JP2013254745A - Battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a long life and highly reliable nonaqueous electrolyte secondary battery ensuring vibration shock resistance, insulation and airtightness without using compressive stress of a resin component.SOLUTION: The battery includes a battery case having an opening, and a lid being fitted to the opening. The lid includes a portion smaller than the inside dimension of the opening at a part fitted to the opening. The lid and the battery case are bonded by placing a thermoplastic material between the lid and the battery case. The battery case has a positive electrode while the lid has a negative electrode, or the battery case has a negative electrode while the lid has a positive electrode.

Description

  The present invention relates to a battery including a battery case having an opening and a lid plate fitted to the opening.

  As portable devices such as mobile phones are rapidly spreading, high performance secondary batteries have been required as their power source. As such a secondary battery, a non-aqueous electrolyte secondary battery using a substance capable of inserting and extracting lithium ions as a positive electrode and a negative electrode material has been developed and put into practical use.

  In recent years, the non-aqueous electrolyte secondary battery has been used for a wide range of applications such as power assist bicycles and hybrid electric vehicles as well as portable devices. In such a case, since the use environment of the battery is different from that of the portable device, the structure of the non-aqueous electrolyte secondary battery is particularly problematic. Therefore, a sealed battery structure in which a power generation element including a positive electrode and a negative electrode, which is conventionally known, is housed in a battery container will be described.

In the coin-type battery of Patent Document 1, a lead terminal is configured from an electric insulating material such as resin packing from a cover plate, while a battery case having an opening is configured from a bottomed cylindrical body made of metal such as aluminum. Then, the opening is closed with a lid plate, and both are hermetically joined by caulking or laser welding to prevent leakage of the electrolyte, and at the same time, prevent the entry of water and air from the outside of the non-aqueous electrolyte secondary battery. It tries to prevent deterioration.
In the battery of Patent Document 2, the positive electrode end face electrode and the negative electrode end face electrode of the stacked power generation element are electrically connected to the positive electrode terminal and the negative electrode terminal by a conductive adhesive, and the battery case opening and the metal The lid plate is sealed with two types of adhesives, and the sealing between the terminals and the insulation is ensured.

In addition, the form of the sealed battery in which the caulking structure is adopted in the terminal structure is disclosed in FIG.
JP 2005-71649 A JP 2004-179090 A

  However, in the battery disclosed in Patent Document 1, the compressive stress of the resin gasket is used in order to ensure hermeticity. When force is applied to the caulking portion with respect to external force, the bonding force is stably maintained. In addition to this, there is a problem that the caulking force may be weakened due to deterioration of the gasket due to heat cycle over a long period of time, and as a result, a decrease in the airtightness of the battery is inevitable.

  Moreover, in patent document 2, when using two types of adhesive bond layers in order to ensure insulation and airtightness without using the said resin gasket, as disclosed in this patent document 2 When the structure is adopted, there is a problem that various vibrations generated when the battery is mounted on a vehicle such as an automobile (for example, a hybrid electric vehicle) cannot avoid adversely affecting the sealing performance. In addition, since one type of the adhesive layer has electrical conductivity, that is, when a large current charge / discharge is performed for an application such as a hybrid vehicle, heat is generated due to the resistance unique to the adhesive layer. As a result, there was a problem that the adhesive layer was deteriorated and the adhesive strength was lowered.

  The present invention made in view of the above problems will be described below.

(1) In this invention, it is a battery provided with the battery case which has an opening part, and the cover plate fitted to the said opening part, Comprising: The said cover plate is the said in the part fitted with the said battery case. A portion smaller than the inner dimension of the opening is provided, and the lid plate and the battery case are bonded together by disposing a thermoplastic material between the lid plate and the battery case.

  As a specific aspect of the present invention, for example, there is an aspect as shown in FIG. 2 (a) or (b) of the present application. In addition, the cover plate of Fig.2 (a) is concave shape. The concave shape means a shape composed of a flat plate and a plate protruding in a direction substantially perpendicular to the peripheral edge of the flat plate, but does not require geometric precision.

  When a battery to which the present invention is applied is mounted on a vehicle, vibration resistance is improved with respect to vibration in the left-right direction in FIG. 2, and sealing strength can be maintained.

  The thermoplastic material referred to in the present application is a resin material that has excellent sealing properties and high bonding strength with respect to metal materials, and is excellent in heat resistance, chemical resistance, and electrical insulation during normal use. The thermoplastic material is arranged by injection molding.

  A metal can be used for the battery case of the present invention, and the same metal as the battery case or a different metal can be used for the cover plate.

(2) In this invention, it is a battery provided with the battery case which has an opening part, and the cover plate fitted to the said opening part, Comprising: The said cover plate is the inner dimension of the said opening part of the said battery case. The cover plate and the battery case are bonded to each other by arranging a thermoplastic material between the battery case, the cover plate, and the battery case.
As a specific aspect of the present invention, for example, there is an aspect as shown in FIG.

(3) Further, in the present application, the cover plate may be formed of one metal material or one clad material. By using one metal material or one clad material and using it as a terminal, the cost required for manufacturing the battery can be greatly reduced. Furthermore, the shape of the battery is extremely simple, and a battery having no protruding portion can be formed. Therefore, when mounting the battery according to the present invention on a hybrid electric vehicle or the like, a compact configuration can be achieved, and high discharge performance can be exhibited.

  The lid plate shape can be a simple plate shape or a concave shape. However, if the welding area with the thermoplastic resin material is widened, the adhesion strength and airtightness can be secured, the flange for the battery assembly can be easily provided at a low cost, and the cover plate can be made lightweight. Considering what can be done, the concave shape is good.

  Furthermore, the cover plate can be configured such that any part of the cover plate itself exhibits either the positive or negative polarity. The same applies to the battery case. Then, the battery case has a function of becoming a terminal, and the lid plate has a function of becoming a terminal.

(4) In the present invention, in addition to the above configuration (1), (2) or (3), the battery case has a positive polarity and the lid plate has a negative polarity, or the battery case The lid has a negative polarity and the lid plate has a positive polarity.

  The battery case and the cover plate are electrically connected to the positive electrode or the negative electrode of the power generation element inserted into the battery case, respectively, so that polarity is imparted to the battery case and the cover plate.

(5) In the present invention, in addition to the configuration of (1), (2), (3) or (4) above, a thermoplastic material is disposed on the surface of the battery case and / or the surface of the lid plate. The part is surface-treated.

  The surface treatment of the present invention is for improving the adhesion between the battery case and the thermoplastic material. Specifically, it means that fine irregularities are provided in a portion of the surface of the battery case and / or the surface of the lid plate where the thermoplastic material is disposed. Thereby, an anchor effect is exhibited and the adhesiveness of the metal and thermoplastic material which comprise a battery case or a cover board becomes favorable.

(6) The present invention also has a function of a terminal having electrical polarity, and also has a function of a terminal having a polarity different from that of the battery case, and a metal battery case having an opening at one end, In addition, the battery includes a metal lid plate that fits into the inner side surface of the opening, and a gap between the battery case and the lid plate is adhesively sealed with a thermoplastic material.

(7) The present invention is a method of manufacturing a battery in which the configuration shown in the above (1) to (6) is adopted, by disposing a thermoplastic material between the lid plate and the battery case. The lid plate and the battery case are bonded together.
As a method for arranging the thermoplastic material, there is injection molding.

  According to the present invention, the reliability of the long life is high without using the compressive stress of the resin parts for obtaining vibration shock resistance, insulation and airtightness, and the number of parts is reduced because no terminal parts are used. It is possible to provide a low-cost non-aqueous electrolyte secondary battery. Therefore, the present invention is particularly suitable for in-vehicle applications such as for hybrid electric vehicles.

  The best embodiment of the present invention will be described with reference to FIGS.

Example 1
Embodiments of the present invention will be described with reference to the drawings. In these drawings, the same reference numerals are given to constituent members having functions similar to those of the conventional example shown in FIG.

(1) A prismatic nonaqueous electrolyte secondary battery according to Example 1 of the present invention will be described below as an example. Since the fracture | rupture perspective view of the nonaqueous electrolyte secondary battery which concerns on Example 1 was shown in FIG. 3, when this is referred, it will be easy to grasp | ascertain the structure first.

  In the battery of this Example 1, as shown in FIG. 2 (a), a thermoplastic material 6 having non-aqueous electrolyte resistance is melted in one end opening portion of a metal rectangular battery case 5. The metal lid plate 7 is sealed and welded by pouring and cooling.

  The lid plate 7 has a plate shape here, but may have a pan lid shape as shown in FIG. The battery case contains a power generation element (not shown) and is filled with a non-aqueous electrolyte. The power generation element is obtained by winding a positive electrode and a negative electrode in a long cylindrical shape through a separator, and these positive electrode and negative electrode are connected to a current collector plate (not shown).

Since Example 1 shows a non-aqueous electrolyte secondary battery, the metal component on the positive electrode side is made of aluminum or an aluminum alloy that does not dissolve in the non-aqueous electrolyte in the positive electrode battery, and the metal component on the negative electrode side is negative electrode active. Copper or a copper alloy that is not alloyed with the material, nickel-copper clad material, or the like is used.
Accordingly, here, the battery case 5 and the cover plate 8 serving as the battery case are made of aluminum so as to be on the positive electrode side, and the nickel-copper clad material is used for the cover plate 7 serving as the negative electrode side.

(2) Next, the surface treatment for the part where the battery case comes into contact with the thermoplastic resin material will be described.
As a surface treatment method of the aluminum alloy which is the battery case 5, there is an “aqueous solution immersion method” in which the aluminum alloy is immersed in an aqueous solution. In this embodiment, after the aluminum is immersed in an aqueous solution of ammonia (NH 3), it is washed with water and dried. Adopted. As a result, the aluminum surface became an etched surface in which ultrafine recesses were formed.

  On the other hand, as a surface treatment method for copper, which is the cover plate 7 also serving as the negative electrode terminal, the copper surface is brought into contact with an aqueous solution containing an azole compound and an organic acid, and after forming a thick film of the azole compound on the copper surface, further microetching is performed. The surface was submerged by the method, and the adhesion to the resin was remarkably improved.

(3) A method for integrally forming the battery case 5 and the lid plate 7 that also serves as the negative electrode terminal may be simply described because a known method may be used. As shown in FIG. 4, an injection mold (hereinafter referred to as a mold) 9 formed of a metal having excellent heat resistance for forming a thermoplastic material between the lid plate 7 and the cylindrical battery case 5 is as follows. A movable lower mold 9b was provided on the upper surface of the lower mounting plate 9a, and a cylindrical cylindrical battery case 5 was previously installed inside. The movable lower mold 9b was inserted so that the center part fits in the battery case 5.

  A fixed upper die 9 d was provided on the lower surface of the upper mounting plate 9 c and placed so as to be in close contact with the upper surface 5 b of the opening of the battery case 5 and the upper surface of the lid plate 7. A cavity 10 is formed on the lower surface of the fixed upper mold 9d, and the cavity 10 is formed into a square cavity by the lower surface of the fixed upper mold 9d, the inner surface 5a of the battery case 5, and the lid plate side surface 7a.

  The rectangular hollow portion 10 is formed with an injection passage 9d1 penetrating vertically in a part of the ceiling, and a through hole 9c1 penetrating vertically at the same position of the upper mounting plate 9c overlapping the upper opening of the injection passage 9d1. A resin injection port 9c2 is formed at the upper end of the injection path 9d1 located in the through hole 9c1.

(4) Next, the injection molding of the thermoplastic resin material between the lid plate 7 and the battery case 5 using the mold 9 will be specifically described.
First, resin melted by a heater or the like was injected into the resin injection port 9c2 by the injection plunger 11, and flowed into the cavity 10 through the injection path 9d1. Polyphenylene sulfide (PPS) was used for this thermoplastic resin material.

  After filling the cavity 10 with a thermoplastic resin material poured, the injection plunger 11 is pushed toward the injection path 9d1 from the upper part of the resin injection port 9c2, and the resin is subjected to surface treatment by applying pressure. The battery case 5 was brought into close contact with the inner surface 5 a of the opening and the end surface 7 a of the lid plate 7. Then, after the thermoplastic resin material is cooled and hardened in the mold 9, the movable lower mold 9 b is removed downward from the lower mounting plate 9 a side, the mold 9 is opened, and the battery case 5 is removed. As shown, a molded product in which the lid plate 7 was integrally joined to the opening of the battery case was completed.

  As described above, since the fine recesses are surface-treated in advance by the above-mentioned pretreatment on the inner peripheral surface 5a of the opening of the battery case 5 and the outer peripheral surface 7a of the lid plate 7, the surface is treated. The thermoplastic resin melted by molding flows into the mold, and is further applied to the thermoplastic resin by injection pressure, so that the resin is brought into intimate contact between the inner peripheral surface 5a of the opening and the outer peripheral surface 7a of the lid plate 7. It becomes a state. An effective adhesion performance with a high degree of adhesion with the thermoplastic resin is obtained between the inner circumferential surface 5 a of the opening and the outer circumferential surface 7 a of the lid plate 7, and the battery case 5 and the lid plate 7 are firmly joined. It was possible.

(5) Finally, after the lid plate 7 and the battery case 5 are welded via the resin, a current collector plate connected to the negative electrode side electrode of the power generation element is welded to the lid plate 7 to form the positive electrode side aluminum. The made lid plate 8 was fitted into one end opening of the battery case 5 and laser welded. Thus, the battery of Example 1 was completed.

(Comparative Example 1)
As Comparative Example 1, a battery in which the cover plate did not have a portion smaller than the inner dimension of the battery case was manufactured. Specifically, the cover plate was made equal to the outer size of the battery case. In this case, the welding method between the battery case and the cover plate and other methods for manufacturing the battery were the same as those in Example 1.

(Battery evaluation method and results)
About each of the battery of Example 1 and Comparative Example 1, it fixed to the vibration testing machine so that a vibration might be transmitted directly, and the vibration test was done. The condition is a vibration test in which a maximum of 2 G is applied in the vertical and horizontal directions, and the test time is 24 hours in total. After that, it was left for 30 days in a temperature environment of 80 ° C. Finally, the change in mass of the battery of Example 1 and the battery of Comparative Example 1 before and after the test was evaluated.

  As a result, in the battery of Comparative Example 1, a mass reduction of about 30 mg was observed, but in the battery of Example 1, no mass reduction was observed. Therefore, in the battery of Example 1, it was confirmed that good airtightness was secured. In other words, it was found that the battery of Example 1 in which the invention of the present application was implemented ensured vibration shock resistance, insulation, and airtightness. Probably because of improved resistance to vibration in the left-right direction.

(About other embodiments)
Although the case where the cross-sectional shape is a concave cover plate is shown in the first embodiment, the cover plate considering the connection with the adjacent battery in order to use these batteries as an assembled battery assuming the case of in-vehicle use. It can also be shaped. For example, a flange portion may be provided on the lid plate, and the flange portion 7b and the positive electrode side lid plate of the adjacent battery may be fixed by welding such as laser welding or TIG welding. For reference, FIG. 5 shows an overall view in which two non-aqueous electrolyte secondary batteries of the present invention are connected in series.

  In the above, although this invention was demonstrated according to Example 1 which concerns on embodiment, the range specified by this invention is not limited to the above-mentioned Example, In the range which does not deviate from the summary, it is suitably Needless to say, it can be changed and applied.

It is a perspective view which shows the general view of the conventional nonaqueous electrolyte secondary battery. It is sectional drawing of two types of nonaqueous electrolyte secondary batteries which concern on the aspect which implements this invention. It is a partially broken perspective view of the nonaqueous electrolyte secondary battery in the Example of this invention. It is sectional drawing which shows the injection molding mold of the thermoplastic material provided by injection molding between a battery case and a cover plate, and the integral molding process of a battery case, a cover plate, and a thermoplastic material. It is the whole figure by which the two nonaqueous electrolyte secondary batteries in the Example of this invention were connected in series, and the enlarged view of the connection part.

DESCRIPTION OF SYMBOLS 1 Battery case 2 Lid 3a Positive electrode terminal 3b Negative electrode terminal 4 Resin packing 5 Battery case 5a Battery case opening inner peripheral surface 5b Battery case opening upper surface 6 Thermoplastic resin material 7 Negative electrode cover plate 7a Lid plate outer peripheral surface 7b Adjacent battery Flange portion for connection 8 positive cover plate 9 injection molding die 9a lower mounting plate 9b movable lower die 9c upper mounting plate 9c1 through hole 9c2 resin injection port 9d fixed upper die 9d1 injection path 10 cavity portion

  The present invention relates to a battery including a battery case having an opening and a lid plate fitted to the opening.

  As portable devices such as mobile phones are rapidly spreading, high performance secondary batteries have been required as their power source. As such a secondary battery, a non-aqueous electrolyte secondary battery using a substance capable of inserting and extracting lithium ions as a positive electrode and a negative electrode material has been developed and put into practical use.

  In recent years, the non-aqueous electrolyte secondary battery has been used for a wide range of applications such as power assist bicycles and hybrid electric vehicles as well as portable devices. In such a case, since the use environment of the battery is different from that of the portable device, the structure of the non-aqueous electrolyte secondary battery is particularly problematic. Therefore, a sealed battery structure in which a power generation element including a positive electrode and a negative electrode, which is conventionally known, is housed in a battery container will be described.

In the coin-type battery of Patent Document 1, a lead terminal is configured from an electric insulating material such as resin packing from a cover plate, while a battery case having an opening is configured from a bottomed cylindrical body made of metal such as aluminum. Then, the opening is closed with a lid plate, and both are hermetically joined by caulking or laser welding to prevent leakage of the electrolyte, and at the same time, prevent the entry of water and air from the outside of the non-aqueous electrolyte secondary battery. It tries to prevent deterioration.
In the battery of Patent Document 2, the positive electrode end face electrode and the negative electrode end face electrode of the stacked power generation element are electrically connected to the positive electrode terminal and the negative electrode terminal by a conductive adhesive, and the battery case opening and the metal The lid plate is sealed with two types of adhesives, and the sealing between the terminals and the insulation is ensured.

In addition, the form of the sealed battery in which the caulking structure is adopted in the terminal structure is disclosed in FIG.
JP 2005-71649 A JP 2004-179090 A

  However, in the battery disclosed in Patent Document 1, the compressive stress of the resin gasket is used in order to ensure hermeticity. When force is applied to the caulking portion with respect to external force, the bonding force is stably maintained. In addition to this, there is a problem that the caulking force may be weakened due to deterioration of the gasket due to heat cycle over a long period of time, and as a result, a decrease in the airtightness of the battery is inevitable.

  Moreover, in patent document 2, when using two types of adhesive bond layers in order to ensure insulation and airtightness without using the said resin gasket, as disclosed in this patent document 2 When the structure is adopted, there is a problem that various vibrations generated when the battery is mounted on a vehicle such as an automobile (for example, a hybrid electric vehicle) cannot avoid adversely affecting the sealing performance. In addition, since one type of the adhesive layer has electrical conductivity, that is, when a large current charge / discharge is performed for an application such as a hybrid vehicle, heat is generated due to the resistance unique to the adhesive layer. As a result, there was a problem that the adhesive layer was deteriorated and the adhesive strength was lowered.

On the other hand, when a battery is mounted on a hybrid electric vehicle or the like, a compact configuration has been studied.

The present invention intends to provide a battery having a compact configuration when the battery is mounted on a hybrid electric vehicle or the like.

  The present invention made in view of the above problems will be described below.

The battery according to the present invention is a battery case having an opening, a lid plate fitted into the opening, a thermoplastic material disposed between the battery case and the lid plate, and the battery case And a thermoplastic material that bonds the lid plate to each other, and the thermoplastic material does not protrude from a side end portion of the battery case and an upper end portion of the lid plate.

According to the battery according to the present invention, when the battery is mounted on a hybrid electric vehicle or the like, a compact configuration can be achieved.

(Outline of the present invention)
  First, the outline of the battery according to the present invention will be described.

The battery according to the present invention is a battery case having an opening, a lid plate fitted to the opening, a thermoplastic material disposed between the battery case and the lid plate, and the battery case And a thermoplastic material that bonds the lid plate to each other, and the thermoplastic material is a battery that does not protrude from a side end portion of the battery case and an upper end portion of the lid plate.

In this case, the lid plate includes a portion smaller than the inner dimension of the opening in a portion that fits with the battery case, and a thermoplastic material is disposed between the lid plate and the battery case, thereby The lid plate and the battery case may be bonded .

As a specific aspect of the present invention, for example, an aspect as shown in FIG. 2 (a) or (b) of the present application may be used . In addition, the cover plate of Fig.2 (a) is concave shape. The concave shape means a shape composed of a flat plate and a plate protruding in a direction substantially perpendicular to the peripheral edge of the flat plate, but does not require geometric precision.

When a battery to which this aspect is applied is mounted on a vehicle, the vibration resistance against vibrations in the horizontal direction in FIG. 2 is improved, and the sealing strength can be maintained.

The thermoplastic material referred to in the present application is a resin material that has excellent sealing properties and high bonding strength with respect to metal materials, and is excellent in heat resistance, chemical resistance, and electrical insulation during normal use. As thermoplastic material, it may be I der those provided by injection molding.

  A metal can be used for the battery case of the present invention, and the same metal as the battery case or a different metal can be used for the cover plate.

As another aspect of the present invention, the lid plate is smaller than the inner dimension of the opening of the battery case, and a thermoplastic material is disposed between the battery case, the lid plate, and the battery case. The lid plate and the battery case may be bonded together.
In this case , for example, there is an embodiment as shown in FIG.

Furthermore, in this application, you may comprise a cover plate from one metal material or one clad material . By using one metal material or one clad material and using it as a terminal, the cost required for manufacturing the battery can be greatly reduced. Furthermore, the shape of the battery is extremely simple, and a battery having no protruding portion can be formed. Therefore, when mounting the battery according to the present invention on a hybrid electric vehicle or the like, a compact configuration can be achieved, and high discharge performance can be exhibited.

  The lid plate shape can be a simple plate shape or a concave shape. However, if the welding area with the thermoplastic resin material is widened, the adhesion strength and airtightness can be secured, the flange for the battery assembly can be easily provided at a low cost, and the cover plate can be made lightweight. Considering what can be done, the concave shape is good.

  Furthermore, the cover plate can be configured such that any part of the cover plate itself exhibits either the positive or negative polarity. The same applies to the battery case. Then, the battery case has a function of becoming a terminal, and the lid plate has a function of becoming a terminal.

In still another aspect of the present invention, the battery case has a positive polarity and the lid plate has a negative polarity, or the battery case has a negative polarity and the lid plate has a positive polarity. may I Oh.

  The battery case and the cover plate are electrically connected to the positive electrode or the negative electrode of the power generation element inserted into the battery case, respectively, so that polarity is imparted to the battery case and the cover plate.

Further, as another aspect of the present invention, the portion of which the thermoplastic material of the surface of the surface and / or the cover plate of the battery case is disposed, it may be surface treated is.

In this case, the surface treatment is for improving the adhesion between the battery case and the thermoplastic material. Specifically, it means that fine irregularities are provided in a portion of the surface of the battery case and / or the surface of the lid plate where the thermoplastic material is disposed. Thereby, an anchor effect is exhibited and the adhesiveness of the metal and thermoplastic material which comprise a battery case or a cover board becomes favorable.

Further, as another aspect of the present invention, a metal battery case that also functions as a terminal having electrical polarity and having an opening at one end thereof, and a function of a terminal having a polarity different from that of the battery case the doubles, and a battery and a metal cover plate for the inner surface and the fitting of the opening, also the gap between the battery case and the lid plate are hermetically bonded sealing thermoplastic material Good .

In this case, there is injection molding as a method of arranging the thermoplastic material.

According to the battery of the specific embodiment of the present invention , the reliability of the long life is high without using the compressive stress of the resin component for obtaining vibration shock resistance, insulation and airtightness, and the terminal component. Therefore, it is possible to provide a low-cost non-aqueous electrolyte secondary battery with a small number of parts. Therefore, the battery according to the specific embodiment of the present invention is particularly suitable for in-vehicle applications such as for hybrid electric vehicles.

  The best embodiment of the present invention will be described with reference to FIGS.

Example 1
Embodiments of the present invention will be described with reference to the drawings. In these drawings, the same reference numerals are given to constituent members having functions similar to those of the conventional example shown in FIG.

(1) A prismatic nonaqueous electrolyte secondary battery according to Example 1 of the present invention will be described below as an example. Since the fracture | rupture perspective view of the nonaqueous electrolyte secondary battery which concerns on Example 1 was shown in FIG. 3, when this is referred, it will be easy to grasp | ascertain the structure first.

  In the battery of this Example 1, as shown in FIG. 2 (a), a thermoplastic material 6 having non-aqueous electrolyte resistance is melted in one end opening portion of a metal rectangular battery case 5. The metal lid plate 7 is sealed and welded by pouring and cooling.

  The lid plate 7 has a plate shape here, but may have a pan lid shape as shown in FIG. The battery case contains a power generation element (not shown) and is filled with a non-aqueous electrolyte. The power generation element is obtained by winding a positive electrode and a negative electrode in a long cylindrical shape through a separator, and these positive electrode and negative electrode are connected to a current collector plate (not shown).

Here, in FIG. 2A, when the upper surface 5 b side of the opening of the battery case 5 is the upper side, the thermoplastic material 6 has a shape that does not protrude from the uppermost portion (upper end portion) of the lid plate 7. It is disclosed that it is arranged. Further, the thermoplastic material 6 has a shape that does not protrude from the outer side surface (side end portion) of the battery case 5. 2B also discloses that the thermoplastic material 6 is arranged in a shape that does not protrude from the uppermost portion of the lid plate 7 and the outer side surface of the battery case 5. Yes.

Since Example 1 shows a non-aqueous electrolyte secondary battery, the metal component on the positive electrode side is made of aluminum or an aluminum alloy that does not dissolve in the non-aqueous electrolyte in the positive electrode battery, and the metal component on the negative electrode side is negative electrode active. Copper or a copper alloy that is not alloyed with the material, nickel-copper clad material, or the like is used.
Accordingly, here, the battery case 5 and the cover plate 8 serving as the battery case are made of aluminum so as to be on the positive electrode side, and the nickel-copper clad material is used for the cover plate 7 serving as the negative electrode side.

(2) Next, the surface treatment for the part where the battery case comes into contact with the thermoplastic resin material will be described.
As a surface treatment method of the aluminum alloy which is the battery case 5, there is an “aqueous solution immersion method” in which the aluminum alloy is immersed in an aqueous solution. In this embodiment, after the aluminum is immersed in an aqueous solution of ammonia (NH 3), it is washed with water and dried. Adopted. As a result, the aluminum surface became an etched surface in which ultrafine recesses were formed.

  On the other hand, as a surface treatment method for copper, which is the cover plate 7 also serving as the negative electrode terminal, the copper surface is brought into contact with an aqueous solution containing an azole compound and an organic acid, and after forming a thick film of the azole compound on the copper surface, further microetching is performed. The surface was submerged by the method, and the adhesion to the resin was remarkably improved.

(3) A method for integrally forming the battery case 5 and the lid plate 7 that also serves as the negative electrode terminal may be simply described because a known method may be used. As shown in FIG. 4, an injection mold (hereinafter referred to as a mold) 9 formed of a metal having excellent heat resistance for forming a thermoplastic material between the lid plate 7 and the cylindrical battery case 5 is as follows. A movable lower mold 9b was provided on the upper surface of the lower mounting plate 9a, and a cylindrical cylindrical battery case 5 was previously installed inside. The movable lower mold 9b was inserted so that the center part fits in the battery case 5.

  A fixed upper die 9 d was provided on the lower surface of the upper mounting plate 9 c and placed so as to be in close contact with the upper surface 5 b of the opening of the battery case 5 and the upper surface of the lid plate 7. A cavity 10 is formed on the lower surface of the fixed upper mold 9d, and the cavity 10 is formed into a square cavity by the lower surface of the fixed upper mold 9d, the inner surface 5a of the battery case 5, and the lid plate side surface 7a.

  The rectangular hollow portion 10 is formed with an injection passage 9d1 penetrating vertically in a part of the ceiling, and a through hole 9c1 penetrating vertically at the same position of the upper mounting plate 9c overlapping the upper opening of the injection passage 9d1. A resin injection port 9c2 is formed at the upper end of the injection path 9d1 located in the through hole 9c1.

(4) Next, the injection molding of the thermoplastic resin material between the lid plate 7 and the battery case 5 using the mold 9 will be specifically described.
First, resin melted by a heater or the like was injected into the resin injection port 9c2 by the injection plunger 11, and flowed into the cavity 10 through the injection path 9d1. Polyphenylene sulfide (PPS) was used for this thermoplastic resin material.

  After filling the cavity 10 with a thermoplastic resin material poured, the injection plunger 11 is pushed toward the injection path 9d1 from the upper part of the resin injection port 9c2, and the resin is subjected to surface treatment by applying pressure. The battery case 5 was brought into close contact with the inner surface 5 a of the opening and the end surface 7 a of the lid plate 7. Then, after the thermoplastic resin material is cooled and hardened in the mold 9, the movable lower mold 9 b is removed downward from the lower mounting plate 9 a side, the mold 9 is opened, and the battery case 5 is removed. As shown, a molded product in which the lid plate 7 was integrally joined to the opening of the battery case was completed.

  As described above, since the fine recesses are surface-treated in advance by the above-mentioned pretreatment on the inner peripheral surface 5a of the opening of the battery case 5 and the outer peripheral surface 7a of the lid plate 7, the surface is treated. The thermoplastic resin melted by molding flows into the mold, and is further applied to the thermoplastic resin by injection pressure, so that the resin is brought into intimate contact between the inner peripheral surface 5a of the opening and the outer peripheral surface 7a of the lid plate 7. It becomes a state. An effective adhesion performance with a high degree of adhesion with the thermoplastic resin is obtained between the inner circumferential surface 5 a of the opening and the outer circumferential surface 7 a of the lid plate 7, and the battery case 5 and the lid plate 7 are firmly joined. It was possible.

(5) Finally, after the lid plate 7 and the battery case 5 are welded via the resin, a current collector plate connected to the negative electrode side electrode of the power generation element is welded to the lid plate 7 to form the positive electrode side aluminum. The made lid plate 8 was fitted into one end opening of the battery case 5 and laser welded. Thus, the battery of Example 1 was completed.

( Example 2 )
As Example 2 , a battery in which the cover plate did not have a portion smaller than the inner dimension of the battery case was manufactured. Specifically, the cover plate was made equal to the outer size of the battery case. In this case, the welding method between the battery case and the cover plate and other methods for manufacturing the battery were the same as those in Example 1.

(Battery evaluation method and results)
About each of the battery of Example 1 and Example 2 , it fixed to the vibration testing machine so that a vibration might be transmitted directly, and the vibration test was done. The condition is a vibration test in which a maximum of 2 G is applied in the vertical and horizontal directions, and the test time is 24 hours in total. After that, it was left for 30 days in a temperature environment of 80 ° C. Finally, the mass change of the battery of Example 1 and the battery of Example 2 before and after the test was evaluated.

As a result, in the battery of Example 2 , a mass reduction of about 30 mg was observed, but in the battery of Example 1, no mass reduction was observed. Therefore, in the battery of Example 1, it was confirmed that good airtightness was secured. In other words, it was found that the battery of Example 1 in which the invention of the present application was implemented ensured vibration shock resistance, insulation, and airtightness. Probably because of improved resistance to vibration in the left-right direction.

(About other embodiments)
Although the case where the cross-sectional shape is a concave cover plate is shown in the first embodiment, the cover plate considering the connection with the adjacent battery in order to use these batteries as an assembled battery assuming the case of in-vehicle use. It can also be shaped. For example, a flange portion may be provided on the lid plate, and the flange portion 7b and the positive electrode side lid plate of the adjacent battery may be fixed by welding such as laser welding or TIG welding. For reference, FIG. 5 shows an overall view in which two non-aqueous electrolyte secondary batteries of the present invention are connected in series.

  In the above, although this invention was demonstrated according to Example 1 which concerns on embodiment, the range specified by this invention is not limited to the above-mentioned Example, In the range which does not deviate from the summary, it is suitably Needless to say, it can be changed and applied.

It is a perspective view which shows the general view of the conventional nonaqueous electrolyte secondary battery. It is sectional drawing of two types of nonaqueous electrolyte secondary batteries which concern on the aspect which implements this invention. It is a partially broken perspective view of the nonaqueous electrolyte secondary battery in the Example of this invention. It is sectional drawing which shows the injection molding mold of the thermoplastic material provided by injection molding between a battery case and a cover plate, and the integral molding process of a battery case, a cover plate, and a thermoplastic material. It is the whole figure by which the two nonaqueous electrolyte secondary batteries in the Example of this invention were connected in series, and the enlarged view of the connection part.

DESCRIPTION OF SYMBOLS 1 Battery case 2 Lid 3a Positive electrode terminal 3b Negative electrode terminal 4 Resin packing 5 Battery case 5a Battery case opening inner peripheral surface 5b Battery case opening upper surface 6 Thermoplastic resin material 7 Negative electrode cover plate 7a Lid plate outer peripheral surface 7b Adjacent battery Flange portion for connection 8 positive cover plate 9 injection molding die 9a lower mounting plate 9b movable lower die 9c upper mounting plate 9c1 through hole 9c2 resin injection port 9d fixed upper die 9d1 injection path 10 cavity portion

Claims (2)

A battery case having an opening, and a cover plate fitted to the opening;
The lid plate includes a portion smaller than the inner dimension of the opening in a portion that fits with the battery case,
The lid plate and the battery case are bonded by arranging a thermoplastic material between the lid plate and the battery case,
The battery characterized in that the battery case has a positive polarity and the lid plate has a negative polarity, or the battery case has a negative polarity and the lid plate has a positive polarity. A battery case made of metal that serves as a terminal having electrical polarity and has an opening at one end;
A battery having a function of a terminal having a polarity different from that of the battery case, and having a metal lid plate fitted to the inner surface of the opening,
A battery characterized in that a gap between the battery case and the lid plate is adhesively sealed with a thermoplastic material.