Battery package and battery module

Abstract

This battery package comprises: a wiring board having a first recess portion; a lid body having a second recess portion; and a sealing material. The wiring board includes a first base portion having the bottom surface of the first recess portion and a first frame portion positioned at the outer edge of said bottom surface. The lid body includes a second base portion having the bottom surface of the second recess portion and a second frame portion positioned at the outer edge of said bottom surface. In a vertical cross-sectional view of the battery package, a value obtained by dividing the height of the storage space of a battery by the wall thickness of the battery package is 3 or more.

Description

Battery package and battery module

[0001] The present disclosure relates to a battery package and a battery module.

[0002] Patent Document 1 discloses an electric double layer capacitor having a container for housing a battery element, the container for housing the battery element including a recessed container and a sealing plate.

[0003] Japanese Patent Application Publication No. 2001-216952

[0004] A battery package according to one embodiment of the present disclosure is a battery package for accommodating a battery, comprising: a wiring board having a first recess that forms a portion of an accommodating space for accommodating the battery; a lid body having a second recess that forms another portion of the accommodating space; and a sealing material that joins the wiring board and the lid body; the wiring board has an insulating base including a first base having a first surface that is the bottom surface of the first recess, and a first frame portion located on the outer edge of the first surface and defining the inner wall of the first recess; the lid body includes a second base having a third surface that is the bottom surface of the second recess, and a second frame portion located on the outer edge of the third surface and defining the inner wall of the second recess; and in a vertical cross-sectional view, the value obtained by dividing the height of the accommodating space by the wall thickness of the battery package is 3 or more.

[0005] A battery module according to one aspect of the present disclosure includes the battery package having a plurality of connection electrodes on the inner surface of the first recess, a battery having a positive electrode and a negative electrode, and a metal sinter material that joins the positive electrode and negative electrode of the battery to the corresponding connection electrodes.

[0006] A battery module according to one aspect of the present disclosure includes the battery package having a plurality of connection electrodes on the inner surface of the first recess, a battery having a positive electrode and a negative electrode, and an elastic member that presses the positive electrode and negative electrode of the battery against the corresponding connection electrodes.

[0007] FIG. 1 is an exploded perspective view of a battery package according to embodiment 1 of the present disclosure. FIG. 2 is a cross-sectional view of a battery module according to embodiment 1 of the present disclosure. FIG. 3 is a cross-sectional view taken along the arrow III-III in FIG. 1. FIG. 4 is a plan view of a wiring board of the battery package. FIG. 5 is an enlarged view of region R in FIG. 2, which is a bottom view of the wiring board. FIG. 6 is a cross-sectional view of a battery module according to embodiment 2 of the present disclosure. FIG. 7 is a cross-sectional view of a battery module according to embodiment 3 of the present disclosure. FIG. 8 is a cross-sectional view of a battery module according to embodiment 4 of the present disclosure. FIG. 9 is a cross-sectional view of a battery module according to embodiment 5 of the present disclosure. FIG. 10 is a cross-sectional view of a battery module according to embodiment 6 of the present disclosure.

[0008] In battery modules, improvements in energy density are desired.

[0009] According to one aspect of the present disclosure, the energy density of a battery module can be improved.

[0010] [Embodiment 1] A battery package and a battery module according to an embodiment of the present disclosure will be described in detail below with reference to the drawings. However, for the sake of convenience, the drawings referred to below may show only the components necessary for explaining the embodiment in a simplified form. Therefore, the battery package and the battery module according to the embodiment may include optional components not shown in the drawings. It should also be noted that the dimensions of the components in the drawings do not faithfully represent the actual dimensions of the components and the dimensional ratios of each member.

[0011] The distinction between top and bottom in the following description is for convenience and does not limit the top and bottom when the battery package and battery module are actually used. In this specification, the surface of the wiring board on which the battery is mounted is defined as the top surface. In addition, in the drawings, the Z-axis direction is the thickness direction of the battery package and battery module, and the positive direction of the Z-axis is the upward direction.

[0012] A battery package 100 and a battery module 200 according to Embodiment 1 will be described with reference to Figures 1 to 5. Figure 1 is an exploded perspective view of the battery package 100. Figure 2 is a cross-sectional view of the battery module 200 according to Embodiment 1. Figure 3 is a cross-sectional view taken along line III-III in Figure 1. Figure 4 is a plan view of the wiring board 2 of the battery package 100. Figure 5 is a bottom view of the wiring board 2.

[0013] The battery package 100 is a package for accommodating a battery. In this embodiment, the battery package 100 is a battery 7 having a positive electrode 701 and a negative electrode 702 on the same surface. In the following description, the positive electrode 701 and the negative electrode 702 may be collectively referred to as electrodes.

[0014] The battery 7 may be a chip-type all-solid-state battery or a capacitor that is an electricity storage device. The capacitor may be a chip-type capacitor, such as a multi-layer ceramic capacitor (MLCC), a tantalum capacitor, or a film capacitor.

[0015] As shown in FIG. 2 , the battery module 200 includes a battery package 100 and a battery 7 housed in the battery package 100. The battery package 100 includes a wiring board 2, a lid 3, and a sealing material 4 that bonds the wiring board 2 and the lid 3. The shape of the battery package 100 in a plan view may be, for example, rectangular. The battery 7 may be connected to the wiring board 2 via a bonding material 5. In the present disclosure, the rectangular shape is not limited to a strict rectangular shape, and may be, for example, a shape with notches at the corners and / or sides, or a shape with curved corners, as long as the shape is visually recognizable as a rectangle overall.

[0016] (Wiring Board) The wiring board 2 has a first recess 21 that forms part of the storage space S that stores the battery 7. The wiring board 2 may be a board that has connection electrodes 24 for connecting to the electrodes of the battery 7, external electrodes 25 for connecting to the electrodes of the mounting board, and internal wiring that connects the connection electrodes 24 and the external electrodes 25.

[0017] The wiring substrate 2 has an insulating base 20 including a first base 22 and a first frame 23. The first base 22 may be, for example, a flat insulator having a rectangular shape in a plan view. The first base 22 has a first surface 22A, which is the bottom surface of the first recess 21, and a second surface 22B located opposite the first surface 22A. The first frame 23 is located on the outer edge of the first surface 22A of the first base 22 and defines the inner wall (inner surface) of the first recess 21. The outer edge of the first frame 23 may overlap the outer edge of the first base 22 in a plan view. The insulating base 20 may be made of ceramics such as aluminum oxide sintered body (alumina ceramics), aluminum nitride sintered body, mullite sintered body, or glass ceramic sintered body. The insulating base 20 may include multiple laminated insulating layers. Alternatively, the first base portion 22 and the first frame portion 23 of the insulating base 20 may be integrally formed.

[0018] The first surface 22A of the wiring board 2 may include a mounting area for mounting the battery 7. The mounting area on the first surface 22A may be an area that overlaps with the battery 7 when the wiring board 2 with the battery 7 mounted thereon is viewed in plan.

[0019] The connection electrodes 24 are electrically connected to the electrodes of the battery 7. The connection electrodes 24 include a first connection electrode 241 and a second connection electrode 242, which respectively correspond to the positive electrode 701 and the negative electrode 702 of the battery 7. The connection electrodes 24 are located on the inner surface of the first recess 21. For example, the connection electrodes 24 may be located on the first surface 22A as shown in FIGS. 1 to 4 . Alternatively, the connection electrodes 24 may be located on the inner surface of the first recess 21, or may be located from the first surface 22A to the inner surface.

[0020] 2, the connection electrode 24 may extend from the mounting region of the wiring substrate 2 to the boundary between the first base portion 22 and the first frame portion 23. In other words, a portion of the connection electrode 24 may be located between the first base portion 22 and the first frame portion 23. This can improve the bonding strength between the connection electrode 24 and the insulating base 20.

[0021] The external electrode 25 is located on the second surface 22B. The external electrode 25 includes a first external electrode 251 and a second external electrode 252 connected to the first connection electrode 241 and the second connection electrode 242, respectively. As shown in FIG. 1 , the external electrode 25 may extend from the second surface 22B of the wiring board 2 to a corner between side surfaces of the wiring board 2. Alternatively, a groove may be provided in the corner of the wiring board 2, and the external electrode 25 may extend into the groove.

[0022] The internal wiring connects the connection electrode 24 and the external electrode 25. The internal wiring may include a via conductor 26 extending in the thickness direction of the first base portion 22, as shown in FIG. 2 . Alternatively, the internal wiring may include a plurality of such via conductors 26, and the connection electrode 24 and the external electrode 25 may be connected by the plurality of via conductors 26. This reduces the resistance of the internal wiring and improves the efficiency of extracting power from the battery. The internal wiring may further include a wiring conductor located inside the first base portion 22 and extending in a direction parallel to the first surface 22A.

[0023] (Lid) The lid 3 has a second recess 31 that forms part of the storage space S that houses the battery 7. The lid 3 has a second base 32 that has a third surface 32A that is the bottom surface of the second recess 31, and a second frame 33 that is located on the outer edge of the third surface 32A and defines the inner wall of the second recess.

[0024] The planar shape of the lid 3 may be, for example, rectangular. The lid 3 may contain a ceramic material, more specifically, a ceramic such as an aluminum oxide sintered body (alumina ceramics), an aluminum nitride sintered body, a mullite sintered body, or a glass ceramic sintered body. By using a ceramic material, the lid 3 can be made of the same material as the insulating base 20 of the wiring board 2. Furthermore, thermal stress due to the difference in thermal expansion between the lid 3 and the wiring board 2 is reduced, thereby improving the bonding strength and airtight sealing performance of the sealing material 4 and increasing reliability. Furthermore, because the thermal stress is reduced, the thickness of the first frame portion 23 of the wiring board 2 can be reduced, thereby increasing the storage space S.

[0025] Furthermore, even if the battery is misaligned within the storage space and comes into contact with the lid 3, the battery is an insulator and therefore no short circuit occurs between the positive and negative electrodes.

[0026] The cover 3 is not limited to a ceramic material, and may be made of a metal. An example of the cover 3 made of a metal will be described later.

[0027] (Sealant) The sealant 4 joins the wiring board 2 and the lid 3 and hermetically seals the battery 7. The sealant 4 may be a sealant containing mainly a non-conductive material, or may be a sealant containing mainly a conductive material.

[0028] More specifically, the non-conductive material used for the sealing material 4 may be a frit (glass) material. By using a non-conductive material as the sealing material 4, the possibility of a short circuit with the battery 7 can be reduced even if the sealing material 4 protrudes into the storage space S. Furthermore, even if the sealing material 4 protrudes from the upper surface of the first frame portion 23 and comes into contact with an electrode of the battery 7, a short circuit will not occur between the electrodes.

[0029] The conductive material used for the sealing material may be AuSn or solder. When AuSn or solder is used as the sealing material, the accommodation space S can be sealed by providing a metallized layer on each sealing surface of the first frame portion 23 and the second frame portion 33.

[0030] (Bonding Material) As shown in FIG. 2 , the battery module 200 may include a bonding material 5 that bonds the positive electrode 701 and negative electrode 702 of the battery 7 to the corresponding first connection electrode 241 and second connection electrode 242. The bonding material 5 is not particularly limited as long as it is a conductive bonding material, and may be, for example, a metal sinter material. The metal sinter material is a sintered bonding material that contains metal nanoparticles and functions as a bonding material with conductivity when fired. The metal nanoparticles contained in the metal sinter material may be, for example, gold, silver, copper, or silver-palladium. A silver sinter material containing silver nanoparticles is advantageous in terms of cost. When migration in the wiring board is taken into consideration, a copper sinter material or a silver-palladium sinter material may be selected.

[0031] Another example of a conductive resin that can be used as the bonding material 5 generally contains about 10% resin. In contrast, the resin content of a metal sintered material is generally less than 1%, so the amount of gas generated by the resin when exposed to high temperatures is small. When sealing the wiring board 2 and the lid 3 with the sealing material 4, the wiring board 2 and the lid 3 may be exposed to high temperatures. For example, when sealing the wiring board 2 and the lid 3 using a frit material as the sealing material 4, the sealing is performed at a high temperature of about 300 to 350°C with a lead-containing frit, and about 380 to 500°C with a lead-free frit. By using a metal sintered material with a low resin content as the bonding material 5, the possibility of poor airtight sealing due to gas generated from the resin can be reduced, even when sealing the wiring board 2 and the lid 3 at high temperatures.

[0032] 3 will be used to explain the characteristics of the battery package 100 in which the above-mentioned wiring board 2 and lid body 3 are joined by the sealing material 4. In the battery package 100, the surface surrounding the opening of the first recess 21 of the wiring board 2 and the surface surrounding the opening of the second recess 31 of the lid body 3 are joined by the sealing material 4, and the storage space S is hermetically sealed.

[0033] In FIG. 3 , H1 is the height of the first frame portion 23, and T1 is the maximum thickness of the first frame portion 23. The height H1 of the first frame portion 23 is, in other words, the depth of the first recess 21. The maximum thickness T1 of the first frame portion 23 is the length from the inner end to the outer end of the first frame portion 23 in the X direction in a vertical cross-sectional view. Furthermore, H2 is the height of the second frame portion 33, and T2 is the maximum thickness of the second frame portion 33. The height H2 of the second frame portion 33 is, in other words, the depth of the second recess 31. More specifically, the maximum thickness T2 of the second frame portion 33 is the length from the inner end to the outer end of the second frame portion 33 in the X direction in a vertical cross-sectional view. Furthermore, HT is the height of the storage space S defined by the first recess 21 and the second recess 31. In other words, the height HT of the storage space S is the sum of the height H1 of the first frame portion 23, the height H2 of the second frame portion 33, and the thickness of the sealing material 4. TP is the wall thickness of the battery package 100, and is the length from the inner end to the outer end of the first frame portion 23 and the second frame portion 33 in the X direction.

[0034] In the battery package 100, in a vertical cross section as shown in FIG. 3, the value obtained by dividing the height (HT) of the storage space S by the wall thickness (TP) of the battery package 100 is 3 or more.

[0035] If only one of the wiring board and the lid has a recess, and the other has a flat plate-like structure, a deep recess is required, resulting in a wall height greater than the wall thickness and reduced strength. Furthermore, if the recess wall is constructed using a laminate, it is difficult to form a thin and tall wall. The battery package 100 defines the storage space S with the first recess 21 in the wiring board 2 and the second recess 31 in the lid 3. Furthermore, by reducing the thickness of the frame of the wiring board 2 or the lid 3 while maintaining the storage space volume, the volume of the storage space S can be increased relative to the external volume of the package, based on the requirement of HT / TP≧3. This allows for a battery module with a high energy density to be realized without reducing the strength of the package.

[0036] In the battery package 100, the height (H1) of the first frame portion 23 relative to the height (HT) of the storage space S may be 30% or more and 70% or less. For example, the ratio of H1 to HT may be 40% or more and 60% or less, or even approximately 50%. If the difference in the depth of the recesses between the wiring board 2 and the lid body 3 is extreme, the strength of the one with the deeper recess may be reduced. With the above configuration, the height (HT) of the storage space S can be increased without excessively reducing the strength of either the wiring board 2 or the lid body 3, thereby achieving a battery module with high energy density.

[0037] In the battery package 100, the aspect ratio (H1 / T1) of the first frame portion 23, which is determined by dividing the height (H1) of the first frame portion 23 by the maximum thickness (T1) of the first frame portion 23, may be 1.5 or more in a vertical cross-sectional view as shown in Fig. 3. By configuring the first frame portion 23 so that the aspect ratio (H1 / T1) is 1.5 or more, the volume of the accommodation space (the volume of the first recess 21) relative to the external volume of the wiring substrate 2 can be increased.

[0038] 3, the battery package 100 may have an aspect ratio (H2 / T2) of the second frame 33, which is determined by dividing the height (H2) of the second frame 33 by the maximum thickness (T2) of the second frame 33, of 1.5 or more. By configuring the second frame 33 so that the aspect ratio (H2 / T2) is 1.5 or more, the volume of the storage space (volume of the second recess 31) relative to the external volume of the lid 3 can be increased.

[0039] Because the wiring board 2 and the lid 3 have the first frame portion 23 and the second frame portion 33, respectively, the rigidity of the wiring board and the lid can be obtained mainly from the frame portions. This allows the thickness of the first base portion 22 and the second base portion 32, respectively, to be thin, thereby increasing the storage space volume. Furthermore, because the base portion of the first base portion 22 of the wiring board 2 is thin, the internal wiring connecting the connection electrodes 24 and the external electrodes 25 can be short, thereby improving power extraction efficiency.

[0040] FIG. 6 is an enlarged view of region R in FIG. 2 . As shown in FIG. 6 , the outer surface of the second frame portion 33 may have an inwardly sloping surface 331 on the opening side of the second recess 31. In other words, the outer edge of the second frame portion 33 at the opening side of the second recess 31 may be located inside the outer edge of the second frame portion 33 in a plan view. By having the inclined surface 331, even if the first frame portion 23 and the second frame portion 33 have the same thickness, a pool of sealing material 4 is formed between the inclined surface 331 and the upper surface of the first frame portion 23, increasing the bonding area and improving bonding strength. Furthermore, by having the inclined surface 331 on the outer surface, a pool of sealing material 4 can be formed on the outside where stress is greater, thereby improving strength compared to when it is on the inside side. The inclined surfaces may be located on both the inside and outside of the second frame portion 33.

[0041] In the battery package 100, the outer surface of the first frame portion 23 of the wiring board 2 may have an inclined surface that slopes inward toward the opening surface of the first recess 21. The outer surfaces of both the first frame portion 23 and the second frame portion 33 may have an inclined surface. Since only the second frame portion 33 of the upper lid body 3 has an inclined surface, the sealing material 4 is more likely to remain between the lid body 3 and the wiring board 2.

[0042] [Embodiment 2] Another embodiment of the present disclosure will be described below. For convenience of explanation, the same reference numerals will be used to designate components having the same functions as those described in the above embodiment, and the description thereof will not be repeated.

[0043] Fig. 7 is a cross-sectional view of a battery module 200B according to embodiment 2. The battery module 200B includes a battery package 100B and a battery 7. As in the battery package 100B shown in Fig. 7, the wiring substrate 2 and the lid body 3 may each include a plurality of laminated ceramic insulating layers IL.

[0044] The wiring board 2 and the lid 3, which include multiple laminated ceramic insulating layers IL, can be manufactured, for example, as follows. When the ceramic insulating layers of the wiring board 2 and the lid 3 are made of an aluminum oxide sintered body, a slurry is produced by adding an appropriate organic binder, solvent, and the like to raw material powders such as aluminum oxide and silicon oxide and mixing them. This slurry is then formed into sheets using a doctor blade method, a calendar roll method, or the like to produce ceramic green sheets for the insulating layers. A rectangular ceramic green sheet that will become the first base 22 and the second base 32 and multiple rectangular frame-shaped ceramic green sheets that will become the first frame 23 and the second frame 33 are laminated to produce a laminate. The laminate is then fired at a high temperature (approximately 1300 to 1600°C) to produce the wiring board 2 or the lid 3.

[0045] In fabricating the wiring board 2, a metal paste made by mixing tungsten powder with an organic solvent and an organic binder is placed on the green sheet that will become the first base portion 22 at positions that will become the connection electrodes 24, external electrodes 25, and internal wiring, and then the green sheet is fired. This produces the wiring board 2 with wiring.

[0046] When the wiring substrate 2 or the lid 3 includes multiple insulating layers, if the height of the frame is increased to ensure the storage volume, the thickness of the frame must be increased to ensure manufacturing precision during manufacturing and strength after sintering. By making the battery package 100B satisfy HT / TP≧3, a battery module with high energy density can be realized without reducing the strength of the package.

[0047] The outer and inner surfaces of the second frame 33 may be approximately perpendicular to the third surface 32A. The perpendicular inner surfaces allow the volume of the storage space S to be increased relative to the external volume of the lid 3. The outer and inner surfaces of the first frame 23 may be approximately perpendicular to the first surface 22A. The perpendicular inner surfaces allow the volume of the storage space S to be increased relative to the external volume of the wiring board 2.

[0048] Furthermore, because the outer and inner surfaces of the second frame 33 are perpendicular, the wall thickness of the second frame 33 is uniform in the height direction, allowing the entire second frame 33 to have the maximum thickness, resulting in excellent lid strength. Similarly, because the outer and inner surfaces of the first frame 23 are perpendicular, the wall thickness of the first frame 23 is uniform in the height direction, allowing the entire first frame 23 to have the maximum thickness, resulting in excellent board strength. This allows the frame height to be increased, maximizing the volume of the storage space S relative to the external volume of the package.

[0049] Furthermore, in the X direction in the vertical cross section, the position of the inner surface of the second frame portion 33 may be the same as the position of the inner surface of the first frame portion 23. This allows the accommodation space to be further increased.

[0050] By configuring the lid 3 with multiple laminated ceramic insulating layers IL, it is possible to realize a lid in which the inner and outer walls of the second frame portion 33 have a shape that is approximately perpendicular to the third surface 32A, thereby increasing the internal volume of the second recess 31. Furthermore, the depth of the second recess 31 can be easily set by changing the number of ceramic insulating layers IL and the thickness of each layer. To change the depth or manufacture a product with a different depth, a different mold is required when forming by pressing, but with lamination, it is possible to simply change the number of layers or layer thickness, making manufacturing easier.

[0051] In the first frame portion 23 of the wiring substrate 2, the thickness of the first frame portion 23 on the opening side of the first recess 21 may be greater than the thickness of the bottom surface (first surface 22A) side. For example, the thickness of the ceramic insulating layer IL located at the top of the first frame portion 23 of the wiring substrate 2 in the direction perpendicular to the inner wall of the first frame portion 23 may be greater than the thickness of the ceramic insulating layer IL located at the bottom.

[0052] The greater thickness on the opening side of the first recess 21 increases the bonding area with the sealing material 4, thereby improving the bonding strength between the lid 3 and the wiring board 2. Furthermore, the thickness of the bottom side of the first recess 21 is smaller than that on the opening side, so when the battery 7 and the wiring board 2 are bonded using bonding material 5, the bonding material 5 can spread outward, improving the bonding strength between the battery 7 and the wiring board 2. In this case, in the second frame portion 33 of the lid 3, the thickness of the second frame portion 33 on the opening side of the second recess 31 may be greater than the thickness on the bottom (third surface 32A) side.

[0053] 7 , when the connection electrode 24 extends to the boundary between the first frame portion 23 and the first base portion 22, the via conductor 26 connecting the connection electrode 24 and the external electrode 25 may be positioned so as to overlap the first frame portion 23 in a plan view. With this configuration, even if the first base portion 22 is thin, the possibility of cracks originating from the via conductor 26 can be reduced, and the strength of the battery package 100B can be improved.

[0054] 8 is a cross-sectional view of a battery module 200C according to embodiment 3. The battery module 200C includes a battery package 100C and a battery 7. The battery package 100C includes a wiring substrate 2, a lid 3C, and a sealing material 4.

[0055] The lid 3C may be formed by pressing a metal plate into a cup shape. In the case of a metal lid having a second frame portion 33 with a thickness equal to or substantially equal to that of the first frame portion 23, as in the lid 3 of the first embodiment, thermal stress due to the difference in thermal expansion is greater than in the case of a ceramic lid. By forming a cup-shaped lid from a metal plate thinner than the first frame portion 23, thermal stress can be reduced, allowing the thickness of the first frame portion 23 of the wiring board 2 to be reduced and the storage space to be increased. The metal material used for the lid 3C may be one with a small thermal expansion difference from ceramics, such as an iron-nickel (Fe—Ni) alloy or an iron-nickel-cobalt (Fe—Ni—Co) alloy.

[0056] When joining the metal lid 3C and the wiring board 2, a joining metal layer such as a metallized layer or a seal ring may be provided in advance on the upper surface of the wiring board 2, and the lid 3C may be joined to the joining metal layer by welding such as seam welding or laser welding. Joining by seam welding or laser welding results in localized heating, which reduces the thermal effects on the battery 7.

[0057] The lid body 3C includes a second base 32 having a third surface 32A, which is the bottom surface of the second recess 31, and a second frame portion 33 located on the outer edge of the third surface 32A and defining the inner wall of the second recess. In the lid body 3C, H2 is the height of the second frame portion 33. Specifically, H2 may be the distance between the third surface 32A and the joint surface where the lid body 3C contacts the sealing material 4 in the battery package 100C. T2 is the length from the inner end to the outer end in the X direction. TP is the wall thickness of the battery package 100 and is defined as the length from the outer end of the first frame portion 23 to the inner end of the second frame portion 33. In the vertical cross-sectional view shown in FIG. 8 , the battery package 100C has a ratio HT / TP≧3. This configuration allows the volume of the storage space S to be increased relative to the external volume of the package without reducing the strength of the package, resulting in a battery module with high energy density.

[0058] 9 is a cross-sectional view of a battery module 200D according to embodiment 4. The battery module 200D includes a battery package 100D and a battery 7. The battery package 100D includes a wiring substrate 2, a lid 3D, and a sealing material 4.

[0059] As shown in FIG. 9 , the inner surface of the lid 3D (the inner surface of the second frame 33) may be an inclined surface at an angle relative to the third surface 32A. The angle between the third surface 32A and the inclined surface is an obtuse angle. This shape reduces stress concentration at the corner between the third surface 32A and the inner surface of the second frame 33, thereby reducing the likelihood of cracks originating from the corner. Furthermore, the thickness of the bonding surface of the second frame 33 is smaller than the thickness of the bonding surface of the first frame 23. This allows the sealing material 4 to remain between the inclined surface and the upper surface of the wiring substrate 2, thereby improving the bonding strength between the wiring substrate 2 and the lid 3C. By reducing the thickness of the bonding surface of the second frame 33 and inclining the inner surface as shown in FIG. 9 , the likelihood of cracks occurring at the corner can be reduced without reducing the size of the housing space S, and the retention of the sealing material improves the bonding strength.

[0060] The lid 3D can be obtained by, for example, pressing ceramic powder into a cup shape and then firing the pressed cup. Alternatively, the lid 3D may be formed by stacking frame-shaped ceramic insulating layers whose inner surfaces are inclined.

[0061] Alternatively, the inner surface of the lid 3D (the inner surface of the second frame 33) may be perpendicular to the third surface 32A, and the corner where the inner surface and the third surface 32A join may be an inclined surface or a curved surface. Even with this configuration, stress concentration at the corner between the third surface 32A and the inner surface of the second frame 33 can be reduced, and the possibility of cracks originating from the corner can be reduced.

[0062] 10 is a cross-sectional view of a battery module 200E according to embodiment 5. The battery module 200E includes a battery package 100E and a battery 7. The battery package 100E includes a wiring substrate 2, a lid 3D, a sealing material 4, and a leaf spring 6E. The leaf spring 6E is an example of an elastic member according to the present disclosure.

[0063] The leaf spring 6E presses the battery 7 toward the first surface 22A of the wiring board 2. More specifically, the leaf spring 6E presses the positive electrode 701 and negative electrode 702 of the battery 7 against the corresponding first connection electrode 241 and second connection electrode 242. The leaf spring 6E is a metal leaf spring.

[0064] The cover 3E may be made of ceramics containing a ceramic material, and may have a recess 32C on the third surface 32A for accommodating the leaf spring 6E. The recess 32C in the cover 3E allows the leaf spring 6E to be positioned appropriately and reduces lateral displacement of the leaf spring 6E. This reduces the possibility of the leaf spring 6E pressing against the battery 7 being displaced, resulting in a force that tilts the battery, and improves the reliability of the connection between the battery 7 and the first connection electrode 241 and second connection electrode 242.

[0065] Because the battery module 200E includes the leaf springs 6E, the bonding material 5 that bonds the batteries 7 and the wiring board 2 is not necessary. Metal leaf springs are components that are less susceptible to deterioration over the long term, allowing the battery module 200E to have excellent long-term reliability. Furthermore, the leaf springs 6E do not require processes such as sintering or hardening. This reduces temperature-related deterioration of the batteries 7. Alternatively, the battery module 200E may include both the bonding material 5 that bonds the batteries 7 and the wiring board 2 and the leaf springs 6E. By including both, connection reliability is further improved.

[0066] 10 , in a plan view, the outer shape of the lid body 3E may be smaller than the outer shape of the wiring board 2. In other words, the length of one side of the lid body 3E may be shorter than the length of one side of the corresponding wiring board 2. This configuration reduces the possibility that the outer dimensions of the battery package 100E will change due to misalignment of the lid body 3E.

[0067] Furthermore, in a planar perspective view, the opening diameter of the first recess 21 (the inner diameter of the first frame 23) may be smaller than the opening diameter of the second recess 31 (the inner diameter of the second frame 33). In other words, the thickness of the first frame 23 may be larger than the thickness of the second frame 33. This allows a fillet of the sealing material 4 to be formed from the upper surface of the wiring board 2 to the inner and outer surfaces of the second frame 33, thereby improving the bonding strength between the wiring board 2 and the lid 3E. This also reduces the possibility that the storage space S of the battery package 100E will become smaller due to misalignment of the lid 3E.

[0068] 10 shows an example in which the thickness of the first frame portion 23 is greater than the thickness of the second frame portion 33, but the thickness of the first frame portion 23 may be less than the thickness of the second frame portion 33. Also, while Fig. 10 shows an example in which the outer shape of the wiring board 2 is greater than the outer shape of the lid body 3E, the outer shape of the wiring board 2 may be smaller than the outer shape of the lid body 3E. Even in such a case, the same effect as the example shown in Fig. 10 can be obtained.

[0069] 11 is a cross-sectional view of a battery module 200F according to embodiment 6. The battery module 200F differs from the battery module 200E of embodiment 5 in that it includes a coil spring 6F instead of the leaf spring 6E. The coil spring 6F is an example of an elastic member according to the present disclosure.

[0070] The cover 3F may be made of ceramics including a ceramic material, and may have a recess 32C in the third surface 32A for accommodating the coil spring 6F.

[0071] The coil spring 6F may be made of metal or ceramic. The elastic member according to the present disclosure is not limited to the leaf spring 6E of the fifth embodiment or the coil spring 6F of the sixth embodiment, but may be any elastic member that can press the battery 7 toward the first surface 22A of the wiring board 2 when pressed by the lids 3E and 3F.

[0072] [Other Aspects] In the above-described embodiment, an example is shown in which each battery package houses one battery 7, but the battery package may house multiple batteries 7. In this case, the number and arrangement of the first connection electrodes 241 and second connection electrodes 242 in the battery package may be changed as appropriate depending on the number and arrangement of the housed batteries 7. Furthermore, the battery package may house electronic components such as a semiconductor element for battery control or a capacitor.

[0073] [Summary] (1) A battery package according to aspect 1 of the present disclosure is a battery package for accommodating a battery, comprising: a wiring board having a first recess that forms a part of an accommodating space for accommodating the battery; a lid body having a second recess that forms another part of the accommodating space; and a sealing material that joins the wiring board and the lid body; the wiring board has an insulating base including a first base having a first surface that is the bottom surface of the first recess, and a first frame portion located on the outer edge of the first surface and defining an inner wall of the first recess; the lid body includes a second base having a third surface that is the bottom surface of the second recess, and a second frame portion located on the outer edge of the third surface and defining the inner wall of the second recess; and in a vertical cross-sectional view, a value obtained by dividing the height of the accommodating space by the wall thickness of the battery package is 3 or more.

[0074] (2) A battery package according to Aspect 2 of the present disclosure is the battery package according to Aspect 1, wherein the insulating substrate includes a plurality of laminated ceramic insulating layers.

[0075] (3) A battery package according to aspect 3 of the present disclosure is the battery package of aspect 1 or 2, wherein the height of the first frame portion relative to the height of the storage space is 30% or more and 70% or less.

[0076] (4) In a battery package according to aspect 4 of the present disclosure, in any one of aspects 1 to 3 above, the aspect ratio of the first frame portion, as determined by dividing the height of the first frame portion by the maximum thickness of the first frame portion, is 1.5 or greater in a vertical cross-sectional view.

[0077] (5) A battery package according to aspect 5 of the present disclosure is the battery package of any one of aspects 1 to 4, wherein the lid includes a ceramic material.

[0078] (6) A battery package according to a sixth aspect of the present disclosure is the battery package of any one of the first to fifth aspects, wherein the lid body includes a plurality of laminated ceramic insulating layers.

[0079] (7) In a battery package according to aspect 7 of the present disclosure, in any of aspects 1 to 6 above, the aspect ratio of the second frame portion, as determined by dividing the height of the second frame portion by the maximum thickness of the second frame portion, is 1.5 or greater in a vertical cross-sectional view.

[0080] (8) A battery package according to aspect 8 of the present disclosure is any one of aspects 1 to 7 above, wherein the outer surface of the second frame portion has an inwardly sloping surface on the side of the opening surface of the second recess.

[0081] (9) A battery package according to Aspect 9 of the present disclosure is the battery package according to any one of Aspects 1 to 8, wherein the sealing material includes a non-conductive material.

[0082] (10) A battery package according to aspect 10 of the present disclosure is any one of aspects 1 to 9 above, wherein the thickness of the first frame portion on the opening side of the first recess is greater than the thickness of the first frame portion on the bottom side of the first recess.

[0083] (11) A battery module according to aspect 11 of the present disclosure is a battery package according to any one of aspects 1 to 10 above, comprising: a battery package having a plurality of connection electrodes on the inner surface of the first recess; a battery having a positive electrode and a negative electrode; and a metal sinter material that joins the positive electrode and negative electrode of the battery to the corresponding connection electrodes.

[0084] (12) A battery module according to aspect 12 of the present disclosure is a battery package according to any one of aspects 1 to 10 above, comprising a battery package having a plurality of connection electrodes on the inner surface of the first recess, a battery having a positive electrode and a negative electrode, and an elastic member that presses the positive electrode and negative electrode of the battery against the corresponding connection electrodes.

[0085] [Additional Notes] The invention according to the present disclosure has been described above based on the drawings and examples. However, the invention according to the present disclosure is not limited to the above-described embodiments. In other words, the invention according to the present disclosure can be modified in various ways within the scope of the present disclosure, and embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the invention according to the present disclosure. In other words, it should be noted that a person skilled in the art could easily make various modifications or corrections based on the present disclosure. It should also be noted that these modifications or corrections are included in the scope of the present disclosure.

[0086] DESCRIPTION OF SYMBOLS 100, 100B, 100C, 100D, 100E... Battery package 2... Wiring substrate 20... Insulating base 21... First recess 22... First base 23... First frame 24... Connection electrode 25... External electrode 26... Via conductor 3, 3C, 3D, 3E, 3F... Lid 31... Second recess 32... Second base 33... Second frame 4... Sealing material 5... Bonding material 6E... Leaf spring (elastic member) 6F... Coil spring (elastic member) 7... Battery 701... Positive electrode 702... Negative electrode 200, 200B, 200C, 200D, 200E, 200F... Battery module

Claims

1. A battery package for accommodating a battery, comprising: a wiring board having a first recess that forms part of the storage space for accommodating the battery; a lid having a second recess that forms another part of the storage space; and a sealing material that joins the wiring board and the lid, wherein the wiring board includes a first base having a first surface that is the bottom of the first recess, and a first frame that is located on the outer edge of the first surface and defines the inner wall of the first recess, and the lid includes a second base having a third surface that is the bottom of the second recess, and a second frame that is located on the outer edge of the third surface and defines the inner wall of the second recess, and wherein, in a vertical cross-sectional view, the value obtained by dividing the height of the storage space by the wall thickness of the battery package is 3 or more.

2. The battery package according to claim 1, wherein the wiring substrate comprises a plurality of laminated ceramic insulating layers.

3. The battery package according to claim 1 or 2, wherein the height of the first frame portion is 30% to 70% of the height of the storage space.

4. A battery package according to any one of claims 1 to 3, wherein the aspect ratio of the first frame portion, determined by dividing the height of the first frame portion by the maximum thickness of the first frame portion, is 1.5 or greater in a vertical cross-sectional view.

5. The battery package according to any one of claims 1 to 4, wherein the lid comprises a ceramic material.

6. The battery package according to any one of claims 1 to 5, wherein the lid includes a plurality of laminated ceramic insulating layers.

7. A battery package according to any one of claims 1 to 6, wherein the aspect ratio of the second frame portion, defined by dividing the height of the second frame portion by the maximum thickness of the second frame portion in a vertical cross-sectional view, is 1.5 or greater.

8. A battery package according to any one of claims 1 to 7, wherein the outer surface of the second frame has an inwardly sloping surface on the side of the opening of the second recess.

9. The battery package according to any one of claims 1 to 8, wherein the sealing material comprises a non-conductive material.

10. A battery package as described in any one of claims 1 to 9, wherein the thickness of the first frame portion on the opening side of the first recess is greater than the thickness of the first frame portion on the bottom side of the first recess.

11. A battery module comprising: a battery package according to any one of claims 1 to 10, the battery package having a plurality of connection electrodes on the inner surface of the first recess; a battery having a positive electrode and a negative electrode; and a metal sinter material that joins the positive electrode and negative electrode of the battery to the corresponding connection electrodes.

12. A battery module comprising: a battery package according to any one of claims 1 to 10, the battery package having a plurality of connection electrodes on the inner surface of the first recess; a battery having a positive electrode and a negative electrode; and an elastic member that presses the positive electrode and negative electrode of the battery against the corresponding connection electrodes.

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