JP6065368B2 - Assembled battery - Google Patents

Description

  The present invention relates to an assembled battery in which terminals of a plurality of single cells are connected by a bus bar.

  Conventionally, a battery mounted on an electric vehicle such as an electric vehicle uses an assembled battery configured by connecting a plurality of single cells in series or in parallel in order to satisfy electric power necessary for driving the battery. The assembled battery has a configuration in which a plurality of unit cells are arranged and terminals of the unit cells adjacent to each other are connected by a bus bar (connection rod).

  Here, as shown in Patent Document 1, the unit cell has a positive electrode terminal and a negative electrode terminal protruding from the upper surface of a substantially rectangular parallelepiped battery casing, and the positive electrode terminal and the negative electrode terminal have the same shape as each other. In addition, the shape is symmetrical with respect to the center plane of the battery casing.

  However, when assembling an assembled battery by arranging a plurality of single cells, when some of the single cells are arranged in the reverse direction, the positive terminal and the negative terminal are located with respect to the center surface of the battery case. Due to the symmetrical shape, there is a problem that it is difficult to understand that they are arranged in the opposite direction. In addition, there is a problem that the bus bar can be connected as usual between terminals arranged in error. For this reason, when assembling the assembled battery, there is a problem that the positive electrode terminal and the negative electrode terminal of the unit cell are connected in reverse.

JP 2010-272324 A

  Therefore, the present invention has been made to solve the above-mentioned problems all at once, and its main intended problem is to structurally prevent such erroneous connection when connecting a plurality of single cells with a bus bar. To do.

  That is, the assembled battery according to the present invention is an assembled battery configured by electrically connecting terminals of a plurality of single cells having a positive electrode terminal and a negative electrode terminal protruding from a battery housing using a bus bar, The outer shape of the positive electrode terminal and the outer shape of the negative electrode terminal are different from each other, and the bus bar has a positive terminal fitting portion corresponding to the outer shape of the positive electrode terminal and a negative electrode terminal fitting corresponding to the outer shape of the negative electrode terminal. It has the part.

  The positive terminal has a generally rectangular shape in plan view with which the positive terminal fitting portion is fitted, and the negative terminal has a generally rectangular shape in plan view with which the negative terminal fitting portion is fitted. Preferably, the width of the positive electrode terminal and the width of the negative electrode terminal are different from each other.

  Of the positive-electrode-side insulating frame provided around the positive-electrode terminal or the positive-electrode terminal, the higher positive-side maximum height and the higher of the negative-electrode-side insulating frame provided around the negative-electrode terminal or the negative-electrode terminal The negative electrode side maximum height is different from each other, the positive electrode terminal fitting portion has a shape corresponding to the positive electrode side maximum height, and the negative electrode terminal fitting portion has a shape corresponding to the negative electrode side maximum height. It is desirable to have.

  Among the positive electrode side insulating frame provided around the positive electrode terminal or the negative electrode side insulating frame provided around the negative electrode terminal, the height of the insulating frame provided around the small terminal, and the other Preferably, the positive electrode terminal fitting portion and the negative electrode terminal fitting portion have shapes corresponding to the heights of the respective insulating frames.

  The cross-sectional area / electric resistivity value of the positive electrode terminal and the cross-sectional area / electric resistivity value of the negative electrode terminal are preferably substantially the same.

  It is desirable that the positive electrode terminal is aluminum, the negative electrode terminal is copper, and a cross-sectional area of the positive electrode terminal is larger than a cross-sectional area of the negative electrode terminal.

  According to the present invention configured as described above, the outer shape of the positive electrode terminal and the outer shape of the negative electrode terminal are made different from each other, and the bus bar has a positive electrode terminal fitting portion corresponding to the outer shape of the positive electrode terminal and the outer shape of the negative electrode terminal. Since it has the corresponding negative electrode terminal fitting part, when connecting a several cell with a bus bar, those misconnection can be prevented structurally.

The perspective view which shows the assembled battery in this embodiment. The perspective view which shows the structure of the cell of the same embodiment. The top view and side view which show the structure of the cell of the embodiment. The perspective view and side view which show the structure of the bus-bar of the embodiment. The perspective view and schematic diagram which show the misconnection when negative electrode terminals adjoin in the same embodiment. The perspective view and schematic diagram which show the misconnection when positive electrode terminals adjoin in the same embodiment. The perspective view and schematic diagram which show the case where it connects normally in the same embodiment.

  Hereinafter, an embodiment of an assembled battery according to the present invention will be described with reference to the drawings.

  The assembled battery 100 according to the present embodiment is mounted on an electric vehicle such as a hybrid electric vehicle, for example. As shown in FIG. 1, for example, a non-aqueous electrolyte secondary battery (hereinafter referred to as “lithium ion battery”). A plurality of single cells 2 ") are arranged, and terminals 5 and 6 of adjacent single cells 2 are connected by a bus bar 3 (connection rod).

  The unit cell 2 is a rectangular battery, and as shown in FIGS. 1 to 3, as a whole, a flat battery case 4 having a substantially rectangular parallelepiped shape, a positive electrode terminal 5 provided so as to protrude from the upper surface of the battery case 4, and And a negative electrode terminal 6. The battery housing 4 includes a metal housing body 41 having a rectangular opening in plan view, and a flat housing lid 42 that closes the opening of the housing body 41. When arranging a plurality of single cells 2, the battery housings 4 are arranged in the short direction (thickness direction).

  Further, in the battery housing 4, a power generation element (not shown) configured by winding a foil-like positive electrode plate coated with a positive electrode active material and a foil-like negative electrode plate coated with a negative electrode active material with a separator interposed therebetween. And a positive electrode current collector (not shown) welded to the foil-like positive electrode plate of the power generation element on one side surface of the power generation element, and a foil current negative electrode plate of the power generation element to the other side surface of the power generation element A negative electrode current collector (not shown) is accommodated.

  The positive electrode terminal 5 provided so as to protrude from the upper surface of the battery housing 4 is electrically connected to the positive electrode current collector housed in the battery housing 4, and the housing lid portion 42 in the battery housing 4. A positive plate terminal portion 51 having a substantially rectangular shape in plan view, and a positive screw terminal portion 52 extending upward from the positive plate terminal portion 51. A positive electrode side insulating frame 53 is provided around the positive electrode plate terminal portion 51. The positive electrode side insulating frame 53 covers the side surfaces except the upper surface of the positive electrode plate terminal portion 51.

  The negative electrode terminal 6 provided so as to protrude from the upper surface of the battery housing 4 is electrically connected to the negative electrode current collector housed in the battery housing 4, and the housing lid portion 42 in the battery housing 4. A negative plate terminal portion 61 having a substantially rectangular shape in plan view, and a negative screw terminal portion 62 extending upward from the negative plate terminal portion 61. In addition, a negative electrode side insulating frame 63 is provided around the negative electrode plate terminal portion 61. The negative electrode side insulating frame 63 covers the side surfaces except the upper surface of the negative electrode plate terminal portion 61.

  Further, the height of the upper surface of the positive electrode plate terminal portion 51 and the upper surface of the negative electrode plate terminal portion 61 are substantially the same, that is, the upper surface of the positive electrode plate terminal portion 51 and the upper surface of the negative electrode plate terminal portion 61 are substantially on the same horizontal plane. Is located. Further, the positive electrode screw terminal portion 52 of the positive electrode terminal 5 and the negative electrode screw terminal portion 62 of the negative electrode terminal 6 have substantially the same shape, and are provided at symmetrical positions with respect to the center plane of the battery housing 4 (see FIG. 3). ).

  Thus, the positive electrode terminal 5 and the negative electrode terminal 6 of the present embodiment are configured such that the width of the positive electrode plate terminal portion 51 is larger than the width of the negative electrode plate terminal portion 61 and the positive electrode plate terminal portion 51 is formed of aluminum. The negative electrode plate terminal portion 61 is made of copper. In the present embodiment, the longitudinal length of the positive electrode plate terminal portion 51 and the longitudinal length of the negative electrode plate terminal portion 61 are substantially the same. Here, the length in the longitudinal direction of the plate terminal portion is the length in the direction along the longitudinal direction of the battery housing 4. In the present embodiment, the thicknesses of the plate terminal portions 51 and 61 are substantially the same, and the cross-sectional areas of the plate terminal portions 51 and 61 are also different due to the different widths of the plate terminal portions 51 and 61.

  The width of the positive electrode plate terminal portion 51 and the width of the negative electrode plate terminal portion 61 are the ratio of the cross-sectional area of the positive electrode plate terminal portion 51 and the electrical resistivity of the material (aluminum) of the positive electrode plate terminal portion 51 (cross-sectional area / The electrical resistivity) and the ratio of the cross-sectional area of the negative electrode plate terminal portion 61 and the electrical resistivity of the material (copper) of the negative electrode plate terminal portion 61 (cross-sectional area / electric resistivity) are determined to be substantially the same. It is done. Thus, by making the cross-sectional area / electric resistivity value of the positive electrode plate terminal portion 51 and the cross-sectional area / electric resistivity value of the negative electrode plate terminal portion 61 the same, the positive electrode plate terminal portion 51 and the negative electrode plate terminal The amount of heat generated in the part 61 can be made uniform.

  As shown in FIG. 4, the bus bar (connection rod) 3 is in contact with the upper surface of the positive electrode plate terminal portion 51 and the upper surface of the negative electrode plate terminal portion 61 to form a flat connection conductor 31. And an insulating frame 32 that covers the side surfaces of the connection conductor 31 excluding the upper surface and the lower surface.

  The connection conductor 31 is made of metal having a substantially rectangular shape in plan view, and has two through holes 31a and 31b through which the positive electrode screw terminal portion 52 and the negative electrode screw terminal portion 62 of the unit cell 2 arranged adjacent to each other are inserted. It is provided at both ends. Then, the positive screw terminal 52 or the negative screw terminal extending to the upper surface of the connecting conductor 31 in a state where the positive screw terminal 52 or the negative screw terminal 62 is inserted into the through holes 31a and 31b of the connection conductor 31. When the nut member 7 is screwed to the portion 62, the lower surface of the connection conductor 31 is pressed into contact with the upper surface of the positive electrode plate terminal portion 51 or the upper surface of the negative electrode plate terminal portion 61.

  The insulating frame 32 includes a positive electrode terminal fitting portion 32 a corresponding to the outer shape of the positive electrode plate terminal portion 51 in the positive electrode terminal 5 and a negative electrode terminal fitting portion 32 b corresponding to the outer shape of the negative electrode plate terminal portion 61 in the negative electrode terminal 6. And have.

  Specifically, the insulating frame 32 has a lower side wall portion 321 extending below the lower surface of the connection conductor 31 in a state of surrounding the connection conductor 31, and a positive terminal fitting portion is provided on the lower side wall portion 321. 32a and a negative terminal fitting portion 32b are formed. In other words, in the present embodiment, the connection conductor 31 is processed in the lower side wall portion 321 of the insulating frame 32 without processing the flat plate shape, so that the positive terminal fitting portion 32a and the negative terminal fitting portion 32b are processed. Forming and reducing manufacturing costs.

  The positive electrode terminal fitting portion 32 a is a concave portion having a shape corresponding to the outer shape of the positive electrode plate terminal portion 51 in a side view, and the concave shape is a dimension in the width direction of the positive electrode plate terminal portion 51 and the positive electrode side insulating frame 53. And a recess having a size substantially the same as or slightly larger. Further, the depth of the concave portion may be any depth as long as the lower surface of the connection conductor 31 is in contact with the upper surface of the positive electrode plate terminal portion 51. When the positive electrode terminal fitting portion 32a is fitted to the positive electrode plate terminal portion 51 or fitted with some play, the upper surface of the positive electrode plate terminal portion 51 and the lower surface of the connection conductor 31 come into contact with each other.

  The negative electrode terminal fitting portion 32 b is a concave portion having a shape corresponding to the outer shape of the negative electrode plate terminal portion 61 in a side view, and the concave shape is a dimension in the width direction of the negative electrode plate terminal portion 61 and the negative electrode side insulating frame 63. And a recess having a size substantially the same as or slightly larger. That is, the width of the concave portion that is the negative electrode terminal fitting portion 32b is formed to be smaller than the width of the concave portion that is the positive electrode terminal fitting portion 32a. Further, the depth of the concave portion may be any depth as long as the lower surface of the connection conductor 31 is in contact with the upper surface of the negative electrode plate terminal portion 61. When the negative electrode terminal fitting portion 32b is fitted to the negative electrode plate terminal portion 61 or fitted with some play, the upper surface of the negative electrode plate terminal portion 61 and the lower surface of the connection conductor 31 are in contact with each other.

  Furthermore, in the present embodiment, a protrusion accommodating portion 32c that is recessed corresponding to the protrusion 631 (see FIG. 3) formed on the upper surface of the negative electrode side insulating frame 63 is formed on the bottom surface of the negative electrode terminal fitting portion 32b. Has been. As described above, the concavo-convex structure including the protrusion 631 formed on the negative electrode-side insulating frame 63 and the protrusion accommodating portion 32c formed on the negative electrode terminal fitting portion 32b causes an error when the negative electrodes 6 are arranged adjacent to each other. An incorrect connection prevention structure for preventing connection is configured. The protrusion 631 of the present embodiment is formed on the inner wall of the negative electrode side insulating frame 63 (see FIG. 3), and the height of the negative electrode side insulating frame 63 (maximum negative electrode side) is determined by the protrusion 631. (Height) is higher than the height of the positive electrode side insulating frame 53 (maximum height on the positive electrode side). Further, the protrusion accommodating portion 32c formed in the negative electrode terminal fitting portion 32b may not completely correspond to the shape of the protruding portion 631, and as shown in FIG. What is necessary is just to make the depth of the terminal fitting part 32b deep, and to respond | correspond.

  Next, in the assembled battery configured as described above, (1) misplacement in which the negative electrode terminals 6 of the two unit cells 2 are adjacent to each other, (2) misplacement in which the positive electrode terminals 5 are adjacent to each other, and (3) positive electrode terminal The positional relationship between the terminals 5 and 6 and the bus bar 3 in a normal arrangement in which the 5 and the negative electrode terminal 6 are adjacent to each other will be described with reference to FIGS.

(1) In the case of misplacement in which the negative electrode terminals 6 of two unit cells 2 are adjacent to each other, as shown in FIG. 5, when the negative electrode terminals 6 are adjacent to each other, when the bus bar 3 is connected to the two negative electrode terminals 6, Before the normally arranged negative electrode plate terminal portion 61 is fitted into the negative electrode terminal fitting portion 32b of the bus bar 3, the protrusion 631 of the negative electrode plate terminal portion 61 that is mistakenly arranged is fitted into the positive electrode terminal fitting of the bus bar 3. It contacts the bottom surface of the joint portion 32a. That is, before the protrusion 631 of the negative plate terminal portion 61 that is normally arranged is fitted to the protrusion accommodating portion 32c formed in the negative electrode terminal fitting portion 32b, the negative plate terminal portion 61 that is mistakenly arranged is fitted. The protrusion 631 interferes with the positive terminal fitting portion 32a. For this reason, it turns out that it is misplacement from the bus bar 3 wobbling and being arranged diagonally.

  When the protruding portion 631 is not formed, the negative terminal 6 misplaced enters the positive terminal fitting portion 32a of the bus bar 3, and the normal terminal fitting portion 32b of the bus bar 3 is normal. The arranged negative electrode terminal 6 enters. That is, when the negative electrode terminals 6 are adjacent to each other, there is a problem that it is difficult to determine whether the connection is incorrect. In such a case, by providing the protruding portion 631 on the negative electrode plate terminal portion 61 side, it can be structurally understood that a part of the unit cell 2 is erroneously arranged in the reverse direction as described above.

(2) When the positive terminals 5 of the two unit cells 2 are adjacent to each other, as shown in FIG. 6, when the positive terminals 5 are adjacent to each other, when the bus bar 3 is connected to the two positive terminals 5, Before the positive plate terminal portion 51 that is normally arranged in the positive electrode terminal fitting portion 32 a of the bus bar 3 is fitted, the positive plate terminal portion 51 that is mistakenly arranged is larger than the width dimension of the positive plate terminal portion 51. It does not fit into the small negative terminal fitting part 32b. For this reason, it turns out that it is misplacement from the bus bar 3 wobbling and being arranged diagonally.

(3) When the positive electrode terminal 5 and the negative electrode terminal 6 of the two unit cells 2 are correctly adjacent to each other, as shown in FIG. 7, when the positive electrode terminal 5 and the negative electrode terminal 6 are adjacent to each other, When the bus bar 3 is connected to the negative terminal 6, the positive plate terminal part 51 is fitted to the positive terminal fitting part 32 a of the bus bar 3, and the negative plate terminal part 61 is fitted to the negative terminal fitting part 32 b of the bus bar 3. The protrusion 631 provided on the negative electrode side insulating frame 63 is fitted into the protrusion accommodating part 32c provided on the negative electrode terminal fitting part 32b. When correctly fitted in this way, the height of the upper surface of the positive electrode plate terminal portion 51 and the upper surface of the negative electrode plate terminal portion 61 are the same, so that the bus bar 3 is in a posture along the horizontal direction. And after each fitting part 32a, 32b fits to each plate terminal part 51,61, the nut member 7 is screwed together in each screw terminal part 52,62, and the bus-bar 3 is pressed to plate terminal part 51,61. The assembled battery 100 is configured by being fixed (see FIG. 1).

  According to the battery 100 according to this embodiment configured as described above, the outer shape of the positive electrode terminal 5 and the outer shape of the negative electrode terminal 6 are different from each other, and the bus bar 3 is fitted to the positive electrode terminal corresponding to the outer shape of the positive electrode terminal 5. Since it has the negative electrode terminal fitting part 32b corresponding to the external shape of the joint part 32a and the negative electrode terminal 6, when some of the single cells 2 are mistakenly arranged in the reverse direction, the single cells 2 arranged incorrectly The positive electrode terminal 5 or the negative electrode terminal 6 and the positive electrode terminal fitting portion 32a or the negative electrode terminal fitting portion 32b of the bus bar 3 are not fitted. As a result, it is structurally known that a part of the unit cell 2 is mistakenly arranged in the reverse direction, so that the unit cell 2 in the assembled battery 100 can be prevented from being erroneously connected.

  Further, the positive electrode terminal 5 has a substantially rectangular shape in plan view, the negative electrode terminal 6 has a substantially rectangular shape in plan view, and the width of the positive electrode terminal 5 and the width of the negative electrode terminal 6 are different from each other. The configurations of the positive electrode terminal 5 and the negative electrode terminal 6 can be simplified, and the configurations of the positive electrode terminal fitting portion 32a and the negative electrode terminal fitting portion 32b that are fitted to the positive electrode plate terminal portion 51 and the negative electrode plate terminal portion 61 are provided. Can also be simplified. That is, the positive terminal fitting portion 32a and the negative terminal fitting portion 32b need only be concave. In addition, since the width of the positive electrode plate terminal portion 51 and the width of the negative electrode plate terminal portion 61 need only be different, it is not necessary to change the structure of other battery components, and the conventional battery components can be used widely. .

  Further, a protrusion 631 is formed on the upper surface of the negative electrode side insulating frame 63 so that the negative electrode side maximum height of the negative electrode side insulating frame 63 is made higher than the positive electrode side maximum height of the positive electrode side insulating frame 53. Since the protrusion accommodating portion 32c corresponding to the protruding portion 631 is formed in the terminal fitting portion 32b, the bus bar 3 is adjacent in both the misplacement in which the positive terminals 5 are adjacent to each other and the misplacement in which the negative electrode terminal 6 is adjacent. Since the terminals are not fitted to each other, erroneous connection of the unit cells 2 in the assembled battery 100 can be further prevented. Here, since the protrusions 631 are provided on the negative electrode-side insulating frame 63 provided around the negative electrode plate terminal portion 61 to make the heights of the insulating frames different, the heights of the terminals are made different. In addition, the design and manufacture are facilitated, and the design of the positive terminal 5 and the negative terminal 6 and the design of the screw terminal portions 52 and 62 can be made as common as possible.

  Further, the positive electrode plate terminal portion 51 is formed of aluminum, the negative electrode plate terminal portion 61 is formed of copper, and the cross sectional area / electric resistivity of the positive electrode plate terminal portion 51 and the cross sectional area / electric resistivity of the negative electrode plate terminal portion 61. Since the width of the positive electrode plate terminal portion 51 and the width of the negative electrode plate terminal portion 61 are made different from each other, the heat generation amount of the positive electrode terminal and the negative electrode terminal is made uniform and It is possible to prevent erroneous connection all at once.

  Furthermore, by making the positive electrode plate terminal portion of the positive electrode terminal made of aluminum, the material cost is lower than that of copper, and a structure using a lot of light aluminum is used to reduce the weight of the unit cell and the assembled battery while reducing the cost. it can.

  The present invention is not limited to the above embodiment.

  For example, in the above embodiment, the positive electrode plate terminal portion 51 is configured to have a width larger than that of the negative electrode plate terminal portion 61. From the viewpoint of preventing erroneous connection, the negative electrode plate terminal portion 61 has a width that is equal to the positive electrode plate. It may be configured to be larger than the width of the terminal portion 51. In this case, the positive electrode-side insulating frame 53 is provided with the protrusion 631 and the positive electrode terminal fitting portion 32a is formed with the protrusion accommodating portion, so that the positive terminals 5 of the two unit cells 2 are adjacent to each other. It can be easily judged.

  Moreover, in the said embodiment, in order to simplify the structure of the plate terminal parts 51 and 52 and the bus bar 3, and to reduce manufacturing cost, it is set as the structure which forms a fitting part in the insulating frame 32 of the bus bar 3, A fitting portion may be formed in the connection conductor 31 of the bus bar 3. Further, by providing the protrusion 631 on the plate terminal portion, the maximum positive electrode-side height and the negative electrode-side maximum height may be made different from each other, and a protrusion accommodating portion corresponding to the protrusion 631 may be formed on the connection conductor 31.

  Furthermore, in the embodiment, in addition to the configuration in which the width dimensions of the plate terminal portions 51 and 52 are different from each other, when the terminals 5 and 6 are misplaced, the fitting portions 32a and 32b of the bus bar 3 5 and 6, for example, a configuration in which the positive electrode terminal 5 and the negative electrode terminal 6 have different sizes, a configuration in which the plate terminal portions 51 and 61 have different heights, a positive electrode-side insulating frame 53, and Various configurations, such as making the shape of the negative electrode side insulating frame 63 different, can be adopted. Each terminal may not have the screw terminal portions 52 and 62.

  In addition, the positive terminal fitting part 32a and the negative terminal fitting part 32b are formed corresponding to the outer shapes of the positive terminal 5 and the negative terminal 6, respectively. It is sufficient that the terminals misplaced in 32b are formed in a shape that does not fit, and even if the fitting portion is not the same size as the size of the terminals arranged normally, it fits in the terminals arranged normally with a gap. May be.

  In addition, it goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 100 ... Battery assembly 2 ... Single cell 3 ... Bus bar 32a ... Positive electrode terminal fitting part 32b ... Negative electrode terminal fitting part 4 ... Battery housing 5 ... Positive electrode terminal 51- .... Positive electrode plate terminal part 53 ... Positive electrode side insulating frame 6 ... Negative electrode terminal 61 ... Negative electrode plate terminal part 63 ... Negative electrode side insulating frame 631 ... Projection part

Claims (4)

A battery assembly configured by electrically connecting terminals of a plurality of single cells having a positive electrode terminal and a negative electrode terminal protruding from a battery housing using a bus bar,
While the outer shape of the positive terminal and the outer shape of the negative terminal are different from each other,
The bus bar has a positive terminal fitting portion corresponding to the outer shape of the positive terminal and a negative terminal fitting portion corresponding to the outer shape of the negative terminal,
Of the positive-electrode-side insulating frame provided around the positive-electrode terminal or the positive-electrode terminal, the higher positive-side maximum height and the higher of the negative-electrode-side insulating frame provided around the negative-electrode terminal or the negative-electrode terminal Different from the negative electrode side maximum height,
The positive electrode terminal fitting portion has a shape corresponding to the positive electrode side maximum height, the negative electrode terminal fitting portion has a shape corresponding to the negative electrode side maximum height,
Among the positive electrode side insulating frame provided around the positive electrode terminal or the negative electrode side insulating frame provided around the negative electrode terminal, the height of the insulating frame provided around the small terminal, and the other The height of the insulation frame is different from each other,
The assembled battery, wherein the positive terminal fitting portion and the negative terminal fitting portion have shapes corresponding to the heights of the respective insulating frames. A battery assembly configured by electrically connecting terminals of a plurality of single cells having a positive electrode terminal and a negative electrode terminal protruding from a battery housing using a bus bar,
While the outer shape of the positive terminal and the outer shape of the negative terminal are different from each other,
The bus bar includes a connection conductor that electrically connects the positive electrode terminal and the negative electrode terminal, and an insulating frame that covers a side surface of the connection conductor;
The insulating frame has a positive terminal fitting portion corresponding to the outer shape of the positive terminal and a negative terminal fitting portion corresponding to the outer shape of the negative terminal,
Of the positive-electrode-side insulating frame provided around the positive-electrode terminal or the positive-electrode terminal, the higher positive-side maximum height and the higher of the negative-electrode-side insulating frame provided around the negative-electrode terminal or the negative-electrode terminal Different from the negative electrode side maximum height,
The assembled battery, wherein the positive electrode terminal fitting portion has a shape corresponding to the positive electrode side maximum height, and the negative electrode terminal fitting portion has a shape corresponding to the negative electrode side maximum height. 3. The assembled battery according to claim 1, wherein the cross-sectional area / electric resistivity value of the positive electrode terminal and the cross-sectional area / electric resistivity value of the negative electrode terminal are the same. The positive terminal is aluminum, the negative terminal is copper,
The assembled battery according to any one of claims 1 to 3 , wherein a cross-sectional area of the positive electrode terminal is larger than a cross-sectional area of the negative electrode terminal.