Battery control system, battery control method, and battery control device

Abstract

This improves the reliability of batteries, including those with laminated film casings. [Solution] The battery control system 100 comprises a battery 10, a first temperature sensor 20, and a control device 30. The battery 10 includes a power generation element 18, a tab lead 14 comprising a resin part 13 and a metal part 12, and an outer casing material 15 including a laminate film. The outer periphery of the outer casing material 15 includes a welded portion 16. The first temperature sensor 20 detects the temperature of the welded portion 16, and the control device 30 controls the charging and discharging of the battery 10 based on the temperature of the welded portion 16 detected by the first temperature sensor 20.

Description

[Technical Field]

[0001] This disclosure relates to a battery control system, a battery control method, and a battery control device. [Background technology]

[0002] Patent Document 1 discloses a system for preventing damage to terminals due to heat generation in a battery pack in which different terminals are used between the battery pack and the device connected to the battery pack.

[0003] Patent Document 2 discloses a non-aqueous electrolyte secondary battery and battery control system that can be miniaturized, have high load characteristics, a long lifespan, and are safer. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2021-89824 [Patent Document 2] Japanese Patent Publication No. 2007-335352 [Overview of the project] [Problems that the invention aims to solve]

[0005] Conventional technologies require improved reliability of batteries, including those with laminated film casings. [Means for solving the problem]

[0006] This disclosure is, Batteries and First temperature sensor and, Control device and Equipped with, The aforementioned battery includes a power generation element, a tab lead comprising a resin part and a metal part, and an outer casing material including a laminate film. The outer periphery of the exterior material includes a welded portion, The first temperature sensor detects the temperature of the welded portion, The control device controls the charging and discharging of the battery based on the temperature of the welded portion detected by the first temperature sensor. We provide a battery control system. [Effects of the Invention]

[0007] The control system disclosed herein can improve the reliability of batteries, including those with laminated film casings. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a diagram showing the configuration of the battery control system in an embodiment. [Figure 2] Figure 2 is a plan view of the power generation element and tab lead. [Figure 3] Figure 3 is a flowchart of the control performed by the control device. [Figure 4] Figure 4 is a diagram showing the configuration of the battery control system in Modification Example 1. [Figure 5] Figure 5 is a diagram showing the configuration of the battery control system in modified example 2. [Figure 6] Figure 6 is a diagram showing the configuration of the battery control system in modified example 3. [Figure 7] Figure 7 is a flowchart of the control performed by the control device. [Figure 8] Figure 8 is a diagram showing the configuration of the battery control system in modified example 4. [Figure 9] Figure 9 is a graph showing the relationship between the temperature of the welded area and time. [Modes for carrying out the invention]

[0009] (Knowledge that forms the basis of this disclosure) A laminate film used for a battery generally includes three layers: an inner resin layer, a metal layer, and an outer resin layer. By heat-welding the inner resin layers to each other, or by heat-welding the resin portion of a tab lead and the inner resin layer of the laminate film, the interior of the battery is sealed, and the entry of outside air into the interior of the battery is prevented. Since the welded portion is formed of resin, when the battery is exposed to a high temperature exceeding the melting point or softening point of the resin, the adhesive strength of the welded portion may decrease, which may reduce the reliability of the battery. For example, when polypropylene is used for the inner resin layer, its softening point is approximately 110° C. When the battery is exposed to a high temperature exceeding approximately 110° C., the adhesive strength of the welded portion may decrease. Particularly in the case of a battery that can operate stably at a temperature higher than the melting point or softening point of the resin, the temperature of the welded portion is an important indicator that determines the reliability of the battery.

[0010] Patent Document 1 describes detecting the temperature in the vicinity of a terminal. However, it does not disclose detecting the temperature of the welded portion.

[0011] Patent Document 2 discloses disposing a temperature sensor together with a sealing resin on an electrode-side lead having a high resistance value. However, it does not disclose controlling charging and discharging of the battery based on the temperature detected by the temperature sensor.

[0012] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0013] (Embodiment) FIG. 1 is a configuration diagram of a battery control system according to the embodiment. FIG. 2 is a plan view of a power generation element and a tab lead. A battery control system 100 (hereinafter simply referred to as "control system 100") includes a battery 10, a first temperature sensor 20, and a control device 30.

[0014] The battery 10 includes a power generation element 18, tab leads 14, and an outer casing 15. The power generation element 18 includes a positive electrode, an electrolyte layer, and a negative electrode. The tab leads 14 include a metal part 12 and a resin part 13. The outer casing 15 is a component that serves as the container for the battery 10 and is made of laminate film. The outer periphery of the outer casing 15 includes a welded portion 16. The battery 10 is typically a rechargeable battery.

[0015] The laminate film includes an internal resin layer, a metal layer, and an external resin layer. These layers are laminated in this order. The internal and external resin layers are made of thermoplastic resins such as polypropylene and polyethylene terephthalate. The metal layer is made of a metallic material such as aluminum.

[0016] The first temperature sensor 20 detects the temperature of the welded portion 16. In this embodiment, the first temperature sensor 20 is provided on the surface of the exterior material 15 outside the battery 10. The first temperature sensor 20 is a thermocouple or a thermistor. The temperature detection result from the first temperature sensor 20 is input to the control device 30. The first temperature sensor 20 may also be placed inside the welded portion 16, that is, between the internal resin layer of the laminate film and the resin portion 13 of the tab lead 14.

[0017] The control device 30 controls the charging and discharging of the battery 10 based on the temperature of the welded portion 16 detected by the first temperature sensor 20. The control device 30 is, for example, a microcomputer.

[0018] The control system 100 may further include a power supply circuit 32. The control device 30 controls the charging and discharging of the battery 10 via the power supply circuit 32. The power supply circuit 32 is connected to a load or an external power supply (not shown). Note that the control device 30 may include the power supply circuit 32.

[0019] As current flows during charging and discharging, the temperature of the battery 10 rises due to self-heating caused by internal resistance. The temperature of the welded portion 16 is detected by the first temperature sensor 20, and the control device 30 appropriately controls the charging and discharging of the battery 10 based on the detected temperature. Since the temperature of the welded portion 16 is an important indicator for determining the reliability of the battery 10, this embodiment can improve the reliability of the battery 10.

[0020] The welded portion 16 includes a tab welded portion 17. The tab welded portion 17 is the connection between the resin portion 13 of the tab lead 14 and the laminate film. The first temperature sensor 20 detects the temperature of the tab welded portion 17. The tab lead 14 is connected to the power generation element 18 at the connection portion 19. The connection portion 19 is, for example, the welded portion between the tab lead 14 and the power generation element 18.

[0021] When the temperature of the battery 10 rises due to self-heating, the temperature of the tab welding portion 17 located near the tab lead 14 through which the current flows is likely to be the highest within the welding portion 16. Therefore, by detecting the temperature near the tab welding portion 17, it is possible to obtain information about the area of ​​the welding portion 16 that is most likely to have reduced reliability. By appropriately controlling the charging and discharging of the battery 10 based on the temperature near the tab welding portion 17, the reliability of the battery 10 can be further improved.

[0022] In the control system 100, a threshold temperature T1 is set in advance based on the heat resistance temperature of the welded portion 16. When the temperature of the welded portion 16 reaches the threshold temperature T1, the control device 30 reduces the charging current value of the battery 10, reduces the discharge current value of the battery 10, or stops charging and discharging the battery 10.

[0023] By reducing the current value or stopping charging and discharging, self-heating due to internal resistance can be suppressed. With such control, the temperature of the welded portion 16 can be prevented from rising excessively, and the reliability of the battery 10 can be further improved.

[0024] The threshold temperature T1 can be set arbitrarily. The threshold temperature T1 may be set based on the melting point of the internal resin layer of the laminate film, the softening point of the internal resin layer of the laminate film, the temperature at which the adhesive strength of the welded portion 16 decreases, or the temperature at which the welded portion 16 melts and its airtightness is compromised. Even after the current value decreases or charging / discharging stops, the temperature of the welded portion 16 may continue to rise due to heat conduction. Therefore, the threshold temperature T1 may be set to a temperature sufficiently lower than each of the above temperatures, taking into account the temperature rise after charging / discharging control. By appropriately setting the threshold temperature T1, it is possible to suppress the temperature of the welded portion 16 from rising excessively, and the reliability of the battery 10 can be further improved. In one example, the threshold temperature T1 is a temperature in the range of 50°C to 250°C.

[0025] Figure 3 is a flowchart of the control performed by the control device 30. The control device 30 periodically performs each of the processes shown in the flowchart of Figure 3. The temperature of the welded portion 16 is monitored by the control device 30.

[0026] In step S1, the temperature of the welded portion 16 is detected. The temperature of the welded portion 16 is detected by the first temperature sensor 20. The detection signal from the first temperature sensor 20 is input to the control device 30.

[0027] In step S2, it is determined whether the temperature of the welded portion 16 is equal to or greater than the threshold temperature T1. If the temperature of the welded portion 16 is equal to or greater than the threshold temperature T1, in step S3, charging or discharging of the battery 10 is stopped. Instead of stopping charging or discharging, the charging current value of the battery 10 may be reduced, or the discharging current value of the battery 10 may be reduced.

[0028] After charging or discharging stops, in step S4, the system waits for a predetermined time. The "predetermined time" is the time it is expected that the temperature of the welded portion 16 will have decreased sufficiently. In one example, the "predetermined time" is in the range of 1 second to 3600 seconds.

[0029] After a predetermined time has elapsed, in step S5, the temperature of the welded portion 16 is detected again.

[0030] In step S6, it is determined whether the temperature of the welded portion 16 is below the threshold temperature T1. If the temperature of the welded portion 16 is lower than the threshold temperature T1, charging or discharging is resumed in step S7. Instead of resuming charging or discharging, the charging current value of the battery 10 may be increased, or the discharging current value of the battery 10 may be increased.

[0031] After the temperature of the welded portion 16 reaches a temperature at which the battery 10 can operate safely, the charging current value can be increased, the discharging current value can be increased, or charging or discharging can be restarted, thereby efficiently controlling the charging and discharging of the battery 10 while ensuring the reliability of the battery 10.

[0032] In this embodiment, the power generation element 18 of the battery 10 may include a solid electrolyte.

[0033] Unlike non-aqueous electrolytes, which consist of organic electrolytes that decompose at high temperatures, solid electrolytes generally exhibit stable properties even at high temperatures. Therefore, when the power generation element 18 contains a solid electrolyte, the heat resistance of the power generation element 18 is increased. When the power generation element 18 operates stably at a temperature higher than the melting or softening point of the internal resin layer of the laminate film, the temperature of the welded portion 16 becomes a more important indicator for determining the reliability of the battery 10. Accordingly, by applying the technology of this disclosure to a battery 10 in which the power generation element 18 contains a solid electrolyte, the reliability of the battery 10 can be more effectively improved.

[0034] A solid electrolyte is a material that has ionic conductivity. The solid electrolyte may be a lithium ion conductor, a sodium ion conductor, or a magnesium ion conductor. Examples of solid electrolytes include sulfide solid electrolytes, halide solid electrolytes, oxide solid electrolytes, polymer solid electrolytes, and complex hydride solid electrolytes.

[0035] Examples of sulfide solid electrolytes include Li2S-P2S5, Li2S-SiS2, Li2S-B2S3, Li2S-GeS2, and Li 3.25 Ge 0.25 P 0.75 S4, Li10 GeP₂S 12 Examples include the above. Sulfide solid electrolytes having an argyrodite structure represented by Li₆PS₅Cl, Li₆PS₅Br, Li₆PS₅I and the like may be used. These solid electrolytes may be added with LiX, Li₂O, MO q , Li p MO q and the like. X is at least one selected from the group consisting of F, Cl, Br and I. M is at least one selected from the group consisting of P, Si, Ge, B, Al, Ga, In, Fe and Zn. p and q are each independently a natural number.

[0036] Examples of halide solid electrolytes include Li₃YX₆, Li₂MgX₄, Li₂FeX₄, Li(Al, Ga, In)X₄, Li₃(Al, Ga, In)X₆ and the like.

[0037] The halide solid electrolyte may contain Li, M2, O and X. M2 is at least one selected from the group consisting of Ta and Nb. X is at least one selected from the group consisting of Cl, Br and I. In order to further improve lithium ion conductivity, the halide solid electrolyte may substantially consist of Li, M2, O and X. Here, "substantially consisting of Li, M2, O and X" means that the molar ratio of the total amount of substances of Li, M2, O and X to the total amount of substances of all elements in the halide solid electrolyte is 90% or more. As an example, the molar ratio may be 95% or more.

[0038] Examples of oxide solid electrolytes include: NASICON-type solid electrolytes represented by LiTi₂(PO₄)₃ and element-substituted products thereof; (LaLi)TiO₃-based perovskite-type solid electrolytes; Li 14 ZnGe₄O 16 , LISICON-type solid electrolytes represented by Li₄SiO₄, LiGeO₄ and element-substituted products thereof; Li₇La₃Zr₂O 12Examples include garnet-type solid electrolytes, such as those with elemental substitutions; Li3PO4 and its N-substituted counterparts; and glass or glass ceramics, which are based on Li-BO compounds such as LiBO2 and Li3BO3 to which Li2SO4, Li2CO3, etc., are added.

[0039] Polymeric solid electrolytes can be compounds of polymer compounds and lithium salts. The polymer compound may have an ethylene oxide structure. Polymer compounds having an ethylene oxide structure can contain a large amount of lithium salt and thus achieve high ionic conductivity. Examples of lithium salts include LiPF6, LiBF4, LiSbF6, LiAsF6, LiSO3CF3, LiN(SO2CF3)2, LiN(SO2C2F5)2, LiN(SO2CF3)(SO2C4F9), and LiC(SO2CF3)3. One or more of these lithium salts can be used. Polymeric solid electrolytes may be gelled by the presence of an organic solvent.

[0040] Examples of complex hydride solid electrolytes include LiBH4-LiI and LiBH4-P2S5.

[0041] A mixture of two or more solid electrolytes selected from those described above may be used.

[0042] Insofar as the main component of the electrolyte contained in the power generation element 18 is a solid electrolyte, the power generation element 18 may further contain a non-aqueous electrolyte, a gel electrolyte, or an ionic liquid. "Main component" means the component that is present in the largest amount by mass.

[0043] The solid electrolyte may optionally contain a binder material. Examples of binder materials include polyvinylidene fluoride, polytetrafluoroethylene, polyethylene, polypropylene, aramid resin, polyamide, polyimide, polyamide-imide, polyacrylonitrile, polyacrylic acid, polymethyl acrylate, polyethyl acrylate, polyhexyl acrylate, polymethacrylic acid, polymethyl methacrylate, polyethyl methacrylate, polyhexyl methacrylate, polyvinyl acetate, polyvinylpyrrolidone, polyether, polyethersulfone, hexafluoropolypropylene, styrene-butadiene rubber, and carboxymethylcellulose. A copolymer of two or more materials selected from the group consisting of tetrafluoroethylene, hexafluoroethylene, hexafluoropropylene, perfluoroalkyl vinyl ether, vinylidene fluoride, chlorotrifluoroethylene, ethylene, propylene, pentafluoropropylene, fluoromethyl vinyl ether, acrylic acid, and hexadiene may be used as the binder material. A mixture of two or more binder materials selected from the above may be used.

[0044] The power generation element 18 may include a positive electrode active material. The positive electrode active material includes a material having the property of intercalating and releasing metal ions (e.g., lithium ions). Examples of positive electrode active materials include lithium-containing transition metal oxides, transition metal fluorides, polyanionic materials, fluorinated polyanionic materials, transition metal sulfides, transition metal oxysulfides, and transition metal oxynitrides. In particular, when a lithium-containing transition metal oxide is used as the positive electrode active material, manufacturing costs can be reduced and the average discharge voltage can be increased.

[0045] The power generation element 18 may contain a negative electrode active material. Examples of negative electrode active materials include metallic materials, carbon materials, oxides, nitrides, tin compounds, and silicon compounds. The metallic material may be a pure metal. The metallic material may be an alloy. Examples of metallic materials include lithium metal and lithium alloys. Examples of carbon materials include natural graphite, coke, carbon in the process of graphitization, carbon fibers, spheroidal carbon, artificial graphite, and amorphous carbon. From the viewpoint of capacity density, at least one selected from the group consisting of silicon (Si), tin (Sn), silicon compounds, and tin compounds is suitable as the negative electrode active material.

[0046] The power generation element 18 may include a current collector. Examples of materials for the current collector include copper, aluminum, nickel, iron, stainless steel, platinum, gold, and two or more alloys selected from these. The shape of the current collector may be, for example, a foil-like body, a plate-like body, or a mesh-like body. In addition to foil-like bodies, plate-like bodies, mesh-like bodies, etc., the current collector may include a connecting layer which is a layer containing a conductive material.

[0047] The metal part 12 of the tab lead 14 may be a long, plate-shaped or foil-shaped member made of a metal such as nickel, stainless steel, aluminum, or copper.

[0048] The resin portion 13 of the tab lead 14 is made of an insulating material that can be heat-sealed to both the metal portion 12 and the laminate film. The resin portion 13 may contain polypropylene, polyethylene, nylon, ethylene-vinyl acetate copolymer, polyethylene terephthalate, etc.

[0049] Laminate film has a laminated structure consisting of a resin layer made of a thermoplastic resin such as polyethylene or polypropylene and a metal layer made of a metal such as aluminum. In this laminated structure, both ends in the lamination direction are made of resin layers, and the metal layer is positioned between the resin layers.

[0050] In the example shown in Figure 1, the two tab leads 14 protrude from one of the four sides of the exterior material 15. However, the two tab leads 14 may protrude from different sides. For example, the two tab leads 14 may protrude from two opposing sides.

[0051] (Variation 1) Figure 4 is a diagram showing the configuration of the battery control system in Modification 1. In addition to the configuration of the control system 100 described with reference to Figures 1 to 3, the control system 101 is equipped with a cooling mechanism 34 for cooling the battery 10.

[0052] As shown in step S3 of Figure 3, when the temperature of the welded portion 16 reaches the threshold temperature T1, the control device 30 reduces the charging current value of the battery 10, reduces the discharge current value of the battery 10, or stops charging and discharging the battery 10. Along with the process in step S3, the control device 30 may also activate the cooling mechanism 34 or increase the cooling capacity of the cooling mechanism 34.

[0053] According to this modified example, the cooling mechanism 34 can be activated only when the temperature of the welded portion 16 becomes excessively high to cool the battery 10, or the cooling capacity of the cooling mechanism 34 can be increased. Therefore, the power consumption required to cool the battery 10 can be suppressed while ensuring the reliability of the battery 10. In addition, the temperature of the welded portion 16 can be rapidly reduced.

[0054] Cooling mechanisms 34 include air-cooling fans, water-cooling radiators, and Peltier coolers.

[0055] (Modification 2) Figure 5 is a diagram of the battery control system in modified example 2. In addition to the configuration of the control system 100 described with reference to Figures 1 to 3, the control system 102 includes a notification unit 30a that notifies the state of the battery 10 to the outside. In this modified example, the notification unit 30a is included in the control device 30. The notification unit 30a is, for example, a wired communication circuit or a wireless communication circuit.

[0056] As shown in step S3 of Figure 3, when the temperature of the welded portion 16 reaches the threshold temperature T1, the control device 30 reduces the charging current value of the battery 10, reduces the discharge current value of the battery 10, or stops charging and discharging the battery 10. Along with the processing in step S3, the notification unit 30a of the control device 30 notifies the user's terminal 36, the equipment 37 that operates on the power of the battery 10, etc., that the temperature of the welded portion 16 has reached the threshold temperature T1, and / or the temperature of the welded portion 16 itself.

[0057] According to this modified version, the temperature of the welded portion 16 and / or the fact that the temperature of the welded portion 16 has reached a threshold temperature T1 can be notified. By directly notifying the terminal 36 of this information, the user can be made aware of the possibility that the reliability of the battery 10 has deteriorated. By notifying the device 37 that operates on the power of the battery 10 of this information, the operation of the device 37 can be appropriately controlled based on this information. For example, the functions of the device 37 may be limited so as to suppress the power consumption of the battery 10.

[0058] (Variation 3) Figure 6 is a diagram showing the configuration of the battery control system in modified example 3. The control system 103 includes a second temperature sensor 22 in addition to the configuration of the control system 100 described with reference to Figures 1 to 3.

[0059] The second temperature sensor 22 detects the temperature near the connection point 19 between the power generation element 18 and the tab lead 14. The second temperature sensor 22 is located on the surface of the casing material 15 outside the battery 10. Specifically, when the battery 10 is viewed from above, the second temperature sensor 22 overlaps the connection point 19 between the power generation element 18 and the tab lead 14. The second temperature sensor 22 may also be located inside the battery 10.

[0060] The control device 30 controls the charging and discharging of the battery 10 based on the temperature of the welded portion 16 detected by the first temperature sensor 20 and the temperature near the connection portion 19 detected by the second temperature sensor 22.

[0061] During charging and discharging, when current flows, the temperature of the battery 10 rises due to self-heating caused by internal resistance. Because current concentrates at the connection point 19, the temperature of the connection point 19 may rise significantly more than that of other parts. Therefore, by detecting the temperature near the connection point 19 and controlling the charging and discharging of the battery 10 based on the detected temperature, the reliability of the battery 10 can be further improved.

[0062] The temperature of the welded portion 16 detected by the first temperature sensor 20 may be lower than the temperature near the connection portion 19 detected by the second temperature sensor 22.

[0063] As mentioned above, the concentration of current at the connection point 19 can cause the temperature of the connection point 19 to rise significantly more than the temperature of other parts. If the temperature of the welded part 16 rises due to heat conduction from the connection point 19 to the welded part 16, the temperature of the welded part 16 is expected to fall below the temperature near the connection point 19.

[0064] In the control system 103, a threshold temperature T2 is set in advance. When the temperature near the connection part 19 reaches the threshold temperature T2, the control device 30 reduces the charging current value of the battery 10, reduces the discharge current value of the battery, or stops charging and discharging the battery 10.

[0065] The temperature of the welded portion 16 can be an important indicator for determining the reliability of the battery 10. Heat generated at the connection portion 19 is conducted to the welded portion 16, and this heat causes the temperature of the welded portion 16 to rise. In other words, by detecting the temperature near the connection portion 19, it is possible to estimate the temperature rise of the welded portion 16 even before the temperature of the welded portion 16 actually rises. By controlling the charging and discharging of the battery 10 based on the temperature near the connection portion 19, an excessive temperature rise of the welded portion 16 can be suppressed. Therefore, according to this modified example, the reliability of the battery 10 can be further improved.

[0066] The threshold temperature T2 can be set arbitrarily. The threshold temperature T2 may be determined based on the relationship between the temperature near the connection part 19 and the temperature of the welded part 16 when the battery 10 self-heats, or it may be determined based on the information of the threshold temperature T1. In one example, the threshold temperature T2 is a temperature in the range of 50°C to 250°C. The threshold temperature T2 may also be a temperature expressed as (threshold temperature T1 + 10°C).

[0067] After the charging current value of battery 10 decreases, after the discharge current value of battery 10 decreases, or after charging and discharging of battery 10 stops, the second temperature sensor 22 re-detects the temperature near the connection part 19. If the temperature near the connection part 19 is lower than the threshold temperature T2, the control device 30 increases the charging current value of battery 10, increases the discharge current value of battery 10, or restarts charging and discharging of battery 10.

[0068] After the temperature near the connection point 19 reaches a temperature at which the battery 10 can operate safely, the charging current value can be increased, the discharging current value can be increased, or charging or discharging can be restarted, thereby efficiently controlling the charging and discharging of the battery 10 while ensuring the reliability of the battery 10.

[0069] Figure 7 is a flowchart of the control performed by the control device 30. The control device 30 periodically performs each of the processes shown in the flowchart of Figure 7. The control device 30 performs each of the processes shown in the flowchart of Figure 3 and each of the processes shown in the flowchart of Figure 7 in parallel. In parallel with monitoring the temperature of the welded portion 16, the control device 30 monitors the temperature near the connection portion 19.

[0070] In step ST1, the temperature near the connection part 19 is detected.

[0071] In step ST2, it is determined whether the temperature near the connection part 19 is equal to or greater than the threshold temperature T2. If the temperature near the connection part 19 is equal to or greater than the threshold temperature T2, in step ST3, charging or discharging of the battery 10 is stopped. Instead of stopping charging or discharging, the charging current value of the battery 10 may be reduced, or the discharging current value of the battery 10 may be reduced.

[0072] After charging or discharging stops, in step ST4, the system waits for a predetermined time. The "predetermined time" is the time it is expected that the temperature near the connection part 19 will have decreased sufficiently. In one example, the "predetermined time" is in the range of 1 second to 3600 seconds.

[0073] After a predetermined time has elapsed, in step ST5, the temperature near the connection part 19 is detected again.

[0074] In step ST6, it is determined whether the temperature near the connection 19 is below the threshold temperature T2. If the temperature near the connection 19 is lower than the threshold temperature T2, charging or discharging is resumed in step ST7. Instead of resuming charging or discharging, the charging current value of the battery 10 may be increased, or the discharging current value of the battery 10 may be increased.

[0075] (Modification 4) Figure 8 is a diagram showing the configuration of the battery control system in modified example 4. The control system 104 includes a gas sensor 38 in addition to the configuration of the control system 103 described with reference to Figure 6. The gas sensor 38 may be pre-installed in the environment in which the battery 10 is used.

[0076] Figure 9 is a graph showing the relationship between the temperature of the welded portion 16 and time. At time ta, if the temperature of the welded portion 16 exceeds the threshold temperature T1, the control device 30 reduces the charging current value of the battery 10, reduces the discharge current value of the battery 10, or stops charging and discharging the battery 10. After that, the temperature of the welded portion 16 decreases. At time tb, if the temperature of the welded portion 16 reaches a threshold temperature T3, which is lower than the threshold temperature T1, the gas sensor 38 detects the gas concentration in the environment surrounding the battery 10. If the detected gas concentration is less than or equal to the threshold concentration G1, the control device 30 increases the charging current value of the battery 10, increases the discharge current value of the battery 10, or restarts charging and discharging the battery 10. In other words, in the flowchart shown in Figure 3, between the processing of step S6 and the processing of step S7, the process of detecting the gas concentration and the process of determining whether the detected gas concentration is less than or equal to the threshold concentration G1 are performed.

[0077] The threshold temperature T1 can be set based on the melting point of the internal resin layer of the laminate film, the softening point of the internal resin layer of the laminate film, the temperature at which the adhesive strength of the welded portion 16 decreases, or the temperature at which the welded portion 16 melts and its airtightness is compromised. In this case, if the welded portion 16 exceeds the threshold temperature T1, the airtightness of the welded portion 16 is compromised, and gas generated from the power generation element 18 may leak into the surrounding environment of the battery 10. Even if the welded portion 16 melts and a void is formed, it is difficult to inspect the shape of the welded portion 16. However, it is possible to detect the gas concentration in the surrounding environment of the battery 10. By detecting the gas concentration in the surrounding environment of the battery 10, it is possible to indirectly check whether the airtightness of the welded portion 16 is maintained. If the gas concentration in the surrounding environment of the battery 10 is less than or equal to the gas concentration G1 at which it can be determined that there is no gas leakage from the battery 10, it can be determined that the welded portion 16 is in a normal state with maintained airtightness. In this case, the control device 30 increases the charging current value of the battery 10, increases the discharge current value of the battery 10, or restarts the charging and discharging of the battery 10. According to this modified example, the charging and discharging of the battery 10 can be efficiently controlled while ensuring the reliability of the battery 10.

[0078] The threshold temperature T3 shown in Figure 9 is, for example, 1°C to 200°C lower than the threshold temperature T1.

[0079] Similar technology can also be applied to the temperature near the connection point 19.

[0080] In other words, when the temperature near the connection part 19 reaches a threshold temperature T4, which is lower than the threshold temperature T2, the gas sensor 38 detects the gas concentration in the environment surrounding the battery 10. If the gas concentration is less than or equal to the threshold concentration G1, the control device 30 increases the charging current value of the battery 10, increases the discharging current value of the battery 10, or restarts charging and discharging of the battery 10.

[0081] As described above, the temperature rise of the welded portion 16 can be estimated by detecting the temperature near the connection portion 19. After the temperature near the connection portion 19 exceeds the threshold temperature T2, and reaches a threshold temperature T4 (a temperature below the threshold temperature T2), that is, after reaching a temperature at which the battery 10 can operate safely, the gas concentration in the surrounding environment of the battery 10 is measured. This allows for indirect inspection of whether the airtightness of the welded portion 16 is maintained. With this configuration, the charging and discharging of the battery 10 can be efficiently controlled while ensuring the reliability of the battery 10.

[0082] The threshold temperature T4 is, for example, 1°C to 200°C lower than the threshold temperature T2.

[0083] Examples of gases whose concentration can be detected by the gas sensor 38 include hydrogen sulfide, carbon monoxide, hydrogen, hydrogen chloride, and halogen gases.

[0084] (others) The embodiments and their respective modifications can be combined with each other insofar as they do not conflict with the technical standards. For example, the cooling mechanism 34 of the control system 101 described with reference to Figure 4 may be provided in other control systems. The notification unit 30a of the control system 102 described with reference to Figure 5 may be provided in other control systems.

[0085] (Other embodiments) (Note) The above description of embodiments discloses the following technologies.

[0086] (Technology 1) Batteries and First temperature sensor and, Control device and Equipped with, The aforementioned battery includes a power generation element, a tab lead comprising a resin part and a metal part, and an outer casing material including a laminate film. The outer periphery of the exterior material includes a welded portion, The first temperature sensor detects the temperature of the welded portion, The control device controls the charging and discharging of the battery based on the temperature of the welded portion detected by the first temperature sensor. Battery control system.

[0087] The control system disclosed herein can improve the reliability of batteries, including those with laminated film casings.

[0088] (Technology 2) The battery control system according to Technology 1, wherein the welded portion includes a tab welded portion which is the connection portion between the resin portion of the tab lead and the laminate film, and the first temperature sensor detects the temperature of the tab welded portion. By appropriately controlling the charging and discharging of the battery based on the temperature near the tab welded portion, the reliability of the battery can be further improved.

[0089] (Technology 3) A battery control system according to Technology 1 or 2, wherein when the temperature of the welded portion reaches a threshold temperature T1, the control device reduces the charging current value of the battery, reduces the discharge current value of the battery, or stops charging and discharging the battery. Such control can suppress the temperature of the welded portion from rising excessively, thereby further improving the reliability of the battery.

[0090] (Technology 4) A battery control system according to Technology 3, wherein after a decrease in the charging current value of the battery, after a decrease in the discharge current value of the battery, or after charging and discharging of the battery is stopped, the temperature of the welded portion is re-detected by the first temperature sensor, and if the temperature of the welded portion is lower than the threshold temperature T1, the control device increases the charging current value of the battery, increases the discharge current value of the battery, or restarts charging and discharging of the battery. With such a configuration, it is possible to efficiently control the charging and discharging of the battery while ensuring the reliability of the battery.

[0091] (Technology 5) A battery control system according to any one of the technologies 1 to 4, further comprising a cooling mechanism for cooling the battery, wherein when the temperature of the welded portion reaches a threshold temperature T1, the control device activates the cooling mechanism or increases the cooling capacity of the cooling mechanism. With such a configuration, the temperature of the welded portion can be rapidly reduced.

[0092] (Technology 6) A battery control system according to any one of the technologies 1 to 5, further comprising a notification unit for notifying the state of the battery to the outside, wherein when the temperature of the welded portion reaches a threshold temperature T1, the notification unit notifies that the temperature of the welded portion has reached the threshold temperature T1 and / or the temperature of the welded portion. With such a configuration, it is possible to notify the temperature of the welded portion and / or the fact that the temperature of the welded portion has reached a threshold temperature T1.

[0093] (Technology 7) A battery control system according to any one of the technologies 1 to 6, further comprising a second temperature sensor, the second temperature sensor detecting the temperature near the connection between the power generation element and the tab lead, and the control device controlling the charging and discharging of the battery based on the temperature of the weld and the temperature near the connection. By detecting the temperature near the connection and controlling the charging and discharging of the battery based on the detected temperature, the reliability of the battery can be further improved.

[0094] (Technology 8) The battery control system according to Technical Reference 7, wherein the temperature of the welded portion detected by the first temperature sensor is lower than the temperature near the connection portion detected by the second temperature sensor.

[0095] (Technology 9) A battery control system according to Technology 7 or 8, wherein when the temperature near the connection reaches a threshold temperature T2, the control device reduces the charging current value of the battery, reduces the discharge current value of the battery, or stops charging and discharging the battery. With such a configuration, the reliability of the battery can be further improved.

[0096] (Technology 10) A battery control system according to Technology 9, wherein after a decrease in the charging current value of the battery, after a decrease in the discharge current value of the battery, or after charging and discharging of the battery is stopped, the second temperature sensor re-detects the temperature near the connection part, and if the temperature near the connection part is lower than the threshold temperature T2, the control device increases the charging current value of the battery, increases the discharge current value of the battery, or restarts charging and discharging of the battery. With such a configuration, it is possible to efficiently control the charging and discharging of the battery while ensuring the reliability of the battery.

[0097] (Technology 11) A battery control system according to Technology 3, wherein when the temperature of the welded portion reaches a threshold temperature T3 which is lower than the threshold temperature T1, a gas sensor detects the gas concentration in the environment surrounding the battery, and if the gas concentration is less than or equal to the threshold concentration G1, the control device increases the charging current value of the battery, increases the discharge current value of the battery, or restarts charging and discharging of the battery. With such a configuration, the charging and discharging of the battery can be efficiently controlled while ensuring the reliability of the battery.

[0098] (Technology 12) A battery control system according to Technology 9, wherein when the temperature near the connection reaches a threshold temperature T4 which is lower than the threshold temperature T2, a gas sensor detects the gas concentration in the environment surrounding the battery, and if the gas concentration is less than or equal to the threshold concentration G1, the control device increases the charging current value of the battery, increases the discharge current value of the battery, or restarts charging and discharging of the battery. With such a configuration, the charging and discharging of the battery can be efficiently controlled while ensuring the reliability of the battery.

[0099] (Technology 13) A battery control system according to any one of the technologies 1 to 12, wherein the power generation element includes a solid electrolyte. By applying the technology of this disclosure to a battery in which the power generation element includes a solid electrolyte, the reliability of the battery can be more effectively improved.

[0100] (Technology 14) To detect the temperature of the welded portion of the exterior material, including the laminate film, The charging and discharging of the battery is controlled based on the temperature detection result, A method for controlling a battery, including the control of the battery.

[0101] The control method disclosed herein can improve the reliability of batteries, including those with laminated film exteriors.

[0102] (Technology 15) The battery control method according to Technical Reference 14, wherein the battery comprises a tab lead having a resin portion and a metal portion, and the welded portion includes a tab welded portion which is a connection portion between the resin portion and the laminate film. The reliability of the battery can be further improved by appropriately controlling the charging and discharging of the battery based on the temperature near the tab welded portion.

[0103] (Technology 16) A battery control method according to Technology 14 or 15, wherein when the temperature of the welded portion reaches a threshold temperature T1, the charging current value of the battery is reduced, the discharge current value of the battery is reduced, or the charging and discharging of the battery is stopped. Such control can suppress the temperature of the welded portion from rising excessively, thereby further improving the reliability of the battery.

[0104] (Technology 17) The temperature of the welded area of ​​the exterior material, including the laminate film, is detected. Based on the temperature detection result, the charging and discharging of the battery is controlled. Battery control device.

[0105] The control device of this disclosure can improve the reliability of a battery including an outer casing made of laminate film. [Industrial applicability]

[0106] The technology disclosed herein is useful for controlling secondary batteries, such as all-solid-state batteries used in electronic devices, electrical appliances, automobiles, and the like. [Explanation of Symbols]

[0107] 10 batteries 12 Metal parts 13 Resin part 14 Tabread 15 Exterior materials 16 Welded area 17 Tab welding section 18 Power generation elements 19 Connection part 20. First temperature sensor 22 Second temperature sensor 30 Control device 30a Notification section 32 Power supply circuit 34 Cooling mechanism 36 terminals 37 Equipment 38 Gas Sensor 100, 101, 102, 103, 104 Control System

Claims

1. Batteries and First temperature sensor and Control device and Equipped with, The aforementioned battery includes a power generation element, a tab lead comprising a resin part and a metal part, and an outer casing material including a laminate film. The outer periphery of the exterior material includes a welded portion, The first temperature sensor detects the temperature of the welded portion, The control device controls the charging and discharging of the battery based on the temperature of the welded portion detected by the first temperature sensor. Battery control system.

2. The welding portion includes a tab welding portion which is the connection portion between the resin portion of the tab lead and the laminate film. The first temperature sensor detects the temperature of the tab welded portion. A battery control system according to claim 1.

3. When the temperature of the welded portion reaches a threshold temperature T1, the control device reduces the charging current value of the battery, reduces the discharging current value of the battery, or stops charging and discharging the battery. A battery control system according to claim 1.

4. After the charging current value of the battery decreases, after the discharge current value of the battery decreases, or after charging and discharging of the battery stops, the temperature of the welded portion is re-detected by the first temperature sensor. If the temperature of the welded portion is lower than the threshold temperature T1, the control device increases the charging current value of the battery, increases the discharging current value of the battery, or restarts charging and discharging of the battery. The battery control system according to claim 3.

5. The battery is further provided with a cooling mechanism, When the temperature of the welded portion reaches a threshold temperature T1, the control device activates the cooling mechanism or increases the cooling capacity of the cooling mechanism. A battery control system according to claim 1.

6. The system further includes a notification unit that notifies the external system of the battery status, When the temperature of the welded portion reaches the threshold temperature T1, the notification unit notifies that the temperature of the welded portion has reached the threshold temperature T1 and / or the temperature of the welded portion. A battery control system according to claim 1.

7. Furthermore, it is equipped with a second temperature sensor, The second temperature sensor detects the temperature near the connection between the power generation element and the tab lead. The control device controls the charging and discharging of the battery based on the temperature of the welded portion and the temperature near the connection portion. A battery control system according to claim 1.

8. The temperature of the welded portion detected by the first temperature sensor is lower than the temperature near the connection portion detected by the second temperature sensor. The battery control system according to claim 7.

9. When the temperature near the connection reaches a threshold temperature T2, the control device reduces the charging current of the battery, reduces the discharge current of the battery, or stops charging and discharging the battery. A battery control system according to claim 7.

10. After the charging current value of the battery decreases, after the discharge current value of the battery decreases, or after charging and discharging of the battery stops, the temperature near the connection part is re-detected by the second temperature sensor. If the temperature near the connection is lower than the threshold temperature T2, the control device increases the charging current of the battery, increases the discharging current of the battery, or restarts charging and discharging the battery. A battery control system according to claim 9.

11. When the temperature of the welded portion reaches a threshold temperature T3 which is lower than the threshold temperature T1, the gas sensor detects the gas concentration in the surrounding environment of the battery. If the gas concentration is less than or equal to the threshold concentration G1, the control device increases the charging current value of the battery, increases the discharging current value of the battery, or restarts charging and discharging of the battery. The battery control system according to claim 3.

12. When the temperature near the connection reaches a threshold temperature T4 which is lower than the threshold temperature T2, the gas sensor detects the gas concentration in the surrounding environment of the battery. If the gas concentration is less than or equal to the threshold concentration G1, the control device increases the charging current value of the battery, increases the discharging current value of the battery, or restarts charging and discharging of the battery. A battery control system according to claim 9.

13. The power generation element includes a solid electrolyte. A battery control system according to claim 1.

14. To detect the temperature of the welded portion of the exterior material, including the laminate film, The charging and discharging of the battery is controlled based on the temperature detection result, A method for controlling a battery, including the control of the battery.

15. The aforementioned battery comprises a tab lead having a resin part and a metal part, The welded portion includes a tab welded portion which is the connection portion between the resin portion and the laminate film. The battery control method according to claim 14.

16. When the temperature of the welded portion reaches a threshold temperature T1, the charging current value of the battery is reduced, the discharging current value of the battery is reduced, or the charging and discharging of the battery is stopped. The battery control method according to claim 14.

17. The temperature of the welded area of ​​the exterior material, including the laminate film, is detected. Based on the temperature detection result, the charging and discharging of the battery is controlled. Battery control device.

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