Battery accommodation body, battery module, and battery pack

Abstract

A battery accommodation body 1 includes: a housing 3 which accommodates battery cells 2; an active gas removal part 4 which is provided in the housing 3 and removes active gas generated from the battery cells 2; and a blower part 5 which is provided in the housing 3 and circulates a gaseous body in the housing 3 while distributing the gaseous body to the active gas removal part 4.

Description

Battery housing, battery module, and battery pack

[0001] The present invention relates to a battery containing body, a battery module, 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 effects 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). These problems may also occur when other active gases besides hydrogen sulfide are generated, and may also occur when various other active gases are generated in batteries other than all-solid-state batteries containing sulfide-based solid electrolytes. Therefore, there is a need for a solution that can be applied to such a wide variety of active gases.

[0005] Therefore, an object of the present invention is to provide a battery container, a battery module, and a battery pack that suppress the leakage of active gas generated inside to the outside and also suppress an increase in the concentration of the active gas.

[0006] In order to achieve the above-mentioned object, the battery containing body of the present invention has a housing that contains battery cells, an active gas removal section provided within the housing that removes active gas generated from the battery cells, and an air blowing section provided within the housing that circulates the gas within the housing while circulating it through the active gas removal section.

[0007] A battery module of the present invention includes the battery containing body and battery cells contained in the housing of the battery containing body.

[0008] A battery pack of the present invention includes the battery module and a control unit that controls the battery module.

[0009] With such a battery containing body, battery module, and battery pack, even if active gas is generated from a battery cell, the gas inside the housing containing the active gas can be circulated while being forcibly introduced into the active gas removal section, thereby suppressing an increase in the concentration of the active gas inside the housing and reducing the possibility that the active gas will have an adverse effect inside the housing.

[0010] As described above, according to the present invention, it is possible to prevent active gas generated inside the battery containing body, the battery module, and the battery pack from leaking to the outside, and it is also possible to prevent an increase in the concentration of the active gas.

[0011] 1 is a schematic configuration diagram of a battery module according to a first embodiment of the present invention; 2 is a schematic configuration diagram of a battery module according to a second embodiment of the present invention; 3 is a schematic configuration diagram of a battery module according to a third embodiment of the present invention; and 4 is a schematic configuration diagram of a battery module according to a fourth embodiment of the present invention.

[0012] 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.

[0013] 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.

[0014] First Embodiment FIG. 1 is a schematic diagram of a battery module according to a first embodiment of the present invention.

[0015] The battery module 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 in series, parallel, or a combination of these. At least some 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 eight battery cells 2, the number of battery cells 2 included in the battery module 1 is not limited to this. A battery pack is formed by combining a plurality of battery modules 1 and housing them in a case.

[0016] 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.

[0017] 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.

[0018] 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.

[0019] 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.

[0020] The battery module 1 also has a housing 3, a hydrogen sulfide removal section (active gas removal section), and a blower section 5, which together form a battery housing that accommodates a plurality of battery cells 2.

[0021] The housing 3 is configured to hermetically house multiple battery cells 2 while extending at least one pair of electrode terminals (not shown) to the outside. Fillers such as elastic materials, heat transfer materials, and heat insulating materials may be appropriately disposed inside the housing 3 in gaps between the battery cells 2 or between the battery cells 2 and the restraining members described above. While the housing 3 is shown in a simplified form in FIG. 1 , considering heat dissipation from the battery cells 2, it is preferable that at least a portion of the multiple battery cells 2 be housed in the housing 3 in direct or indirect contact with the housing 3 (for example, via the restraining members described above). The shape of the housing 3 is not particularly limited and can be set as desired depending on the shape and arrangement of the battery cells 2 to be housed.

[0022] The hydrogen sulfide removal unit 4 is provided within the housing 3 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 4 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 makes it possible to reliably remove hydrogen sulfide even at high temperatures, and also to suppress the re-release of the removed hydrogen sulfide.

[0023] The blower 5 is provided at the inlet 4a of the hydrogen sulfide removal unit 4 and has the function of circulating the air (gas) inside the housing 3 while passing it through the hydrogen sulfide removal unit 4. The blower 5 is not particularly limited, and may be, for example, a fan, blower, pump, compressor, or the like. In this case, the blower 5 may be configured with variable output, thereby adjusting the flow rate of air circulating inside the housing 3. Note that power may be supplied to the blower 5 from the battery cell 2 to drive the blower 5. Alternatively, a separate, independent power source may be provided, which allows the blower 5 to be reliably driven even in a situation where the output of the battery cell 2 must be limited or stopped.

[0024] With this configuration, even if hydrogen sulfide is generated from the battery cells 2, the air containing the hydrogen sulfide within the casing 3 can be forcibly introduced into the hydrogen sulfide removal unit 4 and circulated, thereby preventing an increase in the hydrogen sulfide concentration within the casing 3. As a result, the possibility of hydrogen sulfide, as a flammable gas, reacting with oxygen within the casing 3 and burning, or hydrogen sulfide, as a corrosive gas, corroding the materials of the battery cells 2, can be reduced. Furthermore, because the casing 3 is sealed, the battery cells 2 are prevented from coming into contact with outside air containing moisture, thereby reducing the possibility of generating hydrogen sulfide. In addition, even if the removal agent serving as the hydrogen sulfide removal unit 4 breaks through, leakage of hydrogen sulfide to the outside can be prevented.

[0025] To prevent hydrogen sulfide generation, the casing 3 may be filled in advance with a gas other than air, such as a non-reactive gas such as an inert gas. This reduces the moisture concentration within the casing 3, thereby suppressing the reaction between the sulfide-based solid electrolyte contained in the battery cell 2 and moisture, thereby reducing the amount of hydrogen sulfide generated. Even if hydrogen sulfide is generated from the battery cell 2, the coexistence of hydrogen sulfide and moisture can reduce the risk of accelerated corrosion of the materials of the battery cell 2 and its accessories (such as electrode terminals and electrical circuits). Furthermore, filling the casing 3 with a non-reactive gas reduces the oxygen concentration within the casing 3, thereby minimizing the possibility of hydrogen sulfide reacting with oxygen and resulting in combustion. The non-reactive gas used in this case is not particularly limited as long as it does not contain moisture or oxygen that could react with the materials of the battery cell 2 and its accessories or hydrogen sulfide. For example, the inert gases described above (such as nitrogen, argon, and helium) can be used.

[0026] In the illustrated example, the blower 5 is provided at the inlet 4a of the hydrogen sulfide removal unit 4, but it may also be provided, for example, at the outlet 4b of the hydrogen sulfide removal unit 4 or inside thereof. Alternatively, the blower 5 may be provided at a position away from the hydrogen sulfide removal unit 4. In other words, the position of the blower 5 is not particularly limited as long as it is located within the housing 3, including the interior of the hydrogen sulfide removal unit 4, and as long as it can circulate air within the housing 3 to the hydrogen sulfide removal unit 4. Furthermore, the number of hydrogen sulfide removal units 4 is not limited to one as shown in the figure, and may be multiple, and accordingly, the number of blowers 5 may also be multiple.

[0027] Second Embodiment Fig. 2 is a schematic diagram of a battery module 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 the operation of the air blower is controllable. The following description will focus on the differences from the first embodiment.

[0028] Air circulation within the housing 3 may be performed continuously, i.e., the blower 5 may be operating continuously, but from the viewpoint of reducing power consumption, it is preferable that the blower 5 is normally stopped. Furthermore, it is preferable that the blower 5 be activated in response to the generation of hydrogen sulfide from the battery cells 2, i.e., it is preferable that air circulation within the housing 3 be started. For this purpose, the battery module 1 of this embodiment has a hydrogen sulfide sensor (gas sensor) 11 and a control unit 21.

[0029] The hydrogen sulfide sensor 11 has a function of detecting the presence or concentration of hydrogen sulfide within the housing 3. The type of hydrogen sulfide sensor 11 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 11 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 3. In the example shown in the figure, only one hydrogen sulfide sensor 11 is installed in the housing 3, but multiple hydrogen sulfide sensors 11 may be installed. In this case, a hydrogen sulfide sensor 11 may be installed near each battery cell 2. One of the multiple hydrogen sulfide sensors 11 may be installed near the outlet 4b of the hydrogen sulfide removal unit 4 to detect whether the above-described removing agent has broken through. When multiple hydrogen sulfide sensors 11 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 11 to be evaluated using other hydrogen sulfide sensors 11 of different types, and makes it possible to diagnose, for example, whether the hydrogen sulfide sensor 11 is malfunctioning due to the influence of coexisting gases.

[0030] The control unit 21 has a function of controlling the blower 5 based on the detection result of the hydrogen sulfide sensor 11. Specifically, when hydrogen sulfide is detected by the hydrogen sulfide sensor 11, the control unit 21 activates the blower 5 to circulate the air within the housing 3 through the hydrogen sulfide removal unit 4. Even if the flammable hydrogen sulfide gas is generated within the housing 3, combustion of the hydrogen sulfide will not occur unless its concentration reaches the flammable range. Therefore, the control unit 21 may control the blower 5 to adjust the flow rate of air circulating within the housing 3 so that the hydrogen sulfide concentration detected by the hydrogen sulfide sensor 11 is below the lower flammable limit; that is, the control unit 21 may adjust the amount of gas containing hydrogen sulfide flowing into the hydrogen sulfide removal unit 4. Alternatively, from the perspective of reducing power consumption of the blower 5, the control unit 21 may stop the blower 5 when the hydrogen sulfide concentration detected by the hydrogen sulfide sensor 11 falls sufficiently below the lower flammable limit. The control unit 21 also has a function of controlling the output of the battery cells 2, and can limit or stop the output of at least some of the battery cells 2 for safety reasons when hydrogen sulfide is detected by the hydrogen sulfide sensor 11. The control unit 21 may also store the detection results of the hydrogen sulfide sensor 11 for immediate or future use, or transmit them to a server or a blockchain network. If the control unit 21 detects that the hydrogen sulfide removal unit 4 has broken through, as described above, it may output a notification to notify the user of this.

[0031] As described above, it is preferable to start air circulation by operating the blower 5 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 circulation by the blower 5 is stopped while the battery cells 2 are stopped for an extended period of time and the hydrogen sulfide concentration in the housing 3 increases 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 circulation by the blower 5 be started at the latest before the battery cells 2 are started. From this perspective, it is also preferable to provide a separate, independent power source for driving the blower 5, as described above.

[0032] Furthermore, detection of whether or not hydrogen sulfide is being generated within the housing 3 does not have to be performed constantly, but may be performed periodically or as needed. Note that, when two or more hydrogen sulfide sensors 11 are used as described above, one hydrogen sulfide sensor 11 may perform detection constantly, and the other hydrogen sulfide sensor 11 may perform detection only when the other hydrogen sulfide sensor 11 detects hydrogen sulfide. In this way, even if the detection result of one hydrogen sulfide sensor 11 is erroneous, the correct detection result can be obtained by the other hydrogen sulfide sensor 11.

[0033] On the other hand, if suppression of corrosion due to hydrogen sulfide is a priority, air circulation by the blower 5 may be performed independently of hydrogen sulfide detection by the hydrogen sulfide sensor 11. For example, when hydrogen sulfide is generated at a concentration of less than 1 ppm, it is difficult to detect it with an inexpensive hydrogen sulfide sensor, but 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 11, the blower 5 may be operated periodically or steadily to circulate the air inside the housing 3 while circulating it through the hydrogen sulfide removal unit 4. This makes it possible to maintain a low hydrogen sulfide concentration inside the housing 3 and suppress corrosion of the materials of the battery cells 2 and their accessories.

[0034] Hydrogen sulfide is generated due to an abnormality in the battery cell 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 deterioration of the hydrogen sulfide removal unit 4. Even if an attempt is made to remove a large amount of hydrogen sulfide, it may not be possible to remove it completely, resulting in an increase in the hydrogen sulfide concentration in the housing 3. To prepare for such a situation, or simply for backup purposes, this embodiment may also include multiple hydrogen sulfide removal units 4 and multiple air blowers 5. In this case, the multiple air blowers 5 may be independently operated by the control unit 21. For example, if the hydrogen sulfide sensor 11 detects that the hydrogen sulfide concentration in the housing 3 has suddenly increased and exceeded a threshold value, the air blowers 5 to be operated can be switched to ensure hydrogen sulfide removal, thereby introducing hydrogen sulfide-containing gas into a hydrogen sulfide removal unit 4 other than the one that was previously used. Furthermore, the number of air blowers 5 to be operated may be increased or decreased depending on the hydrogen sulfide concentration detected by the hydrogen sulfide sensor 11. On the other hand, even if hydrogen sulfide is generated due to an abnormality in the battery cell 2, the conditions inside the housing 3 (presence or absence of coexisting gases, temperature, humidity, etc.) are not necessarily the same at all times. Therefore, it is preferable that the multiple hydrogen sulfide removal units 4 be of different types (i.e., characteristics), which makes it possible to select and use a hydrogen sulfide removal unit 4 with the optimum characteristics depending on the situation at the time.

[0035] The control unit 21 may be physically separated from the housing 3 as shown in the figure, or may be directly attached to the housing 3. Furthermore, when a battery pack is made up of a plurality of battery modules 1, a control unit 21 does not have to be provided for each battery module 1; for example, one control unit 21 may be provided for the plurality of battery modules 1. In other words, one control unit 21 may function as a control unit that controls the plurality of battery modules 1. In other words, the battery pack may be made up of a plurality of battery modules 1 and one control unit 21.

[0036] Third Embodiment Fig. 3 is a schematic diagram of a battery module according to a third embodiment of the present invention. This embodiment is a modification of the second embodiment, and differs from the second embodiment in that the pressure inside the housing is adjustable. The following description will focus on the differences from the second embodiment.

[0037] When the housing 3 is sealed, there is almost no possibility of contact between the battery cells 2 and the outside air. However, there is a concern that the internal pressure of the housing 3 may increase or decrease in some cases. An increase in internal pressure may occur, for example, when the temperature inside the housing 3 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 by the battery cells 2. A decrease in internal pressure may occur, for example, when the temperature inside the housing 3 decreases due to a decrease in the outside air temperature. To address such changes in internal pressure, the battery module 1 of this embodiment includes a pressure sensor 12 that detects the pressure inside the housing 3 and a pressure adjustment unit 22 that is controlled by the control unit 21 based on the detection result of the pressure sensor 12 and adjusts the pressure inside the housing 3. This makes it possible to prevent excessive increases or decreases in the internal pressure of the housing 3. Furthermore, the output of at least some of the battery cells 2 may be adjusted based on the detection result of the pressure sensor 12. 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 12 falls outside a predetermined range.

[0038] The pressure sensor 12 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 12 is not limited to the position shown in the figure, as long as it can detect the pressure inside the housing 3. The detection result of the pressure sensor 12 may be stored in the control unit 21 for immediate or future use, or may be transmitted to a server or a blockchain network via the control unit 21.

[0039] The pressure adjustment unit 22 is not particularly limited, and examples thereof include an electric valve, a solenoid valve, a relief valve, a compressor, a gas cylinder, and an accumulator. The pressure adjustment unit 22 can be classified into two types: one that releases the internal pressure of the housing 3 and one that pressurizes the housing 3. The former type is suitable when gases such as hydrogen sulfide are generated from the battery cells 2 and the internal pressure of the housing 3 increases; however, there is a concern that the hydrogen sulfide in the housing 3 may leak to the outside when the pressure is released. Therefore, when using a pressure adjustment unit 22 that releases the internal pressure of the housing 3, it is preferable that a hydrogen sulfide removal unit similar to the hydrogen sulfide removal unit 4 is provided at the pressure outlet. On the other hand, the pressure adjustment unit 22 that pressurizes the housing 3 is advantageous in that it not only suppresses a decrease in the internal pressure of the housing 3 but also increases the pressure inside the housing 3 when hydrogen sulfide is generated from the battery cells 2, thereby reducing the amount of hydrogen sulfide released from the battery cells 2. To increase the pressure inside the housing 3, outside air may be introduced into the housing 3 via the pressure adjustment unit 22. In this case, the pressure adjusting unit 22 is preferably provided with a filtering means for removing components (e.g., moisture, oxygen, etc.) contained in the outside air other than the non-reactive gas, thereby further reducing the amount of hydrogen sulfide released from the battery cell 2. 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. The pressure adjusting unit 22 may also be a combination of the two types described above (e.g., an electric valve and a compressor) or an integrated unit, thereby adjusting the pressure inside the housing 3 to an appropriate pressure depending on the situation. The number of pressure adjusting units 22 is not limited to one as shown in the figure, and may be multiple.

[0040] (Fourth embodiment) Fig. 4 is a schematic diagram of a battery module according to a fourth embodiment of the present invention. This embodiment is a modification of the second embodiment, and differs from the second embodiment in that several additional components are added. The following description will focus on the differences from the second embodiment.

[0041] As described above, even if the flammable gas hydrogen sulfide is generated inside the housing 3, combustion of the hydrogen sulfide will not occur unless its concentration reaches the flammable range. On the other hand, no matter what the concentration of hydrogen sulfide is, combustion of the hydrogen sulfide will not occur unless the oxygen concentration inside the housing 3 exceeds the limit oxygen concentration of hydrogen sulfide. Therefore, in this embodiment, an oxygen remover 23 is provided at the outlet 4b of the hydrogen sulfide remover 4 to remove oxygen from the air circulating inside the housing 3 and thereby reduce the oxygen concentration inside the housing 3.

[0042] The oxygen remover 23 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, and the like, and organic oxygen adsorbents containing vitamin C and the like. The location of the oxygen remover 23 is not limited to the location shown in the figure as long as it is located within the housing 3. For example, it may be located at the inlet 4a of the hydrogen sulfide remover 4. The oxygen remover 23 may also be structurally and functionally integrated with the hydrogen sulfide remover 4, thereby reducing the number of parts and facilitating replacement due to deterioration. Alternatively, the oxygen remover 23 may be provided separately from the hydrogen sulfide remover 4. Accordingly, a blower similar to the blower 5 may be provided at any location within the housing 3, including the interior of the oxygen remover 23 (e.g., at the inlet or outlet of the oxygen remover 23). This allows only the blower 5 attached to the hydrogen sulfide removal unit 4 to be operated when only hydrogen sulfide is to be removed, and only the blower attached to the oxygen removal unit 23 to be operated when only oxygen is to be removed, making it possible to respond according to the state of the battery cell 2.

[0043] For the reasons described above, in this embodiment, it is preferable to monitor the oxygen concentration inside the housing 3. To this end, the battery module 1 preferably includes an oxygen sensor 13 that detects the oxygen concentration inside the housing 3. In this case, the control unit 21 may control the output of the blower 5 based on the detection result of the oxygen sensor 13. That is, the output of the blower 5 may be controlled to adjust the flow rate of air circulating inside the housing 3, i.e., the amount of air flowing into the oxygen remover 23, so that the oxygen concentration detected by the oxygen sensor 13 becomes less than the limit 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 13. For example, if the oxygen concentration detected by the oxygen sensor 13 becomes equal to or greater than the limit oxygen concentration of hydrogen sulfide, or if there is a possibility that it will become equal to or greater than a predetermined value that is less than the limit oxygen concentration, the output of at least some of the battery cells 2 may be limited or stopped for safety reasons.

[0044] The oxygen sensor 13 is not particularly limited, and any known oxygen sensor such as a zirconia type, electrochemical type, magnetic type, optical type, laser spectroscopy type, or yellow phosphorus luminescence type can be used. The position of the oxygen sensor 13 is not limited to the position shown in the figure, as long as it can detect the oxygen concentration inside the housing 3. The detection result of the oxygen sensor 13 may be stored in the control unit 21 for immediate or future use, or may be transmitted to a server or a blockchain network via the control unit 21.

[0045] The problem of an increase in the concentration of hydrogen sulfide inside the housing 3 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 housing 3. However, an excessively low temperature inside the housing 3 is undesirable because it may degrade the performance of the battery cells 2. Therefore, the battery module 1 may include a temperature sensor 14 that detects the temperature inside the housing 3 and a temperature adjustment unit 24 that is controlled by the control unit 21 based on the detection result of the temperature sensor 14 and adjusts the air temperature inside the housing 3. This prevents the temperature inside the housing 3 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 housing 3 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 14. 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 14 falls outside a predetermined range.

[0046] The temperature sensor 14 is not particularly limited, and known temperature sensors such as contact and non-contact temperature sensors can be used. Examples of contact temperature sensors include thermocouples, resistance temperature detectors, and thermistors, while examples of non-contact temperature sensors include radiation thermometers. The location of the temperature sensor 14 is not limited to the location shown in the figure, as long as it can detect the temperature inside the housing 3. In the example shown in the figure, only one temperature sensor 14 is installed in the housing 3, but multiple temperature sensors 14 may be installed. In that case, a temperature sensor 14 may be installed near each battery cell 2. The detection results of the temperature sensor 14 may be stored in the control unit 21 for immediate or future use, or may be transmitted to a server or a blockchain network via the control unit 21.

[0047] The temperature adjustment unit 24 is not particularly limited, and may be, for example, a combination of a known cooling device such as an air-cooled, water-cooled, or refrigerant-type device with a known heating device such as an electric heating device or a heat pump. In the illustrated example, the temperature adjustment unit 24 is provided outside the housing 3 to indirectly adjust the temperature of the battery cells 2 via the housing 3, but the location of the temperature adjustment unit 24 is not limited to this and may be, for example, inside the housing 3.

[0048] The hydrogen sulfide removal unit 4 is preferably replaced with a new one periodically or according to usage conditions, and when a predetermined replacement time arrives or replacement is necessary, a notification to notify the user is preferably output from the control unit 21. For example, when a battery pack including the battery module 1 is used in an electric vehicle or a stationary storage battery, the notification is preferably converted into a signal that appeals to the user's five senses, such as sight or hearing, and output. Furthermore, when replacing the hydrogen sulfide removal unit 4, it is preferable that an identifier 25 containing its own identification information be assigned to the hydrogen sulfide removal unit 4, in order to confirm whether the new unit satisfies predetermined usage conditions, such as whether it is a genuine product and its expiration date has not passed.

[0049] The identifier 25 is not particularly limited and 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. Preferably, the identifier 25 is a code, and more preferably, a two-dimensional code such as a QR code (registered trademark). Accordingly, the control unit 21 is equipped with a function for communicating with a reader (not shown) that reads identification information from the identifier 25 and acquiring the reading results. It is preferable that the information necessary for identifying a genuine product is recorded. Based on the acquired identification information, the control unit 21 can determine whether the hydrogen sulfide removal unit 4 satisfies predetermined usage conditions. If the control unit 21 determines that the replaced hydrogen sulfide removal unit 4 does not satisfy the predetermined usage conditions, the control unit 21 may notify the user and disable output from at least some of the battery cells 2. The control unit 21 may transmit the acquired identification information of the hydrogen sulfide removal unit 4, the determination result, the usage status of the hydrogen sulfide removal unit 4, and the like, to a server or a blockchain network. In addition, the reading result of the identifier 25 by the reading device may be sent to a server or blockchain network rather than to the control unit 21, where the above-mentioned judgment is made and the judgment result is sent to the control unit 21.

[0050] Preferably, the control unit 21 directly acquires the usage status (e.g., usage time) of all devices that are communication targets (e.g., the blower unit 5, sensors 11, 13, 14, etc.), and thereby indirectly acquires the usage status of devices that are not communication targets (e.g., the hydrogen sulfide removal unit 4, the oxygen removal unit 23, etc.). Furthermore, the control unit 21 may have a function to predict the lifespan of the hydrogen sulfide removal unit 4 based on the acquired usage status in order to appropriately determine when the hydrogen sulfide removal unit 4 needs to be replaced (its lifespan). Alternatively, in addition to this, the control unit 21 may have a function to transmit 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 4. The acquired usage status and the lifespan prediction results are preferably notified to the user by the control unit 21 or the external management device as needed, thereby enabling planned replacement of the hydrogen sulfide removal unit 4 in accordance with the lifespan prediction. As a result, the possibility of increased maintenance costs due to early replacement when unnecessary, or serious malfunctions due to not replacing the hydrogen sulfide removal unit 4 when necessary, can be reduced. 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 4, 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 4, but from the perspective of prediction accuracy, it is preferable to use AI.

[0051] The timing at which the control unit 21 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 other battery packs including the battery module 1, it is preferable that the data transmission by the control unit 21 be performed 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 21 be powered by a power source independent of the battery cells 2 so that data transmission can be performed reliably even if the output of the battery cells 2 must be stopped.

[0052] The above-described lifespan prediction enables planned replacement of the hydrogen sulfide removal unit 4. However, depending on the usage environment (region) of the battery pack including the battery module 1 and the manufacturing status of the hydrogen sulfide removal unit 4, new or unused hydrogen sulfide removal units 4 may not be available at the time when the end of the lifespan is predicted. That is, if demand for hydrogen sulfide removal units 4 is concentrated in a particular region and a supply shortage occurs as a result, new or unused hydrogen sulfide removal units 4 may not be available in a planned manner. To avoid this, the control unit 21 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 4 required in each region, and based on this, it is possible to secure an optimal number of hydrogen sulfide removal units 4 in stock for each region. Furthermore, the external management device may notify the user of the optimal source for purchasing the hydrogen sulfide removal units 4. As a result, hydrogen sulfide removal units 4 can be obtained when and where they are needed, enabling planned replacement of the hydrogen sulfide removal units 4.

[0053] The above description regarding the lifespan prediction of the hydrogen sulfide removal unit 4 applies to all communication target devices whose usage status is directly acquired by the control unit 21, as well as other devices whose usage status is indirectly acquired (such as the oxygen removal unit 23). After replacing components, including the hydrogen sulfide removal unit 4, 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 4 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 4 can be improved. Such data can also be used to anticipate potential problems when commercializing new types of batteries.

[0054] It goes without saying that the configurations described in the third embodiment can also be applied to this embodiment. In this case, in this embodiment, when oxygen is removed from the housing 3 by the oxygen remover 23, the volume of air in the housing 3 decreases, which may result in a decrease in the pressure inside the housing 3. For this reason, it is preferable to use a pressure adjuster 22 that pressurizes the inside of the housing 3, thereby adjusting the pressure inside the housing 3 to an appropriate pressure. That is, for example, the pressure inside the housing 3 can be adjusted to an appropriate pressure by compensating for the reduced air volume using a compressor or a gas cylinder filled with an inert gas.

[0055] In the above-described embodiment, the battery containing body of the present invention is exemplified as a battery module containing battery cells, but the present invention is not limited to this. For example, a battery pack may be formed by containing a battery module (i.e., modularized battery cells) in the battery containing body of the present invention, or a battery pack may be formed by containing non-modularized battery cells. In this sense, the battery modules exemplified in this specification can also be said to be moduleless battery packs. Note that the battery module contained in the battery containing body of the present invention is not limited to a battery module simply containing battery cells in a housing, but may also be a battery module containing battery cells in the battery containing body of the present invention. In this case, the provision of a dual hydrogen sulfide removal section (active gas removal section) further enhances the safety of the battery pack.

[0056] REFERENCE SIGNS LIST 1 Battery module 2 Battery cell 3 Housing 4 Hydrogen sulfide removal section (active gas removal section) 4a Inlet (of hydrogen sulfide removal section) 4b Outlet (of hydrogen sulfide removal section) 5 Blower section 11 Hydrogen sulfide sensor (gas sensor) 12 Pressure sensor 13 Oxygen sensor 14 Temperature sensor 21 Control section 22 Pressure adjustment section 23 Oxygen removal section 24 Temperature adjustment section 25 Identifier

Claims

1. A battery containing body having: a housing that houses battery cells; an active gas removal section that is provided within the housing and removes active gas generated from the battery cells; and a blower that is provided within the housing and circulates the gas within the housing while circulating it through the active gas removal section.

2. The battery housing according to claim 1, further comprising a control unit that controls the air blower.

3. The battery container according to claim 2, further comprising a gas sensor that detects the presence or concentration of the active gas within the housing, and the control unit activates the blower when the active gas is detected by the gas sensor.

4. The battery housing according to claim 2, further comprising: a pressure sensor that detects the pressure inside the housing; and a pressure adjustment unit that is controlled by the control unit based on the detection result of the pressure sensor and adjusts the pressure inside the housing.

5. The battery container according to claim 1, wherein the active gas is a flammable gas.

6. A battery container as described in claim 5, 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 circulating gas so that the concentration of the flammable gas detected by the gas sensor is below a lower combustion limit value.

7. The battery containing body according to claim 5, further comprising an oxygen removing section provided in the housing for removing oxygen from the circulating gas.

8. A battery container as described in claim 7, comprising: an oxygen sensor that detects the oxygen concentration within the housing; and a control unit that controls the blower to adjust the flow rate of the circulating gas so that the oxygen concentration detected by the oxygen sensor is less than the limit oxygen concentration of the combustible gas.

9. The battery container according to claim 2, 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.

10. The battery containing body according to claim 2, 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.

11. The battery containing body according to claim 2, wherein the control unit predicts the life of the active gas removal unit based on at least the usage status of the air blower unit.

12. The battery containing body according to claim 2, wherein the control unit acquires location information and transmits the acquired location information and at least the usage status of the air blower to the outside.

13. A battery module comprising: a battery housing according to any one of claims 1 to 12; and a battery cell housed in the housing of the battery housing.

14. A battery pack comprising: a battery module according to claim 13; and a control unit that controls the battery module.

15. The battery pack according to claim 14, wherein the battery housing 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 battery cell when the active gas is detected by the gas sensor.

16. A battery pack as described in claim 14, wherein the battery containing body 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 battery cell based on the detection results of at least one of the temperature sensor and the oxygen sensor.

17. A battery pack as described in claim 14, 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, and does not output from the battery cell if it determines that the active gas removal unit does not satisfy the predetermined conditions.

18. The battery pack according to claim 14, wherein the battery housing has a pressure sensor that detects the pressure inside the housing, and the control unit adjusts the output of the battery cell based on the detection result of the pressure sensor.

19. A battery container having: a housing for housing a battery module; an active gas removal section provided within the housing for removing active gas generated from the battery module; and an air blower provided within the housing for circulating the gas within the housing while circulating it through the active gas removal section.

20. A battery pack comprising: a battery containing body according to claim 19; a battery module contained in the housing of the battery containing body; and a control unit that controls the battery module.

21. The battery pack according to claim 20, wherein the battery module is the battery module according to claim 13.

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