JP6540273B2 - External connection terminal structure of battery pack - Google Patents

Description

  The present invention relates to an external connection terminal structure of a battery pack including a plurality of secondary batteries.

  Secondary batteries are used in various fields because of their high reliability, and various sizes are manufactured depending on the required capacity. In addition, the cost of the secondary battery is too high if it is attempted to achieve a battery of optimum size for each application with one battery. Therefore, by connecting a plurality of unit cells, the battery is often used as a battery pack having a desired capacity.

  A conventional battery assembly is disclosed in FIG. 3 of Patent Document 1 (Japanese Unexamined Patent Application Publication No. 2012-238492). Specifically, as shown in FIG. 10, a part of the assembled battery 101 is composed of two single cells (the first secondary battery 103 and the second secondary battery 105), and the first secondary battery A first external terminal 115 is provided on the top surface of the electrode 103, and a second external terminal 125 is provided on the top surface of the second secondary battery 105 so as to be exposed. As shown in FIG. 11, the first and second external terminals 115, 125 are electrically disposed in the pole posts 117, 127 which are partially disposed in the battery case 107, 111 and fixed by the bushings 123, 133. It is connected. In the assembled battery 101, the first external terminal 115 and the second external terminal 125 connect the connection plate 120 in a state where the first secondary battery 103 and the second secondary battery 105 are arranged side by side. It is fixed through.

  The first secondary battery 103 is provided with a second external terminal 125 'connected to the first external terminal of another secondary battery (not shown). When the first secondary battery 103 is disposed at one end of the battery pack 101, the second external terminal 125 ′ constitutes a positive electrode terminal or a negative electrode terminal of the battery pack 101. On the other hand, the second secondary battery 105 is provided with a first external terminal 115 'connected to the second external terminal of another secondary battery not shown. When the second secondary battery 105 is disposed at the other end of the battery pack 101, the first external terminal 115 'constitutes a negative electrode terminal or a positive electrode terminal of the battery pack 101.

  As shown in FIGS. 10 and 11, the first external terminal 115 is provided with a through hole 137 through which the bolt 147 penetrates, and the second external terminal 125 is provided with a through hole 143 through which the bolt 147 penetrates. It is done. Further, at both ends of the connection plate 120, through holes (not shown) through which the bolts 147 pass are provided. When a bolt 147 is inserted through the through hole 137 of the external terminal 115 and one through hole of the connection plate 120 and the nut 141 is screwed into the screw portion 149 of the bolt 147, the external terminal 115 and one end of the connection plate 120 Is connected. On the other hand, when the bolt 147 is inserted through the through hole 143 of the external terminal 125 and one of the through holes of the connection plate 105 and the nut 141 is screwed into the screw portion 149 of the bolt 147, the other end of the external terminal 125 and the connection plate 120 The department is connected. The connection plate 125, the bolt 147 and the nut 141 are made of a conductive material. The secondary batteries 103 and 105 adjacent to each other are electrically connected via the connection plate 120 connecting the external terminals 115 and 125, the bolt 147, and the nut 141.

JP 2012-238492 A (FIG. 3)

  However, in the conventional battery pack, when electrically connecting the secondary batteries, the bolt and nut fastening operation using the connection plate has a large number of parts, and if the number of connection points is increased, the working efficiency is improved. There is a problem of getting worse. In particular, the handling of the nut, which is a small part, may be a burden on the operator at the actual work site, for example, the operator must hold the nut or bolt with a finger while screwing the nut in place. There are many. Although it is conceivable to form an internal thread directly on the external terminal, if the internal thread is directly formed, burrs may remain on the internal thread, or the thread may be deformed or distorted, so that the external thread of the bolt is engaged with the internal thread. Sometimes things can not happen.

  An object of the present invention is to provide an external connection terminal structure of a battery pack that allows a worker to easily and reliably perform a connection operation with a small number of parts.

  The external terminal connection structure of a battery pack to which the present invention is to be improved includes a first secondary battery having a first external terminal and a second secondary battery having a second external terminal. In the assembled battery in which the first secondary battery and the second secondary battery are arranged adjacent to each other, the first external terminal provided in the first secondary battery and the second secondary battery are provided. It is the external terminal connection structure of the assembled battery which electrically connects with the 2nd external terminal.

  The first external terminal and the second external terminal each include a first terminal portion and a second terminal portion. The first terminal portion and the second terminal portion are configured to face each other in a state where the battery case of the first secondary battery and the battery case of the second secondary battery are disposed adjacent to each other There is. As an aspect in which the first terminal portion and the second terminal portion face each other, for example, the contact surfaces of the first terminal portion and the second terminal portion are the first secondary battery and the second secondary battery. Between the first secondary battery and the second secondary battery in a state in which the first terminal portion and the second terminal portion are in contact with each other when the contact surface of the battery is substantially flush with the contact surface of the battery When a gap is generated, the contact surfaces of the first terminal portion and the second terminal portion may cross the contact surfaces of the first secondary battery and the second secondary battery.

  The first external terminal has a structure in which a female screw member having a first through hole is insert-molded in the first terminal portion. This female screw member is provided with a female screw on the inner peripheral surface of the first through hole.

  The second external terminal has a structure in which a second through hole is formed in the second terminal portion. The second terminal portion is configured to align and communicate with the first through hole of the female screw member in a state where the first terminal portion and the second terminal portion are in contact with each other.

  A female screw is inserted until a bolt member provided with an external thread is inserted into the second through hole of the second terminal portion and the head of the bolt member presses the second terminal portion against the first terminal portion. The male screw of the bolt member is screwed into the female screw of the member.

  In the case where a plurality of secondary batteries are combined to produce an assembled battery by adopting such an external terminal connection structure, the external terminals of two adjacent secondary batteries when the plurality of secondary batteries are arranged. Face each other. In this state, the external terminals are electrically connected directly and the secondary batteries are fixed simply by tightening the two external terminals with a bolt member. Therefore, the assembly operation of the battery assembly can be facilitated (assembly cost can be reduced). In particular, since the female screw member is insert-molded into the first terminal portion as an insert, it is not necessary for the operator to hold the female screw member with a finger during connection work, and the female screw can be used as the first terminal portion. There is no burr remaining on the internal thread portion or deformation or distortion of the thread as compared with direct formation. Therefore, there is an advantage that deformation of the female screw does not cause the case where the male screw of the bolt member can not be screwed with the female screw of the female screw member. Further, since the external terminals can be directly connected to each other, the conventional connection plate and connection cable are not required, and the reduction of the number of parts (reduction of parts cost) and weight reduction of products (reduction of transportation costs) are realized. Can. Furthermore, the first through hole of the female screw member inserted into the first external terminal (first terminal portion) is inserted into the second through hole of the second external terminal (second terminal portion) Since the bolt members are screwed together, it is possible to maintain the state in which the first terminal portion of the first external terminal and the second terminal portion of the second external terminal are pressed. Therefore, the product stability of the assembled battery can be enhanced.

  Preferably, the first external terminal and the second external terminal are arranged such that the battery case of the first secondary battery and the battery case of the second secondary battery are disposed adjacent to each other. And the second terminal portion are in contact with each other. By thus configuring the first external terminal and the second external terminal, the external terminals of two adjacent secondary batteries are in contact with each other only by arranging the plurality of secondary batteries. The screwing operation with the member becomes easy. Further, when the female screw member and the bolt member are screwed together, it is possible to prevent the external terminal from being greatly deformed or damaged.

  The first and second external terminals can be formed using a commercially available metallic material having conductivity. In addition, it is preferable that the female screw member be formed of a metal having higher conductivity and hardness than the metal forming the first external terminal and the second external terminal. When such a highly conductive metal is used for the female screw member, the female screw portion can function as a conductor, so that the conductivity between the external terminals can be enhanced. Also, even if the bolt member is strongly tightened, the female screw member is not deformed. In addition, even if a gap is generated between the first external terminal and the second external terminal between the adjacent secondary batteries, the electrical connection between the external terminals can be maintained through the female screw member.

  Note that copper or a copper alloy can be used as the metal having higher conductivity than the metal forming the first external terminal and the second external terminal.

  It is preferable to use lead or a lead alloy as the metal forming the first external terminal and the second external terminal. Since lead or lead alloy has the property of being easily plastically deformed, when the bolt member is screwed to the female screw member while both external terminals are pressed, the contact area of both external terminals (both terminal parts) by such plastic deformation Can increase the conductivity between the external terminals.

  The female screw member is provided with a flange portion. The flange portion is located on the side surface side not in contact with the second terminal portion of the first terminal portion in a state where the female screw member is insert-molded to the first external terminal. By arranging the female screw member in such a configuration, the bolt member can be formed into the first through hole only by arranging the battery case of the first secondary battery and the battery case of the second secondary battery adjacent to each other. It is possible to reliably perform the operation of inserting into and screwing the female screw member inserted into the second through hole.

  Although the shape of the flange portion is arbitrary, when the contour shape of the flange portion is polygonal, it is possible to prevent the female screw member from idling after the insert molding of the female screw member into the first external terminal. As such a polygonal flange portion, it is possible to adopt a generally popular hexagonal prism shape or octagonal prism shape flange. Such female screw members are not particularly limited as long as they are made of a conductive metal material. Iron, stainless steel, etc. can be used as such a metal material. In particular, it is preferable to use stainless steel from the viewpoint of preventing rusting of the screw engagement with the bolt member and enabling long-term use.

  The external terminal connection structure described above includes two lead storage batteries included in a battery pack in which the first secondary battery and the second secondary battery arranged adjacent to each other are combined with three or more lead storage batteries. It can apply also when it comprises. Even when the application of this external terminal connection structure is limited to a lead-acid battery assembled battery, the assembly work in the assembled battery can be facilitated, the number of parts can be reduced, the weight of the product can be reduced, and the product can be stabilized.

  According to the present invention, since the female screw member having the first through hole has a structure in which the first terminal portion is insert-molded as an insert, the worker can screw the female screw member with a finger during the connection operation. There is no need to hold the members. Also, as in the case where the female screw is directly formed in the terminal portion, no burrs are left in the female screw and the screw thread is not deformed or distorted. Therefore, the bolt member is screwed into the first terminal portion as an insert. Work can be done securely. Then, when a bolt member having an external thread is inserted into the second through hole of the second terminal portion, the head of the bolt member is in a state of pressing the second terminal portion against the first terminal portion. Since the male screw of the bolt member is screwed into the female screw of the female screw member, both external terminals can be electrically connected simply by tightening the external terminals of the adjacent secondary batteries with the plurality of secondary batteries side by side with the bolt member. It is directly joined and secondary batteries are fixed. As a result, the assembly operation of the battery assembly can be facilitated, the weight of the product can be reduced, and the product can be stabilized.

It is a perspective view which shows an example of the external terminal connection structure of the assembled battery which concerns on this invention. (A) is the top view which expanded a part (1st external terminal) of the external terminal connection structure shown in FIG. 1, (B) is IIB-IIB sectional view taken on the line of (A). (A) is the right view which expanded a part (1st terminal part) of the external terminal connection structure shown in FIG. 1, (B) is the IIIB-IIIB sectional view taken on the line of (A), (C) 2 is an enlarged left side view of a part (first terminal portion) of the external terminal connection structure shown in FIG. (A) and (B) are the right side view and left side view which expanded a part (2nd terminal part) of the external terminal connection structure shown in FIG. 1, (C) is IVC- of (A). It is an IVC line sectional view. It is the figure which expanded a part (bolt member) of the external terminal connection structure shown in FIG. It is an expanded sectional view which shows an example of the connection aspect of a 1st external terminal and a 2nd external terminal. It is an expanded sectional view which shows another example of the connection aspect of a 1st external terminal and a 2nd external terminal. It is an expanded sectional view showing another example of the connection mode of the 1st external terminal and the 2nd external terminal. It is a perspective view which shows the assembled battery which put in order and comprised three secondary batteries (cell). It is a perspective view which shows the external terminal connection structure used with the conventional assembled battery. FIG. 11 is an enlarged cross-sectional view of a part of the conventional external terminal connection structure shown in FIG.

  Hereinafter, embodiments of the present invention will be described in detail. FIG. 1 is a view showing an example of an assembled battery provided with the external terminal connection structure of the present invention. The battery assembly 1 of FIG. 1 is configured to include a first secondary battery 3 and a second secondary battery 5. In the battery assembly 1 of FIG. 1, the first secondary battery 3 and the second secondary battery 5 are disposed adjacent to each other. Each of the first secondary battery 3 and the second secondary battery 5 is constituted by a single battery of a lead storage battery. The first secondary battery 3 is configured such that the opening 7 a of the battery case 7 is sealed by the lid 9 in a state where an electrode plate group (not shown) is accommodated in the battery case 7. The second secondary battery 5 is configured such that the opening 11 a of the battery case 11 is sealed by the lid 13 in a state where an electrode plate group (not shown) is accommodated in the battery case 11.

  The electrode plate group is configured by laminating a positive electrode plate and a negative electrode plate via a separator (retainer). The plurality of positive electrode plates and the plurality of negative electrode plates constituting the electrode plate group are electrically connected by straps formed by welding the current collecting portions of the electrode plates called electrode plate ears. Furthermore, connection conductors between cells and pole posts 17 and 27 described later are welded to the straps. The assembly configured in this manner is inserted as a single cell into the battery cases 7 and 11, respectively, and the battery cases 7 and 11 and the lids 9 and 13 are welded. Then, the first and second external terminals 15, 25 are welded to the pole posts 17, 27 so that the first and second external terminals 15, 25 protrude above the lids 9, 13, and further the lid 9 , 13 are welded in advance, and the battery case 7, 11 is sealed. The first and second secondary batteries 3 and 5 can be obtained by injecting a dilute sulfuric acid electrolytic solution into the battery cases 7 and 11 to form the same.

  On the lid 9 of the first secondary battery 3, a first external terminal 15 electrically connected to the electrode plate group accommodated in the battery case 7 is provided. The first external terminal 15 is composed of a pair of external terminals 15A and 15B. Each of the pair of external terminals 15A, 15B has an insertion hole 19a for inserting the pole post 17 of the electrode plate group and is fixed to the lid 9, as shown in FIGS. 2 (A) and 2 (B). And a first terminal portion 21 electrically connected to a second external terminal 25 (second terminal portion 31) described later. The pole post 17 is fixed to a lead alloy bushing 23 in the battery case 7.

  On the other hand, a second external terminal 25 electrically connected to the electrode plate group housed in the battery case 11 is provided on the lid 13 of the second secondary battery 5. The second external terminal 25 is composed of a pair of external terminals 25A and 25B. Similarly to the pair of external terminals 15A, 15B, the pair of external terminals 25A, 25B also have the insertion holes 29a for inserting the pole posts 27 of the electrode plate group and the second base portion 29 fixed to the lid 13. And a second terminal portion 31 electrically connected to the first external terminal 15 (first terminal portion 21). The pole post 27 is fixed to a lead alloy bushing 33 in the battery case 11.

  In addition, as shown in FIG. 1, on the cover 9 of the first secondary battery 3, a second external terminal 25 ′ (a pair of external terminals 25 ′ connected to the first external terminal of another secondary battery not shown) External terminals 25'A, 25'B) are further provided. When the first secondary battery 3 is disposed at one end of the assembled battery 1, the second external terminal 25 ′ constitutes a positive electrode terminal or a negative electrode terminal of the assembled battery 1. On the other hand, on the cover 13 of the second secondary battery 5, a first external terminal 15 '(a pair of external terminals 15'A, 15'B) is further provided. When the second secondary battery 5 is disposed at the other end of the assembled battery 1, the first external terminal 15 ′ constitutes a negative electrode terminal or a positive electrode terminal of the assembled battery 1.

  In this example, the first and second external terminals 15, 25 have an L shape in which the central axes of the first and second through holes 37, 43 and the central axes of the insertion holes 19a, 29a are orthogonal to each other. Have. "Orthogonal" does not mean a precise 90-degree angle, and welding between the first and second base portions 19 and 29 and the pole posts 17 and 27 can be performed. It means an angle of approximately 90 degrees at which the terminal portion 21 and the second terminal portion 31 can be connected by a bolt member described later.

  The first and second external terminals 15 and 25 are formed of a lead alloy to which tin is added, from the viewpoint of imparting conductivity and terminal strength.

  The connection between the first secondary battery 3 and the pole post 17 and the connection between the second secondary battery 5 and the pole post 27 are made by welding. Specifically, as shown in FIG. 2, the first and second external terminals 15, 25 are formed in the gaps between the pole posts 17, 27, the bushings 23, 33 and the first and second external terminals 15, 25. The lead alloy in which lead alloy is melted is poured from the insertion holes 19a and 29a of the above, and welding is performed by filling the gap.

  The pole post 17 has one end connected to the first and second external terminals 15 and 25 (first and second base portions 19 and 29) as described above, and the other end via a strap (not shown). Connected to the board group. Further, as a material of the pole post 17, for example, a pure lead or a lead alloy with tin addition can be used. In this example, a lead alloy to which tin is added is used from the viewpoint of improving the strength and conductivity of the pole column.

  The first terminal portion 21 of the first external terminal 15 and the second terminal portion 31 of the second external terminal 25 correspond to those of the battery case 7 of the first secondary battery 3 and the second secondary battery 5. It is comprised so that the battery case 11 may oppose in the state arrange | positioned adjacently. Specifically, as shown in FIG. 1, with the battery case 7 of the first secondary battery 3 and the battery case 11 of the second secondary battery 5 arranged adjacent to each other, the external terminal 15A and the external The terminal 25A opposes, and the external terminal 15B and the external terminal 25B oppose each other.

  As shown in FIGS. 3A and 3B, the first external terminals 15 (a pair of external terminals 15A and 15B) are insert-molded in the first terminal portion 21 with the female screw member 35 as an insert. It has a structure. The female screw member 35 has a first through hole 37, and a female screw 39 is formed on the inner peripheral surface of the first through hole 37.

  The female screw member 35 integrally includes a flange portion 41 as shown in FIGS. 3 (B) and 3 (C). The flange portion 41 is on the side not contacting the second terminal portion 31 of the first terminal portion 21 in a state where the female screw member 35 is insert-molded into the first external terminal 15 (the first terminal portion 21). positioned.

  In this example, in order to prevent the female screw member 35 insert-molded into the first external terminal 15 from idling, the flange portion 41 is formed of a nut having an outer peripheral shape of a hexagonal column shape. Although FIG. 3 illustrates that the flange portion 41 is not embedded in the first terminal portion 21, in actuality, a part of the flange portion 41 is embedded in the first terminal portion 21. There is. The female screw member 35 is formed of generally available stainless steel.

  As shown in FIGS. 4A to 4C, the second external terminal 25 (a pair of external terminals 25A and 25B) has a second through hole 43 formed in the second terminal portion 31. It has a structure. The second terminal portion 31 is configured to align and communicate with the first through hole 37 of the female screw member 35 in a state where the first terminal portion 21 and the second terminal portion 31 are in contact with each other. ing. In this example, the second through hole 43 has a structure through which the bolt member 47 penetrates, but an internal thread to be screwed with the external thread 49 of the bolt member 47 is formed on the inner peripheral surface of the second through hole 43 May be

  As shown in FIG. 1, a bolt member 47 is inserted in the second through hole 43 of the second terminal portion 31. The bolt member 47 is provided with an external thread 49, as shown in FIG. The male screw 49 of the bolt member 47 first passes through the second through hole 43, and further, until the head portion 47a of the bolt member 47 presses the second terminal portion 31 against the first terminal portion 21. The 47 male threads 49 are screwed into the female threads 39 of the female screw member 35. Thus, the external terminal connection structure 51 of this example is configured.

  When such an external terminal connection structure 51 is adopted, when the first secondary battery 3 and the second secondary battery 5 are arranged side by side, the first external terminals 15 (a pair of external terminals 15A, 15B) and the The two external terminals 25 (a pair of external terminals 25A, 25B) face each other. By tightening the first external terminal 15 and the second external terminal 25 with the bolt member 47 in this state, the first external terminal 15 and the second external terminal 25 are electrically connected directly to each other. The secondary battery 3 and the second secondary battery 5 are fixed. Furthermore, in the first through hole 37 of the female screw member 35 embedded as an insert in the first external terminal 15 (first terminal portion 21), the second external terminal 25 (second terminal portion 31) When the bolt members 47 inserted into the second through holes 43 are screwed together, the first terminal portion 21 of the first external terminal 15 and the second terminal portion 31 of the second external terminal 25 are pressed. State is maintained.

  Furthermore, in this example, the first external terminal 15 and the second external terminal 25 are disposed such that the battery case 7 of the first secondary battery 3 and the battery case 11 of the second secondary battery 5 are adjacent to each other. The first terminal portion 21 and the second terminal portion 31 are configured to be in contact with each other. That is, only by arranging the first secondary battery 3 and the second secondary battery 5, the first external terminal 15 abuts on the second external terminal. Therefore, the screwing operation of the female screw member 35 and the bolt member 47 is easy, and large deformation and breakage of the external terminal when the female screw member 35 and the bolt member 47 are screwed are unlikely to occur.

  In this example, the first external terminal 15 and the second external terminal 25 are both formed of a lead alloy. Since lead alloy is susceptible to plastic deformation, when the bolt member 47 (male thread 49) is screwed onto the female thread member 35 (female thread 39) in a state where the first external terminal 15 and the second external terminal 25 are pressed, the first The contact area between the second terminal portion 31 and the second terminal portion 31 is increased, and the conductivity between the first external terminal 15 and the second external terminal 25 can be enhanced.

  Further, the female screw member 35 is formed of a metal that is higher in hardness and higher in conductivity than the metal (lead alloy) that forms the first external terminal 15 and the second external terminal 25. As such a metal, in this example, a copper alloy (the brass core of JIS H 3250) which is easily available on the market is used. The female screw member 35 formed of such highly conductive metal functions as a conductor to enhance the conductivity between the first external terminal 15 and the second external terminal 25. The female screw member 35 is higher in hardness than a lead alloy and does not deform. Therefore, even if the bolt member 47 is strongly tightened to the female screw member 35, the female screw member 37 is not deformed. Also, even if a gap is generated between the first external terminal 15 and the second external terminal 25, the electrical connection between the first external terminal 15 and the second external terminal 25 via the female screw member 35 is achieved. The connection is maintained.

  Here, a method of manufacturing the first external terminal 15 will be briefly described. First, a brass core (JIS H 3250) constituting the female screw member 35 of the first external electrode 15 is fixed to an L-shaped mold. A melted lead alloy (a mixture of 6% tin) is poured into a mold on which a brass core is fixed to obtain an L-shaped insert-molded body (first external terminal 15).

  As shown in FIG. 2, the obtained first external terminal 15 has the first base portion 19 provided with the ring-shaped ring portion 20 forming the insertion hole 19a and the brass core (female screw member 35) inserted therein. It comprises the first terminal portion 21. The dimensions of the first external terminal 15 are, as shown in FIG. 2, the length dimension of the first base portion 19: 61.5 mm, the width dimension of the first terminal portion 21: 30 mm, the first terminal portion 21. Height dimensions: 42 mm, thickness dimensions of the first base portion 19 and the first terminal portion 21: 10 mm.

  The ring portion 20 has a width of the first base portion 19 with the center of the insertion hole 19a separated by 17.5 mm in the longitudinal direction of the first base portion 19 from the left end of the figure with reference to FIG. It is arranged to be located at the center of the direction. In addition, the ring part 20 inclines the outer periphery and inner periphery of the ring part 20, in order to make the taking-out after shaping | molding of an insert molding object easy. Specifically, the inner diameter of the upper portion 20a of the ring portion 20 is 17 mm, the inner diameter of the lower portion 20b is 17.5 mm, the outer diameter of the upper portion 20a is 28 mm, and the outer diameter of the lower portion 20b is 26 mm.

  Further, the brass core (female screw member 35) is a first external terminal in which the central axis of the brass core (female screw member 35) is spaced downward 15 mm from the upper end of the figure with reference to FIG. 2 (B). It is arrange | positioned so that it may be located in the center of 15 width directions.

  Further, referring to FIG. 3, the brass core is divided into a female screw member 35 having a female screw 39 formed in the first through hole 37 and a flange portion 41 (nut) exposed to the outside. The female screw member 35 has an outer diameter of 15 mm and a length of 10 mm. The flange portion 41 (nut) has an outer diameter of 20 mm and a thickness of 5 mm.

  In the second external terminal 25, the brass core (insert) of the first external terminal 15 does not exist, and the dimension of the second through hole 43 is substantially the same as that of the first through hole 37. .

  As shown in FIG. 2, FIG. 3, and FIG. 6, the surface of the first terminal portion 21 where the flange portion 41 (nut) is not exposed is brought into contact with the second terminal portion 31. After arranging the first secondary battery 3 and the second secondary battery 5 so that the second external terminal 25 and the second external terminal 25 are in contact, the bolt member 47 is passed through the second through hole 37 of the second external terminal 25. Temporarily fix. Thereafter, using a torque wrench, the necessary torque is given, and when the bolts are completely fixed, the external terminal connection structure 51 is completed.

  As a case where the first terminal portion 21 of the first external terminal 15 and the second terminal portion 31 of the second external terminal 25 are connected, as shown in FIG. 1 and FIG. When the contact surfaces of the terminal portion 21 and the second terminal portion 31 are substantially coplanar with the contact surfaces of the battery case 7 and the battery case 11, as shown in FIG. In the case where the gap g is generated between the battery case 7 and the battery case 11 in a state where the second terminal unit 31 is in contact, as shown in FIG. 8, the first contact unit 21 and the second contact unit In some cases, the contact surface with 31 is orthogonal to the contact surfaces of the battery case 7 and the battery case 11. These connection structures make it possible to eliminate the need for a connection plate, which has conventionally been necessary, and to electrically connect two secondary batteries (unit cells) with only bolts. In particular, by using the connection structure shown in FIG. 7, it is possible to cope with a liquid lead storage battery which is expected to generate a bulge of the battery case. Further, by using the connection structure shown in FIG. 8, the bolt member can be further easily tightened.

  FIG. 9 shows two external terminal connection structures in an assembled battery in which three lead storage batteries comprising a third secondary battery 53 in addition to the first secondary battery 3 and the second secondary battery 5 are combined. An example using (the external terminal connection structure 51 and the external terminal connection structure 55) is shown. As described above, even if the number of secondary batteries (unit cells) constituting the assembled battery increases, the assembled battery can be easily assembled, and therefore, it is easy to provide the assembled battery according to the capacity.

  When the external terminal connection structure 51 of this example is used, when the first secondary battery 3 and the second secondary battery 5 are aligned, the first external terminal 15 and the second external terminal 25 face each other. In this state, when the first and second external terminals 15 and 25 are tightened by the bolt member 47, the first external terminal 15 and the second external terminal 25 are electrically connected directly, and the first secondary Battery 3 and second secondary battery 5 are fixed. As a result, the assembly operation of the assembled battery is facilitated, and the assembly cost is reduced. Further, since the conventional connection plate and connection cable are not required, the number of parts of the battery assembly can be reduced, and the weight of the battery assembly can be reduced. Furthermore, the bolt member 47 inserted (screwed) into the second through hole 43 (female screw 45) of the second external terminal 25 (second terminal portion 31) is the first external terminal 15 (first). The first terminal portion 21 of the first external terminal 15 and the second of the second external terminal 25 are screwed into the first through hole 37 (female screw 39) inserted in the terminal portion 21) of the second embodiment. The state in which the terminal portion 31 is pressed is maintained, and the product stability of the assembled battery 1 is enhanced.

  In addition, when assembling the assembled battery which consists of six single cells using the external terminal connection structure 51 of this example, compared with the case where an external terminal is connected and assembled using the conventional connection plate, it is an operation | work The time was reduced by about 40%, and the total weight of the assembled battery was reduced by about 50%.

1 assembled battery 3 first secondary battery (single battery)
5 Second rechargeable battery (single battery)
7, 9 battery case 11, 13 lid 15 first external terminal 17, 27 pole post 19 first base 19a insertion hole 20 ring 20a upper 20b lower 21 first terminal 23, 33 bushing 25 second External terminal 29 second base portion 29a insertion hole 31 second terminal portion 35 female screw member 37 first through hole 39 female screw 41 flange portion (nut)
43 second through hole 45 female screw 47 bolt member 47a head 49 male screw 51 external terminal connection structure

Claims (8)

The first external terminal and the first external terminal in an assembled battery including a first secondary battery having a first external terminal and a second secondary battery having a second external terminal, which are disposed adjacent to each other. An external terminal connection structure of a battery pack electrically connecting a second external terminal,
The first external terminal and the second external terminal face each other when the battery case of the first secondary battery and the battery case of the second secondary battery are disposed adjacent to each other Terminal and the second terminal, respectively,
The first external terminal has a structure in which a female screw member in which a female screw is formed on an inner peripheral surface of a first through hole in the first terminal portion is insert-molded as an insert,
The second external terminal is aligned with the first through hole of the female screw member in a state where the first terminal portion and the second terminal portion are in contact with the second terminal portion. And a second through hole communicating with each other.
A bolt member having an external thread is inserted into the second through hole of the second terminal portion, and a head of the bolt member presses the second terminal portion against the first terminal portion. The external terminal connection structure of the assembled battery, wherein the male screw of the bolt member is screwed to the female screw of the female screw member until the above-mentioned.   The first external terminal and the second external terminal are disposed such that the battery case of the first secondary battery and the battery case of the second secondary battery are disposed adjacent to each other. The external terminal connection structure of the assembled battery according to claim 1, wherein the terminal portion and the second terminal portion are configured to be in contact with each other.   3. The external terminal connection of the assembled battery according to claim 1, wherein the female screw member is formed of a metal having higher conductivity and hardness than a metal forming the first external terminal and the second external terminal. Construction.   The external terminal connection structure for a battery assembly according to claim 3, wherein the metal forming the first external terminal and the second external terminal is lead or a lead alloy.   The external terminal connection structure of the assembled battery according to claim 3, wherein the female screw member is formed of copper or a copper alloy. The female screw member includes a flange portion,
The said flange part is located in the side which is not in contact with the said 2nd terminal part of the said 1st terminal part in the state by which insert molding of the said internal thread member was carried out to the said 1st external terminal. External terminal connection structure of the battery pack.   7. The external terminal connection structure for a battery assembly according to claim 6, wherein an outline shape of the flange portion is a polygon.   8. The set according to claim 7, wherein the first secondary battery and the second secondary battery are two adjacent lead-acid batteries included in an assembled battery in which three or more lead-acid batteries are combined. Battery external terminal connection structure.

Images