JP2007109550A - Battery and battery pack - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a battery and a battery pack decreasing a space for connecting a terminal and preventing a large drop in energy density or an input and output energy density, by connecting with the minimum connecting member by optimizing a terminal fitting position of the battery when assembling the battery pack. <P>SOLUTION: The battery 10 is equipped with an outer packaging 15 covering a power generation element 10a, a positive terminal 16 projecting from one side surface 21 of the outer packaging 15, and a negative terminal 17 projecting from a side surface 22 on the opposite side to the side surface 21. The positive terminal 16 and the negative terminal 17 have a plane plate shape, and are fit to the power generation element 10a so that the width direction of each of the terminals 16, 17 is almost parallel to the thickness direction of the outer packaging. The positive terminal 15 and the negative terminal 16 are projected to shift to the width direction of the outer packaging 15. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a battery and an assembled battery formed by combining a plurality of these batteries, and more particularly, to a battery and an assembled battery that form a combined battery by combining a plurality of the batteries.

In recent years, electronic devices such as video cameras and notebook computers have been miniaturized, and compact cylindrical batteries and prismatic batteries are known as batteries used in these electronic devices.
As this type of battery, for example, a battery in which a separator is disposed between a positive electrode and a negative electrode is wound and the wound laminate is stored in a cylindrical container or a rectangular container, and the positive electrode and the positive terminal are connected. In some cases, the positive electrode terminal protrudes from the container to the outside, the negative electrode and the negative electrode terminal are connected, and the negative electrode terminal protrudes from the container to the outside (see, for example, Patent Documents 1 and 2).
JP 2002-252036 A JP 2002-298922 A

  These cylindrical batteries and prismatic batteries are often used as assembled batteries by modularizing and combining a plurality of them in a state where they are connected in series or in parallel in order to ensure the voltage required for electronic equipment. For example, when a plurality of cylindrical batteries are connected, the plurality of cylindrical batteries are arranged on the same axis, and adjacent positive and negative terminals are connected using a connecting member. In addition, when a plurality of prismatic batteries are connected, adjacent positive and negative terminals are connected using a connecting member, as in the case of a cylindrical battery.

  By the way, in order to connect the positive electrode terminal and negative electrode terminal of an adjacent battery, a current collection connection space and a connection member are required.

  Here, when the current collecting connection space is increased, the size of the entire assembled battery is increased, the output efficiency with respect to the size of the battery is decreased, and the energy density and the output density are decreased.

  In addition, considering the manufacturing cost, a simple connection member is preferable. However, depending on the battery terminal shape or current collection connection space size, the connection member may have a complicated structure (from multiple parts). Need to be used). Further, when the structure of the connecting component is complicated, the current collecting resistance is increased due to contact resistance or the like, and the output of the battery is lowered.

For example, in a flat battery provided with flat-shaped terminals, if the width direction of the terminals is parallel to the flat surface, the flat battery terminals stacked in the thickness direction can be bent and connected directly, so a connecting member is separately provided. There is no need to prepare. However, in order to bend a flat terminal, the terminal must be thin to some extent. However, in a battery that requires a large input / output energy density, it is necessary to secure a certain cross-sectional area of the terminal, so that the terminal cannot be thin enough to bend. For example, in a battery having a charging depth (SOC) 50% and an input / output energy density at 25 ° C. of 2000 Wh / kg or more, for example, the temperature rise of the terminal when 200 A continuous energization is performed is not too large. In this case, the cross-sectional area of the terminal must be 10 mm ² or more, and it is not possible to use a terminal that is thin enough to bend due to the strength problem of welding the terminal. That is, in a battery that requires a large input / output energy density, if the width direction of the terminal is parallel to the flat surface in a flat battery provided with flat plate-shaped terminals, the terminals of the flat batteries stacked in the thickness direction are connected to each other. In order to connect, it was necessary to prepare many connection parts or complicated connection parts.

  The present invention has been made in view of the above circumstances, and when forming an assembled battery, by connecting terminals with a simple configuration without using a complicated connection member, the energy density and input / output energy density are greatly reduced. It is an object to provide a battery and a battery pack having no battery.

  The battery of the present invention includes an exterior body that covers a power generation element, a positive electrode terminal that projects from one side surface of the exterior body, and a negative electrode terminal that projects to the opposite side of the one side surface, the positive electrode terminal and the negative electrode terminal Are each attached to the power generation element such that the width direction of each terminal is substantially parallel to the thickness direction of the exterior body, and the positive electrode terminal and the negative electrode terminal are respectively connected to the exterior body. It is characterized by protruding in the width direction.

  Therefore, according to the battery of the present invention, when a plurality of batteries are connected and assembled as an assembled battery, the two batteries are shifted in the width direction and stacked in the thickness direction, and the terminal protrudes from one side of one battery. And a terminal protruding from the other side surface of the other battery can be connected so as to overlap each other.

  In addition, according to the battery of the present invention, since the terminals are attached to the power generation element so that the width direction of each terminal is substantially parallel to the thickness direction of the exterior body, the surfaces of the two terminals to be connected are flush with each other. Can be arranged. Therefore, if a connection member having a simple flat plate shape is used, the two terminals can be easily connected without providing a large connection space. Therefore, the space required for connecting the terminals can be kept small, and an assembled battery is obtained in which the energy density and the input / output energy density are not greatly reduced from the unit cell.

  The battery according to claim 1, wherein the positive electrode terminal and the negative electrode terminal protrude from the center in the width direction of the exterior body while being shifted from each other in the reverse direction at equal intervals.

According to the present invention, the positive electrode terminal and the negative electrode terminal are arranged at equal intervals from the center in the width direction, and are protruded in the opposite direction. The positive electrode terminal and the negative electrode terminal or the positive electrode terminals and the negative electrode terminals can be overlapped with each other.
Thereby, it becomes possible to arrange a some battery in the state without a substantially clearance gap, and a some battery can be collected still more compactly.

  The assembled battery of the present invention includes a plurality of the above-described batteries, and each battery is alternately stacked so as to have a plurality of stages in the thickness direction by shifting in the width direction. And the other terminal of the one battery and the battery adjacent to the thickness direction and the terminal of the battery adjacent to the opposite terminal.

  Thus, according to the assembled battery of the present invention, a plurality of batteries are stacked so as to shift in the width direction and to have a plurality of stages in the thickness direction. Thereby, it becomes possible to arrange a plurality of batteries densely without a gap, and it is possible to collect a plurality of batteries in a more compact manner.

  Further, the assembled battery of the present invention is a battery terminal adjacent to the one terminal of the one battery in the thickness direction and the battery terminal adjacent to the other terminal of the one battery in the thickness direction. The battery terminals are stacked so as to be arranged in a straight line in the thickness direction.

  Thus, according to the assembled battery of the present invention, terminals of adjacent batteries are arranged in a straight line in the thickness direction. Therefore, a large overlapping margin between terminals can be secured, and a decrease in energy density and input / output energy density can be suppressed.

  The battery and the assembled battery of the present invention minimize the space where the connecting member and the connecting member are attached when the batteries are assembled into an assembled battery, and do not greatly reduce the energy density and the input / output energy density from the unit cell. It can be.

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

  FIG. 1 is a diagram showing a battery according to the present embodiment, where (a) is a perspective view of the battery, and (b) is a top view of the battery. FIG. 2 is a top view of the assembled battery of the present embodiment. FIG. 3 is a side view of the assembled battery of the present embodiment.

  As shown in FIG. 1, the battery 10 is formed by winding a separator 13 between a positive electrode 11 and a negative electrode 12 into a flat shape to form a pole group 14, and the formed pole group 14 holds an electrolytic solution. The power generation element 10a formed in this manner is sealed with an exterior body 15 made of a square container. A positive electrode terminal 16 protruding to the outside of the outer package 15 is connected to the positive electrode 11 of the power generation element 10a, and a negative electrode terminal 17 protruding to the outside of the outer package 15 is connected to the negative electrode 12 of the power generation element 10a. In the battery 10, as shown in FIGS. 1A and 1B, the outer package 15 has a width W, a height H, and a thickness T.

  The positive electrode terminal 16 and the negative electrode terminal 17 are flat members having a flat shape in a direction orthogonal to the width direction of the battery and having a predetermined thickness t. Specifically, as shown in FIG. 1 (a), the positive electrode terminal 16 and the negative electrode terminal 17 are arranged such that the width direction of each terminal 16, 17 is substantially parallel to the thickness direction of the exterior body. Is attached. Further, as shown in FIG. 1B, the positive electrode terminal 16 and the negative electrode terminal 17 are arranged at equal intervals from the center 18 in the width direction of the outer package 15 by a distance L. Here, the distance L is the distance from the center in the width direction of each battery 10A, 10B to the terminals 16, 17. The positive terminal 16 protrudes from one side 21 of the outer package 15, and the negative terminal 17 protrudes from the opposite other side 22 opposite to the first side 21 of the outer package 15.

  When the battery 10 of this embodiment is connected to another battery 10 of the same shape and used as an assembled battery, the two batteries 10 are shifted in the width direction and stacked in the thickness direction. A terminal protruding from one side surface 21 and a terminal protruding from the other side surface 22 of the other battery are arranged so as to overlap in the thickness direction of the battery 10.

  Thus, since the battery 10 of this embodiment is attached to the power generation element 10a so that the width direction of the terminals 16 and 17 is substantially parallel to the thickness direction of the exterior body 15, the positive electrode terminal 16 and the negative electrode By arranging the terminals 17 so as to coincide with the thickness direction of the battery (on the same straight line), the surfaces of the two terminals 15 and 16 to be connected can be arranged in the same plane. Therefore, for example, the positive electrode terminal 16 of one battery and the negative electrode terminal 17 of the other battery can be directly connected using a welding plate (connecting member) having a simple flat plate shape. The space required for connecting the terminal 17 can be kept small. Furthermore, by directly connecting the positive electrode terminal 16 and the negative electrode terminal 17, space efficiency is improved, and an assembled battery that does not greatly reduce the energy density and input / output energy density from the unit cell 10 can be obtained.

  In addition, by overlapping the adjacent batteries 10 approximately half of each other, that is, by overlapping the portions 24 and 25, the plurality of batteries 10 are arranged in a substantially gap-free state. The positive terminal 16 and the negative terminal 17 can be connected to each other. Thereby, the some battery 10 can be assembled | assembled still more compactly.

Next, an example in which an assembled battery is configured by combining a plurality of batteries 10 will be described with reference to FIGS.
2 to 4, in order to facilitate understanding, among the plurality of batteries 10, one battery is 10A, the battery adjacent to the positive terminal 16 of the battery 10A is 10B, and the battery 10B is adjacent. The reverse battery is identified as 10C.

  The assembled battery 30 includes a plurality of batteries 10, each battery 10 is stacked in an approximately W / 2 stack in the width direction and alternately stacked in two stages in the thickness direction, and the positive electrode terminal 16 of one battery 10 </ b> A, The negative terminal 17 of the adjacent battery 10B is connected by welding with a welding plate 19 as a member, and the negative terminal 17 of one battery 10A and the positive terminal 16 of the adjacent battery 10B and the opposite battery 10C are connected. Connected.

  In this assembled battery 30, the positive terminal 16 of one battery 10 </ b> A and the negative terminal 17 of an adjacent battery 10 </ b> B are arranged in a straight line in the thickness direction of the battery, and are adjacent to the negative terminal 17 of one battery 10 </ b> A. The battery 10B and the positive electrode terminal 16 of the battery 10C on the opposite side are stacked so as to be arranged in a straight line in the battery thickness direction. In addition, as shown in FIG. 3, each terminal 16 and 17 of the batteries 10A to 10C of the present embodiment has a flat shape in the thickness direction of the battery, and has a predetermined thickness.

  In order to connect the positive electrode terminal 16 of one battery 10A and the negative electrode terminal 17 of the adjacent battery 10B, for example, as shown in FIG. 4A, both terminals 16 and 17 are on the same straight line. In the state where both terminals 16 and 17 extend straight in the protruding direction, the welding plate 19 is disposed so as to straddle the surfaces of both terminals 16 and 17, and both terminals 16 and 17 are welded or the like. Can be connected.

  Here, conditions for arranging the positive electrode terminal 16 of one battery 10A and the negative electrode terminal 17 of the adjacent battery 10B so as to overlap each other in the thickness direction of the battery will be considered with reference to FIG.

FIG. 4A is a diagram showing a state in which the batteries are packed most densely in the width direction.
As shown to Fig.4 (a), the state which each battery contacted in the battery width direction will be in the state where batteries were packed most closely. Thus, when the batteries are packed most closely in the width direction, the center of the battery in the width direction of each terminal must be located at a position W / 4 from the side surface on the outer side in the width direction. Here, the thickness of the terminal is given by t, and the distance from the outer side surface in the width direction of the battery to the center of the terminal is L + t / 2.

L + t / 2 = W / 4
L = W / 4−t / 2 (1)

That is, in (1), adjacent batteries are packed most closely in the width direction. Therefore, the minimum value of the variable L indicating the position in the width direction of the terminal is W / 4−t / 2.

FIG. 4B is a diagram illustrating a case where the batteries are packed most sparsely in the width direction.
As shown in FIG. 4B, when the terminals are arranged along the side surfaces in the width direction of the batteries, the batteries are packed most sparsely in the width direction. As described above, when the batteries are packed most sparsely in the width direction, the side surface on the outer side in the width direction of the terminal of one battery is arranged at a position W / 2 from the center in the width direction. Therefore, the following relationship holds.

L + t = W / 2
L = W / 2−t (2)

That is, in (2), adjacent batteries are packed most sparsely in the width direction. Therefore, the maximum value of the variable L indicating the position in the width direction of the terminal is W / 2−t.

From (1) and (2), the regions where the terminals can be arranged so as to overlap in the thickness direction are as follows.

W / 4-t / 2 ≦ L <W / 2-t (3)

  The state where the batteries are arranged most densely in the width direction and the terminals are completely overlapped in the thickness direction is the state shown in FIG. 5C, that is, when L = W / 4−t / 2. It becomes.

  As described above, in the present embodiment, the assembled battery 30 is configured by stacking the batteries 10 so that the plurality of batteries 10 are shifted in the width direction, that is, approximately W / 2 are overlapped to form two stages in the thickness direction. Is done. Thereby, it becomes possible to arrange a plurality of batteries 10 densely without gaps, and the assembled battery 30 can be made more compact.

  Moreover, in this embodiment, the terminals 16 and 17 of the adjacent battery 10 are arrange | positioned on the straight line in the thickness direction of a battery, respectively, and the terminals 16 and 17 are piled up and welded with the welding board 19. FIG. Can be easily connected. And since both the terminals 16 and 17 are reliably connected by welding through the flat plate-shaped welding board 19, a contact resistance is suppressed and the fall of the energy density and input-output energy density by connection are suppressed.

  In particular, since the battery 10 of the present embodiment has a flat shape extending in the width direction, the battery 10 can be easily stacked in the thickness direction. Therefore, the space efficiency of the whole assembled battery can be increased and the energy density can be increased. Even if the battery 10 has a slightly curved shape instead of a flat shape, if the terminals 16 and 17 can be arranged in a straight line by overlapping two stages in the thickness direction, The effect of increasing the energy density is obtained.

  In the above description, the connection member for connecting the terminals 16 and 17 has been described as being connected by welding using the flat plate-shaped welding plate 19. However, the present invention is not limited to this, and the terminals 16 and 17 are arranged in a straight line. You may connect using another connection member. Even when other connection members are used, since the terminals 16 and 17 are arranged in a straight line, the terminals can be connected without occupying a large space.

From the viewpoint of energy density, the relationship between the battery thickness T and the battery width W is from the viewpoint of ease of pole group winding, ease of current collection structure, and volume energy density.

3.0 ≦ W / T ≦ 4.5 (4)

And most preferably W / T = 4.0.

  In the present embodiment, a flat battery is exemplified as the battery 10 to which the present invention is applied. However, the present invention is not limited to this, and the present invention can be applied to batteries of other shapes such as a rectangular battery.

  In the present embodiment, the assembled battery is configured by stacking a plurality of batteries 10 in two layers in the thickness direction. However, the present invention is not limited to this, and for example, a configuration in which three or more assembled batteries are stacked. Even so, it is possible to configure an assembled battery that is compact and can suppress a decrease in energy density and input / output energy density.

  Further, in the present embodiment, the negative electrode terminal of the battery adjacent to the positive electrode terminal of one battery in the thickness direction, and the positive electrode terminal of the battery adjacent to the negative electrode terminal of the one battery adjacent to the thickness direction. As an example, an assembled battery in which a plurality of batteries are connected in series with each other has been described. However, a positive electrode terminal of a battery adjacent to the positive electrode terminal of one battery in the thickness direction, and It is obvious that an assembled battery in which a plurality of batteries are connected in parallel can be obtained by connecting the negative electrode terminal and the negative electrode terminal of the battery adjacent to the opposite side in the thickness direction, such an assembled battery. Is also within the scope of the present invention.

  INDUSTRIAL APPLICABILITY The present invention is suitable for application to a battery and an assembled battery in which a battery is formed by laminating a layer with a separator interposed between a positive electrode and a negative electrode, and a plurality of these batteries are combined to form an assembled battery. .

(A) A perspective view showing a battery according to the present invention, (b) a plan view showing a battery according to the present invention. It is a top view which shows the assembled battery which concerns on this invention. It is a side view which shows the assembled battery which concerns on this invention. (A)-(b) is a schematic diagram which shows the overlapping pattern of the assembled battery which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Battery 10A One battery 10B Adjacent battery 10C Adjacent battery and reverse battery 11 Positive electrode 12 Negative electrode 13 Separator 16 Positive electrode terminal 17 Negative electrode terminal 19 Welding plate 21 One side surface 22 One side and opposite side 30 Assembly battery 31, 32 Straight line L distance

Claims (4)

An exterior body covering the power generation element, a positive electrode terminal projecting from one side surface of the exterior body, and a negative electrode terminal projecting on the opposite side to the one side surface,
The positive electrode terminal and the negative electrode terminal each have a flat plate shape, and are attached to the power generation element such that the width direction of each terminal is substantially parallel to the thickness direction of the exterior body,
The battery, wherein the positive electrode terminal and the negative electrode terminal protrude from each other in the width direction of the outer package.   2. The battery according to claim 1, wherein the positive electrode terminal and the negative electrode terminal protrude from each other in the opposite direction at equal intervals from the width direction center of the outer package. A plurality of the batteries according to claim 1 or 2,
Each battery is alternately stacked so as to have a plurality of stages in the thickness direction by shifting in the width direction, one terminal of one battery and the terminal of the battery adjacent in the thickness direction, and the other of the one battery An assembled battery comprising: a terminal connected to a battery adjacent in the thickness direction; and a terminal of a battery adjacent to the opposite side.   The terminal of the battery adjacent to the one terminal of the one battery in the thickness direction, and the terminal of the battery adjacent to the other terminal of the one battery and the battery adjacent to the thickness direction are respectively The assembled battery according to claim 3, wherein the battery packs are stacked so as to be arranged in a straight line in the thickness direction.

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