Energy storage devices, energy storage modules, and mobile units
The energy storage device addresses sealing issues by using a dual-packaging material and fastening mechanism to withstand increased pressure and thermal stress, ensuring reliable operation during rapid charging.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- DAI NIPPON PRINTING CO LTD
- Filing Date
- 2024-12-26
- Publication Date
- 2026-07-08
AI Technical Summary
Conventional power storage devices face issues with sealing performance degradation due to increased internal pressure and thermal runaway during rapid charging, leading to potential unsealing, smoke generation, and ignition.
An energy storage device design featuring an electrode portion with alternately stacked positive and negative electrode plates, an outer casing with dual packaging materials bonded by a sealing band and fastening member, and a fastening mechanism to maintain sealing under high pressure and thermal stress.
The design maintains sealing performance even under increased internal pressure and during thermal runaway, preventing unsealing and ensuring safety.
Smart Images
Figure 2026114506000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a power storage device, a power storage module including the power storage device, and a moving body including the power storage module.
Background Art
[0002] A conventional power storage device is disclosed in Patent Document 1. In this power storage device, a power storage element is enclosed in an exterior member. The power storage element has a configuration in which a positive electrode plate and a negative electrode plate are arranged to face each other via a separator, and an electrolyte is disposed between the positive electrode plate and the negative electrode plate. The power storage device has a configuration in which the power storage element is housed inside an exterior material formed of a resin film including a metal layer or a barrier layer. By covering the power storage element and the electrolyte with the resin film and sealing the outer edge portion, the power storage element is sealed by the exterior material.
[0003] In addition, a plurality of power storage devices having such a configuration are arranged side by side, and the power storage devices are connected in parallel or in series, and a power storage module housed in a module, a pack, or directly in a moving body is also used.
Prior Art Documents
Patent Documents
[0004]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0005] In recent years, the power storage capacity of power storage devices has been increasing. Along with the increase in the power storage capacity, the internal pressure acting on the exterior material due to gas generation, particularly during rapid charging of the power storage element, tends to increase. When the internal pressure rapidly increases, an excessive force acts on the exterior material sealing portion, which may lead to a decrease in the sealing performance and local unsealing, causing problems in the power storage device. In addition, thermal runaway may occur in battery failures such as internal short circuits. When thermal runaway occurs, the battery temperature rapidly rises, which may lead to unsealing, smoke generation, and ignition.
[0006] The present invention aims to provide an energy storage device that maintains its sealing performance even when internal pressure and temperature rise due to repeated rapid charging, and also maintains its sealing performance even when thermal runaway occurs in the event of an abnormality such as an internal short circuit or nail penetration. [Means for solving the problem]
[0007] An exemplary energy storage device of the present invention comprises an electrode portion in which positive electrode plates and negative electrode plates are alternately stacked via an intermediate member; an outer casing member having a first packaging material and a second packaging material that cover the electrode portion from both outer sides in the stacking direction of the electrode portion; and terminal portions electrically connected to the positive electrode plate and the negative electrode plate, respectively. The outer casing member has a housing portion for housing the electrode portion and a sealing band portion connected to at least a part of the outer edge of the housing portion so that the first packaging material and the second packaging material are directly or indirectly bonded together. The sealing band portion has a fastening portion that applies a fastening force in the stacking direction to the first packaging material and the second packaging material by a fastening member that fastens through the first packaging material and the second packaging material. [Effects of the Invention]
[0008] According to the present invention, it is possible to provide an energy storage device that maintains sealing performance even when the internal pressure rises due to repeated rapid charging, and also maintains sealing performance even when thermal runaway occurs due to internal short circuits, nail penetration, etc. [Brief explanation of the drawing]
[0009] [Figure 1] Figure 1 is a front view of the energy storage device. [Figure 2] Figure 2 is a cross-sectional view of the energy storage device shown in Figure 1, cut along the line II-II. [Figure 3] Figure 3 is an enlarged cross-sectional view of the device shown in Figure 1, cut along line III-III. [Figure 4] Figure 4 is a cross-sectional view showing the laminated structure of the resin sheet. [Figure 5]Figure 5 is an exploded perspective view of an energy storage device. [Figure 6] Figure 6 is a perspective view of the energy storage module. [Figure 7] Figure 7 is a side view of the electric vehicle. [Figure 8] Figure 8 is a plan view of the electric vehicle. [Figure 9] Figure 9 is a front view of the first modified energy storage device. [Figure 10] Figure 10 is a front view of the second modified energy storage device. [Figure 11] Figure 11 is a cross-sectional view of the energy storage device shown in Figure 10, cut along the line XI-XI. [Figure 12] Figure 12 is a plan view of the terminal section. [Figure 13] Figure 13 is a front view of the third modified energy storage device. [Modes for carrying out the invention]
[0010] The following describes an energy storage device according to one embodiment of the present invention with reference to the drawings. However, the scope of the present invention is not limited to the following embodiments and can be arbitrarily modified within the scope of the technical concept of the present invention.
[0011] In this specification, the energy storage device 1 is defined as having the Y-direction as vertical, the X-direction as horizontal, and the Z-direction as front-back, based on the state shown in Figures 1 and 2. In the energy storage device 1, the Z-direction is the front-back direction. These directions are assigned for convenience to facilitate explanation and do not represent the actual directions of use.
[0012] <Energy Storage Device 1> Figure 1 is a front view of the energy storage device 1. Figure 2 is a cross-sectional view of the energy storage device 1 shown in Figure 1, taken along line II-II. Figure 3 is an enlarged cross-sectional view of the energy storage device 1 shown in Figure 1, taken along line III-III.
[0013] As shown in Fig. 1, in a front view, the power storage device 1 has a rectangular shape with the X direction being the longitudinal direction. As shown in Figs. 1, 2, and 3, the power storage device 1 includes an exterior member 10, a power storage element 20, and a terminal portion 30. The power storage device 1 has a configuration in which the power storage element 20 is accommodated in an accommodation portion 11 provided in the exterior member 10, such as a primary battery, a secondary battery, an electric double layer capacitor (including EDLC), etc. Examples of the power storage device 1 include a lithium ion battery, a lithium ion polymer battery, a lithium ion all-solid-state battery, a lithium ion capacitor, a lead storage battery, a nickel hydrogen storage battery, a nickel cadmium storage battery, a nickel iron storage battery, a nickel zinc storage battery, a silver oxide zinc storage battery, a metal air battery, a polyvalent cation battery, etc.
[0014] <Power storage element 20> In the power storage device 1, the power storage element 20 is accommodated in the accommodation portion 11 together with an electrolyte. The power storage element 20 includes a positive electrode plate 21, a negative electrode plate 22, and a separator 23. In the power storage element 20, the positive electrode plate 21 and the negative electrode plate 22 are oppositely arranged via an insulator separator 23. In the power storage element 20, a plurality of sheets of the positive electrode plate 21, separator 23, negative electrode plate 22, and separator 23 are laminated in the Z direction in multiple stages to form the power storage element 20. In the power storage device 1, the power storage device 1 is accommodated in the accommodation portion 11 together with the electrolyte such that the direction in which the positive electrode plate 21 and the negative electrode plate 22 are laminated is the Z direction of the power storage device 1.
[0015] In this embodiment, an electrolytic solution, which is a liquid electrolyte, is used as the electrolyte and is filled inside the accommodation portion 11. A solid electrolyte or a gel-like electrolyte may be used as the electrolyte. The separator 23 is an example of an intermediate member disposed between the positive electrode plate 21 and the negative electrode plate 22. Also, when a solid electrolyte is used as the electrolyte, the solid electrolyte is the intermediate member and there is no separator.
[0016] <Terminal portion 30> The terminal section 30 has a positive terminal 31 and a negative terminal 32. The positive terminal 31 is connected to the positive plate 21, and the negative terminal 32 is connected to the negative plate 22. The positive terminal 31 and the negative terminal 32 are conductive. As shown in Figures 1 and 2, the positive terminal 31 and the negative terminal 32 pass through the first sealing portion 121 of the sealing band 12 and protrude to the outside of the exterior member 10. In the energy storage device 1, the positive terminal 31 and the negative terminal 32 are input / output terminals for charging and discharging the energy storage element 20. In a front view, in the energy storage device 1, the positive terminal 31 and the negative terminal 32 protrude outward from both ends in the X direction.
[0017] <Exterior component 10> The first packaging material 141 and the second packaging material 142 of the exterior component 10 are composed of a resin sheet 40 having at least one insulating layer. Figure 4 is a cross-sectional view showing the laminated structure of the resin sheet 40. As shown in Figure 4, the resin sheet 40 is formed by sequentially laminating at least a base layer 41, a barrier layer 42, and a heat-adhesive resin layer 43. The thickness of the resin sheet 40 is preferably 50 μm or more considering the strength of the exterior component 10, and preferably 400 μm or less considering the weight reduction of the energy storage device 1. The thicker the barrier layer 42, the higher the strength and thermal conductivity. Therefore, if the strength and thermal conductivity of the exterior component 10 are required even if the weight of the energy storage device 1 increases, the thickness of the resin sheet 40 may be 1 mm to 2 mm or more.
[0018] The base layer 41 is insulating and is formed from a resin film such as nylon, polyester, or polyethylene terephthalate. The thickness of the base layer 41 is, for example, 10 μm to 75 μm. To improve heat resistance, it is more desirable to form the base layer 41 from a uniaxially oriented film or a biaxially oriented film. The thicker the base layer 41, the less favorable the thermal conductivity in the Z direction becomes. For example, if sufficient thermal conductivity can be ensured by the barrier layer 42, the thickness of the base layer 41 may be about 50 μm.
[0019] Furthermore, to improve pinhole resistance, insulation, etc., multiple resin films of different materials may be laminated to form the base layer 41. In this case, the multiple resin films are bonded together with a polyurethane-based, acrylic-based, silicone-based adhesive or an acid-modified resin. In this embodiment, the resin sheet 40 is formed by laminating polyethylene terephthalate (thickness 12 μm) and nylon (thickness 15 μm) with an adhesive (thickness 4 μm).
[0020] The barrier layer 42 prevents the intrusion of water vapor, oxygen, light, etc. As the barrier layer 42, for example, metal foil such as aluminum, aluminum alloy, stainless steel, titanium, iron, or high-strength steel can be used. The thickness of the barrier layer 42 is formed to be, for example, 10 μm or more and 500 μm or less. The base layer 41 and the barrier layer 42 are bonded together with a polyurethane-based, acrylic-based, silicone-based adhesive or an acid-modified resin, etc. (not shown). In the resin sheet 40 of this embodiment, the barrier layer 42 is formed of aluminum foil with a thickness of 40 μm.
[0021] The heat-adhesive resin layer 43 can be any resin that has heat-adhesive properties, and is formed from, for example, a heat-adhesive resin such as polypropylene, acid-modified polypropylene, low-density polyethylene, or linear low-density polyethylene. Multiple layers of resins of different materials may be laminated to form the heat-adhesive resin layer 43. The thickness of the heat-adhesive resin layer 43 is formed to be, for example, 10 μm or more and 100 μm or less. The heat-adhesive resin layer 43 is formed by extrusion onto the barrier layer 42. The film forming the heat-adhesive resin layer 43 may be bonded to the barrier layer 42 via an adhesive. Depending on the size of the energy storage element 20 housed in the housing 11, and the weight of the energy storage element 20 and the electrolyte, the thickness of the heat-adhesive resin layer 43 may be 100 μm or more and 500 μm or less.
[0022] In the resin sheet 40 of this embodiment, the heat-adhesive resin layer 43 is formed by sequentially extruding acid-modified polypropylene (thickness 40 μm) and polypropylene (thickness 40 μm) onto the barrier layer 42. In the second sealing portion 122 of the sealing band portion 12, the heat-adhesive resin layer 43 of the first packaging material 141 and the heat-adhesive resin layer 43 of the second packaging material 142 are brought into contact with each other and bonded by heat sealing through heating and pressurization.
[0023] Figure 5 is an exploded perspective view of the energy storage device 1. The exterior member 10 is formed integrally from a first packaging material 141 and a second packaging material 142 in a continuous manner in the Y direction. The first packaging material 141 has a housing portion 11 and a flange portion 15. The first packaging material 141 and the second packaging material 142 are made of resin sheets. The first packaging material 141 is formed, for example, by cold forming to create a housing portion 11 recessed to a predetermined depth relative to the flange portion 15. The housing portion 11 has a substantially rectangular opening 11a on one side to house the energy storage element 20. The flange portion 15 is formed to protrude outward from one of the short and long sides of the opening 11a. The second packaging material 142 is formed in the shape of a rectangular sheet. A sealing band portion 12 is formed by, for example, heat bonding the second packaging material 142 to the flange portion 15. The second packaging material 142 also forms a lid portion 16 that covers the opening 11a.
[0024] <Sealing band 12> Next, the details of the sealing band 12 will be described. The sealing band 12 has two first sealing parts 121, a second sealing part 122, and a fastening part 123. In a front view, the sealing band 12 is strip-shaped and configured to connect to one of the long sides and both of the short sides of the housing part 11. In the sealing band 12, the first packaging material 141 and the second packaging material 142 are in close contact. Here, close contact means that gases released from the electrolyte sealed in the housing part 11, and gases generated by rapid charging, etc., do not leak to the outside, and that contact is made while blocking water vapor from the outside.
[0025] In the sealing band portion 12, the first sealing portion 121 is the portion that overlaps with the positive terminal 31 or the negative terminal 32 in the front and back. The second sealing portion 122 is the portion of the sealing band portion 12 other than the first sealing portion 121.
[0026] In other words, in a front view, the portion of the sealing band 12 that connects to both short sides of the housing 11 and overlaps with the positive terminal 31 or negative terminal 32 in the front and back is the first sealing portion 121. The entire portion of the sealing band 12 that connects to one of the long sides of the housing 11, and the portion of the short side other than the first sealing portion 121, constitutes the second sealing portion 122.
[0027] In the first sealing portion 121, the positive terminal 31 and negative terminal 32 of the terminal portion 30 are sandwiched between the flange portion 15 and the lid portion 16 via a heat-adhesive tab film 50. In this state, the flange portion 15 and the lid portion 16 are heated and pressurized. As a result, the first packaging material 141 and the second packaging material 142 are indirectly melted and bonded together. This improves the sealing performance around the first sealing portion 121.
[0028] As a result, in the first sealing portion 121, the first packaging material 141 and the second packaging material 142 are in close contact with the positive terminal 31 and the negative terminal 32 of the terminal portion 30.
[0029] Furthermore, in the second sealing section 122, the heat-adhesive resin layers 43 of the first packaging material 141 and the second packaging material 142 are in direct contact. In this state, the first packaging material 141 and the second packaging material 142 are heat-bonded by heating and pressurizing them. In other words, in the second sealing section 122, the first packaging material 141 and the second packaging material 142 are directly melted and bonded together.
[0030] Furthermore, in the sealing band portion 12, the fastening portion 123 is formed along the entire length of the second sealing portion 122. The fastening portion 123 is formed by sewing the first packaging material 141 and the second packaging material 142 together with a wire 124 having a higher heat resistance temperature than the resin sheet 40. The wire 124 is an example of a fastening member. Examples of the wire 124 include fine stainless steel wire, fine tungsten wire, and fine aramid fiber wire. However, it is not limited to these, and a wide range of wires with a higher heat resistance temperature than the resin sheet 40, or flame-retardant wires, can be used as the wire 124. As shown in Figure 1, the fastening portion 123 sews the first packaging material 141 and the second packaging material 142 together, including the tab film 50, but it is not limited to this. For example, the tab film 50 may not be fastened by the fastening portion 123.
[0031] When the energy storage device 1 is repeatedly charged and discharged, particularly through rapid charging, the electrolyte contained in the storage section 11 becomes hot, accelerating its decomposition and generating gas. The generation of gas increases the pressure inside the storage section 11, and a force acts on the sealing band 12 that separates the first packaging material 141 from the second packaging material 142. The force separating the first packaging material 141 from the second packaging material 142 is a force corresponding to the amount and speed of gas generation, or the force of expansion and contraction due to the charging and discharging of the battery itself. Due to the shape characteristics of the sealing band 12, the force separating the first packaging material 141 from the second packaging material 142 tends to concentrate in the center of the X-direction of the portion adjacent to the long side of the storage section 11. Because the fastening portion 123 is formed along the entire length of the second sealing portion 122, the fastening force of the fastening portion 123 counteracts the force that would cause the first packaging material 141 and the second packaging material 142 to separate in the second sealing portion 122, making separation less likely to occur.
[0032] Furthermore, as shown in Figures 1, 2, and 3, the width of the sealing band portion 12 from the inside to the outside of the first sealing portion 121 is defined as width W1, and the width of the sealing portion 122 from the inside to the outside is defined as width W2. In this case, width W1 is greater than width W2. That is, the width W1 of the first sealing portion 121 is wider than the width W2 of the second sealing portion 122. As a result, the fastening strength of the first sealing portion 121 is higher than that of the second sealing portion 122. Therefore, even if a force that causes the first packaging material 141 and the second packaging material 142 to separate is applied to the first sealing portion 121, delamination is less likely to occur at the first sealing portion 121. Note that even if the width W1 is narrow and the fastening strength is weak, an auxiliary mechanism can be provided on the outside.
[0033] As described above, in the exterior member 10 of the energy storage device 1, the first sealing portion 121 increases the width W1 to expand the area that is heat-bonded, thereby increasing the fastening strength and suppressing delamination between the first packaging material 141 and the second packaging material 142. In addition, the second sealing portion 122 has a fastening portion 123 formed along its entire length, and the fastening force of the fastening portion 123 counteracts the force that would cause the first packaging material 141 and the second packaging material 142 to separate, thereby suppressing delamination between the first packaging material 141 and the second packaging material 142.
[0034] As described above, the force that separates the first packaging material 141 and the second packaging material 142 is concentrated in the center of the X-direction of the portion of the second sealing portion 122 that connects to the long side of the housing portion 11. However, it may also be concentrated in other locations. In this way, the spacing (pitch) of the stitches when sewing with the wire 124 of the fastening portion 123 may be made narrower in the portion where the force that separates the first packaging material 141 and the second packaging material 142 is concentrated. In addition, multiple stages of the fastening portion 123 may be provided in the portion where the force that separates the first packaging material 141 and the second packaging material 142 is concentrated.
[0035] With this configuration, the sealing performance can be maintained even if the internal pressure increases due to repeated rapid charging of the energy storage device 1, or if it expands and contracts due to discharge, and even if thermal runaway occurs in the event of an abnormality such as an internal short circuit or nail penetration.
[0036] As described above, the exterior member 10 of the energy storage device 1 is a so-called single-cup type container in which a housing portion 11 is formed in a recess in the first packaging material 141, but it is not limited to this. For example, the exterior member 10 may be a double-cup type container in which recesses are formed in both the first packaging material 141 and the second packaging material 142 and the openings are joined together. Alternatively, it may be a four-sided seal type container in which a lid portion 16 made of the second packaging material 142 seals the flange portion 15 that extends outward from the four sides of the opening 11a of the housing portion 11. Furthermore, the first packaging material 141 and the second packaging material 142 may each be formed from separate sheets.
[0037] Furthermore, in the energy storage device 1 of this embodiment, one of the long sides of the rectangular shape in a plan view is the folded portion between the first packaging material 141 and the second packaging material 142, with the positive terminal 31 located on one short side and the negative terminal 32 located on the other short side. However, the configuration is not limited to this, and for example, a configuration in which the positive terminal 31 and the negative terminal 32 are located on one short side may also be used.
[0038] Furthermore, at least one of the positive terminal 31 and the negative terminal 32 may be located on the long side opposite to the folded portion of the first packaging material 141 and the second packaging material 142, or both may be located there.
[0039] Furthermore, if the energy storage device 1A is of the four-sided seal type, the positive terminal 31 may be located in the sealing band 12 provided on the short side or on the sealing band 12 provided on the long side. Similarly, the negative terminal 32 may be located in the sealing band 12 provided on the short side or on the sealing band 12 provided on the long side.
[0040] <Energy storage module 100> The details of the energy storage module 100 will be described below with reference to the drawings. Figure 6 is a perspective view of the energy storage module 100. The energy storage module 100 consists of multiple energy storage devices 1 housed in a case 200. Note that in the energy storage module 100 shown in Figure 6, a portion of the body 201 has been omitted from the illustration for ease of understanding.
[0041] As shown in Figure 6, in the energy storage module 100, 10 energy storage devices 1 are arranged inside the case 200. However, the actual number of devices arranged is not limited to 10, and the number of energy storage devices 1 arranged in the energy storage module 100 and the connection method may be changed depending on the required electrical capacity, output voltage, etc. When the energy storage devices 1 are connected in parallel, they are arranged so that the positive terminals 31 and negative terminals 32 of adjacent energy storage devices 1 are adjacent to each other. Also, when the energy storage devices are connected in series, they are arranged in the case 200 so that the positive terminals 31 and negative terminals 32 of adjacent energy storage devices 1 are adjacent to each other.
[0042] The case 200 has a body portion 201 and a closing portion 202. The body portion 201 is formed in a cylindrical shape with both axial ends open. The closing portion 202 closes both axial ends of the body portion 201. By attaching the closing portion 202 to the body portion 201, the case 200 is sealed to prevent moisture from entering from the outside.
[0043] The case 200 is formed from an insulator such as resin. In some cases, metals such as aluminum alloy or stainless steel may be used to increase the strength of the case 200. In this case, the inner surface that comes into contact with the energy storage device 1 and the parts that may come into contact with the electrode terminals are insulated.
[0044] Furthermore, the positive terminal 31 and negative terminal 32 of each energy storage device 1 are connected to a busbar (not shown). Lead terminals (not shown) are connected to the busbar, and these lead terminals are brought out to the outside of the case 200. The lead terminals are external connection terminals that are connected to external equipment such as charging devices and loads.
[0045] The case 200 may also be equipped with an auxiliary mechanism (not shown) to increase the fastening strength of the first sealing portion 121, or a retaining member (not shown) to suppress the movement of the energy storage device 1 inside the case 200.
[0046] <Electric Vehicle 300> Figure 7 is a side view of the electric vehicle 300. Figure 8 is a top view of the electric vehicle 300. The electric vehicle 300 is equipped with a drive motor 302 as a power source to drive the wheels 301. A power storage pack 400 is installed under the floor of the vehicle body (mobile body) of the electric vehicle 300 as a power source to supply power to the drive motor 302.
[0047] The energy storage pack 400 has a configuration in which multiple energy storage modules 100 are arranged in a row on an exterior component such as a frame (not shown). By connecting the energy storage modules 100 arranged on the exterior component such as the frame in series and in parallel, the energy storage pack 400 can obtain the required energy storage capacity and output the required output voltage.
[0048] As shown in Figure 8, in the energy storage pack 400, the energy storage modules 100 are arranged such that the Y direction is the height direction (gravity direction) of the electric vehicle 300, the Z direction is the front-to-back direction of the electric vehicle 300, and the X direction is the left-to-right direction of the electric vehicle 300. In other words, in the energy storage pack 400, energy storage modules 100 with the Y direction as the height direction are arranged in the X and Z directions.
[0049] Furthermore, if the electric vehicle 300 is a low-profile sedan or compact car type, the energy storage pack 400 will use a single-stage configuration of energy storage modules 100 in the height direction. If the electric vehicle 300 is a high-profile SUV or minivan type, the energy storage modules 100 will be used in a multi-stage configuration in the height direction of the vehicle. In this way, it is possible to provide an energy storage pack 400 with output voltage and storage capacity appropriate to the weight and size of the vehicle.
[0050] Alternatively, the electric vehicle 300 may be positioned such that the X-direction, which intersects the Z-direction in which the energy storage devices 1 in the energy storage module 100 are arranged, is the direction of travel. In this way, even when the energy storage module 100 is positioned on the electric vehicle 300, the same effects as described above can be obtained.
[0051] Alternatively, the energy storage devices 1 may be directly arranged on the underside (chassis) of the electric vehicle 300 to form an energy storage unit with the same output voltage and storage capacity as the energy storage pack 400. By doing so, the exterior components such as the frame of the energy storage pack 400 can be omitted, thus enabling weight reduction. When the underside (chassis) of the electric vehicle 300 is configured in this way, the case 200 can also be omitted, further enabling weight reduction.
[0052] In addition to BEVs (Battery Electric Vehicles) and PHEVs (Plug-in Hybrid Electric Vehicles), other examples of mobile vehicles that can be equipped with the aforementioned 400 energy storage pack include HEVs (Hybrid Electric Vehicles) and micro-hybrid vehicles with a 48V power supply.
[0053] Furthermore, the aforementioned energy storage module or energy storage pack may be mounted on other mobile devices. Examples of mobile devices that can be equipped with the energy storage module or energy storage pack include bipedal robots, trains, airplanes, helicopters, drones, flying cars, agricultural machinery, construction machinery, etc. Note that if the required output voltage and energy storage capacity are sufficient, the energy storage module may be used as a standalone unit.
[0054] Furthermore, the energy storage module or energy storage pack may be used for purposes other than as a power source for mobile devices. For example, it may be used as a fixed power source for an Energy Storage System, a Battery Energy Storage System, or an Uninterruptible Power Supply.
[0055] <First variation> The first modified example of the energy storage device 1A will be described with reference to the drawings. Figure 9 is a front view of the first modified example of the energy storage device 1A. In the energy storage device 1A shown in Figure 9, the shape of the outer casing member 10A, the energy storage element 20A, and the positive terminal 31A and negative terminal 32A of the terminal section 30A differ from those of the outer casing member 10, the energy storage element 20, and the positive terminal 31 and negative terminal 32 of the terminal section 30. Other than these differences, the energy storage device 1A has the same configuration as the energy storage device 1. Therefore, parts of the energy storage device 1A that are substantially the same as those of the energy storage device 1 are given the same reference numerals, and detailed descriptions of these same parts are omitted.
[0056] As shown in Figure 9, in a front view, the housing portion 11 of the exterior member 10A of the energy storage device 1A is rectangular in shape with the Y direction as the longitudinal direction. Two first sealing portions 121 are formed at both ends in the X direction of the portion of the sealing band 12A that connects to one end of the housing portion 11 in the Y direction. A positive terminal 31A is placed on one of the two first sealing portions 121A, and a negative terminal 32A is placed on the other. The portion of the sealing band 12A other than the first sealing portions 121A is the second sealing portion 122A.
[0057] In the energy storage device 1A, the width of the first sealing portion 121A extending from the housing portion 11 to the outside is greater than the width of the other parts of the sealing band portion 12. Therefore, the adhesive strength between the positive terminal 31A or the negative terminal 32A and the first packaging material 141 and the second packaging material 142 is increased in the first sealing portion 121A. In addition, a fastening portion 123 is formed along the entire length of the second sealing portion 122A of the sealing band portion 12A of the energy storage device 1A.
[0058] As a result, even if the storage device 1A is repeatedly charged and discharged and the pressure inside the storage section 11 increases, the sealing performance of the storage section 11 can be maintained.
[0059] <Second variation> Further examples of energy storage devices will be described with reference to the drawings. Figure 10 is an enlarged front view of the second modified example of energy storage device 1B. Figure 11 is a cross-sectional view of the energy storage device 1B shown in Figure 10, taken along the line XI-XI. Figure 10 shows an enlarged view of the vicinity where the positive terminal 31B of the terminal portion 30B of the energy storage device 1B is located. In the energy storage device 1B, the shape of the positive terminal 31B of the outer casing member 10B differs from that of the positive terminal 31, and the configuration of the fastening portion 125 of the sealing band portion 12B differs from that of the fastening portion 123 of the sealing band portion 12. In all other respects, the energy storage device 1B has the same configuration as the energy storage device 1. The same reference numerals are used for the same parts of the energy storage device 1B as in the energy storage device 1, and detailed descriptions of the same parts are omitted. The negative terminal, which is not shown, has a similar configuration.
[0060] As shown in Figures 10 and 11, in the energy storage device 1B, the positive electrode terminal 31B has multiple through holes 311 that penetrate the first packaging material 141, the tab film 50, the positive electrode terminal 31B, and the second packaging material 142 in the Z direction. The through holes 311 are arranged in the Y direction. In the first sealing portion 121B of the energy storage device 1B, the wire 124 of the fastening portion 125 penetrates the first packaging material 141, the through holes 311, and the second packaging material 142. To explain further, the wire 124 is inserted through the through holes 311, and in the first sealing portion 121B, the first packaging material 141 and the second packaging material 142 are sewn to the positive electrode terminal 31B to form the fastening portion 125.
[0061] This configuration suppresses the peeling of the first packaging material 141 and the second packaging material 142 in the first sealing portion 121. In the energy storage device 1B, the fastening portion 125 is formed along the entire length of the sealing band portion 12B. This configuration allows the entire fastening portion 125 to be formed from a single wire, making it difficult to form weaker parts than other parts of the fastening portion 125. This increases the fastening force provided by the fastening portion 125. The fastening portion 125 may also be partially discontinuous. For example, the fastening portion 125 may be formed by dividing it into portions located at both ends in the X direction of the sealing band portion 12B and a portion located at one end in the Y direction.
[0062] As shown in Figure 12, the portion where the fastening portion 125 of the positive terminal 31B is formed may be the mesh portion 312. With this configuration, the fastening portion 125 can be formed on the first sealing portion 121B using a sewing machine or the like. This makes it easy to form the fastening portion 125 on the first sealing portion 121B. The ratio of the opening area of the mesh portion 312 is preferably such that the positive terminal 31B has a certain level of rigidity while being easy to sew with the wire 124. The negative terminal may have a similar configuration.
[0063] <Third variation> Further examples of energy storage devices will be described with reference to the drawings. Figure 13 is an enlarged cross-sectional view of the fastening portion 126 of the third modified energy storage device 1C. The configuration of the fastening portion 126 in energy storage device 1C differs from that of the fastening portion 123 of energy storage device 1. In all other respects, energy storage device 1C has the same configuration as energy storage device 1. The same reference numerals are used for the same parts of energy storage device 1C as in energy storage device 1, and detailed descriptions of the same parts are omitted.
[0064] As shown in Figure 13, the fastening portion 126 of the energy storage device 1C uses staples 127. The first packaging material 141 and the second packaging material 142 are fastened together along the entire length of the second sealing portion 122. Note that the staples 127 are just one example of fastening members. By constructing the fastening portion 126 using staples 127 in this way, it is easier to manufacture compared to a fastening portion constructed by sewing together wires. The material of the staples 127 can be metal or a material equivalent to that of the wire 124.
[0065] It should be noted that the present invention is not limited to the configuration described above, and various modifications are possible. Configurations obtained by appropriately combining the technical means disclosed for each different configuration are also included within the technical scope of the present invention.
[0066] <Summary> The energy storage module of the present invention has the following configuration.
[0067] (1) An electrode section in which positive electrode plates and negative electrode plates are alternately stacked with an intermediate member in between, An outer packaging member having a first packaging material and a second packaging material that cover the electrode portion from both outer sides in the stacking direction of the electrode portion, It has terminal portions that are electrically connected to the positive electrode plate and the negative electrode plate, The exterior member is, A housing portion for housing the electrode portion, It has a sealing band portion that is connected to at least a part of the outer edge of the housing portion so that the first packaging material and the second packaging material are directly or indirectly bonded together, The sealing band portion has a fastening portion that applies a fastening force in the stacking direction to the first packaging material and the second packaging material by a fastening member that penetrates and fastens the first packaging material and the second packaging material.
[0068] (2) The sealing band portion is A first sealing portion to which the first packaging material and the second packaging material are adhered to the electrode portion, It has a second sealing portion which is a different portion from the first sealing portion and to which the first packaging material and the second packaging material are directly bonded, The fastening portion is such that at least the second sealing portion is formed continuously along its entire length, as described in (1) for the energy storage device.
[0069] (3) The sealing band portion is A first sealing portion to which the first packaging material and the second packaging material are adhered to the electrode portion, It has a second sealing portion which is a different portion from the first sealing portion and to which the first packaging material and the second packaging material are directly bonded, The fastening portion is formed in the first sealing portion, The fastening member of the fastening portion formed in the first sealing portion which is bonded to at least the electrode portion of the positive electrode is conductive, as described in (1) or (2).
[0070] (4) The portion of the terminal to which the first sealing portion is bonded has a plurality of through holes that penetrate in the stacking direction, The energy storage device according to (2) or (3), wherein the fastening portion is formed by the fastening member passing through the through hole.
[0071] (5) The energy storage device according to any one of (1) to (4), wherein the width of the first sealing portion extending outward from the housing portion is wider than the width of the second sealing portion extending outward from the housing portion.
[0072] (6) The fastening portion is formed continuously along the entire length of the sealing band portion in a direction along the outer edge of the housing portion, as described in any of (1) to (5).
[0073] (7) The fastening portion is made of wire with a higher heat resistance temperature than the exterior member. The energy storage device according to any one of (1) to (6).
[0074] (8) The fastening member is a staple, the energy storage device according to any one of (1) to (7).
[0075] (9) A plurality of energy storage devices as described in any of (1) to (8), A storage module having a case capable of housing the aforementioned storage devices in the stacking direction.
[0076] (10) Multiple energy storage modules as described in (9), A drive motor powered by the aforementioned energy storage module, A mobile body having the aforementioned energy storage module and the aforementioned drive motor arranged in a main body, and being driven by the aforementioned drive motor. [Industrial applicability]
[0077] According to the present invention, it can be widely used in mobile bodies equipped with electric devices. [Explanation of Symbols]
[0078] 100 Energy Storage Modules 200 cases 201 Torso 202 Occlusion 300 electric vehicles 301 wheels 302 Drive motor 311 Through hole 312 Mesh section 400 Battery Storage Pack 1, 1A, 1B, 1C Energy Storage Devices 10, 10A, 10B Exterior components 11, 11a opening 12, 12A, 12B Sealing band 121, 121A, 121B 1st sealing part 122, 122A 2nd sealing part 123 Fastening part 124 Wire rod 125 Fastening part 126 Fastening part 127 staples 141 1st packaging material 142 Second packaging material 15 Flange section 16 Lid 20, 20A energy storage element 21 Positive plate 22 Negative plate 23 Separator 30, 30A, 30B terminal section 31, 31A, 31B Positive terminal 32, 32A negative terminal 40 resin sheets 41 Base material layer 42 Barrier layer 43 Heat adhesive resin layer 50 Tab Films
Claims
1. An electrode section in which positive and negative plates are alternately stacked with an intermediate member in between, An outer packaging member having a first packaging material and a second packaging material that cover the electrode portion from both outer sides in the stacking direction of the electrode portion, It has terminal portions that are electrically connected to the positive electrode plate and the negative electrode plate, The exterior member is, A housing portion for housing the electrode portion, It has a sealing band portion that is connected to at least a part of the outer edge of the housing portion so that the first packaging material and the second packaging material are directly or indirectly bonded together, The sealing band portion has a fastening portion that applies a fastening force in the stacking direction to the first packaging material and the second packaging material by a fastening member that penetrates and fastens the first packaging material and the second packaging material, respectively, in the energy storage device.
2. The sealing band portion is A first sealing portion to which the first packaging material and the second packaging material are adhered to the electrode portion, It has a second sealing portion which is a different portion from the first sealing portion and to which the first packaging material and the second packaging material are directly bonded, The fastening portion is such that at least the second sealing portion is formed continuously along its entire length, as described in claim 1 of the energy storage device.
3. The energy storage device according to claim 2, wherein the width of the first sealing portion extending outward from the housing portion is wider than the width of the second sealing portion extending outward from the housing portion.
4. The energy storage device according to claim 1, wherein the fastening portion is formed continuously along the entire length in a direction along the outer edge of the housing portion of the sealing band portion.
5. The portion of the terminal to which the first sealing portion is bonded has a plurality of through holes that penetrate in the stacking direction, The energy storage device according to claim 2, wherein the fastening portion is formed by the fastening member passing through the through hole.
6. The sealing band portion is A first sealing portion to which the first packaging material and the second packaging material are adhered to the electrode portion, It has a second sealing portion which is a different portion from the first sealing portion and to which the first packaging material and the second packaging material are directly bonded, The fastening portion is formed in the first sealing portion, The energy storage device according to claim 1, wherein the fastening member of the fastening portion formed in the first sealing portion which is bonded to the electrode portion of the positive electrode is conductive.
7. The energy storage device according to claim 1, wherein the fastening portion is made of a wire with a higher heat resistance temperature than the exterior member.
8. The energy storage device according to claim 1, wherein the fastening member is a staple.
9. A plurality of energy storage devices according to any one of claims 1 to 8, A storage module having a case capable of housing the aforementioned storage devices in the stacking direction.
10. The energy storage module according to claim 9, A drive motor powered by the aforementioned energy storage module, A mobile body having the aforementioned energy storage module and the aforementioned drive motor arranged in a main body, and being driven by the aforementioned drive motor.