Lithium coin cell batteries in which polymer and aversive agent coatings are located on the outer surface of the cell to avoid affecting conductivity.
Aversive coatings with aversive taste agents and polymers on coin-shaped batteries prevent ingestion and indicate ingestion, addressing the safety risks of electrolytic reactions.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- ENERGIZER BRANDS LLC
- Filing Date
- 2024-06-14
- Publication Date
- 2026-07-24
AI Technical Summary
Coin-shaped batteries, when ingested, can cause severe injuries due to electrolytic reactions with bodily fluids, and existing anti-ingestion features like raised rims and bitter coatings are insufficient to prevent such injuries.
Aversive coatings comprising an aversive taste agent and a water-soluble polymer are applied to the outer surface of the electrochemical cell terminals, covering 2% to 50% of the area, to deter ingestion and provide a visual warning.
The aversive coatings effectively deter children from ingesting the batteries and provide a visible indication of ingestion, reducing the risk of electrolytic reactions and associated injuries.
Smart Images

Figure 2026524837000001_ABST
Abstract
Description
[Technical Field]
[0001] Cross-reference of related applications This application claims priority to 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; 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; and 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; these applications are incorporated herein by reference in their entirety. This application also incorporates, by reference, U.S. Non-Provisional Application No. 18 / 593,561, filed March 1, 2024, which claims priority to U.S. Provisional Application No. 63 / 586,879, filed September 29, 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.
[0003] To address this issue, many manufacturers implement anti-ingestion features. For example, one anti-ingestion feature is a raised rim around the battery. The raised rim makes it difficult for a child to swallow the battery. Other anti-ingestion 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 that is coated with a bitter agent or has a raised rim is swallowed, it will still cause an electrolytic reaction in the esophagus or stomach, leading to 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. [Overview of the Initiative]
[0004] Brief overview Various embodiments provide electrochemical cells coated with an aversive coating comprising an aversive taste agent and a water-soluble polymer as a binder, to prevent children from eating the electrochemical cells. The aversive coating covers 2% to 50% of the outer surface area of at least one terminal of the electrochemical cell. The aversive coating has a dry mass composition comprising 0.5% to 65% by mass of the aversive agent composition and 5% to 98.5% by mass of the water-soluble polymer. The aversive agent composition comprises at least one aversive taste agent and may also contain a coloring agent. In some embodiments, the aversive taste agent is denatonium benzoate (DNB), capsaicin, allyl isothiocyanate, or piperine. 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%.
[0005] In some embodiments, the aversive coating further comprises 0.1% to 5.0% 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 aversive coating contains 2.0% to 5.0% by mass of Lubrizol 2063. In some embodiments, the aversive coating further comprises 0.01% to 1.0% by mass of a surfactant. In some embodiments, the surfactant is sodium dodecyl sulfate (SDS). In some embodiments, the aversive coating further comprises 0.01% to 2.0% by mass of a viscosity modifier. In some embodiments, the viscosity modifier is carboxymethylcellulose (CMC).
[0006] In some embodiments, the aversive agent composition includes a colorant, and the aversive coating includes 0.5% to 60% by mass of the colorant. In some embodiments, the colorant includes 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). In some embodiments, the colorant is FD&C Blue 1.
[0007] In some embodiments, 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 1. In some embodiments, 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, about 45% to about 55% by mass of FD&C Blue 1, and about 2.0% to about 5.0% by mass of Lubrizol 2063. In some embodiments, 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, 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.
[0008] In some embodiments, the electrochemical cell is a coin-shaped cell or a button-shaped cell. In some embodiments, the aversive coating is located on the outer surface of the terminal, approximately 14 mm inward from the center of the terminal. In some embodiments, the aversive coating is located on the outer surface of the terminal, approximately 8.2 mm outward from the center of the terminal. In some embodiments, the area of the outer surface of the terminal coated with the aversive coating has a shape including one or more of the following: stripe, circle, ring, arc, ellipse, square, rectangle, rhombus, triangle, semicircle, or crescent. In some embodiments, the aversive coating is provided on the outer surface of the terminal in an arc or ring shape, with an outer diameter of approximately 14 mm and an inner diameter of approximately 8.2 mm, and the arc is centered relative to the terminal. In some embodiments, the arc has an angular length between approximately 90° and approximately 270°. In some embodiments, the arc has an angular length between approximately 180° and approximately 200°. In some embodiments, the area covered by the aversive coating is on the outer surface of the negative terminal.
[0009] In some embodiments, the electrochemical cell is a coin-shaped or button-shaped cell, and the total area coated with the aversive coating is approximately 10 mm². 2 ~approximately 100mm2 In some embodiments, the electrochemical cell is a coin-type cell, and the total area coated with the deterrent coating is from about 20 mm 2 to about 50 mm 2 In some embodiments, the electrochemical cell is a coin-type cell, and the total area coated with the deterrent coating is about 33.9 mm 2 In some embodiments, the total amount of the deterrent is from about 10 μg to about 30 μg. In some embodiments, the deterrent coating has a thickness of from about 5 μm to about 15 μm. In some embodiments, the electrochemical cell is packaged in child-resistant packaging.
[0010] Various embodiments provide a method for fabricating an electrochemical cell coated with a deterrent coating. The method includes preparing a coating solution comprising a deterrent composition of 0.2 wt% to 20 wt% and a water-soluble polymer of 0.2 wt% to 14 wt% dissolved in one or more solvents, applying the coating solution to 2% to 50% of the area of the outer surface of the terminals of the electrochemical cell, and drying the solution on the area of the outer surface of the terminals of the electrochemical cell. In some embodiments, the coating solution is prepared by dissolving a deterrent of 0.2 wt% to 2.0 wt% in one or more solvents. In some embodiments, the coating solution is prepared by dissolving an adhesion promoter of 0.01 wt% to 3.0 wt% in one or more solvents.
[0011] In some embodiments, the coating solution is prepared by heating PVA in water to about 95 °C for about 60 minutes to dissolve it before adding a solution containing dissolved Lubrizol 2063. In some embodiments, the solution containing dissolved PVA is cooled before adding the deterrent composition. In some embodiments, the coating solution is prepared by dissolving 0.2% to 18% by mass of a colorant in one or more solvents. In some embodiments, the coating solution is prepared by dissolving within a range of 0.01 mass% to 0.3 mass% of a surfactant in one or more solvents. In these embodiments, the coating solution within a range of 0.01 mass%-2.0 mass% of a viscosity modifier solution is prepared by dissolving in one or a plurality of solvents.
[0012] In some embodiments, the coating solution is prepared by dissolving about 10% by mass of PVA, about 1.5% by mass of DNB, about 12% by mass of FD&C Blue No. 1, about 1.0% by mass of Lubrizol 2063, and about 0.1% of SDS in one or more solvents. In some embodiments, the method of fabricating an electrochemical cell further includes masking one or more portions of the electrochemical cell before applying the coating solution. In some embodiments, the method of fabricating an electrochemical cell further includes cleaning the outer surface of the electrochemical cell prior to the step of applying the coating solution. 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 "examples") according to the present disclosure.
Brief Description of the Drawings
[0013] [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 5]This shows an electrochemical coin-shaped cell containing an aversive coating applied as dots within an arc shape on the negative electrode terminal. [Figure 6] The dimensions of the aversive coating applied to the negative electrode terminal of the electrochemical cell are shown. [Figure 7] Two rectangular patterns are shown for applying an aversive coating to the terminals of an electrochemical coin cell. [Figure 8] This shows a pattern of broken circles for applying an aversive coating to the terminals of an electrochemical coin cell. [Figure 9] An example of child-resistant packaging 600 according to one embodiment is shown. [Modes for carrying out the invention]
[0014] Detailed explanation Coin cell batteries, also known as button cells, are small, single-cell batteries typically used to power low-power devices such as watches, calculators, hearing aids, and small electronic devices. Their small size and compact size make them easy to use and store, and they are available in a wide variety of sizes, chemical properties, and voltage ratings. Coin cell batteries were initially developed for use in hearing aids, but are now used in a variety of other applications and devices, including watches, calculators, and other small electronic devices. A coin cell battery typically consists of a positive electrode (cathode), a negative electrode (anode), and an electrolyte that allows for 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.
[0015] 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 chemical properties and rated voltage of the battery. For example, in a manganese dioxide-based cylindrical cell, 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 supply 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.
[0016] 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.
[0017] 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).
[0018] 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.
[0019] 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.
[0020] 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).
[0021] 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) is 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
[0022] 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
[0023] 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)
[0024] 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
[0025] 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. 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).
[0026] 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.
[0027] 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.
[0028] 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.
[0029] 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. 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.
[0030] 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. 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.
[0031] 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. 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. Where used throughout this specification, duplex stainless steel refers to duplex steel exhibiting both ferritic and austenitic crystal structures. References to specific grades should be presumed to refer to standards published by ASTM International unless other references known to those skilled in the art of metallurgy are indicated in the context.
[0032] 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 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.
[0033] 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 an 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 6.1% 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.
[0034] 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.
[0035] 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%.
[0036] In some embodiments, one or more additives to the aversive coating include an adhesion promoter. The addition of an adhesion promoter may help the aversive coating adhere better to the surface of the electrochemical cell. 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 from 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 contains about 4.1% by mass of Lubrizol 2063.
[0037] In some embodiments, one or more additives to the aversive coating include a surfactant. The surfactant can reduce the surface tension of the solution and act as a wetting and dispersing agent to assist in the application of the aversive coating to the electrochemical cell. In some embodiments, the dry mass composition of the aversive coating includes 0.01% to about 1.0% 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.
[0038] In some embodiments, one or more additives to 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).
[0039] 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.
[0040] 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 35% to about 45% 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.
[0041] 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. 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.
[0042] Electrochemical cell Aspects of this disclosure relate to an electrochemical cell coated with the anti-hatred coating 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 coated with the anti-hatred coating described 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.
[0043] In some embodiments, 2% to 50% of the positive and / or negative terminals, 3% to 50% of the positive terminals, 3% to 40% of the negative terminals, 3% to 30% of the positive and / or negative terminals are coated with an aversive coating. In some embodiments, approximately 6.7% of the negative terminals are coated with an aversive coating. In some embodiments, approximately 13% of the negative terminals are coated with an aversive coating. In some embodiments, approximately 15% of the negative terminals are coated with an aversive coating. In some embodiments, approximately 16% of the negative terminals are coated with an aversive coating.
[0044] Figure 5 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, rhombuses, triangles, semicircles, or crescent shapes 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 aversive coating is not located on the sidewall 24 of the gasket 30. The sidewall 24 of the gasket 30 is shown in Figures 2 and 3. In some embodiments, the aversive coating is located on the positive terminal. The outer surface 25 of the positive terminal 20 is shown in Figures 2 and 3. In some embodiments, the aversive coating is located on the negative electrode terminal. The outer surface 17 of the negative electrode terminal 12 is shown in Figures 2 and 3. In some embodiments, the region of the positive and / or negative terminal coated with the anti-hatrous coating is arc-shaped or annular with an outer diameter of approximately 14 mm and an inner diameter of approximately 8.2 mm, and the arc or annular is centered relative to the terminal.
[0045] In some embodiments, the aversive coating is applied as multiple dots within an arc-shaped, annular, semicircular, or crescent-shaped area on the positive and / or negative terminals. In some embodiments, the dots have a diameter of approximately 0.7 mm to approximately 1.0 mm. In some embodiments, the area of the positive and / or negative terminals coated with the aversive coating includes multiple sub-arcs or sub-rings. In some embodiments, the area of the positive and / or negative terminals coated with the aversive coating includes 2, 3, 4, or 5 sub-arcs or sub-rings. In some embodiments, the aversive coating is applied as an arc having an angular length α between an arc of approximately 90° and an arc of approximately 270°. In some embodiments, as shown in Figure 5, the angular length is an arc of approximately 200°. In some embodiments, the angular length is an arc of approximately 180°. In some embodiments, the angular length is an arc less than 220°, less than 210°, less than 200°, less than 190°, or less than 180°. The "angle length" of an arc refers to the angle measured from one end of the arc to the center of the terminal and then to the other end of the arc. For example, an angle length of 360° constitutes a closed circle. An angle length of 90° covers one-quarter of the circle, and an angle length of 180° covers half of the circle.
[0046] In some embodiments, the aversive coating is applied as one or more rectangles. In some embodiments, the aversive coating is applied to two rectangular regions 71 spanning the positive and / or negative terminals, as shown in Figure 7. In some embodiments, the length 72 of each rectangular region is approximately 12.5 mm. In some embodiments, the width 73 of each rectangular region is approximately 2 mm. In some embodiments, each rectangle is located approximately 4 mm from the center of the terminal. In some embodiments, the aversive coating is applied to a broken circle, and as shown in Figure 8, the aversive coating covers an annular region 74 with a gap 75 on the positive and / or negative terminals that is not coated. In some embodiments, the broken circle has an outer diameter 76 of about 17.5 mm. In some embodiments, the width 77 of the broken circle is about 0.8 mm. In some embodiments, the aversive coating is applied to about 50% of the circumference of the broken circle (for example, about 50% of the ring has the aversive coating and the gap constitutes the remaining 50%).
[0047] 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. For sufficient aversive properties, at least 1 μg of aversive taste agent is applied to each electrochemical cell. In some embodiments, the total amount of aversive taste agent applied to the electrochemical cell is between 1 μg and 120 μg, between 1 μg and 50 μg, between 4 μg and 120 μg, between 5 μg and 100 μg, between 5 μg and 50 μg, between 5 μg and 40 μg, between 5 μg and 30 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 taste agent applied to the electrochemical cell is about 25 μg.
[0048] In some embodiments, the electrochemical cell is a coin-shaped or button-shaped cell, and the total area covered with the aversive coating is approximately 10 mm². 2 ~approximately 100mm 2 In some embodiments, the electrochemical cell is a coin-shaped cell, and the total area covered with the aversive coating is approximately 20 mm². 2 ~approximately 50mm 2In some embodiments, the electrochemical cell is a coin-shaped cell, and the total area covered with the aversive coating is approximately 30 mm². 2 ~40mm 2 In some embodiments, the total area coated with the aversive coating is approximately 33.9 mm². 2 That is the case. In some embodiments, the electrochemical cell is a button-shaped cell, and the total area coated with the aversive coating is approximately 10 mm². 2 ~approximately 50mm 2 That is the case. The aversive coating may be a thicker layer if applied to specific locations in the device that do not interfere with the use of the battery. In some embodiments, the aversive coating is about 5 μm to about 15 μm thick, or about 8 μm to about 12 μm thick. In some embodiments, the aversive coating is about 10 μm thick.
[0049] In some embodiments, the electrochemical cells are packaged for sale in child-resistant packaging. While the embodiment in Figure 9 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.
[0050] 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 9, 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.
[0051] 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 comprises 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 at least a portion of the outer surface of an electrochemical cell, and drying the solution on that portion of the outer surface of 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.
[0052] In some embodiments, the coating solution is prepared by dissolving about 10% 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 10% 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 10% 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.
[0053] 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.
[0054] The outer surface of the electrochemical cell may be cleaned after manufacturing as part of a pretreatment process 200, prior to step 300 in which the coating solution is applied. Removing grease or residue from the manufacturing process 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. The entire outer surface of the electrochemical cell can be cleaned. 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. Aversive coatings can be applied to electrochemical cells using any method known in the art. In some embodiments, the coating solution is applied to the electrochemical cell by immersion, spraying, printing, or dispensing. 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 specific portions of the electrochemical cell. The mask can be removed after the aversive coating has dried. [Examples]
[0055] Examples As discussed herein, bittering agents, colorants, salivary gland stimulants, 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 odors, such as spiciness, pepperiness, sourness, bitterness, or malodourity. Examples include capsaicin, allyl isothiocyanate, and piperine. For example, one or more aversive agents may be added to a coating that adheres to the outer surface of the battery. In one embodiment, a water-soluble polymer such as polyvinyl alcohol (PVA) is added to a water-based aversive agent solution so that the aversive agent is encapsulated in the PVA network when applied to the battery surface. As the water evaporates from the solution, the polymer acts as a binder, binding the aversive agent (and / or other active substances such as colorants and / or salivary gland stimulants) to the battery surface. However, since the coating remains soluble in water (or water-like solutions such as saliva), if a person (e.g., a child) puts the battery in their mouth, the aversive agent is released from the surface of the battery. The unpleasant taste of aversive agents can cause people to spit out batteries rather than swallow them.
[0056] In certain embodiments, the PVA coating (or other polymer adhesive) is thin enough to allow for an electron tunneling effect. As a result, the resulting coating does not affect the normal function of the battery. However, in embodiments where the PVA coating is applied to the central portion of the battery terminals and to portions of the cell that are not aligned, the coating may be thicker, and therefore, electron tunneling is not necessary. For water-soluble polymers such as, but not limited to, PVA and polyacrylic acid (PAA), the upper limit of the amount of polymer used (e.g., the thickness of the resulting polymer coating) is the amount of polymer that maintains conductivity on the outer surface of the battery. For example, the thickness may be less than 10 μm. However, if the battery terminals are left exposed (uncoated), the thickness of the coating may be greater on those parts of the cell coated with the polymer and active substance solution.
[0057] The lower limit of the amount of polymer used is the amount of polymer that binds appropriately with the aversive agent (e.g., denatonium benzoate (DNB), but other colorants or salivary gland stimulants may be incorporated). The range of PVA is approximately 0.2% to 14% when applied as a wetting formulation. The dry mass composition of the aversive coating is approximately 5% to 98.5% PVA. The polymer may be a low molecular weight polymer (1 to 10 K), a medium molecular weight polymer (10 to 100 K), or a high molecular weight polymer (>100 K). 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 a stronger degree of chain entanglement, forming films with high tensile strength. High molecular weight polymers also tend to form tougher and more chemically resistant materials. Furthermore, the viscosity of the solution containing the polymer increases with increasing molecular weight. Medium molecular weight polymers have moderate water solubility, strength, and viscosity. By selecting a polymer of an appropriate size containing additives such as adhesion promoters, surfactants, and viscosity modifiers, an aversive coating that adheres well to the surface of an electrochemical cell can be formed. The amount of aversive agent can be selected to produce an undesirable 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) for each coin-type cell.
[0058] 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.
[0059] The coating may be applied to any of the various locations on the outer surface of the battery. The coating layer is colorless and, when applied uniformly, is almost invisible. The aversive coating may be applied as multiple dots on the surface of the terminals. The aversive coating may also be applied as one or more rectangles across the entire terminal. The shape of the aversive coating may be an arc, a ring, or a broken circle (e.g., a ring with a gap) on the terminal. The coating solution can be deposited on the electrochemical cell in the desired shape using methods such as inkjet, screen printing, pad printing, stamping, needle ejection, and spraying. 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.
[0060] 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 polymer binder (e.g., PVA, PAA, polyethylene glycol, polyacrylamide, and / or similar); any viscosity modifier for better processing (e.g., carboxymethylcellulose (CMC)). The coating may be applied by spraying. The polymer binder may be provided in the coating solution in an amount between about 0.00001% by mass and 14% by mass. For example, an amount between about 0.2% by mass and 14% by mass, more specifically, an amount between about 11% by mass and 13% by mass. In certain embodiments, the colorant may be provided in the solution in an amount between about 0.01% by mass and 18% by mass. The viscosity modifier (e.g., thickener) may be provided in the solution in an amount between about 0% by mass and 2% by mass. The aversive agent (e.g., DNB) may be provided in an amount between about 0.01% by mass and 2% by mass (e.g., about 1.0% by mass and 2.0% by mass) of the solution.
[0061] Before coating, the battery may be washed for a total of 8 seconds at 30°C using, for example, deionized water (e.g., periodically treated deionized water with conductivity σ < 10 μS / cm). 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. To selectively apply the aversive coating solution to specific areas of the terminals, a mask (e.g., a solid, non-absorbent material with gaps of a desired shape) may be placed on the electrochemical cell. For example, after manufacturing and cleaning, and before applying the coating solution, a mask such as a plastic sheet with two rectangular holes may be placed on top of the coin-shaped cell to generate the coating in the pattern shown in Figure 7. The coating may be sprayed onto the cleaned cell surface approximately 1 second after natural drying is complete. The cell may then be dried (e.g., 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.
[0062] By spraying the coating material onto specific parts of the cell, the conductivity of the cell can be maintained even if the thickness of the coating hinders electron transfer through the coating. In other words, if the coating is placed on parts of the cell where conductivity is not required, the coating does not need to be thin enough to maintain conductivity. If a thick coating layer is provided on some parts of the battery, while other uncoated parts of the battery are left uncoated, the total load of aversive agents (e.g., bittering agents) on the battery can be increased. However, if the coating is sprayed onto the cell terminals, the coating may be thin enough so that its dry thickness maintains conductivity through the coating (e.g., due to the electron tunneling effect).
[0063] For example, the coating may be applied to the positive and / or negative terminals of a battery. The coating may be applied to a portion of the positive and / or negative terminals, leaving the rest of the terminals exposed. As a non-limiting example, the coating may be applied in a circular configuration centered on the positive and / or negative terminals, with the center of the circle not being coated. As another example, one or more stripes of coating material may be provided on the positive and / or negative terminals, with these stripes (e.g., linear or non-linear stripes) offset from the center of the positive and / or negative terminals (i.e., the center of the terminals not being coated). The stripes are approximately 12.5 mm long, 2 mm wide, and 25 mm in area. 2 It may also be a rectangle. The electrochemical cell has two rectangles on the negative electrode terminal, as shown in Figure 7, with a total area of approximately 50 mm². 2 We can provide an aversive coating. In the case of a coin-shaped cell with an outer diameter of 20 mm, approximately 16% of the area of the negative terminal is covered with the aversive coating.
[0064] The electrochemical cell may also have one or more curved stripes around the edge of the negative electrode terminal. The curved stripes may be about 0.8 mm wide and 17.5 mm in outer diameter. In some cases, the curved stripes may have an area of about 41.9 mm². 2 This forms a ring, providing a negative electrode terminal in a coin-shaped cell with an outer diameter of 20 mm, where approximately 13% of the area is covered with the aversive coating. Furthermore, the electrochemical cell may form a circular pattern with multiple curved stripes, as shown in Figure 8. The circular pattern has the same width and outer diameter as the ring pattern, but two or more gaps may lack the aversive coating (five gaps are shown in Figure 8). In some cases, approximately 50% of the periphery of the circular pattern is coated with the aversive coating, and the remaining 50% of the periphery is a gap without the aversive coating. This results in approximately 21 mm for a coin-shaped cell with an outer diameter of 20 mm. 2 The entire surface area is covered with the aversive coating, and approximately 6.7% of the negative terminal area is covered with the aversive coating.
[0065] In certain embodiments, the coating may be provided in an arc shape on the positive and / or negative terminals. In certain embodiments, the coating may be provided as a plurality of dots on the positive and / or negative terminals, as shown in Figure 5. In certain embodiments, the cell may have coatings of varying thicknesses, so that the parts of the cell that do not affect use in the device have a thicker coating, while the other parts of the cell have a thinner coating to maintain conductivity through the coating. In areas where the coating does not affect use in the device, the coating may be about 8 μm to about 12 μm thick. This thin coating, which has minimal impact on the battery performance in the device, may be less than 1 μm thick.
[0066] conclusion Many modifications to the embodiments described herein will be recalled by those skilled in the art to whom these embodiments relate, and who have an interest in the teachings shown in the foregoing description and the associated 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 associated 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 only in a general and descriptive sense and are not intended to be limiting.
[0067] 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.
[0068] 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, A negative terminal that is electrically insulated from the positive terminal and defines a second portion of the outer surface of the electrochemical cell, An anode, which is placed inside the electrochemical cell and electrically connected to the negative electrode terminal, A cathode disposed inside the electrochemical cell, which is electrically isolated from the anode and electrically connected to the positive terminal, An aversive coating covering 2% to 50% of the outer surface area of at least one terminal of an electrochemical cell, Aversive agent compositions in an amount of 0.5% to 65% by mass, and 5% to 98.5% by mass of water-soluble polymer A negative coating having a dry mass composition including 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 one or more of the additives include 0.1% by mass to 5.0% by mass of an adhesion promoter.
6. The electrochemical cell according to claim 5, wherein the adhesion promoter is Lubrizol 2063.
7. The electrochemical cell according to claim 1, wherein the one or more additives include a surfactant in an amount of 0.01% to 1.0% by mass.
8. The electrochemical cell according to claim 7, wherein the surfactant is sodium dodecyl sulfate (SDS).
9. The electrochemical cell according to claim 1, wherein one or more of the additives include a viscosity modifier in an amount of 0.01% to 2.0% by mass.
10. The electrochemical cell according to claim 9, wherein the viscosity modifier is carboxymethylcellulose (CMC).
11. The electrochemical cell according to claim 1, wherein the aversive agent composition comprises 0.5% to 60% by mass of a coloring agent based on the mass of the aversive coating.
12. The electrochemical cell according to claim 11, 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.
13. The electrochemical cell according to claim 12, wherein the coloring agent is FD&C Blue No.
1.
14. The aforementioned aversive coating Approximately 5.0% to 7.0% by mass of denatonium benzoate, Approximately 35% to 45% by mass of PVA, Approximately 45% to 55% by mass of FD&C Blue No. 1 The electrochemical cell according to claim 13, including the following:
15. The electrochemical cell according to claim 14, wherein the aversive coating further comprises about 2.0% by mass to about 5.0% by mass of Lubrizol 2063.
16. The electrochemical cell according to claim 14, wherein the aversive coating further comprises about 0.4% SDS.
17. The electrochemical cell according to claim 1, which is a button-shaped cell or a coin-shaped cell.
18. The electrochemical cell according to claim 17, wherein the aversive coating is located on the outer surface of the terminal, approximately 14 mm in diameter inward from the center of the terminal.
19. The electrochemical cell according to claim 17, wherein the aversive coating is located on the outer surface of the terminal, approximately 8.2 mm in diameter from the center of the terminal.
20. The electrochemical cell according to claim 18 or 19, wherein the region of the outer surface of the terminal coated with the anti-averse coating has a shape including one or more of the following: stripes, circles, rings, arcs, ellipses, squares, rectangles, rhombuses, triangles, semicircles, or crescent shapes.
21. The electrochemical cell according to claim 20, wherein the aversive coating is provided in an arc shape on the outer surface of the terminal, the outer diameter of the arc is approximately 14 mm, the inner diameter of the arc is approximately 8.2 mm, and the arc is centered relative to the terminal.
22. The electrochemical cell according to claim 20, wherein the aversive coating is provided in an annular shape on the outer surface of the terminal, the outer diameter of the arc is approximately 14 mm, the inner diameter of the arc is approximately 8.2 mm, and the ring is centered relative to the terminal.
23. The electrochemical cell according to claim 21, wherein the arc is between an arc with an angular length of approximately 90° and an arc with an angular length of approximately 270°.
24. The electrochemical cell according to claim 23, wherein the arc has an angular length between an arc of approximately 180° and an arc of approximately 200°.
25. The electrochemical cell according to claim 17, wherein the region covered by the aversive coating is located on the outer surface of the negative electrode terminal.
26. The total area coated with the aforementioned aversive coating is approximately 10 mm². 2 ~approximately 100 mm 2 The electrochemical cell according to claim 17.
27. The electrochemical cell is a coin-shaped cell, and the total surface area coated with the aversive coating is approximately 20 mm². 2 ~approximately 50mm 2 The electrochemical cell according to claim 26.
28. The electrochemical cell according to claim 17, wherein the total amount of the aversive coating applied to the electrochemical cell is about 0.1 mg to about 1.2 mg.
29. The electrochemical cell according to claim 17, wherein the total amount of the aversive taste agent is about 10 μg to about 30 μg.
30. The electrochemical cell according to claim 17, wherein the aversive coating has a thickness of about 5 μm to about 15 μm.
31. The electrochemical cell according to claim 1, packaged in child-resistant packaging.
32. A method for preparing a child-safe electrochemical cell, wherein 2% to 50% of the outer surface area of at least one terminal of the electrochemical cell is coated with an aversive coating, the aversive coating having 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, and the method is as follows: A step of preparing a coating solution, wherein the coating solution comprises 0.2% to 20% by mass of an aversive agent composition dissolved in one or more solvents and 0.2% to 14% by mass of a water-soluble polymer, The steps include applying the coating solution to 2% to 50% of the area of the outer surface of the terminals of the electrochemical cell, A step of drying the solution on the surface area of the outer surface of the terminals of the electrochemical cell. Methods that include...
33. The aversive agent composition comprises at least one aversive taste agent selected from denatonium benzoate (DNB), capsaicin, allyl isothiocyanate, or piperine. The method according to claim 32, wherein the coating solution contains 0.2% by mass to 2.0% by mass of the aversive taste agent.
34. The method according to claim 32, wherein the coating solution further comprises 0.01% by mass to 3.0% by mass of an adhesion promoter.
35. The method according to claim 34, wherein the water-soluble polymer is PVA, the adhesion promoter is Lubrizol 2063, and the PVA is dissolved by heating to about 95°C for about 60 minutes before adding the solution containing dissolved Lubrizol 2063.
36. The method according to claim 35, wherein the step of preparing the coating solution further comprises cooling the PVA before adding the aversive taste agent.
37. The method according to claim 32, wherein the step of preparing the coating solution further comprises dissolving 0.2% to 18% by mass of a coloring agent in the coating solution.
38. The method according to claim 32, wherein the step of preparing the coating solution further comprises dissolving 0.01% to 0.3% by mass of a surfactant in the coating solution.
39. The method according to claim 32, wherein the step of preparing the coating solution further comprises dissolving 0.01% to 2.0% by mass of a viscosity modifier in the coating solution.
40. The aforementioned coating solution Approximately 1.5% by mass of DNB, Approximately 10% by mass of PVA, Approximately 12% by mass of FD&C Blue No. 1, Approximately 1.0 mass% of Lubrizol 2063, and Approximately 0.1% by mass of SDS The method according to claim 32, including the method described in claim 32.
41. The method according to claim 32, further comprising cleaning the outer surface of the electrochemical cell before the step of applying the coating solution.