JP2024512955A - Biodegradable electrochemical device with barrier layer - Google Patents

Abstract

An electrochemical device is disclosed that can include an electrolyte composition disposed between an anode and a cathode, and a water vapor barrier that can include a biodegradable material, the water vapor barrier Located to prevent water vapor from escaping from the chemical device. The water vapor barrier can further include polylactic acid or a metallized coating. The water vapor barrier can further include multiple layers and has a water vapor transmission rate (WVTR) of 2% by weight or less over 24 hours. Water vapor barrier embodiments may also include a polymeric biodegradable material or a metallized coating disposed on the biodegradable material. The water vapor barrier can also include multiple layers and have a water vapor transmission rate (WVTR) of 1 mg per cm 2 or less over 24 hours.

Description

Embodiments or implementations disclosed by the present invention are directed to biodegradable electrochemical devices, solid aqueous electrolytes thereof, and moisture barriers therefor.

The number of batteries produced worldwide is continuously increasing as a result of the increasing need for portable and remote power sources. In particular, some new technologies require batteries to power implantable electronic devices. For example, implantable electronics, such as portable and wearable electronics, Internet of Things (IoT) devices, patient medical monitoring, structural monitoring, environmental monitoring, smart packaging, etc., rely on batteries for power supply. There is. Although conventional batteries can be partially recycled, there are currently no batteries on the market that are environmentally friendly or biodegradable. Thus, the increased production and use of conventional batteries results in a commensurate increase in environmentally toxic and hazardous waste if the batteries are not properly disposed of or recycled. In view of the foregoing, there is a need to develop biodegradable batteries, particularly for applications that utilize disposable batteries for a limited period of time before being discarded.

Additionally, to meet the demand for flexible, low cost, medium or low performance batteries, all-printed batteries have been developed that are marketed as single-use disposable batteries. However, none of these fully printed cells are biodegradable.

It is generally accepted that one of the greatest challenges in the production of biodegradable batteries is the development of biodegradable polymer electrolytes, which are the primary polymer base of all printed batteries. It is a constituent component of In addition, a further challenge is the development of such biodegradable polymer electrolytes that can also be printed using existing printing techniques.

Conventional biodegradable polymer electrolytes often include a combination of a biodegradable polymer and a conductive salt. To obtain a biodegradable polymer electrolyte, the biodegradable polymer and conductive salt are dissolved in a solvent, and the solvent is subsequently evaporated at a relatively slow rate to produce a solid polymer electrolyte film. These conventional biodegradable polymer electrolytes often have low ionic conductivity at ambient temperatures (e.g., less than about 10 ^-5 S/cm at RT) due to the low mobility of ions in the biodegradable polymer. There is a problem. However, sufficient conductivity means that the polymer electrolyte is heated to a sufficient temperature (i.e., operating temperature) to allow polymer chain mobility, thereby allowing ions to move more freely through the polymer electrolyte structure. This can be achieved if it becomes possible. Sufficient conductivity can also be achieved by incorporating additives that suppress the crystallinity of the polymer electrolyte, thereby reducing its operating temperature. Thus, biodegradable polymer electrolytes that can operate with sufficient conductivity at room temperature are limited.

In addition to the aforementioned weaknesses, conventional biodegradable polymer electrolytes also suffer from very long manufacturing processes due to the time required to evaporate the solvent during manufacturing. For example, vacuum and/or temperature assisted evaporation often requires several hours to evaporate the solvent for preparing conventional biodegradable polymer electrolytes, thus Polymer electrolytes have limited compatibility with high-throughput printing processes where successive layers must be printed on top of each other in minutes.

Printable, biodegradable electrochemical devices, their solid aqueous electrolytes, and methods for synthesizing and fabricating them are available, including current collectors, cathode/anode materials, binders, adhesives, and electrolytes. Layers of various materials need to be printed with high fidelity and precision. Additionally, retention of moisture or water content within the aqueous electrolyte is critical to battery performance through maintenance of solubilized salts for good ionic conductivity, and biodegradable printed batteries such as these Biodegradable batteries suffer from reduced lifetime due to water loss through evaporation through biodegradable substrates, such as polylactic acid (PLA) films. There is a need to improve the moisture retention rate of these cells, especially the electrolyte layer, by reducing the WVTR (water vapor transmission rate). At the same time, there remains a challenge in achieving this hermetic property for surrounding electrochemical devices while maintaining or reducing the non-biodegradable content of biodegradable printed batteries, which is currently not possible in printed batteries. It is not possible to use conventional relatively thick, non-biodegradable foil "pouches" such as those found in Li-ion batteries to seal the battery.

The following presents a simplified summary in order to provide a basic understanding of some aspects of one or more embodiments of the present teachings. This summary is not an extensive overview and is not intended to identify key or critical elements of the invention's teachings or to delineate the scope of the disclosure. Rather, its primary purpose is simply to present one or more concepts in a simplified form as a prelude to the more detailed description that is presented later.

An electrochemical device is disclosed. Electrochemical devices also include an anode and a cathode. The device also includes an electrolyte composition disposed between the anode and the cathode, and a water vapor barrier that can include a biodegradable material, the water vapor barrier being arranged to prevent water vapor from escaping from the electrochemical device. Ru. The water vapor barrier can further include polylactic acid. The water vapor barrier may further include a metallized or aluminum metallized coating. The water vapor barrier can further include multiple layers. The electrochemical device can further have a water vapor transmission rate (WVTR) of 2% by weight or less over 24 hours.

Water vapor barrier embodiments can also include biodegradable materials including polymers. The water vapor barrier can also include a metallized coating disposed on the biodegradable material. The water vapor barrier can include a polymer, which can further include a polylactic acid, metallized or aluminum metallized coating. The water vapor barrier can also include multiple layers and have a water vapor transmission rate (WVTR) of 1 mg per cm ² or less over 24 hours.

The accompanying figures, which are incorporated in and constitute a part of this specification, illustrate embodiments of the teachings of the present invention. These and/or other aspects and advantages of embodiments of the present disclosure will be apparent and more readily appreciated from the following description of various embodiments, taken in conjunction with the accompanying figures.

1 illustrates an exploded view of an exemplary biodegradable electrochemical device in a side-by-side configuration in accordance with one or more disclosed embodiments; FIG. FIG. 2 illustrates an exploded view of another exemplary biodegradable electrochemical device in a stacked configuration in accordance with one or more disclosed embodiments. FIG. 12 illustrates a cross-sectional view of a comparative example of a fully assembled substitute for a biodegradable battery assembly with a water vapor barrier in accordance with one or more embodiments. 2 illustrates a cross-sectional view of an embodiment of a fully assembled substitute for the electrochemical device assembly of Example 1 with a water vapor barrier, according to one or more embodiments. FIG. FIG. 1 illustrates a cross-sectional view of a fully assembled substitute embodiment for the electrochemical device assembly of Example 2 having a water vapor barrier, according to one or more embodiments. FIG. 3 illustrates a cross-sectional view of an embodiment of a fully assembled substitute for the electrochemical device assembly of Example 3 with a water vapor barrier, according to one or more embodiments. 1 illustrates a cross-sectional view of an example of an alternative to an electrochemical device assembly having a multilaminate enclosure structure according to the present disclosure. Plots of water loss per square centimeter (in milligrams) versus time (in days) for the comparative example in FIG. Illustrated.

It is noted that some details of the figures have been simplified and drawn to facilitate an understanding of the teachings of the present invention, rather than to maintain exact structural accuracy, detail, and scale.

The following descriptions of various exemplary embodiments are merely exemplary in nature and are not intended to limit the disclosure, its application, or uses in any way.

Ranges used throughout are used as shorthand to describe any and all values within the range. Any value within the range can be selected as the end of the range. Additionally, all references cited herein are incorporated by reference in their entirety. In the event of a conflict between definitions in this disclosure and definitions in a cited reference, the present disclosure will control.

Unless otherwise specified, all percentages and amounts expressed herein and elsewhere in the specification should be considered to refer to percentages by weight. The amount given is based on the active mass of the material.

Additionally, all numerical values are expressed as "about" or "approximately" and take into account experimental errors and variations that would be expected by those skilled in the art. It should be recognized that all numerical values and ranges disclosed herein, whether or not "about" is also used, are approximating values and ranges. As used herein, the term "about" means, in conjunction with a numerical value, ±0.01% (inclusive), ±0.1% (inclusive) of that numerical value; May be ±0.5% (inclusive), ±1% (inclusive), ±2% (inclusive), ±3% (inclusive). ), that value may be ±5% (inclusive), ±10% (inclusive), or ±15% (inclusive). I would also like to be recognized for this. It is further recognized that when a numerical range is disclosed herein, any number falling within the range is also specifically disclosed.

As used herein, the term "or" is an inclusive operator and is equivalent to the term "and/or" unless the context clearly dictates otherwise. The term "based on" is not exclusive and allows for being based on additional elements not listed, unless the context clearly dictates otherwise. In the specification, the enumeration "at least one of A, B, and C" refers to multiple instances of A, B, or C, A, B, or C, or A/B, A/C, B /C, A/B/B/B/B/C, combinations of A/B/C, and the like. Additionally, throughout the specification, the meanings of "a," "an," and "the" include plural references. The meaning of "in" includes "in" and "on."

Reference will now be made in detail to exemplary embodiments of the present teachings, examples of which are illustrated in the accompanying figures. Wherever possible, the same reference numbers are used throughout the figures to refer to the same, similar, or like parts.

Biodegradable electrochemical devices are disclosed herein. As used herein, the term "biodegradable" or "biodegradable material" means capable of being broken down by living organisms, particularly microorganisms within a landfill, within a reasonable time; It can refer to materials, components, substances, devices, etc. designed as such. The materials, components, substances, devices, etc. can be decomposed into water, naturally occurring gases such as carbon dioxide and methane, biomass, or combinations thereof. As used herein, the expressions "biodegradable electrochemical device" or "biodegradable device" may refer to an electrochemical device or devices, respectively, of which at least one or more of the The components are biodegradable. In some cases, a majority or a significant number of the biodegradable electrochemical devices or components of the biodegradable device are biodegradable. In other cases, all of the polymeric components of the biodegradable electrochemical device or biodegradable device are biodegradable. For example, the polymers and/or other organic-based components of the electrochemical devices are biodegradable, while the inorganic materials of the electrochemical devices disclosed herein, including metals and/or metal oxides, are biodegradable. It does not have to be biodegradable. It should be recognized that it is generally accepted that an entire electrochemical device is considered biodegradable if all polymeric and/or organic-based components of the device are biodegradable. As used herein, the term "compostable" can refer to items that can be composted or otherwise disposed of in an earth-friendly or environmentally friendly manner. Compostable materials can be considered a subset category of biodegradable materials, and additional specific environmental temperatures or conditions may be required to destroy the compostable materials. Although the term compostable is not synonymous with biodegradable, these terms do not mean that the conditions necessary to destroy or degrade biodegradable materials are the conditions necessary to destroy compostable materials. may be used interchangeably if they are considered similar. As used herein, the term or expression "electrochemical device" can refer to a device that converts electricity into a chemical reaction and/or vice versa. Exemplary electrochemical devices may be or include, but are not limited to, batteries, photosensitized solar cells, electrochemical sensors, electrochromic glasses, fuel cells, electrolyzers, and the like.

As used herein, the term or expression "environmentally friendly electrochemical device" or "environmentally friendly device" indicates a minimal, lower amount of toxicity to the ecosystem or the general environment. , or an electrochemical device or device, respectively, that does not exhibit any toxicity. In at least one embodiment, the electrochemical devices and/or components thereof disclosed herein are environmentally friendly.

As used herein, the term or expression "film" or "barrier layer" refers to thin, partially or substantially plastic and and/or may refer to polymeric materials, including, but not limited to, substrates, bonds, enclosures, barriers, or combinations thereof. Films as described herein may be rigid or flexible, depending on the inherent physical properties or dimensions of their respective compositions. In at least one embodiment, these films or barrier layers can be environmentally friendly or biodegradable.

As used herein, the terms or expressions "enclosure," "barrier," or "water vapor barrier" refer to partially enclosed, fully enclosed, or otherwise Can refer to a material used to prevent moisture, water, or other evaporative materials from entering or exiting through a barrier in a chemical device. In at least one embodiment, these enclosures can be environmentally friendly or biodegradable.

As used herein, the term or expression "metal layer" can refer to a layer of metal on a surface, film, substrate, or barrier layer. The metal layers described herein include metallized coatings that can be deposited on a surface by means of vapor or chemical deposition methods, as well as combined with or adhered to a surface, film, substrate, or barrier layer. Examples of metal layers can be included, including metal foils, metal films, or other metal layers.

In at least one embodiment, the biodegradable electrochemical devices disclosed herein include an anode, a cathode (i.e., a current collector and/or an active layer), and one or more electrolyte compositions (e.g., , a biodegradable solid aqueous electrolyte composition). In another embodiment, the biodegradable electrochemical device comprises one or more substrates, one or more closures, one or more packages, one or more pouches, one or more enclosures. , or a combination thereof.

The biodegradable electrochemical devices disclosed herein can be flexible. As used herein, the term "flexible" refers to a material, device, or component thereof that can be bent around a predetermined radius of curvature without breaking and/or cracking. be able to. The biodegradable electrochemical devices and/or components thereof disclosed herein can be produced around a radius of curvature of about 30 cm or less, about 20 cm or less, about 10 cm or less, about 5 cm or less without breaking or cracking. can be bent to

FIG. 1 illustrates an exploded view of an exemplary biodegradable electrochemical device 100 in a side-by-side or coplanar configuration, according to one or more embodiments. As illustrated in FIG. 1, the biodegradable electrochemical device 100 includes a first substrate 102, a first current collector 104 disposed adjacent to or on the first substrate 102, and a first current collector 104 disposed adjacent to or on the first substrate 102. and a second current collector 106, an anode active layer 108 disposed adjacent to or over the first current collector 104, an anode active layer 108 disposed adjacent to or over the second current collector 106. a second substrate disposed adjacent to or above the cathode active layer 110, the anode active layer 108 and the electrolyte layer 112 disposed adjacent to or above the cathode active layer 110, and the electrolyte composition 112; 114. It should be appreciated that first current collector 104 and anode active layer 108 may be collectively referred to herein as anode 120 of biodegradable electrochemical device 100. It should be further appreciated that second current collector 106 and cathode active layer 110 may be collectively referred to herein as cathode 122 of biodegradable electrochemical device 100. As illustrated in FIG. 1, anode 120 and cathode 122 of biodegradable electrochemical device 100 can be coplanar such that anode 120 and cathode 122 are disposed along the same XY plane.

In at least one embodiment, biodegradable electrochemical device 100 includes current collectors 104, 106, anode active layer 108, cathode active layer 110, and first substrate 102 and first substrate 102. one or more seals capable of or designed to seal or hermetically seal the electrolyte composition 112 (two of which are shown, 116 and 118) between the electrolyte composition 112 and the substrate 114 of the second substrate; ) can be included. For example, as illustrated in FIG. 1, a biodegradable electrical device 100 includes a first substrate 102 and a second substrate to seal or hermetically seal the biodegradable electrochemical device 100. Two seals 116, 118 may be included inserted between the material 114 and around the current collectors 104, 106, the anode active layer 108, the cathode active layer 110, and the electrolyte composition 112. In another embodiment, biodegradable electrochemical device 100 may be free or substantially free of seals 116, 118. For example, substrates 102, 114 may be fused or bonded together to seal biodegradable electrochemical device 100.

FIG. 2 illustrates an exploded view of another exemplary biodegradable electrochemical device 200 in a stacked configuration in accordance with one or more embodiments. As illustrated in FIG. 2, the biodegradable electrochemical device 200 includes a first substrate 202, a first current collector 204 disposed adjacent to or on the first substrate 102. , an anode active layer 208 disposed adjacent to or over the first current collector 204 , an electrolyte layer 212 disposed adjacent to or over the anode 108 , an electrolyte composition 212 adjacent or a cathode active layer 210 disposed thereon, a second current collector 206 disposed adjacent to or on the cathode active layer 210, and a second current collector 206 disposed adjacent to or on the second current collector 206; A second substrate 214 may be disposed thereon. It should be appreciated that first current collector 204 and anode active layer 208 may be collectively referred to herein as anode 220 of biodegradable electrochemical device 200. It should be further appreciated that second current collector 206 and cathode active layer 210 may be collectively referred to herein as cathode 222 of biodegradable electrochemical device 200. As illustrated in FIG. 2, the anode 220 and cathode 222 of the biodegradable electrochemical device 200 are arranged in a stacked configuration or configuration such that the anode 220 and cathode 222 are placed above or below each other. be able to.

In at least one embodiment, the biodegradable electrochemical device 200 includes the current collectors 204, 206, the anode active layer 208, the cathode active layer 210, and the first substrate 202 and the first substrate 202. one or more seals (216, 218 are shown) capable of or designed to hermetically seal the electrolyte composition 212 between the substrate 214 of the ) can be included. For example, as illustrated in FIG. 2, the biodegradable electrical device 200 includes a first substrate 202 and a second substrate 214 to hermetically seal the biodegradable electrochemical device 200. Two seals 216, 218 may be included inserted between and around the current collectors 204, 206, anode active layer 208, cathode active layer 210, and electrolyte composition 212. In another embodiment, biodegradable electrochemical device 200 may be free or substantially free of seals 216, 218. For example, substrates 202, 214 may be fused or bonded together to seal biodegradable electrochemical device 200.

As illustrated in FIGS. 1 and 2, each of the current collectors 104, 106, 204, 206 has a respective Tabs 124, 126, 224, 226 may be included.

In at least one embodiment, any one or more of the substrates 102, 114, 202, 214 of each biodegradable electrochemical device 100, 200 includes, but is not limited to, a biodegradable substrate or may include this. Exemplary biodegradable substrates include, but are not limited to, polylactic acid (PLA), polylactic-co-glycolic acid (PLGA), silk fibroin, chitosan, polycaprolactone (PCL), polyhydroxybutyrate (PHB). , rice paper, cellulose, or a combination or composite thereof.

The biodegradable substrate of each biodegradable electrochemical device 100, 200 can be stable at temperatures from about 50°C to about 150°C. As used herein, the term "stable" or "stable" means resisting dimensional change and maintaining structural integrity when exposed to temperatures of about 50°C to about 150°C. can refer to the ability of a substrate to maintain For example, the biodegradable substrate maintains structural integrity with less than about 20%, less than about 15%, or less than about 10% dimensional change after being exposed to temperatures of about 50°C to about 150°C. or can be designed to be maintained. In one example, each of the biodegradable substrates has a temperature of about 50°C, about 60°C, about 70°C, about 80°C, about 90°C, about 100°C, or about 110°C to about 120°C, about 130°C. , about 140° C., or about 150° C. (eg, less than 20% change in dimensions). In another example, each of the biodegradable substrates is at least 100°C, at least 105°C, at least 110°C, at least 115°C, at least 120°C, at least 125°C, at least 130°C, at least 135°C, at least 140°C, or can be stable at temperatures of at least 145°C. In at least one embodiment, the biodegradable substrate can be stable at temperatures of about 50° C. to about 150° C. for periods of about 5 minutes to about 60 minutes or more. For example, the biodegradable substrate is stable at the temperatures described above for a period of about 5 minutes, about 10 minutes, about 20 minutes, or about 30 minutes to about 40 minutes, about 45 minutes, about 50 minutes, about 60 minutes or more. I can do what I do.

In at least one embodiment, the biodegradable substrate is weldable, bondable, and/or permanently heat sealable without the use of additional adhesives. For example, each biodegradable substrate of substrates 102, 114, 202, 214 may be weldable and/or bondable to each other without the use of respective closures 116, 118, 216, 218. Can be done. Exemplary biodegradable substrates that may be weldable and/or bondable to each other include, but are not limited to, thermoplastics, such as polylactic acid (PLA), modified with nucleating agents to enhance crystallinity. Polylactic acid, such as polylactic acid modified with nucleating agent D (PLA-D) and polylactic acid modified with nucleating agent E (PLA-E), polybutylene succinate (PBS), polybutylene adipate terephthalate (PBAT), It may be or include a blend of PLA and polyhydroxybutyrate (PHB), a PHB-based blend, etc., or a combination thereof. As used herein, the terms or expressions "bondable," "weldable," and/or "permanently thermally sealable" refer to heating or melting two surfaces together. Can refer to the ability of a material (eg, a substrate) to seal or permanently connect two surfaces together.

The anode active layer 108, 208 of each biodegradable electrochemical device 100, 200 includes, but is not limited to, zinc (Zn), lithium (Li), carbon (C), cadmium (Cd), nickel (Ni). , magnesium (Mg), a magnesium alloy, a zinc alloy, etc., or a combination and/or alloy thereof, or may contain these. Exemplary anode active layers or materials thereof may include, but are not limited to, or combinations thereof. In at least one embodiment, the anode active layer can include zinc oxide (ZnO) in an amount sufficient to modulate or control H2 gas generation.

In at least one embodiment, the anode active layer 108, 208 of each biodegradable electrochemical device 100, 200 can be prepared or fabricated from an anode paste. For example, the anode active layer can be prepared from a zinc anode paste. The anode paste can be prepared in an attriter mill. In at least one embodiment, stainless steel shot can be placed in an attritor mill to facilitate preparation of the anode paste. The anode paste agent can include one or more metals or metal alloys, one or more organic solvents, one or more styrene-butadiene rubber binders, or combinations thereof. In an exemplary embodiment, the anode paste agent comprises one or more of ethylene glycol, styrene-butadiene rubber binder, zinc oxide (ZnO), bismuth(III) oxide (Bi ₂ O ₃ ), Zn dust, or a combination thereof. Exemplary organic solvents are known in the art and may include, but are not limited to, ethylene glycol, acetone, NMP, etc., or combinations thereof. In at least one embodiment, any one or more biodegradable binders can be utilized in place of or in combination with the styrene-butadiene rubber binder.

The cathode active layers 110, 210 of the biodegradable electrochemical devices 100, 200, respectively, include, but are not limited to, iron (Fe), iron (VI) chloride, mercury oxide (HgO), manganese (IV) oxide (MnO ₂ ), carbon (C), carbon-containing cathode, gold (Au), molybdenum (Mo), tungsten (W), molybdenum trioxide (MoO ₃ ), silver oxide (Ag ₂ O), copper (Cu), vanadium oxide (V ₂ O ₅ ), nickel oxide (NiO), copper iodide (Cu ₂ I ₂ ), copper chloride (CuCl), etc., or a combination and/or alloy thereof. or may include these. In an exemplary embodiment, the cathode active layer 110, 210 may include manganese (IV) oxide. Carbon and/or carbon-containing cathode active layers can be utilized in aqueous metal-air cells, such as zinc-air cells.

In at least one embodiment, the cathode active layer 110, 210 includes one or more additives capable of or designed to at least partially enhance the electronic conductivity of the cathode active layer 110, 210. can include. Exemplary additives may be or include carbon particles, such as, but not limited to, graphite, carbon nanotubes, carbon black, etc., or combinations thereof.

In at least one embodiment, the cathode active layer 110, 210 of each biodegradable electrochemical device 100, 200 can be prepared or fabricated from a cathode paste. For example, cathode active layers 110, 210 can be prepared from manganese (IV) oxide cathode paste. The cathode paste can be prepared in an attriter mill. In at least one embodiment, stainless steel shot can be placed in an attritor mill to facilitate cathode paste preparation. The cathode paste can include one or more metals or metal alloys, one or more organic solvents (e.g., ethylene glycol), one or more styrene-butadiene rubber binders, or combinations thereof. . In an exemplary embodiment, the cathode paste can include one or more of ethylene glycol, a styrene-butadiene rubber binder, manganese (IV) oxide (MnO ₂ ), graphite, or a combination thereof. . Exemplary organic solvents are known in the art and may include, but are not limited to, ethylene glycol, acetone, NMP, etc., or combinations thereof. In at least one embodiment, one or more organic solvents may be replaced with or used in combination with an aqueous solvent, such as water. For example, water can be utilized in combination with manganese (IV) oxide.

The anode and/or cathode paste may have a viscosity of about 100 cP to about 1E6 cP. For example, the anode and/or cathode paste may be about 100 cP or more, about 200 cP or more, about 500 cP or more, about 1,000 cP or more, about 1,500 cP or more, about 2,000 cP or more, about 10,000 cP or more, about 20, 000cP or more, about 50,000cP or more, about 1E5cP or more, about 1.5E5cP or more, about 2E5cP or more, about 3E5cP or more, about 4E5cP or more, about 5E5cP or more, about 6E5cP or more, about 7E5cP or more, about 8E5cP or more, or about 9E5cP It may have a viscosity higher than that. In another example, the anode and/or cathode paste is about 200 cP or less, about 500 cP or less, about 1,000 cP or less, about 1,500 cP or less, about 2,000 cP or less, about 10,000 cP or less, about 20,000 cP or less. Below, about 50,000cP or less, about 1E5cP or less, about 1.5E5cP or less, about 2E5cP or less, about 3E5cP or less, about 4E5cP or less, about 5E5cP or less, about 6E5cP or less, about 7E5cP or less, about 8E5cP or less, about 9E5cP or less, Or it may have a viscosity of about 1E6 cP or less.

In at least one embodiment, each of the anodes 120, 220 and cathodes 122, 222 or their active layers 108, 110, 208, 210 can independently include a biodegradable binder. The function of the biodegradable binder is to anchor the respective particles of each layer together, providing adhesion to the subsurface of the substrate; a current collector 106, 206, an anode active layer 108, 208, a cathode active layer 110, 210, or a combination thereof. Exemplary biodegradable binders include, but are not limited to, one of chitosan, polylactic-co-glycolic acid (PLGA), gelatin, xanthan gum, cellulose acetate butyrate (CAB), polyhydroxybutyrate (PHB). It may be or include species or species or combinations thereof. In at least one embodiment, any one or more of the biodegradable polymers disclosed herein with respect to the electrolyte composition is also used in the anode 120, 220, the cathode 122, 222, a component thereof, or Any combination of these can also be used as a biodegradable binder. Further, as described herein, one or more biodegradable polymers may be crosslinked. Thus, the biodegradable binders utilized in the anodes 120, 220, cathodes 122, 222, and/or components thereof include the crosslinked biodegradable binders disclosed herein with respect to the electrolyte compositions. be able to.

The respective electrolyte layer 112, 212 of the respective biodegradable electrochemical device 100, 200 may be or include an electrolyte composition. The electrolyte composition can utilize biodegradable polymeric materials. The electrolyte composition may be a solid, aqueous electrolyte composition. The solid, aqueous electrolyte composition may include or include a copolymer hydrogel as well as a salt dispersed in and/or throughout the hydrogel. The copolymer can include at least two polycaprolactone (PCL) chains attached to a polymer central block (CB). For example, the copolymer may be a block copolymer or a graft copolymer comprising at least two PCL chains coupled to a central block of the polymer, such as PCL-CB-PCL. In another example, the copolymer includes a block comprising at least one of polylactic acid (PLA), polyglycolic acid (PGA), polyethyleneimine (PEI), or combinations thereof, coupled to a central block of the polymer. It may be a copolymer or a graft copolymer.

The copolymer or solid can be present in the hydrogel in an amount from about 5% to about 90% by weight, based on the total weight of the hydrogel (eg, the total weight of solvent, polymer, and salt). For example, the copolymer may be present in an amount of about 5% or more, 10% or more, 15% or more, 20% or more, 25% or more, 30% or more, 35% or more by weight based on the total weight of the hydrogel. It can exist in In another example, the copolymer may be present in an amount of 90% or less, 80% or less, 70% or less, or 60% by weight or less, based on the total weight of the hydrogel. In preferred embodiments, the copolymer or solid is present in the hydrogel at about 5% to about 60%, about 5% to about 50%, about 20% to about 40% by weight, based on the total weight of the hydrogel. , or in an amount of about 30% by weight. In yet another preferred embodiment, the copolymer or solid may be present in the hydrogel in an amount of greater than 30% to 60% by weight, based on the total weight of the hydrogel.

The copolymer may be present in the hydrogel in an amount sufficient to provide a continuous film or layer that is free or substantially free of air bubbles. The copolymer may also be present in the hydrogel in an amount sufficient to provide a viscosity of about 1,000 cP to about 100,000 cP. For example, the copolymer may be present in the hydrogel at about 1,000 cP, about 5,000 cP, about 10,000 cP, or about 20,000 cP to about 30,000 cP, about 40,000 cP, about 50,000 cP, about 75,000 cP, about It may be present in an amount sufficient to provide a viscosity of 90,000 cP, or about 100,000 cP.

The polymeric core block of the copolymer may be a biodegradable polymer, thereby improving or increasing the biodegradability of the solid, aqueous electrolyte composition. The biodegradable polymer of the polymeric center block is preferably naturally occurring. The central block of the polymer may be or may include or be derived from a polymer, such as a biodegradable polymer containing at least two free hydroxyl groups available for reaction with ε-caprolactone. may be done. As further described herein, polymers containing at least two free hydroxyl groups can be reacted with ε-caprolactone to form a copolymer. Exemplary polymers containing at least two free hydroxyl groups that can be utilized to form the polymeric central block (CB) include, but are not limited to, polyvinyl alcohol (PVA), hydroxyl-bearing polysaccharides, biodegradable It may be or include one or more of polyesters, hydroxy fatty acids (eg, castor oil), or combinations thereof. Exemplary hydroxyl-bearing polysaccharides include, but are not limited to, starch, cellulose, carboxymethylcellulose, methylcellulose, hydroxyethylcellulose, chitin, guar gum, xanthan gum, agar, pullulan, amylose, alginic acid, dextran, etc., or combinations thereof. or may include these. Exemplary biodegradable polyesters may be, but are not limited to, polylactic acid, polyglycolic acid, polylactic-co-glycolic acid, polyitaconic acid, polybutylene succinate, etc., or combinations thereof; Or it may contain these. In preferred embodiments, the polymeric center block may be or include one or more of polyvinyl alcohol (PVA), a hydroxyl-bearing polysaccharide, a biodegradable polyester, or a hydroxy fatty acid. .

In at least one embodiment, the polymer center block of the copolymer may not be a biodegradable polymer. For example, the polymer center block of the copolymer may be, but is not limited to, polyethylene glycol (PEG), hydroxy-terminated polyester, hydroxy-terminated polyolefin, such as hydroxy-terminated polybutadiene, or combinations thereof. May include.

A copolymer comprising at least two polycaprolactone (PCL) chains attached to a polymeric central block may be a graft copolymer or a block copolymer. Whether a copolymer is a graft copolymer or a block copolymer may be determined at least in part by the number and/or arrangement of at least two free hydroxyl groups on the polymer center block. For example, when ε-caprolactone is reacted with a polymer center block having hydroxyl groups on the monomer along the length of the polymer center block chain, a graft copolymer is formed. In another example, a block copolymer is formed when ε-caprolactone is reacted with a polymeric center block having each of the hydroxyl groups at each end of the polymeric center block. Exemplary block copolymers may be or include triblock copolymers, tetrablock copolymers, star block copolymers, or combinations thereof.

As discussed above, the electrolyte composition can be a solid, aqueous electrolyte composition comprising a copolymer hydrogel and a salt dispersed within the hydrogel. The hydrogel salt may be or include any suitable ionic salt known in the art. Exemplary ionic salts include, but are not limited to, one or more of organic-based salts, inorganic-based salts, room temperature ionic liquids, deep eutectic solvent-based salts, or combinations thereof. It may be a mixture or may contain these. In a preferred embodiment, the salt is or comprises a salt usable in zinc/manganese(IV) oxide (Zn/ _MnO2 ) electrochemistry. Exemplary salts include, but are not limited to, zinc chloride _{( ZnCl2} ), ammonium chloride ( _NH4Cl ), sodium chloride (NaCl), phosphate buffered saline (PBS), sodium sulfate ( _Na2SO4 ), Zinc sulfate (ZnSO ₄ ), manganese sulfate (MnSO ₄ ), magnesium chloride (MgCl ₂ ), calcium chloride (CaCl _{2 ), ferric chloride (FeCl 3 )} , lithium hexafluorophosphate (LiPF ₆ ), potassium hydroxide (KOH), sodium hydroxide (NaOH), etc., or a combination thereof. In preferred embodiments, the salt of the electrolyte composition may be or include ammonium chloride (NH ₄ Cl), zinc chloride (ZnCl ₂ ), or a combination or mixture thereof. In another embodiment, the salt may be an alkali metal salt, such as sodium hydroxide (NaOH), ammonium hydroxide ( _NH4OH ), potassium hydroxide (KOH), or combinations or mixtures thereof. , or may include these.

The salt may be present in an amount possible to provide ionic conductivity, in an amount designed to provide ionic conductivity, or in an amount sufficient to provide ionic conductivity. For example, the salt may be present in the hydrogel in an amount or concentration of at least 0.1M, more preferably at least 0.5M, even more preferably at least 2M, even more preferably at least 4M. The salt may be present in the hydrogel at a concentration of 10M or less, more preferably 6M or less. In another example, the salt may be present in the hydrogel in an amount of about 3M to about 10M, about 4M to about 10M, about 5M to about 9M, or about 6M to about 8M. In an exemplary implementation, the salts included ammonium chloride and zinc chloride. In this case, ammonium chloride is present in an amount of about 2.5M to about 3M, about 2.8M to about 2.9M, or about 2.89M, and zinc chloride is present in an amount of about 0.5M to about 1.5M, about 0. Present in an amount of 8M to about 1.2M, or about 0.9M.

In at least one embodiment, the electrolyte composition can include one or more additives. The one or more additives may be or include, but are not limited to, biodegradable or environmentally friendly nanomaterials. The biodegradable nanomaterial may be capable of providing and/or improving the structural strength of the electrolyte layer or its electrolyte composition without sacrificing the flexibility of the electrolyte layer or its electrolyte composition. or may be designed to do so. Exemplary biodegradable nanomaterials for additives may be or include, but are not limited to, polysaccharide-based nanomaterials, inorganic nanomaterials, etc., or combinations thereof. Exemplary polysaccharide-based nanomaterials may be one or more of, but are not limited to, cellulose nanocrystals, chitin nanocrystals, chitosan nanocrystals, starch nanocrystals, etc., or combinations or mixtures thereof; Or it may contain these. Exemplary inorganic nanomaterials may be, but are not limited to, one or more of silicon oxide (e.g., fumed silica), aluminum oxide, layered silicates, or lime, or combinations or mixtures thereof. , or may include these. Exemplary layered silicates include, but are not limited to, bentonite, kaolinite, dickite, nacrite, attapulgite, illite, halloysite, montmorillonite, hectorite, fluorohectolite, nontronite, beidellite, saponite, volkonscoreite, May be or contain one or more of magadiite, medmontite, kenyaite, sauconite, muscovite, vermiculite, mica, hydromica, phengite, bramarite, celadonite, or combinations or mixtures thereof. But that's fine.

One or more additives may be present in an amount of at least 0.1% by weight, based on the total weight of the hydrogel. For example, the one or more additives may be present in an amount of at least 0.1%, at least 0.5%, or at least 1% by weight, based on the total weight of the hydrogel. One or more additives may also be present in an amount up to 40% by weight, based on the total weight of the hydrogel. For example, the one or more additives may be present in an amount of 40% or less, 20% or less, or 10% or less, based on the total weight of the hydrogel.

In at least one embodiment, the electrolyte composition can include an aqueous solvent. For example, the electrolyte composition can include water. In at least one embodiment, the electrolyte composition can include a co-solvent. For example, the electrolyte composition can include water and an additional solvent. Exemplary cosolvents may be or include, but are not limited to, one or more of ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, or combinations thereof. The co-solvent is greater than about 20%, greater than about 30%, greater than about 40%, greater than about 50% to greater than about 60%, greater than about 70%, greater than about 80% of the total weight or volume of the aqueous solvent of the electrolyte composition. , greater than about 85%, or greater than about 90% water.

In at least one embodiment, the electrolyte composition comprises a copolymer hydrogel and a salt dispersed in the hydrogel, a solvent (e.g., water or water and a cosolvent), one or more photoinitiators, an optional one or more or a combination thereof. For example, the electrolyte composition includes a copolymer hydrogel, a salt dispersed within the hydrogel, a solvent, one or more additives, or a combination or mixture thereof. In at least one embodiment, the electrolyte composition consists of or consists essentially of a copolymer hydrogel, a salt dispersed within the hydrogel, and a solvent (eg, water or water and a cosolvent). In another embodiment, the electrolyte composition consists of or consists essentially of a copolymer hydrogel, a salt dispersed within the hydrogel, a solvent, and one or more additives. The solvent, which may be water or a combination of water and a co-solvent, can provide an equilibrium state for the hydrogel. Suitable electrolyte compositions and methods and procedures for producing the same are disclosed in International Application PCT/US2020/046932, the disclosure of which is hereby incorporated by reference in its entirety. .

As previously discussed, each electrolyte layer 112, 212 of the biodegradable electrochemical device 100, 200 may be or include a solid, aqueous electrolyte composition. The solid, aqueous electrolyte composition can have sufficient mechanical and electrochemical properties required for commercially available printed cells or commercially useful printed cells. For example, the solid, aqueous electrolyte composition can have a Young's modulus or storage modulus of greater than about 0.10 megapascals (MPa), greater than about 0.15 MPa, or greater than about 0.20 MPa, thus stressing To provide a solid, aqueous electrolyte composition that has sufficient strength while maintaining sufficient flexibility to prevent breakage under conditions. The solid, aqueous electrolyte composition can have a Young's modulus of about 100 MPa or less, about 80 MPa or less, about 60 MPa or less, or less.

As used herein, the term or expression "yield strength" may refer to the maximum stress that a material undergoes or can sustain before it begins to permanently deform. The solid, aqueous electrolyte composition can have a yield strength of about 5 kPa or more. For example, the solid, aqueous electrolyte composition can have a yield strength of about 5 kPa or more, about 8 kPa or more, about 10 kPa or more, about 12 kPa or more, about 15 kPa or more, or about 20 kPa or more.

The solid, aqueous electrolyte composition can be electrochemically stable to both the anode active layer 108, 208 and cathode active layer 110, 210 of the biodegradable electrochemical device 100, 200, respectively. For example, the solid, aqueous electrolyte composition can maintain a stable no-load voltage over long periods of time, thereby providing an effective solution to the anode active layer 108, 208 and cathode active layer of the biodegradable electrochemical device 100, 200, respectively. Demonstrates electrochemical stability for both 110 and 210. In at least one embodiment, the solid, aqueous electrolyte composition is used for at least 1 month, at least 2 months, at least 3 months, at least 4 months, at least 5 months, at least 6 months, at least 1 year, or longer. It can be electrochemically stable in contact with the electrode layer.

The solid, aqueous electrolyte compositions disclosed herein can be used in any electrochemical device, such as an electrochemical cell, a battery, and/or a biodegradable electrochemical device 100, 200 as disclosed herein. It can be used in In a preferred embodiment, a solid, aqueous electrolyte composition can be utilized in a cell that includes a Zn anode active layer and a MnO ₂ cathode active layer.

The current collectors 104, 106, 204, 206 of each biodegradable electrochemical device 100, 200 may be capable of, or designed to receive, conduct, and deliver electricity. You can leave it there. Exemplary current collectors 104, 106, 204, 206 include, but are not limited to, silver, e.g., silver microparticles and silver nanoparticles, carbon, e.g., carbon black, graphite, carbon fibers, carbon nanoparticles, e.g. It may be or include carbon nanotubes, graphene, reduced graphene oxide (RGO), etc., or any combination thereof.

Methods Embodiments of the present disclosure can provide methods for fabricating electrochemical devices, such as the biodegradable electrochemical devices 100, 200 disclosed herein. The method can include providing a biodegradable substrate. The method can also include depositing an electrode and/or electrode composition adjacent to or on the biodegradable substrate. Depositing the electrode may include depositing and drying a current collector of the electrode and depositing and drying an active layer (i.e., an anode or cathode material) adjacent to or on the current collector. Can be done. The method can also include drying the electrode and/or electrode composition. The electrode composition may be dried thermally (eg, by heating). The method can also include depositing a biodegradable, radiation-curable electrolyte composition on or adjacent to the electrode composition. The method can further include radiation curing the biodegradable radiation curable electrolyte composition. The biodegradable radiation-curable electrolyte composition can be cured by radiation before or after drying the electrode composition. The biodegradable substrate may be thermally compatible with any thermal drying. For example, a biodegradable substrate can be dimensionally stable (eg, free of bowing and/or curling) when thermally dried. The method can include depositing a second electrode and/or electrode composition over or adjacent to the biodegradable, radiation-curable electrolyte composition. In at least one embodiment, each of the first and second electrode compositions is a metal foil composition. The metal foil composition of the first electrode may be different from the metal foil composition of the second electrode.

In at least one embodiment, the electrochemical device, all of its components, or substantially all of its components, are fabricated via a printing process. Printing processes can include depositing, stamping, spraying, sputtering, jetting, coating, layering, and the like. For example, one or more current collectors, one or more electrode compositions, biodegradable, radiation-curable electrolyte compositions, or combinations thereof can be deposited via a printing process. Exemplary printing processes include, but are not limited to, one or more of screen printing, inkjet printing, flexography (e.g., stamping), gravure printing, offset printing, airbrushing, aerosol printing, typesetting, roll-to-roll printing, and the like. It may be a plurality, or a combination thereof, or may include a plurality of them. In a preferred embodiment, the components of the electrochemical device are printed via screen printing.

In at least one embodiment, radiation curing the biodegradable radiation curable electrolyte composition includes exposing the electrolyte composition to radiant energy. The radiant energy may be ultraviolet light. By exposing the biodegradable radiation-curable electrolyte composition to radiant energy, the biodegradable radiation-curable electrolyte composition can be at least partially crosslinked, thereby forming a hydrogel. The biodegradable radiation-curable electrolyte composition can be cured by radiation at room temperature. In at least one embodiment, the biodegradable radiation-curable electrolyte composition is cured in an inert atmosphere. For example, the biodegradable radiation-curable electrolyte composition can be cured under nitrogen, under argon, and the like. In another embodiment, the biodegradable radiation-curable electrolyte composition may be cured under a non-inert atmosphere.

In at least one embodiment, the biodegradable radiation-curable electrolyte composition can be radiation-cured for a period of about 5 ms to about 100 ms. For example, the biodegradable radiation curable electrolyte composition can be used for about 5 ms, about 10 ms, about 15 ms, about 20 ms, about 30 ms, about 40 ms, or about 50 ms to about 60 ms, about 70 ms, about 80 ms, about 85 ms, about 90 ms, It can be cured by radiation for a period of about 95 ms, or about 100 ms. The period of time sufficient to radiation cure the biodegradable radiation curable electrolyte composition can be determined at least in part by the output of the ultraviolet light.

In at least one embodiment, the method also includes depositing an adhesive, such as a biodegradable adhesive, thereby sealing each seal 116, 118, 216, 218 of the biodegradable electrochemical device 100, 200. It may also include the step of obtaining. For example, the method includes depositing a layer of adhesive to couple the substrate or portions of the substrate of the electrochemical device (e.g., the peripheral areas of the tabs 124, 126, 224, 226) to each other. be able to. In some embodiments, the adhesive may be a hot melt adhesive. In another embodiment, the electrochemical device may be free or substantially free of any adhesive. For example, the biodegradable substrate can be weldable and/or heat sealable without the use of additional adhesives.

In at least one embodiment, the biodegradable substrate may be or be supported by a continuous web. As used herein, the term "web" can refer to a moving support surface, such as a conveyor belt. In at least one example, multiple electrochemical devices are printed simultaneously as separate or connected elements or components on a continuous web. For example, each component of a plurality of electrochemical devices can be printed simultaneously as an array in a parallel process, as independent or connected components on a continuous web. As used herein, the term or expression "linked elements" or "linked components" refers to electrochemical components that are physically adjacent, overlapping, or otherwise in contact with each other. Can refer to each element or component of a device. Exemplary coupled elements include an active layer (e.g., a cathode active layer or an anode active layer) disposed adjacent to or over a current collector layer, a current collector layer and a copper tape tab, or an active cathode/ It may be or include an electrolyte layer on top of the anode layer.

In at least one embodiment of an exemplary biodegradable electrochemical device, the solid aqueous electrolyte and methods of synthesizing and fabricating the same are available, including current collectors, cathode/anode materials, binders, adhesives, Layers of various materials, including and electrolytes, need to be printed with high fidelity and precision. Additionally, water retention within the aqueous electrolyte is critical to battery performance through the maintenance of solubilized salts for good ionic conductivity, such as biodegradable or compostable printed batteries. suffer from reduced lifetime due to moisture loss through evaporation through the biodegradable substrate, which may be a polylactic acid (PLA) film. Such electrochemical devices can have a biodegradable polymer composite film enclosure pouch with a biodegradable barrier layer. Exemplary biodegradable enclosure materials include, but are not limited to, polylactic acid (PLA), polylactic-co-glycolic acid (PLGA), silk fibroin, chitosan, polycaprolactone (PCL), polyhydroxybutyrate (PHB). , rice paper, cellulose, or a combination or composite thereof.

In at least one embodiment, a flexible material comprising an anode, a cathode, and an electrolyte composition comprising a crosslinked biodegradable polymeric material that is crosslinked between the anode and cathode and is radiation curable prior to printing. Some biodegradable electrochemical devices contain biodegradable moisture that forms an enclosure, film or pouch around the outer portion of the electrochemical device to prevent the moisture present within the aqueous electrolyte material from evaporating. Or it can have a water vapor barrier or barrier layer. In such embodiments, the entire electrochemical device is biodegradable, so the device can have a long service life due to improved properties of the water vapor barrier or moisture barrier layer of the enclosure pouch, and the biodegradable and/or may be biodegradable at the end of its useful life. The function of the biodegradable water vapor barrier or enclosure is to provide a moisture barrier layer that prevents water from evaporating from the aqueous electrolyte composition within the electrochemical device, thus extending the useful life of the electrochemical device. In connection with the water vapor barrier or moisture barrier layers described herein, certain embodiments of electrochemical devices can have significant amounts of water or moisture, while other solvents or evaporative It is noted that chemical materials can also aid in long-term and acceptable operation of electrochemical devices encapsulated within the water vapor barrier of the present disclosure.

The biodegradable water vapor barrier of each biodegradable electrochemical device can be stable at temperatures from about 50°C to about 150°C. As used herein, the term "stable" or "stable" means resisting dimensional change and maintaining structural integrity when exposed to temperatures of about 50°C to about 150°C. can refer to the ability of a substrate to maintain For example, a biodegradable water vapor barrier may lose its structural integrity with a dimensional change of less than about 20%, less than about 15%, or less than about 10% after being exposed to a temperature of about 50°C to about 150°C. can be maintained or designed to be maintained. In one example, each of the biodegradable water vapor barriers has a temperature of about 50°C, about 60°C, about 70°C, about 80°C, about 90°C, about 100°C, or about 110°C to about 120°C, about 130°C. , about 140° C., or about 150° C. (eg, less than 20% change in dimensions). In another example, each of the biodegradable water vapor barriers includes at least 100°C, at least 105°C, at least 110°C, at least 115°C, at least 120°C, at least 125°C, at least 130°C, at least 135°C, at least 140°C, or can be stable at temperatures of at least 145°C. In at least one embodiment, the biodegradable water vapor barrier can be stable at temperatures of about 50° C. to about 150° C. for periods of about 5 minutes to about 60 minutes or more. For example, the biodegradable water vapor barrier is stable at the temperatures described above for a period of about 5 minutes, about 10 minutes, about 20 minutes, or about 30 minutes to about 40 minutes, about 45 minutes, about 50 minutes, about 60 minutes or more. I can do what I do.

In at least one embodiment, the biodegradable water vapor barrier material is weldable, bondable, and/or permanently thermally sealable without the use of additional adhesives. For example, the biodegradable water vapor barriers described herein for electrochemical device enclosures can be welded and/or bonded together without the use of respective seals. Exemplary biodegradable water vapor barrier materials that may be weldable and/or bondable to each other include, but are not limited to, thermoplastics, such as polylactic acid (PLA), modified with nucleating agents to enhance crystallinity. Polylactic acid modified with nucleating agent D (PLA-D) and polylactic acid modified with nucleating agent E (PLA-E), polybutylene succinate (PBS), polybutylene adipate terephthalate (PBAT) , a blend of PLA and polyhydroxybutyrate (PHB), a PHB-based blend, etc., or a combination thereof. As used herein, the terms or expressions "bondable," "weldable," and/or "permanently thermally sealable" refer to heat-sealing two surfaces together through heating or melting. can refer to the ability of a material (eg, a substrate) to bind or permanently connect two surfaces together.

In some embodiments, the biodegradable enclosure, pouch, or water vapor barrier can be made from a metallized biodegradable polylactic acid (PLA) film, such as an aluminum metallized polylactic acid film. The metal surface layer providing metallization may be aluminum. In certain embodiments, the metallized layer can include aluminum, other suitable metals or alloys, ceramics, clays, inorganic-organic biopolymer hybrid materials, and combinations thereof. Alternative embodiments can have metal multilayers, metals on the inner layer, outer layer, or both of the multilayer film. The PLA film can be biaxially oriented to improve the physical properties of the enclosure pouch. In yet other embodiments, additives may be incorporated into the film to enhance moisture barrier properties. A biodegradable enclosure, pouch, or water vapor barrier for an electrochemical device can have a single layer or multiple layers with a combination of one or more materials in alternative embodiments. The metallized layer film or barrier can provide a thickness of about 1 nm to about 100 nm, about 5 nm to about 50 nm, or about 10 nm to about 40 nm. Certain example monolayer films or barriers can have a total thickness of about 1 μm to about 100 μm, about 40 μm to about 80 μm, or about 50 μm to about 75 μm. The metallized layer of the water vapor barrier can have a thickness of about 0.5 nm to about 100 nm, about 5 nm to about 50 nm, or about 5 nm to about 25 nm on the base film layer, eg, PLA.

In certain instances, the biodegradable enclosure, pouch, or water vapor barrier is a multilayer composite constructed by extruding or laminating a biodegradable polymer onto each side of a thin metal foil, e.g., aluminum. You may be able to do it. In contrast to the metallized polymer layers of biodegradable enclosures, the thin and continuous metal layers in such multilayered laminate composites have strong A barrier layer can be provided. The advantage of such a multilayered laminate structure is that a continuous metal film forms a layer that can more effectively prevent water permeation through the composite, as well as a thicker metal or It is to offer the option of providing an aluminum layer or a metal multilayer. Thus, the metal layer that provides a water vapor barrier can be from about 1 μm to about 200 μm, or from about 5 μm to about 150 μm, or from about 10 μm to about 100 μm. Metal foil layers according to the present disclosure do not suffer from problems such as pinholes in aluminum or metal layers (which are common in metal films formed from sputtering or other deposition methods such as those described herein). There is not much tendency to cause it. The presence of pinholes in the metal or other barrier layer within the biodegradable enclosure, pouch, or water vapor barrier may in some cases allow some water to permeate through the composite material.

For certain examples with multilayer composites according to the present disclosure, several methods can be used to form these multilayer laminates. In a first embodiment, the pre-existing polymer sheet uses one or more interdigitated or dispersed adhesive bonding layers that enable or enhance the adhesion of this polymer sheet to the aluminum or metal foil. can be pressed onto one or each side of the aluminum sheet at the appropriate temperature and pressure. In a second embodiment, the polymer layer and adhesive tie layer can be melt extruded as a thin film directly onto the surface of an aluminum or other metal foil using multilayer film casting methods known to those skilled in the art. can. Additional metal foils or films incorporating metals such as magnesium, titanium, iron, nickel, copper, zinc, or alloys or mixtures thereof can be used in accordance with the present disclosure.

In certain embodiments, other materials known to have water vapor barrier properties can be used. These materials must be compatible with biodegradable and/or compostable formats and include materials such as beeswax, plasticizers, and alternative biodegradable polymer composite films. In alternative embodiments where the water vapor barrier is not part of the substrate of the electrochemical device, higher temperature stability and A resistant water vapor barrier can be used. Embodiments of electrochemical devices with biodegradable enclosures or water vapor barriers with moisture barrier properties have lower water vapor transmission rates (WVTR) when compared to electrochemical devices without such barriers, layers, or enclosures. ), from about 0% over 24 hours to about 5% over 24 hours, from about 0.1% over 24 hours to about 2% over 24 hours, or from about 0.5% over 24 hours to about 2% over 24 hours. It shows a WVTR of about 1%. WVTR can also be expressed as a percentage of the total mass of water lost compared to the total mass of the electrochemical device including the enclosure or moisture barrier. Embodiments of electrochemical devices with biodegradable enclosures or water vapor barriers with moisture barrier properties according to the present disclosure have lower water vapor permeability ( WVTR), and the water vapor barrier is about 0.0 g/m ² /24 hours to about 10 g/m ² /24 hours, about 0.5 g/m ² /24 hours to about 5 g/m ² /24 hours, or from about 1 g/m ² /24 hours to about 2 g/m ² /24 hours. Expressions of WVTR are provided herein as mass percent of the total electrochemical device, or mass %. Certain examples of electrochemical devices with biodegradable enclosures or water vapor barriers with moisture barrier properties have lower water vapor transmission rates (WVTR) when compared to electrochemical devices without such barrier layers or enclosures. ), and the water vapor barrier of the present disclosure can exhibit from about 0 mg/cm ² /24 hours to about 5.0 mg/cm ² /24 hours, from about 0.1 mg/cm ² /24 hours to about 1 mg/cm ² /24 hours, or from about 0.1 mg/cm ² /24 hours to about 0.5 mg/cm ² /24 hours.

In some embodiments, the electrochemical device may be arranged such that the battery or electrochemical device is completely contained within an enclosure or within a described water vapor barrier having improved water vapor barrier properties. Often, the cathode and anode may be oriented or arranged in a side-by-side or lateral XY plane configuration as illustrated in FIG. In an alternative embodiment, the electrochemical device may be arranged such that the battery or electrochemical device is contained within the described enclosure having improved water vapor barrier properties, with the cathode and anode as shown in FIG. may be oriented or arranged in a stacked configuration as shown in FIG.

Embodiments of the present disclosure can provide methods for fabricating, producing, or otherwise encapsulating electrochemical devices with improved moisture or water vapor barrier properties. The method comprises forming a first metallized PLA film having four edges and a second metallized PLA film having four edges such that the non-metallized side of the first metalized PLA film is connected to the second metallized PLA film. Orienting the film toward the non-metallized side. One or more edges of the first and second metalized PLA films can also be sealed together. The biodegradable or compostable electrochemical device is placed between the first metalized PLA film and the second metalized PLA film, followed by the edges of the first metalized PLA film and the second metalized PLA film. The edges of the second metalized PLA film can be sealed together such that one or more electrodes of the electrochemical device are exposed through at least one of the four edges.

The method may alternatively include orienting a first metalized PLA film having four edges on top of the electrochemical device, with the non-metallized side facing the electrochemical device. The second metallized PLA film is oriented toward the bottom side of the electrochemical device, with the non-metallized side facing the electrochemical device. All four edges of the first metalized PLA film and four edges of the second metalized PLA film are arranged such that one or more electrodes are exposed through at least one of the four edges. They can also be sealed together. Enclosures or water vapor barriers fabricated in this manner from biodegradable aluminized polymeric barrier layers can be combined with surface coatings and/or polymeric additives to reduce water vapor loss from biodegradable or compostable electrochemical devices. can be reduced or prevented. Such devices can significantly extend the useful life of biodegradable or compostable electrochemical devices by preventing evaporation of the electrolyte solvent over time.

The examples and other implementations described herein are illustrative and are not intended to limit the description of the full scope of the compositions and methods of the present disclosure. Equivalent changes, modifications, and variations of specific implementations, materials, compositions, and methods can be made within the scope of this disclosure and produce substantially similar results.

(Comparative example 1)
A surrogate test is described in connection with Comparative Example 1, related to the embodiments described herein of biodegradable battery configurations with improved moisture retention. FIG. 3 illustrates a cross-sectional view of a comparative example of a fully assembled alternative to a biodegradable battery assembly with a water vapor barrier in accordance with one or more embodiments. This surrogate test was conducted to measure water loss through the PLA-D biodegradable substrate under conditions similar to a fully assembled biodegradable battery. Comparative Example 1 is a replacement battery assembly 300 having a film enclosure 304 surrounding a patch of filter paper 302 as a replacement for an aqueous electrolyte battery composition. Two sheets of 80 μm thick biaxially stretched film of PLA-D were cut into 2 cm x 3 cm squares. Two pieces of cut film were laminated together in the same orientation. Heat seal three of the four edges of the film sheet together using an MTI MSK-130 heat sealing device set to 170°C for 5 seconds to form a single, unsealed 3 cm produced a pouch or enclosure with sides of . A 1 cm square patch of whatman 1825-150 filter paper 302 was placed in a 2 cm x 3 cm pouch 304. The pouch with filter paper 302 inside was then weighed and tared. Three drops of DI water were added to the paper within the pouch and the remaining open edge of the pouch was then sealed to form a heat sealed edge 306 under the same conditions as previously described. The mass of the pouch was measured over time to determine water loss. The surrogate test involves the creation of a fully sized, sealed substrate configuration, containing a known, measured amount of water that reflects the same amount found in a fully assembled biodegradable battery. Added. Next, water loss over time is measured by periodically weighing the substitute battery assembly 300. This test protocol was then repeated using Experimental Examples 1-3 to test a variety of film enclosures for inhibiting water permeation losses from aqueous-based electrolyte compositions within biodegradable electrochemical devices. Evaluate embodiments.

(Example 1)
FIG. 4 illustrates a cross-sectional view of a fully assembled substitute embodiment for the electrochemical device assembly of Example 1 with a water vapor barrier in accordance with one or more embodiments. Two 4 cm x 4 cm square sheets of Enviromet HS, 75 μm thick aluminized PLA from Celplast, Toronto Ontario, Canada were oriented with the PLA sides facing inward to form an enclosure 400 for the electrochemical device; Stack them together. Seal three of the four edges of the sheet together to create an enclosure pouch 400 with one side open using an MSK-130 heat sealing device with a soft die set to 170 °C for 3 seconds. to produce an enclosure pouch 400 having an inner PLA layer 410 and an outer aluminum layer 412. A water-soaked filter paper 402 and a PLA-D enclosure pouch 404 with sealed edges similar to the embodiment described for Comparative Example 1 are then placed inside the PLA-Al pouch 400 and prepared using MSK-130. , the remaining edge 414 was sealed. The mass of pouch 400 over time was measured to determine water loss.

(Example 2)
FIG. 5 illustrates a cross-sectional view of an embodiment of a fully assembled substitute for the electrochemical device assembly of Example 2 with a water vapor barrier in accordance with one or more embodiments. Enviromet, eight 4 cm x 4 cm square sheets of 75 μm thick aluminized PLA, oriented with the PLA sides facing inward to form a four layer enclosure pouch or water vapor barrier 500 for the electrochemical device. , stacked together. Enclosure pouch 500 with one side open was sealed by sealing three of the four edges of each sheet together using an MSK-130 heat sealing machine with a soft die set to 170°C for 3 seconds. was generated. In this embodiment, the walls of the enclosure pouch 500 include a first layer having a first PLA layer 508 and a first aluminum layer 510, a second layer having a second PLA layer 512 and a second aluminum layer 514. layers, a third layer having a third PLA layer 516 and a third aluminum layer 518, and a fourth layer having a fourth PLA layer 520 and a fourth aluminum layer 522, the Enviromet aluminized PLA 4 laminated sheets are produced. Similar to the embodiment described with respect to Comparative Example 1, a water-soaked filter paper 502 sealed at the edge 506 and a PLA-D enclosure pouch 504 are then placed inside the PLA-Al pouch 500 and the MSK-130 The remaining rim 522 was sealed using a. The mass of enclosure pouch 500 over time was measured to determine moisture loss.

(Example 3)
FIG. 6 illustrates a cross-sectional view of an embodiment of a fully assembled substitute for the electrochemical device assembly of Example 3 with a water vapor barrier in accordance with one or more embodiments. Enviromet, two 4 cm x 4 cm square sheets of 75 μm thick aluminized PLA, oriented with the PLA sides facing inward to form an enclosure pouch 600 with a single water vapor barrier layer for the electrochemical device. , stacked together. An MSK-130 heat sealing machine with a soft die set to 170°C for 3 seconds was used to seal three of the four edges together to produce enclosure pouch 600 with one side open. . In this embodiment, the walls of enclosure pouch 600 consist of a PLA layer 604 and an aluminum layer 606. A 1 cm square patch of Whatman 1825-150 filter paper 602 was placed into a 4 cm x 4 cm enclosure pouch 600. The pouch 600 with the paper patch 602 inside was then weighed and tared. Three drops of DI water were added to the paper 602 of pouch 600, then the last open edge of the pouch was sealed with MSK-130 as before. The mass of the pouch over time was measured to determine water loss.

(Example 4, Example 5, Example 6 and Example 7)
FIG. 7 illustrates a cross-sectional view of an example of an alternative to an electrochemical device assembly having a multilaminate enclosure structure according to the present disclosure. In the multilayer enclosure structure 700, a first side and a second side of the metal barrier layer 702 have a first adhesive bond layer 704 and a second adhesive bond layer 706 disposed on the metal barrier layer 702. Although certain material configurations for multilayer composite structure 700 do not require any adhesive bonding layers, in other embodiments, in instances where the polymer does not adhere to aluminum or other metal surfaces without an adhesive, an adhesive bonding layer may not be required. Note that the presence of layers may also be desirable. In certain examples, the compositions of the adhesive bonding layers 704, 706 are biodegradable, but they are sufficiently thin compared to the metal and polymer layers that these layers may be partially or completely biodegradable. It may also be made of non-biodegradable materials. In such instances, the relative weight percentage of any non-biodegradable material is less than 10% of the total enclosure material weight. In certain examples, the aluminum or metal barrier 702 surface can also have a surface treatment, such as a plasma or corona treatment, that can enhance adhesion to the surface of the one or more metal barrier layers 702. Although it is also anticipated that both the outer first biodegradable polymer layer 708 and the second outer biodegradable polymer layer 710 are constructed of the same material, in certain instances, the first biodegradable The polymer layer 708 and the second biodegradable polymer layer 710 may not be constructed of the same material, and thus the material used for the first biodegradable polymer layer 708 and the second biodegradable polymer layer 710 The material composition of the adhesive bonding layers 704, 706 may differ if needed to optimize adhesion with each polymer type present. The metal layer or metal barrier layer described herein provides the multilayer enclosure structure of the present disclosure with a moisture impermeable or moisture impermeable layer. In certain instances of such multilayer enclosure constructions, the metal layer or metal barrier layer may also prevent the passage of any water, moisture, or solvent through the enclosure.

Example 4: Production of a half-structured multilayer composite using a commercially available three-layer PLA thin film as the adhesive layer. PLA sheets approximately 100 μm thick were obtained by melt extrusion of a blend of commercial extrusion grade PLA obtained from Corbion with a crystallizing agent (Drug D, Luminy D070, available from Corbion). All Foils Inc. A multilayer stack was prepared using a 40 μm thick aluminum foil obtained from , Ohio, USA, a sheet of extruded PLA-D polymer, and a three-layer PLA thin film, Evlon EV-HS1, as the adhesive tie layer between. . The multilayer stack was compressed at 120° C. and 5000 PSI for 20 minutes. The resulting multilayer film can be considered one half of the multilayer structure detailed in FIG. However, since the aluminum layer acts as a water vapor barrier layer, this half structure is sufficient to demonstrate barrier properties in the evaluation of substitutes according to the present disclosure. A complete structure may only be required in certain embodiments to protect the aluminum layer from mechanical damage by adding a polymer scratch-resistant layer. Full structures can be fabricated using the same methods as half structures.

Example 5: Production of a half-structured multilayer composite using a non-biodegradable polyamide-based adhesive as an adhesive layer. A 40 μm thick aluminum foil was coated with a thin layer of polyamide-based adhesive powder (Evonik Vestamelt Hylink) using an electrostatic spray gun and then placed in an oven at 140° C. for 10 minutes. The obtained PLA-D sheet, as detailed in Example 4, was then applied to the adhesive bonding layer side of the aluminum foil and compressed at 120° C. and 5000 PSI for 20 minutes. The adhesive bonding layer has a mass of 2 mg/cm ² while the mass of the half structure is 32.4 mg/cm ² , and the adhesive bonding layer mass is approximately 6% by weight relative to the total mass of the half structure. there were. The mass of the adhesive bonding layer for the complete symmetrical multilaminate structure is thereby calculated to be 4 mg/cm ² out of 54.4 mg/cm ² or 7.4% by weight of the non-biodegradable adhesive bonding layer. Can be done.

Example 6: Production of a multilayer composite half-structure using a thin film of polycaprolactone (PCL) as an adhesive bonding layer. A thin film of PCL adhesive tie layer was obtained by compressing CAPA6500 PCL pellets obtained from Ingevity at 100° C. and 5000 PSI for 20 minutes. A multilayer stack was prepared using 40 μm thick aluminum foil, an extruded sheet of PLA-D as used in Example 4 and according to the present disclosure, and a PCL thin film as adhesive bonding layers. The multilayer stack was compressed at 120° C. and 5000 PSI for 20 minutes.

Example 7: Production of a semi-structured multilayer composite using a thin film of amorphous grade PLA as the adhesive tie layer. A thin film of amorphous PLA layer was produced by compressing the PLA pellet at 200° C. and 5000 PSI for 20 minutes. A multilayer stack was prepared using 40 μm thick aluminum foil, extruded sheets of PLA-D (as in Example 4) and interdigitated amorphous PLA thin films as adhesive bonding layers. The multilayer stack was compressed at 120° C. and 5000 PSI for 20 minutes.

In certain embodiments, the multilayer composites of Examples 6 and 7 are prepared by applying a double layer of adhesive bonding layer and PLA film directly to an aluminum roll, as is commonly practiced in the multilayer packaging manufacturing industry. can be produced in a single step by melt extrusion processing.

To demonstrate the barrier properties of the multilayer composites produced in Examples 4, 5, 6, and 7, sheets of similar dimensions were cut and tested between the interlocking parts of a hand-held heat sealer set at 200°C for 5 seconds. Hermetically sealed pouches of each multilayer laminate (half structure) were prepared by compressing them and thermally sealing their edges. Each pouch contained water-soaked paper tissue. The mass of each pouch was then measured daily as a means to monitor water permeation and subsequent evaporation through the multilayer composite.

FIG. 8 shows a plot of water loss per square centimeter (in milligrams) versus time (in days) for Examples 1-7 in FIGS. 4, 5, 6, and 7 for the comparative example in FIG. The figure shows a comparison with each. For each example, the cumulative water loss per square centimeter (in milligrams) was measured by mass every 24 hours, normalized to surface area, and then plotted. Comparative Example 1, having only the PLA-D substrate as the barrier layer, shows a high cumulative water loss of about 15 mg/cm ² , indicating a total loss of water by day 9. Example 1 with the additional aluminized PLA barrier layer shows significantly reduced cumulative water loss of about 1.34 mg/cm ² by day 9. Example 2 with four combined aluminized PLA barrier layers shows a significant reduction in cumulative water loss of 0.66 mg/cm ² by day 9. Example 3, having only aluminized PLA as a barrier layer, had a moderate cumulative water loss of 2.84 mg/cm ² on day 9 when compared to the total water loss of Comparative Example 1 at a similar time. shows an improved reduction in The multilaminate samples of Examples 4, 5, 6, and 7 showed virtually no or very little water loss by day 9. All results are shown in Tables 1 and 7. It is reported in 2.

Continuity Testing Utilization of biodegradable battery embodiments with barrier layers as described herein may affect the continuity of the battery tab, particularly with respect to the use of heat seals across the tab. presents a problem. This was evaluated by constructing several full size cells similar to Example 2 using aluminized PLA as the outer barrier layer. The use of a low temperature of 135° C. for the MSK sealer further provided a strong seal while preventing unnecessary heat exposure and potential damage to the battery tab. The MSK sealer was set at a low temperature of 135° C. in soft mode for a longer period of 6 seconds. The device was found to be fully functional with no loss of continuity across the tub after heat sealing.

This disclosure has been described with reference to example implementations. Although a limited number of implementations have been shown and described, those skilled in the art will recognize that changes may be made in these implementations without departing from the principles and spirit of the preceding detailed description. ing. It is intended that all such modifications and alterations be considered to be included in this disclosure insofar as they come within the scope of the appended claims or the equivalents thereof.

Claims (20)

anode,
cathode,
An electrochemical device comprising a water vapor barrier including an electrolyte composition and a biodegradable material disposed between an anode and a cathode, the water vapor barrier including the biodegradable material reducing vapor escaping from the electrochemical device. An electrochemical device arranged for The electrochemical device of claim 1, wherein the water vapor barrier further comprises polylactic acid (PLA). The electrochemical device of claim 1, wherein the water vapor barrier further comprises a metallized coating. 4. The electrochemical device of claim 3, wherein the metallized coating comprises aluminum. The electrochemical device of claim 1, wherein the water vapor barrier further comprises multiple layers. 2. The electrochemical device of claim 1, wherein the water vapor barrier further comprises a moisture impermeable layer. 7. The electrochemical device of claim 6, wherein the moisture-impermeable layer comprises a metal. The electrochemical device of claim 7, wherein the metal layer has a thickness of about 1 μm to about 150 μm. 2. The electrochemical device of claim 1, wherein the anode is printed directly onto the water vapor barrier. 2. The electrochemical device of claim 1, wherein the cathode is printed directly onto the water vapor barrier. A water vapor barrier comprising a biodegradable material comprising a polymer and a metal layer coating disposed on the biodegradable material. 12. The water vapor barrier of claim 11, wherein the polymer comprises polylactic acid (PLA). 12. The water vapor barrier of claim 11, wherein the metal layer comprises aluminum. 12. The water vapor barrier of claim 11, further comprising multiple layers. 12. The water vapor barrier of claim 11, wherein the metal layer has a thickness of about 1 μm to about 150 μm. anode,
further comprising a cathode and an electrolyte composition disposed between the anode and the cathode, and a water vapor barrier comprising a biodegradable material encapsulating the anode, cathode, and electrolyte composition;
12. The water vapor barrier of claim 11, wherein the anode, cathode, and electrolyte composition are encapsulated by a water vapor barrier. anode,
cathode,
An electrochemical device comprising an electrolyte composition disposed between an anode and a cathode, and a water vapor barrier comprising a biodegradable material, the device comprising:
a water vapor barrier comprising a biodegradable material is placed to prevent water vapor from escaping the electrochemical device;
the water vapor barrier comprising the biodegradable material further comprising a polylactic acid (PLA) layer and a metal layer;
An electrochemical device, wherein the electrochemical device has a water vapor transmission rate (WVTR) of 1 mg per cm ² or less over 24 hours. 18. The electrochemical device of claim 17, wherein the water vapor barrier further comprises multiple layers. 18. The electrochemical device of claim 17, wherein the metal layer has a thickness of about 0.1 μm to about 10 μm. 18. The electrochemical device of claim 17, wherein the metal layer has a thickness of about 20 μm to about 150 μm.

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