Mold and injection molding method

Abstract

To provide injection mold that can improve the productivity of the process of covering the battery sides with resin.SOLUTION: The mold 100 includes a space 140 in which a first end 211 of a battery 200 can be placed, and a fixing member 150 capable of fixing the battery with the first end of the battery placed in the space, the space being formed such that a second end of the battery protrudes from the space when the first end of the battery is placed in the space, the fixing member having a fixed 151 and a movable portion 152, the fixed portion is configured to support the first end face of the battery, the movable portion is movable in a thickness direction and is capable of pressing the second end face of the battery, and the fixing member is capable of fixing the battery by sandwiching the first and second end faces of the battery between the fixed and movable portions and the pressure applied to the battery from the movable portion is set to be below a predetermined threshold value.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] This application relates to a mold and an injection molding method.

Background Art

[0002] Lithium-ion batteries are widely used as portable power sources for personal computers, mobile terminals, etc., and vehicle power sources for electric vehicles, hybrid vehicles, etc. A lithium-ion battery is composed of a positive electrode, a negative electrode, and an electrolyte layer, and among the materials constituting these members, there are members that deteriorate due to the intrusion of air, water, etc. from the outside. Therefore, in order to ensure the waterproofness and airtightness inside the battery, a technique of covering the battery side surface with resin is known. As a method of covering the battery side surface with resin, for example, a method using injection molding can be mentioned. For example, a typical injection molding mold is disclosed in Patent Document 1.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, when covering the battery side surface with resin by injection molding, the battery end is inserted into the cavity of the injection molding mold to fix the position of the battery. Then, by injecting resin into the cavity, the battery side surface can be covered with resin. However, there may be variations in the thickness of the battery due to manufacturing tolerances, and there is a problem that the battery cannot be properly fixed in the cavity. In addition, in the configuration of a conventional mold, there is a problem that a dedicated mold must be prepared according to the battery size. It is desired to solve these problems and improve the productivity of the process of covering the battery side surface with resin by injection molding.

[0005] Therefore, in view of the above circumstances, a main object of the present disclosure is to provide a mold and an injection molding method capable of improving the productivity of the process of covering the side surface of a battery with resin.

Means for Solving the Problems

[0006] The present disclosure provides at least the following aspects.

[0007] A first aspect is an injection mold used for covering the side surface of a battery with resin, including a space capable of arranging a first end portion including a first side surface of the battery, and a fixing member capable of fixing the battery in a state where the first end portion of the battery is arranged in the space. The space is formed such that a second end portion, which is located on the side opposite to the first end portion of the battery when the first end portion of the battery is arranged in the space, protrudes from the space. The fixing member has a fixed portion and a movable portion. The fixed portion is configured to support a first end surface arranged on one side in the thickness direction of the battery. The movable portion is movable in the thickness direction and can press a second end surface arranged on the side opposite to the first end surface of the battery. The fixing member can fix the battery by sandwiching the first end surface and the second end surface of the battery with the fixed portion and the movable portion, and the pressure applied to the battery from the movable portion is set to be equal to or less than a predetermined threshold value.

[0008] A second aspect is the mold according to the first aspect, wherein the fixing member has a movable auxiliary portion for moving the movable portion in the thickness direction. The movable portion has a first inclined portion that inclines in a direction orthogonal to the thickness direction on a surface in the thickness direction and opposite to the battery side. The movable auxiliary portion has a second inclined portion that inclines along the first inclined portion. The movable portion is moved in the thickness direction by moving the movable auxiliary portion so that the second inclined portion of the movable auxiliary portion contacts along the first inclined portion of the movable portion.

[0009] The third aspect is an injection molding method for covering the side surface of a battery with resin using the mold according to the first aspect or the second aspect, including: an arranging step of arranging a first end portion of the battery in a space of the mold; a fixing step of fixing the battery with a solid member in a state where the first end portion of the battery is arranged in the space; and an injection molding step of injecting resin into the space to cover the first end portion of the battery with resin. In the fixing step, the pressure applied to the battery from the movable part is set to be equal to or less than a predetermined threshold value. In the injection molding step, the amount of resin injected into the space is adjusted according to the position of the movable part.

Effect of the Invention

[0010] According to the mold and the injection molding method of the present disclosure, the productivity of the process of covering the side surface of the battery with resin can be improved.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Mode for Carrying Out the Invention

[0012] [Injection Molding Mold] The mold of the present disclosure will be described using the mold 100 which is an embodiment.

[0013] The mold 100 is an injection mold used to cover the side surface of the battery 200 with resin. A plan view of the battery 200 installed in the mold 100 is shown in FIG. 1. A cross-sectional view taken along the line II-II of FIG. 1 is shown in FIG. 2. Hereinafter, the description will be made using the directions shown in FIGS. 1 and 2. The x direction is the longitudinal direction, the y direction is the short-side direction, and the z direction is the thickness direction.

[0014] As shown in FIG. 1, the battery 200 has a rectangular shape when viewed in the thickness direction, and has two end faces arranged in the thickness direction and four side faces around it. The mold 100 covers one of the side faces of the battery 200 with resin. Hereinafter, the side face of the battery 200 that is to be covered with resin by the mold 100 is referred to as the first side face 210.

[0015] <Mold 100> As shown in FIG. 2, the mold 100 includes an upper mold 110, a side mold 120, and a lower mold 130. A space (cavity) 140 is formed by these members, in which the first end portion 211 including the first side face 210 of the battery 200 can be arranged.

[0016] The upper mold 110 is a member arranged at the upper part of the mold 100 and forms the upper surface of the space 140. The side mold 120 is a member arranged between the upper mold 110 and the lower mold 130 and forms the side surface of the space 140. The lower mold 130 is a member arranged at the lower part of the mold 100 and forms the lower surface of the space 140. Further, the lower mold 130 has a shape extending in the longitudinal direction more than the space 140 and has a fixing portion 151 for fixing the battery 200 outside the space 140. Note that the configuration of the mold 100 forming the space 140 is not limited to the form including the above-described upper mold 110, side mold 120, and lower mold 130. For example, the side mold 120 and the lower mold 130 may be integrated to form one mold. The fixing part 151 is a convex part protruding in the thickness direction. The fixing part 151 also serves to block the resin so that the resin does not leak from the space 140 during injection molding. The space 140 has a rectangular cross-section. Further, the space 140 has an opening on one side in the longitudinal direction (the left side of the paper in FIG. 2), and the surfaces other than the opening are formed by the upper mold 110, the side mold 120, and the lower mold 130. The battery 200 is inserted into the space 140 through the opening. Although the illustrated space 140 is an example with a rectangular cross-section, the shape of the space 140 is not limited to this, and it may have various forms such as a circular cross-section or an elliptical cross-section, and can be appropriately set according to the shape of the injection-molded resin to be formed.

[0017] The space 140 is formed such that when the first end portion 211 of the battery 200 is disposed in the space 140, the second end portion 221 (the second side surface 220) (see FIG. 1) disposed on the side opposite to the first end portion 211 of the battery 200 protrudes from the space 140. In other words, this means that only the first end portion 211 of the battery 200 is disposed in the space 140. Thereby, different from a general injection molding die, injection molding can be performed on the first end portion 211 of the battery 200 with a small die.

[0018] Also, for the space 140, at least a part of the first end portion 211 may be disposed. FIG. 1 shows a form in which a part of the first end portion 211 of the battery 200 can be disposed in the space 140. However, the die 200 may be in a form in which the entire first end portion 211 of the battery 200 can be disposed in the space 140.

[0019] The size of the space 140 is set according to the range in which the first end portion 211 is covered with resin. For example, the length L1 in the longitudinal direction of the space 140 is preferably more than 0 mm and 100 mm or less, more preferably 3 mm or more and 50 mm or less, and even more preferably 5 mm or more and 30 mm or less (FIG. 2). The length in the thickness direction of the space 140 is set according to the size of the battery 200. The length in the short side direction of the space 140 may be set according to the purpose. For example, as shown in FIG. 1, when a part of the side surface 210 (first end portion 211) of the battery 200 is covered with resin, the length in the short side direction of the space 140 may be shorter than the length in the short side direction of the battery 200. When the entire side surface 210 (first end portion 211) of the battery 200 is covered with resin, the length in the short side direction of the space 140 may be longer than the length in the short side direction of the battery 200.

[0020] The mold 100 includes a fixing member 150 capable of fixing the battery 200 in a state where the first end portion 211 of the battery 200 is disposed in the space 140 in order to appropriately perform injection molding. The fixing member 150 has a fixing portion 151, a movable portion 152, a movable auxiliary portion 153, and a control portion 154.

[0021] The fixing portion 151 is a convex portion provided on the lower mold 130 described above, and is configured to support the first end surface 230 disposed on one side in the thickness direction of the battery 200. The movable portion 152 has a floating structure, is movable in the thickness direction, and can press the second end surface 240 disposed on the side opposite to the first end surface 230 of the battery 200. Further, the movable portion 152 has a first inclined portion 152a that inclines in a direction orthogonal to the thickness direction (longitudinal direction in FIG. 2) on the surface opposite to the battery 200 side in the thickness direction. The movable auxiliary portion 153 has a second inclined portion 153a that inclines along the first inclined portion 152a, and is movable in a direction orthogonal to the thickness direction (longitudinal direction in FIG. 2). The control portion 154 is a member that controls the movement of the movable auxiliary portion 153. As the control portion 154, for example, a servo cylinder may be used.

[0022] A mechanism for fixing the battery 200 using the fixing member 150 will be described. As shown in FIG. 2, first, the movable auxiliary part 153 is moved to the first end part 211 side in the longitudinal direction (the right side of the paper surface in FIG. 2) and brought into contact with the movable part 152. Specifically, the control part 154 is operated to bring the second inclined part 153a of the movable auxiliary part 153 into contact with the first inclined part 152a of the movable part 152. Next, by further moving the movable auxiliary part 153 to the first end part 211 side in the longitudinal direction, the second inclined part 153a pushes the first inclined part 152b in the thickness direction, and the movable part 152 moves toward the battery 200 side in the thickness direction. Then, the movable part 152 presses the second end face 240 of the battery 200. Since the first end face 230 of the battery 200 is supported by the fixing part 151, the battery 200 is fixed by being sandwiched between the fixing part 151 and the movable part 152.

[0023] FIG. 3 corresponds to FIG. 2 and shows a schematic cross-sectional view of the mold 100 in a state where the battery 200 is fixed by the fixing member 150. As shown in FIG. 3, when the battery 200 is fixed by the fixing member 150, a parting surface (PL in FIG. 3) is formed between the side surface of the movable part 152 and the side surface of the upper mold.

[0024] In this way, the fixing member 150 can move the movable part 152 in the thickness direction by moving the movable auxiliary part 153 in the longitudinal direction so that the second inclined part 153a of the movable auxiliary part 153 contacts along the first inclined part 152a of the movable part 152. Then, the fixing member 150 can fix the battery 200 by sandwiching the first end face 230 and the second end face 240 of the battery 200 between the fixing part 151 and the movable part 152.

[0025] Here, the fixing member 150 is set such that the pressure applied from the movable part 152 to the battery 200 becomes equal to or less than a predetermined threshold value. Thereby, the battery 200 with relatively low strength can be appropriately fixed. Further, even when there is variation in the thickness of the battery 200 due to manufacturing tolerances, the movable part 152 follows the thickness of the battery, and the battery 200 can be fixed with an appropriate pressure while suppressing damage to the battery 200. By stably fixing the battery 200, burr suppression and deviation due to injection pressure can be suppressed. The predetermined threshold value may be set to a pressure at which the battery 200 does not break, according to the strength of the battery 200 and the like.

[0026] The mold 100 injects the resin R into the space 140 with the battery 200 fixed, and covers the first end portion 211 including the first side surface 211 of the battery 200 with the resin R. Here, the amount of resin injected into the space 140 may be adjusted according to the position of the movable part 152 (that is, the thickness of the battery 200). Alternatively, the thickness of the battery 200 may be estimated from the stop position of the control part 154, and the resin amount may be set. Thereby, an appropriate amount of resin can be injected into the space 140.

[0027] In addition, in one embodiment, the mold 200 that covers the first end portion 211 including the first side surface 210 arranged in the longitudinal direction of the battery 200 with resin is shown, but the mold 200 is not limited to this form. The mold 200 can cover any end portion of the battery 200 with resin. For example, an end portion including a side surface arranged in the short side direction of the battery 200 can be covered with resin.

[0028] Further, the mold 100 may include members other than the above members. For example, it may include a member for injecting resin into the space 140 and the like.

[0029] <Battery 200> As described above, the battery 200 has a rectangular shape when viewed in the thickness direction. The type of the battery 200 is not particularly limited. The battery 200 may be a liquid-based battery or a solid battery. The battery 200 may be of a monopolar type or a bipolar type. The battery 200 may be a lithium-ion battery or a sodium-ion battery. Resin may be disposed on the side surface of the battery 200. Hereinafter, a case where the battery 200 has a configuration of a typical bipolar lithium-ion battery will be described. However, the battery 200 is not limited to this form.

[0030] Fig. 4 shows a schematic cross-sectional view focusing on the first end portion 211 of the battery 200. The battery 200 includes a plurality of bipolar electrodes 250 and a plurality of electrolyte layers 260, and the bipolar electrodes 250 and the electrolyte layers 260 are alternately stacked. The number of the bipolar electrodes 250 and the electrolyte layers 260 is not particularly limited and may be appropriately set according to the target battery performance. Further, the battery 200 further includes an end positive electrode 270 disposed at one end in the stacking direction and an end negative electrode 280 disposed at the other end in the stacking direction.

[0031] The bipolar electrode 250 includes a current collector 251, a positive electrode layer 252 disposed on one surface of the current collector 251, and a negative electrode layer 253 disposed on the other surface of the current collector 251. Thus, the bipolar electrode 250 includes electrode layers of different polarities on both surfaces of the current collector 251.

[0032] The current collector 251 is a sheet-like conductive member. Examples of the current collector 251 include metal foils such as stainless steel, iron, copper, aluminum, titanium, and nickel. The metal foil may be made of an alloy containing two or more of these metals. Further, the metal foil may be subjected to surface treatment such as predetermined plating. The current collector 251 may be composed of a plurality of metal foils. In this case, the metal foils may be joined with an adhesive or the like, or may be joined by pressing or the like. The shape of the current collector 251 may be rectangular. The thickness of the current collector 251 is not particularly limited, but is, for example, 5 μm or more and 70 μm or less.

[0033] The positive electrode layer 252 contains a positive electrode active material. The positive electrode active material is not particularly limited and may be appropriately selected from known materials according to the intended battery performance. For example, composite oxides, metal lithium, sulfur, etc. may be mentioned. The composition of the composite oxide includes, for example, at least one of iron, manganese, titanium, nickel, cobalt, and aluminum, and lithium. Examples of the composite oxide include olivine-type lithium iron phosphate (LiFePO4), etc.

[0034] The positive electrode layer 252 may optionally contain a conductive assistant. The conductive assistant is not particularly limited and may be appropriately selected from known materials according to the intended battery performance. For example, carbon materials such as acetylene black, carbon black, and graphite may be mentioned.

[0035] The positive electrode layer 252 may optionally contain a binder. The binder is not particularly limited and may be appropriately selected from known materials according to the intended battery performance. For example, fluorine-containing resins such as polyvinylidene fluoride, polytetrafluoroethylene, and fluororubber; thermoplastic resins such as polypropylene and polyethylene; imide resins such as polyimide and polyamideimide; acrylic resins such as alkoxysilyl group-containing resins and poly(meth)acrylic acid; styrene-butadiene rubber (SBR); carboxymethyl cellulose; alginates such as sodium alginate and ammonium alginate; water-soluble cellulose ester cross-linked bodies; starch-acrylic acid graft polymers, etc. may be mentioned.

[0036] The shape of the positive electrode layer 252 may be rectangular. The thickness of the positive electrode layer 252 is not particularly limited and is, for example, in the range of 1 μm to 1 mm. The area of the positive electrode layer 252 may be smaller than that of the negative electrode layer 253. The content of each material in the positive electrode layer 252 is not particularly limited and may be appropriately set according to the intended battery performance. Note that the positive electrode layer 20 may contain materials other than the above-mentioned materials.

[0037] The negative electrode layer 253 contains a negative electrode active material. The negative electrode active material is not particularly limited and may be appropriately selected from known materials according to the target battery performance. For example, carbon such as graphite, artificial graphite, highly oriented graphite, mesocarbon microbeads, hard carbon, soft carbon, metal compounds, elements or their compounds capable of alloying with lithium, boron-added carbon, etc. may be mentioned. Examples of elements capable of alloying with lithium include silicon and tin.

[0038] The negative electrode layer 253 may optionally contain a conductive assistant. The conductive assistant is not particularly limited and may be appropriately selected from known materials according to the target battery performance. For example, it may be appropriately selected from the conductive assistants applicable to the positive electrode layer 252.

[0039] The negative electrode layer 253 may optionally contain a binder. The binder is not particularly limited and may be appropriately selected from known materials according to the target battery performance. For example, it may be appropriately selected from the binders applicable to the positive electrode layer 252.

[0040] The shape of the negative electrode layer 253 may be rectangular. The thickness of the negative electrode layer 253 is not particularly limited and is, for example, in the range of 1 μm to 1 mm. From the viewpoint of improving the output, the area of the negative electrode layer 253 may be made larger than that of the positive electrode layer 252. The content of each material in the negative electrode layer 253 is not particularly limited and may be appropriately set according to the target battery performance. Note that the negative electrode layer 253 may contain materials other than the above-described materials.

[0041] The method for manufacturing the bipolar electrode 250 is not particularly limited, and a known method may be adopted. For example, for example, the materials constituting the electrode layer (positive electrode layer 252 or negative electrode layer 253) may be mixed in a mortar or the like and pressed to obtain the electrode layer, and the obtained electrode layer may be disposed on each surface of the current collector 251. Alternatively, after mixing the materials constituting the electrode layer with a solvent to obtain a slurry, the slurry may be applied and dried on each surface of the current collector 251.

[0042] The electrolyte layer 260 is disposed between adjacent bipolar electrodes 250, between the bipolar electrode 250 and the end positive electrode 270, and between the bipolar electrode 250 and the end negative electrode 280.

[0043] When the electrolyte layer 260 is a liquid electrolyte layer, a separator is disposed between the electrodes, and then an electrolytic solution is supplied to the separator to obtain the electrolyte layer. The separator is mainly a porous sheet of polyolefin. The electrolytic solution is one in which a supporting salt is dissolved in a non-aqueous solvent. Examples of the non-aqueous solvent include carbonates, ethers, esters, etc. Examples of the supporting salt include LiPF6, LiBF4, lithium bis(fluorosulfonyl)imide (LiFSI), lithium bis(trifluoromethane)sulfonimide (LiTFSI), etc.

[0044] When the electrolyte layer is a solid electrolyte layer, a battery can be fabricated by disposing the solid electrolyte layer between the electrodes. The solid electrolyte layer contains a solid electrolyte. Further, the solid electrolyte layer may contain a binder. The solid electrolyte and the binder may be appropriately selected from the above-described solid electrolytes and binders.

[0045] The shape of the electrolyte layer 260 may be rectangular. The thickness of the electrolyte layer 260 is not particularly limited and is, for example, in the range of 1 μm to 1 mm.

[0046] The end positive electrode 270 has a current collector 251 and a positive electrode layer 252 disposed on one surface of the current collector 251. The end positive electrode 270 is disposed at one end in the stacking direction of the electrode laminate 18. Specifically, the end positive electrode 270 is stacked on the electrolyte layer 260 such that the positive electrode layer 252 of the end positive electrode 270 faces the negative electrode layer 253 of the bipolar electrode 250.

[0047] The end negative electrode 280 has a current collector 251 and a negative electrode layer 253 disposed on one surface of the current collector 251. The end negative electrode 280 is disposed at the other end in the stacking direction of the electrode laminate 18. Specifically, the end negative electrode 280 is stacked on the electrolyte layer 260 such that the negative electrode layer 253 of the end negative electrode 280 faces the positive electrode layer 252 of the bipolar electrode 250.

[0048] The method for manufacturing the end negative electrode 270 and the end negative electrode 280 is not particularly limited, and known methods may be appropriately employed. For example, a method similar to the method for manufacturing the bipolar electrode 250 described above may be adopted.

[0049] Fig. 5 shows a schematic cross-sectional view focusing on the first end portion 211 of the battery 200 after injection molding. As shown in Fig. 5, the resin R is disposed on the first end portion 211 including the first side surface 210 of the battery 200 by injection molding. Specifically, taking an example of the use of the mold of the present disclosure, for example, for a part of the battery covered with the resin R0 in advance (for example, for a part of the first side surface 210 covered with the resin R0), there is a method of additionally covering it with the resin R. Fig. 5 is a schematic cross-sectional view of the battery 200 after injection molding manufactured by such a method. Therefore, the resin R is formed so as to cover the end surface RP of the resin R0.

[0050] Also, the resin R0 is disposed so as to enter between adjacent bipolar electrodes 250 (current collectors 251) and covers the first side surface 210 with resin. The resin R0 is also disposed at the ends of each end surface (the first end surface 230 and the second end surface 240) of the battery 200. Further, it is disposed separated from the electrode layers (the positive electrode layer 252 and the negative electrode layer 253). In this way, the first end portion 211 of the battery 200 is covered with the resin R0, and further, the end surface RP of the resin R0 is covered with the resin R.

[0051] As described above, the injection molding mold of the present disclosure has been described using one embodiment. According to the injection molding mold of the present disclosure, variations in the thickness of the battery due to manufacturing tolerances can be absorbed, so the difficulty of the process of covering the battery side surface with resin by injection molding can be reduced, and productivity can be improved.

[0052] [Injection Molding Method] The injection molding method of the present disclosure is a method of covering the side surface of a battery with resin using the mold of the present disclosure. The injection molding method of the present disclosure will be described using one embodiment.

[0053] One embodiment is an injection molding method for covering an end portion of a battery 200 with resin using a mold 100. One embodiment includes an arrangement step S1, a fixing step S2, and an injection molding step S3. FIG. 6 shows a flowchart of the injection molding method of one embodiment.

[0054] <Arrangement step S1> The arrangement step S1 is a step of arranging the first end portion 211 of the battery 200 in the space 140 of the mold 100. At this time, the first end face of the battery 200 is supported by the fixing portion 151.

[0055] <Fixing step S2> The fixing step S2 is a step of fixing the battery 200 with the solid member 150 in a state where the first end portion 211 of the battery 200 is arranged in the space 140. As described in detail above, in the fixing step S2, the movable auxiliary portion 153 is moved in the longitudinal direction so that the second inclined portion 153a of the movable auxiliary portion 153 contacts along the first inclined portion 152a of the movable portion 152, thereby moving the movable portion 152 in the thickness direction. Then, the fixing member 150 sandwiches the first end face 230 and the second end face 240 of the battery 200 with the fixing portion 151 and the movable portion 152. Thereby, the battery 200 is fixed with the fixing member 150.

[0056] Here, in the fixing step S2, the pressure applied to the battery 200 from the movable portion 152 may be set to be equal to or less than a predetermined threshold value. Thereby, even when there is a variation in the thickness of the battery 200 due to manufacturing tolerances, the battery can be fixed with an appropriate pressure while suppressing breakage of the battery 200.

[0057] <Injection molding step S3> The injection molding process S3 injects the resin R into the space 140 and covers the first end portion 211 of the battery (when the first end portion 211 is already covered with the resin R0, the end face RP of the resin R0) with the resin R. In the injection molding process, the amount of resin injected into the space 140 may be adjusted according to the position of the movable part 152. By adjusting the amount of resin supplied to the space 140 according to the position of the movable part 152, even when there is a variation in the thickness of the battery 200, the first end portion 211 can be appropriately covered with the resin R.

[0058] By implementing the processes S1 to S3, one end portion of the battery 200 can be covered with resin. Further, by implementing the processes S1 to S3 for each end portion of the battery, each end portion of the battery 200 can be covered with resin.

[0059] As described above, the injection molding method of the present disclosure has been described using one embodiment. According to the injection molding method of the present disclosure, since the variation in the thickness of the battery due to manufacturing tolerances can be absorbed, the difficulty of the process of covering the side surface of the battery with resin by injection molding can be reduced, and the productivity can be improved.

Explanation of reference numerals

[0060] 100, 101, 102 Mold 110 Upper mold 120 Side mold 130 Lower mold 140 Space 150 Fixed member 151 Fixed part (protrusion) 152 Movable part 152a First inclined part 153 Movable auxiliary part 153a Second inclined part 154 Control part 200 Battery 210 First side surface 211 First end portion 220 Second side surface 221 Second end portion 230 First end face 240 Second end face 250 Bipolar electrode 251 Current collector 252 Positive electrode layer 253 Negative electrode layer 260 Separator 270 End positive electrode 280 End negative electrode R resin

Claims

1. A mold for injection molding used to cover the side surface of a battery with resin, a space capable of arranging a first end portion including the first side surface of the battery, and a fixing member capable of fixing the battery in a state where the first end portion of the battery is arranged in the space, the space is formed such that a second end portion arranged on the side opposite to the first end portion of the battery protrudes from the space when the first end portion of the battery is arranged in the space, the fixing member has a fixing portion and a movable portion, the fixing portion is configured to support a first end surface arranged on one side in the thickness direction of the battery, the movable portion is movable in the thickness direction and can press a second end surface arranged on the side opposite to the first end surface of the battery, the fixing member can fix the battery by sandwiching the first end surface and the second end surface of the battery with the fixing portion and the movable portion, the pressure applied to the battery from the movable portion is set to be equal to or less than a predetermined threshold value, Mold.

2. the fixing member has a movable auxiliary portion for moving the movable portion in the thickness direction, the movable portion has a first inclined portion that inclines in a direction perpendicular to the thickness direction on a surface in the thickness direction and opposite to the battery side, the movable auxiliary portion has a second inclined portion that inclines along the first inclined portion, the movable portion is moved in the thickness direction by moving the movable auxiliary portion so that the second inclined portion of the movable auxiliary portion contacts along the first inclined portion of the movable portion, The mold according to claim 1.

3. An injection molding method for covering the side surface of a battery with resin using the mold according to claim 1 or 2, an arranging step of arranging the first end portion of the battery in the space of the mold, A fixing step of fixing the battery with the solid member in a state where the first end portion of the battery is disposed in the space; An injection molding step of injecting the resin into the space and covering the first end portion of the battery with the resin, and In the fixing step, the pressure applied to the battery from the movable portion is set to be equal to or less than a predetermined threshold value, In the injection molding step, the amount of resin injected into the space is adjusted according to the position of the movable portion, An injection molding method.

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