Battery cell

Abstract

The battery cell includes a flexible housing, a first electrode, a second electrode, an electrolyte, and at least one seal area. The flexible housing includes a peripheral seal that seals the housing around its periphery. The first electrode and the second electrode each include a first region and a second region protruding from the first region, and the first and second regions of the first and second electrodes are located within the flexible housing. The electrolyte is located between the first region of the first electrode and the first region of the second electrode. The first and second regions of the first and second electrodes and the electrolyte are arranged to define an electrochemical zone contained within the flexible housing. The second regions of the first and second electrodes protrude from the electrochemical zone. The at least one seal area constitutes an area where the inner surfaces of the flexible housing are sealed together. At least one seal region is disposed between the first electrode and the first region of the second electrode and the peripheral seal and is positioned to inhibit electrolyte from leaving the electrochemical zone.

Description

[Technical Field]

[0001] The present disclosure relates to a battery cell and a battery cell arrangement including a battery cell and a clamp. The apparatus disclosed herein may find particular, but not exclusive, application in the field of lithium batteries, such as lithium-sulfur batteries. [Background technology]

[0002] A typical electrochemical cell comprises electrodes in the form of an anode and a cathode, and an electrolyte disposed between the anode and the cathode. The anode, cathode, and electrolyte may be contained within a housing. Electrical connections, such as connection tabs, may be coupled to the housing to provide electrical connection to the anode and cathode of the cell and serve as terminals for the cell.

[0003] The housing for the battery cell may be provided in the form of a flexible housing, such as a flexible pouch. Flexible housings may generally be lightweight compared to rigid housings. Thus, battery cells housed in flexible housings may be particularly applicable in areas where the weight of the battery cell is important. For example, battery cells may be used as power sources for vehicles such as land vehicles, aircraft, and / or spacecraft. In such applications (and / or other applications), it may be desirable to use relatively lightweight battery cells to reduce the overall weight of the vehicle, and thus battery cells having flexible housings may be particularly useful.

[0004] However, battery cells with flexible housings may be prone to swelling due to the flexible nature of the housing. This may be of particular concern in applications where the battery may be exposed to low-pressure conditions and / or high temperatures. For example, battery cells used in aircraft and spacecraft may be exposed to low-pressure conditions when launched to high altitudes.

[0005] It is against this background that the subject matter contained in this application was invented. Summary of the Invention

[0006] According to a first aspect of the present disclosure, there is provided a battery cell including: a flexible housing including a perimeter seal around which the housing is sealed; and first and second electrodes each including a first region and a second region protruding from the first region, the first and second regions of the first and second electrodes being located within the flexible housing and between the first region of the first electrode and the first region of the second electrode. liquid electrolyte a first region of the first electrode and a first region of the second electrode and the liquid electrolyte and arranged to define an electrochemical zone contained within the flexible housing, with second regions of the first electrode and the second electrode protruding from the electrochemical zone. liquid electrolyte and at least one seal area where the inner surfaces of the flexible housing are sealed to each other, the at least one seal area being disposed between the first area of ​​the first electrode and the second electrode and the peripheral seal; liquid electrolyte and a seal region arranged to inhibit the passage of the electrode from leaving (or passing through or exiting) the electrochemical zone.

[0007] The at least one seal area may include a seal area disposed between a first region of the first electrode and the second electrode, a peripheral seal, and a second region of at least one of the first electrode and / or second electrode, and a peripheral seal.

[0008] The at least one sealing region may include a sealing region disposed between the second region of the first electrode and the second region of the second electrode.

[0009] The at least one seal region may include a seal region disposed between the second region of the first electrode and the peripheral seal.

[0010] The at least one seal region may include a seal region disposed between the second region of the second electrode and the peripheral seal.

[0011] The at least one seal area may include a seal area disposed within the peripheral seal and within an outer extent of the first electrode and the second electrode.

[0012] The perimeter seal may define a sealed boundary.

[0013] The at least one sealing area may include a sealing area disposed within a portion of the sealed boundary where no electrodes are located.

[0014] The second region of the first electrode may be offset (or displaced) from the second region of the second electrode.

[0015] The at least one sealing region may include a sealant disposed within the sealing region and adhered to opposing inner surfaces of the flexible housing.

[0016] The first electrode and the second electrode may be substantially planar. The first electrode may be arranged to be substantially parallel to the second electrode.

[0017] The battery cell may further include a first contact tab electrically coupled to the second region of the first electrode and a second contact tab electrically coupled to the second electrode, and the first and second contact tabs may extend through a peripheral seal of the flexible housing.

[0018] At least a portion of the first tab and the second tab may protrude outside the flexible housing and may form an electrical terminal of the battery cell.

[0019] The battery cell may further include a porous separator disposed between the first region of the first electrode and the first region of the second electrode.

[0020] The battery cell may include a plurality of clamping surfaces arranged to receive a clamping force such that application of a clamping force to the clamping surfaces applies a clamping pressure to the electrochemical zone.

[0021] The at least one sealing area may be configured to: liquid electrolyte may be positioned to inhibit the particles from leaving the electrochemical zone.

[0022] The at least one sealing area may be arranged to form part of at least one of the clamping surfaces.

[0023] For example, a sealant disposed in the seal area may serve to sufficiently increase the thickness of the cell in the seal area to cause contact between the clamping element and the flexible housing in the seal area. Thus, a clamping force applied to the clamping surface may serve to apply a clamping force to at least one of the seal areas. The clamping force applied to at least one of the seal areas may liquid electrolyte from entering the seal area and / or being present in the seal area. liquid electrolyte It may also serve to suppress evaporation of the

[0024] According to a second aspect of the present disclosure, there is provided a battery cell arrangement comprising at least one battery cell according to the first aspect and a clamp arranged to apply a clamping force to a clamping surface of the at least one battery cell.

[0025] The clamp may include a first clamp element and a second clamp element disposed on opposing sides of the at least one battery cell, and a clamping device disposed to urge the first clamp element and the second clamp element together to exert a clamping force on the at least one battery cell.

[0026] The clamping device may be arranged to urge the first clamping element and the second clamping element together.

[0027] The clamping device may be arranged to bias the first clamping element and the second clamping element towards each other.

[0028] The clamp may be arranged to apply uniaxial pressure to the clamping surface.

[0029] The clamp is liquid electrolyte The clamping force may be arranged to apply sufficient clamping force to inhibit vaporization of the

[0030] The clamp is liquid electrolyte The pressure sensor may be arranged to apply a clamping pressure substantially equal to or greater than the difference between the vapor pressure of the battery cell and the atmospheric pressure to which the battery cell is exposed.

[0031] For example, atmospheric pressures as low as about 30 mbar liquid electrolyte For example, the atmospheric pressure to which the battery cell is exposed may be less than atmospheric pressure at sea level, e.g., less than about 500 mbar.

[0032] In some instances, liquid electrolyte The battery cell may be subjected to a clamping pressure substantially equal to or greater than the difference between the vapor pressure of the battery and atmospheric pressure, down to as low as about 5 mbar. For example, the battery cell may be subjected to atmospheric pressures of less than 30 mbar in some scenarios.

[0033] In some instances, liquid electrolyte A clamping pressure may be applied that is substantially equal to or greater than the difference between the vapor pressure of the gas and atmospheric pressure of less than 5 mbar.

[0034] In some instances, liquid electrolyteA clamping pressure substantially equal to or greater than the difference between the vapor pressure of the battery and atmospheric pressure up to a vacuum pressure condition may be applied. For example, the battery cell may be exposed to a vacuum pressure condition (e.g., space use) of substantially 0 mbar. Even when the battery cell is exposed to a vacuum pressure condition, liquid electrolyte In such an example, the clamping pressure may be sufficient to suppress vaporization of liquid electrolyte The vapor pressure may be substantially equal to or greater than the vapor pressure of the

[0035] liquid electrolyte References to vapor pressure are at approximately 20°C. liquid electrolyte For example, at 20°C, liquid electrolyte and the atmospheric pressure to which the battery cell is exposed (e.g., less than about 500 mbar, less than about 30 mbar, less than about 5 mbar, or may be as low as a substantially complete vacuum).

[0036] In some instances, a clamping pressure greater than zero and up to about 10 GPa can be applied.

[0037] According to a third aspect of the present disclosure, there is provided a method of clamping at least one battery cell according to the second aspect, the method comprising applying a clamping force to a clamping surface of the at least one battery cell.

[0038] The clamping force may be applied to opposing sides of the at least one battery cell.

[0039] Applying a clamping force may include applying uniaxial pressure to the clamping surface.

[0040] The applied clamping force is liquid electrolyte may be sufficient to suppress evaporation of the

[0041] The applied clamping force is determined by the applied clamping pressure. liquid electrolyteThe pressure may be substantially equal to or greater than the difference between the vapor pressure of the battery cell and the atmospheric pressure to which the battery cell is exposed.

[0042] For example, atmospheric pressures as low as about 30 mbar liquid electrolyte For example, the battery cell may be exposed to an atmospheric pressure that is less than atmospheric pressure at sea level, e.g., less than about 500 mbar.

[0043] In some instances, liquid electrolyte A clamping pressure substantially equal to or greater than the difference between the vapor pressure of the battery cell and atmospheric pressure, down to as low as about 5 mbar, may be applied. For example, the battery cell may be exposed to atmospheric pressures of less than 30 mbar in some scenarios.

[0044] In some instances, liquid electrolyte A clamping pressure may be applied that is substantially equal to or greater than the difference between the vapor pressure of the gas and atmospheric pressure of less than 5 mbar.

[0045] In some instances, liquid electrolyte A clamping pressure substantially equal to or greater than the difference between the vapor pressure of the battery and atmospheric pressure up to a vacuum pressure condition may be applied. For example, the battery cell may be exposed to a vacuum pressure condition (e.g., space use) down to substantially 0 mbar. Even when the battery cell is exposed to a vacuum pressure condition, liquid electrolyte In such an example, the clamping pressure may be sufficient to suppress vaporization of liquid electrolyte The vapor pressure may be substantially equal to or greater than the vapor pressure of the

[0046] liquid electrolyte References to vapor pressure are at approximately 20°C. liquid electrolyte For example, at 20°C, liquid electrolyteand the atmospheric pressure to which the battery cell is exposed (e.g., less than about 500 mbar, less than about 30 mbar, less than about 5 mbar, or may be as low as a substantially complete vacuum).

[0047] In some instances, a clamping pressure greater than zero and up to about 10 GPa can be applied.

[0048] Within the scope of this application, it is expressly intended that the various aspects, embodiments, examples, and alternatives, particularly individual features thereof, described in the preceding paragraphs, claims, and / or the following description and drawings, may be taken independently or in any combination. That is, all examples and / or features of any example may be combined in any manner and / or combination, except where such features are incompatible. Applicant reserves the right to modify any originally filed claims or to submit new claims accordingly. This includes the right to amend any originally filed claim to rely on and / or incorporate any feature of any other claim, even though not claimed in that manner. [Brief explanation of the drawings]

[0049] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying figures. [Figure 1A] FIG. 1 is a schematic diagram of a battery cell having a flexible housing. [Figure 1B] FIG. 1 is a schematic diagram of a battery cell having a flexible housing. [Figure 2A] 1C is a schematic diagram of a first electrode and a second electrode that form part of the battery cell of FIGS. 1A and 1B. FIG. [Figure 2B] 1C is a schematic diagram of a first electrode and a second electrode that form part of the battery cell of FIGS. 1A and 1B. FIG. [Figure 3A] FIG. 2 is a schematic diagram of a cross-sectional view of the battery cell of FIGS. 1A and 1B. [Figure 3B]FIG. 2 is a schematic diagram of a cross-sectional view of the battery cell of FIGS. 1A and 1B. [Figure 3C] FIG. 2 is a schematic diagram of a cross-sectional view of the battery cell of FIGS. 1A and 1B. [Figure 4A] FIG. 2 is a schematic diagram showing a battery cell arrangement including battery cells and clamps. [Figure 4B] FIG. 2 is a schematic diagram showing a battery cell arrangement including battery cells and clamps. [Figure 5] FIG. 2 is a schematic diagram of a battery cell including a sealing area. [Figure 6A] FIG. 6 is a schematic cross-sectional view of the battery cell of FIG. 5. [Figure 6B] FIG. 6 is a schematic cross-sectional view of the battery cell of FIG. 5. [Figure 6C] FIG. 6 is a schematic cross-sectional view of the battery cell of FIG. 5. DETAILED DESCRIPTION OF THE INVENTION

[0050] Before describing particular embodiments of the present invention, it is to be understood that the present disclosure is not limited to the particular cells, batteries, or methods described herein, and that the terminology used herein is used only to describe particular embodiments, and is not intended to limit the scope of the claims.

[0051] In describing and claiming the battery cells, batteries, and methods of the present invention, the following terminology is used: the singular forms "a," "an," and "the" include the plural unless the context clearly dictates otherwise. Thus, for example, reference to a "battery cell" includes reference to one or more of such elements.

[0052] FIG. 1A is a schematic diagram of a battery cell 100 having a flexible housing 101. FIG. 1B is a schematic diagram of a cross section of the battery cell 100 showing the components of the battery cell 100 located within the flexible housing 101. The battery cell 100 may include any suitable electrochemical cell. For example, the cell may include a lithium cell. Suitable lithium cells include lithium-ion cells, lithium-air cells, lithium-polymer cells, and lithium-sulfur cells.

[0053] The battery cell depicted in Figures 1A and 1B is of a pouch type as is commonly known in the art. The battery cell 100 includes a flexible housing 101 (e.g., a pouch) and a first electrode 111 and a second electrode 114 (of which only a second region 114b is visible in Figure 1B) located within the flexible housing 101. The battery cell 100 includes a flexible housing 101 (e.g., a pouch) and a first electrode 111 and a second electrode 114 (of which only a second region 114b is visible in Figure 1B) located within the flexible housing and between the first electrode 111 and the second electrode 114. liquid electrolyte (not shown in FIGS. 1A and 1B). The flexible housing 101 is sealed around its perimeter with a perimeter seal 105. The perimeter seal includes electrodes 111, 114 and liquid electrolyte 100 is sealed within the flexible housing 101.

[0054] 2A and 2B are schematic diagrams of a first electrode 111 and a second electrode 114, respectively. As shown in FIG. 2A, the first electrode 111 is composed of a first region 111a and a second region 111b. Similarly, as shown in FIG. 2B, the second electrode 114 is composed of a first region 114a and a second region 114b. The second regions 111b and 114b of the electrodes 111 and 114 protrude from the first regions 111a and 114a of the electrodes. As shown in FIGS. 2A and 2B, the first regions 111a and 114a of the electrodes 111 and 114 are generally larger than the second regions 111b and 114b. In particular, the widths wa of the first regions 111a and 114a of the electrodes 111 and 114 are larger than the widths w of the second regions 111b and 114b of the electrodes. bThat is, the width of the second regions 111b and 114b is greater than the width w of the first regions 111a and 114a. a The entire area does not protrude beyond the first region 111, 114a.

[0055] Typically, the first regions 111a, 114a of the electrodes 111, 114 constitute the regions where the electrochemical reaction occurs, and the second regions 111b, 114b of the electrodes are provided to form an electrical connection with the electrodes, i.e., current is typically passed between the electrodes via the connections formed between the second regions 111b, 114b of the electrodes 111, 114.

[0056] One of the electrodes 111, 114 is a cathode, and the other of the electrodes 111, 114 is an anode. For example, the first electrode 111 may be a cathode and the second electrode 114 may be an anode, or vice versa. Typically, the electrodes 111, 114 are comprised of at least a conductive substrate (e.g., a current collector). In some examples, an electroactive material may be disposed on all or a portion of the conductive substrate. For example, the conductive substrate may be formed (e.g., cut from a base material) to form both the first 111a, 114a and second 111b, 114b regions of the electrodes 111, 114. In some examples, an electroactive material may be deposited on at least a portion of the conductive substrate. For example, an electroactive material may be deposited on all or a portion of the first regions 111a, 114a of the electrodes 111, 114.

[0057] The electrodes 111, 114 may be formed of any suitable material, depending on the battery cell chemistry. In an illustrative example, the battery cell 100 may include a lithium-sulfur cell. In such an example, the first electrode 111 may be provided in the form of a cathode comprising a current collector having an electroactive material disposed thereon. The current collector may be comprised of, for example, a metal foil such as aluminum foil. The electroactive material may include, for example, electroactive sulfur materials comprising elemental sulfur, Li2S, sulfur-based organic compounds, sulfur-based inorganic compounds, and sulfur-containing polymers.

[0058] The electroactive sulfur material may be mixed with a conductive material. The resulting mixture may be coated onto a current collector, for example, as an electroactive matrix. The conductive material may be any suitable material, such as a solid material formed of carbon. For example, the conductive material may be composed of carbon black, carbon fiber, graphene, and / or carbon nanotubes.

[0059] The second electrode 114 may be provided in the form of an anode formed from a conductive substrate made of lithium. For example, the conductive substrate may be formed from a sheet of lithium metal or a lithium metal alloy.

[0060] While the above describes an illustrative example in which battery cell 100 is a lithium-sulfur battery, in other examples, battery cell 100 may take different forms and may be formed from other materials. For example, as previously mentioned, battery cell 100 may be any form of cell, such as, but not limited to, a lithium-ion, sodium-ion, lithium-air, and / or lithium-polymer cell, and correspondingly, may be formed from any suitable material (as known in the art).

[0061] As mentioned above, the second regions 111b, 114b of the electrodes 111, 114 are typically used to establish electrical connection with the electrodes 111, 114. Referring again to FIGS. 1A and 1B, the battery 100 further includes first and second contact tabs 108a, 108b electrically connected to the first electrode 111 and the second electrode 114, respectively. In particular, the contact tabs 108a, 108b are electrically coupled to the second regions 111b, 114b of the electrodes 111, 114. That is, the first contact tab 108a is electrically coupled to the second region 111b of the first electrode 111, and the second contact tab 108b is electrically coupled to the second region 114b of the second electrode 114. The contact tabs 108a, 108b may be coupled to the second regions 111b, 114b of the electrodes using any suitable bonding such as, for example, using a conductive adhesive, soldering, riveting, crimping, clamping and / or welding (e.g., ultrasonic welding or laser welding).

[0062] The contact tabs 108a, 108b may be formed of any suitable conductive material. For example, the contact tabs 108a, 108b may be formed of a metal such as aluminum, nickel, and / or copper. In some examples, the first and second contact tabs 108a, 108b may be composed of different materials. For example, in an exemplary embodiment, the first contact tab 108a may be composed of aluminum, and the second contact tab 108b may be composed of nickel. In an example in which the battery cell 100 constitutes a lithium-sulfur cell (such as the example described above with reference to the materials used in the electrodes), the first contact tab 108a, which is coupled to the cathode 111 (which may comprise a current collector formed of aluminum foil), may be composed of aluminum. The second contact tab 108b, which is coupled to the anode 114 (which may be composed of lithium metal or a lithium metal alloy), may be composed of nickel.

[0063] As clearly shown in FIG. 1B , the second regions 111b, 114b of the first and second electrodes 111, 114 are offset from one another. For example, in the perspective view shown in FIG. 1B , the first and second electrodes 111, 114 are horizontally offset from one another and spaced apart from one another. This offset allows the contact tabs 108a, 108b to be coupled to the first and second electrodes 111, 114, respectively, without jeopardizing electrical contact between the contact tabs 108a, 108b. Thus, the contact tabs 108a, 108b are isolated from one another and can establish independent electrical connections to the first and second electrodes 111, 114. For example, as shown in FIGS. 1A and 1B , the contact tabs 108a, 108b protrude from the flexible housing 101 and can establish external connections with the battery cell 101. Thus, the contact tabs 108 a , 108 b function as terminals for the battery cell 101 .

[0064] 3A, 3B, and 3C are schematic diagrams illustrating a cross section of the battery cell 100 of FIGS. 1A and 1B. The cross section shown in FIG. 3A is taken along line AA shown in FIGS. 1A and 1B. The cross section shown in FIG. 3B is taken along line BB shown in FIGS. 1A and 1B. The cross section shown in FIG. 3C is taken along line CC shown in FIGS. 1A and 1B. It will be understood that the components illustrated in FIGS. 3A-3C (and other figures) are not shown to scale. For example, at least some of the dimensions of one or more of the components illustrated in the figures may be enlarged or reduced for ease of illustration.

[0065] As shown in FIGS. 3A to 3C, a separator 119 is provided between a first electrode 111 and a second electrode 114. In particular, the separator 119 is arranged to prevent electrical contact between the first electrode 111 and the second electrode 114. As described above, the battery cell 100 is located between the first electrode 111 and the second electrode 114 within the flexible housing 101. liquid electrolyte The separator 119 may be made of a porous substrate, allowing ions to move between the first and second electrodes 111, 114. liquid electrolyte , may therefore be located within separator 119 and is generally indicated by the arrow labeled 121 in FIGS. 3A-3C.

[0066] Separator 119 may have a porosity of greater than about 30%. For example, separator 119 may have a porosity of greater than about 50%, or even greater than about 60%. Suitable separators 119 may include, for example, a mesh formed from a polymeric material. Suitable polymers include polypropylene, nylon, and polyethylene.

[0067] Any suitable liquid electrolyte 121 may also be used. liquid electrolyte121 may contain an organic solvent and a lithium salt. Suitable organic solvents include ethers, esters, amides, amines, sulfoxides, sulfamides, organophosphates, ionic liquids, carbonates, sulfones, etc. Examples include ethylene carbonate, dimethyl carbonate, tetrahydrofuran, 2-methyltetrahydrofuran, methyl propyl propionate, ethyl propyl propionate, methyl acetate, 1,2-dimethoxyethane, 1,3-dioxolane, diglyme (2-methoxyethyl ether), triglyme, tetraglyme, butyrolactone, 1,4-dioxane, 1,3-dioxane, hexamethylphosphoamide, pyridine, dimethyl sulfoxide, tributyl phosphate, trimethyl phosphate, N,N,N,N-tetraethylsulfamide, sulfones, and mixtures thereof.

[0068] Suitable electrolyte salts include lithium salts. Suitable lithium salts include lithium hexafluorophosphate, lithium hexafluoroarsenate, lithium nitrate, lithium perchlorate, lithium trifluoromethanesulfonimide, lithium bis(trifluoromethanesulfonyl)imide, lithium bis(oxalato)borate, and lithium trifluoromethanesulfonate. In some instances, combinations of salts may be employed. For example, lithium triflate may be used in combination with lithium nitrate. The lithium salts are preferably used at a concentration of 0.1 to 5M, preferably 0.5 to 3M. liquid electrolyte It may be present in

[0069] As is well understood, during operation of a battery cell (e.g., charging and / or discharging the cell), liquid electrolyte Ions in the electrode 111 and the electrode 114 move between the electrodes, and an electrochemical reaction occurs at the electrodes 111 and 114. Therefore, the first electrode 111 and the second electrode 114 and liquid electrolyte defines the electrochemical zone 103 where electrochemical reactions occur during operation of the battery cell 100. As previously mentioned, typically, liquid electrolyte121 is located between the first 111a, 114a regions of the electrodes 111, 114. Furthermore, in at least some examples, the electroactive material of the first and / or second electrodes 111, 114 may be limited to the first regions 111a, 114a of the electrodes 111, 114 and absent from the second regions 111b, 114b. Thus, the second regions 111b, 114b of the electrodes may be located outside the electrochemical zone 103. That is, the second regions 111b, 114b of the electrodes 111, 114 protrude from the electrochemical zone 103.

[0070] As previously mentioned, the flexible housing 101 is sealed at its periphery by the peripheral seal 105. Thus, the flexible housing 101 liquid electrolyte The flexible housing 101 is a sealed housing that houses the electrodes 121 and 111, 114 and protects these components from the external environment. The seal of the flexible housing 101 may be considered to form a sealed pouch. The flexible housing 101 may be formed, for example, from a composite material of a metal and a polymer. For example, the flexible housing 101 may be made of aluminum laminated with a polymer (e.g., polypropylene formed inside the flexible housing and nylon formed outside the flexible housing).

[0071] As can be seen from the illustrated example, the battery cell 100 may be generally flat and plate-shaped. For example, the battery cell may be generally rectangular in shape. In such an example, the flexible housing 101 may be formed from opposing sheets of flexible material sealed around their peripheries. For example, two pieces of flexible material may be disposed on either side of the electrodes 111, 114 and sealed together around the peripheries of the electrodes 111, 114 so that the electrodes 111, 114 form a sealed housing.

[0072] As mentioned above, the perimeter seal 105 may be formed by sealing surfaces of flexible material together to form the housing 101. The perimeter seal 105 may be formed around at least a portion of the perimeter of the flexible housing 101. The perimeter seal 105 may be formed by sealing the materials together using any suitable technique, such as, for example, heat treating, heat sealing, and / or using adhesives / bonding materials.

[0073] As described above, the first and second electrodes 111, 114 and liquid electrolyte 121 may be completely enclosed within the flexible housing 101 by the perimeter seal 105 so as to be isolated from the atmosphere surrounding the battery cell 100. For example, the second regions 111b, 114b of the electrodes 111, 114 may protrude from the electrochemical zone 103 but are contained within (i.e., do not protrude from) the flexible housing 101.

[0074] In the illustrated example, the perimeter seal 105 is formed around the outer extents of the electrodes 111, 114. For example, the perimeter seal 105 may be formed substantially around the smallest rectangular perimeter that encloses both the first regions 111a, 114a and the second regions 111b, 114b of the first electrode 111 and the second electrode 114 (referred to herein as the outer extent of the electrodes). The perimeter seal 105 can be thought of as sealing the perimeter of the flexible housing 101. For example, the perimeter seal 105 can be generally located in the area between the outer extents of the electrodes 111, 114 and the outer edge of the flexible housing 101.

[0075] In the example shown, the perimeter seal 105 is formed by sealing material together around the entire perimeter of the flexible housing 101. However, in some examples, it may be possible to form a sealed flexible housing 101 without sealing the material forming the housing around its entire perimeter. For example, the flexible housing 101 may be formed from a single sheet of flexible material that is bent around one edge of the electrodes 111, 114 to form a first portion of the sheet of material on one side of the electrodes 111, 114 and a second portion of the sheet of material on the opposing side of the electrodes 111, 114. The first and second portions of flexible material may then be sealed together around the remaining three edges of the electrodes 111, 114 to form a sealed housing in which the electrodes 111, 114 reside. In such an example, the housing 101 is still considered to include a peripheral seal 105 around which the housing 101 is sealed, where part of the peripheral seal 105 is formed by a continuation of the housing material itself (e.g., at the edges where the material is folded around the electrodes 111, 114).

[0076] Although the above describes an example in which the battery cell 100 includes a first electrode 111 and a second electrode 114, in some examples, the battery cell 100 may include two or more electrodes. For example, the battery cell 100 may include multiple electrodes 111 functioning as cathodes and multiple electrodes 114 functioning as anodes. In some examples, multiple cathodes and multiple anodes may be arranged as a stack. For example, multiple cathodes and multiple anodes may be arranged alternately. For example, multiple cathodes and multiple anodes may be arranged alternately, with each alternate electrode in the stack being a cathode and an anode being located between each cathode. Furthermore, an arrangement including two or more electrodes may include an electrode functioning as a cathode located between two electrodes functioning as anodes, and an electrode functioning as an anode located between two electrodes functioning as cathodes. As described above, a separator 121 may be arranged between adjacent electrodes to electrically insulate them. For example, a separator 121 may be provided between a pair of adjacent electrodes. liquid electrolyte 121 may be provided between each pair of electrodes.

[0077] In an arrangement including two or more electrodes, multiple electrodes of the same type may be electrically connected to each other. For example, multiple electrodes functioning as cathodes may be electrically connected to each other. Similarly, multiple electrodes functioning as anodes may be electrically connected to each other. Electrodes may also be electrically connected to each other by electrically connecting the second regions 111b, 114b of the electrodes together. For example, the second regions 111b of multiple electrodes functioning as cathodes may be in contact with each other. Similarly, the second regions 114b of multiple electrodes functioning as anodes 114b may be in contact with each other.

[0078] As described above, the second region 111b of the first electrode 111 may be offset from the second region 114b of the second electrode 114. In some examples, multiple electrodes in the form of the aforementioned first electrodes 111 may be provided to function as cathodes. Similarly, multiple electrodes in the form of the aforementioned second electrodes 114 may be provided to function as anodes. That is, multiple electrodes 111 functioning as cathodes 111 may include second regions 111b that are substantially aligned with one another. Additionally, multiple electrodes 114 functioning as anodes 114 may include second regions 114b that are substantially aligned with one another but that are offset and spaced apart from the second region 111b of the cathode 111. This may allow the second regions 111b of the cathodes 111 to be connected to one another and the second regions 114b of the anodes 114 to be connected to one another while maintaining electrical isolation between the cathodes 111 and the anodes 114. The first contact tab 108a may be electrically connected to the second region 111b of the cathode 111, and the second contact tab 108b may be electrically connected to the second region 114b of the anode 114 to provide a terminal for the battery cell.

[0079] As mentioned above, a battery cell 100 of the type described above may include a first electrode 111 and a second electrode 114, or may include a plurality of first electrodes 111 and a plurality of second electrodes 114. It will be understood that any description and teachings provided herein with reference to a battery cell 100 including a first electrode 111 and a second electrode 114 may also apply to a battery cell including a plurality of first electrodes 111 and a plurality of second electrodes 114, and vice versa.

[0080] As described above, the electrodes 111, 114 and liquid electrolyte The housing 100 containing the cells 121 is sealed and flexible. As such, the flexible housing 101 may be prone to expansion. Significant expansion of the housing is generally undesirable because it places strain on the housing 101 and risks damage, leakage, and / or rupture of the housing 101. Furthermore, expansion of the flexible housing may be undesirable when the cells are located in close proximity to other components. For example, in some applications, multiple cells may be located adjacent to one another (e.g., in a stack of cells). In such an arrangement, substantial expansion of one or more cells may cause adjacent cells to come into contact with other cells and exert pressure on one another.

[0081] Expansion of the battery cells 100 may be of particular concern in applications in which one or more battery cells are exposed to pressure conditions lower than atmospheric pressure at sea level. For example, battery cells 100 of the type described above may find application in aircraft and / or spacecraft flown at altitudes where the ambient pressure is significantly lower than atmospheric pressure at sea level; for example, in the case of a spacecraft, the ambient pressure may be close to or a complete vacuum. Exposure to low-pressure conditions (e.g., when flying an aircraft at high altitude) may cause some expansion of the flexible housing 101.

[0082] The expansion of the flexible housing 101 occurs when the ambient pressure liquid electrolyteThis can be particularly problematic in situations where the pressure is close to or lower than the vapor pressure of the battery cells 121. The flexibility of the housing 101 means that when the battery cells 101 are unconstrained, the pressure inside the housing 101 may be approximately the same as the pressure of the atmosphere immediately surrounding the housing 101. liquid electrolyte If the vapor pressure is close to or less than 121, liquid electrolyte 121 can vaporize and result in significant expansion. liquid electrolyte It will be appreciated that vaporization and expansion of 121 can cause significant expansion of flexible housing 101.

[0083] When operated at low ambient pressure liquid electrolyte The risk of vaporizing 121 is liquid electrolyte This may be particularly relevant for battery cells 100 that have relatively high vapor pressures. For example, lithium-sulfur batteries have relatively high vapor pressures compared to other battery chemistries. liquid electrolyte For example, a typical lithium-sulfur battery liquid electrolyte The vapor pressure of the typical lithium-ion battery liquid electrolyte The vaporization pressure may be higher than that of the

[0084] For example, a typical operating temperature of a battery cell may be about 20° C. In a purely illustrative example, liquid electrolyte may be used in lithium-sulfur batteries. A liquid electrolyte consisting of 1,2-dimethoxyethane may have a vapor pressure of about 48 mmHg (20°C). Another example is a liquid electrolyte containing 1,3-dioxolane. liquid electrolyte may be used in lithium-sulfur batteries. liquid electrolyte may have a vapor pressure of about 70 mmHg (at 20°C).

[0085] Used in lithium-sulfur batteries liquid electrolyte In contrast to the liquid electrolyteAn example of such a solvent may include dimethyl carbonate, which may have a vapor pressure of approximately 18 mmHg (at 21.1°C). liquid electrolyte Other examples include diethyl carbonate, which has a vapor pressure of about 10 mmHg (23.8°C), propylene carbonate, which has a vapor pressure of 0.13 mmHg (20°C), or ethylene carbonate, which has a vapor pressure of 0.02 mmHg (36.4°C).

[0086] Generally, the type commonly used in lithium-sulfur batteries liquid electrolyte is therefore commonly used in lithium-ion batteries. liquid electrolyte Therefore, lithium-sulfur batteries can have a vaporization pressure higher than that of lithium-ion batteries when operated at a lower pressure. liquid electrolyte There may be a high risk of vaporization.

[0087] In addition to, or instead of, operating at low ambient pressures, the battery cell 100 may operate at relatively high temperatures. liquid electrolyte The vaporization pressure of the battery is typically a function of temperature and generally increases with increasing temperature. Therefore, operation of the battery cell 100 at relatively high temperatures liquid electrolyte This may involve operating the battery cell 100 while the vapor pressure of 121 is relatively high. Thus, operation at relatively high temperatures may be achieved even at atmospheric pressure. liquid electrolyte As explained in relation to the low pressure operation of the battery cell, high temperatures can also increase the risk of vaporization of 121. liquid electrolyte This can cause vaporization of the fuel and subsequent undesirable expansion of the flexible housing. Any teachings presented herein relating to operation of the battery at low pressures may be equally applicable to operation of the battery at high temperatures.

[0088] As previously mentioned, battery cells 100 of the type described above that are housed within a flexible housing 101 may be prone to swelling of the flexible housing 101. This is particularly true when batteries are used in the battery cell 100. liquid electrolyteAdditionally or alternatively, this may be when the battery is exposed to ambient pressure conditions close to or below the vapor pressure of the battery.

[0089] According to an example of the present disclosure, expansion of the flexible housing 101 of the battery cell may be reduced or mitigated by applying pressure to the battery cell 100. For example, a clamping pressure may be applied to the battery cell 100 having the flexible housing 101 to increase the pressure inside the housing 101. FIG. 4A is a schematic diagram illustrating a battery cell arrangement 200 according to an example of the present disclosure, including the battery cell 100 and a clamp 201 positioned to apply a clamping force to the battery cell 100. The battery cell 100 is generally in the configuration previously described and depicted in FIGS. 1-3. In FIG. 4A, the same reference numerals are used to indicate components corresponding to those previously described in connection with FIGS. 1-3. Accordingly, a detailed description of the components of the battery cell 100 will not be provided with reference to FIG. 4A. The depiction shown in FIG. 4A provides a cross-sectional view of the battery cell 100, corresponding to cross-section B-B shown in FIG. 3B.

[0090] 4A, clamp 201 is provided in the form of first clamping element 201a, second clamping element 201b, and clamping device 202. First clamping element 201a, 201b are generally rigid structures and may be provided, for example, in the form of rigid plates 201a, 201b. Clamping elements 201a, 201b may be constructed from any suitable material, such as, for example, carbon fiber.

[0091] The clamping device 202 is arranged to hold the clamping elements 201a, 201b such that, under at least some conditions, the clamping elements 201a, 201b exert a clamping force on the battery cell 100. The clamping device 202 may be provided in any suitable form, such as, for example, one or more flexible straps, springs, or rigid elements that contact both the first and second clamping elements 201a, 201b. In the depiction of FIG. 4A , the clamping device 202 is provided in the form of a single element arranged to clamp the first and second elements 201a, 201b together. In some examples, the clamping device 202 may include multiple such elements.

[0092] Battery cells 100 of the type described herein may include multiple clamping surfaces arranged to receive a clamping force. For example, the battery cell 100 may be shaped to include opposing clamping surfaces to which a clamping force can be applied, such that application of the clamping force to the clamping surfaces applies a clamping pressure to the electrochemical zone 103. As previously mentioned, battery cells 100 of the type described herein may be provided in a generally flat plate shape. In such an example, the opposing surfaces having a generally flat plate shape may function as clamping surfaces to which a clamping force may be applied.

[0093] The clamping elements 201a, 201b may have dimensions that are substantially equal to or greater than the equivalent dimensions of the clamping surfaces of the battery cell 100. For example, the width and / or height of the clamping elements 201a, 201b may be substantially equal to or greater than the corresponding width and / or height of the clamping surfaces of the battery cell 100. This may allow a clamping force to be applied across most or all of the clamping surfaces of the battery cell 101, limiting the area into which the battery cell 101 may be allowed to expand.

[0094] In the example shown in Figure 4A, clamping elements 201a, 201b are positioned on either side of the battery cell 100 and adjacent to the clamping surfaces of the battery cell 100. The clamping elements 201a, 201b may apply a clamping force to the clamping surfaces to apply clamping pressure to the electrochemical zone 103 of the cell 100. The general direction of the clamping force is indicated by the arrow designated by reference numeral 210 in Figure 4A and may exert a uniaxial clamping pressure.

[0095] In some examples, the clamping device 202 may be arranged to clamp the clamping elements 201 a, 201 b and apply a clamping force to the battery cell 100 even when the battery cell 100 is not in a state prone to expansion. For example, the clamp 201 may apply a clamping force to the battery cell 100 at atmospheric conditions above sea level. In such examples, the clamping device 202 may be arranged with a pre-strain. For example, the clamping device 202 may be comprised of one or more tensioned straps and / or springs.

[0096] In other examples, the clamping device 202 may be positioned without pre-strain such that the clamping elements 201a, 201b do not apply a substantial clamping force to the battery cell 100 in the absence of expansion of the battery cell 100. For example, the clamping device 202 may be positioned to hold the clamping elements 201a, 201b in a substantially fixed relationship to one another. In such an arrangement, the clamping elements 201a, 201b may be positioned in contact with or closely adjacent to the battery cell 100. When the battery cell 100 begins to undergo expansion (e.g., due to a decrease in ambient pressure and / or an increase in temperature), the clamping surfaces of the battery cell 100 may exert an expansion force on the clamping elements 201a, 201b. Because the clamping elements 201a, 201b are held in a substantially fixed relationship to one another, the expansion force of the battery cell 100 applies a clamping force to the battery cell 100, which in turn applies a clamping pressure to the electrochemical zone 103.

[0097] The clamp 201 provides a clamping force that is sufficient to hold the battery cell 100 in place under all pressure conditions under which the battery cell 100 is designed to operate. liquid electrolyte The clamp 201 may be positioned to apply sufficient clamping pressure to the battery cell 100, and in particular to the electrochemical zone 103, to prevent or at least inhibit vaporization of the P c ≧P v -P min The clamping pressure P is given by c where P V teeth liquid electrolyte The vapor pressure of 121 is P min is the minimum atmospheric pressure at which the battery cell 100 will operate. For example, the battery cell may be operable from atmospheric pressure down to pressures of about 30 mbar or less. In some examples, the battery cell may operate at even lower pressures, such as about <5 mbar or less, or even at pressures near or at a full vacuum.

[0098] The clamping pressure that can be applied to the battery cell can be provided, for example, in the form of a constant volume clamp, which does not actively apply pressure to the battery cell but merely restricts the volume of the cell to inhibit cell expansion. Alternatively, a non-zero clamping pressure can be applied to the battery cell. For example, a clamping pressure greater than zero, up to about 10 GPa, can be applied to the battery cell.

[0099] While examples in which the clamp 201 is arranged to apply a clamping force to a single battery cell 100 have been described above and are shown in FIG. 4A , in some examples, the clamp 201 may be arranged to apply a clamping force to multiple battery cells 100. FIG. 4B is a schematic diagram illustrating a battery cell arrangement 200b according to one embodiment of the present disclosure, including multiple battery cells 100 and a clamp 201 arranged to apply a clamping force to the multiple battery cells 100. In the example shown in FIG. 4B , the multiple battery cells 101 are arranged in close proximity to one another (e.g., in a stack of battery cells 101) and / or in contact with one another. The clamp 201 is arranged to apply a clamping force to the multiple battery cells 101. For example, the clamp 201 is arranged around the periphery of the stack of battery cells 101. The clamp 201 may be similar to or the same as the clamp 201 described above with reference to FIG. 4A . For example, any of the features described above with reference to the clamp 201 arranged to clamp a single battery cell may similarly apply to the clamp 201 arranged to clamp multiple battery cells 101.

[0100] Any descriptions and teachings presented herein with reference to clamping a single battery cell 101 may also apply to instances in which the clamp 201 is arranged to apply a clamping force to multiple battery cells 101, and vice versa.

[0101] As described above, application of a clamping force to the battery cell 100 can prevent or at least suppress expansion of the flexible housing 101 of the battery cell 100. This, for example, can allow the battery cell 100 to operate under low-pressure conditions, reducing the risk of damage to the battery cell 100 or surrounding components when exposed to low-pressure conditions. In particular, the above description has described an example in which the clamping pressure is applied to the electrochemical zone 103. For example, as seen in FIG. 4A , the clamping elements 201a and 201b are positioned in contact with clamping surfaces of the battery cell 101 that generally correspond to the size and shape of the first regions 111a and 114a of the electrodes 111 and 114. Therefore, the clamping force is applied to the regions corresponding to the first regions 111a and 114a of the electrodes 111 and 114. As a result, the electrochemical zone 103 and the electrodes 111 and 114 located within the electrochemical zone 103 are compressed. liquid electrolyte A clamping pressure is applied to 121.

[0102] Furthermore, applying a clamping force to the battery cell 100 can prevent or reduce expansion of the flexible housing 101 of the battery cell 100 when the battery cell 100 is operated under high temperature conditions. The clamping force may reduce the risk of damage to the battery cell 100 or surrounding components when exposed to high temperature conditions. As explained above, at a certain pressure, high temperature conditions can: liquid electrolyte This increases the vapor pressure of the battery cell 100, and even at atmospheric pressure, the vapor pressure may become comparable to the atmospheric pressure of the battery cell. liquid electrolyte Vaporization of 121 may occur.

[0103] Located in the electrochemical zone 103 (between the first regions 111a, 114a of the electrodes 111, 114) liquid electrolyteWhile clamping pressure may be applied to the flexible housing 101 in the first expansion region 151, in some configurations, there may be regions of the battery cell 100 where little or no clamping pressure is applied. For example, in the example shown in FIG. 4A , there is a labeled first expansion region 151, where the flexible housing 101 is not in contact with the clamping elements 201a and 201b. As a result, little or no clamping pressure may be applied to the first expansion region 151. When the battery cell 101 shown in FIGS. 1-4 operates under low pressure conditions, the pressure in the first expansion region 151 may therefore decrease (in the absence of clamping pressure in this region) with the ambient pressure conditions to which the battery cell 100 is exposed. For example, the pressure in the first expansion region 151 may decrease below the pressure in the electrochemical zone 103, while the electrochemical zone 103 is maintained at a higher pressure by the application of a clamping force.

[0104] As a result, some liquid electrolyte 121 may be drawn from the electrochemical zone 103 into the expansion region 151 of the fist (or may already be present in the first region 151), and the pressure in the first expansion region 151 liquid electrolyte It may vaporize when the pressure drops below the vaporization pressure of 121. liquid electrolyte When 121 vaporizes, it generally expands and may cause the flexible housing 101 to expand.

[0105] In the example shown in FIG. 4A, the battery cell 100 liquid electrolyte When operating at pressure conditions close to or below the vapor pressure of 121, the flexible housing 101 therefore liquid electrolyte 121 may be located, forcing expansion in any area not receiving clamping pressure (e.g., first expansion area 151). As previously mentioned, expansion of flexible housing 101 is generally undesirable because it can strain and potentially damage flexible housing 101. For example, expansion of flexible housing 101 can cause flexible housing 101 to burst.

[0106] liquid electrolyteThe disadvantages of vaporization of 121 were discussed above in connection with the expansion of flexible housing 101. liquid electrolyte The vaporization of 121 can also have a detrimental effect on the performance of the battery cell 100. For example, liquid electrolyte 121 and not located in the electrochemical zone 103 liquid electrolyte 121 is generally not available to perform its role in an electrochemical cell. liquid electrolyte is unavailable to contribute to the formation of a solid-electrolyte-interface (SEI) at the surface of the lithium anode in a lithium metal battery. liquid electrolyte The evaporation of 121 can generally degrade the cyclability of the battery cell 100.

[0107] In the above example, the flexible housing 101 was described as being prone to expansion in the first expansion region 151 located between the second region 111b of the first electrode 111 and the second region 114b of the second electrode 114. In general, the flexible housing 101 may be prone to expansion in any region that allows a decrease in pressure within the housing 101 in response to a decrease in the atmospheric pressure at which the battery cell 100 is maintained. For example, expansion of the flexible housing 101 may occur in regions that are not subjected to clamping pressure.

[0108] In addition to the first expansion region 151 described above and depicted in FIG. 4A (and also labeled in FIGS. 1 and 3B), the battery cell 100 may include additional expansion regions through which the flexible housing 101 may expand when exposed to low-pressure conditions. For example, as labeled in FIG. 1B, there may be a second expansion region 152 and / or a third expansion region 153 that are not subject to clamping pressure. Corresponding to the reasons discussed above with reference to the first expansion region 151, the second expansion region 152 and / or the third expansion region 153 may be prone to expansion when the battery cell 101 is exposed to low-pressure conditions.

[0109] The expansion regions 151, 152, and 153 may be present in regions of the battery cell 100 where the thickness of the battery cell 100 is less than the maximum thickness of the battery cell 100 (i.e., the maximum thickness in other regions of the battery cell 100). For example, the first expansion region 151, the second expansion region 152, and the third expansion region 153 are located in regions where a portion of the first electrode 111 or the second electrode 114 is not present. For example, the first expansion region 151 is located in the gap between the second region 111b of the first electrode 111 and the second region 114b of the second electrode 114. The second expansion region 152 is located in the gap between the second portion 111b of the first electrode 111 and the peripheral seal 105. The third expansion region 153 is located in the gap between the second portion 114b of the second electrode and the peripheral seal 105.

[0110] Because the expansion regions 151, 152, 153 do not include portions where the electrodes 111, 114 are located, the thickness of the battery cell 100 in the expansion regions 151, 152, 153 is generally smaller than the thickness in other regions of the battery cell 100. For example, the thickness of the battery cell 100 in the expansion regions 151, 152, 153 is generally smaller than the thickness of the battery cell 100 in the electrochemical zone 103. Furthermore, the thickness of the expansion regions 151, 152, 153 may generally be smaller than the thickness in the regions occupied by the second regions 111b, 114b of the electrodes 111, 114.

[0111] 4A, in areas such as first expansion region 151 (and similarly second 152 and third 153 expansion regions) where the thickness of battery cell 100 is less than the maximum thickness of the cell, flexible housing 101 may not be in contact with clamping elements 201 a, 201 b. As a result, little or no clamping pressure is applied in expansion regions 151, 152, 153, and thus flexible housing 101 in these areas may expand freely.

[0112] The expansion regions 151, 152, and 153 are also regions inside the perimeter seal 105 and are therefore not held together by the perimeter seal 105. Each of the expansion regions 151, 152, and 153 is located between the first portions 111a, 114a of the electrodes 111, 114 and the perimeter seal 105. As can be seen, for example, in FIGS. 1, 3A-3C, and 4A, the perimeter seal 105 is outside the extent of the second regions 111b, 114b of the electrodes 111, 114. For example, in the orientation shown, the perimeter seal 105 is located above the upper extent of the second regions 111b, 114b of the electrodes 111, 114. This is believed to be because it is generally desirable to keep the second regions 111b, 114b of the electrodes 111, 114 sealed within the housing 101, for example, to prevent the electrodes 111, 114 from contacting the ambient atmosphere.

[0113] Furthermore, it may not be possible to form a seal directly with the second regions 111b, 114b of the electrodes 111, 114. For example, it may not be possible to seal the flexible housing 101 directly to the second regions 111b, 114b of the electrodes 111, 114. For example, electrodes 111, 114 made of lithium are highly reactive and may ignite if a seal is attempted between such an electrode and the flexible housing 101.

[0114] As described above, the structure of the battery cell 100 having the flexible housing 101 may include areas that are prone to expansion when operated at low pressures. These areas may also be prone to expansion when a clamping force is applied to the battery cell 100.

[0115] Figure 5 is a schematic diagram of a battery cell 1000 according to one embodiment of the present disclosure. Figures 6A, 6B, and 6C are schematic cross-sectional views of the battery cell 1000 of Figure 5. The cross-section shown in Figure 6A is taken along line DD shown in Figure 5. The cross-section shown in Figure 6B is taken along line E-E shown in Figure 5. The cross-section shown in Figure 6C is taken along line FF shown in Figure 5.

[0116] The battery cell 1000 shown in Figures 5 and 6A-6C includes many of the same or corresponding components as the battery cell 100 described above with reference to Figures 1-4. In Figures 5 and 6A-6C, the same reference numerals are used to indicate components that correspond to those described above with reference to Figures 1-4. Accordingly, a detailed description of the same or corresponding components with reference to Figures 5 and 6A-6C will not be provided herein.

[0117] The battery cell 1000 shown in Figures 5 and 6A-6C differs from the cell 100 of Figures 1-4 in that the battery cell 1000 further includes sealing regions 161-163. The sealing regions 161-163 are generally located within the expansion regions 151-153 described above with reference to Figures 1-4. Any explanation or teaching provided herein with reference to the locations of the expansion regions 151-153 is equally applicable to the locations of the sealing regions 161-163, and vice versa.

[0118] Sealing areas 161-163 constitute areas where the inner surfaces of flexible housing 101 are sealed together. For example, sealing areas 161-163 may include a sealant, such as adhesive and / or tape, arranged to seal together opposing inner surfaces of flexible housing 101. Additionally or alternatively, sealing areas 161-163 may be formed using heat sealing to bond the inner surfaces of flexible housing 101 together.

[0119] The sealing areas 161 to 163 are liquid electrolyte 121 from leaving the electrochemical zone 103. For example, the sealing areas 161 to 163 are liquid electrolyte 121 may be positioned to inhibit the passage of fluid from exiting the electrochemical zone 103 and entering the expansion region described above. By sealing the flexible housing 101 together at the sealing regions 161-163, liquid electrolyte121 moves and is exposed to a low pressure condition. Furthermore, sealing the flexible housing 101 together at the sealing regions 161-163 may inhibit expansion of the flexible housing 101 in these regions. For example, the sealing regions 161-163 may act to increase the rigidity of the housing 101 in these regions, reducing or preventing expansion of the housing 101. Advantageously, these effects reduce strain on the housing 101, thereby reducing the risk of damage to the housing 101 (such as bursting of the housing 101). Furthermore, liquid electrolyte By preventing the electrolyte from leaving the electrochemical zone 103, any degradation in the performance of the battery cell 1000 can be reduced.

[0120] Furthermore, the presence of the sealed regions 161-163 prevents electrical leakage to any unsealed space between the flexible housing 101 and the second regions 111b, 114b of the first and second electrodes 111, 114. liquid electrolyte (These unsealed spaces can be seen, for example, in FIGS. 3A and 3C.) For example, sealed regions 161-163 allow flexible housing 101 to fit tightly around electrodes 111, 114, reducing any unsealed spaces, thereby reducing the risk of electrical shock to the areas between flexible housing 101 and second regions 111b, 114b of first and second electrodes 111, 114. liquid electrolyte The flow of may be inhibited.

[0121] 6A-6C, the sealing regions 161-163 may serve to increase the thickness of the battery cell 1000 in these regions (compared to when no seals are provided in these regions). For example, the sealing regions 161-163 may include a sealant disposed between (and sealing together) opposing inner surfaces of the flexible housing 101. The volume of sealant provided in the sealing regions 161-163 may be sufficient to substantially increase the thickness of the cell 1000 in these regions.

[0122] In at least some examples, an increase in thickness of the cell 1000 in the seal region may be sufficient to cause contact between the clamping elements 201a, 201b (not shown in FIGS. 6A-6C) and the flexible housing 101 in the seal regions 161-163. Accordingly, a clamping force may be applied near the seal regions 161-163, resulting in a clamping pressure acting on the seal regions 161-163. That is, at least one of the seal regions 161, 162, 163 may form part of a clamping surface positioned to receive the clamping force, such that the clamping pressure is applied to the electrochemical zone and / or at least one of the seal regions 161, 162, 163. Such clamping pressure may serve to increase the pressure inside the flexible housing 101 near the seal regions 161-163. For example, the pressure inside the flexible housing 101 may be increased by: liquid electrolyte 121. liquid electrolyte Advantageously, evaporation of 121 can be suppressed or prevented.

[0123] In some examples, the sealing regions 161-163 may be arranged to fill substantially the entire expansion regions 151-153. For example, the inner surface of the flexible housing 101 may be sealed together over substantially all of the first expansion region 151 located between the second regions 111b, 114b of the electrodes 111, 114. In some examples, the inner surface of the flexible housing 101 may be sealed together over only a portion of the expansion regions 151-153. That is, the sealing regions 161-163 to which the flexible housing is sealed may occupy only a portion of the expansion regions 151-153. For example, spots of sealant may be added to the expansion regions 151-153 that do not fill the entire expansion regions 151-153. It has been found that such an arrangement may be sufficient to inhibit expansion of the housing 101 in the expansion regions 151-153 without sealing the entire expansion regions 151-153. Furthermore, during manufacturing of the battery cell 1000, it may be simpler and easier to seal only a portion of the expansion regions 151-153 as opposed to sealing substantially all of the expansion regions 151-153.

[0124] It is understood that in at least some instances, the sealant in the sealing areas 161, 162, 163 may provide a synergistic effect in conjunction with clamping of the cell 1000. For example, applying clamping pressure to the battery cell 100 (e.g., with clamp 201) may cause the sealing areas 161, 162, 163 to: liquid electrolyte acts to inhibit the electrochemical zone 103 from leaving the electrochemical zone 103, while liquid electrolyte For example, by applying clamping pressure to the electrochemical zone 103, liquid electrolyte toward the sealing areas 161, 162, 163, and if no sealant is present in the sealing areas 161, 162, 163, liquid electrolyte The presence of sealant in the seal areas 161, 162, 163 can cause liquid electrolytefrom leaving the electrochemical zone 103 (e.g., under clamping pressure) and entering the seal areas 161, 162, 163 where they are vaporized. That is, the sealant in the seal areas and the application of the clamping force cooperate to: liquid electrolyte This can suppress evaporation of the fuel and expansion of the battery cell.

[0125] Additionally, as previously mentioned, in at least some instances, the sealant within the seal areas 161, 162, 163 may increase the thickness of the seal area such that at least one seal area 161, 162, 163 forms a portion of a clamping surface against which clamping pressure may be applied. Such clamping pressure may increase the thickness of the seal area in the vicinity of the seal areas 161-163. liquid electrolyte This can serve to increase the pressure inside the flexible housing 101 in the vicinity of the sealing areas 161-163 so as to advantageously reduce or prevent vaporization of 121.

[0126] As described above, at least one of the sealing regions 161 to 163 is liquid electrolyte The sealing regions 161-163 may be positioned to inhibit the electrodes 111, 114 from moving away from the electrochemical zone 103 of the battery cell 1000. Generally, the sealing regions 161-163 may be positioned between the first regions 111a, 114a of the electrodes 111, 114 and the perimeter seal. The sealing regions 161-163 may also be positioned between the first regions 111a, 114a of the electrodes 111, 114, the perimeter seal, and at least one second region 111b, 114b of the electrodes 111, 114. For example, the sealing regions 161-163 may be generally surrounded (e.g., on four sides) by the perimeter seal 105, the first regions 111a, 114a of the electrodes, and at least one second region 111b, 114b of the electrodes 111, 114.

[0127] 5 and 6A-6C are disposed between first regions 111a, 114a of electrodes 111, 114, peripheral seal 105, and at least one second region 111b, 114b of the electrodes. In particular, first seal region 161 is disposed between first regions 111a, 114a of electrodes 111, 114, peripheral seal 105, second region 111b of first electrode 111, and second region 114b of second electrode 114. Second seal region 162 is disposed between first regions 111a, 114a of electrodes 111, 114, second region 111b of first electrode 111, and peripheral seal 105. The third seal area 163 is disposed between the first areas 111 a , 114 a of the electrodes 111 , 114 , the second area 114 b of the second electrode 114 , and the peripheral seal 105 .

[0128] In at least some examples, at least one sealing area 161-163 may be located within the outer area of ​​the electrodes 111, 114. For example, the outer area of ​​the electrodes 111, 114 may be the smallest rectangle that encompasses the entire first electrode 111 and the second electrode 114. The outer circumferential area of ​​the electrodes 111, 114 shown in the figures roughly coincides with the inner circumferential area of ​​the peripheral seal 105, which has a generally rectangular shape. For example, as shown in FIG. 5, the sealing areas 161-163 are located within the inner area of ​​the peripheral seal 105 and the outer area of ​​the electrodes 111, 114. Note that the sealing areas 161-163 may also be located in gaps in the outer peripheries of the electrodes 111, 114 where the electrodes 111, 114 are not located. In other words, the peripheral seal 105 may define a sealing boundary that is, for example, substantially rectangular. The sealing areas 161-163 may be located in portions of the sealed boundary (eg, rectangular) where the electrodes 111, 114 are not located.

[0129] Generally, the sealing areas 161-163 may be located outside the electrochemical zone 103 and within the confines of the perimeter seal 105. The sealing areas 161-163 may also be liquid electrolyte 121 may be located in any suitable area to inhibit it from leaving the electrochemical zone 103 .

[0130] Specific examples have been described herein in which a battery cell comprises a first electrode and a second electrode. However, as noted herein, a battery cell may comprise more than two electrodes. For example, a battery cell of the type contemplated herein may include multiple cathodes and multiple anodes. Descriptions and teachings presented herein with respect to a battery cell comprising two electrodes are equally applicable to a battery cell comprising more than two electrodes, and vice versa.

[0131] It will be understood that the figures are provided merely as schematic representations of the devices disclosed herein, and that at least some of the figures are not drawn to scale. For example, at least some of the components shown in the figures may have increased or decreased dimensions relative to other components for ease of illustration, and it will be understood that the relative dimensions of the components shown should not be construed as limiting.

[0132] It is understood that features, integers, properties, compounds, or materials described in connection with a particular aspect, embodiment, or example of the invention are applicable to other aspects, embodiments, or examples described herein, to the extent not incompatible therewith. All features disclosed herein (including any accompanying claims, abstract, and drawings), and / or all steps of any method or process so disclosed, may be combined in any combination, except combinations in which at least some of such features and / or steps are mutually exclusive. The invention is not limited to the details of any of the foregoing examples. The invention extends to any novel one or any novel combination of features disclosed herein (including any accompanying claims, abstract, and drawings), or any novel one or any novel combination of steps of any method or process so disclosed. [Explanation of symbols]

[0133] 100, 1000... battery cells 101 ... Flexible housing 103 … Electrochemical Zone 105...perimeter seal 108a ... Second contact tab 108b ... First contact tab 111 ... first electrode 111a ... first region of first electrode 111b ... second region of the first electrode 114 ... second electrode 114a ... first region of second electrode 114b ... second region of second electrode 119 ... Separator 121... liquid electrolyte 151 ... First expansion region 152 ... Second expansion region 153 ... Third expansion region 161 … 1st seal region 162 … Second seal region 163 ... Third seal region 200... battery cells 201... Clamp 201a, 201b ... clamping elements 202 ... Clamping Device 210 … Clamping pressure

Claims

1. a flexible housing including a perimeter seal around which the housing is sealed; a first electrode and a second electrode each including a first region and a second region protruding from the first region; a liquid electrolyte located between the first region of the first electrode and the first region of the second electrode; a plurality of clamping surfaces arranged to receive a clamping force, the application of the clamping force to the clamping surfaces applying a clamping pressure to the electrochemical zone; and at least one sealing area where the inner surfaces of the flexible housing are sealed to one another; Equipped with a first region and a second region of the first electrode and the second electrode are disposed within the flexible housing; a first region of the first electrode and the second electrode and the liquid electrolyte are arranged to define an electrochemical zone contained within the flexible housing, and a second region of the first electrode and the second electrode protrudes from the electrochemical zone; the at least one seal region is disposed between first regions of the first and second electrodes and the perimeter seal and is configured to inhibit the liquid electrolyte from leaving the electrochemical zone when a clamping force is applied to a clamping surface; The at least one sealing area is positioned to form a portion of at least one of the clamping surfaces.

2. 10. The battery cell of claim 1, wherein the at least one seal area includes a first area of ​​the first electrode and second electrode, a seal area disposed between the perimeter seal and at least one second area of ​​the first electrode and / or second electrode.

3. The battery cell of claim 1 , wherein the at least one sealing area includes a sealing area disposed between the second area of ​​the first electrode and the second area of ​​the second electrode.

4. The battery cell of claim 1 , wherein the at least one seal area includes a seal area disposed between a second area of ​​the first electrode and the peripheral seal.

5. The battery cell of claim 1 , wherein the at least one seal area includes a seal area disposed between a second area of ​​the second electrode and the peripheral seal.

6. 6. The battery cell of claim 1, wherein the at least one sealing area includes a sealing area disposed within the perimeter seal and within outer extents of the first electrode and the second electrode.

7. The battery cell of any preceding claim, wherein the perimeter seal defines a sealed boundary.

8. The battery cell of claim 7 , wherein the at least one sealed area includes a sealed area disposed within a portion of the sealed boundary where no electrodes are located.

9. The battery cell of any one of claims 1 to 8, wherein the second region of the first electrode is offset from the second region of the second electrode.

10. The battery cell of any one of claims 1 to 9, wherein the at least one sealing area includes a sealant disposed in the sealing area and adhered to opposing inner surfaces of the flexible housing.

11. 11. The battery cell according to claim 1, wherein the first electrode and the second electrode are substantially flat, and the first electrode is arranged to be substantially parallel to the second electrode.

12. 12. The battery cell of claim 1, further comprising: a first contact tab electrically coupled to a second region of the first electrode; and a second contact tab electrically coupled to the second electrode, the first contact tab and the second contact tab extending through a peripheral seal of the flexible housing.

13. 13. The battery cell of claim 12, wherein at least a portion of the first and second contact tabs protrude outside the flexible housing and form electrical terminals of the battery cell.

14. 14. The battery cell of claim 1, further comprising a porous separator disposed between the first region of the first electrode and the first region of the second electrode.

15. At least one battery cell according to any one of claims 1 to 14, and a clamp positioned to apply a clamping force to a clamping surface of the at least one battery cell; [0023] The battery cell arrangement,

16. 16. The battery cell arrangement of claim 15, wherein the clamp comprises a first clamp element and a second clamp element disposed on opposite sides of the at least one battery cell, and a clamping device disposed to urge the first clamp element and the second clamp element together to apply a clamping force to the at least one battery cell.

17. 17. The battery cell arrangement of claim 16, wherein the clamping device is arranged to hold the first clamping element and the second clamping element in fixed relationship to one another.

18. 17. The battery cell arrangement of claim 16, wherein the clamping device is positioned to press the first clamping element and the second clamping element together.

19. 19. A battery cell arrangement according to any one of claims 15 to 18, wherein the clamp is arranged to apply uniaxial pressure to the clamping surface.

20. 20. A battery cell arrangement according to any one of claims 15 to 19, wherein the clamps are arranged to apply a clamping force sufficient to inhibit evaporation of the liquid electrolyte.

21. 21. The battery cell arrangement of claim 20, wherein the clamp is positioned to apply a clamping pressure substantially equal to or greater than the difference between the vapor pressure of the liquid electrolyte and atmospheric pressure applied to the battery cell.

22. A method for clamping at least one battery cell according to any one of claims 1 to 14, comprising the step of applying a clamping force to a clamping surface of the at least one battery cell.

23. 23. The method of claim 22, wherein the clamping force is applied to opposing sides of the at least one battery cell.

24. 24. The method of claim 22 or 23, wherein the step of applying a clamping force comprises applying uniaxial pressure to the clamping surface.

25. The method of any one of claims 22 to 24, wherein the applied clamping force is sufficient to inhibit evaporation of the liquid electrolyte.

26. 26. The method of any one of claims 22 to 25, wherein the applied clamping force is substantially equal to or greater than the difference between the vapor pressure of the liquid electrolyte and the atmospheric pressure applied to the battery cell.

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