JPWO2013018396A1 - Sealing terminal and battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing terminal with a relatively small electric leakage. A sealing plate 12 having a sealing plate through hole 12a penetrating between one main surface 12α and the other main surface 12β, a first surface 16α joined to the one main surface 12α, and a first surface. The ceramic body 16 including the second surface 16β opposite to 16α and the ceramic body through-hole 16a, the ceramic body through-hole 16a and the sealing plate through-hole 12a are inserted into the ceramic body through-hole 16a. And a terminal body 14 including a flange portion 19 having a flat surface portion 19β joined to the second surface 16β so as to face the second surface 16β. The ceramic body 16 penetrates the ceramic body. The opening of the hole 16a is larger on the first surface 16α side than the second surface 16β side, and the inner peripheral surface of the sealing plate through hole 12a is located in the outer region of the opening on the first surface 16α side. is doing.

Description

  The present invention relates to a sealing terminal that is attached to an electrolytic solution container such as a lithium ion battery and takes out electricity while sealing the electrolytic solution container, and a battery using the sealing terminal.

  For example, a lithium ion battery or the like uses a sealing terminal for taking out electricity to the outside while sealing a battery body containing an electrolytic solution inside. For example, Patent Document 1 below describes an example of a conventional sealing terminal. Such a sealing terminal 100 described in Patent Document 1 includes a sealing plate 102 made of a metal having a through hole 102a and a through hole 104a, as shown in cross-sectional views in FIGS. 5 (a) and 5 (b). A cylindrical ceramic body 104 and a terminal body 106 inserted through the through hole 102a and the through hole 104a are provided. The terminal body 106 includes a columnar portion 107 and a flange portion 108 protruding from the columnar portion 107, and the sealing plate 102 and the ceramic body 104 are bonded to each other via the bonding layer 110. The ceramic body 104 is bonded via the bonding layer 112. In Patent Document 1, the bonding layer 110 and the bonding layer 112 are manufactured through a low-temperature process such as a cold spray method.

JP 2009-54966 A

  In the ceramic body 104 described in Patent Document 1, the diameter of the through-hole 104 is substantially from the first surface on the upper side in FIG. 5A toward the second surface on the lower side in FIG. It is assumed to be constant. In such a conventional sealed terminal, it has been difficult to completely suppress defects such as liquid leakage accompanying damage to the terminal body 106 and defects in the bonding layer. For example, as shown in FIG. 5A, when the diameter of the through-hole 104a of the ceramic body 104 is larger than the outer diameter of the columnar portion 107 of the terminal body 106, the flange portion 108 is heated as the temperature changes. When expanded or thermally contracted, the angle or the like of the columnar portion 107 is easy to move (movement as indicated by the arrow in FIG. 5A), and the inner peripheral surface of the through hole 104a of the ceramic body 104 and the terminal body 106 are connected. The terminal body 106 may be damaged by contact. In addition, when the bonding body 110 and the terminal body 106 are too close to each other due to a change in the posture of the terminal body 106, an electrical failure such as a current flowing between the terminal body 106 and the bonding layer 110 occurs. There was also. As shown in FIG. 5B, when the outer diameter of the columnar portion 107 of the terminal body 106 and the through hole 104a of the ceramic body 104 are approximately the same size, the ceramic body is expanded by the expansion of the terminal body 106. There is a problem that breakage of 104 occurs or current easily flows between the terminal body 106 and the bonding layer 110 through the surface of the ceramic body 104. The present invention aims to solve this problem.

  In order to solve the above problems, the present invention provides a sealing plate through hole penetrating between one main surface, the other main surface opposite to the one main surface, and between the one main surface and the other main surface. A first plate joined to the one main surface of the sealing plate, a second surface opposite to the first surface, the first surface, and the first surface A ceramic body including a ceramic body through-hole connected to the sealing plate through-hole penetrating between the second surfaces; the ceramic body being inserted through the ceramic body through-hole and the sealing plate through-hole; and the ceramic An end portion on the side of the body through-hole is located outside the ceramic body through-hole, and the end portion has a flat portion joined to the second surface so as to face the second surface And the ceramic body has an opening of the ceramic body through-hole on the second surface side. A sealing terminal, wherein the sealing terminal is larger on the first surface side, and an inner peripheral surface of the sealing plate through hole is located in an outer region of the opening on the first surface side. provide.

  The sealing terminal, a container having the sealing terminal attached to the opening, and a battery body accommodated in the container and electrically connected to the terminal body of the sealing terminal. A battery characterized by the above is also provided.

  The sealed terminal of the present invention has a relatively small electrical leakage from the terminal body. The battery of the present invention has stable battery performance over a relatively long period of time, a relatively long life, and high reliability.

It is a figure explaining one Embodiment of the sealing terminal of this invention, (a) is a schematic top view, (b) is a schematic sectional drawing cut | disconnected by the AA 'line shown to (a), (c) is It is the schematic sectional drawing cut | disconnected by the BB 'line | wire shown to (a). It is a figure explaining one Embodiment of the battery of this invention comprised including the sealing terminal shown in FIG. 1, (a) is a schematic perspective view, (b) is a schematic sectional drawing. It is a schematic sectional drawing of the battery main-body part with which the battery shown in FIG. 2 is provided. (A) And (b) is a schematic sectional drawing explaining other embodiment of the sealing terminal of this invention, respectively. (A) And (b) is a schematic sectional drawing of an example of the conventional sealing terminal.

  Embodiments of the sealed terminal and battery of the present invention will be described in detail below.

  First, with reference to FIG. 1, the sealing terminal 10 which is one Embodiment of the sealing terminal of this invention is demonstrated. The sealing terminal 10 is arranged in a sealing plate 12 having a metal as a main component and a sealing plate through hole 12a provided in the sealing plate 12, and receives power from a battery body configured to contain an electrolytic solution. The terminal body 14 is fixed to the sealing plate 12 in a state where the sealing body 12 and the terminal body 14 that are joined to both the terminal body 14 to be taken out and the sealing plate 12 and the terminal body 14 are insulated. And a ceramic body 16. The ceramic body 16 includes a ceramic body through hole 16a (hereinafter also referred to as a through hole 16a), and the terminal body 14 is fixed in a state of being inserted through the through hole 16a. In the present embodiment, the sealing plate 12 is provided with two sealing plate through-holes 12a (hereinafter also referred to as through-holes 12a), and the ceramic body 16 and the terminal body 14 are provided for each of these through-holes 12a. Is provided. In the example shown in FIG. 1B and FIG. 1C, each of the configurations around the through hole 12a is shown as a representative, but the peripheral portion of the other through hole 12a is similar. It has a configuration. In addition, the number of the terminal bodies in a sealing terminal is not specifically limited. The inner diameter of the through hole 12a is, for example, about 10 mm to 20 mm.

  When the sealing plate 12 constitutes a battery 60 as shown in FIG. 2 to be described later, the one main surface 12α on the side where the battery body 61 containing the electrolytic solution is disposed and the side opposite to the one main surface 12α. The other main surface 12β and a through hole 12a (sealing plate through hole 12a) penetrating between the one main surface 12α and the other main surface 12β. The sealing plate 12 is preferably made of, for example, an Al alloy (for example, JIS H 4040 alloy number 3003) that has excellent corrosion resistance with respect to an electrolytic solution containing lithium ions and is easy to braze.

  Further, the sealing plate 12 includes a stepped portion 15 that is recessed when viewed from the one main surface 12α side and a recessed portion 13 that is continuous with the stepped portion 15 around the through hole 12a. As shown in FIG. 1A, the recess 13 is provided so as to protrude from the peripheral edge of the central recess 21 in a top view and a substantially circular central recess 21 in a top view, corresponding to the shape of the ceramic body 16. A plurality of peripheral recesses 23 are provided. In the present embodiment, the thickness of the sealing plate 12 is substantially constant without different between the region corresponding to the recess 13 and other regions, and the thickness is about 3 mm to 7 mm. .

  The ceramic body 16 includes a first plate 16α, a second surface 16β opposite to the first surface 16α, and a sealing plate penetrating between the first surface 16α and the second surface 16β. And a ceramic body through hole 16a connected to the through hole 12a. The first surface 16α of the ceramic body 16 is bonded to a region corresponding to the recess 13 in the one main surface 12α via a bonding layer 32 described later. More specifically, the first surface 16α of the ceramic body 16 is bonded to the region corresponding to the bottom surface of the concave portion 13 on the one main surface 12α via the bonding layer 32.

  The terminal body 14 is inserted through the through-hole 16a and the through-hole 12a, and the lower end in the figure is located outside the through-hole 16a (below the through-hole 16a). The terminal body 14 includes a flange 19 at the outer end of the through hole 16a. The flange portion 19 includes a flat surface portion 19β facing the second surface 16β of the ceramic body 16, and the flat surface portion 19β is bonded to the second surface 16β of the ceramic body 16 via a bonding layer 34 described later. ing. The flange portion 19 has a thin wall portion 19t whose thickness gradually decreases as the distance from the central axis of the through hole 16a increases. In the terminal body 14, the maximum diameter of the flange portion 19 is approximately 15 to 30 mm, and the diameter of the columnar portion other than the flange portion 19 is, for example, approximately 5 to 15 mm. The thickness of the ceramic body 16 is about 5 mm to 30 mm.

  The opening of the through hole 16a of the ceramic body 16 is larger in the opening on the first surface 16α side than the opening on the second surface 16β side, and from the second surface 16β of the ceramic body 16 The distance along the inner surface of the through hole 16a to the first surface 16α is relatively long. In addition, the inner peripheral surface of the through hole 12a (sealing plate through hole 12a) is located in the outer region of the opening on the first surface 16α side. That is, in this embodiment, the ceramic between the flange portion 19 of the terminal body 14 joined to the second surface 16β of the ceramic body 16 and the sealing plate 12 joined to the first surface 16α of the ceramic body 16 is used. A separation distance (so-called creepage distance) along the surface of the body 16 is relatively long. Thereby, the insulation between the terminal body 14 and the sealing board 12 is maintained with high certainty. The diameter of the opening on the second surface 16β side of the through hole 16a is approximately the same as the diameter of the columnar portion other than the flange portion 19 of the terminal body 14, and is, for example, 5 to 15 mm. The diameter of the opening on the first surface 16α side of the through hole 16 is slightly smaller than the diameter of the through hole 12a, for example, about 8 to 28 mm.

  Further, in the ceramic body 16, the cross-sectional area of the through hole 16a is constant from the second surface 16β side to the first surface 16α side, and the remaining portion is on the second surface 16β side. To the first surface 16α side. In a portion where the cross-sectional area of the through-hole 16a is constant, the position of the terminal body 14 is defined with high accuracy by the inner peripheral surface of the through-hole 16a. . In addition, since the cross-sectional area of the through hole 16a increases from the second surface 16β side toward the first surface 16α side, the flange portion 19 of the terminal body 14 and the sealing plate 12 The creepage distance between is relatively large. Further, since the cross-sectional area of the through-hole 16a is increased toward the first surface 16α, the terminal body 14 is accompanied by a minute expansion or deformation of the terminal body 14 due to a surrounding temperature change or the like. The contact of the body 14 with the ceramic body 16 is suppressed, and deterioration of the terminal body due to a slight state change such as ambient temperature is suppressed.

When the ceramic body 16 is made of, for example, alumina ceramics, an organic binder suitable for a raw material powder such as aluminum oxide (alumina: Al ₂ O ₃ ), silicon oxide (SiO ₂ ), calcium oxide (CaO), magnesium oxide (MgO), or the like. The raw material powder prepared by adding is filled into a press mold of a predetermined shape, and this is pressed and molded at a predetermined pressure, and then the obtained molded body is fired at a temperature of about 1600 ° C. in the atmosphere. It can be manufactured by doing. As described above, in the ceramic body 16, the cross-sectional area of the through-hole 16a is constant until the middle, and the remaining portion becomes larger toward the first surface 16α, which is relatively easy by press molding, for example. Can be produced.

  The bonding between the ceramic body 16 and the sealing plate 12 and the bonding between the ceramic body 16 and the terminal body 14 will be described. The bonding layer 32 includes a metallized layer 42 made of, for example, Mo—Mn or the like, which is deposited on the first surface 16α of the ceramic body 16, and a brazing material layer 52 mainly composed of Al. For example, a metal paste obtained by adding and mixing an appropriate organic binder and solvent to Mo powder, Mn powder, and metal oxide powder is applied to the first surface 16α of the ceramic body 16, and this is applied to the metallized layer 42. It can be formed by baking at a temperature of about 1400 ° C. in a reducing atmosphere. The brazing material layer 52 is made of an Al alloy containing Al as a main component, and uses an Al—Si based brazing material. In addition, Al alloy has a strong oxide film on its surface, so its brazeability is relatively low, so it contains a small amount of magnesium (Mg) that has a getter action to remove the oxide film on the Al alloy surface and improve brazeability. It is preferable to use what was done. The ceramic body 16 is bonded so that the first surface 16α faces the bottom surface of the central recess 21 of the sealing plate 12. When the bonding layer 32 is formed, the ceramic body 16 is positioned by the step portion 15 between the central recess 21 and the periphery thereof, and the ceramic body 16 is bonded to a predetermined position with respect to the sealing plate 12 with high positional accuracy. ing.

  In order to make the bonding between the ceramic body 16 and the sealing plate 12 relatively strong, it is preferable to supply as much brazing material layer 52 as possible in the gap between the ceramic body 16 and the sealing plate 12. On the other hand, when the amount of brazing material constituting the brazing material layer 52 is excessive, for example, when the brazing material protrudes to the second surface 16β side of the ceramic body 16, the space between the sealing plate 12 and the terminal body 14 is increased. Current (surface leakage current, etc.) easily flows. In this embodiment, the recess 13 includes a plurality of peripheral recesses 23, and the brazing material layer 52 that overflows from the gap between the ceramic body 16 and the sealing plate 12 is formed as shown in FIG. The peripheral recess 23 is accommodated. In this embodiment, the leakage of the brazing material layer 52 and the leakage of current between the sealing plate 12 and the terminal body 14 due to the protrusion are suppressed. From the viewpoint of ease of positioning with the ceramic body, it is preferable to provide the recess 21, and it is preferable to provide the peripheral recess 23 from the viewpoint of suppressing the excess brazing material from protruding.

  The bonding layer 34 includes a metallized layer 44 made of, for example, Mo—Mn or the like, which is deposited on the second surface 16β of the ceramic body 16, and a brazing material layer 54 mainly composed of Al. Similarly to the metallized layer 42, the metallized layer 44 is made of, for example, a metal paste obtained by adding and mixing an appropriate organic binder and solvent to Mo powder, Mn powder, and metal oxide powder, and the first surface 16α of the ceramic body 16. It can be formed by baking at a temperature of about 1400 ° C. in a reducing atmosphere. Similarly to the brazing material layer 52, the brazing material layer 54 is made of an Al alloy containing Al as a main component and uses an Al—Si based composition.

  In the present embodiment, the flange portion 19 includes a thin portion 19t whose thickness gradually decreases as it moves away from the central axis of the through hole 16a (ceramic through hole 16), and the thin portion 19t is relatively easily deformed. In the present embodiment, the thin-walled portion 19t is deformed, so that residual stress at the time of forming the bonding layer 34 due to, for example, a difference in thermal expansion between the ceramic body 16 and the terminal body 16 is released, and the bonding layer 34 In addition, damage to the ceramic body 16 itself is suppressed. In the bonding layer 32, it is preferable to provide a plating layer mainly composed of nickel, for example, in the gap between the metallized layer 42 and the brazing material layer 52 in order to increase the bonding strength. Similarly, in the bonding layer 34, it is preferable to provide a plating layer mainly composed of nickel, for example, in the gap between the metallized layer 44 and the brazing material layer 54 in order to increase the bonding strength.

  The material constituting the sealing terminal 10 and the material of the bonding layer are not particularly limited, but are described in the present embodiment in that high resistance is ensured against an electrolytic solution containing highly corrosive lithium ions. It is preferable to use various materials.

  Next, the battery 60 provided with the sealing terminal 10 will be described. As shown in FIG. 2, the battery 60 includes a battery body 61, a long cylindrical metal container 62 in which the battery body 61 is housed, and the sealing terminal 10 shown in FIG. Yes. In the sealing terminal 10, the peripheral portion of the sealing plate 12 is welded to the opening end 62 a of the metal container 62.

  The battery body 61 includes a housing 70 provided with a positive electrode terminal body 72 and a negative electrode terminal body 73, and a battery body 80 accommodated in the housing 70. FIG. 3 is a schematic cross-sectional view of the battery body 80, showing a state seen from the upper side in FIG. The main body 80 includes a separator 79, and a positive electrode plate 77 and a negative electrode plate 78 that are disposed in close proximity to each other with the separator 79 interposed therebetween, and an electrolyte solution (not shown) is filled in the gap between the members. Yes. In this embodiment, as a structure in which the positive electrode plate 77 and the negative electrode plate 78 are stacked, a so-called overlapping structure shown in FIG. 3 is adopted. The overlapping structure of the positive electrode plate 77 and the negative electrode plate 78 may employ a so-called folding structure or a winding structure, and is not particularly limited. The positive electrode plate 77 and the negative electrode plate 78 are obtained by applying an active material to a current collector (electrode base material). The active material in the positive electrode plate 77 can be used without being limited to oxides of transition metals such as cobalt, manganese, nickel, chalcogen compounds, composite compounds thereof, and various additive elements. As the active material in the negative electrode plate 78, a carbonaceous material is preferably used, but a material containing an oxide of boron and tin is also used. The shape is usually granular, and the particle size is preferably 0.3 to 20 μm, more preferably 1 to 5 μm. It is also possible to use metallic lithium as the active material. In the case of metallic lithium, it may be granular or foil-like. The positive electrode plate 77 and the negative electrode plate 78 are made of an electrochemically stable metal. The positive electrode plate 77 is preferably made of aluminum, and the negative electrode plate 78 is preferably made of copper. The current collector can be used in any shape, such as foil, net, and expanded metal. The positive electrode terminal 72 provided on the housing 70 is a plate-like member formed of a metal such as aluminum and is connected to the positive electrode plate 7 of the battery main body 80 housed in the housing 70. The negative electrode terminal 73 is a plate-like member made of nickel, copper or the like, and is connected to the negative electrode plate 78 of the battery main body 80 accommodated in the housing 70. The connection between the positive electrode plate 77 and the positive electrode terminal 72 and the connection between the negative electrode plate 78 and the negative electrode terminal 78 include various connection forms such as welding. However, as long as the current can be efficiently extracted from the battery main body 80. There is no particular limitation.

  The sealing terminal 10 is disposed so as to close the open end 62a of the metal container 62 in which the battery body 61 is accommodated. Specifically, in the state where one sealing terminal 14 of the sealing terminal 10 contacts the positive electrode terminal 72 and the other sealing terminal 14 contacts the negative electrode terminal 73, the peripheral portion of the sealing plate 12 is The metal container 102 is welded and joined to the open end 102a.

  The battery 60 configured with the sealing terminal 10 has a relatively small electrical leakage from the terminal body 16. The battery 60 of the present invention has stable battery performance over a relatively long period of time, and has a relatively long life and high reliability. In addition, the structure of the battery 60 is not specifically limited, The sealing terminal 10 can be widely used for the battery of various structures.

  4 (a) and 4 (b) are schematic cross-sectional views illustrating another embodiment of the sealing terminal of the present invention. 4, the same reference numerals as those in FIG. 1 are used for the same configurations as those in FIG. In the embodiment shown in FIG. 4A, the through-hole 16a has a first portion 91 whose cross-sectional area perpendicular to the central axis of the through-hole 16a is substantially the same as the cross-sectional area of the portion other than the flange portion 19 of the terminal body 14. The second portion 92 has a larger cross-sectional area than the first portion 92. Also in this embodiment, the opening of the through hole 16a of the ceramic body 16 is larger in the opening on the first surface 16α side than the opening on the second surface 16β side, The creepage distance between the ceramic body 16 and the sealing plate 12 is relatively long. In the embodiment shown in FIG. 4B, the cross-sectional area of the through hole 16a is gradually increased from the second surface 16β side to the first surface 16α side. Also in this case, the so-called creepage distance is relatively long. In the embodiment as shown in FIGS. 4A and 4B, the insulation between the terminal body 14 and the sealing plate 12 is maintained with high reliability.

  The sealing terminal and the battery of the present invention are not limited to the above-described embodiment and the above-described examples, and various improvements and modifications may be made without departing from the gist of the present invention. is there.

DESCRIPTION OF SYMBOLS 10 Sealing terminal 12 Sealing plate 12a Sealing plate through-hole 12 (alpha) One main surface 12 (beta) The other main surface 13 Recessed part 14 Terminal body 16 Ceramic body 16a Ceramic body through-hole 16 (alpha) 1st surface 16 (beta) 2nd surface 19 ridge part 19 (beta) Part 21 Central recess 23 Peripheral recess 32, 34 Bonding layer 42, 44 Metallized layer 52, 54 Brazing material layer 60 Battery 61 Battery body 62 Metal container 62a Open end 70 Housing 72 Positive electrode terminal body 73 Negative electrode terminal body 77 Positive electrode plate 78 Negative electrode Plate 79 Separator 80 Battery body 100 Sealing terminal 102 Sealing plate 102a Through-hole 104 Ceramic body 104a Through-hole 106 Terminal body 107 Columnar portion 108 Hook 110, 112 Bonding layer

Claims (9)

A sealing plate comprising one main surface, the other main surface opposite to the one main surface, and a sealing plate through-hole penetrating between the one main surface and the other main surface;
A first surface joined to the one main surface of the sealing plate, a second surface opposite to the first surface, and a space between the first surface and the second surface. A ceramic body provided with a ceramic body through hole connected to the sealing plate through hole;
The ceramic body through-hole and the sealing plate through-hole are inserted, and the end on the ceramic body through-hole side is located outside the ceramic body through-hole. A terminal body provided with a flange having a flat surface portion that is bonded to the second surface opposite to the surface of 2;
In the ceramic body, the opening of the ceramic body through-hole is larger on the first surface side than the second surface side, and the sealing is provided in an outer region of the opening on the first surface side. A sealing terminal in which an inner peripheral surface of a plate through hole is located.   A cross-sectional area of the ceramic body through hole is constant from the second surface side toward the first surface side, and the first portion from the second surface side in the remaining portion. The sealing terminal according to claim 1, wherein the sealing terminal increases toward the surface side. The sealing plate includes a recess around the sealing plate through-hole on the one main surface,
The sealing terminal according to claim 1, wherein the first surface of the ceramic body is joined to a region corresponding to a bottom surface of the concave portion.   The sealing terminal according to any one of claims 1 to 3, wherein a thickness of the flange portion gradually decreases as the distance from the central axis of the ceramic body through hole increases.   The said ceramic body has aluminum oxide as a main component, and the said sealing board and the said terminal body have aluminum as a main component, The sealing terminal in any one of Claims 1-4 characterized by the above-mentioned.   The second surface of the ceramic body and the planar portion of the flange portion of the terminal body are joined via a metallized layer and a brazing material layer that are attached to the second surface. The sealing terminal according to any one of claims 1 to 5.   The sealing terminal according to claim 6, wherein the metallized layer contains Mo—Mn alloy as a main component, and the brazing material layer contains aluminum as a main component. The sealing terminal according to any one of claims 1 to 7,
A container having the sealing terminal attached to the opening;
A battery comprising: a battery body housed in the container and electrically connected to the terminal body of the sealing terminal.   9. The battery according to claim 8, wherein the electrolytic solution contains lithium ions.

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