opening at the lower end, and a handle 88 that can be gripped when carrying the battery pack 10 is provided on the upper surface side.

The bottom case 82, the outer shell case 84, and the top case 86 are in a state where the bottom case 82 covers the opening on the lower end side of the outer shell case 84 and the top case 86 covers the opening on the upper end side of the outer shell case 84. Be integrated. The battery core pack 12 supported by a support frame (not shown) is housed in the internal space of the case 16 formed thereby.

In the battery pack 10 according to the present embodiment basically configured as described above, for example, the handle 88 is gripped to carry the battery pack 10 in the vicinity of the charging device, and the connector portion and the charging device are connected to each other. Therefore, the battery cell 20 can be charged. On the other hand, for example, the battery cell 20 is discharged by grasping the handle 88, carrying the battery pack 10, and mounting the battery pack 10 on the electric vehicle so that the connector portion and the power supply port are connected. Can be done.

From the above, in the battery pack 10, the lead plate 24 extends in the row direction, that is, the side 60 of the lead plate 24 in the row direction is a straight line orthogonal to the column direction. Therefore, for example, unlike the case where the side 60 in the row direction has a zigzag shape, the lead plate 24 can be obtained with high accuracy by using a simple mold, and the unused portion when the lead plate 24 is punched out from the flat plate. The ratio can be reduced to improve the material yield.

Further, in this battery pack 10, since a plurality of battery cells 20 are arranged in a zigzag in the row direction, even if the battery cells 20 are held at high density in the cell holders 22a and 22b, an external force from the radial direction of the battery cells 20 is particularly high. On the other hand, the battery cell 20 can be made hard to be crushed.

Therefore, according to the battery pack 10, it is possible to protect the battery cell 20 with a simple configuration without increasing the manufacturing cost.

In the battery pack 10 according to the above embodiment, the terminal surface 18 and the lead plate 24 are electrically connected by being welded via the welded portion 58, and the terminal surfaces 18 arranged in the row direction have the center O in the column direction. The lead plate 24 has a first terminal surface 38 arranged on one side and a second terminal surface 40 whose center O is arranged on the other side in the row direction, and the lead plate 24 has a first terminal surface 38 and a second terminal. Covers the entire covered terminal surface 68, which is one of the surfaces 40, and covers more than half and less than the entire column direction of the exposed side terminal surface 70, which is the other of the first terminal surface 38 and the second terminal surface 40. As a result, the row-direction side 60 of the lead plate 24 is arranged so as to cross the exposed terminal surface 70, the radius of the welded portion 58 is r, the diameter of the battery cell 20 is D, and the battery cells adjacent to each other in the column direction. When the distance between the outer peripheral surfaces of 20 is GP and the distance between the side 60s of the lead plates 24 adjacent in the column direction in the row direction is CL, r ≦ ((D / 2 + GP / 2) -CL) / 2. I decided to satisfy the relationship.

In this battery pack 10, by setting the radius r of the welded portion 58 as described above, even if the side 60 in the row direction of the lead plate 24 is linear, the terminal surface 18 is different from the lead plate 24 to be connected. It is possible to effectively avoid being electrically connected to different lead plates 24 and being electrically connected to each other via the welded portion 58.

In the battery pack 10 according to the above embodiment, the exposed side surface 30 is provided with an opening 36 for exposing the terminal surface 18 and an insulating portion 48 for partially covering the opening 36, which are adjacent to each other in the row direction. One side of a set of lead plates 24 is a first lead plate 72, the other side is a second lead plate 74, one side of two rows of terminal surfaces 18 adjacent in the column direction is a first row Ra, and the other side. Is the second row Rb, and the first lead plate 72 covers the entire covered terminal surface 68 of the first row Ra and half or more and less than half of the exposed terminal surface 70 of the first row Ra, and the second lead. When the plate 74 covers the entire covered terminal surface 68 of the second row Rb and more than half and less than the entire exposed side terminal surface 70 of the second row Rb, the first lead plate 72 is the second row Rb. The portion of the exposed terminal surface 70 exposed from the second lead plate 74 is opposed to the portion exposed from the second lead plate 74 via the insulating portion 48, and the second lead plate 74 is from the first lead plate 72 of the exposed terminal surface 70 of the first row Ra. It was decided to face the exposed portion via the insulating portion 48.

In this case, even if the distance between the outer peripheral surfaces of the battery cells 20 held by the cell holders 22a and 22b is reduced, the terminal surface 18 is electrically connected to the lead plate 24 which is not the connection target of the terminal surface 18 due to the insulating portion 48. It is possible to avoid being connected to the target. Therefore, it is possible to increase the density of the battery cells 20 held by the cell holders 22a and 22b while effectively suppressing the occurrence of short circuits of the battery cells 20 and the lead plate 24.

In the battery pack 10 according to the above embodiment, the insulating portion 48 is provided with an insulating wall 50 projecting between the side 60s of the first lead plate 72 and the second lead plate 74 in the row direction facing each other. Therefore, it was decided that the first lead plate 72 and the second lead plate 74 are insulated by the insulating wall 50 interposed between the sides 60 in the row direction. In this case, the insulating wall 50 extending linearly in the row direction is, for example, an insulating wall provided in a zigzag shape in the row direction so as to insulate lead plates (not shown) having zigzag-shaped sides 60 in the row direction. Compared to (not shown), it can be provided more easily. This also makes it possible to reduce the cost of the battery pack 10.

In the battery pack 10 according to the above embodiment, the slit 76 is provided in the row direction at the portion of the lead plate 24 facing the insulating portion 48. As shown in FIGS. 6 and 7, there is a step between the portion of the opening 36 covered with the insulating portion 48 and the other opening 36 adjacent in the row direction not covered by the insulating portion 48. 48a is formed. Even if the step 48a is formed in this way, the lead plate 24 can be satisfactorily aligned with the terminal surface 18 by providing the slit 76 in the lead plate 24. That is, it is possible to prevent the lead plate 24 from being stressed in the direction of being separated from the welded portion 58. As a result, the lead plate 24 and the terminal surface 18 can be satisfactorily connected via the welded portion 58.

In the battery pack 10 according to the above embodiment, the distance between the center O of the exposed side terminal surface 70 of the first row Ra and the side 60 of the first lead plate 72 in the row direction is L1, and the exposed side of the second row Rb. When the distance between the center O of the terminal surface 70 and the side 60 in the row direction of the second lead plate 74 is L2, the relationship of L1 = L2 = ((D / 2 + GP / 2) -CL) / 2 is satisfied. And said.

In this case, both the distance L1 and the distance L2 may be set to a size capable of providing a welded portion 58 having a size capable of satisfactorily welding the exposed side terminal surface 70 and the lead plate 24. can. Therefore, the exposed side terminal surface 70 of the first row Ra and the first lead plate 72 are easily welded, and the exposed side terminal surface 70 of the second row Rb and the second lead plate 74 are easily welded. Will be possible.

In the battery pack 10 according to the above embodiment, the lead plate 24 has output lead plates 62a and 62b and intermediate lead plates 64a, 64b, 64c, 64d, 64e and 64f, and the output lead plates 62a and 62b have the output lead plates 62a and 62b. , One row of terminal surfaces 18 arranged at the end of the exposed side surface 30 in the column direction are connected in parallel, and the intermediate lead plates 64a, 64b, 64c, 64d, 64e, 64f have two rows of terminal surfaces 18 in a row. It was decided to connect in series in the direction and in parallel in the row direction. In this case, a plurality of battery cells 20 held in the cell holders 22a and 22b are connected in parallel and in series to increase the output, and the output of the plurality of battery cells 20 is transmitted via the output lead plates 62a and 62b. It can be easily obtained.

In the battery pack 10 according to the above embodiment, the number of rows of the plurality of battery cells 20 held in the cell holders 22a and 22b is an odd number, and one of the set of exposed side surfaces 30 is the first exposed side surface 32 and the other. In the first exposed side surface 32, one row (R1) on one end side in the column direction is connected to the output lead plate 62a, and the remaining rows (R2 to R7) are intermediate leads. It is connected to the plates 64a, 64b, 64c, and on the second exposed side surface 34, one row (R7) on the other end side in the column direction is connected to the output lead plate 62b, and the remaining rows (R1 to R6) are in the middle. It was decided that the lead plates 64d, 64e, and 64f would be connected.

In this case, the output lead plates 62a and 62b can be arranged on each of the set of exposed side surfaces 30 of the cell holders 22a and 22b. As a result, for example, it becomes easy to arrange the exposed side surfaces 30 (second exposed side surfaces 34) of the plurality of cell holders 22a and 22b so as to face each other, and by extension, it is easy to increase the output and reduce the size of the battery pack 10. Become.

The rows of the battery cells 20 held by the cell holders 22a and 22b may be an even number. In this case, for example, output lead plates 62a and 62b are provided at both ends of the first exposed side surface 32 in the column direction, and the second exposed side surface 32 is provided. A plurality of intermediate lead plates 64d, 64e, 64f, etc. may be provided on the 34.

The battery pack 10 according to the above embodiment includes a plurality of (two) cell holders 22a and 22b, and the plurality of cell holders 22a and 22b are arranged so that the exposed side surfaces 30 (second exposed side surface 34) sides face each other. The intermediate lead plates 64d, 64e, and 64f provided on the exposed side surfaces 30 facing each other are insulated from each other via the insulating member 80, and the output lead plates 62b provided on the exposed side surfaces 30 facing each other are tabbed. It was decided that they would be electrically connected via the portion 66b. In this case, the output of the battery pack 10 can be further increased by electrically connecting the plurality of battery cells 20 held in the plurality of cell holders 22a and 22b with each other in a simple and compact configuration. The number of cell holders 22a included in the battery pack 10 may be one, or may be three or more.

In the battery pack 10 according to the above embodiment, the set of output lead plates 62b and the tab portion 66b provided on the exposed side surfaces 30 (second exposed side surfaces 34) facing each other are integrated from one metal plate. It was decided that it was formed in. In this case, the configuration of the battery pack 10 can be further simplified to further reduce the manufacturing cost. The output lead plate 62b of the cell holder 22a, the output lead plate 62b of the cell holder 22b, and the tab portion 66b may be formed separately from each other.

The present invention is not particularly limited to the above-described embodiment, and various modifications can be made without departing from the gist thereof.

For example, as shown in FIG. 9, in the lead plate 24, instead of the slit 76, a step corresponding to the thickness of the insulating portion 48 is provided between the portion facing the terminal surface 18 and the portion facing the insulating portion 48. 90 may be provided. Even in this case, since the lead plate 24 can be well aligned with the terminal surface 18 and stress in the direction of being separated from the welded portion 58 can be suppressed from being generated in the lead plate 24, the lead plate 24 and the terminal surface 18 can be suppressed. Can be satisfactorily connected via the welded portion 58.

10 ... Battery pack 12 ... Battery core pack 14 ... BMU (battery management device) 18 ... Terminal surface 20 ... Battery cells 22a, 22b ... Cell holder 24 ... Lead plate 30 ... Exposed side 32 ... First exposed side 34 ... Second exposed side 36 ... Opening 38 ... First terminal surface 40 ... Second terminal surface 48 ... Insulation part 50 ... Insulation wall 58 ... Welded part 60 ... Sides in the row direction 62a, 62b ... Output lead plates 64a, 64b, 64c, 64d, 64e , 64f ... Intermediate lead plate 66a, 66b ... Tab portion 68 ... Covered side terminal surface 70 ... Exposed side terminal surface 72 ... First lead plate 74 ... Second lead plate 76 ... Slit 80 ... Insulating member 90 ... Step

Claims (11)

A battery cell (20) that is columnar and has terminal surfaces (18) having different positive and negative ends in the axial direction, and a plurality of the battery cells in the row direction so that the terminal surfaces are arranged on the same plane. A battery pack (10) including cell holders (22a, 22b) that hold the cells side by side in the column direction, and a plurality of lead plates (24) that electrically connect the terminal surfaces arranged in the row direction at least. hand,
The cell holder has a set of exposed side surfaces (30) provided with openings (36) for exposing the terminal surfaces on both axial directions of the plurality of battery cells from the cell holder, respectively, and in the row direction. The centers (O) of the adjacent terminal surfaces are held so as to be alternately arranged on one side and the other side in the row direction.
The plurality of terminal surfaces arranged on the exposed side surfaces have the same positive and negative positive and negative sides of the terminal surfaces adjacent to each other in the row direction, and the positive and negative sides of the terminal surfaces adjacent to each other in the column direction are different.
A battery pack in which the plurality of lead plates are arranged so as to be spaced apart from each other in the column direction with respect to the exposed side surface and extend in the row direction. In the battery pack according to claim 1,
The terminal surface and the lead plate are electrically connected by being welded via a welded portion (58).
The terminal surfaces arranged in the row direction include a first terminal surface (38) whose center is arranged on one side in the column direction and a second terminal surface (38) whose center is arranged on the other side in the column direction. 40) and
The lead plate covers the entire covered terminal surface (68), which is either one of the first terminal surface and the second terminal surface, and is the other of the first terminal surface and the second terminal surface. By covering more than half of the exposed side terminal surface (70) in the column direction and less than the whole, the side (60) in the row direction of the lead plate is arranged so as to cross the exposed side terminal surface.
The radius of the welded portion is r, the diameter of the battery cell is D, the distance between the outer peripheral surfaces of the battery cells adjacent to the column direction is GP, and the row direction of the lead plate adjacent to the column direction is A battery pack that satisfies the relationship of r≤((D / 2 + GP / 2) -CL) / 2, where CL is the distance between the sides. In the battery pack according to claim 2,
The exposed side surface is provided with an opening (36) for exposing the terminal surface and an insulating portion (48) for partially covering the opening.
One side of the set of lead plates adjacent to each other in the column direction is a first lead plate (72), and the other side is a second lead plate (74). One side is the first row (Ra), the other side is the second row (Rb), and the first lead plate is the entire covered terminal surface of the first row and the exposure of the first row. Covering more than half and less than the entire side terminal surface, the second lead plate covers the entire covered side terminal surface in the second row and more than half and less than the entire exposed side terminal surface in the second row. When covering
The first lead plate faces a portion of the exposed terminal surface of the second row exposed from the second lead plate via the insulating portion.
The second lead plate is a battery pack that faces a portion of the exposed terminal surface of the first row exposed from the first lead plate via the insulating portion. In the battery pack according to claim 3,
The insulating portion is provided with an insulating wall (50) that projects toward the sides of the lead plates adjacent to each other in the row direction, and is provided by the insulating wall that is interposed between the sides in the row direction. , A battery pack in which the lead plates adjacent to each other are insulated from each other. In the battery pack according to claim 3 or 4.
A battery pack in which slits (76) are provided in the row direction in a portion of the lead plate facing the insulating portion. In the battery pack according to claim 3 or 4.
A battery pack in which the lead plate is provided with a step (90) according to the thickness of the insulating portion between a portion facing the terminal surface and a portion facing the insulating portion. In the battery pack according to any one of claims 3 to 6.
The distance between the center of the exposed terminal surface of the first row and the side of the first lead plate in the row direction is L1, and the center of the exposed terminal surface of the second row and the second lead A battery pack that satisfies the relationship of L1 = L2 = ((D / 2 + GP / 2) -CL) / 2, where L2 is the distance from the side of the board in the row direction. In the battery pack according to any one of claims 1 to 7.
The lead plate has an output lead plate (62a, 62b) and an intermediate lead plate (64a, 64b, 64c, 64d, 64e, 64f).
The output lead plate connects in parallel one row of the terminal surfaces arranged at the end of the exposed side surface in the column direction.
The intermediate lead plate is a battery pack in which two rows of terminal surfaces are connected in series in the column direction and in parallel in the row direction. In the battery pack according to claim 8,
The number of rows of the plurality of battery cells held in the cell holder is odd.
When one of the set of exposed side surfaces is a first exposed side surface (32) and the other is a second exposed side surface (34),
On the first exposed side surface, one row on one end side in the column direction is connected to the output lead plate, and the remaining rows are connected to the intermediate lead plate.
On the second exposed side surface, a battery pack in which one row on the other end side in the column direction is connected to the output lead plate, and the remaining rows are connected to the intermediate lead plate. In the battery pack according to claim 8 or 9.
With a plurality of the cell holders
The plurality of cell holders are arranged so that the exposed side surfaces of the cell holders face each other.
The intermediate lead plates provided on the exposed side surfaces facing each other are insulated from each other via an insulating member (80).
A battery pack in which the output lead plates provided on the exposed side surfaces facing each other are electrically connected to each other via a tab portion (66b). In the battery pack according to claim 10,
A battery pack in which a set of output lead plates provided on the exposed side surfaces facing each other and the tab portion are integrally formed from a single metal plate.

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