JP2019160622A - Laminate type battery - Google Patents

Abstract

To cause a temperature-sensitive protective element to immediately perform a predetermined protective operation even when the temperature of a laminate cell suddenly rises.SOLUTION: A circuit board 20 is disposed facing a terrace portion 14a with the surface on which a heat generating element 22 is mounted facing the terrace portion 14a of a laminate cell 10a. A temperature sensitive protection element 27 is placed on the surface of the terrace portion 14a on the side where the circuit board 20 is disposed. The heat generating element 22 and the temperature sensitive protection element 27 are connected via a heat conductive member 25.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a laminate type battery including a laminate cell in which a power generation element is packaged with a laminate sheet and a temperature-sensitive protective element.

  A non-aqueous electrolyte battery typified by a lithium ion secondary battery is used as a power source for portable information terminals, portable game machines and the like because of its high energy density. In such applications, in order to satisfy the conflicting demands of miniaturization and large capacity, a laminated lithium ion secondary battery having a substantially rectangular plan view shape in which a thin plate-shaped power generation element is sheathed with a flexible laminate sheet. Secondary batteries (hereinafter referred to as “laminate cells”) are often used. The laminate cell includes a sealing region on which the laminate sheet is overlapped and sealed outside the power generation element. The seal region is along three or four sides of the substantially rectangular laminate cell. A positive electrode tab and a negative electrode tab connected to the power generation element are derived from one side of the laminate cell. Among the seal regions, the seal region along the side from which the positive electrode tab and the negative electrode tab are derived is called a terrace portion.

  A laminate type battery is formed by integrating a protective circuit component (safety circuit component) into a laminate cell (see, for example, Patent Document 1). As a protection circuit component, a temperature sensitive protection element (for example, a temperature breaker, a PTC element) is known. The temperature-sensitive protective element detects an abnormal temperature increase of the laminate cell and performs a predetermined protective operation (cuts or reduces the current).

JP 2006-114475 A

  The temperature-sensitive protective element is heated by the laminate cell whose temperature has risen, and performs a predetermined protective operation when the temperature-sensitive protective element reaches a predetermined temperature (operating temperature). The temperature of the temperature sensitive protective element rises with a delay in the temperature rise of the laminate cell. For this reason, when the temperature rise of the laminate cell is abrupt, the laminate cell reaches a dangerous temperature before the temperature-sensitive protective element reaches the operating temperature, and the protective operation by the temperature-sensitive protective element is not in time. there is a possibility.

  An object of the present invention is to provide a laminated battery with improved safety, in which the temperature-sensitive protective element can immediately perform a predetermined protective operation even when the temperature of the laminated cell is rapidly increased.

  A laminate type battery according to the present invention includes a laminate cell having a substantially rectangular plan view, in which a power generation element is covered with a flexible laminate sheet, a circuit board on which a heating element is mounted, a temperature sensitive protection element, Is provided. The laminate cell includes a seal region in which the laminate sheets are stacked and sealed. The seal region includes a terrace portion along a side from which a positive electrode tab and a negative electrode tab connected to the power generation element are derived. The circuit board is disposed to face the terrace portion with the surface on which the heat generating element is mounted facing the terrace portion. The temperature sensitive protection element is placed on the surface of the terrace portion on the side where the circuit board is disposed. The heat generating element and the temperature sensitive protection element are connected via a heat conductive member.

  According to the present invention, the temperature-sensitive protection element is warmed by the heating element via the heat conductive member. For this reason, when the temperature of the laminate cell rapidly increases, the temperature-sensitive protective element immediately reaches the operating temperature, and can perform a predetermined protective operation. In the laminate type battery of the present invention, since the heat conductive member can reliably perform a protective operation even when the temperature of the laminate cell rises suddenly, the possibility of smoking and ignition is reduced, and the safety is excellent.

FIG. 1 is an exploded perspective view of a laminated battery according to Embodiment 1 of the present invention. FIG. 2A is a perspective view of a laminate cell constituting the laminate type battery according to Embodiment 1 of the present invention. FIG. 2B is a perspective view showing a state in which the sealing region (ear part) along two opposing sides of the laminate cell of FIG. 2A is bent. FIG. 3 is a perspective view showing a process of manufacturing the laminated battery according to the first embodiment of the present invention. FIG. 4A is a perspective view of a laminated battery according to Embodiment 1 of the present invention. 4B is a side view of the laminated battery as viewed along the arrow 4B in FIG. 4A. FIG. 5A is a perspective view of a laminate cell constituting the laminate type battery according to Embodiment 2 of the present invention. FIG. 5B is a side view of the laminated cell according to the second embodiment of the present invention as seen along the arrow 5B in FIG. 5A. FIG. 6A is a perspective view showing a state in which a sealing region (ear portion) along two opposing sides of a laminate cell constituting a laminate type battery according to Embodiment 2 of the present invention is bent. FIG. 6B is a side view of the laminated cell according to the second embodiment of the present invention viewed along the arrow 6B in FIG. 6A. FIG. 7A is a perspective view of a laminated battery according to Embodiment 2 of the present invention. FIG. 7B is a side view of the laminated battery viewed along the arrow 7B in FIG. 7A.

  In the laminated battery of the present invention, the thermal conductivity of the thermal conductive member may be 100 to 1200 W / m · K. If the thermal conductivity is lower than this numerical range, the heat transfer characteristics from the heating element to the temperature-sensitive protection element will deteriorate, so the temperature-sensitive protection element will not reach the operating temperature before the laminate cell reaches the dangerous temperature. Things can happen. The greater the thermal conductivity, the better the heat transfer characteristics from the heating element to the temperature sensitive protection element. However, if the thermal conductivity is higher than the above numerical range, the temperature-sensitive protective element may operate even when the laminated battery is operating normally.

  The heating element may generate heat during charging / discharging of the laminate cell. Thereby, a temperature sensitive protection element can be warmed using the electric current at the time of charging / discharging.

  The heating element may be a fuse. Thereby, the fuse which is a protection element can be utilized also as a heat generating element for heating a temperature-sensitive protection element. This is advantageous in reducing the number of components mounted on a circuit board having a limited area while ensuring the safety of the battery.

  The temperature sensitive protection element may be a temperature breaker. Unlike a PTC element, the temperature breaker does not substantially lose current below the operating temperature. Further, even if the protection operation (interruption of current) is once performed, the protection operation is canceled when the temperature is lowered thereafter, so that the laminated battery can be used repeatedly.

  A cushion material capable of compressive deformation may be provided between the circuit board and the terrace portion. Thereby, it is possible to prevent the circuit board from abnormally approaching the terrace portion. This is advantageous in preventing the laminate sheet from being damaged.

  External wiring may be derived from the circuit board. In this case, the lead-out direction of the external wiring may be parallel to the longitudinal direction of the terrace portion.

  Below, this invention is demonstrated in detail, showing suitable embodiment. However, it goes without saying that the present invention is not limited to the following embodiments. Each drawing referred to in the following description shows simplified main members constituting an embodiment of the present invention for convenience of description. Therefore, the present invention can include any member not shown in the following drawings. Further, within the scope of the present invention, each member shown in the following drawings can be changed or omitted. In the drawings cited in the description of the respective embodiments, members corresponding to those shown in the drawings cited in the preceding embodiments are denoted by the same reference numerals as those in the drawings of the preceding embodiments. is there. About such a member, the overlapping description is abbreviate | omitted and you should consider the description of previous embodiment suitably.

(Embodiment 1)
FIG. 1 is an exploded perspective view of a laminated battery (hereinafter simply referred to as “battery”) 1 according to Embodiment 1 of the present invention. The battery 1 includes a laminate cell (hereinafter simply referred to as “cell”) 10 a and a circuit board 20.

  FIG. 2A is a perspective view of the cell 10a. The cell 10a has a substantially rectangular shape in plan view, and has a thin plate shape that is thinner than the vertical and horizontal dimensions of the substantially rectangular shape. In the cell 10a, a thin plate-shaped power generation element (not shown) having a substantially rectangular plan view shape is enclosed with an electrolyte in an exterior made of a laminate sheet 13. The power generation element includes a positive electrode in which a positive electrode mixture layer including a positive electrode active material is applied and formed on both surfaces of a predetermined region of the positive electrode current collector, and a negative electrode mixture layer including a negative electrode active material on both surfaces of the predetermined region of the negative electrode current collector Is an electrode laminate in which negative electrodes formed by coating are alternately laminated via separators. The type of the battery is not particularly limited, but a secondary battery, particularly a lithium ion secondary battery is preferable.

  The laminate sheet 13 is thinner than the power generation element and has flexibility. The laminate sheet 13 may be, for example, a multilayer sheet in which a heat-fusible resin layer (for example, a modified polyolefin layer) is laminated on the surface of the base layer made of aluminum or the like on the side facing the power generation element. One rectangular laminate sheet 13 is folded in half so as to sandwich the power generation element, is overlapped on the outside of the power generation element, and is sealed by a heat sealing method or the like. Seal regions 14a, 14b, and 14c where the laminate sheet 13 is sealed are along three sides of the substantially rectangular cell 10a. The seal regions 14a, 14b, and 14c are along a common plane. A substantially rectangular emboss 12 corresponding to the power generation element protrudes on one side with respect to the seal regions 14a, 14b, and 14c. As in the cell 10a, the cell in which the emboss 12 is protruded only on one side with respect to the seal regions 14a, 14b, and 14c is generally “single emboss type” or “ It is called “single-drawer type”. In the present invention, for convenience of explanation, in the single-embossed cell 10a, the surface on which the emboss 12 protrudes is referred to as the “front surface” of the cell 10a, and the opposite surface is referred to as the “back surface” of the cell 10a. Call it. The direction connecting the front surface and the back surface is referred to as “thickness direction” or “vertical direction”. A direction parallel to a plane common to the seal regions 14a, 14b, and 14c is referred to as a “horizontal direction”.

  A positive electrode tab 11p and a negative electrode tab 11n are led out from the seal region 14a. The positive electrode tab 11p and the negative electrode tab 11n have a strip shape and are orthogonal to the longitudinal direction of the seal region 14a (that is, a direction parallel to a pair of seal regions 14b and 14c connected to both ends of the seal region 14a). Extending along. The positive electrode tab 11p is made of, for example, an aluminum thin plate, and is electrically connected to a plurality of positive electrode current collectors (not shown) constituting the power generation element. The negative electrode tab 11n is made of, for example, a nickel thin plate or the like, and is electrically connected to a plurality of negative electrode current collectors (not shown) constituting the power generation element.

  In the present invention, the seal region 14a from which the positive electrode tab 11p and the negative electrode tab 11n are derived is referred to as a “terrace portion”. Further, the seal regions 14b and 14c connected to both ends of the terrace portion 14a are referred to as “ear portions”. The first ear portion 14b and the second ear portion 14c extend along a side perpendicular to the side of the cell 10a along which the terrace portion 14a is aligned. In order to reduce the outer dimension of the cell 10a, as shown in FIG. 2B, the ear portions 14b and 14c are bent at a substantially right angle with respect to the terrace portion 14a on the same side as the emboss 12. The bent ear portions 14b and 14c are fixed to the side surface of the emboss 12 using a double-sided adhesive tape or the like. The terrace portion 14a is surrounded in three directions by the emboss 12 and the ear portions 14b and 14c.

  Returning to FIG. 1, the circuit board 20 is an elongated thin plate-like object, and has a longitudinal dimension substantially the same as or shorter than the terrace portion 14 a. A heating element 22 is mounted on the first surface of the circuit board 20. The heating element 22 self-heats due to the current during charging / discharging of the cell 10a. In the first embodiment, the heat generating element 22 is a heat generating protective element that performs a predetermined protection operation when a predetermined current is reached, and is specifically a fuse (current fuse). The fuse generates heat when a current flows through itself. When an overcurrent occurs due to an external short circuit, etc., the fuse element in the fuse generates heat and blows to interrupt the circuit. Once the protection operation (current interruption) is performed, the state before the operation is not restored. A fuse normally used as a laminate type battery can be used as the heating element 22.

  A protective circuit component (safety circuit component) 23 made of electronic components such as FET elements is further mounted on the first surface of the circuit board 20, and a positive input terminal 21p and a negative input terminal 21n are provided.

  The external wiring 24 is connected to a terminal (not visible in FIG. 1) provided on the first surface of the circuit board 20. The sealing portion 24 b seals and insulates an electrical connection portion between a terminal (not shown) provided on the first surface of the circuit board 20 and the external wiring 24. The sealing portion 24b is made of a known glue, an insulating resin, or an adhesive. The external wiring 24 is connected in the vicinity of the end of one side (first ear portion 14b side) in the longitudinal direction of the circuit board 20, and is parallel to the longitudinal direction of the terrace portion 14a (or the circuit board 20) from the circuit board 20. Has been derived. A connector 24 a is provided at the tip of the external wiring 24. The connector 24a is connected to a connector (device side connector) provided in a device in which the battery 1 is incorporated. The battery 1 can be charged / discharged via the external wiring 24. The external wiring 24 is an assembly of a plurality of flexible cables (three in the first embodiment). Each cable constituting the external wiring 24 includes a conductive wire (conductive wire) such as copper and an insulating material (insulating coating) such as polyurethane that covers the conductive wire, and is also called a coated wire. . The external wiring 24 of the present embodiment is a flat cable in which insulating coatings of a plurality of cables are fused and connected to each other. The type of the plurality of cables is not particularly limited, and may include, for example, a positive cable, a negative cable, a temperature detection cable for detecting the temperature of the laminate cell 10a, and the like. The number of cables constituting the external wiring 24 and the function of each cable are not limited to this embodiment, and can be arbitrarily changed. The connector 24a may be omitted.

  The battery 1 further includes a temperature sensitive protection element 27. The temperature-sensitive protective element 27 includes an element main body that performs a predetermined protective operation when the temperature-sensitive protective element 27 reaches a predetermined temperature, and a first lead 27a and a second lead 27b that are led out from the element main body in opposite directions. . In the first embodiment, a temperature breaker is used as the temperature sensitive protection element 27. The protection operation of the temperature breaker is a current interruption, and once the protection operation is performed, the protection operation (current interruption) is canceled when the temperature is lowered thereafter. The first lead 27a and the second lead 27b are strip-like thin plates made of conductive metal. The first lead 27a is connected to the positive electrode tab 11p of the cell 10a. The second lead 27 b is connected to the positive electrode input terminal 21 p provided on the first surface of the circuit board 20 via the conductive tab 28. The conductive tab 28 is a strip-shaped thin plate made of a conductive metal (for example, nickel).

  The negative electrode tab 11n of the cell 10a is connected to a negative electrode input terminal 21n provided on the first surface of the circuit board 20.

  A heat conductive member 25 is provided between the heat generating element 22 and the temperature sensitive protection element 27. The heat conductive member 25 has both heat conductivity and insulation. The thermal conductivity of the thermal conductive member 25 is not limited, but is 100 W / m · K or more, more preferably 200 W / m · K or more, preferably 1200 W / m · K or less, and more preferably 1000 W / m · K or less. . Although the structure of the heat conductive member 25 is not limited, for example, a metal layer having heat conductivity such as copper or aluminum is used as an insulating resin layer (for example, polyester resin such as PET, acrylic resin, silicon resin). ). As an example of the heat conductive member 25, a “heat spreader tape” manufactured by 3M Japan Ltd. can be exemplified. The heat generating element 22 and the temperature sensitive protection element 27 are connected via the heat conductive member 25 (see FIG. 4B described later). Although there is no restriction | limiting in the method of fixing the heat conductive member 25 to the heat generating element 22 and the temperature sensitive protection element 27, For example, a double-sided adhesive tape or an adhesive agent can be used. In the first embodiment, the heat conductive member 25 has a substantially rectangular parallelepiped shape (or block shape) having a thickness corresponding to the distance between the heating element 22 and the temperature sensitive protection element 27. A plurality of sheet-like heat conductive members 25 may be laminated so that the heat conductive member 25 has a desired thickness.

  Two cushion members 26 a and 26 b are provided between the terrace portion 14 a and the circuit board 20. The cushion members 26a and 26b have a substantially rectangular parallelepiped shape and are made of an elastic body that can be compressed and deformed. Although there is no restriction | limiting as cushioning material 26a, 26b, The material which deform | transforms easily when external force is applied like a foam material, sponge, etc., and restores to an initial shape when external force is removed can be used. The cushion materials 26a and 26b preferably have insulating properties. The cushion materials 26a and 26b may be, for example, urethane foam, polyethylene sponge, or the like. As an example, “PORON (registered commerce)” manufactured by Roger Sinoac Co., Ltd. can be exemplified. Preferably, a double-sided adhesive tape or an adhesive is applied to the upper and lower surfaces of the cushion materials 26a and 26b.

  FIG. 3 shows a process for manufacturing the battery 1. The temperature sensitive protection element 27 is placed on the same surface as the side from which the emboss 12 of the terrace portion 14a protrudes. A method for fixing the temperature-sensitive protective element 27 to the terrace portion 14a is not limited, but for example, a double-sided pressure-sensitive adhesive tape or an adhesive can be used. A heat conductive member 25 is placed on the temperature sensitive protection element 27 (particularly, the element main body). The positive electrode tab 11p is bent in a substantially “U” shape. The negative electrode tab 11n and the conductive tab 28 extend parallel to each other between the cell 10a and the circuit board 20. The cushion materials 26a and 26b are attached to the same surface as the side from which the emboss 12 of the terrace portion 14a protrudes. The first cushion material 26a is disposed in the vicinity of the first ear portion 14b, and the second cushion material 26b is disposed in the vicinity of the second ear portion 14c.

  From the state of FIG. 3, the temperature-sensitive protective element 27 of the terrace portion 14a is placed on the first surface of the circuit board 20 (the surface on which the heating element 22 and the protective circuit component 23 are mounted and the external wiring 24 is connected). The circuit board 20 is opposed to the terrace portion 14a so as to face the surface. The negative electrode tab 11n and the conductive tab 28 are bent or bent so as to have a substantially “U” shape when viewed along the longitudinal direction of the terrace portion 14a.

  FIG. 4A is a perspective view of the battery 1 in which the circuit board 20 is overlaid on the terrace portion 14a. The second surface of the circuit board 20 (the surface opposite to the surface on which the heating element 22 and the protection circuit component 23 are mounted and the external wiring 24 is connected) is in the thickness direction with respect to the top surface of the emboss 12 of the cell 10a. It is in almost the same position. The flat second surface of the circuit board 20 and the top surface of the emboss 12 constitute a common plane. Both surfaces in the vertical direction of the battery body 1a including the cell 10a and the circuit board 20 are substantially flat surfaces with substantially no protrusion. The battery body 1a may be packaged with an exterior sheet (not shown) as necessary. Although an exterior sheet is not restrict | limited, For example, it consists of resin or paper which has insulation.

  4B is a side view of the battery 1 as viewed along the arrow 4B in FIG. 4A. The heat generating element 22 and the temperature sensitive protection element 27 are opposed to each other in the thickness direction, and the heat conductive member 25 is disposed therebetween. The heat conductive member 25 connects the heat generating element 22 and the temperature sensitive protection element 27.

  The protection operation when the battery 1 is abnormal will be described.

  The heating element 22 self-heats due to a current flowing when the battery 1 (or the cell 10a) is charged / discharged. When an overcurrent flows due to an external short circuit or the like, the heating element 22 generates heat rapidly. When the heat generating element 22 reaches a predetermined current, the heat generating element 22 performs a predetermined protective operation (current interruption in the first embodiment).

  The temperature-sensitive protection element 27 detects an abnormal temperature rise of the cell 10a due to overcharge or the like and performs a predetermined protection operation (cuts off current in the first embodiment). It can be seen from the cell 10a that the temperature sensitive protection element 27 is placed on the terrace portion 14a and that the positive electrode tab 11p of the cell 10a is connected to the first lead 27a of the temperature sensitive protection element 27. It is advantageous for facilitating heat transfer to the temperature protective element 27 and improving the detection sensitivity of the temperature sensitive protective element 27 with respect to the temperature rise of the cell 10a.

  In order for the temperature-sensitive protection element 27 to perform a predetermined protection operation, it is necessary to heat the temperature-sensitive protection element 27 to a temperature at which the temperature-sensitive protection element 27 performs the protection operation (this is referred to as “operation temperature”). Unlike the battery 1 of the first embodiment, in a battery in which the thermal conductive member 25 is not provided (this battery is referred to as a “comparative example”), the heat of the abnormally temperature-increased cell 10 a Heat is transferred to the temperature-sensitive protective element 27 via the. When the temperature rise of the cell 10a is abrupt, even if the cell 10a reaches a dangerous temperature, a situation may occur in which the temperature sensitive protection element 27 has not yet reached the operating temperature. Such a rapid temperature rise of the cell 10a occurs, for example, when the cell 10a is overcharged due to, for example, inactivation (failure) of the voltage control circuit of the battery 1 charger.

  On the other hand, in the first embodiment, the heat generating element 22 and the temperature sensitive protection element 27 are connected via the heat conductive member 25. During charging / discharging of the battery 1, the heating element 22 always generates heat. The heat of the heat generating element 22 is transferred to the temperature sensitive protection element 27 through the heat conductive member 25. Therefore, in a state where the battery 1 is charged and discharged, the temperature sensitive protection element 27 is always warmed by the heating element 22. The temperature of the temperature-sensitive protection element 27 at this time is higher than that of the comparative example in which the heat conductive member 25 is not provided and lower than the operating temperature of the temperature-sensitive protection element 27. For this reason, when the temperature of the cell 10a suddenly rises, the temperature-sensitive protection element 27 immediately reaches the operating temperature by a slight heat transfer through the terrace portion 14a and the positive electrode tab 11p, and can perform a predetermined protective operation. it can. The battery 1 of the first embodiment is excellent in safety because the possibility that the protection operation by the temperature-sensitive protection element is not in time even when the temperature of the cell 10a suddenly rises is reduced.

  Since the heat conductive member 25 has an insulating property, for example, even if the heat conductive member 25 contacts the positive electrode tab 11p or the first lead 27a and the conductive tab 28, a short circuit does not occur.

  The external wiring 24 is connected to the first surface of the circuit board 20 (the surface facing the terrace portion 14a). The external wiring 24 is connected to the vicinity of one end (first ear portion 14b side) in the longitudinal direction of the circuit board 20 having a long and narrow rectangular shape in plan view, and the terrace portion from the first ear portion 14b side. 14a (or circuit board 20) is led out in parallel to the longitudinal direction. This can be advantageous in simplifying the handling of the external wiring 24 in the device in which the battery 1 is incorporated and reducing the size of the device.

  Cushion materials 26a and 26b are interposed between the circuit board 20 and the terrace portion 14a. The cushion materials 26a and 26b have the following actions.

  First, the cushion members 26a and 26b prevent the circuit board 20 from abnormally approaching the terrace portion 14a. Unlike the first embodiment, when the cushion materials 26a and 26b are not provided, for example, in the process of manufacturing the battery 1, the negative electrode tab 11n and the conductive tab 28 are bent so that the circuit board 20 faces the terrace portion 14a. When the battery 1 is subjected to an impact due to dropping or the like, the circuit board 20 may abnormally approach the terrace portion 14a. This causes a collision between the external wiring 24 and the first ear part 14b, and a collision between the circuit board 20 (including a mounting component mounted on the circuit board 20) and the terrace part 14a. As a result, the laminate sheet 13 constituting the first ear portion 14b and the terrace portion 14a is damaged, and leakage of the electrolyte due to the tear of the laminate sheet 13, intrusion of moisture into the cell 10a, and short circuit in the cell 10a occur. sell. Further, the insulation coating of the external wiring 24 may be damaged by the first ear portion 14b. In the first embodiment in which the cushion materials 26a and 26b are provided, the above-described collision can be avoided.

  Secondly, the cushion materials 26 a and 26 b facilitate the manufacture of the battery 1. When the double-sided pressure-sensitive adhesive tape or adhesive is applied to the upper and lower surfaces of the cushion materials 26a and 26b, once the circuit board 20 is superimposed on the terrace portion 14a via the cushion materials 26a and 26b as shown in FIGS. 4A and 4B, The circuit board 20 and the terrace portion 14a are connected via the cushion materials 26a and 26b. The cushion members 26a and 26b resist the elastic repulsive force of the negative electrode tab 11n and the conductive tab 28 that try to separate the circuit board 20 from the terrace part 14a, and prevent the circuit board 20 from separating from the terrace part 14a. For this reason, the handleability of the battery 1 in the subsequent manufacturing process of the battery 1 (for example, the process of covering the battery body 1a with the exterior sheet) is improved, and the manufacturing of the battery 1 is facilitated.

  Preferably, the first cushion material 26a presses the external wiring 24 toward the circuit board 20 so that the external wiring 24 does not hang down toward the first ear portion 14b. This is advantageous in preventing the external wiring 24 from colliding with the tip of the first ear portion 14b. The collision between the external wiring 24 and the first ear portion 14b may cause the above-described damage to the laminate sheet 13 and the insulation coating of the external wiring 24. The first cushion material 26a is advantageous in preventing such a situation from occurring.

  In addition, the number and arrangement | positioning of the cushioning material provided in the battery 1 are not limited to said embodiment, It can change suitably.

(Embodiment 2)
FIG. 5A is a perspective view of a laminate cell (hereinafter simply referred to as “cell”) 10b constituting a laminate type battery 2 (see FIGS. 7A and 7B described later) according to Embodiment 2 of the present invention. FIG. 5B is a side view of the cell 10b as viewed along the arrow 5B in FIG. 5A. In the cell 10b of the second embodiment, substantially rectangular embosses 12a and 12b corresponding to the power generation elements protrude on both sides in the thickness direction with respect to the seal regions 14a, 14b and 14c. The protrusion height of the first emboss 12a protruding to one side with respect to the seal regions 14a, 14b, and 14c may be the same as or different from the protrusion height of the second emboss 12b protruding to the other side. It may be. A cell in which embosses 12a and 12b protrude on both sides with respect to the seal regions 14a, 14b and 14c, such as the cell 10b, is generally referred to as “both embossed molds” or the molded shape of the laminate sheet 13 as “both It is called “aperture type”. A direction connecting the first emboss 12a and the second emboss 12b is referred to as “thickness direction” or “vertical direction”.

  As shown in FIGS. 6A and 6B, as in the first embodiment, in order to reduce the outer dimension of the cell 10b, the ear portions 14b and 14c are substantially the same as the first emboss 12a and are substantially the same as the terrace portion 14a. It can be bent at right angles. The bent ear portions 14b and 14c are fixed to the side surface of the first emboss 12a using a double-sided adhesive tape or the like. The terrace portion 14a is surrounded in three directions by the first emboss 12a and the ear portions 14b and 14c.

  FIG. 7A is a perspective view of the laminated battery (hereinafter simply referred to as “battery”) 2 as viewed from the first emboss 12a side. FIG. 7B is a side view of the battery 2 as viewed along the arrow 7B in FIG. 7A. The circuit board 20 is disposed on the side where the first emboss 12a protrudes from the terrace portion 14a, with the first surface thereof facing the terrace portion 14a and facing the terrace portion 14a. The temperature sensitive protection element 27 is placed on the surface of the terrace portion 14a on the side where the circuit board 20 is disposed. The heat generating element 22 and the temperature sensitive protection element 27 are connected via the heat conductive member 25. Since the distance between the heat generating element 22 and the temperature sensitive protection element 27 is narrow, the heat conductive member 25 is thinner than the first embodiment.

  The battery 2 of the second embodiment uses the battery 1 of the first embodiment (FIG. 4A, FIG. 4) except that both embossed cells 10 b whose ears 14 b and 14 c are bent on the same side as the first emboss 12 a are used. (See 4B). The description of the first embodiment is also appropriately applied to the second embodiment.

  The above-described first and second embodiments are merely examples. The present invention is not limited to the first and second embodiments, and can be changed as appropriate.

  In the present invention, the heat generating element 22 and the temperature sensitive protective element 27 are connected via the heat conductive member 25 so that heat is transferred from the heat generating element 22 to the temperature sensitive protective element 27 via the heat conductive member 25. Is done. It is arbitrary how the heat conductive member 25 connects the heat generating element 22 and the temperature sensitive protection element 27. In the first and second embodiments, the substantially rectangular parallelepiped heat conductive member 25 having the same thickness as the distance between the heat generating element 22 and the temperature sensitive protective element 27 is replaced with the heat generating element 22 and the temperature sensitive protective element. 27. However, the heat conductive member 25 of the present invention is not limited to this. For example, the heat conductive member 25 may be a thin sheet having flexibility or deformability. In this case, one end of the sheet may be connected to the heating element 22 and the other end may be connected to the temperature-sensitive protection element 27. A double-sided pressure-sensitive adhesive tape or an adhesive can be used to connect the sheet to the heating element 22 and the temperature-sensitive protection element 27. In this configuration, even when the distance between the heating element 22 and the temperature-sensitive protection element 27 is different for each battery, or when the heating element 22 and the temperature-sensitive protection element 27 are not opposed to each other in the thickness direction. The heating element 22 and the temperature sensitive protection element 27 can be connected via the sheet by appropriately bending or bending the sheet.

  As the temperature-sensitive protective element 27, any element that performs a predetermined protective operation when a predetermined high temperature is reached can be used. In the first and second embodiments, the temperature sensitive protection element 27 is a temperature breaker, but the present invention is not limited to this. For example, as the temperature-sensitive protective element 27, a PTC element that increases resistance due to temperature rise and decreases current may be used.

  In the first and second embodiments, the heat generating element 22 is a heat generating protective element (for example, a current fuse). As a result, the heat-generating protective element can also be used as the heat-generating element 22 for heating the temperature-sensitive protective element 27. This is advantageous in reducing the number of components mounted on the circuit board 20 having a limited area while ensuring the safety of the battery. However, in the present invention, the heat generating element 22 may be an element that does not perform a protection operation in the event of an abnormality, and that self-heats simply due to current during charging and discharging.

  In the first and second embodiments, the external wiring 24 is derived from the side of the first ear portion 14b close to the negative electrode tab 11n of the two ear portions 14b and 14c. However, the external wiring 24 may be derived from either side of the ear portions 14b and 14c. The external wiring 24 does not need to be led out from the circuit board 20 in parallel with the longitudinal direction of the terrace portion 14a (or the circuit board 20). For example, the external wiring 24 extends from the circuit board 20 to the longitudinal direction of the terrace section 14a (or the circuit board 20). Alternatively, it may be led out substantially perpendicularly (that is, parallel to the longitudinal direction of the ear portions 14b and 14c). The battery of the present invention may not include the external wiring 24. For example, the circuit board 20 may be provided with electrical contacts for a device in which the battery 1 is incorporated.

  The connection path between the positive electrode tab 11p and the negative electrode tab 11n of the cell and the circuit board 20 is not limited to the first and second embodiments. For example, the positive electrode tab 11p and the first lead 27a of the temperature-sensitive protection element 27 may be connected via another conductive tab. The temperature sensitive protection element 27 may be provided between the negative electrode tab 11n and the negative electrode input terminal 21n. The arrangement of the positive electrode tab 11p and the negative electrode tab 11n may be opposite to those of the first and second embodiments.

  The arrangement of the mounting components (the heating element 22, the protection circuit component 23, the sealing portion 24b), the positive input terminal 21p, the negative input terminal 21n, and the like on the circuit board 20 can be arbitrarily changed. Two or more protection circuit components 23 may be mounted on the circuit board 20. Arbitrary components not shown in the first and second embodiments can be mounted on the circuit board 20, or an arbitrary circuit can be formed.

  The position, number, size, and the like of the cushion materials 26a and 26b can be arbitrarily set. In the present invention, the cushion material can be omitted.

  The ear portions 14b and 14c of the cells 10a and 10b do not have to be bent at substantially right angles to the terrace portion 14a. In both the embossed cells 10b, any one or both of the ear portions 14b and 14c may be bent at a substantially right angle with respect to the terrace portion 14a on the same side as the second emboss 12b.

  The field of application of the present invention is not limited, but can be widely used as a battery built in a portable electronic device that requires a high volumetric energy density. For example, it can be preferably used as a small and large-capacity battery built in an electronic device such as a mobile phone, a smartphone, a tablet terminal, a notebook computer, an electronic dictionary, an electronic book, or a portable game machine.

1, 2 Laminate type battery 10a, 10b Laminate cell 11p Positive electrode tab 11n Negative electrode tab 12, 12a, 12b Emboss 13 Laminate sheet 14a Terrace part (seal area)
14b First ear (seal area)
14c Second ear (seal area)
20 Circuit board 22 Heating element (fuse)
23 Protection circuit component 24 External wiring 25 Thermally conductive members 26a and 26b Cushion material 27 Temperature sensitive protection element (temperature breaker)

Claims (7)

A laminate-type battery comprising a laminate cell having a substantially rectangular plan view, in which a power generation element is packaged with a flexible laminate sheet, a circuit board on which a heating element is mounted, and a temperature-sensitive protection element. And
The laminate cell includes a seal region where the laminate sheet is overlaid and sealed,
The seal region includes a terrace portion along a side from which a positive electrode tab and a negative electrode tab connected to the power generation element are derived,
The circuit board is disposed facing the terrace portion with the surface on which the heating element is mounted facing the terrace portion,
The temperature sensitive protection element is placed on the surface of the terrace portion on the side where the circuit board is disposed,
A laminate type battery, wherein the heat generating element and the temperature sensitive protection element are connected via a heat conductive member.   The laminate type battery according to claim 1, wherein the thermal conductivity of the thermal conductive member is 100 to 1200 W / m · K.   The laminate-type battery according to claim 1, wherein the heating element generates heat during charging / discharging of the laminate cell.   The laminate type battery according to any one of claims 1 to 3, wherein the heating element is a fuse.   The laminate type battery according to any one of claims 1 to 4, wherein the temperature-sensitive protective element is a temperature breaker.   The laminate type battery according to any one of claims 1 to 5, wherein a cushioning material capable of compressive deformation is provided between the circuit board and the terrace portion.   The laminated battery according to any one of claims 1 to 6, wherein external wiring is led out from the circuit board, and a leading direction of the external wiring is parallel to a longitudinal direction of the terrace portion.

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