Battery housing body and battery pack

Abstract

A battery housing body 1 includes: a housing 11 which has an intake port 11a and an exhaust port 11b and houses at least one battery cell 2; a blowing part 14 which generates a flow of air from the intake port 11a to the exhaust port 11b inside the housing 11; and an active gas removal part 15 which removes active gas generated from at least one battery cell 2 and discharged from the exhaust port 11b by a flow of air.

Description

Battery container and battery pack

[0001] The present invention relates to a battery containing body and a battery pack.

[0002] In recent years, sulfide-based solid electrolytes exhibiting high ionic conductivity have been developed as solid electrolytes for use in all-solid-state batteries. However, sulfide-based solid electrolytes may react with water to generate hydrogen sulfide, and therefore, measures to combat this hydrogen sulfide are an issue for practical application of all-solid-state batteries using sulfide-based solid electrolytes. Patent Literature 1 describes a technology for preventing hydrogen sulfide generated inside a housing from leaking to the outside by providing a hydrogen sulfide removal unit at a communication port between the housing and the outside, which houses a battery cell.

[0003] JP 2018-73802 A

[0004] However, the technology described in Patent Document 1 does not take into consideration the impact of continued generation of hydrogen sulfide. Specifically, it does not consider the possibility that, when the hydrogen sulfide concentration inside the housing rises to a certain level, hydrogen sulfide as a flammable gas may react with oxygen and burn, or that hydrogen sulfide as a corrosive gas may corrode the materials of the battery cell and its accessories (such as electrode terminals and electrical circuits). This gas retention problem may also occur when other active gases besides hydrogen sulfide are generated. It may also occur when various other active gases are generated in batteries other than all-solid-state batteries containing sulfide-based solid electrolytes. Therefore, a solution that can be applied to such a wide variety of active gases is needed.

[0005] Therefore, an object of the present invention is to provide a battery containing body and a battery pack that prevent active gas generated inside from leaking to the outside and also prevent the active gas from accumulating inside.

[0006] In order to achieve the above-mentioned object, the battery housing of the present invention has a housing having an air intake port and an exhaust port and housing at least one battery cell, an air blowing section that generates an air flow from the air intake port toward the exhaust port inside the housing, and an active gas removal section that removes active gas generated from the at least one battery cell and discharged from the exhaust port by the air flow.

[0007] A battery pack of the present invention includes at least one battery cell, the battery containing body, and a control unit that controls the at least one battery cell.

[0008] With this battery containing body and battery pack, air is circulated from the air intake port toward the exhaust port inside the housing, thereby preventing active gases generated from the battery cells from accumulating inside the housing. This prevents the concentration of active gases inside the housing from increasing, reducing the possibility that the active gases will have adverse effects inside the housing. Furthermore, such active gases are removed by the active gas removal unit as they flow through the exhaust piping, preventing them from leaking to the outside.

[0009] As described above, according to the present invention, it is possible to prevent active gas generated inside the battery containing body and the battery pack from leaking to the outside, and it is also possible to prevent the active gas from accumulating inside.

[0010] Fig. 1 is a schematic configuration diagram of a battery pack according to a first embodiment of the present invention; Fig. 2 is a schematic configuration diagram of a battery pack according to a second embodiment of the present invention; Fig. 3 is a schematic configuration diagram of a battery pack according to a third embodiment of the present invention; Fig. 4 is a schematic configuration diagram of a battery pack according to a fourth embodiment of the present invention; and Fig. 5 is a schematic configuration diagram of a battery pack according to a fifth embodiment of the present invention.

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Configurations common to each embodiment will be denoted by the same reference numerals in the drawings, and duplicated descriptions will be omitted as appropriate. Furthermore, as may be mentioned again below, characteristic configurations and modifications of each embodiment can also be applied to other embodiments as long as they are not mutually inconsistent.

[0012] In the following embodiments, an all-solid-state battery containing a sulfide-based solid electrolyte is exemplified as a battery cell that can generate an active gas, and hydrogen sulfide, which is flammable and corrosive, is exemplified as an active gas to be removed by the present invention, but the present invention is not limited thereto. In other words, the active gas to be removed by the present invention may be an active gas other than hydrogen sulfide generated by an all-solid-state battery containing a sulfide-based solid electrolyte. In this context, the term "active gas" broadly means a gas that can chemically react with other elements or compounds. Examples of such active gases include sulfur (S, S) and sulfur (S). ２ , S ８ Examples of such active gases include sulfur oxides (sulfur monoxide, sulfur dioxide, sulfur trioxide, etc.), halogens (fluorine, chlorine, bromine, iodine, etc.), oxygen, and carbon dioxide. Alternatively, the active gases may be those generated by other types of batteries, such as hydrogen, carbon dioxide, methane, ethane, ethylene, hydrogen fluoride, and carbon monoxide generated by lithium-ion batteries; fluorine and hydrogen fluoride generated by fluoride batteries; hydrogen and oxygen generated by aqueous batteries such as aqueous lithium-ion batteries and zinc-negative battery batteries; and sulfur dioxide generated by inorganic electrolyte batteries. On the other hand, the active gas targeted for removal by the present invention may be the vaporized gas of an organic solvent used in the nonaqueous electrolyte of a lithium-ion battery. Examples of such organic solvents include ethylene carbonate, propylene carbonate, fluoroethylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, γ-butyrolactone, and propyl propionate.

[0013] First Embodiment FIG. 1 is a schematic diagram showing the configuration of a battery pack according to a first embodiment of the present invention.

[0014] The battery pack 1 includes a plurality of battery cells 2 and at least one pair of electrode terminals (not shown). The battery cells 2 are electrically connected to one another. The connection configuration is not particularly limited and may be serial or parallel, or a combination thereof. At least a portion of the battery cells 2 may be restrained by a restraining member. At least one pair of electrode terminals is electrically connected to the battery cells 2 by an electrical circuit (not shown) so that power can be extracted from the battery cells 2. While FIG. 1 shows four battery cells 2, the number of battery cells 2 included in the battery pack 1 is not limited to this. The battery pack 1 may include a plurality of battery modules (battery assemblies), each including a plurality of battery cells 2. That is, the battery cells 2 may be modularized to form a battery module, and the battery pack 1 may be composed of a plurality of battery modules combined together.

[0015] The battery cell 2 is an all-solid-state battery and includes a positive electrode, a negative electrode, and a solid electrolyte layer disposed between the positive electrode and the negative electrode. For example, the positive electrode includes a positive electrode current collector and a positive electrode active material layer, and the negative electrode includes a negative electrode current collector and a negative electrode active material layer. The positive electrode current collector, the positive electrode active material layer, the solid electrolyte layer, the negative electrode active material layer, and the negative electrode current collector are stacked in this order to form a laminate, which is housed in a battery case of a laminate type, a cylindrical type, a prismatic type, or the like. A reinforcing layer made of a curable resin may be provided around the laminate, if necessary.

[0016] The positive electrode current collector and the negative electrode current collector can be made of known materials commonly used in all-solid-state batteries. The positive electrode current collector can be made of metal materials such as aluminum, stainless steel, and titanium, and can be in the form of, for example, foil, film, sheet, or mesh. The negative electrode current collector can be made of metal materials such as stainless steel, nickel, and copper, and can be in the form of, for example, foil, film, or sheet.

[0017] The positive electrode active material layer contains at least a positive electrode active material, and the negative electrode active material layer contains at least a negative electrode active material. The positive electrode active material is not particularly limited as long as it is a material that absorbs and releases metal ions such as lithium ions, and examples thereof include sulfur, lithium-containing transition metal oxides, transition metal fluorides, polyanion compounds, and transition metal sulfides. The negative electrode active material is not particularly limited as long as it is a material that absorbs and releases metal ions such as lithium ions, and examples thereof include metallic lithium, metals or alloys that can be alloyed with lithium, carbon materials such as graphite and hard carbon, transition metal oxides, transition metal sulfides, and silicon. The positive electrode active material layer and the negative electrode active material layer may each contain a solid electrolyte, a binder, or the like, as appropriate.

[0018] The solid electrolyte layer contains at least a sulfide-based solid electrolyte. The sulfide solid electrolyte may be, for example, Li ２ S-SiS ２ system, Li ２ S-B ２ S ３ system, Li ２ S-P ２ S ３ system, Li ２ S-P ２ S ５ system, Li ２ S-GeS ２ system, Li ２ S-B ２ S ３ system, Li ３ P.O. ４ -P ２ S ５ system, Li ４ SiO ４ -Li ２ S-SiS ２ Glasses or glass ceramics such as Li-based ３．２５ Ge ０．２５ P ０．７５ S ４ , Li １０ GeP ２ S １２ In addition, LiCl, LiBr, LiI, Li ｘ MO ｙ(wherein M is any of P, Si, Ge, B, Al, Ga, and In, and x and y are natural numbers) may be added, and a material that has been further heat-treated may also be used. The solid electrolyte layer may contain a binder or the like as appropriate, and may contain a type of solid electrolyte different from the sulfide-based solid electrolyte. Examples of such solid electrolytes include halide-based solid electrolytes, oxide-based solid electrolytes, polymer-based solid electrolytes, hydride-based solid electrolytes, and nitride-based solid electrolytes.

[0019] The battery pack 1 also has a battery containing body 3 that contains a plurality of battery cells 2. The battery containing body 3 is composed of a housing 11, an intake pipe 12, an exhaust pipe 13, an air blower 14, and a hydrogen sulfide removal unit (active gas removal unit) 15.

[0020] The housing 11 functions to accommodate multiple battery cells 2 while extending at least one pair of electrode terminals (not shown) to the outside. The housing 11 is provided with an air intake 11a for introducing air into the housing 11 and an air exhaust 11b for expelling air from the housing 11. Fillers such as elastic materials, heat transfer materials, and insulating materials may be appropriately disposed inside the housing 11 in gaps between the battery cells 2 or between the battery cells 2 and the restraining members. While FIG. 1 shows a simplified view, considering heat dissipation from the battery cells 2, it is preferable that the multiple battery cells 2 are accommodated in the housing 11 with at least a portion of the battery cells 2 in direct or indirect contact with the housing 11 (e.g., via the restraining members). The shape of the housing 11 is not particularly limited and can be arbitrarily set depending on the shape and arrangement of the battery cells 2 to be accommodated. As described above, the housing 11 may accommodate multiple battery modules, each of which includes multiple battery cells 2.

[0021] One end (downstream end) of the intake pipe 12 is connected to the intake port 11a of the housing 11 via an on-off valve (not shown). One end (upstream end) of the exhaust pipe 13 is connected to the exhaust port 11b of the housing 11 via an on-off valve (not shown). The connection positions of the intake pipe 12 and the exhaust pipe 13 to the housing 11 (i.e., the positions of the intake port 11a and the exhaust port 11b in the housing 11) are not particularly limited, but are preferably positioned opposite each other to ensure uniform air circulation inside the housing 11. The intake pipe 12 may be provided with a filtering means such as an air filter to prevent foreign matter from entering from the outside.

[0022] The blower 14 is provided in the exhaust pipe 13 and has the function of generating an air flow inside the housing 11. The blower 14 is not particularly limited, and may be, for example, a fan, a blower, a pump, or a compressor. In this case, the output of the blower 14 is controlled by the control unit 4, which will be described later, and the blower 14 may have the function of adjusting the flow rate of air flowing into the housing 11. Note that, in order to drive the blower 14, power may be supplied to the blower 14 from the battery cells 2. Alternatively, a separate, independent power source may be provided, which allows the blower 14 to be reliably driven even in a situation where the output of the battery cells 2 must be limited or stopped, as will be described later.

[0023] The hydrogen sulfide removal unit 15 is provided in the exhaust pipe 13 and functions to remove hydrogen sulfide (active gas) generated when the sulfide-based solid electrolyte contained in the battery cell 2 reacts with water. The hydrogen sulfide removal unit 15 is not particularly limited, and may be, for example, a cylindrical container made of a metal such as stainless steel filled with a hydrogen sulfide removal agent. Examples of such removal agents include known agents commonly used to remove hydrogen sulfide, such as ion exchange resins, activated carbon (particularly activated carbon impregnated with a basic compound such as sodium hydroxide or potassium carbonate), activated alumina (particularly activated alumina impregnated with potassium permanganate), zeolites, basic solids such as calcium oxide or calcium carbonate, basic liquids such as aqueous sodium hydroxide or aqueous sodium carbonate, and ionic liquids having a reactive site with acids such as amino groups. Because hydrogen sulfide may reach a temperature higher than room temperature due to heat generation in the battery cell 2, the hydrogen sulfide removal agent is preferably one that can maintain its hydrogen sulfide removal performance even at high temperatures, and more preferably one whose removal mechanism is based on an irreversible reaction. This allows hydrogen sulfide to be reliably removed even at high temperatures, and also prevents the removed hydrogen sulfide from being re-released. Note that some removers may generate powder depending on the environment in which the battery pack 1 is used (for example, when the battery pack 1 is used in an electric vehicle and is subjected to vibration). In such cases, a filtering means such as an air filter may be installed downstream of the hydrogen sulfide removal section 15. This prevents the powder from leaking to the outside and also prevents the powder from blocking the air flow or causing a dust explosion.

[0024] With this configuration, the air blower 14 can circulate air inside the casing 11 from the intake pipe 12 toward the exhaust pipe 13. Therefore, even if hydrogen sulfide is generated from the battery cells 2, it is possible to prevent the hydrogen sulfide from remaining inside the casing 11 and increasing the hydrogen sulfide concentration inside the casing 11. As a result, it is possible to reduce the possibility that hydrogen sulfide, as a flammable gas, will react with oxygen inside the casing 11 and burn, or that hydrogen sulfide, as a corrosive gas, will corrode the materials of the battery cells 2. Furthermore, such hydrogen sulfide is removed by the hydrogen sulfide removal unit 15 when it is discharged from the inside of the casing 11 by the air flow and flows through the exhaust pipe 13, so it does not leak to the outside. Even if other active gases with different densities from hydrogen sulfide are generated from the battery cells 2, they can be reliably discharged by forcibly generating an air flow inside the casing 11 using the air blower 14. Therefore, the above-described configuration of this embodiment can be suitably used even when the battery cells 2 are batteries other than all-solid-state batteries, thereby preventing a wide variety of active gases from remaining inside the casing 11.

[0025] In the illustrated example, the blower 14 is provided in the exhaust pipe 13. However, its location is not particularly limited as long as it can generate an air flow inside the housing 11. For example, it may be provided in the intake pipe 12 or inside the housing 11. If the blower 14 is provided in the intake pipe 12, the on-off valve (not shown) of the exhaust pipe 13 may be adjustable to any opening degree. This makes it possible to increase the pressure inside the housing 11 and reduce the amount of hydrogen sulfide released from the battery cell 2 by reducing the opening degree when hydrogen sulfide is generated from the battery cell 2. Furthermore, if the blower 14 is provided in the intake pipe 12 or inside the housing 11, an exhaust pipe separate from the exhaust pipe 13 may be connected to the housing 11 (via an on-off valve), thereby enabling selection of the hydrogen sulfide exhaust route. As a result, if discharging hydrogen sulfide to the outside would have little impact on the surrounding area, hydrogen sulfide can be discharged without passing through the hydrogen sulfide removal unit 15, thereby suppressing deterioration of the hydrogen sulfide removal unit 15. Alternatively, even if the blower 14 is provided in the exhaust pipe 13, the same effect can be obtained if, for example, the exhaust pipe 13 branches into two downstream (via a three-way valve) and the hydrogen sulfide removal unit 15 is provided in one of the branches.

[0026] Although the air flow by the blower 14 may be constant, doing so may adversely promote contact between the moisture and oxygen contained in the air introduced into the housing 11 and the battery cells 2. Therefore, from the viewpoint of reducing the power consumption of the blower 14, it is preferable that the on-off valves (not shown) of the intake pipe 12 and the exhaust pipe 13 are normally closed and the blower 14 is not operating. Then, when hydrogen sulfide is generated from the battery cells 2, it is preferable that the air flow by the blower 14 be started in response to this. That is, it is preferable that the on-off valves of the intake pipe 12 and the exhaust pipe 13 be opened and the blower 14 be operated in response to the generation of hydrogen sulfide from the battery cells 2. For this purpose, the battery pack 1 has a hydrogen sulfide sensor (gas sensor) 16 and a control unit 4.

[0027] The hydrogen sulfide sensor 16 has a function of detecting the presence or concentration of hydrogen sulfide within the housing 11. The hydrogen sulfide sensor 16 is not particularly limited, and known hydrogen sulfide sensors, such as those based on potentiostatic electrolysis, semiconductor technology, thermal conduction, and electrical resistance, can be used. The location of the hydrogen sulfide sensor 16 is not limited to the location shown in the figure, as long as it can detect the presence or concentration of hydrogen sulfide within the housing 11. In the example shown in the figure, only one hydrogen sulfide sensor 16 is installed in the housing 11, but multiple hydrogen sulfide sensors 16 may be installed. In this case, a hydrogen sulfide sensor 16 may be installed near each battery cell 2. One of the multiple hydrogen sulfide sensors 16 may be installed downstream of the hydrogen sulfide removal unit 15 to detect whether the removing agent described above has broken through. When multiple hydrogen sulfide sensors 16 are used, they may be the same type, but preferably different types. This allows the validity of the detection results of one hydrogen sulfide sensor 16 to be evaluated using another hydrogen sulfide sensor 16 of a different type, and makes it possible to diagnose, for example, whether the hydrogen sulfide sensor 16 is malfunctioning due to the influence of coexisting gases.

[0028] The control unit 4 has a function of controlling the blower 14 based on the detection result of the hydrogen sulfide sensor 16. Specifically, when hydrogen sulfide is detected by the hydrogen sulfide sensor 16, the control unit 4 opens the on-off valves of the intake pipe 12 and the exhaust pipe 13 and operates the blower 14 to generate an air flow inside the housing 11. Even if the flammable hydrogen sulfide gas is generated inside the housing 11, combustion of the hydrogen sulfide will not occur unless its concentration reaches the flammable range. Therefore, the control unit 4 may control the blower 14 to adjust the flow rate of air flowing into the housing 11, i.e., adjust the amount of gas containing hydrogen sulfide flowing out of the housing 11, so that the hydrogen sulfide concentration detected by the hydrogen sulfide sensor 16 is below the lower flammable limit. Alternatively, from the perspective of reducing power consumption of the blower 14, the control unit 4 may close the on-off valves of the intake pipe 12 and the exhaust pipe 13 and stop operation of the blower 14 when the hydrogen sulfide concentration detected by the hydrogen sulfide sensor 16 falls sufficiently below the lower flammable limit. The control unit 4 also has a function of controlling the output of the battery cells 2. For example, when hydrogen sulfide is detected by the hydrogen sulfide sensor 16, the control unit 4 can limit or stop the output of at least some of the battery cells 2 for safety reasons. The control unit 4 may also store the detection result of the hydrogen sulfide sensor 16 for immediate or future use, or transmit it to a server or a blockchain network. If the control unit 4 detects that the hydrogen sulfide removal unit 15 has broken through, as described above, the control unit 4 may output a notification to notify the user of this.

[0029] As described above, it is preferable to start the air flow by operating the blower 14 in conjunction with the detection of hydrogen sulfide, but this does not necessarily apply when the battery cells 2 are stopped for an extended period of time. That is, if the air flow by the blower 14 is stopped while the battery cells 2 are stopped for an extended period of time and hydrogen sulfide accumulates inside the housing 11 for some reason, sparks or heat generated when the battery cells 2 are started may become an ignition source and cause the hydrogen sulfide to burn. In consideration of this possibility, it is preferable that the air flow by the blower 14 be started at the latest before the battery cells 2 are started, and from this perspective, it is also preferable to provide a separate, independent power source for driving the blower 14, as described above.

[0030] Furthermore, if air is not constantly circulated by the blower 14, the other components (gas flow members) 12-15 of the battery containing body 3, excluding the housing 11, may be detachably attached to the housing 11 in order to reduce the number of parts. Thus, the gas flow members 12-15 may be normally detached and attached to the housing 11 so that air flow by the blower 14 can be initiated when hydrogen sulfide is detected by the hydrogen sulfide sensor 16, specifically, when an alarm informing the detection is issued by the control unit 4. For example, if the battery pack 1 is used in an electric vehicle or a stationary storage battery, the gas flow members 12-15 may be attached only when an alarm is issued by the control unit 4. This eliminates the need to attach the gas flow members 12-15 to all storage batteries, such as those for electric vehicles and stationary storage batteries, thereby further reducing the number of parts and simplifying the manufacturing process.

[0031] Furthermore, detection of whether hydrogen sulfide is being generated within the housing 11 does not have to be performed constantly. Therefore, for example, the hydrogen sulfide sensor 16 may also be detachable from the housing 11, or an on-off valve may be provided between the hydrogen sulfide sensor 16 and the housing 11. That is, to detect whether hydrogen sulfide is being generated within the housing 11 periodically or as needed, the hydrogen sulfide sensor 16 may be attached to the housing 11 each time, or the on-off valve between the hydrogen sulfide sensor 16 and the housing 11 may be opened. Note that, when two or more hydrogen sulfide sensors 16 are used as described above, one hydrogen sulfide sensor 16 may perform detection constantly, and the other hydrogen sulfide sensor 16 may perform detection only when the other hydrogen sulfide sensor 16 detects hydrogen sulfide. In this way, even if the detection result of one hydrogen sulfide sensor 16 is erroneous, the correct detection result can be obtained by the other hydrogen sulfide sensor 16. Furthermore, the control unit 4 may be physically separated from the housing 11 as shown in the figure, or may be directly attached to the housing 11, in which case it may be detachable. This also reduces the number of parts in the battery pack 1 during normal use.

[0032] On the other hand, if suppression of corrosion due to hydrogen sulfide is a priority, the air flow by the blower 14 may be performed independently of the detection of hydrogen sulfide by the hydrogen sulfide sensor 16. For example, even if hydrogen sulfide is generated at a concentration of less than 1 ppm, it is difficult to detect it with an inexpensive hydrogen sulfide sensor. However, even such a low concentration of hydrogen sulfide can corrode the materials of the battery cells 2. Therefore, regardless of the detection result of the hydrogen sulfide sensor 16, the on-off valves of the intake pipe 12 and the exhaust pipe 13 may be opened periodically or steadily, and the blower 14 may be operated to generate an air flow inside the housing 11. This allows the hydrogen sulfide concentration inside the housing 11 to be maintained low, thereby suppressing corrosion of the materials of the battery cells 2 and their accessories (such as electrode terminals and electrical circuits).

[0033] Instead of using the blower 14, a possible method for circulating gas inside the housing 11 to prevent hydrogen sulfide from accumulating inside the housing 11 is to supply a non-reactive gas, such as an inert gas, from a gas cylinder connected to the intake pipe 12. However, this method may not be able to generate a sufficient flow of gas (non-reactive gas) inside the housing 11, and may not reliably prevent an increase in the hydrogen sulfide concentration inside the housing 11. While the amount of non-reactive gas supplied may be increased to reduce the hydrogen sulfide concentration inside the housing 11, this would result in the non-reactive gas in the gas cylinder being used up prematurely, causing the hydrogen sulfide concentration to increase again. Therefore, using the blower 14 as in this embodiment is preferable because it can almost permanently prevent hydrogen sulfide generated from the battery cells 2 from accumulating inside the housing 11.

[0034] However, from another perspective, it may be preferable to supply a non-reactive gas to the inside of the casing 11. That is, if the moisture concentration inside the casing 11 is kept low by introducing a non-reactive gas, the reaction between the sulfide-based solid electrolyte contained in the battery cell 2 and moisture is suppressed, and the amount of hydrogen sulfide generated can be reduced. Even if hydrogen sulfide is generated from the battery cell 2, the risk of accelerated corrosion of the materials of the battery cell 2 and its accessory components in the coexistence of hydrogen sulfide and moisture can be reduced. Furthermore, if the oxygen concentration inside the casing 11 is kept low by introducing a non-reactive gas, the possibility of hydrogen sulfide reacting with oxygen and causing combustion can be minimized.

[0035] Therefore, in this embodiment, the air inside the housing 11 may be replaced with a non-reactive gas in advance by filling the housing 11 with a non-reactive gas while or after the battery cells 2 are housed in the housing 11. The non-reactive gas used in this case is not particularly limited as long as it does not contain moisture or oxygen that may react with the materials of the battery cells 2 and their accessories or with hydrogen sulfide. For example, the inert gases described above (nitrogen, argon, helium, etc.) may be used. As a means for supplying the non-reactive gas, for example, a filtering means may be provided in the intake pipe 12 to remove components other than the non-reactive gas (e.g., moisture, oxygen, etc.) from the air introduced into the housing 11. Examples of such filtering means include a moisture removal column, a moisture removal filter, a breathable waterproof sheet, an oxygen removal column, and a nitrogen permeable membrane.

[0036] Note that hydrogen sulfide is generated due to an abnormality in the battery cells 2. While the amount of hydrogen sulfide generated may be small in the early stages of the abnormality, it may increase rapidly over time. Therefore, hydrogen sulfide generated from the early stages of the abnormality may cause the hydrogen sulfide removal unit 15 to deteriorate. Even if a large amount of hydrogen sulfide is generated, it may not be completely removed and leak to the outside. To prepare for such a situation, or simply for backup purposes, the number of hydrogen sulfide removal units 15 is not limited to one as shown in the figure, and may be multiple. For example, as described above, if an exhaust pipe other than the exhaust pipe 13 may be connected to the housing 11, a hydrogen sulfide removal unit 15 may also be provided on the other exhaust pipe. Alternatively, if the exhaust pipe 13 branches into two downstream of the blower 14 and a hydrogen sulfide removal unit 15 may be provided on one of the two branches, a hydrogen sulfide removal unit 15 may also be provided on the other branch. As a result, for example, when the hydrogen sulfide sensor 16 detects that the hydrogen sulfide concentration inside the housing 11 has suddenly increased and exceeded the threshold value, it becomes possible to switch the air flow from the hydrogen sulfide removal unit 15 that had been in use to an unused hydrogen sulfide removal unit 15 in order to reliably remove hydrogen sulfide. On the other hand, even if hydrogen sulfide is generated due to an abnormality in the battery cell 2, the conditions inside the housing 11 (presence or absence of coexisting gases, temperature, humidity, etc.) are not always the same. For this reason, it is preferable that the multiple hydrogen sulfide removal units 15 be of different types (i.e., characteristics), which makes it possible to select and use a hydrogen sulfide removal unit 15 with optimal characteristics depending on the situation at the time.

[0037] As described above, the blower 14 may be provided in the intake pipe 12 or inside the housing 11, in addition to the illustrated exhaust pipe 13. However, the location is not limited thereto and may be, for example, on the housing 11. That is, the blower 14 may be directly attached to the exhaust port 11b of the housing 11, in which case the hydrogen sulfide removal unit 15 may be directly connected to the outlet of the blower 14. Alternatively, the blower 14 may be directly attached to the intake port 11a of the housing 11, in which case the hydrogen sulfide removal unit 15 may be directly connected to the exhaust port 11b of the housing 11. Alternatively, the blower 14 may be directly attached to the exhaust port 11b of the housing 11 via the hydrogen sulfide removal unit 15. In other words, the blower 14 may be directly attached to the outlet of the hydrogen sulfide removal unit 15, which is directly connected to the exhaust port 11b of the housing 11. Therefore, in such a case, one or both of the intake pipe 12 and the exhaust pipe 13 may be omitted from the viewpoint of reducing the number of parts.

[0038] However, providing the intake pipe 12 and the exhaust pipe 13 has the advantage that the intake position and the exhaust position relative to the housing 11 can be adjusted as desired. That is, it is possible to select the optimal intake position and the exhaust position according to the surrounding environment in which the battery pack 1 is installed. For example, by setting the intake position at a position that minimizes the intake of air containing a large amount of moisture and foreign matter, the risk of the battery pack 1 malfunctioning can be reduced. Furthermore, by positioning the exhaust position as far away as possible from other devices and people in the vicinity, the risk of the exhausted air adversely affecting them can be reduced. Thus, providing the intake pipe 12 and the exhaust pipe 13 is preferable in that it can reduce the risk of the battery pack 1 malfunctioning and the risk of adversely affecting the surrounding environment.

[0039] Second Embodiment Fig. 2 is a schematic diagram of a battery pack according to a second embodiment of the present invention. This embodiment is a modification of the first embodiment, and differs from the first embodiment in that several additional components are provided. The following description will focus on the differences from the first embodiment.

[0040] As described above, even if the flammable hydrogen sulfide gas is generated inside the housing 11, combustion of the hydrogen sulfide will not occur unless its concentration reaches the flammable range. On the other hand, regardless of the hydrogen sulfide concentration, combustion of the hydrogen sulfide will not occur unless the oxygen concentration inside the housing 11 exceeds the limit oxygen concentration of hydrogen sulfide. Therefore, in this embodiment, the intake pipe 12 is provided with an oxygen remover 21 that removes oxygen from the air flowing into the housing 11. This, in addition to the oxygen inside the housing 11 being discharged to the outside by the action of the blower 14, can reduce the oxygen concentration inside the housing 11. The oxygen remover 21 is not particularly limited, and any known oxygen remover commonly used for removing oxygen can be used. Examples of such removers include metal-based oxygen adsorbents containing iron, copper, nickel, etc., and organic oxygen adsorbents containing vitamin C, etc.

[0041] For the reasons described above, in this embodiment, it is preferable to monitor the oxygen concentration within the housing 11. To this end, the battery pack 1 preferably includes an oxygen sensor 22 that detects the oxygen concentration within the housing 11. In this case, the control unit 4 may control the output of the blower 14 based on the detection result of the oxygen sensor 22. That is, the output of the blower 14 may be controlled to adjust the flow rate of air (specifically, oxygen-removed air) flowing into the housing 11 so that the oxygen concentration detected by the oxygen sensor 22 is less than the limiting oxygen concentration of hydrogen sulfide. Furthermore, the output of the battery cells 2 may be controlled based on the detection result of the oxygen sensor 22. For example, if the oxygen concentration detected by the oxygen sensor 22 is equal to or greater than the limiting oxygen concentration of hydrogen sulfide or there is a possibility of this (e.g., if the oxygen concentration is equal to or greater than an arbitrarily set predetermined value below the limiting oxygen concentration), the output of at least some of the battery cells 2 may be limited or stopped for safety reasons. Furthermore, the detection result of the oxygen sensor 22 may be stored in the control unit 4 for immediate or future use, or may be transmitted to a server or a blockchain network via the control unit 4.

[0042] The oxygen sensor 22 is not particularly limited, and may be any known oxygen sensor such as a zirconia type, an electrochemical type, a magnetic type, an optical type, a laser spectroscopy type, or a yellow phosphorus luminescence type. The position of the oxygen sensor 22 is not limited to the position shown in the figure, as long as it can detect the oxygen concentration inside the housing 11. For example, the oxygen sensor 22 may be located on the intake pipe 12 (specifically, downstream of the oxygen remover 21) or on the exhaust pipe 13.

[0043] The problem of hydrogen sulfide remaining in the casing 11 would not occur if hydrogen sulfide were not generated in the first place. To suppress this generation, it is preferable to lower the temperature inside the casing 11. However, an excessively low temperature inside the casing 11 is undesirable because it may degrade the performance of the battery cells 2. Therefore, the battery pack 1 may include a temperature sensor 23 that detects the temperature inside the casing 11 and a temperature adjustment unit 24 that is controlled by the control unit 4 based on the detection result of the temperature sensor 23 and adjusts the temperature of the air flowing into the casing 11. This prevents the temperature inside the casing 11 from increasing and generating hydrogen sulfide even when the battery cells 2 generate heat, and prevents the performance of the battery cells 2 from deteriorating as the temperature inside the casing 11 decreases even when the outside air temperature decreases. Furthermore, the output of at least some of the battery cells 2 may be adjusted based on the detection result of the temperature sensor 23. For example, the output of at least some of the battery cells 2 may be limited or stopped when the temperature detected by the temperature sensor 23 falls outside a predetermined range.

[0044] The temperature sensor 23 is not particularly limited, and can be, for example, a known temperature sensor, such as a contact or non-contact type. Examples of contact temperature sensors include thermocouples, resistance temperature detectors, and thermistors. Examples of non-contact temperature sensors include radiation thermometers. The location of the temperature sensor 23 is not limited to the location shown in the figure, as long as it can detect the temperature inside the housing 11. In the example shown, only one temperature sensor 23 is installed in the housing 11, but multiple temperature sensors 23 may be installed. In this case, a temperature sensor 23 may be installed near each battery cell 2. The detection results of the temperature sensor 23 may be stored in the control unit 4 for immediate or future use, or transmitted to a server or a blockchain network via the control unit 4. The temperature adjustment unit 24 is not particularly limited, and can be, for example, a combination of a known cooling device, such as an air-cooled, water-cooled, or refrigerant-type device, and a known heating device, such as an electric heating device or a heat pump-type device. The location of the temperature adjustment unit 24 is not limited to the location shown in the figure, as long as it can adjust the temperature of the battery cell 2. For example, the temperature adjustment unit 24 may be provided inside the housing 11 to directly adjust the temperature of the battery cell 2, or may be provided outside the housing 11 to indirectly adjust the temperature of the battery cell 2 via the housing 11.

[0045] The oxygen remover 21 and the temperature adjuster 24 may be detachable from the housing 11 together with the intake pipe 12. Similarly to the hydrogen sulfide sensor 16, the oxygen sensor 22 and the temperature sensor 23 may also be detachable from the housing 11.

[0046] It is preferable that the hydrogen sulfide removal unit 15 is replaced with a new one periodically or according to the usage conditions, and when a predetermined replacement time arrives or replacement becomes necessary, a notification to notify the user is preferably output from the control unit 4. In this case, when the battery pack 1 is used in an electric vehicle or a stationary storage battery, for example, the notification is preferably converted into a signal that appeals to the user's five senses, such as sight and hearing, and then output.

[0047] Furthermore, when replacing the hydrogen sulfide removal unit 15, it is preferable that the hydrogen sulfide removal unit 15 be provided with an identifier 25 containing its own identification information so that it can be confirmed whether the replaced hydrogen sulfide removal unit 15 satisfies predetermined usage conditions, such as being genuine and having not expired. The identifier 25 may be, for example, an information storage medium such as a wireless tag or a code such as a one-dimensional code or a two-dimensional code, but is preferably a code, and more preferably a two-dimensional code such as a QR Code (registered trademark). Accordingly, the control unit 4 is preferably equipped with a function for communicating with a reader (not shown) that reads the identification information from the identifier 25 and acquiring the read results, and information necessary for identifying a genuine product is preferably recorded therein. This allows the control unit 4 to determine whether the hydrogen sulfide removal unit 15 satisfies predetermined usage conditions based on the acquired identification information. If the control unit 4 determines that the replaced hydrogen sulfide removal unit 15 does not satisfy the predetermined usage conditions, it can notify the user of this and disable output from at least some of the battery cells 2. The control unit 4 may transmit the acquired identification information of the hydrogen sulfide removal unit 15, the determination result thereof, the usage status of the hydrogen sulfide removal unit 15, etc. to a server or a blockchain network. Also, the reading result of the identifier 25 by the reading device may be transmitted to a server or a blockchain network instead of to the control unit 4, where the above-mentioned determination is made, and the determination result may be transmitted to the control unit 4.

[0048] The control unit 4 preferably has a function of directly acquiring the usage status (e.g., usage time) of all devices that are communication targets (e.g., the air blower 14, sensors 16, 22, 23, etc.) and, thereby, indirectly acquiring the usage status of devices that are not communication targets (e.g., the hydrogen sulfide removal unit 15, the oxygen removal unit 21, etc.). Furthermore, the control unit 4 may have a function of predicting the lifespan of the hydrogen sulfide removal unit 15 based on the acquired usage status in order to appropriately determine when the hydrogen sulfide removal unit 15 needs to be replaced (its lifespan). Alternatively, in addition to this, the control unit 4 may have a function of transmitting the acquired usage status to a server or a blockchain network to enable an external management device to predict the lifespan of the hydrogen sulfide removal unit 15. The acquired usage status and the lifespan prediction results are preferably notified to the user by the control unit 4 or the external management device as needed, thereby enabling planned replacement of the hydrogen sulfide removal unit 15 in accordance with the lifespan prediction. As a result, it is possible to reduce the possibility of increased maintenance costs due to early replacement when unnecessary, or the possibility of serious malfunctions due to not replacing the hydrogen sulfide removal unit 15 when necessary. Furthermore, such a lifespan prediction is advantageous in that it eliminates the need to carry out inspection work to determine when to replace the hydrogen sulfide removal unit 15, thereby reducing inspection costs, including labor costs. A program or artificial intelligence (AI) can be used to predict the lifespan of the hydrogen sulfide removal unit 15, but from the viewpoint of prediction accuracy, it is preferable to use AI.

[0049] The timing at which the control unit 4 acquires and transmits data regarding the usage status of each device is not particularly limited. For example, the acquisition and transmission may be periodic, automatic according to predetermined conditions, or irregular, such as by remote control from an external device. This allows for more accurate understanding of the usage status of each device. However, if similar data transmission is also performed from multiple other battery packs, it is preferable that the control unit 4 transmits data at a different timing from those other battery packs. This allows for reliable data transmission without congesting communication lines or servers. It is preferable that the control unit 4 be powered by a power source independent of the battery cells 2 so that data transmission can be reliably performed even if the output of the battery cells 2 must be stopped.

[0050] The above-described lifespan prediction enables planned replacement of the hydrogen sulfide removal unit 15. However, depending on the usage environment (region) of the battery pack 1 and the manufacturing status of the hydrogen sulfide removal unit 15, new or unused hydrogen sulfide removal units 15 may not be available at the time when the end of the battery pack's life is predicted. In other words, if demand for hydrogen sulfide removal units 15 is concentrated in a particular region and a supply shortage occurs as a result, new or unused hydrogen sulfide removal units 15 may not be available in a planned manner. To avoid this, the control unit 4 preferably has a function for acquiring location information and a function for transmitting the location information, along with the usage status of each device, to a server or a blockchain network. This allows an external management device to predict in advance the number and timing of hydrogen sulfide removal units 15 required in each region, and based on this, it is possible to secure an optimal number of hydrogen sulfide removal units 15 in stock for each region. Furthermore, the external management device may notify the user of the optimal source for purchasing hydrogen sulfide removal units 15. As a result, hydrogen sulfide removal units 15 can be obtained when and where they are needed, enabling planned replacement of hydrogen sulfide removal units 15.

[0051] The above description regarding the lifespan prediction of the hydrogen sulfide removal unit 15 applies to all communication target devices whose usage status is directly acquired by the control unit 4, as well as other devices whose usage status is indirectly acquired (such as the oxygen removal unit 21). After replacing components, including the hydrogen sulfide removal unit 15, it is preferable to collect the replaced components and analyze their deterioration status, thereby improving the accuracy of the lifespan prediction for each component. Taking the hydrogen sulfide removal unit 15 as an example, collecting and analyzing it can determine the amount of hydrogen sulfide generated during use. Then, by comparing this amount with previously acquired usage status, data can be obtained regarding the conditions and frequency of abnormalities in the battery cell 2. Based on the obtained data, the accuracy of the lifespan prediction for the hydrogen sulfide removal unit 15 can be improved. Such data can also be used to anticipate potential problems when commercializing new types of batteries.

[0052] (Third embodiment) Fig. 3 is a schematic diagram of a battery pack according to a third embodiment of the present invention. This embodiment is a modification of the first embodiment, and differs from the first embodiment in that the configurations of the intake piping and the exhaust piping are changed. The following description will focus on the differences from the first embodiment.

[0053] In the first embodiment, the upstream end (the other end) of the intake pipe 12 and the downstream end (the other end) of the exhaust pipe 13 are both open to the outside, whereas in the present embodiment, they are connected to each other to form a circulation pipe 31 that circulates the air inside the housing 11 without discharging it to the outside. This makes it possible to prevent the battery cells 2 from coming into contact with outside air containing moisture, thereby reducing the possibility of generating hydrogen sulfide, compared to the first embodiment. Furthermore, in the present embodiment, it is possible to prevent hydrogen sulfide from leaking to the outside even if the above-mentioned removing agent serving as the hydrogen sulfide removal unit 15 breaks through. As a result, compared to the first embodiment, it is possible to reduce the hydrogen sulfide concentration inside the housing 11 while reliably preventing hydrogen sulfide from leaking to the outside.

[0054] In this embodiment, the circulation pipe 31 forms a closed circuit, which virtually eliminates the possibility of contact between the battery cells 2 and the outside air as described above. However, there is a concern that the internal pressure of the casing 11 may increase or decrease in some cases. An increase in internal pressure may occur, for example, when the temperature inside the casing 11 increases due to heat generation from the battery cells 2 or an increase in the outside air temperature, or when gases such as hydrogen sulfide are generated from the battery cells 2. A decrease in internal pressure may occur, for example, when the temperature inside the casing 11 decreases due to a decrease in the outside air temperature. Therefore, the battery pack 1 preferably includes a pressure sensor 32 that detects the pressure inside the casing 11 and a pressure adjustment unit 33 that is controlled by the control unit 4 based on the detection result of the pressure sensor 32 and adjusts the pressure inside the casing 11. This makes it possible to prevent excessive increases or decreases in the internal pressure of the casing 11. Furthermore, the output of at least some of the battery cells 2 may be adjusted based on the detection result of the pressure sensor 32. For example, the output of at least some of the battery cells 2 may be limited or stopped when the pressure detected by the pressure sensor 32 falls outside a predetermined range.

[0055] The pressure sensor 32 is not particularly limited, and any known pressure sensor such as a resistive film type, a capacitance type, a piezoelectric element type, a photoelectric type, or a MEMS (MicroElectroMechanical Systems) type can be used. The position of the pressure sensor 32 is not limited to the position shown in the figure, as long as it can detect the pressure inside the housing 11. The detection result of the pressure sensor 32 may be stored in the control unit 4 for immediate or future use, or may be transmitted to a server or a blockchain network via the control unit 4.

[0056] The pressure regulator 33 is not particularly limited and may be, for example, an electric valve, a solenoid valve, a relief valve, a compressor, a gas cylinder, an accumulator, or the like. Pressure regulators 33 include those that release the internal pressure of the housing 11 and those that pressurize the housing 11. These two types (e.g., an electric valve and a compressor) may be combined or integrated. This allows the pressure inside the housing 11 to be adjusted appropriately depending on the situation. When using a pressure regulator 33 that combines the above-mentioned two types, it is preferable that it has the function of allowing air to flow into and out of the housing 11 while preventing the intrusion of foreign matter and moisture from the outside, thereby eliminating the pressure difference between the inside and outside of the housing 11. This also reduces the possibility of damage to the housing 11 due to the pressure difference between the inside and outside of the housing 11. Examples of such pressure regulators 33 include an air filter, a moisture-removing filter, and a breathable waterproof sheet.

[0057] The location of the pressure adjustment unit 33 is not limited to the location shown in the figure. However, in the case of a pressure adjustment unit 33 having the function of releasing the internal pressure of the housing 11 (including a combination of the two types described above), it is preferably located downstream of the hydrogen sulfide removal unit 15 in the circulation pipe 31. Alternatively, the pressure adjustment unit 33 may be provided directly in the container of the hydrogen sulfide removal unit 15. In this case, it is preferably located downstream of the hydrogen sulfide remover in the direction of air flow within the container. This reduces the possibility of hydrogen sulfide leaking to the outside. However, to prevent hydrogen sulfide-containing gas from being discharged to the outside of the housing 11 without passing through the hydrogen sulfide removal unit 15, it is preferable to close the on-off valve located on the air intake 11a side of the circulation pipe 31 when the pressure adjustment unit 33 releases the internal pressure of the housing 11. Even when the pressure adjustment unit 33 is provided in the housing 11 as shown in the figure, a hydrogen sulfide removal unit similar to the hydrogen sulfide removal unit 15 is preferably provided at the pressure outlet of the pressure adjustment unit 33 to prevent hydrogen sulfide from leaking to the outside when pressure is released. On the other hand, a pressure adjustment unit 33 that pressurizes the housing 11 is preferably provided in the housing 11. This allows, for example, when hydrogen sulfide is generated from the battery cell 2, to increase the pressure inside the housing 11 and reduce the amount of hydrogen sulfide released from the battery cell 2. Furthermore, to increase the pressure inside the housing 11 and thereby further reduce the amount of hydrogen sulfide released from the battery cell 2, outside air may be introduced into the housing 11 via the pressure adjustment unit 33. In this case, the pressure adjustment unit 33 is preferably provided with a filtering unit that removes components (e.g., moisture, oxygen, etc.) contained in the outside air other than non-reactive gases. Examples of such filtering units include a moisture removal column, a moisture removal filter, a breathable waterproof sheet, an oxygen removal column, and a nitrogen permeable membrane. The number of pressure adjusting units 33 is not limited to one as shown in the figure, and may be plural.

[0058] The circulation pipe 31 is preferably unitized as a gas flow unit together with the air blower 14 and the hydrogen sulfide removal unit 15. This allows the circulation pipe 31, including the air blower 14 and the hydrogen sulfide removal unit 15, to be handled as a single component when assembling the battery pack 1, thereby reducing the number of components and simplifying the manufacturing process. Furthermore, the gas flow units 14, 15, and 31 may be detachably attached to the housing 11, similar to the gas flow members 12 to 15 of the first embodiment, and the pressure adjustment unit 33 may also be detachably attached to the housing 11. Furthermore, the pressure sensor 32 may also be detachable from the housing 11, similar to the hydrogen sulfide sensor 16.

[0059] Needless to say, the configurations described in the second embodiment can also be applied to this embodiment. In this case, the oxygen remover 21 and the temperature adjuster 24 may be provided in a position of the circulation pipe 31 corresponding to the exhaust pipe 13 (specifically, upstream of the hydrogen sulfide remover 15), rather than in a position of the circulation pipe 31 corresponding to the intake pipe 12 (specifically, downstream of the hydrogen sulfide remover 15). The oxygen remover 21 may be structurally and functionally integrated with the hydrogen sulfide remover 15, thereby reducing the number of parts and facilitating replacement due to deterioration. The oxygen remover 21 and the hydrogen sulfide remover 15 may be arranged in parallel, or in a combination of series and parallel. That is, for example, a bypass pipe bypassing the hydrogen sulfide remover 15 may be provided in the circulation pipe 31, and the oxygen remover 21 may be provided in the bypass pipe. This allows air to flow only through the hydrogen sulfide removal unit 15 when removing only hydrogen sulfide, and only through the oxygen removal unit 21 when removing only oxygen, enabling response according to the state of the battery cell 2. Alternatively, a bypass pipe that bypasses the serially arranged hydrogen sulfide removal unit 15 and oxygen removal unit 21 may be provided in the circulation pipe 31, and the hydrogen sulfide removal unit 15 may be provided in the bypass pipe. In addition, in this embodiment, when the oxygen removal unit 21 removes oxygen from the housing 11, the volume of air within the housing 11 decreases, which may result in a decrease in pressure within the housing 11. Therefore, when the oxygen removal unit 21 is applied to this embodiment, it is preferable to use a pressure adjustment unit 33 that pressurizes the housing 11, thereby adjusting the pressure within the housing 11 to an appropriate pressure. That is, the pressure within the housing 11 can be adjusted to an appropriate pressure by compensating for the reduced air volume using, for example, a compressor or a gas cylinder filled with an inert gas.

[0060] (Fourth embodiment) Fig. 4 is a schematic diagram of a battery pack according to a fourth embodiment of the present invention. This embodiment is a modification of the third embodiment, and differs from the third embodiment in that the circulation piping is omitted. The following description will focus on the differences from the third embodiment.

[0061] In this embodiment, the circulation piping 31 of the third embodiment is omitted. Accordingly, the blower 14 is provided inside the housing 11, and the hydrogen sulfide removal unit 15 is provided on the housing 11. Specifically, the blower 14 is provided at the exhaust port 11b inside the housing 11, and the hydrogen sulfide removal unit 15 is provided on the housing 11 so that its inlet and outlet are directly connected to the exhaust port 11b and the intake port 11a of the housing 11, respectively. This allows the air inside the housing 11 to be circulated without being discharged to the outside, even without a circulation piping, thereby achieving the same effect as in the third embodiment. Here, "directly connected" means, for example, that the inlet of the hydrogen sulfide removal unit 15 and the exhaust port 11b of the housing 11 are connected to each other without a piping, and also includes the case where they are connected to each other via the blower 14. Therefore, in this embodiment, the location of the blower 14 is not limited to inside the housing 11 and may be on the housing 11. That is, the blower 14 may be directly attached to the exhaust port 11b outside the housing 11. Alternatively, the blower 14 may be directly attached to the intake port 11a outside the housing 11, in which case the outlet of the hydrogen sulfide removal unit 15 and the intake port 11a of the housing 11 may be in communication with each other via the blower 14. Needless to say, the position of the blower 14 within the housing 11 is not particularly limited.

[0062] Fifth Embodiment Fig. 5 is a schematic diagram of a battery pack according to a fifth embodiment of the present invention. This embodiment is a modification of the first embodiment, and differs from the first embodiment in that the configuration of the housing has been changed, and the configurations of the intake and exhaust pipes have been changed accordingly. The following description will focus on the differences from the first embodiment.

[0063] In this embodiment, the housing 11 includes multiple storage chambers 41, each housing a battery cell 2. Accordingly, the downstream end of the intake pipe 12 branches into multiple sections, each connected to the multiple storage chambers 41 (specifically, the intake ports 41 a) via an on-off valve (not shown). The upstream end of the exhaust pipe 13 also branches into multiple sections, each connected to the multiple storage chambers 41 (specifically, the exhaust ports 41 b) via an on-off valve (not shown). While FIG. 4 shows four storage chambers 41, the number of storage chambers 41 constituting the housing 11 is not limited to this. Furthermore, the number of battery cells 2 housed in each storage chamber 41 is not limited to one, as shown, and may be multiple, and these may form a battery module (battery pack). Additionally, the hydrogen sulfide sensor 16 is provided downstream of the portion of the exhaust pipe 13 where the multiple branch pipes converge. Furthermore, the control unit 4 periodically or as needed executes an abnormality determination process to determine which of the multiple storage chambers 41 is generating hydrogen sulfide.

[0064] In the abnormality determination process, the air blower 14 operates as the on-off valves of the intake pipe 12 and the exhaust pipe 13 are sequentially opened. This sequentially generates air flows from each storage chamber 41 to the hydrogen sulfide sensor 16, and the presence of hydrogen sulfide in each storage chamber 41 is sequentially detected by the hydrogen sulfide sensor 16. This detection method is advantageous in that it can forcibly introduce air from each storage chamber 41 into the hydrogen sulfide sensor 16, making it possible to detect even a slight amount of hydrogen sulfide generation without overlooking it. Then, based on the detection results obtained in this manner, it is determined in which of the multiple storage chambers 41 hydrogen sulfide is being generated.

[0065] When it is confirmed that hydrogen sulfide has been generated in a specific storage chamber 41, the control unit 4 opens the on-off valves of the intake pipe 12 and the exhaust pipe 13 connected to that storage chamber 41 and activates the air blower 14. This generates an air flow only within the storage chamber 41 where hydrogen sulfide generation has been confirmed, making it possible to more efficiently prevent hydrogen sulfide from accumulating and leaking to the outside. The control unit 4 may also limit or stop the output of the battery cells 2 in the storage chamber 41 where hydrogen sulfide generation has been confirmed, thereby minimizing the impact on the output of the entire battery pack 1.

[0066] If cost and design constraints permit, a hydrogen sulfide sensor 16 may be provided for each storage chamber 41. Although not shown, a temperature sensor 23 may be provided for each storage chamber 41, and based on the results of the temperature sensor 23, the output of the battery cell 2 in the storage chamber 41 in which an excessive temperature rise is detected may be limited or stopped. As in the second embodiment, an oxygen remover 21 may be provided in the intake pipe 12, and a circulation pipe may be configured by connecting the upstream end of the intake pipe 12 and the downstream end of the exhaust pipe 13, as in the third embodiment.

[0067] REFERENCE SIGNS LIST 1 battery pack 2 battery cell 3 battery containing body 4 control unit 11 housing 11a intake port 11b exhaust port 12 intake pipe 13 exhaust pipe 14 blower unit 15 hydrogen sulfide removal unit (active gas removal unit) 16 hydrogen sulfide sensor (gas sensor) 21 oxygen removal unit 22 oxygen sensor 23 temperature sensor 24 temperature adjustment unit 25 identifier 31 circulation pipe 32 pressure sensor 33 pressure adjustment unit 41 accommodation chamber 41a intake port 41b exhaust port

Claims

1. A battery container having a housing having an air intake port and an exhaust port and housing at least one battery cell; a blower section that generates an air flow from the air intake port toward the exhaust port inside the housing; and an active gas removal section that removes active gas generated from the at least one battery cell and discharged from the exhaust port by the air flow.

2. The battery container according to claim 1, comprising an intake pipe having one end connected to the intake port, and an exhaust pipe having one end connected to the exhaust port, wherein the blower is provided inside the housing, in the intake pipe, or in the exhaust pipe, and the active gas removal unit is provided in the exhaust pipe.

3. The battery containing body according to claim 2, further comprising a circulation pipe for circulating air within the housing, the circulation pipe being made up of the intake pipe and the exhaust pipe whose other end is connected to the intake pipe.

4. The battery container according to claim 1, wherein the active gas removal section is provided on the housing and has an inlet and an outlet that directly communicate with the exhaust port and the intake port, respectively, to circulate air within the housing.

5. The battery container according to any one of claims 1 to 4, further comprising a control unit that controls the air blowing unit.

6. A battery container as described in claim 5, further comprising a gas sensor that detects the presence or concentration of the active gas in the housing, and wherein the control unit operates the blower to generate the air flow when the active gas is detected by the gas sensor.

7. The battery containing body according to claim 5, further comprising: a pressure sensor that detects the pressure inside the housing; and a pressure adjustment section that is controlled by the control section based on the detection result of the pressure sensor and adjusts the pressure inside the housing.

8. The battery container according to any one of claims 1 to 4, wherein the active gas is a flammable gas.

9. The battery container described in claim 8, further comprising: a gas sensor that detects the presence or concentration of the active gas in the housing; and a control unit that controls the blower to adjust the flow rate of the air flowing into the housing so that the concentration of the combustible gas detected by the gas sensor is below a lower flammable limit value.

10. The battery container according to claim 8, further comprising an oxygen removing section that removes oxygen from the air that flows into the housing through the air intake.

11. The battery container described in claim 10, further comprising: an oxygen sensor that detects an oxygen concentration within the housing; and a control unit that controls the blower to adjust the flow rate of the air flowing into the housing so that the oxygen concentration detected by the oxygen sensor is less than the limit oxygen concentration of the combustible gas.

12. The battery container described in claim 5, wherein the active gas removal unit is assigned an identifier including identification information of the active gas removal unit, and the control unit determines whether the active gas removal unit satisfies predetermined conditions based on the identification information read from the identifier.

13. The battery containing body according to claim 5, further comprising: a temperature sensor that detects the temperature inside the housing; and a temperature adjustment unit that is controlled by the control unit based on the detection result of the temperature sensor and adjusts the temperature inside the housing.

14. The battery containing body according to claim 5, wherein the control unit predicts the life of the active gas removal unit based on at least a usage status of the air blowing unit.

15. The battery container according to claim 5, wherein the control unit acquires location information and transmits the acquired location information and at least the usage status of the blower unit to the outside.

16. The battery containing body according to claim 2 or 3, wherein the intake pipe, the exhaust pipe, the blower and the active gas removal unit are detachably attached to the housing.

17. A battery container as described in claim 2 or 3, wherein the housing has a plurality of storage chambers each for accommodating a battery cell, and the one ends of the intake pipe and the exhaust pipe each branch into a plurality of pipes and are connected to the plurality of storage chambers.

18. The battery container according to claim 17, comprising: at least one gas sensor that detects the presence of the active gas in the plurality of storage chambers; and a control unit that switches which of the plurality of storage chambers is to generate the air flow in based on a detection result of the at least one gas sensor.

19. A battery pack comprising: at least one battery cell; a battery container according to any one of claims 1 to 4; and a control unit that controls the at least one battery cell.

20. The battery pack of claim 19, wherein the battery container has a gas sensor that detects the presence of the active gas in the housing, and the control unit limits or stops the output of the at least one battery cell when the active gas is detected by the gas sensor.

21. A battery pack as described in claim 19, wherein the battery container has at least one of a temperature sensor that detects the temperature inside the housing and an oxygen sensor that detects the oxygen concentration inside the housing, and the control unit adjusts the output of the at least one battery cell based on the detection result of at least one of the temperature sensor and the oxygen sensor.

22. A battery pack as described in claim 19, wherein the active gas removal unit is assigned an identifier including identification information of the active gas removal unit, and the control unit determines whether or not the active gas removal unit satisfies a specified condition based on the identification information read from the identifier, and does not output the at least one battery cell if it determines that the active gas removal unit does not satisfy the specified condition.

23. A battery pack as described in claim 19, wherein the battery housing comprises an intake pipe having one end connected to the intake port and an exhaust pipe having one end connected to the exhaust port and the other end connected to the intake pipe, a circulation pipe for circulating air within the housing, and a pressure sensor for detecting pressure within the housing, and the control unit adjusts the output of the at least one battery based on the detection result of the pressure sensor.

24. A battery pack comprising: a plurality of battery cells; a battery container according to claim 17; and a control unit that controls the plurality of battery cells.

25. A battery pack as described in claim 24, wherein the battery container has at least one gas sensor that detects the presence of the active gas in the plurality of container chambers, and the control unit switches between limiting or stopping the output of one of the plurality of battery cells based on the detection result of the at least one gas sensor.

26. A gas circulation unit that circulates gas inside a housing that contains at least one battery cell, the gas circulation unit having: a circulation pipe that is connected to the housing at both ends and circulates air inside the housing; a blower section that is provided in the circulation pipe and generates an air flow inside the housing; and an active gas removal section that is provided in the circulation pipe and removes active gas that is generated from the at least one battery cell and circulates through the circulation pipe.

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