Materials and methods for improving the adhesion of aversive agent coatings to battery cases.

Abstract

To prevent children from eating the electrochemical cell, an electrochemical cell is provided in which at least a portion of the outer surface is coated with an aversive coating. Compositions and methods for improving the adhesion of the aversive coating to the surface of the electrochemical cell are described.

Description

[Technical Field]

[0001] Cross-reference of related applications This application claims priority to U.S. Provisional Application No. 63 / 586,879 filed on 29 September 2023, and to U.S. Non-Provisional Application No. 18 / 593,561 filed on 1 March 2024, which is incorporated herein by reference in its entirety. This application also incorporates, by reference, U.S. Non-Provisional Application No. 18 / 593,391 filed March 1, 2024, claiming priority to U.S. Provisional Application No. 63 / 508,777 filed June 16, 2023; U.S. Non-Provisional Application No. 18 / 593,533 filed March 1, 2024, claiming priority to U.S. Provisional Application No. 63 / 508,745 filed June 16, 2023; and U.S. Non-Provisional Application No. 18 / 593,527 filed March 1, 2024, claiming priority to U.S. Provisional Application No. 63 / 508,764 filed June 16, 2023. field This disclosure generally relates to coin-shaped or button-shaped electrochemical cells. [Background technology]

[0002] background Coin cells or coin cell batteries, such as those described in International Patent Publication PCT / US2013 / 021430, filed January 14, 2013, whose contents are incorporated herein by reference in their entirety, are small, disc-shaped batteries commonly used in a wide range of electronic devices, including hearing aids, cochlear implant processors, calculators, remote controls, and watches. These cells and batteries are often referred to as button cells due to their shape and size. If a child accidentally ingests a coin-shaped battery, it can result in serious injury or even death. This is because, in some cases, the battery's electrolytic reaction, which occurs when it comes into contact with bodily fluids such as tissue fluid, mucus, esophageal mucus, or gastric juice, generates hydroxide (high pH) on the negative electrode side. The formed hydroxide can cause alkaline burns and esophageal perforation. Severe injuries can occur in as little as two hours. To address this issue, many manufacturers implement ingestion prevention features. For example, these features include a bitter coating on the surface of the battery, which deters children from putting the battery in their mouths. However, if a coin-type or button-type cell coated with a bitter agent is swallowed, it will still trigger an electrolytic reaction in the esophagus or stomach, causing serious injury. Therefore, it may be helpful to include a signal to parents or other caregivers that a battery may have been ingested. Such a signal can be achieved by using a coloring agent that stains the mouth, hands, or other areas that have come into contact with bodily fluids such as saliva that have come into contact with a lithium coin-type cell. Some of these coatings may be difficult to adhere to the outer surface of a battery, which can lead to partial or complete wear of the coating during the battery manufacturing process, transportation, or handling, thus reducing the benefits of the coating. Therefore, there is a need for materials and methods to improve the adhesion between coatings containing bittering agents and / or coloring agents and the outer surface of coin-cell or button-cell batteries. [Overview of the project]

[0003] Summary of the Invention Various embodiments provide electrochemical cells in which at least a portion of the outer surface is coated with an aversive coating to prevent children from eating the electrochemical cell. The aversive coating comprises an aversive agent composition and a water-soluble polymer. The aversive agent composition comprises at least one aversive taste agent and may also comprise a colorant. In some embodiments, the aversive taste agent is denatonium benzoate (DNB), capsaicin, allyl isothiocyanate, or piperine. In some embodiments, the aversive taste agent is DNB. The outer surface of the electrochemical cell is prepared for adhesion to the aversive coating by performing a mechanical process on the outer surface of the electrochemical cell or by applying the composition to form a prepared outer surface portion. The composition applied to the outer surface of the cell may be a primer or surface treatment agent to facilitate the adhesion of the aversive coating to the electrochemical cell. In some embodiments, the water-soluble polymer is selected from polyvinyl alcohol (PVA), polyacrylic acid (PAA), polyacrylamide, or polyethylene glycol (PEG). In some embodiments, the water-soluble polymer is PVA. In some embodiments, the PVA has a molecular weight of about 10,000 to about 150,000. In some embodiments, the PVA is hydrolyzed by about 80% to about 95%. In some embodiments, the PVA has a molecular weight of about 75,000 and is hydrolyzed by about 88%.

[0004] In some embodiments, the aversive agent composition further comprises a colorant. In some embodiments, the colorant includes FD&C Blue 1, FD&C Blue 2, FD&C Green 3, FD&C Red 3, FD&C Red 40, FD&C Yellow 5, or FD&C Yellow 6. In some embodiments, the colorant is FD&C Blue 1. In some embodiments, the composition applied to the outer surface of the electrochemical cell is a primer, and the primer comprises a water-soluble polymer. In some embodiments, the composition applied to the outer surface of the electrochemical cell is a surface treatment composition. In some embodiments, the composition applied to the outer surface of the electrochemical cell comprises an adhesion promoter. In some embodiments, the adhesion promoter is Lubrizol 2063, Lubrizol 2062, DowSil Z-6137, DowSil 3-6121, or PP-6. In some embodiments, the composition applied to the outer surface of the electrochemical cell comprises a surfactant. In some embodiments, the surfactant is sodium dodecyl sulfate (SDS).

[0005] In some embodiments, the primer further comprises an aversive taste agent. The primer has a thickness of less than 1 μm. In some embodiments, the primer has a dry mass composition comprising at least 50% by mass of a water-soluble polymer. In some embodiments, the primer comprises PVA or PAA. In some embodiments, the primer further comprises up to 10% by mass of an aversive taste agent such as DNB. In some embodiments, the primer further comprises up to 50% by mass of a surfactant or adhesion promoter. In some embodiments, the electrochemical cell is a coin-type or button-type cell. In some embodiments, more than 50% of the outer surface of the positive and / or negative terminals is coated with an aversive coating. In some embodiments, a portion of the outer surface of the terminals coated with the aversive coating has a shape including one or more of the following: stripes, circles, rings, arcs, ellipses, squares, rectangles, rhombuses, triangles, semicircles, or crescent shapes. In some embodiments, the aversive coating is applied as multiple dots inside an arc shape, ring shape, semicircle shape, or crescent shape. In some embodiments, the aversive coating is applied as multiple dots inside an arc shape, where the arc includes three sub-arcs, and each sub-arc includes multiple dots. In some embodiments, the electrochemical cell is packaged in child-resistant packaging.

[0006] Various embodiments provide a method for producing an electrochemical cell coated with an aversive coating. The method includes the steps of: preparing a primer solution or surface treatment solution; applying the primer solution or surface treatment solution to at least a portion of the outer surface of the electrochemical cell; drying the primer solution or surface treatment solution on the outer surface of the electrochemical cell; preparing a coating solution comprising an aversive agent composition and a water-soluble polymer; applying the coating solution to at least a portion of the outer surface of the electrochemical cell; and drying the coating solution on the outer surface of the electrochemical cell. In some embodiments, the primer solution comprises 0.01% to 0.5% by mass of a water-soluble polymer dissolved in one or more solvents. In some embodiments, the primer solution further comprises 0.001% to 0.5% by mass of an adhesion promoter in one or more solvents. In some embodiments, the primer solution further comprises dissolving 0.001% to 0.5% by mass of a surfactant in one or more solvents. In some embodiments, the primer solution further comprises dissolving 0.001% to 0.02% by mass of an aversive taste agent in one or more solvents.

[0007] The surface treatment solution comprises an adhesion promoter, a surfactant, or an acid dissolved in one or more solvents. In some embodiments, the surface treatment solution contains 0.01% to 5% by mass of an adhesion promoter in one or more solvents. In some embodiments, the surface treatment solution comprises dissolving 0.01% to 0.5% by mass of a surfactant in one or more solvents. In some embodiments, the surface treatment solution is an aqueous solution containing nitric acid, sulfuric acid, hydrochloric acid, or phosphoric acid. In some embodiments, the acid concentration of the surface treatment solution is about 1 N. In some embodiments, the method for preparing an electrochemical cell further includes cleaning the outer surface of the electrochemical cell before applying the coating solution. In some embodiments, the outer surface of the electrochemical cell is prepared for adhesion by performing a mechanical process on the outer surface of the electrochemical cell. In some embodiments, the mechanical process is sandblasting, polishing with sandpaper, tumbling, or milling. Brief Description of the Drawings Reference is now made to the accompanying drawings, which are not necessarily drawn to scale. The accompanying appendices, drawings, figures, images, etc. illustrate various examples, non-limiting aspects of the invention, embodiments, and features (e.g., "for example" or "example") according to the present disclosure.

Brief Description of the Drawings

[0008] [Figure 1] Schematic diagram of a coin-type cell according to one embodiment immersed in a saliva solution. [Figure 2] Perspective view and cross-sectional view of an electrochemical coin-type cell according to one embodiment. [Figure 3] Two-dimensional cross-sectional view of the electrochemical coin-type cell shown in FIG. 2. [Figure 4] Schematic diagram of a process for manufacturing an electrochemical cell coated with an aversion coating. [Figure 5A] Exemplary coating configurations according to various embodiments are shown. [Figure 5B] Exemplary coating configurations according to various embodiments are shown. [Figure 5C] Exemplary coating configurations according to various embodiments are shown. [Figure 5D] Exemplary coating configurations according to various embodiments are shown. [Figure 6A] Results of an adhesion test of the coating on a control cell are shown. [Figure 6B] Results of an adhesion test of the coating applied to a pretreated cell according to a particular embodiment are shown. [Figure 6C] Results of an adhesion test of the coating applied to a pretreated cell according to a particular embodiment are shown. [Figure 7A]Shows the results of an adhesion test of a coating applied to a cell having a primer according to a particular embodiment. [Figure 7B] Shows the results of an adhesion test of a coating applied to a cell having a primer according to a particular embodiment. [Figure 8A] Shows the results of an adhesion test of a coating applied to a cell having a primer, applied by different methodologies, according to a particular embodiment. [Figure 8B] Shows the results of an adhesion test of a coating applied to a cell having a primer, applied by different methodologies, according to a particular embodiment. [Figure 9] Shows an electrochemical cell to which an aversion coating is applied to the negative terminal. [Figure 10] Shows an example of a child-resistant package 600 according to one embodiment.

Mode for Carrying Out the Invention

[0009] Detailed Description Coin-type cell batteries, also known as button-type cells, are small single-cell batteries and are typically used to power low-power devices such as watches, calculators, hearing aids, and small electronic devices. Because these batteries are small and compact, they are easy to use and store and are available in a wide variety of sizes, chemistries, and rated voltages. Coin-type cell batteries were originally developed for use in hearing aids but are now used in a variety of other applications and devices such as watches, calculators, and other small electronic devices. Coin-type cell batteries typically consist of a positive electrode (cathode), a negative electrode (anode), and an electrolyte that allows the flow of ions between the electrodes. The electrodes and electrolyte are typically enclosed in a small circular metal case made of stainless steel or nickel-plated brass.

[0010] The positive electrode is typically made from a metal oxide such as silver oxide or manganese dioxide and coated onto a metal grid or metal foil. The negative electrode is typically made from a metal such as zinc or lithium and is also coated onto a metal grid or metal foil. The electrolyte is typically a liquid or gel and is designed to allow the flow of ions between the electrodes. The electrodes and electrolyte are arranged in a specific configuration within the metal case, depending on the battery's chemical properties and rated voltage. For example, in a manganese dioxide-based battery, the positive electrode is located in the center of the battery, and the negative electrode is located around the outside of the positive electrode. This arrangement allows the battery to deliver a high voltage output while maintaining a small size. The external components include a shell or housing that defines an internal volume for housing the anode and electrodes, which are physically separated by a separator, such as an ion-permeable separator or an electrolyte-permeable separator. The anode and cathode have different active materials, such as zinc and manganese dioxide, respectively. These materials are selected based on their electrochemical properties, which allow for the flow of electrons from one terminal to the other. The electrolyte is a liquid or gel substance that allows for the movement of ions between the anode and cathode. The electrolyte is often a combination of water and a salt, such as potassium hydroxide.

[0011] Coin cell batteries are available in a wide variety of chemical properties, each with its own unique performance characteristics. For example, alkaline coin cell batteries are the most common type of button cell battery and are typically used in low-power devices such as watches, calculators, and small electronic devices. These batteries use an alkaline electrolyte and a zinc-based negative electrode and are available in a wide variety of sizes and rated voltages. Silver oxide coin cell batteries are typically used in high-power devices such as cameras, calculators, and medical devices. These batteries use a silver oxide positive electrode and a zinc-based negative electrode and are designed to achieve high current output and long life. Zinc-air coin cell batteries are typically used in hearing aids and use a zinc-based negative electrode and air as the positive electrode. However, the chemical properties of these batteries often have drawbacks, such as the risk of gas release, explosion risk, fire risk, shortened battery life, uneven discharge, and problems with discharge temperature variation. Lithium is a popular alternative to the chemical properties of other conventional batteries, particularly for use in low-power devices such as watches, calculators, and small electronic devices that use coin cell batteries. These batteries typically use a manganese dioxide-based positive electrode and a lithium-based negative electrode.

[0012] The primary electrochemical reaction that occurs when a coin-type cell is ingested is the electrolysis of water, due to the following factors: (a) the coin-type cell itself supplies a DC voltage, approximately 3V OCV (open-circuit voltage); (b) the ion-conducting medium (saliva) connects the anode (+) terminal and the cathode (-) terminal; and (c) the conduction path of the two terminals and saliva completes the closed circuit of the electrolytic cell. If the voltage supplied to the electrolytic cell is high enough to exceed the thermodynamic voltage range of 1.23V for polarization and electrolysis of water, the electrochemical reaction will occur. In fact, the electrolysis reaction associated with the ingestion of a lithium cell is likely to be more vigorous than the electrolysis reaction associated with the ingestion of an alkaline cell. This is because, in the case of a 3V lithium cell, the driving force (the voltage difference between the cell voltage and the theoretical water electrolysis voltage of 1.23V) is much higher than in the case of a 1.5V alkaline cell (in the case of an alkaline cell, it is 1.5V - 1.23V = 0.27V, whereas in the case of a lithium cell, it is 3.0V - 1.23V = 1.77V). Importantly, the nomenclature for electrolytic cells is the reverse of that used for batteries. Therefore, the terms "anode" and "electrolytic anode" refer to the electrode undergoing oxidation, while the terms "cathode" and "electrolytic cathode" refer to the electrode undergoing reduction. When an electrolytic cell, such as a coin cell, is assembled and the active electrochemical components are sealed within, the negative terminal conducts electrically with the anode or electrolytic anode, and the positive terminal conducts electrically with the cathode or electrolytic cathode. It should also be noted that electrolysis requires the application of voltage, which is in stark contrast to corrosion that typically occurs spontaneously under ambient conditions.

[0013] Figure 1 helps illustrate the electrolytic reaction in question. A simulated Li-MnO2 electrochemical coin-type cell 6 is immersed in a saliva solution 5. The main reaction that would occur if a cell having these same components were accidentally ingested and lodged in the human esophagus is shown, although the cell electrodes are shown as separate components. Specifically, cell 6 operates at a DC voltage of approximately 3V and comprises a coin-type cell cup (e.g., positive electrode container) 12, a coin-type cell can (e.g., negative electrode container) 20, an anode 40, and a cathode 50. The anode 40 and cathode 50 are made of materials specifically selected for their compatibility with the intended electrochemical reaction; for example, xLi + MnO2 → Li-MnO2, in which Mn is reduced as lithium ions enter the crystal lattice. The outer surface of the coin-type cell cup 12 functions as the negative electrode terminal (cathode in an electrolytic cell), and the outer surface of the coin-type cell can 20 functions as the positive electrode terminal (anode in an electrolytic cell). On the coin-type cell cup 12, a hydrogen gas release reaction occurs by receiving electrons from the battery anode 40, which in this case contains lithium. On the coin-type cell can 20 (anode of the electrolytic cell), several reactions occur and compete with each other, including metal dissolution, oxygen gas release, and possibly chloride oxidation. Charge neutrality in the saliva solution 5 is maintained by the movement of anions 8 from the cell cup 12 (negative electrode) to the coin-type cell can 20 (positive electrode), and the movement of cations 7 in the opposite direction. When the metal in the coin-type cell can 20 is oxidized, the metal loses electrons, and these electrons move to the battery cathode 50 (manganese dioxide in this case). Finally, the final product in the coin-type cell can 20 depends on its potential, and the solution pH is a result of the combination of anode and cathode reactions. Furthermore, the solution pH reflects the real-time products generated in the reaction zone between the esophagus and the coin-shaped cell; therefore, the solution pH is local and does not necessarily reflect the pH of the bulk solution (i.e., the residual portion of saliva not adjacent to the reaction zone).

[0014] When a 3V lithium coin cell is immersed in a neutral or alkaline saliva solution, the electrochemical reactions that can occur on the coin cell cup 12 (negative terminal) are shown below. Note that saliva is usually neutral. (1) 2H2O + 2e - → H2↑ + 2OH - E0 = -0.83V (2) O2 + 2H2O + 4e - → 4OH - E0 = -0.4V Typically, the oxygen concentration in saliva is too low due to the limited solubility of oxygen in water, so reaction (1) becomes dominant. In any case, the generation of hydroxyl ions (i.e., OH - ) can increase the pH of saliva and cause alkaline burns in the esophagus. In some cases, saliva can be essentially acidic. The reactions in the coin cell cup 12 in such a situation are shown below: (1a) 2H + + 2e - → H2↑ E0 = -0.0V (2a) O2 + 4H + + 4e - → 2H2O E0 = 1.23V

[0015] In either case, by selecting a material with a high hydrogen gas evolution overvoltage for use as the negative terminal, the dominant reactions change from (1) and (2) to (1a) and (2a). This has the beneficial effect of reducing or eliminating the formation of hydroxyl groups that can cause local alkaline burns in esophageal tissue. When a 3V lithium coin cell is immersed in saliva solution 5 and the coin cell can 20 contains nickel on at least a part of its surface, the electrochemical reactions that can occur on the coin cell can 20 (positive terminal) are shown below. (3) 4OH - - 4e - → O2↑ + 2H2O (4) Ni - 2e - + 2OH - → Ni(OH)2

[0016] Typically, reaction (4) is dominant, and the metallic components within the coin cell can 20 tend to oxidize. In fact, lithium electrochemical coin cell cans are typically nickel-plated, as exemplified by the oxidation of nickel in reaction (4). If the coin cell can 20 is composed of other metals, such as stainless steel, the iron in these alloys is likely to oxidize in a similar reaction. Once the metallic surface of the coin cell can 20 is passivated (i.e., by the formation of a dense oxide film on the exposed metallic surface), the oxygen release reaction (3) is likely to become dominant if the voltage is sufficiently high. Furthermore, as shown in (3a) and (4a) below, dissolution of the metal can 20 is also a possible outcome when an iron-based base metal (usually some type of steel) is exposed, especially to the extent that hydroxides are present (e.g., by the competitive reaction described above) and / or in an acidic environment (e.g., by saliva). (3a)Fe-2e - →Fe 2+ (in acidic medium) (4a)Fe-2e - +2OH - →Fe(OH)2 (in an alkaline medium)

[0017] Any combination of the cathode process in reactions (1) to (2a) and the anode process in reactions (3) to (4a) can be used to complete the electrolytic cell 6 shown in Figure 1. For example, the combination of (1) and (3) results in the following electrolytic reaction (i.e., water splitting) in water: (5)2H2O→H2↑+O2↑ E0=-1.23V Note that the electrolytic reaction (5) has a thermodynamic potential of 1.23V, and the negative sign of ΔE0 indicates that this reaction is not spontaneous. Therefore, a DC power supply of at least 1.23V is required to start and maintain reaction (5), and as shown in Figure 1, the coin cell 6 supplies 3V DC. Furthermore, if the amount of sodium chloride (NaCl) in saliva is relatively high, the following electrolytic reaction may occur instead of reaction (5) (mentioned above): (6)2NaCl+2H2O→Cl2↑+H2↑+2NaOH In reaction (6), one of the products is sodium hydroxide (NaOH), which also increases the pH of the solution and, in some cases, contributes to making the solution alkaline, which can potentially cause burns to human tissue.

[0018] In short, the conventional electrochemical coin cell 6 shown in Figure 1 and the reactions (1) to (6) that occur when it is immersed in saliva 5 demonstrate that hydroxide ions are formed by several repetitions of electrolysis. Therefore, burns and injuries that occur when a coin cell accidentally becomes lodged in the esophagus are likely caused by the high pH of the saliva produced during these reactions, however, the effects of the reactions and the corresponding pH are very localized and may be difficult to detect unless the pH is measured at extremely close range to the components in question. In other words, due to limitations in mass transport in the esophagus, a person with a coin cell lodged in their esophagus may experience different pH values ​​in the tissues interacting with the coin cell can 20 (positive electrode terminal) and the tissues interacting with the coin cell cup 12 (negative electrode terminal), and due to limitations in the diffusion of liquid in the esophagus, the solution with the higher pH is facing the negative electrode terminal (i.e., the coin cell cup 12 in Figure 1). To the extent that certain aspects and underlying concepts of the various embodiments of this disclosure involve saliva and / or saliva-based aqueous solutions, saliva can be represented by the following composition: 0.4g KCl; 0.4g NaCl; 0.906g CaCl2; 0.560g Na3PO4 - Prepare a 1-liter solution by mixing 1 / 2H2O; 2 ml 10% H3PO4; 0.0016 g Na2S; 1 g urea; and the remainder as deionized water. This formulation is intended to approximate human saliva using standardized methods, but slightly modified forms and / or actual human saliva may be used as substitutes, provided that appropriate consideration is given to any deviations from the typical formulation.

[0019] Figures 2 and 3 show one configuration of the electrochemical coin cell 10 well suited to the aspects and embodiments of this disclosure, although the coin cell 10 may be subject to various alternative orientations and arrangements of its components. Furthermore, the specific devices and processes shown in the accompanying drawings and described herein are exemplary embodiments of the inventive concept as defined in the accompanying claims. Accordingly, the exact dimensions and physical properties relating to the embodiments disclosed herein should not be considered limiting unless such dimensions or properties are intrinsic to producing the desired reaction. As shown in Figures 2 and 3, the electrochemical coin cell 10 also includes a cathode terminal 20 (i.e., cell can) which includes a closed end 21, an open end 22 with a terminal edge 23, and a side wall 24 extending between the closed end 21 and the open end 22. The cathode terminal 20 functions as the positive electrode of the coin cell. In addition, the cathode terminal 20 includes a metallic material such as titanium, titanium alloy, titanium nitride, tantalum, niobium, stainless steel, gold, boron-doped diamond, or another electron conductor. The closed end 21 may be provided with a composition including titanium metal, titanium alloy, titanium nitride, tantalum, niobium, stainless steel, gold, boron-doped diamond, or another electron conductor.

[0020] The coin-type cell 10 further includes a gasket 30 that provides a seal between the anode terminal 12 and the cathode terminal 20 (Figures 2 and 3). The gasket 30 is typically made from a non-conductive elastomer material that can provide a compression seal between the anode terminal 12 and the cathode terminal 20. The material used for the gasket 30 should also be selected with reference to its stability in the presence of an electrolyte, its elasticity, and its resistance to cold flow. Suitable materials for the gasket 30 include nylon, polytetrafluoroethylene, fluorinated ethylene propylene, chlorotrifluoroethylene, perfluoroalkoxy polymer, polyvinyl, polyethylene, polypropylene, polystyrene, and polysulfone. The electrochemical coin cell 10 also includes an electrolyte 34. As those skilled in the art will understand, various materials can be used for the electrolyte 34. For example, the electrolyte 34 may consist of a composition in which at least one lithium salt is dissolved in an organic solvent or a blend of organic solvents. Suitable salts for use in lithium coin cells are lithium trifluoromethanesulfonate, lithium trifluoromethanesulfonimide, lithium perchlorate, lithium tetrafluoroborate, lithium hexafluorophosphate, or a combination thereof. Common organic solvents used in lithium coin cells are propylene carbonate and 1,2-dimethoxyethane.

[0021] The electrochemical cell 10 also has an anode 40 electrically connected to an anode terminal 12. As will be understood by those skilled in the art, the anode 40 can be made of various alkali metals and alloys thereof with aluminum or magnesium, as long as their composition is suitable for functioning as an anode in an electrochemical cell. In one embodiment, the anode 40 is mainly made of a lithium material suitable as an anode in an electrochemical cell, which includes a cathode mainly made of manganese dioxide. The electrochemical cell 10 also includes a cathode 50 arranged to be electrically connected to a cathode terminal 20. As will be understood by those skilled in the art, the cathode 50 can be made of a variety of materials suitable for use as a cathode in a lithium-based electrochemical cell. In one embodiment, the cathode 50 is made primarily of manganese dioxide.

[0022] The electrochemical coin cell 10 further includes a separator 38 positioned between the anode 40 and the cathode 50 to provide insulation between them. The separator 38 can be made of any of a variety of polymer materials that provide electrical insulation between the anode terminal 12 and the cathode terminal 20, for example. For example, the separator 38 can be formed from a polypropylene or polyethylene nonwoven film with a thickness of about 20 μm to about 60 μm. As shown in Figures 2 and 3, the electrochemical cell 10 can be configured as a button-shaped or coin-shaped cell having an overall outer diameter 54 and an overall height 58. The overall outer diameter 54 can be between approximately 5 mm and 25 mm, and the overall height 58 can be between approximately 0.5 mm and 10 mm. Button-shaped or coin-shaped cells with these dimensions are generally understood to be most likely to become lodged in the esophagus if accidentally ingested. For example, the electrochemical cell 10 may be manufactured in the CR2016 configuration as defined by the International Electrotechnical Commission (IEC), where the overall outer diameter 54 is approximately 20 mm in diameter and the overall height 58 is approximately 1.6 mm thick.

[0023] Another aspect of the disclosed approach relates to a method for constructing and / or manufacturing a coin-type cell having the features discussed herein. This method includes the steps of providing a lithium-containing negative electrode active material and placing the material in separate halves of a conductive container, and providing a non-aqueous organic liquid electrolyte and then sealing the halves of the conductive container to create a battery. Another aspect of the disclosed approach is the provision and / or manufacture of a battery to avoid injury associated with battery ingestion, and a method for avoiding injury caused by battery ingestion. In these aspects, any of the aforementioned battery designs and structures can be provided. The methods of the present invention essentially involve manufacturing a battery and providing said battery for sale and / or use by consumers. As shown in Figure 5A, without additional preparation, the aversive coating 502 may not adhere properly to the outer surface of the electrochemical cell 501. One approach to address this challenge is to treat the surface of the electrochemical cell with a composition 510 that can fix the cell surface 501 to the polymer in the aversive coating 502, as shown in Figure 5B. Another approach, shown in Figure 5C, involves depositing a thin layer of primer 520 on the cell surface 501 before applying the aversive coating 502. In other embodiments, as shown in Figure 5D, this includes adding a composition such as an adhesion promoter and / or surfactant to the aversive coating 530 to promote adhesion to the cell surface 501.

[0024] Aversion coating Aspects of this disclosure relate to aversive coatings for electrochemical cells. The aversive coatings are formed by applying a solution containing an aversive agent composition and a binder such as a water-soluble polymer to a surface (e.g., the surface of a battery) and allowing the solution to dry. The aversive composition comprises at least one aversive agent, which may be an aversive taste agent such as a bittering agent, an aversive odorant, or a salivary secretion stimulant. "Aversive taste agent" refers to a substance that is bitter, sour, spicy, peppery, or otherwise has an undesirable flavor, intended to deter children from eating batteries. "Aversive odorant" refers to an odorant having an undesirable smell, such as ammonia or sulfur. "Salivary secretion stimulant" refers to a substance that induces saliva secretion when it comes into contact with the mouth. The aversive agent composition may also contain a colorant to warn a parent or guardian that a child has attempted to eat a battery. In some embodiments, the aversive coating has a dry mass composition comprising 0.5% to 65% by mass of an aversive agent composition and 5% to 98.5% by mass of a water-soluble polymer. In some embodiments, the aversive coating includes one or more additives to balance the dry mass composition.

[0025] The aversive agent composition comprises at least one aversive taste agent. In some embodiments, the aversive taste agent is selected from denatonium benzoate (DNB), capsaicin, allyl isothiocyanate, or piperine. In some embodiments, the aversive taste agent is DNB. In some embodiments, the aversive coating has a dry mass composition containing 0.5% to 8.0% by mass of the aversive taste agent (e.g., DNB). In some embodiments, the aversive coating has a dry mass composition containing about 5.0% to about 7.0% by mass of DNB. In some embodiments, the aversive coating has a dry mass composition containing about 6.0% by mass of DNB. The water-soluble polymer contained in the aversive coating acts as a binder for adhering the aversive agent composition to the electrochemical cell. In some embodiments, the dry mass composition of the aversive coating includes 10% to 98.5% by mass, 15% to 95% by mass, 20% to 90% by mass, 30% to 80% by mass, 35% to 70% by mass, 35% to 60% by mass, 35% to 50% by mass, or 35% to about 45% by mass of the water-soluble polymer. In some embodiments, the dry mass composition of the aversive coating includes about 41% by mass of the water-soluble polymer.

[0026] In some embodiments, the water-soluble polymer is selected from polyvinyl alcohol (PVA), polyacrylic acid (PAA), polyacrylamide, or polyethylene glycol (PEG). In some embodiments, the water-soluble polymer is PVA. In some embodiments, the water-soluble polymer has a molecular weight of about 10,000 to about 150,000, about 10,000 to about 100,000, about 50,000 to about 100,000, about 60,000 to about 90,000, about 70,000 to about 80,000, or about 75,000. In some embodiments, PVA has a molecular weight of approximately 10,000 to 150,000, 10,000 to 100,000, 50,000 to 100,000, 60,000 to 100,000, 60,000 to 90,000, 70,000 to 100,000, 70,000 to 90,000, or 70,000 to 80,000. In some embodiments, PVA has a molecular weight of approximately 75,000. All molecular weights are given as average mass in grams per mole. Polyvinyl alcohol is prepared by hydrolyzing polyvinyl acetate from ester functional groups to hydroxyl functional groups. Polyvinyl alcohol can be hydrolyzed to varying degrees. In the case of 80% hydrolyzed PVA, about 80% of the monomer units contain hydroxyl groups and about 20% of the monomer units contain acetate. In some embodiments, PVA is hydrolyzed to about 70% to 100%, about 70% to about 99%, about 80% to about 99%, about 85% to about 95%, about 80% to about 90%, or about 85% to about 90%. In some embodiments, PVA is hydrolyzed to about 80% to about 95%. In some embodiments, PVA is hydrolyzed to about 88%. In some embodiments, PVA has a molecular weight of about 75,000 and is hydrolyzed to about 88%.

[0027] In some embodiments, one or more additives in the aversive coating include an adhesion promoter. In some embodiments, the dry mass composition of the aversive coating includes 0.1% to about 5.0% by mass of the adhesion promoter. In some embodiments, the adhesion promoter is Lubrizol 2063, Lubrizol 2062, DowSil Z-6137, DowSil 3-6121, or PP-6 (PP water manufactured by Marabin Environmental Conservation Printing Ink Co. Ltd.), BYK-4509, or BYK-4510. In some embodiments, the adhesion promoter is Lubrizol 2063, which is a hydroxy and carboxy functionalized phosphate ester. In some embodiments, the dry mass composition of the aversive coating includes 2.0% to 5.0% by mass of Lubrizol 2063. In some embodiments, the dry mass composition of the aversive coating includes about 4.1% by mass of Lubrizol 2063.

[0028] In some embodiments, one or more additives in the aversive coating include a surfactant. In some embodiments, the dry mass composition of the aversive coating includes 0.01% to about 0.5% by mass of surfactant. In some embodiments, the surfactant is an alkyl sulfate, alkyl ether sulfate, alkylbenzene sulfonate, polyoxyethylene ether, phosphate ester, or carboxylate. In some embodiments, the surfactant is sodium dodecyl sulfate (SDS), sodium lauryl ether sulfate (SLES), sodium stearate, Triton X-100, polysorbate 20 (Tween® 20), or sodium dioctyl sulfosuccinate (DOSS). In some embodiments, the surfactant is sodium dodecyl sulfate (SDS). In some embodiments, the dry mass composition of the aversive coating includes about 0.4% by mass of SDS.

[0029] In some embodiments, one or more additives (zone or more additives) of the aversive coating include a viscosity modifier to assist in the dispensing of the solution containing the aversive coating. In some embodiments, the dry mass composition of the aversive coating includes 0.01% to about 2.0% by mass of the viscosity modifier. In some embodiments, the viscosity modifier is a carbomer, i.e., a high molecular weight synthetic polymer of acrylic acid and allyl sucrose or allyl pentaerythritol, such as Carbopol® (e.g., Aqua SF-1, Aqua SF-3, Aqua CC, Silk100, SC-800, 980 polymer, Ultrez10, Ultrez21) or Pemulen® (e.g., TR-1, TR-2, EZ-4U). In some embodiments, the viscosity modifier is polyethylene glycol (PEG), which can have various molecular weights such as PEG-400. In some embodiments, the viscosity modifier is a natural polysaccharide such as xanthan gum, guar gum, or cellulose gum. In some embodiments, the viscosity modifier is a cellulose derivative such as carboxymethylcellulose (CMC) or hydroxyethylcellulose (HEC). Examples of viscosity modifiers include, but are not limited to, Viscolam®, Esaflor®, Ammonyx®, Ninol®, and Amphosol® thickeners. In some embodiments, the viscosity modifier is carboxymethylcellulose (CMC).

[0030] In some embodiments, the aversive agent composition further comprises a colorant. In some embodiments, the dry mass composition of the aversive coating comprises 0.5% to 60% by mass of the colorant. In some embodiments, the dry mass composition of the aversive coating comprises 5% to 55% by mass, 10% to 55% by mass, 20% to 55% by mass, 30% to 55% by mass, 40% to 55% by mass, or 45% to 55% by mass of the colorant. In some embodiments, the colorant comprises FD&C Blue 1 (Brilliant Blue FCF), FD&C Blue 2 (Indigotine), FD&C Green 3 (Fast Green FCF), FD&C Red 3 (Erythrosine), FD&C Red 40 (Allura Red AC), FD&C Yellow 5 (Tartrazine), or FD&C Yellow 6 (Sunset Yellow). The colorants may also include natural organic dyes such as Veg Blue WS180 or Veg Bright Yellow CWD25, available from FoodRGB, Inc. In some embodiments, the dry mass composition of the aversive coating contains about 45% to about 55% by mass of FD&C Blue 1. In some embodiments, the dry mass composition of the aversive coating contains about 50% by mass of FD&C Blue 1.

[0031] In one embodiment, the aversive coating has a dry mass composition comprising about 5.0% to about 7.0% by mass of DNB, about 35% to about 45% by mass of PVA, and about 45% to about 55% by mass of FD&C Blue No. 1. In one embodiment, the aversive coating has a dry mass composition comprising about 5.0% to about 7.0% by mass of DNB, about 35% to about 45% by mass of PVA, 45% to about 55% by mass of FD&C Blue No. 1, and about 2.0% to about 5.0% by mass of Lubrizol 2063. In one embodiment, the aversive coating has a dry mass composition comprising about 5.0% to about 7.0% by mass of DNB, about 35% to about 45% by mass of PVA, 45% to about 55% by mass of FD&C Blue No. 1, and about 0.4% by mass of SDS. In one embodiment, the aversive coating has a dry mass composition comprising about 5.0% to about 7.0% by mass of DNB, about 45% to about 55% by mass of PVA, about 45% to about 55% by mass of FD&C Blue No. 1, about 2.0% to about 5.0% by mass of Lubrizol 2063, and about 0.4% by mass of SDS. In one embodiment, the aversive coating has a dry mass composition comprising about 5.0% to about 6.0% by mass of DNB, about 40% to about 50% by mass of PVA, about 40% to about 50% by mass of FD&C Blue No. 1, and about 1% to about 2% by mass of CMC.

[0032] In one embodiment, the aversive coating has a dry mass composition comprising about 1.0% to about 6.0% by mass of capsaicin, about 40% to about 50% by mass of PVA, and 40% to about 50% by mass of FD&C Blue No. 1. In one embodiment, the aversive coating has a dry mass composition comprising about 5.0% to about 6.0% by mass of DNB, about 40% to about 50% by mass of PVA, about 40% to about 50% by mass of FD&C Blue No. 1, and about 1.0% to about 5.0% by mass of DowSilZ-6137. In one embodiment, the aversive coating has a dry mass composition comprising about 13% to about 20% by mass of DNB and about 75% to about 87% by mass of PVA. In one embodiment, the aversive coating has a dry mass composition comprising about 13% to about 20% by mass of DNB, about 75% to about 87% by mass of PVA and about 2.0% to about 3.0% by mass of Lubrizol 2063. In one embodiment, the aversive coating has a dry mass composition comprising about 13% to about 20% by mass of DNB, about 75% to about 87% by mass of PVA and about 0.1% to about 0.5% by mass of SDS. In one embodiment, the aversive coating has a dry mass composition comprising about 2.0% to about 6.0% by mass of DNB, about 70% to about 80% by mass of polyacrylic acid (PAA), and about 5% to about 28% by mass of FD&C Blue No. 1. In another embodiment, the aversive coating has a dry mass composition comprising about 2.0% to about 6.0% by mass of DNB, about 70% to about 80% by mass of polyacrylic acid (PAA), about 5% to about 28% by mass of FD&C Blue No. 1, and about 1% to about 2% by mass of CMC.

[0033] Electrochemical cell Aspects of this disclosure relate to an electrochemical cell at least partially coated with one or more aversive coatings described herein. The electrochemical cell comprises: a positive terminal defining a first portion of the outer surface of the electrochemical cell; a negative terminal electrically insulated from the positive terminal and defining a second portion of the outer surface of the electrochemical cell; an anode located inside the electrochemical cell and electrically connected to the negative terminal; and a cathode located inside the electrochemical cell, the cathode electrically isolated from the anode and electrically connected to the positive terminal. At least a portion of the outer surface of the electrochemical cell is prepared for adhesion to the aversive coating by applying a composition to the outer surface of the electrochemical cell to form a prepared outer surface portion. The prepared outer surface portion is coated with the aversive coatings provided herein. In some embodiments, the electrochemical cell is a button cell or a coin cell. In some embodiments, the electrochemical cell is a lithium coin cell. Lithium coin cells include, but are not limited to, CR1025, CR1216, CR1616, CR1620, CR1632, CR2016, CR2025, CR2032, CR2430, and CR2450 batteries. Coin cell batteries generally have diameters of 10 mm, 12.5 mm, 16 mm, 20 mm, and 24 mm, and terminal areas of approximately 79 mm² each. 2 , 123mm 2 , 201mm 2 , 314mm 2 , and 452mm 2 That is the case.

[0034] In some embodiments, the electrochemical cell is prepared for adhesion by applying a primer to the electrochemical cell before applying the aversive coating. The primer comprises a water-soluble polymer, which may be the same as or different from the water-soluble polymer used in the aversive coating. For example, the aversive coating may contain PVA, while the primer contains PAA. Furthermore, the molecular weight and degree of hydrolysis may differ between the aversive coating and the primer. For example, the aversive coating may contain approximately 88% hydrolyzed PVA with a molecular weight of approximately 75,000, while the primer contains approximately 80% hydrolyzed PVA with a molecular weight of approximately 50,000. By using different polymers for the primer and coating, beneficial effects can be obtained in which the coating is bonded to the outer surface of the cell while maintaining a thin overall thickness of the primer and coating. For example, a low molecular weight polymer may be used in the primer, which may facilitate the application of a thin-thickness primer, while a high molecular weight polymer may be used in the coating, which may facilitate the adhesion of the aversive agent composition to the primer (and the surface of the cell). The primer has a dry mass composition comprising at least 50% by mass of a water-soluble polymer such as PVA or PAA. The primer is applied as a thin coating less than 1 μm thick so as not to impair the performance of the battery. It may be preferable for the primer to be less than 0.8 μm or less than 0.6 μm thick. The total dry mass of the primer applied to each electrochemical cell may be about 0.1 mg to about 0.5 mg, preferably about 0.1 mg to about 0.2 mg.

[0035] The primer may further contain one or more additives, such as adhesion promoters and / or surfactants, to help the primer adhere to the surface of the electrochemical cell. The dry mass of the primer may contain up to 50% by mass of adhesion promoters and / or surfactants. In some embodiments, the primer contains Lubrizol 2063, Lubrizol 2062, DowSil Z-6137, DowSil 3-6121, or PP-6. In some embodiments, the primer contains SDS. In some embodiments, the primer further contains up to 10% by mass of an aversive taste agent, such as DNB. Additives in the primer, such as adhesion promoters that bond to the metal surface of the battery case, improve the adhesion of the primer to the electrochemical cell surface. The application of the primer prepares the outer surface portion of the electrochemical cell for adhesion to the aversive coating, because the water-soluble polymers in the aversive coating can form a strong interaction with the water-soluble polymers in the primer. Therefore, the application of the primer can improve the adhesion of the aversive coating to the electrochemical cell.

[0036] In some embodiments, the electrochemical cell is prepared for adhesion by applying a surface treatment composition to the electrochemical cell before applying the aversive coating. The application of the surface treatment composition can prepare the outer surface of the electrochemical cell for adhesion to the aversive coating by cleaning, etching, or activating the surface of the battery case, or by bonding with water-soluble polymers in the battery case and the aversive coating. The surface treatment composition may contain adhesion promoters and / or surfactants or acids to prepare the surface of the electrochemical cell for better adhesion to the aversive coating. In some embodiments, the surface treatment composition includes Lubrizol 2063, Lubrizol 2062, DowSil Z-6137, DowSil 3-6121, or PP-6. In some embodiments, the surface treatment agent includes SDS. In some embodiments, the surface treatment composition includes an acidic aqueous solution such as nitric acid, sulfuric acid, hydrochloric acid, or phosphoric acid. The acid solution may have a concentration of approximately 1N.

[0037] In some embodiments, more than 2, 3, 4, 5, 10, 20, 30, 40, 50, 60, 70, 80, or 90 area percent of the positive and / or negative terminals are prepared for adhesion. All or part of the prepared outer surface portion may be coated with an aversive coating. In one example, the entire outer surface of the electrochemical cell is coated with a thin layer of primer, followed by a thin layer of the aversive coating. In another example, the entire surface of the negative or positive terminal is coated with a thin layer of primer, and the aversive coating is applied to the primer-coated portion of the terminal. In yet another example, the entire outer surface of the electrochemical cell is surface-treated, and the portion of the positive or negative terminal is coated with the aversive coating. Figure 9 shows an example of a coin cell in which an anti-hatred coating is applied to the outer surface portion of the negative electrode terminal. In the illustrated example, the anti-hatred coating is applied as a series of dots 70 that collectively cover a portion of the negative electrode terminal. This series of dots is arranged to form an arc on the surface of the battery. However, it should be understood that other patterns such as stripes, rings, ellipses, squares, rectangles, and rhombuses may also be used. To prevent or reduce interference with the battery's performance, the anti-hatred coating may be located approximately 14.0 mm in diameter inward from the center of the terminals of the coin cell and approximately 8.2 mm in diameter outward. In some embodiments, the anti-hatred coating is not located on the sidewalls 24 of the gasket 30.

[0038] In some embodiments, more than 50% of the outer surface of the positive terminal is coated with an anti-averse coating. The outer surface 25 of the positive terminal 20 is shown in Figures 2 and 3. In some embodiments, more than 50% of the outer surface of the negative electrode terminal is coated with an anti-averse coating. The outer surface 17 of the negative electrode terminal 12 is shown in Figures 2 and 3. In some embodiments, the sidewalls of the gasket are not coated with the anti-corrosive coating. The sidewalls 24 of the gasket 30 are shown in Figures 2 and 3. In some embodiments, the total dry mass of the aversive coating applied to the electrochemical cell is about 0.1 mg to about 1.2 mg. In some embodiments, the total dry mass of the aversive coating applied to the electrochemical cell is about 0.2 mg to about 0.5 mg. In some embodiments, the total dry mass of the aversive coating applied to the electrochemical cell is about 0.4 mg. In some embodiments, the total amount of aversive tastochemical applied to the electrochemical cell is between 1 μg and 120 μg, between 5 μg and 100 μg, between 5 μg and 50 μg, between 10 μg and 50 μg, between 10 μg and 40 μg, between 10 μg and 30 μg, between 10 μg and 25 μg, between 20 μg and 40 μg, or between 20 μg and 30 μg. In some embodiments, the total amount of aversive tastochemical applied to the electrochemical cell is approximately 25 μg. In some embodiments, the aversive tastochemical is applied to both the primer and the aversive coating.

[0039] In some embodiments, electrochemical cells are packaged for sale in child-resistant packaging. While the embodiment in Figure 10 shows two batteries 610 arranged within a child-resistant package 600, it should be understood that in other embodiments, one or more batteries may be packaged within a single child-resistant package. As shown, the child-resistant packaging can be implemented as a blister pack having a flat cardboard backing 601 and overlapping thermoformed plastic layers 602 bonded to the surface of the flat cardboard backing 601. In the illustrated embodiment, the thermoformed plastic layers 602 include a battery holder 603 shaped to hold one or more batteries enclosed within the packaging. The battery holder 603 has an open end and defines a recess sized to accommodate one or more batteries completely within the battery holder 603, so that the flat cardboard backing 601 can be secured across the open end of the recess. Furthermore, the plastic layers 602 further include reinforcing ridges surrounding the battery holder 603. The reinforcing ridge 604 is hollow and extends in the same direction as the battery holder 603. The reinforcing ridge 604 provides additional rigidity to the child-resistant packaging 600, preventing children from bending the child-resistant packaging 600 and removing the batteries stored inside.

[0040] The plastic layer 602 may be composed of any of the various thermoplastics. For example, the plastic layer may be polyvinyl chloride (PVC), but other plastic materials may be used. The plastic layer may be thick enough to prevent children from tearing it. For example, the plastic layer may be thicker than 3 mil (about 0.75 mm) (e.g., between 3 and 7 mil). As described above, the plastic layer 602 may be bonded to the flat cardboard backing 601 using an adhesive. For example, the adhesive may be a polyurethane-based adhesive, but other adhesives may be used. More than 50% of the area of ​​the flat cardboard backing 601 may be bonded to the flat portion of the plastic layer 602. The higher the percentage of the flat cardboard backing 601 bonded to the plastic layer 602, the more difficult it will be for a child to peel the flat cardboard backing 601 from the plastic layer 602 and remove the battery from there. Therefore, in certain embodiments, more than 60%, more than 70%, more than 80%, or more than 90% of the area of ​​the flat cardboard backing 601 may be bonded to the plastic material 602. Furthermore, as shown in Figure 10, the plastic layer 602 may be sized to cover the entire flat cardboard backing 601. In this way, a child cannot bend the flat cardboard backing 601 to peel the plastic layer 602 from the surface of the flat cardboard backing 601 or otherwise remove it.

[0041] Method for preparing an electrochemical cell containing an aversive coating. A method for preparing an electrochemical cell coated with an aversive coating is described herein. The electrochemical cell disclosed herein can be prepared according to any method known in the art. The method includes preparing at least a portion of the outer surface of the electrochemical cell for adhesion to the aversive coating by applying a primer or surface treatment agent. A primer solution or surface treatment solution is prepared, applied to the electrochemical cell, dried, and then a coating solution is applied to form the aversive coating. As shown in Figure 4, a method for manufacturing coated electrochemical cells on an assembly line may include the steps of: loading trays of electrochemical cells after manufacturing; performing a pretreatment process; applying a coating solution; drying the coating on the electrochemical cells; and unloading the trays for packaging.

[0042] The outer surface of the electrochemical cell can be cleaned after the manufacture of the electrochemical cell, and this cleaning may be performed as part of a pretreatment process 200, prior to step 300 in which the coating solution is applied. In certain embodiments, the pretreatment process 200 includes applying a primer solution or surface treatment solution to the electrochemical cell and drying the primer or surface treatment solution before applying the coating solution to form an aversive coating. The surface of the electrochemical cell may be cleaned to remove grease or residue from the manufacturing process, which may facilitate the adhesion of the coating solution to the electrochemical cell. In some embodiments, the electrochemical cell is sprayed with deionized water for a certain period of time (e.g., 5-10 seconds) before applying the coating solution. In some embodiments, the electrochemical cell is rinsed at a temperature higher than room temperature (e.g., 27°C-35°C). The electrochemical cell may be dried before applying the coating solution. In some embodiments, the electrochemical cell is rinsed for a certain period of time (e.g., 1-5 seconds) and then dried with hot air. In some embodiments, the electrochemical cell is dried with air at a temperature of about 25°C.

[0043] In embodiments utilizing a primer solution, the primer solution is prepared by dissolving 0.1% to 0.5% by mass of a water-soluble polymer such as PVA or PAA in a solvent. In some embodiments, the primer solution further comprises 0.001% to 0.5% by mass of an adhesion promoter. In some embodiments, the adhesion promoter is Lubrizol 2063, Lubrizol 2062, DowSil Z-6137, DowSil 3-6121, or PP-6. In some embodiments, the primer solution contains about 0.1% by mass of Lubrizol 2063. In some embodiments, the primer solution further comprises 0.001% to 0.5% by mass of a surfactant such as SDS. In some embodiments, the primer solution contains about 0.1% by mass of SDS. In some embodiments, the primer solution further comprises 0.01% to 2.0% by mass of a viscosity modifier such as CMC. In some embodiments, the primer solution further comprises 0.001% to 0.02% by mass of an aversive taste agent such as DNB. As discussed herein, the primer solution may be applied directly to the surface of the electrochemical cell (e.g., the entire surface of the electrochemical cell or a portion of the surface of the electrochemical cell). In other embodiments, the primer solution may be mixed with the coating solution before applying it to at least a portion of the electrochemical cell.

[0044] In embodiments utilizing a surface treatment solution (with or without the use of a primer solution), the surface treatment solution is prepared by dissolving an adhesion promoter and / or a surfactant, or an acid, in one or more solvents. In some embodiments, the surface treatment solution contains 0.01% to 5% by mass of an adhesion promoter. In some embodiments, the adhesion promoter is Lubrizol 2063, Lubrizol 2062, DowSil Z-6137, DowSil 3-6121, or PP-6. In one embodiment, the surface treatment solution contains about 1.0% by mass of Lubrizol 2063. In some embodiments, the surface treatment solution contains 0.01% to 0.5% by mass of a surfactant, such as SDS. In some embodiments, the surface treatment solution contains about 0.1% by mass of SDS. In some embodiments, the surface treatment solution contains an acidic aqueous solution, such as but not limited to nitric acid, sulfuric acid, hydrochloric acid, or phosphoric acid, at a concentration of about 1 N. Any acidic solution capable of etching the metal case to improve adhesion can be used for surface treatment. Applying a primer and / or surface treatment improves the adhesion of the aversive coating to the outer surface of the battery by strengthening the interaction between the battery case and the aversive coating. For example, applying a surfactant such as SDS to the primer and / or surface treatment helps remove grease or oil, resulting in a metal surface to which the polymer of the aversive coating can adhere better. In some cases, the primer and / or surface treatment may also include an adhesion promoter such as Lubrizol 2063 that bonds to the metal surface of the battery case. In this way, the water-soluble polymer in the aversive coating can bond with the Lubrizol fixed to the surface of the battery case, resulting in an aversive coating that adheres firmly to the battery.

[0045] In some embodiments, the surface treatment for preparing the outer surface of the electrochemical cell for adhesion to an averse coating is a mechanical process for modifying the surface of the metal case. Mechanical or physical surface treatment processes include, but are not limited to, sandblasting, polishing with rough materials such as sandpaper, tumbling, or milling. Other methods for preparing the surface of the electrochemical cell, such as acid-based etching processes or other processes to enhance the potential for adhesion to the cell surface, may be utilized as discussed herein. In some embodiments, the primer and / or surface treatment is applied to an area of ​​the electrochemical cell larger than the area covered by the aversive coating, but overlapping with the area to which the aversive coating is applied. For example, the entire outer surface of the electrochemical cell can be coated with the primer or surface treatment solution, but the aversive coating can be applied only to the negative electrode terminal. In some cases, the entire area of ​​the terminal, such as the negative electrode terminal, is coated with the primer or surface treatment solution, but the aversive coating is applied only to specific parts of the negative electrode terminal, such as the arc-shaped pattern of dots shown in Figure 9, or two rectangular areas spanning the negative electrode terminal. For example, the aversive coating applied to the arc-shaped pattern of dots may cover approximately 11% of the area of ​​the negative electrode terminal of a coin-shaped cell with an outer diameter of 20 mm. The aversive coating applied to two rectangular areas approximately 12.5 mm long and 2 mm wide may cover approximately 16% of the area of ​​the negative electrode terminal of a coin-shaped cell with an outer diameter of 20 mm. In some embodiments, the primer or surface treatment is applied to more than 40%, 50%, 60%, 70%, 80%, or 90% of the total surface area of ​​the outer surface of the electrochemical cell. In some embodiments, the primer or surface treatment is applied to more than 50%, 60%, 70%, 80%, or 90% of the total surface area of ​​the positive or negative terminal of the electrochemical cell. In some embodiments, the aversive coating is applied to 5% to 50% of the surface area of ​​the positive or negative terminal.

[0046] The method includes the steps of: preparing a coating solution by dissolving an aversive agent composition and a water-soluble polymer in one or more solvents; applying the coating solution to a prepared outer surface of an electrochemical cell; and drying the coating solution on the electrochemical cell. The coating solution contains 0.2% to 20% by mass of an aversive agent composition and 0.2% to 14% by mass of a water-soluble polymer dissolved in one or more solvents. The water-soluble polymer and the aversive taste agent are dissolved in a solvent to obtain a coating solution having a final concentration of 0.2% to 14% by mass of the water-soluble polymer and 0.2% to 2% by mass of the aversive taste agent. In some embodiments, the coating solution further contains 0.01% to 3.0% by mass of an adhesion promoter. In some embodiments, the coating solution further contains 0.2% to 18% by mass of a colorant. In some embodiments, the coating solution further contains 0.01% to 0.3% by mass of a surfactant. In some embodiments, the coating solution further contains 0.01% to 2.0% by mass of a viscosity modifier.

[0047] In some embodiments, the coating solution is prepared by dissolving about 12% by mass of PVA, about 1.5% by mass of DNB, and about 12% by mass of FD&C Blue No. 1 in one or more solvents. In some embodiments, the coating solution is prepared by dissolving about 12% by mass of PVA, about 1.5% by mass of DNB, about 12% by mass of FD&C Blue No. 1, and about 1% by mass of Lubrizol 2063 in one or more solvents. In some embodiments, the coating solution is prepared by dissolving about 12% by mass of PVA, about 1.5% by mass of DNB, about 12% by mass of FD&C Blue No. 1, about 1% by mass of Lubrizol 2063, and about 0.1% of SDS in one or more solvents. Water-soluble polymers can be completely dissolved in a coating solution by heating them to a suitable temperature for a set period of time. In some embodiments, the water-soluble polymer is PVA, which is dissolved by heating it to about 95°C for about 60 minutes. In some embodiments, a solution of a dissolved adhesion promoter (e.g., Lubrizol 2063) is added to the coating solution containing the dissolved water-soluble polymer. In some embodiments, the coating solution heated to dissolve the water-soluble polymer is cooled before adding an aversive agent composition which may contain an aversive taste agent and a colorant.

[0048] Primer solutions or surface treatment solutions and aversive coating solutions can be applied to an electrochemical cell using any method known in the art. In some embodiments, the primer solution or surface treatment solution is applied to the electrochemical cell by dipping, brushing, or spraying the primer solution or surface treatment solution. In some embodiments, the coating solution is applied to the electrochemical cell by dipping, spraying, printing, or dispensing the coating solution. In some embodiments, a jet dispenser is used to apply the coating solution (e.g., dots). Alternatively, the coating solution may be applied using methods such as pad printing or screen printing. In embodiments where the aversive coating is applied only to a portion of the positive or negative terminal, a mask can be used to selectively apply the aversive coating to the desired portion of the electrochemical cell. The mask is a solid, non-absorbent material having holes or gaps in a desired pattern, and is placed between the electrochemical cell and a device dispensing the coating solution, allowing the coating solution to be deposited on a specific portion of the electrochemical cell. The mask can be removed after the aversive coating has dried. [Examples]

[0049] Examples As discussed herein, bittering agents, coloring agents, saliva-stimulating agents, and / or other aversive agents may be added to at least a portion of the outer surface of a coin cell battery. Aversive agents may include substances that induce very unpleasant tastes or smells, such as pungent, peppery, sour, bitter, or odiferous. Examples include denatonium benzoate (DNB), capsaicin, allyl isothiocyanate, and piperine. For example, one or more aversive taste agents may be added to a coating that adheres to the outer surface of the battery. In one embodiment, the aversive agent is encapsulated in a PVA network and applied to the battery surface by adding a water-soluble polymer such as polyvinyl alcohol (PVA) to a water-based aversive agent solution. As the water in the aversive agent solution evaporates, the polymer acts as a binder, attaching the aversive agent (and other active substances such as colorants and / or saliva-stimulating agents) to the battery surface. However, the coating maintains solubility in water (or water-like solutions such as saliva), so if a person (e.g., a child) puts the battery in their mouth, the aversive agent is released from the battery surface. The unpleasant taste of the aversive agent may cause a person to spit out the battery rather than swallow it.

[0050] Water-soluble polymers, such as but not limited to PVA and polyacrylic acid (PAA), can be used as binders to the battery surface for aversive agents. The polymers may be low molecular weight polymers (1-10K), medium molecular weight polymers (10-100K), or high molecular weight polymers (>100K). Low molecular weight polymers have high water solubility, short chains resulting in less chain entanglement and high molecular mobility. However, low molecular weight polymers tend to form beads rather than fibers in solution, resulting in weaker materials. High molecular weight polymers have low water solubility but stronger chain entanglement, forming films with high tensile strength. Furthermore, high molecular weight polymers tend to form tougher and more chemically resistant materials. Additionally, the viscosity of the polymer-containing solution increases with increasing molecular weight. Medium molecular weight polymers have moderate water solubility, strength, and viscosity. However, adhesion may be weaker, especially if manufacturing oil used in the formation of battery can components is still present. Various methodologies can be used to improve the adhesion of the polymer to the battery surface.

[0051] The coating can be applied using many different coating methods, such as after preparing the battery surface (e.g., applying a primer to the battery surface, cleaning the battery surface, or pre-treating the battery surface), and then providing small droplets of the material (e.g., via a pipette). Other application methods include dip rinsing of the battery, spraying of the battery, pad printing on the battery, screen printing on the battery, needle dispensing on the battery, and / or similar methods. Any method that uniformly deposits a thin layer and provides at least substantially uniform thickness to the battery surface can be used. In certain embodiments, the coating can be applied directly to the battery surface, and the coating may contain an adhesion promoter. The coating solution itself may have the following composition: solvent (e.g., water, isopropanol, ethanol, mixtures thereof, and / or other organic solvent materials); DNB (or other aversive agents); any additives (e.g., surfactants, adhesion promoters, etc.); any low concentration of polymer binders (e.g., PVA, PAA, polyethylene glycol, polyacrylamide, and / or similar); any viscosity modifiers for better processing (e.g., carboxymethylcellulose (CMC)). In certain embodiments, the coating may further contain adhesion promoters (e.g., DowSil Z-6137, DowSil 3-6121, Lubrizol-2062, Lubrizol 2063H, PP-6, and / or similar). The coating may be applied by spraying.

[0052] The amount of anaerobic agent can be selected to provide an unpleasant taste in the battery. For example, the amount of DNB may be selected to be between 1 and 120 μg (e.g., between 5 and 30 μg) per coin-type cell. The anaerobic agent may include substances that induce a very unpleasant taste or smell, such as pungent, peppery, sour, bitter, or odiferous. Exemplary anaerobic agents include capsaicin, allyl isothiocyanate, and piperine. The coating can be applied using many different coating methods, such as providing small droplets of the material (e.g., via a pipette). Other application methods include dip rinsing of the battery, spraying of the battery, pad printing on the battery, screen printing on the battery, needle dispensing on the battery, and / or similar methods. Any method that uniformly deposits a thin layer can be used. In certain embodiments, additional additives may be provided to further enhance the desired properties of the resulting coating. For example, surfactants can be added to the solution to increase the wettability of the coating. In certain embodiments, the battery surface can also be treated with plasma ultrasound or other means to increase the surface energy and better accept the coating. When coating terminals (e.g., negative terminals), a portion of the terminal (for example, the outermost 1-2 mm to prevent short circuits when wet with a solution) may be masked to prevent the masked area from being coated with the coating material. Then, the coating material may be sprayed onto the terminal, and the mask may be removed after the coating has dried.

[0053] Before coating, the battery may be washed or otherwise prepared to remove any manufacturing oil residue from the battery surface. For example, the battery may be rinsed with deionized water (e.g., periodically treated deionized water with conductivity σ < 10 μS / cm) at 30°C for a total of 8 seconds. Hot air drying may be started 0.5 seconds after rinsing is complete. Hot air drying is performed for approximately 3 seconds at a temperature of 25°C. The coating may be sprayed onto the cleaned battery surface approximately one second after natural drying is complete. The battery may then be dried (for example, by hot air drying) to dry the coating on the cell. If a portion of the cell is masked, the mask may be removed after the coating has dried.

[0054] By spraying a coating material onto specific parts of the cell, the cell's conductivity can be maintained even if the coating thickness hinders electron transfer through it. In other words, if the coating is placed on parts of the cell where conductivity is not critical, the coating does not need to be thin enough to maintain conductivity. If a thick coating layer is applied to some parts of the battery while other uncoated parts of the battery remain uncoated, the total load of aversive agents (e.g., bittering agents) on the battery can be increased. For example, the coating may be applied to the positive and / or negative terminals of the battery. The coating may be applied to a portion of the positive and / or negative terminals, leaving the rest of the terminals exposed.

[0055] conclusion Many modifications and other embodiments of the embodiments described herein will be recalled by those skilled in the art, who have an interest in the teachings shown in the foregoing description and the accompanying drawings. Therefore, it should be understood that this disclosure is not limited to the specific embodiments disclosed, and that modifications and other embodiments are intended to be included within the scope of the appended claims. Furthermore, while the foregoing description and the accompanying drawings illustrate exemplary embodiments in the context of certain exemplary combinations of elements and / or functions, it should be understood that different combinations of elements and / or functions may be provided by alternative embodiments without departing from the scope of the appended claims. In this regard, other combinations of elements and / or functions different from those expressly described above are also conceivable, for example, as may be described in part of the appended claims. Certain terms are used herein, but they are used in a general and descriptive sense only and are not intended to be limiting.

[0056] Unless otherwise specified, all figures used in the specification and claims to represent quantities of components, reaction conditions, etc., should be understood in all cases to be modified by the term “approximately.” Therefore, unless specifically objected, the numerical parameters described herein and in the appended claims are approximations that may vary depending on the desired properties to be obtained by this application. Generally, the term “approximately” as used herein to refer to measurable values ​​such as mass, time, and dosage means that the variation from a given amount is, in one example, ±20%, in another ±10%, in yet another ±5%, in another ±1%, and in yet another ±0.1%, such variation is appropriate for carrying out the disclosed method.

[0057] All examples and / or embodiments described herein are not limiting throughout this disclosure. Furthermore, no inferences should be made regarding embodiments not discussed herein except for purposes of reducing space and repetition, in relation to those embodiments discussed herein. For example, the logical and / or topological structures of any combination of data flow sequences, program components (component collections), other components, and / or the set of functions of the present invention, as described in the drawings and / or throughout this disclosure, are not limited to a fixed operating order and / or arrangement; rather, the disclosed order is illustrative, and all equivalents, regardless of order, are assumed by this disclosure. Furthermore, such functions and steps are not limited to sequential execution, but are also assumed by this disclosure to be able to be executed asynchronously, simultaneously, in parallel, concurrently, synchronously, and / or similarly. Therefore, some of these functions may be mutually contradictory in that they cannot exist simultaneously in a single embodiment. Similarly, some functions may be applicable to certain modified embodiments but not to others. In addition, this disclosure includes other modifications that are disclosed but not expressly described. Therefore, it should be understood that the advantages, embodiments, examples, functions, features, logic, operation, organization, structure, topology, and / or other aspects of this disclosure should not be considered as limitations of the disclosure as defined by the embodiments, examples, or claims, or limitations of the embodiments, examples, and / or equivalents of the claims. It should be understood that various embodiments or parts of various embodiments of the coin cell battery described herein can be implemented, offering great flexibility and customization depending on the specific needs and / or characteristics of the electrochemical cell such as the coin cell.

Claims

1. It is an electrochemical cell, A positive electrode terminal defining a first portion of the outer surface of the electrochemical cell, It comprises a negative terminal that is electrically insulated from the positive terminal and defines a second portion of the outer surface of the electrochemical cell, Here, at least a portion of the outer surface of the electrochemical cell is prepared for adhesion to the anti-averse coating by performing a mechanical process on the outer surface of the electrochemical cell or by applying a composition to form a prepared outer surface portion. The electrochemical cell further, An anode, which is placed inside the electrochemical cell and electrically connected to the negative electrode terminal, A cathode disposed inside the electrochemical cell, electrically isolated from the anode and electrically connected to the positive terminal, an aversive coating covering at least a portion of the prepared outer surface, aversive agent composition, and Water-soluble polymers averse coatings and An electrochemical cell equipped with the following features.

2. The electrochemical cell according to claim 1, wherein the aversive agent composition comprises at least one aversive taste agent selected from denatonium benzoate (DNB), capsaicin, allyl isothiocyanate, or piperine.

3. The electrochemical cell according to claim 1, wherein the water-soluble polymer is selected from the group consisting of polyvinyl alcohol (PVA), polyacrylic acid (PAA), polyacrylamide, and polyethylene glycol (PEG).

4. The electrochemical cell according to claim 1, wherein the water-soluble polymer is PVA, and the PVA has a molecular weight of about 75,000 and is hydrolyzed by about 88%.

5. The electrochemical cell according to claim 1, wherein the aversive agent composition further comprises a coloring agent.

6. The electrochemical cell according to claim 5, wherein the coloring agent comprises FD&C Blue No. 1, FD&C Blue No. 2, FD&C Green No. 3, FD&C Red No. 3, FD&C Red No. 40, FD&C Yellow No. 5, or FD&C Yellow No.

6.

7. The electrochemical cell according to claim 6, wherein the coloring agent is FD&C Blue No.

1.

8. The electrochemical cell according to claim 1, wherein the composition applied to the outer surface of the electrochemical cell is a primer, and the primer has a dry mass composition comprising at least 50% by mass of a water-soluble polymer.

9. The electrochemical cell according to claim 8, wherein the water-soluble polymer of the primer is PVA or PAA.

10. The electrochemical cell according to claim 1, wherein the composition applied to the outer surface of the electrochemical cell is a surface treatment composition.

11. The electrochemical cell according to claim 10, wherein the surface treatment composition contains an acid.

12. The electrochemical cell according to claim 1, wherein the composition applied to the outer surface of the electrochemical cell comprises an adhesion promoter.

13. The electrochemical cell according to claim 12, wherein the adhesion promoter is Lubrizol 2063, Lubrizol 2062, DowSil Z-6137, DowSil 3-6121, or PP-6.

14. The electrochemical cell according to claim 13, wherein the adhesion promoter is Lubrizol 2063.

15. The electrochemical cell according to claim 1, wherein the composition applied to the outer surface of the electrochemical cell comprises a surfactant.

16. The electrochemical cell according to claim 15, wherein the surfactant is sodium dodecyl sulfate (SDS).

17. The electrochemical cell according to claim 8, wherein the primer further comprises up to 10% by mass of the aversive taste agent.

18. The electrochemical cell according to claim 8, wherein the primer has a thickness of less than 1 μm.

19. The electrochemical cell according to claim 1, wherein the outer surface of the electrochemical cell is prepared for adhesion by sandblasting, sanding, tumbling, or milling.

20. The electrochemical cell according to claim 1, which is a button-shaped cell or a coin-shaped cell.

21. The electrochemical cell according to claim 20, wherein a portion of the outer surface of the electrochemical cell prepared for adhesion with the aversive coating includes at least one of the positive electrode terminal or the negative electrode terminal.

22. The electrochemical cell according to claim 21, wherein the aversive coating covers more than 50% of the area of ​​at least one of the positive electrode terminal or the negative electrode terminal.

23. The electrochemical cell according to claim 1, packaged in child-resistant packaging.

24. A method for preparing an electrochemical cell, wherein at least a portion of the outer surface of the electrochemical cell is prepared for adhesion to an aversive coating by applying a primer, the aversive coating comprises an aversive agent composition and a water-soluble polymer, and the method is A step of preparing a primer solution, wherein the primer solution comprises 0.1% to 0.5% by mass of a water-soluble polymer dissolved in one or more solvents, The steps include applying the primer solution to at least a portion of the outer surface of the electrochemical cell, The steps include drying the primer solution on the outer surface of the electrochemical cell to form the prepared outer portion, A step of preparing a coating solution, wherein the coating solution comprises the aversive agent composition and the water-soluble polymer, The steps include applying the coating solution to the prepared outer surface portion of the electrochemical cell, The steps include drying the coating solution on the prepared outer surface portion of the electrochemical cell. Methods that include...

25. The method according to claim 24, wherein the primer solution contains 0.1% to 0.2% by mass of PVA or PAA.

26. The method according to claim 24, wherein the step of preparing the primer solution further comprises dissolving 0.001% to 0.5% by mass of an adhesion promoter in one or more of the solvents.

27. The method according to claim 26, wherein the adhesion promoter is Lubrizol 2063, Lubrizol 2062, DowSil Z-6137, DowSil 3-6121, or PP-6.

28. The method according to claim 24, wherein the step of preparing the primer solution further comprises dissolving 0.001% to 0.5% by mass of a surfactant in one or more of the solvents.

29. The method according to claim 28, wherein the surfactant is sodium dodecyl sulfate (SDS).

30. The method according to claim 24, wherein the step of preparing the primer solution further comprises dissolving 0.001% to 0.02% by mass of an aversive taste agent in one or more of the solvents.

31. The method according to claim 30, wherein the aversive taste agent is denatonium benzoate (DNB), capsaicin, allyl isothiocyanate, or piperine.

32. The method according to claim 24, further comprising the step of cleaning the outer surface of the electrochemical cell before the step of applying the primer solution.

33. A method for preparing an electrochemical cell, wherein at least a portion of the outer surface of the electrochemical cell is prepared for adhesion to an aversive coating by applying a surface treatment composition, the aversive coating comprises an aversive agent composition and a water-soluble polymer, and the method is A step of preparing a surface treatment solution, wherein the surface treatment solution comprises an adhesion promoter, a surfactant, or an acid dissolved in one or more solvents, The steps include applying the surface treatment solution to at least a portion of the outer surface of the electrochemical cell, The steps include drying the surface treatment solution on the outer surface of the electrochemical cell to form the prepared outer surface portion, A step of preparing a coating solution, wherein the coating solution comprises the aversive agent composition and the water-soluble polymer, The steps include applying the coating solution to the prepared outer surface portion of the electrochemical cell, The steps include drying the coating solution on the prepared outer surface portion of the electrochemical cell. Methods that include...

34. The method according to claim 33, wherein the step of preparing the surface treatment solution includes dissolving 0.01% to 5% by mass of an adhesion promoter in one or more solvents.

35. The method according to claim 34, wherein the adhesion promoter is Lubrizol 2063, Lubrizol 2062, DowSil Z-6137, DowSil 3-6121, or PP-6.

36. The method according to claim 33, wherein the step of preparing the surface treatment solution includes dissolving 0.01% to 0.5% by mass of a surfactant in one or more solvents.

37. The method according to claim 36, wherein the surfactant is sodium dodecyl sulfate (SDS).

38. The method according to claim 34, wherein the step of preparing the surface treatment solution includes preparing an aqueous solution containing nitric acid, sulfuric acid, hydrochloric acid, or phosphoric acid.

39. The method according to claim 38, wherein the surface treatment solution has a concentration of about 1 N.

40. The method according to claim 34, further comprising the step of cleaning the outer surface of the electrochemical cell before applying the surface treatment solution.

41. A method for preparing an electrochemical cell, wherein at least a portion of the outer surface of the electrochemical cell is prepared for adhesion to an aversive coating, the aversive coating comprises an aversive agent composition and a water-soluble polymer, and the method is The steps include performing a mechanical process on the outer surface of the electrochemical cell, A step of preparing a coating solution, wherein the coating solution comprises the aversive agent composition and the water-soluble polymer, The steps include applying the coating solution to the prepared outer surface portion of the electrochemical cell, The steps include drying the coating solution on the prepared outer surface portion of the electrochemical cell, Methods that include...

42. The method according to claim 41, wherein the mechanical process performed on the outer surface of the electrochemical cell is sandblasting, sanding, tumbling, or milling.

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