JP2000243370A - Battery system and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect the temperature of an inside of a battery system precisely and easily. SOLUTION: A collector plate connection part 36 of a through hole for electrically connecting an electrode of an adjacent battery is formed on a barrier plate 34 of each of batteries in a battery case. A thermal conductive member 78 formed from material having excellent electric conductivity and thermal conductivity is welded to the collector plate connection part 36 in a state that the thermal conductive member 78 is supported by two collector plate connection bodies 70 which are contact with a collector plate on a negative electrode side 64 and a collector plate on a positive electrode side 54. A part of the thermal conductive members 78 protrude outside a battery system, and thus the temperature inside the battery system is detected by mounting a thermistor or the like on the part of the thermal conductive member 78 protruded outside the battery system.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an assembled battery and a method of manufacturing the same, and more particularly, to an assembled battery formed by connecting a plurality of batteries in series and a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, as this type of assembled battery, there has been proposed a battery in which a concave portion is provided near a battery electrode of a battery case formed of resin and a thermometer is provided in the concave portion. . Usually, an appropriate temperature range is set for a battery according to its characteristics. If the battery is used outside this temperature range, the battery may not be used efficiently, may not operate at all, or may be damaged depending on the temperature depending on the temperature. For this reason, the proposed assembled battery can detect the temperature of the battery so that the temperature of the battery can be managed.

[0003]

However, the proposed assembled battery has a problem that the temperature of the battery cannot be accurately detected. Because resin has low thermal conductivity,
A temperature difference occurs between the electrode and the thermometer, and the battery cannot accurately detect the temperature. To solve such problems, it is conceivable to consider the difference between the temperature of the electrode caused by the presence of the resin and the temperature measured by a thermometer. However, when the temperature of the battery changes, the detected temperature changes. The problem of not being able to follow is not solved.

The above problem can be solved by installing a thermometer directly inside the battery pack. However, in a battery pack adopting a sealed structure, the structure of the battery pack becomes complicated because it is necessary to consider the seal of the mounting portion of the thermometer. A new problem arises that the number of parts increases.

The purpose of the present invention is to easily and more accurately detect the temperature inside the battery pack without increasing the number of parts. Another object of the present invention is to provide a method of manufacturing an assembled battery that can more accurately detect the internal temperature. Still another object of the present invention is to provide a method of manufacturing a battery case used for an assembled battery capable of detecting the internal temperature more accurately.

[0006]

Means for Solving the Problems and Actions and Effects Thereof The present invention employs the following means in order to at least partially achieve the above object.

A battery assembly according to the present invention is a battery assembly comprising a plurality of batteries connected in series, the partition having a partition for partitioning the batteries adjacent to each other, and housing the batteries. A case, an electrode connector disposed on the partition of the battery case and electrically connecting the electrodes of the adjacent batteries, and a contact portion formed of a material having excellent thermal conductivity and in contact with the electrode connector. And a heat conductor having an exposed portion exposed to the outside of the battery case.

In the battery pack according to the present invention, the temperature inside the battery pack is transmitted to the outside of the battery case by bringing the heat conductor formed of a material having excellent thermal conductivity into contact with the electrode connector. Therefore, by attaching temperature detecting means such as a thermistor to the exposed portion of the heat conductor exposed to the outside of the battery case, the temperature inside the assembled battery can be detected. Moreover, since the heat conductor is excellent in heat conduction,
Even if a temperature change occurs inside the battery pack, this temperature change can be quickly transmitted to the outside of the battery case.

In the battery assembly of the present invention, the electrode connector is composed of two members, and the heat conductor is provided with the contact portion sandwiched between the two members of the electrode connector. It can also be made to come into contact with. By doing so, the contact area between the heat conductor and the electrode connector can be increased, so that heat conduction to the heat conductor can be promoted. In addition, the term "contact" includes one in which the heat conductor is integrated with the electrode connector by welding, in addition to the one in which the heat conductor is pressed by a bolt.

A first method for manufacturing a battery assembly according to the present invention is a method for manufacturing a battery assembly in which a plurality of batteries are connected in series. A case forming step of forming a resin case having a connection hole for electrically connecting the adjacent batteries and having a through hole penetrating the connection hole and the outside in the partition wall with a resin; A case lid forming step of forming a lid of the battery case having a communication hole communicating with a through hole formed in the partition wall with the same resin as the battery case, and a battery assembling step of assembling the plurality of batteries in the battery case When the lid and the battery case are formed of a material having excellent thermal conductivity, a thermal conductor that extends from the connection hole to the outside of the lid through the communication hole of the lid when the lid and the battery case are joined to the through hole. Insert An electrode connector for assembling an electrode connector for electrically connecting adjacent battery electrodes while sandwiching at least a part of a portion of the inserted heat conductor that has reached the connection hole; The gist of the present invention includes an assembling step and a lid assembling step of assembling the lid to the battery case.

According to the first method of manufacturing a battery assembly of the present invention, it is possible to manufacture a battery assembly including a heat conductor sandwiched between electrode assemblies and partially exposed to the outside. In the assembled battery thus manufactured, the temperature inside the assembled battery is detected by attaching a temperature detecting means such as a thermistor to the heat conductor because the heat conductor transmits the temperature inside the assembled battery to the outside of the battery case. be able to. Here, the heat conductor inserting step may be performed after the battery assembling step, may be performed prior to the battery assembling step, or may be performed in parallel with the battery assembling step. The electrode connecting body assembling step can be performed at any time after the heat conductor inserting step and after the electrode assembling in the battery assembling step, so that after the entire battery assembling step is performed. No need to do it. In addition, assembling in the electrode connecting body assembling step includes assembling with bolts,
An assembly in which the heat conductor and the electrode connector are integrated by welding is also included. The assembling in the lid assembling step includes assembling by bolts, and also includes assembling the lid by heat-sealing the battery case.

A method of manufacturing a battery case according to the present invention is a method of manufacturing a battery case which is formed of resin and accommodates a plurality of batteries and is capable of electrically connecting electrodes of adjacent batteries. A mold forming step of forming a mold for forming a case; and a heat conductive portion for electrically projecting the electrode of the adjacent battery of the formed mold so that a part thereof projects outside the battery case. And a case forming step of forming a battery case by injecting a resin into a mold in which the heat conductor is arranged. Make a summary.

According to the method for manufacturing a battery case of the present invention,
Since the heat conductor is arranged in the mold of the battery case at the time of injection molding, the battery case and the heat conductor can be integrally formed.

A second method of manufacturing a battery pack according to the present invention is a method of manufacturing a battery pack in which a plurality of batteries are connected in series. A battery assembling step of assembling the plurality of batteries; an electrode connector assembling step of assembling an electrode connector that electrically connects electrodes of adjacent batteries while sandwiching a part of the heat conductor; A lid assembling step of assembling a lid formed of the same resin as the case and having a through hole for exposing the heat conductor to the outside to the battery case is provided.

According to the second method of manufacturing a battery assembly of the present invention, it is possible to manufacture a battery assembly having a heat conductor sandwiched between electrode assemblies and partially exposed to the outside. In the assembled battery thus manufactured, the temperature inside the assembled battery is detected by attaching a temperature detecting means such as a thermistor to the heat conductor because the heat conductor transmits the temperature inside the assembled battery to the outside of the battery case. be able to. Here, the electrode connecting body assembling step can be performed at any time after the electrodes are assembled in the battery assembling step, and thus need not be performed after all of the battery assembling steps are performed. The assembling in the electrode connecting member assembling step includes assembling with a bolt and also assembling such that the heat conductor and the electrode connecting member are integrated by welding. Further, the assembling in the lid assembling step includes assembling with a bolt and also assembling in which the lid is heat-sealed to the battery case.

[0016]

Next, embodiments of the present invention will be described with reference to examples. FIG. 1 is an exploded perspective view showing a schematic configuration of an assembled battery 20 according to one embodiment of the present invention. As shown in the drawing, the battery pack 20 of the embodiment includes a battery case 30.
And a plurality of batteries 50 housed in the battery case 30, and a case lid 40 forming a lid of the battery case 30.

The battery case 30 is formed of a resin such as engineering plastics, and has a plurality of partitions 34 formed therein to form a storage section 32 for storing a plurality of batteries 50. A current collector connecting portion 36 serving as a through-hole is formed in the upper part at the center of the partition wall 34. A material having conductivity and excellent heat conductivity (for example, , Iron or nickel) is inserted. In the current collector connecting portion 36, the electrodes of the adjacent batteries 50 are electrically connected, and this connection will be described later.

The case lid 40 is also formed of the same resin as the battery case 30, and has a through hole 42 at a position corresponding to the heat conducting member 78 inserted into the partition 34 of the battery case 30. Therefore, when the case lid 40 is attached to the battery case 30, a part of the heat conductive member 78 penetrates the through hole 42 and projects to the upper surface of the case lid 40. The case cover 40 is assembled to the battery case 30 by heat sealing so that each battery 50 has a sealed structure.

The battery 50 is configured as a nickel-metal hydride battery, and includes a plurality of anodes 52, a plurality of cathodes 62 alternately arranged with the plurality of anodes 52, and ends of the plurality of anodes 52 (FIG. 1). An anode-side current collector 54 connected to the left side),
The cathode 62 includes a cathode-side current collector 64 connected to the ends (the right side in FIG. 1) of the plurality of cathodes 62, and an electrolyte (not shown). The central upper portion of the anode-side current collector 54 and the cathode-side current collector 64 is electrically connected to the cathode-side current collector 64 or the anode-side current collector 54 of the adjacent battery 50 and the two current collector connecting bodies 70. Connection portions 56 and 66 to be connected are formed. Note that the current collector connecting member 70 is formed of a material having excellent conductivity (for example, iron, nickel, or the like). The fitting convex portion 72 is formed.

FIG. 2 shows the assembled battery 20 after assembly.
It is an expanded sectional view which expands and shows the part of the partition 34 of AB cross section in the inside. As shown in the figure, the heat conducting member 78 is sandwiched between the two current collector connecting members 70 and is in contact with the projections 72 of the two current collector connecting members 70. The two current collector connecting members 70 are sandwiched between the anode-side current collector 54 and the cathode-side current collector 64 to form a five-layer sandwich structure as a whole. In the embodiment, the sandwich structure is welded by resistance welding while being pressed. Therefore, the electrical resistance at the contact surface of each member is small. A part of the heat conduction member 78 protrudes outside through the through hole 42 of the case lid 40. Heat conduction member 78
Is formed of a material having excellent thermal conductivity, as described above, the temperature inside the assembled battery 20 can be detected by attaching a temperature detector such as a thermistor to a portion protruding outside. In addition, even if a temperature change occurs inside the battery pack 20, the temperature change is quickly followed, so that the temperature inside the battery pack 20 can be detected more accurately. A groove 7 for arranging an O-ring 76 is provided near the edge of the current collector connecting body 70 on the side where the projection 72 is formed.
4 is formed, and an O-ring 76 is disposed here and pressed against the partition wall 34 of the battery case 30 to seal each of the storage sections 32.

Next, the manner of manufacturing the assembled battery 20 of this embodiment will be described. FIG. 3 is a manufacturing process diagram illustrating an example of a manufacturing process of the assembled battery 20 of the example. The manufacture of the assembled battery 20 starts with a step of preparing the battery case 30 (step S10). In this step, the battery case 3
This is the same as the manufacturing process of No. 0, and preparation (manufacturing) is performed by the manufacturing process of the battery case 30 illustrated in FIG. For the sake of explanation, the description of the manufacturing process of the battery pack 20 of FIG. 3 will be interrupted, and the manufacturing process of the battery case 30 of FIG. 4 will be described here.

The manufacture of the battery case 30 starts with a step of forming a mold of the battery case 30 (step S20). Since the battery case 30 is formed of resin as described above, the mold of the battery case 30 referred to here is a mold for injection molding. Next, the heat conductive member 78 is disposed at a position corresponding to the upper center of the partition 34 of the battery case 30.
2). Subsequently, the battery case 30 is formed by injecting the resin into the mold while maintaining the state where the heat conductive member 78 is arranged (step S24), and the battery case 30 is completed. Since the battery case 30 is injection-molded while maintaining the state in which the heat conductive member 78 is arranged, the heat conductive member 78 can be integrated with the battery case 30.

Returning to the manufacturing process of the battery assembly 20 of FIG. After the battery case 30 is formed and prepared in this manner, the battery 50 is assembled into each of the storage portions 32 of the battery case 30 (step S12), the current collector connecting member 70 is arranged, and the above-described cathode side collector is connected by resistance welding. The sandwich structure including the power plate 64, the current collector connecting member 70, the heat conducting member 78, the current collector connecting member 70, and the anode-side current collecting plate 54 is integrated (step S1).
4). Then, the case lid 40 is put on the battery case 30 and the contact surface is attached by heat sealing (step S16),
The assembled battery 20 of the embodiment is completed.

According to the battery assembly 20 of the embodiment described above, the heat conducting member 78 made of a material having excellent thermal conductivity is integrated with the current collector connecting member 70 inside the battery assembly 20, and Since a part of the battery is projected outside the battery pack 20, the temperature inside the battery pack 20 can be detected through the projecting portion. Moreover, even if a temperature change occurs inside the battery pack 20, the heat conduction member 78 quickly follows the temperature change, so that the temperature inside the battery pack 20 can be detected more accurately.

Further, according to the method of manufacturing the assembled battery 20 of the embodiment, the assembled battery 20 having the above-described effects can be manufactured. Moreover, since the battery case 30 is injection-molded in a state where the heat conductive member 78 is arranged in the mold of the battery case 30, the heat conductive member 78 can be integrated with the battery case 30.

In the assembled battery 20 of the embodiment, the battery 50 is configured as a nickel-metal hydride battery, but may be configured as any other battery.

In the manufacturing method of the assembled battery 20 of the embodiment, the heat conductive member 78 and the current collector connecting member 70 are welded after the battery 50 is assembled. After assembling the plurality of anodes 52 and the anode-side current collector plate 54 and the plurality of cathodes 62 and the cathode-side current collector plate 64, welding of the heat conducting member 78 and the current collector plate connecting member 70 can be performed. Before the battery 50 is completely assembled, the heat conducting member 78 and the current collector connecting body 70 may be welded.

In the method of manufacturing the assembled battery 20 of the embodiment, the heat conducting member 78 and the current collector connecting body 70 are integrated by resistance welding, but may be fastened by bolts or the like.

Further, in the manufacturing method of the assembled battery 20 of the embodiment, the heat conductive member 78 is arranged in the mold of the battery case 30 and the battery case 30 is injection molded. However, the heat conductive member is inserted into the battery case. Alternatively, injection molding may be performed to form an insertion hole, and a heat conducting member may be inserted into the injection molding. FIG. 5 shows an example of a manufacturing process of the assembled battery in this case. In this manufacturing process, first, a battery case is injection-molded using a mold for forming a through hole for inserting a heat conductive member (step S30), and a case lid is similarly injection-molded (step S32). Next, the battery is attached to the storage portion of the battery case (step S34), and a heat conductive member is inserted into an insertion hole formed in the partition of the battery case (step S36). Then, the sandwich structure including the heat conducting member and the current collector connecting body is welded (step S38), and the case lid is heat-sealed (step S40) to complete the assembled battery. In this case, since the heat conductive member is not disposed during the injection molding of the battery case, the battery case can be easily formed.

In the method of manufacturing the assembled battery according to the modified example, the insertion hole for inserting the heat conduction member into the battery case is formed. However, the heat conduction member is press-fitted without forming the insertion hole. Is also good.

The embodiments of the present invention have been described with reference to the embodiments. However, the present invention is not limited to these embodiments, and various embodiments may be made without departing from the scope of the present invention. Of course, it can be carried out.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a schematic configuration of an assembled battery 20 according to one embodiment of the present invention.

FIG. 2 is a cross-sectional view of the assembled battery 20 taken along line AB in FIG.
It is an expanded sectional view which expands and shows the part of the partition wall 34 of a cross section.

FIG. 3 is a manufacturing process diagram illustrating a state of manufacturing the assembled battery 20 of the embodiment.

FIG. 4 is a manufacturing process diagram illustrating a state of manufacturing a battery case 30 used for the assembled battery 20 of the embodiment.

FIG. 5 is a manufacturing process diagram illustrating a state of manufacturing a collective battery of a modified example.

[Explanation of symbols]

20 assembled battery, 30 battery case, 32 storage section, 3
4 partition, 36 current collector connection, 40 case lid, 4
2 through-hole, 50 battery, 52 anode, 54 anode current collector, 56 connection, 62 cathode, 64 cathode current collector,
66 connection part, 70 current collector connection body, 72 convex part, 74
Grooves, 76 O-rings, 78 heat conducting members.

Claims (5)

[Claims] 1. A battery assembly comprising a plurality of batteries connected in series, comprising: a partition for partitioning adjacent batteries of the plurality of batteries, and a battery case for housing the plurality of batteries; An electrode connector disposed on the partition wall of the battery case and electrically connecting the electrodes of the adjacent batteries; a contact portion formed of a material having excellent thermal conductivity and contacting the electrode connector; and the battery And a heat conductor having an exposed portion exposed to the outside of the case. 2. The battery assembly according to claim 1, wherein the electrode connector is made up of two members, and the contact portion of the heat conductor is held between the two members of the electrode connector. An assembled battery that comes into contact with the electrode connection body in the folded state. 3. A method for manufacturing an assembled battery comprising a plurality of batteries connected in series, wherein the plurality of batteries are housed and the adjacent batteries are electrically connected to a partition partitioning the adjacent batteries. Forming a battery case having a connection hole for forming the battery case and having a through hole penetrating the connection hole and the outside in the partition wall, and communicating with the through hole formed in the partition wall of the battery case. A case lid forming step of forming a lid of the battery case having a communication hole with the same resin as the battery case, a battery assembling step of assembling the plurality of batteries in the battery case, and a material having excellent heat conductivity. A heat conductor insertion step of inserting a heat conductor extending from the connection hole to the outside of the lid through the communication hole of the lid when the formed lid and the battery case are joined to each other; Inserted An electrode connector assembling step of assembling an electrode connector that electrically connects electrodes of adjacent batteries while sandwiching at least a part of the portion of the heat conductor that has reached the connection hole; and attaching the lid to the battery. A method of manufacturing an assembled battery, comprising a step of attaching a lid to a case. 4. A method for manufacturing a battery case formed of resin and capable of accommodating a plurality of batteries and electrically connecting electrodes of adjacent batteries, comprising a mold for forming the battery case by injection molding. Forming a mold, and forming a part of the formed mold from a material having excellent thermal conductivity so as to partially project to the outside of the battery case at a portion for electrically connecting the electrodes of the adjacent batteries. A method for manufacturing a battery case, comprising: a heat conductor arranging step of arranging the heat conductor thus formed; and a case forming step of forming the battery case by injecting a resin into a mold in which the heat conductor is arranged. 5. A method for manufacturing an assembled battery in which a plurality of batteries are connected in series, comprising: a battery assembling step of assembling the plurality of batteries in a battery case manufactured according to claim 4; An electrode connector assembly step of assembling an electrode connector body for electrically connecting the electrodes of adjacent batteries while sandwiching a part of the battery case, formed of the same resin as the battery case, and exposing the heat conductor to the outside. A lid assembling step of assembling a lid having a through hole to be exposed to the battery case.