Button cell comprising titanium-based contact material with improved cold formability for safer button cell

Abstract

More secure button cells and materials with improved cold moldability for making contacts of the button cells are described. A titanium-based material may be used having > = 95 wt.% titanium, < = 0.5 wt.% iron, < = 0.5 wt.% oxygen, < = 0.5 wt.% carbon, < = 0.5 wt.% nitrogen, and < = 0.5 wt.% hydrogen. Contact points made of such materials are resistant to reactions that form hydroxides upon contact with bodily fluids (e.g., after ingestion). The titanium-based material has improved cold formability at room temperature, which reduces or eliminates microcracks during contact forming. The reduced or eliminated microcracks reduce or eliminate alkalization reactions that would otherwise occur when conventional button cells are in contact with bodily fluids.

Description

Technical Field

[0001] This invention relates to button batteries, and more particularly to materials and coatings for cans, terminals, and contacts of button batteries, and even more particularly to materials and coatings for positive cans, terminals, and contacts of button batteries that reduce or eliminate hydroxide formation when the button battery comes into contact with bodily fluids, and even more particularly to materials that exhibit improved cold formability to avoid microcracks in the material during the forming of the positive can, terminal, or contact of the button battery. Background Technology

[0002] Button batteries or button battery packs (also known as coin batteries or coin battery packs), such as those described in International Patent Publication No. PCT / US2013 / 021430 filed January 14, 2013 (the contents of which are incorporated herein by reference in their entirety), are small, disc-shaped batteries commonly used in a wide range of electronic devices, such as hearing aids, cochlear implant processors, calculators, remote controls, and watches. These batteries and battery packs are commonly referred to as button batteries due to their shape and size.

[0003] Children who accidentally ingest button batteries can suffer acute injuries and even death, partly due to the electrolytic reaction that occurs when the battery's current comes into contact with bodily fluids such as tissue fluid, mucus, esophageal lining fluid, and gastric juice, producing hydroxide (high pH) on the negative electrode. The resulting hydroxide can cause alkali burns and esophageal perforation. Severe injuries can occur within just two hours.

[0004] To address this issue, some button batteries have incorporated one or more anti-swallowing features. For example, an anti-swallowing feature is a raised border around the perimeter of the battery pack. This raised border makes it difficult for children to swallow the battery pack. Other anti-swallowing features include a bitter coating on the battery surface, which prevents children from putting the battery in their mouths. However, if swallowed, button or coin batteries coated with a bitter agent or with a raised, rounded perimeter can still cause an electrolytic reaction in the esophagus or stomach and result in serious damage. Invention Overview

[0006] Various embodiments relate to button batteries and button battery packs, and particularly to button battery packs comprising contact materials with improved cold formability for safer button battery packs.

[0007] This invention describes a titanium-based strip with improved cold formability as a positive electrode can for safer button batteries / battery packs. The button battery positive electrode can is made of a titanium-based strip having ≥95 wt% titanium, ≤0.5 wt% iron, ≤0.5 wt% oxygen, ≤0.5 wt% carbon, ≤0.5 wt% nitrogen, and ≤0.5 wt% hydrogen. The contact is resistant to alkalization or electrolytic reactions that occur when the button battery is ingested and comes into contact with certain bodily fluids. The titanium-based strip has improved mechanical properties, such as improved cold formability. When a bend with a radius of approximately 100% to approximately 500% of the thickness of the titanium-based strip is formed in the titanium-based strip during the positive electrode can forming process, for example, a bend radius equal to or less than approximately 150% of the thickness of the titanium-based strip, the titanium-based strip material exhibits reduced or no microcracks. The reduction or elimination of microcracks reduces or eliminates the occurrence of alkalization or electrolysis reactions in conventional button cells using positive electrode can materials that exhibit microcracks during the positive electrode can molding process.

[0008] According to one embodiment, a casing is provided configured for an electrochemical coin cell, the casing comprising: a housing having a flat wall and sidewalls, the sidewalls extending from one or more edges of the flat wall of the housing to form a housing can; and a planar conductive portion engaged with the sidewall of the housing to form an inner cavity configured to receive an active component of the electrochemical coin cell, wherein the housing or the planar conductive portion comprises more than about 95% by weight of titanium, and wherein the radius of curvature between the flat wall and the sidewall of the housing is less than or equal to about 150% of the thickness of the housing metal or the planar conductive portion. As described in other parts of this disclosure, the radius of curvature can be measured using, for example, ASTM Test Method E290, “Test Methods for Bend Testing of Materials for Ductility”. The term “bend radius” is used herein to describe the bend radius, minimum bend radius, maximum bend radius, or average bend radius of a material / strip (such as titanium-based strip) when formed into a can, terminal, or other part of a button cell. “Bend radius” is also used herein to describe the bend radius, minimum bend radius, maximum bend radius, or average bend radius that can be applied to a material / strip (such as titanium-based strip) where no or substantially no microcracks or other bend-related damage are formed at or near the bend, as measured, for example, according to ASTM Test Method E290.

[0009] In some embodiments, the housing or planar conductive portion comprises more than about 99 wt% titanium. In some embodiments, the housing or planar conductive portion comprises less than about 0.5 wt% iron, less than about 0.5 wt% oxygen, less than about 0.5 wt% carbon, less than about 0.5 wt% nitrogen, and less than about 0.5 wt% hydrogen. In some embodiments, the housing or planar conductive portion comprises about 0.3 wt% iron, about 0.25 wt% oxygen, about 0.1 wt% carbon, about 0.03 wt% nitrogen, and about 0.015 wt% hydrogen. In some embodiments, the housing or planar conductive portion has an ultimate tensile strength of about 35,000 psi to about 60,000 psi. In some embodiments, the housing or planar conductive portion has an elongation at break of about 10% to about 50%. In some embodiments, the housing or planar conductive portion has an elastic modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the housing or planar conductive portion has a compressive modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the housing or planar conductive portion has a shear modulus of about 4,000 ksi to about 10,000 ksi. In some embodiments, the housing or planar conductive portion has a Poisson's ratio of about 0.25 to about 0.40. In some embodiments, the housing or planar conductive portion has a compressive modulus of about 50 ksi-in. 1 / 2 Up to approximately 65 ksi-in 1 / 2 Annealed fracture toughness. In some embodiments, the housing or planar conductive portion has an elongation greater than about 20% (e.g., about 20% to about 50%) at room temperature (e.g., about 21°C). In some embodiments, the housing or planar conductive portion has a resistivity of about 40 μΩ·cm to about 100 μΩ·cm.

[0010] In some embodiments, when engaged with the sidewall of the housing, the outer peripheral portion of the planar conductive portion bends outward from the plane of the remaining portion of the planar conductive portion by approximately 90 degrees to approximately 270 degrees. In some embodiments, one or more of the housing or the planar conductive portion includes a surface portion comprising one or more of the following: TiN, Ti₂N, or TiC. In some embodiments, one or more of the housing or the planar conductive portion includes a surface coating comprising nickel. In some embodiments, the housing or the planar conductive portion comprises a material resistant to reactions that lead to the formation of hydroxides.

[0011] According to another embodiment, an electrochemical button cell can be provided, comprising: a cylindrical casing including a positive electrode contact surface and sidewalls circumferentially formed around the positive electrode contact surface, wherein the cylindrical casing defines an inner volume; an anode material disposed within a first portion of the inner volume; a cathode material disposed within a second portion of the inner volume; a separator disposed within the inner volume between the anode material and the cathode material; an electrolyte material disposed within the inner volume and configured to transport ions between the anode material and the cathode material; and a negative electrode contact surface disposed within or adjacent to the inner volume such that the anode material, cathode material, separator, and electrolyte material are encapsulated within the inner volume, wherein a portion of the sidewalls engages with an edge of the planar negative electrode contact surface to seal the inner volume of the cylindrical casing. In some embodiments, the thickness of the negative electrode contact surface is from approximately 0.1 mm to approximately 0.5 mm.

[0012] In some embodiments, the titanium-containing material comprises more than about 95% by weight of titanium. In some embodiments, the titanium-containing material comprises more than about 99% by weight of titanium. In some embodiments, the titanium-containing material comprises less than about 0.5% by weight of iron, less than about 0.5% by weight of oxygen, less than about 0.5% by weight of carbon, less than about 0.5% by weight of nitrogen, and less than about 0.5% by weight of hydrogen. In some embodiments, the titanium-containing material comprises about 0.3% by weight of iron, about 0.25% by weight of oxygen, about 0.1% by weight of carbon, about 0.03% by weight of nitrogen, and about 0.015% by weight of hydrogen.

[0013] In some embodiments, the titanium-containing material has an ultimate tensile strength of about 40,000 psi to about 60,000 psi. In some embodiments, the titanium-containing material has an elongation at break of about 10% to about 50%. In some embodiments, the titanium-containing material has an elastic modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the titanium-containing material has a compressive modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the titanium-containing material has a shear modulus of about 4,000 ksi to about 10,000 ksi. In some embodiments, the titanium-containing material has a Poisson's ratio of about 0.25 to about 0.40. In some embodiments, the titanium-containing material has a tensile strength of about 50 ksi-in. 1 / 2 Up to approximately 65 ksi-in 1 / 2 The annealed fracture toughness is high, and in some embodiments, the titanium-containing material has a resistivity of about 40 μΩ·cm to about 100 μΩ·cm.

[0014] In some embodiments, the negative electrode contact surface comprises stainless steel. In some embodiments, the negative electrode contact surface comprises a metal-clad stainless steel material.

[0015] In some embodiments, after the edges of the planar negative electrode contact surface are bent and the negative electrode contact surface is bonded to a portion of the sidewall of the cylindrical housing to seal the electrochemical button cell, when the outer surface of the planar negative electrode contact surface of the electrochemical button cell is exposed to bodily fluids, substantially no hydroxide is formed in the subsequent period (e.g., 480 minutes).

[0016] According to another embodiment, an electrochemical button cell can be provided, comprising: an active electrochemical assembly including an anode, a separator, and a cathode, wherein the active electrochemical assembly generates an output open-circuit voltage of at least 2.8 volts in the presence of a non-aqueous electrolyte; and a cylindrical container encapsulating the active assembly, the cylindrical container including an anode terminal housing and a cathode terminal housing, with an electrically insulating gasket disposed between them, the anode terminal housing being electrically connected to the anode, and the cathode terminal housing being electrically connected to the cathode. In some embodiments, the cathode terminal housing is composed of a first material that is resistant to the reaction of producing hydroxides during exposure to bodily fluids. In some embodiments, the anode terminal housing is composed of a second material different from the first material. In some embodiments, the first material contains more than about 99% by weight titanium. In some embodiments, a circumferential edge portion of the anode terminal housing is bent or rolled to attach the cathode terminal housing to the cylindrical container. In some embodiments, a circumferential edge portion of the cathode terminal housing is bent or rolled to attach the anode terminal housing to the cylindrical container.

[0017] In some embodiments, the composition of the first material differs from that of the second material. In some embodiments, the second material comprises stainless steel. In some embodiments, the first material comprises less than about 0.5 wt% iron, less than about 0.5 wt% oxygen, less than about 0.5 wt% carbon, less than about 0.5 wt% nitrogen, and less than about 0.5 wt% hydrogen. In some embodiments, the first material comprises about 0.3 wt% iron, about 0.25 wt% oxygen, about 0.1 wt% carbon, about 0.03 wt% nitrogen, and about 0.015 wt% hydrogen.

[0018] In some embodiments, the first material has an ultimate tensile strength of about 40,000 psi to about 60,000 psi. In some embodiments, the first material has an elongation at break of about 10% to about 50%. In some embodiments, the first material has an elastic modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the first material has a compressive modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the first material has a shear modulus of about 4,000 ksi to about 10,000 ksi. In some embodiments, the first material has a Poisson's ratio of about 0.25 to about 0.40. In some embodiments, the first material has a strength of about 50 ksi-in 1 / 2 Up to approximately 65 ksi-in 1 / 2 Annealed fracture toughness. In some embodiments, the first material has a resistivity of about 40 μΩ·cm to about 100 μΩ·cm.

[0019] According to another embodiment, a method for manufacturing or forming a casing for an electrochemical coin cell can be implemented. In some embodiments, the method includes: forming a first contact surface for the electrochemical coin cell from a first sheet composed of a first material containing more than about 99% by weight titanium; forming a cylindrical casing cup from a second sheet composed of a second material, the cylindrical casing cup including a substantially flat bottom and sidewalls circumferentially formed around the substantially flat bottom, the substantially flat bottom forming a second contact surface for the electrochemical coin cell, the substantially flat bottom and the sidewalls forming an inner volume; disposing an active electrochemical component within the inner volume of the cylindrical casing cup, the active electrochemical component including an anode, a separator, and a cathode, wherein the active electrochemical component is configured to generate an output open-circuit voltage of at least 2.8 volts in the presence of a non-aqueous electrolyte; and sealing the active electrochemical component within the inner volume of the electrochemical coin cell by engaging the circumferential edge of the first contact surface to one or more portions of the sidewalls of the cylindrical casing cup to electrically communicate the first and second contact surfaces with the active electrochemical component. In some embodiments, the circumferential edge of the first contact surface is engaged to one or more portions of the sidewall of the cylindrical housing cup by bending or curling the circumferential edge of the first contact surface or one or more portions of the sidewall of the cylindrical housing cup.

[0020] In some embodiments, the dimensions and configuration of the first contact surface composed of the first material are such that it is resistant to reactions that produce hydroxides upon exposure to bodily fluids. In some embodiments, the first material is different from the second material. In some embodiments, the second material comprises stainless steel. In some embodiments, the first material contains less than about 0.5 wt% iron, less than about 0.5 wt% oxygen, less than about 0.5 wt% carbon, less than about 0.5 wt% nitrogen, and less than about 0.5 wt% hydrogen. In some embodiments, the first material contains about 0.3 wt% iron, about 0.25 wt% oxygen, about 0.1 wt% carbon, about 0.03 wt% nitrogen, and about 0.015 wt% hydrogen.

[0021] In some embodiments, the first material has an ultimate tensile strength of about 40,000 psi to about 60,000 psi. In some embodiments, the first material has an elongation at break of about 10% to about 50%. In some embodiments, the first material has an elastic modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the first material has a compressive modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the first material has a shear modulus of about 4,000 ksi to about 10,000 ksi. In some embodiments, the first material has a Poisson's ratio of about 0.25 to about 0.40. In some embodiments, the first material has a strength of about 50 ksi-in 1 / 2 Up to approximately 65 ksi-in 1 / 2 Annealed fracture toughness. In some embodiments, the first material has a resistivity of about 40 μΩ·cm to about 100 μΩ·cm.

[0022] In some embodiments, the method may further include: coating the first material or a portion or all of the first contact surface with a nickel-containing surface coating.

[0023] Overview of the attached figures

[0024] Referring now to the accompanying drawings, which are not necessarily drawn to scale. The accompanying appendices, figures, graphics, images, etc., illustrate various exemplary, non-limiting, inventive aspects, embodiments, and features (“e.g.” or “examples”) according to this disclosure: Figure 1 This is a schematic diagram of a button battery according to one embodiment, immersed in a saliva solution; Figure 2 This is a perspective and cross-sectional view of an electrochemical button cell according to one embodiment; Figure 3 Is it like this? Figure 2 A two-dimensional cross-sectional view of the electrochemical coin cell shown. Figure 4 An example of a curved metal base strip formed therein for a terminal of a button cell according to an embodiment described herein is shown; Figure 5 This is an image of a titanium-clad stainless steel terminal for a button cell battery pack according to the embodiments described herein, showing cracks caused by bending during the manufacturing process of the button cell battery pack. Figure 6 A titanium-based strip for forming terminals of a button cell pack, according to an embodiment described herein, is shown. Figure 7 This is a graph showing the impedance data of the button battery pack of the present invention according to the embodiments described herein; Figure 8 This is a flowchart of a method according to one embodiment described herein; Figure 9 This is a flowchart of a method according to one embodiment described herein; Figure 10 This is a flowchart of a method according to one embodiment described herein; and Figure 11 This is a flowchart of a method according to one embodiment described herein. Invention Details

[0026] Button cell battery packs, also known as coin cells, are small, single-cell battery packs commonly used to power low-power devices such as watches, calculators, hearing aids, and small electronic devices. These battery packs are small and compact, making them easy to use and store, and are available in a variety of sizes, chemistry, and rated voltages.

[0027] Originally developed for hearing aids, button cell batteries are now used in a variety of other applications and devices, such as watches, calculators, and other small electronic devices. A button cell battery typically consists of a positive electrode (cathode), a negative electrode (anode), and an electrolyte that allows ions to flow between the electrodes. The electrodes and electrolyte are encapsulated in a small, round metal casing, usually made of stainless steel or nickel-plated brass.

[0028] The positive electrode is typically made of a metal oxide such as silver oxide or manganese dioxide and coated onto a metal mesh or foil. The negative electrode is typically made of a metal such as zinc or lithium and is also coated onto a metal mesh or foil. The electrolyte is typically a liquid or gel and is designed to allow ions to flow between the electrodes.

[0029] Depending on the battery pack chemistry and rated voltage, the electrodes and electrolyte are arranged in a specific configuration within a metal casing. For example, in a silver oxide-based battery pack, the positive electrode is placed at the center of the pack, while the negative electrode is placed around the outside of the positive electrode. This arrangement allows the battery pack to provide high voltage output while maintaining a small size.

[0030] The external components include a shell or housing defining an internal volume within which the anode and cathode are housed and physically separated by a diaphragm (e.g., an ion-permeable diaphragm, an electrolyte-permeable diaphragm, etc.). The anode and cathode are made of different active materials, such as zinc and manganese dioxide, respectively. These materials are selected based on their electrochemical properties to facilitate the flow of electrons from one terminal to the other. The electrolyte is a liquid or gel substance that allows ions to move between the anode and cathode. Electrolytes are typically a combination of a salt (such as potassium hydroxide) and water.

[0031] Button cell battery packs are available in a variety of chemistry, each with its own unique performance characteristics. For example, alkaline button cell battery packs are the most common type and are typically used in low-power devices such as watches, calculators, and small electronic devices. These packs use an alkaline electrolyte and a zinc-based negative electrode and are available in a variety of sizes and rated voltages. Silver oxide button cell battery packs are commonly used in high-power devices such as cameras, calculators, and medical devices. These packs use a silver oxide positive electrode and a zinc-based negative electrode and are designed to provide high voltage output and long lifespan. Zinc-air button cell battery packs are commonly used in hearing aids and use a zinc-based negative electrode and air as the positive electrode. However, these battery pack chemistry chemistry often has drawbacks such as venting risk, explosion risk, fire risk, shortened battery life, inconsistent discharge, and discharge temperature variation issues. Lithium is a popular alternative to other conventional battery pack chemistry chemistry, especially for low-power devices such as watches, calculators, and small electronic devices that use button cells. These packs typically use a lithium-based positive electrode and a carbon-based negative electrode.

[0032] However, ingestion of button batteries by children can cause serious injury and even death, largely due to the formation of hydroxides (high pH) at the negative terminal or contacts caused by the current from the battery pack. When the negative terminal or contacts of the battery pack come into contact with bodily fluids such as saliva, tissue fluid, mucus, esophageal lining fluid, or gastric juice, the current at the negative terminal or contacts can cause alkalization and / or electrolysis. The hydroxides formed during the alkalization / electrolysis process cause alkali burns and perforations to the oral cavity, esophagus, gastric mucosa, and / or intestines. Severe injury can occur within just two hours of ingestion.

[0033] To address the inherent dangers of the small size of button battery packs, manufacturers have employed anti-swallowing features. One common anti-swallowing feature is a raised border around the button battery pack. This border makes it more difficult for children to swallow the battery pack, but may only help reduce ingestion in infants; toddlers can still swallow button battery packs with a raised border around them. Some button batteries are coated with one or more bittering agents (bitter substances) to deter children from putting them in their mouths. However, not all infants, toddlers, or even older children are prevented from putting button battery packs coated with bittering agents in their mouths. If swallowed, coin batteries or button batteries, whether coated with bittering agents, have a raised border, or are otherwise modified to prevent or deter swallowing, can still cause an electrolytic reaction in a child's mouth, esophagus, stomach, or intestines, and can still cause serious injury or death. Furthermore, even when not swallowed, such as if a child inserts a button battery pack into their nose, ear, or other body cavity, button batteries pose a risk to human health in other situations. For example, when inserted into the nose, button batteries can cause mucosal damage, nasal septum perforation, nasal adhesions, and saddle nose deformity. Therefore, commonly used anti-swallowing technologies, such as bittering coatings, are not effective in preventing children from being dangerously exposed to the alkalization reaction that can occur when children insert button batteries into their nose, ears, or other body cavities.

[0034] This document describes a coin cell battery pack incorporating terminal materials (e.g., positive terminal materials) resistant to such alkali / electrolysis reactions. One option is to use a material resistant to electrolysis reactions for the positive terminal, as electrolysis associated with discharge typically occurs at the positive terminal. Possible positive terminal materials include, but are not limited to, titanium, titanium alloys, titanium nitride, tantalum, niobium, gold, and boron-doped diamond. In some embodiments and for certain applications, titanium, titanium alloys, and / or titanium nitride may be preferred material choices for the positive terminal due to the application's proprietary effectiveness in mitigating electrolysis reactions. In other embodiments, as an alternative to or complement to the positive terminal, the negative terminal and / or the battery pack casing may be made of one or more materials resistant to alkali / electrolysis reactions.

[0035] The inventors discovered that injuries caused by ingested button battery packs occur because the batteries become lodged in the esophagus, where they may be exposed to saliva for extended periods rather than undergoing concentrated corrosive reactions, particularly those believed to occur in the acidic environment of the stomach (as disclosed in the prior art). In cases where saliva is essentially a neutral aqueous solution primarily composed of water, it may be necessary to mitigate the effects of salivary electrolysis that occurs when voltage is generated at the terminals of the lodged battery pack, as will be described in more detail below. The inventors further determined that this phenomenon is particularly severe in children or others with relatively large button battery pack sizes (i.e., those with a total battery outer diameter of approximately 5 mm to approximately 25 mm and a total battery height of approximately 0.5 mm to approximately 10 mm; e.g., CR2016, CR2032, etc.) and / or in children or others with relatively small esophageal diameters.

[0036] The primary electrochemical reaction that occurs after ingesting a coin cell is the electrolysis of water, due to the following factors: (a) the coin cell itself provides a DC voltage, ~3V OCV (open-circuit voltage); (b) an ionicly conductive medium (saliva) connects the anode (+) and cathode (-) terminals; and (c) these two terminals and the saliva conductive path complete the closed loop of the electrolytic cell. An electrochemical reaction will occur if the voltage supply to the electrolytic cell is high enough to overcome polarization and the 1.23V thermodynamic voltage window used for water electrolysis. In fact, the electrolytic reaction associated with ingesting lithium batteries may be more severe than that associated with ingesting alkaline batteries. This is because the driving force (the voltage difference between the battery voltage and the theoretical water electrolysis voltage of 1.23V) is much higher in the case of a 3V lithium battery than in the case of a 1.5V alkaline battery (3.0V - 1.23V = 1.77V in the case of a lithium battery, compared to 1.5V - 1.23V = 0.27V in the case of an alkaline battery).

[0037] It is worth noting that the nomenclature for electrolytic cells is the opposite of that used for battery packs. Therefore, the terms "anode" and "electrolytic anode" refer to the electrode where the oxidation reaction occurs, while the terms "cathode" and "electrolytic cathode" refer to the electrode where the reduction reaction occurs. When assembling an electrolytic cell such as a coin cell and sealing the active electrochemical components within the cell, the negative terminal will be electrically connected to the anode or electrolytic anode, and the positive terminal will be electrically connected to the cathode or electrolytic cathode. It should also be noted that electrolysis requires the application of voltage, thus providing a direct contrast to corrosion that typically occurs naturally under environmental conditions.

[0038] Figure 1To illustrate the electrolytic reaction under discussion, a simulated Li-MnO2 electrochemical button cell 6 is immersed in a saliva solution 5. The main reaction that occurs when a battery with these identical components is accidentally swallowed and becomes lodged in a person's esophagus is shown, although the battery electrodes are shown as discrete components. Specifically, the battery 6 operates at approximately 3V DC and includes a button cell cup (e.g., positive electrode container) 12, a button cell canister (e.g., negative electrode container) 20, an anode 40, and a cathode 50. The anode 40 and cathode 50 contain materials specifically chosen based on their compatibility with the expected electrochemical reaction; for example, xLi + MnO2 → Li^MnO2, where Mn is reduced as lithium ions enter the crystal lattice.

[0039] The outer surface of the button cell cup 12 acts as the negative terminal (cathode in the electrolytic cell), and the outer surface of the button cell canister 20 acts as the positive terminal (anode in the electrolytic cell). Hydrogen evolution occurs on the button cell cup 12 by accepting electrons from the anode 40 of the battery pack, which in this case includes lithium. At the button cell canister 20 (anode in the electrolytic cell), various reactions occur, such as metal dissolution, oxygen evolution, and possible chloride oxidation, and these reactions compete with each other. The salivary solution 5 is kept charge-neutral by the movement of anions 8 from the battery cup 12 (negative terminal) to the button cell canister 20 (positive terminal) and by the opposite movement of cations 7. When metal from the button cell canister 20 oxidizes, it loses electrons to the battery cathode 50, which in this case is manganese dioxide. Ultimately, the final product at the button cell canister 20 depends on its potential, and the solution pH is a result of the combined anodic and cathodic reactions. Furthermore, the solution pH reflects the real-time products generated in the reaction zone between the esophagus and the button cell; therefore, the solution pH is localized and does not necessarily reflect the pH of the overall solution (i.e., the rest of the saliva not close to the reaction zone).

[0040] When a 3V lithium button cell is immersed in a neutral or alkaline saliva solution, the possible electrochemical reactions at button cell cup 12 (negative terminal) are shown below. Note that saliva is usually neutral.

[0041] (1) 2H₂O + 2e - → H2↑ + 2OH - E0 = -0.83V

[0042] (2) O2 + 2H2O + 4e - → 4OH - E0 = -0.4V

[0043] Typically, reaction (1) dominates because oxygen has limited solubility in water, resulting in a very low oxygen concentration in saliva. In either case, hydroxide ions (i.e., OH-)- The production of alkali raises the pH of saliva, potentially to the point of causing alkali burns to the esophagus.

[0044] Saliva can sometimes be acidic. In this case, the reaction at point 12 of the button battery cup is as follows: (1a) 2H + + 2e - → H2↑ E0 = - 0.0V (2a) O2 + 4H + + 4e - → 2H₂O E₀ = 1.23 V In either case, the choice of material used at the negative terminal with a high hydrogen evolution overpotential will shift the dominant reaction 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 localized alkali burns to esophageal tissue.

[0045] When a 3V lithium button cell is immersed in saliva solution 5 and the button cell can 20 contains nickel at least partially along its surface, the possible electrochemical reactions on the button cell can 20 (positive terminal) are as follows.

[0046] (3) 4OH - - 4e - → O2↑ + 2H2O

[0047] (4) Ni - 2e - + 2OH - → Ni(OH)2

[0048] Reaction (4) typically dominates, causing the metallic components in the button cell can 20 to oxidize. In practice, lithium-ion battery cans are typically nickel-plated, as illustrated by the oxidation of nickel in reaction (4). If the button cell can 20 is made of other metals, such as stainless steel, the iron in these alloys could potentially oxidize in a similar reaction. Once the metallic surfaces of the button cell can 20 have been passivated (i.e., by forming a dense oxide film on the bare metal surface), the oxygen evolution reaction (3) may dominate if the voltage is high enough.

[0049] Furthermore, as shown in (3a) and (4a) below, if an iron-based metal (typically some type of steel) is exposed, especially to the extent that hydroxides are present (e.g., through the aforementioned competing reaction) and / or in an acidic environment (e.g., through saliva), dissolution of the metal container 20 is also a possible outcome.

[0050] (3a) Fe - 2e - → Fe 2+(In acidic medium)

[0051] (4a) Fe - 2e - + 2OH - → Fe(OH)2 (in alkaline medium)

[0052] Any combination of the cathodic processes in reactions (1) to (2a) and the anodic processes in reactions (3) to (4a) can be completed. Figure 1 Electrolytic cell 6 is depicted in the diagram. For example, the combination of (1) and (3) results in the following electrolytic reaction in water (i.e., water decomposition): (5) 2H2O → H2↑ + O2↑ Ε0 = - 1.23 V Note that the electrolysis reaction (5) has a thermodynamic potential of 1.23 V, and the negative sign of ΔE0 indicates that the reaction is not spontaneous. Therefore, a DC power supply of at least 1.23 V is required to initiate and sustain reaction (5), and as... Figure 1 As shown, the button cell 6 supplies 3V DC.

[0053] Furthermore, if the amount of sodium chloride (NaCl) in saliva is relatively high, the following electrolysis reaction may occur instead of the reaction (5) discussed earlier: (6) 2NaCl + 2H2O → Cl2↑ + H2↑ + 2NaOH In reaction (6), one of the products is sodium hydroxide (NaOH)—another factor contributing to the high solution pH and potentially alkaline solution that could burn human tissue.

[0054] In short, Figure 1 The conventional electrochemical button cell 6 depicted in the text, and the reactions (1) to (6) associated with its immersion in saliva 5, demonstrate the formation of hydroxide ions by some repetitive electrolysis. Therefore, burns and injuries resulting from an accidentally lodged button cell in the esophagus could be caused by the high salivary pH formed during these reactions, although these reactions and their corresponding effects on pH can be highly localized and difficult to detect (if the pH is not measured near the component involved). In other words, due to the limitations of mass transport in the esophagus, a person with a lodged button cell may experience different pH values ​​in the tissue interacting with the button cell canister 20 (positive end) and the tissue interacting with the button cell cup 12 (negative end), where the solution with a higher pH faces the negative end (i.e., due to the limitations of fluid diffusion within the esophagus). Figure 1 (Button battery cup 12).

[0055] In cases where certain aspects and basic concepts of the various embodiments herein involve saliva and / or saliva-based aqueous solutions, saliva may be represented by the following composition: 0.4 g KCl; 0.4 g NaCl; 0.906 g CaCl2; 0.560 g Na3PO4. - 12H2O; 2 ml 10% H3PO4; 0.0016 g Na2S; 1 g urea; and the remainder deionized water to prepare a 1-liter solution. Although this formulation is intended to mimic human saliva in a standardized manner, minor variations and / or actual human saliva may be used as substitutes, although in such cases, deviations from the representative formulation will be appropriately noted.

[0056] The first aspect of the disclosed method is to mitigate or eliminate destructive electrochemical mechanisms that could lead to injury from accidental ingestion of button batteries through material selection and battery design considerations. For example, the external materials or combinations of materials of the button battery according to this disclosure inhibit or prevent these alkaline electrochemical reactions from occurring. Selecting these material combinations to mitigate or eliminate these electrochemical reactions is a complex task that requires a deep understanding of the main factors influencing the reactions and destructive mechanisms. Furthermore, the selection cannot be arbitrary and must fully consider chemical compatibility, cost, and the convenience of the high-speed and high-volume manufacturing technologies inherent in the battery industry.

[0057] In some embodiments, the electrochemical button cell disclosed in this invention reduces the cathode process in reactions (1) and (2), or (a) and (2a), at [the level of the cathode process]. Figure 1 The possibility of this occurring on the button cell cup 12. Basic testing of the material combinations referenced in these novel batteries confirms this conclusion. For example, button cell positive and negative electrode materials with high overpotentials for the reactions in (1) and (2) and (La) and (2a), and / or increased overpotentials for metal oxidation (M-ne) are used. - → M n+ (where M represents the metal material used on the surface of the positive terminal) reduces or eliminates these electrochemical reactions, keeping all other factors constant, including ~3V DC from the coin cell itself.

[0058] Another approach is to select battery electrode materials that are likely to readily dissolve, undergo oxygen evolution, and generate (at least to some extent) insoluble non-hydroxide reaction products when immersed in saliva at 3 VDC. The formation of these insoluble non-hydroxide reaction products will occur preferentially or exclusively, thereby suppressing the aforementioned undesirable hydroxyl reactions. In this approach, a sufficient quantity of the selected material should be provided to ensure that the substrate material (i.e., the readily electrolytic material) is not exposed for a considerable period of time during which the coin cell can still output a voltage higher than the desired or safe level (typically 2.8 volts or 2.0 volts).

[0059] In another embodiment, the selected material can be coated, coated, or deposited onto the battery, more specifically, onto a surface that may be exposed to saliva in the event of ingestion. This coating must be completely and uniformly formed, as even small cracks, pinholes, or other defects can provide sufficient reaction sites for undesirable reactions along the underlying substrate material. Such a coating would be unsuitable if complete coverage is not achieved or if the coating degrades in situ (i.e., due to anodic bias, reaction with saliva, etc.). While components made of solid gold exhibit the desired properties, a gold coating of approximately 1.4 micrometers (approximately 56 microinches) may be insufficient to provide consistent and repeatable performance.

[0060] As used throughout this specification, whether referring to an anode or cathode container, the term "cladding" or "cladding layer" refers to a continuous, self-contained layer of material with little or no pinholes or other defects. Thus, as a non-limiting example, titanium-clad stainless steel would comprise discrete layers of titanium attached to a stainless steel substrate by any means (e.g., mechanical, chemical, adhesive, welding, etc.). The use of cladding materials like these allows for the selection of a substrate more suitable for a particular manufacturing process. Similarly, as a non-limiting example, the selected cladding material may have the desired overpotential and other properties for electrolytic vessels (as described throughout this specification), while the substrate may exhibit magnetic properties. Clearly, the orientation of the cladding material relative to the substrate will ensure that the exterior of the component / container conforms to the embodiments of this disclosure, while the interior-facing portion of the substrate will be compatible with and non-reactive to the battery active materials and electrolyte.

[0061] It is worth noting that the use of covering materials may result in exposed edges, for example... Figure 2 and 3 The terminal edge 23 shown, including the cross-section of both the overlay and the substrate, may be exposed in an undesirable manner. In this case, a sealant can be applied to prevent any unwanted reaction. For example, a polymer sealant, more preferably a UV-curable sealant, can be applied around the edge and gasket area to cover the exposed edge.

[0062] Figure 2 and Figure 3 An arrangement of an electrochemical button cell 10 well suited to the aspects and embodiments of this disclosure is depicted, although the electrochemical button cell 10 may employ various alternative component orientations and arrangements. Furthermore, the specific apparatuses and processes shown in the drawings and described herein are exemplary embodiments of the inventive concept defined in the appended claims. Therefore, precise dimensions and physical properties associated with the embodiments disclosed herein should not be considered limiting unless such dimensions or properties are inherent to producing the desired reaction.

[0063] The electrochemical button cell 10 includes an anode terminal 12 (i.e., a battery cap or cup), which includes a closed end 13, an open end 14 having a terminal edge 15, and a sidewall 16 extending between the closed end 13 and the open end 14. Figure 2 and 3 In the battery pack nomenclature, the anode terminal 12 serves as the negative electrode of the electrochemical button cell 10. Furthermore, the anode terminal 12 is composed of a conductive material that is resistant to the electrochemical reaction of hydrogen formation upon exposure to a solution containing saliva (e.g., saliva solution 5). For example, the anode terminal 12 can be made of a copper-tin-zinc alloy (e.g., about 40% to about 65% by weight of Cu, about 30% to about 45% by weight of Sn, and / or about 4% to about 15% by weight of Zn), nickel metal, stainless steel, and / or another electronic conductor having a high hydrogen evolution overpotential. Additionally, the material selected for the anode terminal 12 can have an onset potential for hydrogen evolution in saliva in the approximate range of -0.66V to -1.96V relative to a standard hydrogen electrode (SHE). Preferably, the material selected for the anode terminal 12 exhibits an onset potential for hydrogen evolution in saliva that is significantly lower than -0.66V and closer to -1.96V relative to the SHE.

[0064] like Figure 2 and 3 As shown, the electrochemical button cell 10 also includes a cathode terminal 20 (i.e., a battery canister), which includes a closed end 21, an open end 22 having a terminal edge 23, and a sidewall 24 extending between the closed end 21 and the open end 22. The cathode terminal 20 serves as the positive electrode of the button cell. Furthermore, the cathode terminal 20 is composed of a conductive material that is resistant to metal dissolution and the electrochemical reaction of oxygen formation upon exposure to a solution containing saliva. Specifically, the cathode terminal 20 may be formed of titanium, titanium alloys, titanium nitride, tantalum, niobium, gold, boron-doped diamond, or another electronic conductor that resists metal dissolution under anodic bias and preferably has a high oxygen evolution overpotential. The closed end 21 may also be provided with a composition comprising titanium metal, titanium alloys, titanium nitride, tantalum, niobium, gold, boron-doped diamond, or another electronic conductor that resists metal dissolution under anodic bias and preferably has a high oxygen evolution overpotential. Furthermore, the material for the cathode terminal 20 may be selected having an onset potential for the anodic reaction in saliva in a general range of +0.6V to +2.4V relative to the SHE. Preferably, the material for the cathode terminal 20 is selected to exhibit an onset potential for the anodic reaction in saliva that is significantly higher than +0.6V and closer to +2.4V relative to the SHE.

[0065] While local pH levels are believed to be a cause of damage from ingested batteries, experimental results have demonstrated that measuring pH alone may be insufficient to determine the efficacy of any proposed solutions. The inventors have determined that pH variations are sensitive to experimental conditions, including the exposed surface area of ​​the positive and negative terminals, the amount of saliva present, and the means and location of the pH measurement device. Therefore, any pH measurement results are most useful only when compared. Currently, the inventors are unaware of any published and standardized clinical testing protocols for simulating or quantifying the effects of button battery ingestion on humans.

[0066] Another method for evaluating the level of undesirable electrolytic activity between terminals when a "live" battery is placed in saliva is to quantify the amount of metal dissolved in the saliva solution. As an example, elemental analysis by inductively coupled plasma (ICP) mass spectrometry can be used to determine the presence of metals. In the same manner, such quantitative measurements can also be used to determine the effectiveness of coatings or cladding materials.

[0067] The electrochemical button cell 10 may further include a sealing gasket 30 provided between the anode terminal 12 and the cathode terminal 20. Figure 2 and 3 Gasket 30 is typically made of a non-conductive elastomeric material capable of providing a compression seal between anode terminal 12 and cathode terminal 20. The material used for gasket 30 can be selected with reference to its stability in the presence of an electrolyte, its resilience, and its resistance to cold flow. Suitable materials for gasket 30 include: nylon, polytetrafluoroethylene, fluorinated ethylene-propylene, trichlorofluoroethylene, perfluoroalkoxy polymers, polyethylene, polyethylene, polypropylene, polystyrene, polysulfone, etc.

[0068] The electrochemical button cell 10 also includes an electrolyte 34. As will be understood by those skilled in the art, various materials can be used for the electrolyte 34. For example, the electrolyte 34 may consist of a composition of at least one lithium salt dissolved in an organic solvent or a blend of organic solvents. Suitable salts for lithium button cells are lithium trifluoromethanesulfonate, lithium trifluoromethanesulfonylimide, lithium perchlorate, lithium tetrafluoroborate, lithium hexafluorophosphate, or combinations thereof. Common organic solvents for lithium button cells are propylene carbonate and 1,2-dimethoxyethane.

[0069] The electrochemical button cell 10 also has an anode 40 electrically connected to the anode terminal 12. As will be understood by those skilled in the art, the anode 40 can be composed of various alkali metals and their alloys with aluminum or magnesium, provided that the composition is suitable for serving as the anode in the electrochemical cell. In one embodiment, the anode 40 is primarily composed of lithium material, which is suitable as the anode in an electrochemical cell having a cathode primarily composed of manganese dioxide.

[0070] The electrochemical button cell 10 also includes a cathode 50 arranged in electrical connection with the cathode terminal 20. As will be understood by those skilled in the art, the cathode 50 can be composed of various materials suitable for use as a cathode in a lithium-based electrochemical cell. In one embodiment, the cathode 50 is primarily composed of manganese dioxide.

[0071] The electrochemical button cell 10 may further include a separator 38 disposed between the anode 40 and the cathode 50 to provide insulation between them. The separator 38 may be composed of any of a variety of polymeric materials, such as those providing electrical insulation between the anode terminal 12 and the cathode terminal 20. For example, the separator 38 may be formed of a polypropylene or polyethylene nonwoven film with a thickness between about 20 μm and about 60 μm.

[0072] Similarly, Figure 2 and 3 As shown, the electrochemical button cell 10 can be configured as a coin cell, a button cell, or any other suitable configuration. In some embodiments, the electrochemical button cell may have dimensions at least partially defined by the total cell outer diameter 54 and the total cell height 58. The total cell outer diameter 54 may be between about 5 mm and about 25 mm, and the total cell height 58 may be between about 0.5 mm and about 10 mm. It is generally understood that button cells or coin cells with these dimensions are most likely to become lodged in the esophagus after accidental ingestion. For example, the electrochemical button cell 10 may be manufactured in a configuration such as CR2016 as defined by the International Electrotechnical Commission (TEC), wherein the total cell outer diameter 54 has a diameter of about 20 mm and the total cell height 58 has a thickness of about 1.6 mm.

[0073] Another embodiment relates to an electrolysis-resistant lithium primary battery having an initial open-circuit voltage exceeding 2.0 volts, more preferably exceeding 2.8 volts. Alternatively, the lithium primary battery has a nominal voltage of approximately 3.0 volts and / or approximately 2.8 volts. The surface of the externally exposed components of the battery will comprise a material having the desired hydrogen overpotential and / or other properties associated with the electrolytic reaction (more specifically, electrolysis that is undesirable upon exposure to saliva as described above). All additional features, components, and properties described in the preceding paragraphs apply to this embodiment.

[0074] Another embodiment relates to an electrochemical cell having an open-circuit voltage of more than 2.0 volts, more preferably more than 2.8 volts. Alternatively, a lithium primary cell has a nominal voltage of approximately 3.0 volts and / or approximately 2.8 volts. The exposed exterior of the cell, more specifically the outer surfaces of the negative electrode container and the positive electrode container, comprises a material that does not precipitate hydroxides and / or otherwise cause electrolysis of aqueous solutions. For example, the material used for, for example, the exterior of the negative electrode container may have the desired hydrogen overpotential and / or other properties associated with the electrolytic reaction (more specifically, electrolysis that is undesirable upon exposure to saliva), all as described above. All the additional features, components, and properties described above are applicable to this embodiment.

[0075] Another aspect of the disclosed method relates to a method of constructing and / or manufacturing an electrolysis-resistant button cell. The method includes providing a lithium-containing negative electrode active material, placing said material in two separate halves of a conductive container, and providing a non-aqueous organic liquid electrolyte before hermetically sealing the two halves of the conductive container to form the cell. The composition of the two halves of the conductive container is selected to have a desired hydrogen overpotential and / or other properties related to the electrolytic reaction (more specifically, electrolysis undesirable upon exposure to saliva), all as described above.

[0076] Another aspect of the disclosed method is to provide and / or manufacture electrolysis-resistant battery packs to avoid injuries associated with ingestion of said batteries, and methods for avoiding injuries caused by battery ingestion. In these aspects, any of the aforementioned battery designs and constructions can be provided. At the heart of the method of the invention is the manufacture of electrolysis-resistant battery packs and the provision of said battery packs for sale and / or use by consumers.

[0077] As used throughout this specification, any reference to a particular grade should be assumed to be to a standard published by ASTM International, unless the context indicates some other reference known to a person skilled in the art of metallurgy. In light of the foregoing and all the information contained in the examples below, consider an electrochemical button cell having any combination of the following characteristics: Anode, more preferably an anode electrically connected to the anode terminal; The anode comprises a material selected from lithium and lithium alloys; Cathode, more preferably a cathode electrically connected to a cathode terminal; The cathode contains manganese dioxide; The electrolyte, more preferably an electrolyte comprising a non-aqueous material capable of promoting an electrochemical reaction that generates an open-circuit voltage of at least about 2.8 volts or a nominal voltage of about 3.0 volts; A gasket, more preferably, is disposed between the anode terminal and the cathode terminal and provides a seal between the anode terminal and the cathode terminal; A diaphragm is disposed between the anode and the cathode, and more preferably, electrical insulation is also provided between the anode and the cathode; The total outer diameter of the battery is approximately 5 mm to approximately 25 mm, and the total outer height of the battery is approximately 0.5 mm to approximately 10 mm. An anode terminal includes a closed end, an open end having a terminal edge, and a sidewall extending between the closed end and the open end of the anode terminal, wherein the closed end of the anode terminal: (a) is configured as an electronic conductor and contains a material resistant to the reaction of hydrogen formation during exposure to a solution containing saliva and / or (b) is substantially composed of an electronic conductor resistant to the reaction of hydrogen formation during exposure to a solution containing saliva; A cathode terminal comprising a closed end, an open end having a terminal edge, and a sidewall extending between the closed end and the open end of the cathode terminal, wherein the closed end of the cathode terminal: (a) is configured as an electronic conductor and comprises a material resistant to metal dissolution and oxygen formation reactions during exposure to the saliva-containing solution and / or (b) is substantially composed of an electronic conductor resistant to metal dissolution and oxygen formation reactions during exposure to the saliva-containing solution; The closed end of the anode terminal comprises or is substantially composed of a material that has a significant hydrogen evolution overpotential during exposure to a solution containing saliva, and more preferably, the material having a significant hydrogen evolution overpotential during exposure to a solution containing saliva exhibits an onset potential for hydrogen evolution in a solution containing saliva in the range of approximately -0.66V to approximately -1.96V relative to a standard hydrogen electrode. The closed end of the anode terminal comprises or is substantially composed of a material that conducts electrons and is resistant to the reaction of hydrogen formation during exposure to a solution containing saliva, and more preferably, the material having a significant hydrogen evolution overpotential during exposure to a solution containing saliva exhibits an onset potential for hydrogen evolution in a solution containing saliva in the range of approximately -0.66V to approximately -1.96V relative to a standard hydrogen electrode. The closed end of the cathode terminal comprises or is substantially composed of a material that is resistant to metal dissolution and has a significant oxygen evolution overpotential during exposure to a solution containing saliva, and more preferably, the material that is resistant to metal dissolution and has a significant oxygen evolution overpotential during exposure to a solution containing saliva exhibits an onset potential for the anodic reaction in a solution containing saliva in the range of approximately +0.6V to approximately +2.4V relative to a standard hydrogen electrode. The closed end of the cathode terminal comprises or is substantially composed of a material that conducts electrons and is resistant to the reaction that causes metal dissolution and oxygen formation during exposure to a solution containing saliva, and more preferably, the material that is resistant to metal dissolution and has a significant oxygen evolution overpotential during exposure to a solution containing saliva exhibits an onset potential for the anodic reaction in a solution containing saliva in the range of approximately +0.6V to +2.4V relative to a standard hydrogen electrode. The closed end of the anode terminal is substantially composed of nickel metal, stainless steel, or a copper-tin-zinc alloy containing 30 to 45% by weight of tin and 4 to 15% by weight of zinc alloying elements. The closed end of the cathode terminal is substantially composed of a material selected from titanium, titanium alloys, titanium nitride, tantalum, niobium, gold, and boron-doped diamond.

[0078] Furthermore, in view of the foregoing and the information contained in the examples below, consider any combination of electrochemical button cells having the following characteristics: The internal components, including the anode, diaphragm, and cathode, are capable of generating an output open-circuit voltage of approximately 2.8 volts in the presence of a non-aqueous electrolyte. A flat cylindrical container encapsulating the internal components, having an outer diameter of approximately 5 mm to approximately 25 mm and an outer height of approximately 0.5 mm to approximately 10 mm, the container comprising an anode terminal housing and a cathode terminal housing, wherein an electrically insulating gasket is disposed between the anode terminal housing and the cathode terminal housing; The anode terminal housing has an inner surface that maintains electrical contact with the anode and an outer surface containing a material resistant to the reaction that forms hydrogen gas during exposure to a solution containing saliva; The cathode terminal housing has an inner surface that maintains electrical contact with the cathode and an outer surface containing a material resistant to metal dissolution and oxygen formation reactions during exposure to a solution containing saliva. The anode comprises an active material consisting essentially of lithium or a lithium-based alloy, and the cathode comprises an active material containing manganese dioxide. The outer surface of the anode terminal housing exhibits an onset potential for hydrogen evolution in a solution containing saliva, in the range of approximately -0.66V to -1.96V relative to a standard hydrogen electrode. The outer surface of the anode terminal housing is selected from: nickel metal, stainless steel, and copper-tin-zinc alloy containing about 30% to about 45% tin and about 4% to about 15% zinc alloying elements by weight; The outer surface of the cathode material housing exhibits an onset potential for the anodic reaction in a solution containing saliva in the range of approximately +0.6V to +2.4V relative to a standard hydrogen electrode; and / or The outer surface of the cathode terminal housing is selected from: titanium metal, titanium alloy, titanium nitride, tantalum, niobium, stainless steel, gold, and boron-doped diamond.

[0079] Furthermore, in view of the foregoing and the information contained in the embodiments below, a method for manufacturing a button-shaped battery pack having an outer diameter of 5-25 mm and an outer height of approximately 0.5 mm to approximately 10 mm, being resistant to electrolysis when placed in an aqueous solution initially having a neutral pH, the button-shaped battery pack having any combination of the following characteristics: An anode material containing lithium or a lithium alloy is placed inside a container having an anode terminal, wherein the entire outer surface of the anode terminal is made of a material that is resistant to the reaction that forms hydrogen when the final, manufactured battery is immersed. The cathode material is placed inside a container with cathode terminals, wherein the entire outer surface of the cathode terminals is made of a material that is resistant to metal dissolution and oxygen formation reactions when the final, manufactured battery is immersed. The diaphragm and insulating gasket are positioned between the anode and cathode and the container is sealed to produce the final, manufactured battery; The outer surface of the anode terminal is selected to represent the initial potential for hydrogen evolution when the final, fabricated cell is immersed, relative to a standard hydrogen electrode in the range of approximately -0.66V to -1.96V. The outer surface of the cathode terminal is selected to represent the onset potential of the anodic reaction when the final, fabricated battery is immersed, relative to a standard hydrogen electrode in the range of approximately +0.6V to +2.4V; and / or The outer surface of the cathode terminal is selected from: titanium metal, titanium alloy, titanium nitride, tantalum, niobium, stainless steel, gold, and boron-doped diamond.

[0080] Finally, in view of the foregoing and the information contained in the examples below, consider a button cell battery pack having an outer diameter of about 5 mm to about 25 mm and an outer height of about 0.5 mm to about 10 mm that is resistant to electrolysis when placed in an aqueous solution with an initial pH of about 7.0 or lower, and the button cell battery pack having any combination of the following characteristics: The exposed surface of the anode terminal is essentially composed of: nickel metal, stainless steel, copper-tin-zinc alloy or a combination thereof containing approximately 30% to 45% wt% tin and approximately 4% to 15% zinc alloying elements by weight. The exposed surface of the cathode terminal is essentially composed of: titanium metal, titanium alloy, titanium nitride, tantalum, niobium, gold, and boron-doped diamond, or combinations thereof; and It further includes an anode active material containing lithium and a cathode active material containing manganese dioxide.

[0081] The following examples further illustrate the nature, uses, and advantages of various embodiments of this disclosure, comparing electrolytic test results of conventional electrochemical batteries with those of novel batteries constructed by the inventors. These novel batteries are examples of this disclosure and reflect the inventors' findings on the electrochemical mechanism of damage caused by accidental ingestion of a button battery that becomes lodged in the esophagus.

[0082] Button battery packs, such as those described above (e.g., electrochemical button battery 10), are typically manufactured by forming the positive electrode portion of a button battery casing or housing from sheets or strips of metallic material. The positive electrode portion of the button battery casing or housing includes a positive terminal or contact. The positive electrode portion of the button battery casing or housing may include sidewalls. The positive electrode portion of the button battery casing or housing can be formed by pressing or stamping sheets or strips of metallic material above or within a mold, below a mold, between two molds, etc. The positive terminal or positive electrode can be formed simultaneously with the sidewalls from sheets or strips of the same metallic material as the sidewalls, or the positive terminal or positive electrode can be formed separately from the sidewalls and subsequently joined to the sidewalls to form the positive electrode portion of the button battery casing or housing.

[0083] The negative electrode portion of a button cell housing or casing for a button cell battery pack (e.g., an electrochemical button cell 10) may have a similar morphological specification to that of the positive electrode portion of the button cell housing or casing. Alternatively, the negative electrode portion of the button cell housing or casing may have a morphological specification formed differently from that used to form the positive electrode portion of the button cell housing or casing. For example, the positive electrode portion of the button cell housing or casing may have a flat or substantially flat portion containing contacts, such as positive contacts or terminals. Like the positive electrode portion, the negative electrode portion of the button cell housing or casing may include sidewalls. The negative electrode portion of the button cell housing or casing may be formed by pressing or stamping a sheet or strip of metal material above or within a mold, below a mold, between two molds, etc. The negative terminal or negative electrode can may be formed simultaneously with the sidewalls from a sheet or strip of the same metal material as the sidewalls, or the negative terminal or negative electrode can may be formed separately from the sidewalls and subsequently joined to the sidewalls to form the negative electrode portion of the button cell housing or casing.

[0084] Alternatively, the positive or negative portion of the button cell housing or casing for a button cell pack (e.g., electrochemical button cell 10) may include a flat portion containing positive or negative contacts or terminals.

[0085] The positive electrode portion of a button cell housing or canister may, for example, form the internal volume of the positive electrode canister for a button cell. Similarly, the negative electrode portion of a button cell housing or canister may form the internal volume of the negative electrode portion when including negative contacts or terminals and sidewalls. The dimensions and configuration of the internal volume of the negative electrode portion and / or the internal volume of the positive electrode portion of the button cell housing or canister may allow for the inclusion, retention, housing, or otherwise placement of at least a portion of one or more internal components of the button cell assembly. Internal components may include a cathode, anode, separator, one or more current collectors, electrolyte, and / or other components, members, or materials. Internal components may include, but are not limited to, features, members, and materials that contribute to the electrochemical function of the button cell assembly.

[0086] A button cell battery pack (e.g., an electrochemical button cell 10) can be formed by incorporating all or part of the internal components into the inner volume of the negative and / or positive electrode portions of a button cell housing or casing, and by attaching the positive electrode portion of the button cell housing or casing to the negative electrode portion in order to substantially seal the internal components of the button cell battery pack within the inner volume of the button cell housing or casing, the inner volume of which is defined at least by the inner volumes of the negative and positive electrode cans of the button cell housing or casing.

[0087] To join the negative and positive portions of a button cell housing or casing together, a portion of one or both sidewalls of the positive / negative portions of the button cell housing or casing may be curled, bent, folded, coiled, wrapped, or otherwise partially physically entangled or inserted. For example, the top edges of the sidewalls of the negative and / or positive portions of the housing or casing may be bent or folded together to form a seal.

[0088] Now for reference Figure 4 A bent sheet of material to form the negative or positive electrode portion of a button battery casing or outer shell can be bent at an angle A. 弯曲 Additionally or alternatively, the sheet of bent material to form the negative or positive terminal of a coin cell assembly (e.g., electrochemical coin cell 10) can be bent at an angle A. 弯曲 The bending angle A is determined based on the specific shape and specifications of the negative or positive electrode portion of the button cell and / or based on the specific method of joining the negative and positive electrode portions of the button cell casing or housing. 弯曲 It can be an acute or obtuse angle. In some cases, such as when forming a button cell assembly (e.g., an electrochemical button cell 10) with rounded corners (e.g., 20 or 21) between the sidewall and the terminal (e.g., 17 or 25), the bending angle A is... 弯曲 It can be less than approximately 90°. As used herein, the term "bending angle" (e.g., bending angle A) is used in conjunction with other terms. 弯曲 ( ) can refer to the internal radial space around the intersection point between two intersecting lines. In some embodiments, the bending angle A 弯曲 Less than approximately 180°, less than approximately 135°, less than approximately 90°, less than approximately 80°, less than approximately 70°, less than approximately 60°, less than approximately 50°, less than approximately 40°, or less than approximately 30°, including all values ​​and ranges therein.

[0089] The A 弯曲 It can form a bending degree D 弯曲 It is defined as the exterior angle formed between the original plane of the bent portion of the sheet or strip and the final bent portion of the sheet or strip. In some embodiments, the degree of bending D... 弯曲 It can be greater than approximately 20°, greater than approximately 40°, greater than approximately 60°, greater than approximately 80°, greater than approximately 90°, or greater than approximately 100°, including all values ​​and ranges in between.

[0090] Additionally or alternatively, a bending angle A can be formed by joining the negative and positive portions of the button battery casing or housing together, for example, by curling, bending, folding, winding, wrapping, or otherwise partially physically entangled or inserted together. 弯曲 .

[0091] When the bending angle A 弯曲 This refers to the stress that, when materials are bent, rolled, joined, or otherwise physically shaped into portions of a coin cell assembly (e.g., an electrochemical coin cell 10), can cause material strain in a desired and / or undesirable manner when the internal angle is small. For example, stress applied to sheets or strips containing metallic materials to achieve a bending angle A... 弯曲 The bending force can lead to the successful and desired bending of a sheet or strip containing metallic materials. Conversely, the bending force applied to the sheet or strip containing metallic materials to achieve a bending angle A... 弯曲 Bending forces can cause sheets or strips containing metallic materials to thin at the apex of the bend. In some cases, bending forces are applied to the sheets or strips containing metallic materials to achieve a bending angle A. 弯曲 The bending force can cause a portion of the bent material to be sheared within the bend apex or along the indentation from the bend apex.

[0092] Figure 5 A double-clad material strip comprising an iron-containing material covered within a titanium-containing material is shown. The reason for using such a double-clad material strip comprising an iron-containing material covered within a titanium-containing material is particularly that the titanium-containing material is better resistant to alkalization reactions, such as those described elsewhere herein, while the iron-containing material may be more prone to inducing such alkalization reactions when the coin cell battery pack is swallowed or otherwise comes into contact with bodily fluids. Therefore, by coating the iron-containing material with the titanium-containing material, the aim is to reduce or eliminate such alkalization reactions in the event of the coin cell battery pack being swallowed or otherwise coming into contact with bodily fluids. However, when forming and / or joining the positive electrode portion of the casing or housing of a coin cell battery pack (e.g., an electrochemical coin cell 10), such as when stamping the positive electrode portion or bending a portion of the sidewall of the positive electrode portion to seal the positive electrode portion to seal the coin cell battery pack, small radii and large bends may be required. Such bending and / or curling of the material, such as when forming or joining the positive electrode portion of the casing or housing, can lead to the formation of cracks or tears, such as... Figure 5 The image shows a vertically oriented tear. When such a tear occurs during the manufacturing process of a coin cell assembly due to bending or curling / joining of the material used in the positive electrode portion of the coin cell assembly (e.g., electrochemical coin cell 10), the titanium-containing material covering the iron-containing material may no longer prevent the iron-containing material from being exposed to bodily fluids. This could mean that if such a coin cell is swallowed or otherwise comes into contact with bodily fluids, an undesirable alkalization reaction may still occur.

[0093] When button cell battery packs containing these contacts / terminals are exposed to saliva, etc., many other materials besides titanium are considered suitable for forming button cell battery pack components (e.g., cathode terminal 20), such as certain grades of titanium and titanium alloys, based on their resistance to electrolytic reactions and hydroxide formation. However, each of these materials is considered suitable for covering another material, typically an iron-containing material, which would otherwise be used to form button cell battery pack contacts or terminals. When used as a cover or coating for iron-containing terminal / contact materials, each of these materials will produce cracks during the molding process of the positive electrode portion of the housing or casing and / or during the joining of the positive / negative electrode portions of the housing or casing of the button cell battery pack (e.g., electrochemical button cell 10). For example, foils and strips made of industrially pure (CP) Grade 2 titanium (which is the most common type of titanium) have been found to exhibit several cracks during the molding process of the positive electrode portion of the housing or casing used for button cell battery packs. Severe cracking was also observed at one or more corners of the positive electrode portion of the casing when using double-clad foil, strip, or sheet containing stainless steel and ASTM Grade 2 titanium, such as Figure 5 As shown in the image. Therefore, materials that are intolerant to such alkalization, electrolysis, and / or hydroxide formation reactions (such as stainless steel or other iron-containing materials) are subsequently exposed to saliva, tissue fluid, or other bodily fluids, resulting in undesirable electrolysis and high pH at the negative contacts or terminals of the button cell battery pack.

[0094] The application of Ti or TiN coatings to stainless steel substrates also leads to cracks, pinholes, or scratches on the surface of the coating during the molding process of the positive / negative electrode portion of the casing or housing of the coin cell assembly (e.g., electrochemical coin cell 10). Therefore, the stainless steel substrate is not completely covered by Ti or TiN, causing electrolytic reactions and high pH at the terminals (e.g., anode terminal 12) when the coin cell assembly comes into contact with bodily fluids.

[0095] Surprisingly, certain materials and combinations of materials have been found to provide solutions for the manufacture of components (e.g., cathode terminal 20) of button cell packs (e.g., electrochemical button cell 10), which are resistant to alkalization / electrolysis reactions and experience less or no cracking or other destructive material strain during the molding of the terminals (or cathode terminal 20) and / or other components of the casing or housing (e.g., closed end 21, sidewall 24, outer surface 25 of closed end 21) and / or assembly of the button cell pack.

[0096] To resolve these and / or other issues, refer to at least the following: Figure 8-11The invention describes a button cell assembly (e.g., an electrochemical button cell 10), materials for forming at least a portion of the button cell assembly (e.g., an electrochemical button cell 10) (e.g., a cathode terminal 20), and related methods (e.g., 70, 80, 90, 100).

[0097] Now refer to Figure 6 The diagram illustrates a titanium-based strip 60. In some embodiments, the positive electrode portion of a coin cell battery pack may be formed from the titanium-based strip 60. The positive electrode portion may include, form, serve as, or otherwise serve as a terminal (e.g., cathode terminal 20). The titanium-based strip 60 may have any suitable dimensions, such as a length sufficient to form one or more positive electrode portions for one or more coin cell battery packs (e.g., electrochemical coin cell 10).

[0098] In some embodiments, the thickness of the titanium-based strip 60 can be less than about 5 mm, less than about 2 mm, less than about 1.5 mm, less than about 1 mm, or less than about 0.5 mm, less than about 0.4 mm, less than about 0.3 mm, less than about 0.2 mm, or less than about 0.1 mm, including all values ​​and ranges therein. In some embodiments, the thickness of the titanium-based strip 60 is about 1.5 mm. In another embodiment, the thickness of the titanium-based strip 60 is about 0.2 mm. In yet another embodiment, the titanium-based strip 60 is about 0.3 mm. For example, if the titanium-based strip 60 is to be used in a CR2032 battery with a total height of about 2.9 mm to about 3.2 mm, the thickness of the titanium-based strip 60 can be from about 1 mm to about 1.8 mm. In other instances, if the titanium-based strip 60 is to be used for ECR1216, CR1216, CR1220, BR1225, CR1616, CR1620, CR1632, CR2016, CR2025, CR2430 and / or other such coin cells, such as any 3V cell, the thickness of the titanium-based strip 60 may vary based on the required total height of the coin cell itself, such as based on a total height ratio of approximately 5:1 to approximately 3:1 for the thickness of the titanium-based strip 60.

[0099] In some embodiments, the composition of the titanium-based strip 60 can be adjusted to achieve specific mechanical properties above or below a certain threshold or within a certain range. For example, when the composition of the titanium-based strip 60 is adjusted based on a specific weight percent composition of other constituent components (such as iron, oxygen, carbon, nitrogen, hydrogen, etc.), the composition of the titanium-based strip 60 can provide a titanium-based sheet 60 with the desired mechanical properties that are not readily apparent in terms of related durability and crack prevention before experimentation with different material compositions.

[0100] In some embodiments, the titanium-based strip 60 may be bent when forming a housing or casing for a coin cell battery pack or joining the positive / negative electrode portions of a housing or casing for a coin cell battery pack, wherein the bending radius of the bend is approximately 50% to approximately 500% (e.g., approximately 100% to approximately 200%) of the thickness of the titanium-based strip 60. In some embodiments, when the titanium-based strip 60 is bent, for example according to ASTM Test Method E290, a bending radius of approximately 50% to approximately 500% (e.g., approximately 100% to approximately 200%) of the thickness of the titanium-based strip 60 may be applied before any or substantially any cracks or microcracks are formed in the titanium-based strip 60. For example, in one embodiment where the titanium-based strip 60 is to be used in a CR2032 battery—where the thickness of the titanium-based strip 60 is 0.2 mm—the bending radius of the bend may be approximately 0.1 mm to approximately 0.4 mm. In another embodiment where the titanium-based strip 60 is to be used in a CR2032 battery, the thickness of the titanium-based strip 60 is 0.3 mm, and the bending radius of the bend can be from about 0.15 mm to about 0.6 mm.

[0101] In some embodiments, the composition of the titanium-based strip 60 can be adjusted to achieve specific values ​​or ranges of specific mechanical properties of the titanium-based strip 60, such as one or more of the following: ultimate tensile strength, elastic modulus, elongation at break, compressive modulus, shear modulus, Poisson's ratio, annealed fracture toughness, elongation or percentage elongation, resistivity and / or similar parameters.

[0102] For example, the composition of the titanium-based strip 60 can be adjusted to achieve an ultimate tensile strength greater than about 30,000 psi, greater than about 40,000 psi, greater than about 50,000 psi, greater than about 60,000 psi, or greater than about 70,000 psi, including all values ​​and ranges therein and in between.

[0103] For example, the composition of the titanium-based strip 60 can be adjusted to achieve an elongation at break of approximately 10% to approximately 50%, approximately 10% to approximately 40%, or approximately 20% to approximately 40%, including all values ​​and ranges therein and in between. Without wishing to be bound by any particular theory, percentage elongation (also known as “% elongation”) can be important for eliminating or reducing crack formation during the molding process of cans (e.g., positive electrode cans) for button cell packs at room temperature (e.g., approximately 21°C).

[0104] For example, the composition of the titanium-based strip 60 can be adjusted to achieve an elastic modulus greater than about 5,000 ksi, greater than about 10,000 ksi, greater than about 12,000 ksi, greater than about 14,000 ksi, greater than about 16,000 ksi, greater than about 18,000 ksi, greater than about 20,000 ksi, greater than about 25,000 ksi, greater than about 30,000 ksi, or greater than about 35,000 ksi, including all values ​​and ranges therein and in between.

[0105] For example, the composition of the titanium-based strip 60 can be adjusted to achieve a compressive modulus greater than about 10,000 ksi, greater than about 12,000 ksi, greater than about 14,000 ksi, greater than about 16,000 ksi, greater than about 18,000 ksi, greater than about 20,000 ksi, greater than about 25,000 ksi, greater than about 30,000 ksi, or greater than about 35,000 ksi, including all values ​​and ranges therein and in between.

[0106] For example, the composition of the titanium-based strip 60 can be adjusted to achieve a shear modulus greater than about 1,000 ksi, greater than about 5,000 ksi, greater than about 10,000 ksi, greater than about 15,000 ksi, greater than about 20,000 ksi, greater than about 25,000 ksi, or greater than about 30,000 ksi, including all values ​​and ranges therein and in between.

[0107] For example, the composition of the titanium-based strip 60 can be adjusted to achieve a Poisson's ratio of about 0.10 to about 0.70, about 0.20 to about 0.60, about 0.30 to about 0.50, about 0.30 to about 0.40, about 0.20 to about 0.70, about 0.30 to about 0.60, or about 0.25 to about 0.40, including all values ​​and ranges therein.

[0108] For example, the composition of the titanium-based strip 60 can be adjusted to achieve a value greater than approximately 30 ksi-in. 1 / 2 Greater than approximately 40 ksi-in 1 / 2 Greater than approximately 50 ksi-in 1 / 2 Greater than approximately 60 ksi-in 1 / 2 Greater than approximately 70 ksi-in 1 / 2 Greater than approximately 80 ksi-in 1 / 2 Greater than approximately 90 ksi-in 1 / 2 or greater than approximately 100 ksi-in 1 / 2Annealed fracture toughness, including all values ​​and ranges therein and in between.

[0109] For example, the composition of the titanium-based strip 60 can be adjusted to achieve an elongation at room temperature (e.g., about 21°C) greater than about 20% (e.g., from about 20% to about 50%), including all values ​​and ranges therein and in between.

[0110] For example, the composition of the titanium-based strip 60 can be adjusted to achieve approximately 10 µΩ. cm, less than approximately 20 µΩ cm, less than approximately 50 µΩ cm, less than approximately 100 µΩ cm, or less than approximately 200 µΩ The resistivity in cm, including all values ​​and ranges therein and in between.

[0111] Table 1 below provides several exemplary titanium-based strips (e.g., 60) and their corresponding mechanical properties, where UTS refers to ultimate tensile strength, YS to yield strength, EM to modulus of elasticity, SM to shear modulus, PR to Poisson's ratio, E to elongation (at room temperature, e.g., approximately 21°C), B to the minimum bending radius relative to the thickness (T) of the titanium-based strip (e.g., 60) (e.g., 1.8 mm thickness) for bending tests according to American Society for Testing and Materials (ASTM) bending test procedure E290, R to resistivity, Gr. to exemplary ASTM grade values ​​for industrially pure (CP) or alloy materials, and Cl. to Japanese Industrial Standards Committee (JISC) grade values ​​for CP or alloy materials. Table 1

[0112] ASTM B265-11 describes ASTM Test Method E290 in more detail, the entire contents of which are incorporated herein by reference for all purposes. The bending test of the exemplary material described herein is performed according to ASTM Test Method E290 using Method 1, Guided Bend Test as described in paragraph 3.6, by bending the material at 105° and allowing the bent material to spring back naturally, as described in Section 6.3 of ASTM B265-11.

[0113] In some embodiments, the titanium-based strip 60 can be bent to form the outer peripheral portion of a planar conductive portion (e.g., terminals or contacts) of a button cell housing or casing. In some embodiments, the outer peripheral portion formed by the titanium-based strip 60 can be formed by bending a portion of the titanium-based strip 60 out of plane of the remaining portion of the planar conductive portion by approximately 90 degrees to approximately 270 degrees, such as when engaging with a sidewall of the housing or when forming terminals or contacts from the titanium-based strip 60.

[0114] In some embodiments, a surface coating or layer may be applied to the surface of the titanium-based strip 60 or formed as the outer surface of the titanium-based strip 60. For example, the surface coating or outer surface of the titanium-based strip 60 may contain one or more of the following substances: TiN, Ti2N, or TiC. Without wishing to be bound by any particular theory, the surface coating as described herein can reduce the contact resistance between the positive electrode can surface formed by the coated titanium-based strip 60 and the device contacts in which the button cell battery pack is used.

[0115] In some embodiments, when bent, the titanium-based strip 60 may have a non-fracture bending radius relative to the thickness of the titanium-based strip that is less than about 500%, less than about 200%, less than about 175%, less than about 150%, or less than about 125%, including all values ​​and ranges therein and in between. For example, a titanium-based strip 60 having a thickness of 0.2 mm and a bending radius of 0.3 mm has a bending radius of 150% relative to the thickness of the titanium-based strip 60.

[0116] In some embodiments, once the titanium-based strip 60 is bent, no or substantially no cracks or microcracks occur at or near the bend.

[0117] In some embodiments, the titanium-based strip 60 may contain one or more of the following substances in measurable amounts: nitrogen, carbon, hydrogen, iron, oxygen, aluminum, vanadium, tin, ruthenium, palladium, cobalt, molybdenum, chromium, nickel, niobium, zirconium, silicon, or titanium. Exemplary compositions for the titanium-based strip 60 are provided herein, wherein all percentage (%) values ​​are provided as “weight percentage”, “wt.%”, “wt%”, or “wt%”, including cases where only “%” is used.

[0118] The titanium-based strip 60 can be formed into part of a housing or outer casing, such as terminals or other conductive parts, sidewalls, and / or internal components of a button battery pack. In some embodiments, the titanium-based strip 60 may contain more than about 95% by weight of titanium, more than about 96% by weight of titanium, more than about 97% by weight of titanium, more than about 98% by weight of titanium, more than about 99% by weight of titanium, or more than about 99.5% by weight of titanium, including all values ​​and ranges therein.

[0119] In some embodiments, the titanium-based strip 60 may contain less than about 0.50% by weight of iron, less than about 0.25% by weight of iron, or less than about 0.10% by weight of iron, including all values ​​and ranges therein.

[0120] In some embodiments, the titanium-based strip 60 may contain less than about 0.50% by weight of oxygen, less than about 0.25% by weight of oxygen, or less than about 0.10% by weight of oxygen, including all values ​​and ranges therein.

[0121] In some embodiments, the titanium-based strip 60 may contain less than about 0.25% by weight of carbon, less than about 0.10% by weight of carbon, or less than or equal to about 0.08% by weight of carbon, including all values ​​and ranges therein.

[0122] In some embodiments, the titanium-based strip 60 may contain less than about 0.10% by weight of nitrogen, less than about 0.08% by weight of nitrogen, less than about 0.06% by weight of nitrogen, or less than about 0.04% by weight of nitrogen, including all values ​​and ranges therein.

[0123] In some embodiments, the titanium-based strip 60 may contain less than about 0.10% by weight of hydrogen, less than about 0.05% by weight of hydrogen, less than about 0.04% by weight of hydrogen, less than about 0.03% by weight of hydrogen, or less than about 0.02% by weight of hydrogen, including all values ​​and ranges therein.

[0124] In some embodiments, the titanium-based strip 60 may comprise or consist substantially of: less than or equal to about 0.100% carbon, less than or equal to about 0.015% hydrogen, less than or equal to about 0.300% iron, less than or equal to about 0.030% nitrogen, less than or equal to about 0.25% oxygen, greater than or equal to about 99.00% titanium, less than or equal to about 0.400% molybdenum, less than or equal to about 0.25% palladium, less than or equal to about 0.50% niobium, less than or equal to about 0.05% aluminum, less than or equal to about 0.060% ruthenium, and less than or equal to about 0.060% nickel.

[0125] In some embodiments, the titanium-based strip 60 may comprise or consist substantially of: less than or equal to about 0.100% carbon, less than or equal to about 0.015% hydrogen, less than or equal to about 0.400% iron, less than or equal to about 0.030% nitrogen, less than or equal to about 0.17% oxygen, greater than or equal to about 81% titanium, less than or equal to about 16% molybdenum, less than or equal to about 3.2% niobium, less than or equal to about 3.5% aluminum, and less than or equal to about 0.40% residues.

[0126] In some embodiments, the titanium-based strip 60 may comprise or consist substantially of: about 0.080% to 0.100% carbon, about 0.013% to 0.015% hydrogen, about 0.200% to 0.300% iron, less than or equal to about 0.030% nitrogen, about 0.100% to 0.25% oxygen, greater than or equal to about 99.00% titanium, 0% to about 0.400% molybdenum, 0% to about 0.25% palladium, 0% to about 0.060% ruthenium, and 0% to about 0.060% nickel.

[0127] In some embodiments, the titanium-based strip 60 may comprise or consist substantially of: less than or equal to about 0.10% carbon, less than or equal to about 0.015% hydrogen, less than or equal to about 0.20% iron, less than or equal to about 0.030% nitrogen, less than or equal to about 0.18% oxygen, and greater than or equal to about 99.175% titanium, with the balance including other trace elements or contaminants. Titanium-based strip 60 having such a composition will possess some or all of the desired physical, mechanical, electrical, and electrochemical properties described herein, such as relatively high durability, relatively high ductility, relatively low resistivity, and a relatively near-zero electrolytic potential. Titanium-based strip 60 having such a composition can be formed as terminals or contacts (e.g., positive terminal cups) for button cell packs (e.g., electrochemical button cell 10), which may have negative terminal cups formed of different materials.

[0128] In some embodiments, the titanium-based strip 60 may comprise or consist substantially of: less than or equal to about 0.08% carbon, less than or equal to about 0.015% hydrogen, less than or equal to about 0.20% iron, less than or equal to about 0.030% nitrogen, less than or equal to about 0.18% oxygen, less than or equal to about 0.25% palladium, with the balance being titanium. A titanium-based strip 60 having such a composition will possess some or all of the desired physical, mechanical, electrical, and electrochemical properties described herein, such as relatively high durability, relatively high ductility, relatively low resistivity, and a relatively near-zero electrolytic potential. A titanium-based strip 60 having such a composition can be formed as a terminal or contact (e.g., a positive terminal canister) for a coin cell assembly (e.g., an electrochemical coin cell 10), which may have a negative terminal canister formed of a different material.

[0129] In some embodiments, the titanium-based strip 60 may comprise or consist substantially of: less than or equal to about 0.080% carbon, less than or equal to about 0.015% hydrogen, less than or equal to about 0.30% iron, about 0.20% to about 0.40% molybdenum, about 0.60% to about 0.90% nickel, less than or equal to about 0.030% nitrogen, less than or equal to about 0.25% oxygen, about 97.725% to about 99.20% titanium, with the balance including other trace elements or contaminants. A titanium-based strip 60 having such a composition will possess some or all of the desired physical, mechanical, electrical, and electrochemical properties described herein, such as relatively high durability, relatively high ductility, relatively low resistivity, and a relatively near-zero electrolytic potential. Titanium-based strip 60 having such a composition can be formed into terminals or contacts (e.g., positive terminal canisters) for button cell packs (e.g., electrochemical button cell 10), which may have negative terminal canisters formed of different materials.

[0130] In some embodiments, the titanium-based strip 60 may comprise or consist substantially of: less than or equal to about 0.080% carbon, less than or equal to about 0.015% hydrogen, less than or equal to about 0.20% iron, less than or equal to about 0.030% nitrogen, less than or equal to about 0.18% oxygen, and greater than or equal to about 99.175% titanium, with the balance including other trace elements or contaminants. Titanium-based strip 60 having such a composition will possess some or all of the desired physical, mechanical, electrical, and electrochemical properties described herein, such as relatively high durability, relatively high ductility, relatively low resistivity, and a relatively near-zero electrolytic potential. Titanium-based strip 60 having such a composition can be formed as terminals or contacts (e.g., positive terminal cups) for button cell packs (e.g., electrochemical button cell 10), which may have negative terminal cups formed of different materials.

[0131] In some embodiments, the titanium-based strip 60 may comprise or consist substantially of: less than or equal to about 0.10% carbon, less than or equal to about 0.015% hydrogen, less than or equal to about 0.20% iron, less than or equal to about 0.030% nitrogen, less than or equal to about 0.18% oxygen, and about 99.00% to about 99.92% titanium, with the balance including other trace elements or contaminants. Titanium-based strip 60 having such a composition will possess some or all of the desired physical, mechanical, electrical, and electrochemical properties described herein, such as relatively high durability, relatively high ductility, relatively low resistivity, and a relatively near-zero electrolytic potential. Titanium-based strip 60 having such a composition can be formed as terminals or contacts (e.g., positive terminal cups) for button cell packs (e.g., electrochemical button cell 10), which may have negative terminal cups formed of different materials.

[0132] In some embodiments, the titanium-based strip 60 may comprise or consist substantially of: less than or equal to about 0.080% carbon, less than or equal to about 0.013% hydrogen, less than or equal to about 0.20% iron, less than or equal to about 0.030% nitrogen, less than or equal to about 0.15% oxygen, with the balance comprising or substantially consisting of titanium. A titanium-based strip 60 having such a composition will possess some or all of the desired physical, mechanical, electrical, and electrochemical properties described herein, such as relatively high durability, relatively high ductility, relatively low resistivity, and a relatively near-zero electrolytic potential. A titanium-based strip 60 having such a composition can be formed as a terminal or contact (e.g., a positive terminal canister) for a coin cell assembly (e.g., an electrochemical coin cell 10), which may have a negative terminal canister formed of a different material.

[0133] In some embodiments, the titanium-based strip 60 may comprise or consist substantially of: less than or equal to about 0.080% carbon, less than or equal to about 0.013% hydrogen, less than or equal to about 0.20% iron, less than or equal to about 0.030% nitrogen, less than or equal to about 0.18% oxygen, about 0.12% to about 0.25% palladium, with the balance comprising or substantially consisting of titanium. A titanium-based strip 60 having such a composition will possess some or all of the desired physical, mechanical, electrical, and electrochemical properties described herein, such as relatively high durability, relatively high ductility, relatively low resistivity, and a relatively near-zero electrolytic potential. A titanium-based strip 60 having such a composition can be formed as a terminal or contact (e.g., a positive terminal canister) for a coin cell assembly (e.g., an electrochemical coin cell 10), which may have a negative terminal canister formed of a different material.

[0134] In some embodiments, the titanium-based strip 60 may comprise or consist substantially of: less than or equal to about 0.080% carbon, less than or equal to about 0.015% hydrogen, less than or equal to about 0.20% iron, less than or equal to about 0.030% nitrogen, less than or equal to about 0.10% oxygen, about 0.04% to about 0.06% ruthenium, about 0.04% to about 0.06% nickel, with the balance comprising or substantially consisting of titanium. Titanium-based strips having such a composition (e.g., titanium-based strip 60) will possess some or all of the desired physical, mechanical, electrical, and electrochemical properties described herein, such as relatively high durability, relatively high ductility, relatively low resistivity, and a relatively near-zero electrolytic potential. Titanium-based strips (e.g., titanium-based strip 60) having such a composition can be formed into terminals or contacts (e.g., positive terminal canisters) for button cell packs (e.g., electrochemical button cell 10), which may have negative terminal canisters formed of different materials.

[0135] Table 2 below provides several exemplary titanium-based strips (e.g., titanium-based strip 60) that correspond to the titanium-based strips with the mechanical properties listed in Table 1. Table 2 also provides the composition of each of these titanium-based strips (e.g., titanium-based strip 60).

[0136] Table 2

[0137] The following describes several non-limiting examples of titanium-containing or titanium-based can materials used for molding the positive electrode can of button batteries. Table 3 provides an overview of several of the numerous examples, including a comparison of construction and compositional differences relative to comparative examples at a high level.

[0138] Table 3

[0139] Example 1

[0140] A titanium-based strip (e.g., titanium-based strip 60) with a thickness of approximately 0.2 mm to approximately 0.3 mm is formed. The titanium-based strip is composed of approximately 0.10% carbon, approximately 0.015% hydrogen, approximately 0.20% iron, approximately 0.030% nitrogen, approximately 0.18% oxygen, and approximately 99.175% titanium, with the balance including other trace elements or contaminants that do not materially affect the mechanical properties (e.g., cold formability) of the titanium-based strip. The titanium-based strip (e.g., titanium-based strip 60) is tested (e.g., according to ASTM B265-20a) and its elongation at break is determined to be approximately 27% of the length of the titanium-based strip. Using Method 1, according to, for example, ASTM E290, a bend with a radius of curvature approximately 1.5 times the thickness of the titanium-based strip is formed in the titanium-based strip using mechanical stress at approximately room temperature (e.g., approximately 21°C). Once bent, the titanium-based strip (e.g., titanium-based strip 60) does not develop any or substantially no cracks or microcracks at or near the bend, inside or outside the bend apex, or along the bend indentation.

[0141] Example 2

[0142] A titanium-based strip (e.g., titanium-based strip 60) with a thickness of approximately 0.2 mm to approximately 0.3 mm is formed. The titanium-based strip is composed of approximately 0.10% carbon, approximately 0.015% hydrogen, approximately 0.20% iron, approximately 0.030% nitrogen, approximately 0.18% oxygen, and approximately 99.175% titanium, with the balance including other trace elements or contaminants that do not materially affect the mechanical properties (e.g., cold formability) of the titanium-based strip. The titanium-based strip (e.g., titanium-based strip 60) is at least partially covered or coated with a material comprising one or more of the following substances: TiN, Ti2N, or TiC on the surface of the titanium-based strip, the surface being selected based on a specific bending procedure, such that the configuration and size of the bent titanium-based strip can otherwise face the outside of the terminals or contacts of the coin cell battery pack, thereby further reducing or eliminating, for example, the contact resistance between the positive terminal or contact of the coin cell battery pack and the corresponding contact of a device in which the coin cell battery pack is configured to be disposed or otherwise electrically connected.

[0143] Impedance spectra of the button cell were recorded by electrochemical impedance spectroscopy (EIS) using a Solartron frequency response analyzer (FRA), model SI 1250, controlled by a Solartron potentiostat, model SI 1286 (Solartron Metrology, West Sussex, UK). A small voltage amplitude of 10 mV was applied to the voltage leads, and the response current was measured (4-point probe configuration). Frequency sweeps started at 65,000 Hz and decreased to 1 Hz, with data collected using Zplot, version 2.4. Internal resistance was determined by fitting the impedance semicircle to the intercept of the impedance spectrum at high frequencies to the real spectrum, such as... Figure 7 As shown.

[0144] As described above, the resistivity of titanium-based strips (e.g., titanium-based strip 60) used for positive electrode can construction was measured using a four-point collinear probe. Table 4 compares the resistivity of titanium-based strips (e.g., titanium-based strip 60) used for conventional coin cell construction with that of conventional stainless steel-based strips.

[0145] Table 4

[0146] As shown above, titanium-based tapes (e.g., titanium-based tape 60) have a lower resistivity than SS430-based tapes. Therefore, titanium-based tapes are more suitable as positive electrode / terminal / contact materials because they do not cause electrical problems related to discharge, and still provide a reduced or eliminated incidence of alkalization / electrolysis reactions in the final coin cell assembly when in contact with bodily fluids such as saliva.

[0147] Furthermore, while titanium is generally prone to oxidation, titanium-based strips (e.g., titanium-based strip 60), especially when coated as described herein, reduce or prevent oxidation and associated corrosion of the titanium-based terminals / can housings compared to conventional CR2023 button cell packs. However, under normal use and storage, the formed TiO₂... x (Where x = 1 to 2) The oxide layer is very thin. This thin layer has the benefit of preventing further corrosion of the Ti material. Therefore, in these applications, titanium is more corrosion-resistant than nickel or stainless steel. Moreover, thin TiO₂... x The layer does not affect or substantially does not affect the battery resistance, as shown in Table 5 below.

[0148] Table 5

[0149] Unwilling to be bound by any particular theory, due to the electron tunneling effect, a thin layer of TiO2 is formed on the outer surface of the can / terminal. xThe layers may not affect or substantially affect the battery resistance, as shown in Table 5.

[0150] Example 3

[0151] A titanium-based strip (e.g., titanium-based strip 60) with a thickness of about 0.2 mm to about 0.3 mm is formed. The titanium-based strip is composed of about 0.080% carbon, about 0.013% hydrogen, about 0.30% iron, about 0.030% nitrogen, about 0.25% oxygen, about 0.20% to about 0.40% molybdenum, about 0.60% to about 0.90% nickel, and about 97.725% to about 99.20% titanium, with the balance including other trace elements or contaminants that do not substantially affect the mechanical properties (e.g., cold formability) of the titanium-based strip.

[0152] One or more surfaces of a titanium-based strip (e.g., titanium-based strip 60) are at least partially covered or coated with a material comprising or composed of nickel. In some preferred embodiments, a very thin nickel layer is formed on both surfaces of the titanium-based strip. The nickel layer on the titanium-based strip may face outwards toward the terminals or contacts (e.g., the positive terminal) of the coin cell, thereby further reducing or eliminating contact resistance between the terminals, such as the positive terminal, or contacts of the coin cell pack and the corresponding contacts of a device in which the coin cell pack is configured to be disposed or otherwise electrically connected. This nickel layer can reduce the resistance between the positive can / contact and the corresponding contacts of the device using the coin cell pack. When the titanium-based strip is at least partially plated or coated with a thin nickel layer on both sides, it has been found that they reduce the resistance between the positive can / terminal and the corresponding contacts of the device using the coin cell pack, and further found that the resistance between the positive can / terminal and the cathode inside the coin cell pack is reduced.

[0153] Typically, titanium-based strips (e.g., titanium-based strip 60) are annealed during the production process. This is because titanium readily oxidizes in air, forming TiO₂. x Oxides (x=1 to 2), especially when x=2, typically exhibit very high conductivity in oxidized titanium-based strips, and contact resistance can be high if the TiO2 layer is too thick. Therefore, it has been found that applying a nickel-based coating comprising one or more of the following to one or both surfaces of the titanium-based strip during the annealing process provides less oxidation and a thinner TiO2 layer. xAn oxide layer, which reduces the contact resistance of the completed / formed positive electrode can / terminal: TiN, Ti2N, and / or TiC. The TiN, Ti2N, and / or TiC layers formed on the surface of the titanium-based strip can reduce contact resistance due to the low resistivity of these materials. In some embodiments, this nickel-based coating can be applied by annealing the titanium-based strip (e.g., cold-rolled titanium sheet) in a nitrogen atmosphere for forming TiN and Ti2N on the surface of the titanium-based strip or an argon atmosphere for forming TiC on the surface of the titanium-based strip. The formed TiN and Ti2N or TiC structure can be continuous or discontinuous on the surface of the titanium-based strip / sheet.

[0154] In terms of thickness, a thin nickel substrate (e.g., <1 μm, preferably <0.5 μm) can be used. The nickel substrate can be applied, plated, or otherwise disposed on the titanium-based strip / sheet / foil (e.g., titanium-based strip 60) by any suitable means or method. For example, the titanium-based strip can be cleaned, and a nickel-based coating can be applied or otherwise plated onto the surface of the titanium-based strip using conceivable methods such as electrolytic processes or electroless deposition plating techniques. The nickel-based coating / plating is disposed on one or both sides of the titanium surface of the titanium-based strip / sheet / foil.

[0155] Now for reference Figure 8 The diagram illustrates a method 70 that can be implemented by any suitable means. Method 70 may include: forming at 71 a sheet comprising more than about 97% by weight titanium. Method 70 may further include: at 72, shaping the sheet into a terminal of an electrochemical coin cell. Method 70 may optionally further include: at 73, sealing the active electrochemical components within the internal volume of the electrochemical coin cell by engaging the circumferential edge of the terminal to one or more portions of a cylindrical housing cup such that the contacts are electrically connected to the active electrochemical components of the coin cell assembly.

[0156] In some embodiments, the active electrochemical components within the internal volume of the electrochemical coin cell may include an anode, a separator, and a cathode. In some embodiments, the active electrochemical components are configured to generate an output open-circuit voltage of at least 2.8 volts in the presence of a non-aqueous electrolyte.

[0157] In some embodiments, the size and configuration of the terminals (e.g., formed from titanium-based sheet 60) make them resistant to reactions that produce hydroxides upon exposure to bodily fluids.

[0158] In some embodiments, the strip (e.g., titanium-based strip 60) contains less than about 0.5 wt% iron, less than about 0.5 wt% oxygen, less than about 0.5 wt% carbon, less than about 0.5 wt% nitrogen, and less than about 0.5 wt% hydrogen. In some embodiments, the sheet contains less than about 0.3 wt% iron, less than about 0.25 wt% oxygen, less than about 0.1 wt% carbon, less than about 0.03 wt% nitrogen, and less than about 0.015 wt% hydrogen.

[0159] In some embodiments, the strip (e.g., titanium-based strip 60) has an ultimate tensile strength of about 40,000 psi to about 60,000 psi. In some embodiments, the strip (e.g., titanium-based strip 60) has an elongation at break of about 10% to about 50%. In some embodiments, the strip (e.g., titanium-based strip 60) has an elastic modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the strip (e.g., titanium-based strip 60) has a compressive modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the strip (e.g., titanium-based strip 60) has a shear modulus of about 4,000 ksi to about 10,000 ksi. In some embodiments, the strip (e.g., titanium-based strip 60) has a Poisson's ratio of about 0.25 to about 0.40. In some embodiments, the strip (e.g., titanium-based strip 60) has approximately 50 ksi-in 1 / 2 Up to approximately 65 ksi-in 1 / 2 Annealed fracture toughness. In some embodiments, the strip (e.g., titanium-based strip 60) has approximately 40 µΩ. cm to approximately 100 µΩ The resistivity is 1 cm.

[0160] In some embodiments, the strip (e.g., titanium-based strip 60) has an ultimate tensile strength of about 40,000 psi to about 60,000 psi, an elongation at break of about 10% to about 50%, an elastic modulus of about 10,000 ksi to about 20,000 ksi, a compressive modulus of about 10,000 ksi to about 20,000 ksi, a shear modulus of about 4,000 ksi to about 10,000 ksi, a Poisson's ratio of about 0.25 to about 0.40, and a strength of about 50 ksi-in. 1 / 2 Up to approximately 65 ksi-in 1 / 2 Annealed fracture toughness, and approximately 40 µΩ cm to approximately 100 µΩ The resistivity is 1 cm.

[0161] In some embodiments, the method may further include annealing the strip (e.g., titanium-based strip 60) prior to terminal forming. In some embodiments, the method may further include coating part or all of the sheet with a nickel-containing surface coating.

[0162] Now for reference Figure 9 The diagram illustrates a method 80 that can be implemented by any suitable means. Method 80 may include: at 81, forming a first contact surface with a first sheet composed of a first material comprising more than about 95% by weight titanium. Method 80 may further include: at 82, forming a cylindrical housing cup with a second sheet composed of a second material different from the first material, the cylindrical housing cup comprising a substantially flat bottom and sidewalls circumferentially formed around the substantially flat bottom, the substantially flat bottom forming a second contact surface of the electrochemical button cell, the substantially flat bottom and sidewalls forming an inner volume. In some embodiments, the second material comprises stainless steel. Method 80 may further include: at 83, disposing an active electrochemical component within the inner volume of the cylindrical housing cup, the active electrochemical component comprising an anode, a separator, and a cathode, wherein the active electrochemical component is configured to generate an output open-circuit voltage of at least 2.8 volts in the presence of a non-aqueous electrolyte. Method 80 may further include: at 84, engaging the circumferential edge of the first contact surface to one or more portions of the sidewall of the cylindrical housing cup, such that the first and second contact surfaces are electrically connected to the active electrochemical component.

[0163] In some embodiments, the active electrochemical components within the internal volume of the electrochemical coin cell may include an anode, a separator, and a cathode. In some embodiments, the active electrochemical components are configured to generate an output open-circuit voltage of at least 2.8 volts in the presence of a non-aqueous electrolyte.

[0164] In some implementations, the size and configuration of the first contact surface can make it resistant to the reaction that produces hydroxides during exposure to bodily fluids.

[0165] In some embodiments, the first material comprises less than about 0.5 wt% iron, less than about 0.5 wt% oxygen, less than about 0.5 wt% carbon, less than about 0.5 wt% nitrogen, and less than about 0.5 wt% hydrogen, with the balance or substantially all of the composition being titanium. In some embodiments, the first material comprises less than about 0.3 wt% iron, less than about 0.25 wt% oxygen, less than about 0.1 wt% carbon, less than about 0.03 wt% nitrogen, and less than about 0.015 wt% hydrogen, with the balance or substantially all of the composition being titanium.

[0166] In some embodiments, the first material has an ultimate tensile strength of about 40,000 psi to about 60,000 psi. In some embodiments, the first material has an elongation at break of about 10% to about 50%. In some embodiments, the first material has an elastic modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the first material has a compressive modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the first material has a shear modulus of about 4,000 ksi to about 10,000 ksi. In some embodiments, the first material has a Poisson's ratio of about 0.25 to about 0.40. In some embodiments, the first material has a strength of about 50 ksi-in 1 / 2 Up to approximately 65 ksi-in 1 / 2 Annealed fracture toughness. In some embodiments, the first material has approximately 40 µΩ. cm to approximately 100 µΩ The resistivity is 1 cm.

[0167] In some embodiments, the method may further include coating a portion or all of the first material with a nickel-containing surface coating. In some embodiments, coating at least a portion of the first material is performed by annealing a sheet of the first material. In some embodiments, the sheet of the first material may be annealed in an argon-rich or nitrogen-rich atmosphere. In some embodiments, the annealing of the sheet of the first material may be performed before the first sheet of the first material is used to form the contacts, terminals, or other portions of a button cell.

[0168] As shown in Table 1, the resistance to alkalization reactions (e.g., those mentioned above) Figure 1 Various intended compositions of sheets (e.g., titanium-based strip 60) composed of materials (e.g., the first material) used in the electrolytic formation reaction can have all or some of these mechanical, physical, and electrical properties.

[0169] Now for reference Figure 10The diagram illustrates a method 90 that can be implemented by any suitable means. Method 90 may include: at 91, providing a material comprising more than about 99% by weight of titanium, less than about 0.10% of carbon, less than about 0.015% of hydrogen, less than about 0.20% of iron, less than about 0.030% of nitrogen, and less than about 0.18% of oxygen. Method 90 may further include: at 92, rolling the material into a sheet at room temperature (e.g., about 21°C). Method 90 may further include: at 93, coating at least a portion of the sheet with a surface coating comprising one or more of the following: nickel, TiN, Ti₂N, or TiC. Method 90 may further include: at 94, forming one or more bends in the sheet to form terminals for an electrochemical button cell.

[0170] In some embodiments, at least a portion of the coated sheet is annealed. In some embodiments, the sheet may be annealed in an argon-rich or nitrogen-rich atmosphere.

[0171] In some embodiments, the method may further include forming a housing or casing of an electrochemical coin cell, the housing or casing having an internal volume configured to house an active electrochemical component. The active electrochemical component may include an anode, a separator, and a cathode. In some embodiments, the active electrochemical component is configured to generate an output open-circuit voltage of at least 2.8 volts in the presence of a non-aqueous electrolyte. To form the electrochemical coin cell, terminals may be sealed to one or more sidewalls of the housing or casing.

[0172] In some embodiments, the size and configuration of the materials and / or terminals make them resistant to reactions that produce hydroxides upon exposure to bodily fluids.

[0173] In some embodiments, the material comprises less than about 0.5 wt% iron, less than about 0.5 wt% oxygen, less than about 0.5 wt% carbon, less than about 0.5 wt% nitrogen, and less than about 0.5 wt% hydrogen. In some embodiments, the material comprises less than about 0.3 wt% iron, less than about 0.25 wt% oxygen, less than about 0.1 wt% carbon, less than about 0.03 wt% nitrogen, and less than about 0.015 wt% hydrogen.

[0174] In some embodiments, the material has an ultimate tensile strength of about 40,000 psi to about 60,000 psi. In some embodiments, the material has an elongation at break of about 10% to about 50%. In some embodiments, the material has an elastic modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the material has a compressive modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the material has a shear modulus of about 4,000 ksi to about 10,000 ksi. In some embodiments, the material has a Poisson's ratio of about 0.25 to about 0.40. In some embodiments, the material has a strength of about 50 ksi-in. 1 / 2 Up to approximately 65 ksi-in 1 / 2 Annealed fracture toughness. In some embodiments, the material has approximately 10 µΩ. cm to approximately 100 µΩ The resistivity is 1 cm.

[0175] Now for reference Figure 11 The diagram illustrates a method 100 that can be implemented by any suitable means. Method 100 may include: at 101, forming a first contact surface of an electrochemical coin cell from a first sheet of a first material comprising more than approximately 99% by weight titanium. Method 100 may further include: at 102, forming a cylindrical housing cup from a second sheet of a second material, the cylindrical housing cup including a substantially flat bottom and sidewalls circumferentially formed around the substantially flat bottom, the substantially flat bottom forming a second contact surface of the electrochemical coin cell, the substantially flat bottom and sidewalls forming an inner volume. Method 100 may further include: at 103, disposing an active electrochemical component within the inner volume of the cylindrical housing cup, the active electrochemical component including an anode, a separator, and a cathode, wherein the active electrochemical component is configured to generate an output open-circuit voltage of at least 2.8 volts in the presence of a non-aqueous electrolyte. Method 100 may further include: at 104, engaging the circumferential edge of the first contact surface to one or more portions of the sidewall of the cylindrical housing cup such that the first and second contact surfaces are electrically connected to the active electrochemical component, thereby sealing the active electrochemical component within the internal volume of the electrochemical coin cell.

[0176] In some embodiments, the circumferential edge of the first contact surface is engaged to one or more portions of the sidewall of the cylindrical housing cup by bending or curling the circumferential edge of the first contact surface or one or more portions of the sidewall of the cylindrical housing cup.

[0177] In some implementations, the size and configuration of the first contact surface make it resistant to the reaction that produces hydroxides during exposure to human bodily fluids.

[0178] In some embodiments, the first material comprises less than about 0.5 wt% iron, less than about 0.5 wt% oxygen, less than about 0.5 wt% carbon, less than about 0.5 wt% nitrogen, and less than about 0.5 wt% hydrogen, with the balance or substantially all of the composition being titanium. In some embodiments, the first material comprises less than about 0.3 wt% iron, less than about 0.25 wt% oxygen, less than about 0.1 wt% carbon, less than about 0.03 wt% nitrogen, and less than about 0.015 wt% hydrogen, with the balance or substantially all of the composition being titanium.

[0179] In some embodiments, the first material has an ultimate tensile strength of about 40,000 psi to about 60,000 psi. In some embodiments, the first material has an elongation at break of about 10% to about 50%. In some embodiments, the first material has an elastic modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the first material has a compressive modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the first material has a shear modulus of about 4,000 ksi to about 10,000 ksi. In some embodiments, the first material has a Poisson's ratio of about 0.25 to about 0.40. In some embodiments, the first material has a strength of about 50 ksi-in 1 / 2 Up to approximately 65 ksi-in 1 / 2 Annealed fracture toughness. In some embodiments, the first material has approximately 40 µΩ. cm to approximately 100 µΩ The resistivity is 1 cm.

[0180] In some embodiments, method 100 may optionally further include coating at least a portion of a first sheet composed of a first material with a nickel-containing surface coating at location 105. In some embodiments, coating at least a portion of the first sheet composed of the first material can be performed by annealing the first sheet of the first material. In some embodiments, the first sheet can be annealed in an argon-rich or nitrogen-rich atmosphere. In some embodiments, the annealing of the first sheet of the first material can be performed before the first contact is formed from the first sheet composed of the first material.

[0181] Various embodiments relate to button cell battery packs, and more particularly to button cell battery packs comprising titanium-based contact materials having improved cold formability for safer button cell battery packs.

[0182] According to one embodiment, a housing is provided configured for an electrochemical coin cell, the housing comprising: a casing having a flat wall and sidewalls, the sidewalls extending from one or more edges of the flat wall of the casing to form a casing can; and a planar conductive portion engaged with the sidewall of the casing to form an inner cavity configured to accommodate an active component of the electrochemical coin cell, wherein the casing or the planar conductive portion comprises more than about 95% by weight of titanium, and wherein the radius of curvature between the flat wall and the sidewall of the casing is about 100% to about 200% of the thickness of one or more of the casing or the planar conductive portion.

[0183] In some embodiments, the housing or the planar conductive portion comprises more than about 99 wt% titanium. In some embodiments, the housing or the planar conductive portion comprises less than about 0.5 wt% iron, less than about 0.5 wt% oxygen, less than about 0.5 wt% carbon, less than about 0.5 wt% nitrogen, and less than about 0.5 wt% hydrogen. In some embodiments, the housing or the planar conductive portion comprises about 0.3 wt% iron, about 0.25 wt% oxygen, about 0.1 wt% carbon, about 0.03 wt% nitrogen, and about 0.015 wt% hydrogen. In some embodiments, the housing or the planar conductive portion has an ultimate tensile strength of about 40,000 psi to about 60,000 psi. In some embodiments, the housing or the planar conductive portion has an elongation at break of about 10% to about 50%. In some embodiments, the housing or the planar conductive portion has an elastic modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the housing or the planar conductive portion has a compressive modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the housing or the planar conductive portion has a shear modulus of about 4,000 ksi to about 10,000 ksi. In some embodiments, the housing or the planar conductive portion has a Poisson's ratio of about 0.25 to about 0.40. In some embodiments, the housing or the planar conductive portion has a compressive modulus of about 50 ksi-in. 1 / 2 Up to approximately 65 ksi-in 1 / 2 Annealed fracture toughness. In some embodiments, the housing or the planar conductive portion has an elongation greater than about 20% (e.g., about 20% to about 50%) at room temperature (e.g., about 21°C). In some embodiments, the housing or the planar conductive portion has about 40 µΩ. cm to approximately 100 µΩ The resistivity is 1 cm.

[0184] In some embodiments, when engaged with the sidewall of the housing, the outer peripheral portion of the planar conductive portion bends outward from the plane of the remaining portion of the planar conductive portion by approximately 90 degrees to approximately 160 degrees. In some embodiments, one or more of the housing or the planar conductive portion includes a surface portion comprising one or more of the following: TiN, Ti₂N, or TiC. In some embodiments, one or more of the housing or the planar conductive portion includes a surface coating comprising nickel. In some embodiments, the housing or the planar conductive portion comprises a material resistant to reactions that lead to the formation of hydroxides.

[0185] According to another embodiment, an electrochemical button cell can be provided, comprising: a cylindrical casing including a positive electrode contact surface and sidewalls circumferentially formed around the positive electrode contact surface, wherein the cylindrical casing defines an inner volume; an anode material disposed within a first portion of the inner volume; a cathode material disposed within a second portion of the inner volume; a separator disposed within the inner volume between the anode material and the cathode material; an electrolyte material disposed within the inner volume and configured to transport ions between the anode material and the cathode material; and a planar negative electrode contact surface disposed within or adjacent to the inner volume such that the anode material, cathode material, separator, and electrolyte material are encapsulated within the inner volume, wherein a portion of the sidewalls engages with an edge of the planar negative electrode contact surface to seal the inner volume of the cylindrical casing. In some embodiments, the thickness of the planar negative electrode contact surface is from about 0.1 mm to about 0.5 mm. In some embodiments, the radius of curvature at the edge of the planar negative electrode contact surface relative to the sidewalls of the cylindrical casing is from about 1 mm to about 5 mm.

[0186] In some embodiments, the titanium-containing material comprises more than about 95% by weight of titanium. In some embodiments, the titanium-containing material comprises more than about 99% by weight of titanium. In some embodiments, the titanium-containing material comprises less than about 0.5% by weight of iron, less than about 0.5% by weight of oxygen, less than about 0.5% by weight of carbon, less than about 0.5% by weight of nitrogen, and less than about 0.5% by weight of hydrogen. In some embodiments, the titanium-containing material comprises about 0.3% by weight of iron, about 0.25% by weight of oxygen, about 0.1% by weight of carbon, about 0.03% by weight of nitrogen, and about 0.015% by weight of hydrogen.

[0187] In some embodiments, the titanium-containing material has an ultimate tensile strength of about 40,000 psi to about 60,000 psi. In some embodiments, the titanium-containing material has an elongation at break of about 10% to about 50%. In some embodiments, the titanium-containing material has an elastic modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the titanium-containing material has a compressive modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the titanium-containing material has a shear modulus of about 4,000 ksi to about 10,000 ksi. In some embodiments, the titanium-containing material has a Poisson's ratio of about 0.25 to about 0.40. In some embodiments, the titanium-containing material has a tensile strength of about 50 ksi-in. 1 / 2 Up to approximately 65 ksi-in 1 / 2 Annealed fracture toughness. In some embodiments, the titanium-containing material has approximately 40 µΩ. cm to approximately 100 µΩ The resistivity is 1 cm.

[0188] In some embodiments, the size and construction of the positive electrode contact surface containing the titanium-containing material make it resistant to reactions that cause hydroxide formation.

[0189] In some embodiments, after the edge of the planar negative electrode contact surface is bent and the negative electrode contact surface is joined to a portion of the sidewall of the cylindrical housing to seal the button cell, when the outer surface of the planar negative electrode contact surface of the electrochemical button cell is exposed to bodily fluids, substantially no hydroxide is formed during the subsequent approximately 480 minutes.

[0190] According to another embodiment, an electrochemical button cell can be provided, comprising: an active electrochemical assembly including an anode, a separator, and a cathode, wherein the active electrochemical assembly generates an output open-circuit voltage of at least 2.8 volts in the presence of a non-aqueous electrolyte; and a cylindrical container encapsulating the active assembly, the cylindrical container including an anode terminal housing and a cathode terminal housing, with an electrically insulating gasket disposed between them, the anode terminal housing being electrically connected to the anode, and the cathode terminal housing being electrically connected to the cathode. In some embodiments, the cathode terminal housing is composed of a first material comprising more than about 95% by weight of titanium, or more than about 99% by weight of titanium. In some embodiments, a circumferential edge portion of the anode terminal housing is bent or rolled to attach the anode terminal housing to the cylindrical container. In some embodiments, the anode terminal housing is composed of a second material different from the first material (such as stainless steel).

[0191] In some embodiments, the second material comprises stainless steel. In some embodiments, the first material comprises less than about 0.5 wt% iron, less than about 0.5 wt% oxygen, less than about 0.5 wt% carbon, less than about 0.5 wt% nitrogen, and less than about 0.5 wt% hydrogen, wherein the balance or substantially all of the composition is titanium. In some embodiments, the first material comprises about 0.3 wt% iron, about 0.25 wt% oxygen, about 0.1 wt% carbon, about 0.03 wt% nitrogen, and about 0.015 wt% hydrogen, wherein the balance or substantially all of the composition is titanium.

[0192] In some embodiments, the first material has an ultimate tensile strength of about 40,000 psi to about 60,000 psi. In some embodiments, the first material has an elongation at break of about 10% to about 50%. In some embodiments, the first material has an elastic modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the first material has a compressive modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the first material has a shear modulus of about 4,000 ksi to about 10,000 ksi. In some embodiments, the first material has a Poisson's ratio of about 0.25 to about 0.40. In some embodiments, the first material has a strength of about 50 ksi-in 1 / 2 Up to approximately 65 ksi-in 1 / 2 Annealed fracture toughness. In some embodiments, the first material has approximately 40 µΩ. cm to approximately 100 µΩ The resistivity is 1 cm.

[0193] According to another embodiment, a method for manufacturing or forming a casing for an electrochemical coin cell can be implemented. In some embodiments, the method includes: forming a first contact surface for the electrochemical coin cell from a first sheet composed of a first material containing more than about 99% by weight titanium; forming a cylindrical casing cup from a second sheet composed of a second material, the cylindrical casing cup including a substantially flat bottom and sidewalls circumferentially formed around the substantially flat bottom, the substantially flat bottom forming a second contact surface for the electrochemical coin cell, the substantially flat bottom and the sidewalls forming an inner volume; disposing an active electrochemical component within the inner volume of the cylindrical casing cup, the active electrochemical component including an anode, a separator, and a cathode, wherein the active electrochemical component is configured to generate an output open-circuit voltage of at least 2.8 volts in the presence of a non-aqueous electrolyte; and sealing the active electrochemical component within the inner volume of the electrochemical coin cell by engaging the circumferential edge of the first contact surface to one or more portions of the sidewalls of the cylindrical casing cup to electrically communicate the first and second contact surfaces with the active electrochemical component. In some embodiments, the circumferential edge of the first contact surface is engaged to one or more portions of the sidewall of the cylindrical housing cup by bending or curling the circumferential edge of the first contact surface or one or more portions of the sidewall of the cylindrical housing cup.

[0194] In some embodiments, the dimensions and configuration of the first contact surface composed of the first material are such that it is resistant to reactions that produce hydroxides during exposure to bodily fluids. In some embodiments, the first material is different from the second material. In some embodiments, the second material comprises stainless steel. In some embodiments, the first material comprises less than about 0.5 wt% iron, less than about 0.5 wt% oxygen, less than about 0.5 wt% carbon, less than about 0.5 wt% nitrogen, and less than about 0.5 wt% hydrogen, wherein the balance or substantially all of the composition is titanium. In some embodiments, the first material comprises about 0.3 wt% iron, about 0.25 wt% oxygen, about 0.1 wt% carbon, about 0.03 wt% nitrogen, and about 0.015 wt% hydrogen, wherein the balance or substantially all of the composition is titanium.

[0195] In some embodiments, the first material has an ultimate tensile strength of about 40,000 psi to about 60,000 psi. In some embodiments, the first material has an elongation at break of about 10% to about 50%. In some embodiments, the first material has an elastic modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the first material has a compressive modulus of about 10,000 ksi to about 20,000 ksi. In some embodiments, the first material has a shear modulus of about 4,000 ksi to about 10,000 ksi. In some embodiments, the first material has a Poisson's ratio of about 0.25 to about 0.40. In some embodiments, the first material has a strength of about 50 ksi-in 1 / 2 Up to approximately 65 ksi-in 1 / 2 Annealed fracture toughness. In some embodiments, the first material has approximately 40 µΩ. cm to approximately 100 µΩ The resistivity is 1 cm.

[0196] In some embodiments, the method may further include: coating a portion or all of the first material or the first contact surface with a nickel-containing surface coating.

[0197] Benefiting from the teachings given in the foregoing description and accompanying drawings, those skilled in the art will conceive of many modifications and other embodiments of the embodiments set forth herein. Therefore, it is to 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, although exemplary embodiments have been described in the foregoing description and accompanying drawings with respect to certain exemplary combinations of elements and / or functions, it should be recognized that different combinations of elements and / or functions can be provided by alternative embodiments without departing from the scope of the appended claims. In this regard, combinations of elements and / or functions different from those explicitly described above are also contemplated, for example, as may be set forth in some of the appended claims. Although specific terms are used herein, they are used only in a general and descriptive sense and not for limiting purposes.

[0198] Unless otherwise stated, all numerical values ​​used in the specification and claims to indicate amounts of components, reaction conditions, etc., should be understood to be modified by the term "about" in all cases. Therefore, unless indicated to the contrary, the numerical parameters given in this specification and the appended claims are approximate values ​​that may vary depending on the desired properties sought to be obtained through this application. Generally, when referring to amounts of measurable values ​​such as weight, time, dosage, etc., the term "about," as used herein, is intended to cover variations relative to the specified amount of ±20% in one instance, ±10% in another, ±5% in yet another, ±1% in yet another, and ±0.1% in yet another, because such variations are suitable for carrying out the disclosed methods.

[0199] All instances and / or implementations are to be considered non-limiting throughout this disclosure. Furthermore, no inferences should be drawn regarding implementations discussed herein in relation to those not discussed herein, except for purposes of reducing space and redundancy. For example, it is to be understood that the logical and / or topological structure of any combination of data stream sequences, program components (sets of components), other components, and / or any current feature set as described in the figures and / or throughout is not limited to a fixed order of operation and / or arrangement, but any disclosed order is exemplary, and this disclosure considers all equivalents, regardless of order. Furthermore, it is to be understood that these features and steps are not limited to sequential execution, but can be executed asynchronously, concurrently, in parallel, simultaneously, synchronously, etc., as contemplated by this disclosure. Therefore, some of these features may contradict each other, as they cannot coexist in a single implementation. Similarly, some features apply to one aspect of the innovation but not to others. Moreover, this disclosure includes other innovations that are disclosed and may not be explicitly 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 on the disclosure as defined by the embodiments, examples, and claims, or limitations on equivalents of the embodiments, examples and / or claims. It should be understood that various embodiments or portions of various embodiments of the coin cell battery pack described herein can be implemented according to the specific needs and / or characteristics of the electrochemical battery, such as a coin cell battery pack, etc., achieving great flexibility and customization. For example, aspects of the coin cell battery can be modified to allow for greater voltage output, allow for rechargeable coin cells, or allow for different battery pack form factors or battery pack configurations having the same or similar contacts or terminals formed from those titanium-containing materials as described herein, with necessary modifications. Although various embodiments and discussions of titanium-containing terminals and their formation methods relate to coin cells and other electrochemical devices, it should be understood that the embodiments described herein can be readily configured and / or customized for a wide variety of other applications and / or embodiments, such as cylindrical battery packs, pouch battery packs, etc.

Claims

1. A housing for an electrochemical button cell, the housing comprising: A housing having a flat wall and sidewalls, the sidewalls extending from one or more edges of the flat wall to form a housing tank; and A planar conductive portion, which is joined to the sidewall of the housing to form an inner cavity configured to house the active components of an electrochemical coin cell, the planar conductive portion comprising more than approximately 95% by weight titanium. in, In the case where a bend is formed in a planar conductive portion, the bend has a bend radius of approximately 100% to approximately 500% of the thickness of the planar conductive portion, and the planar conductive portion is free of or substantially free of cracks and microcracks.

2. The housing of claim 1, wherein the housing or the planar conductive portion comprises more than about 99% by weight of titanium.

3. The housing of claim 2, wherein the housing or the planar conductive portion comprises less than about 0.5% by weight of iron, less than about 0.5% by weight of oxygen, less than about 0.5% by weight of carbon, less than about 0.5% by weight of nitrogen, and less than about 0.5% by weight of hydrogen.

4. The housing of claim 3, wherein the housing or the planar conductive portion comprises about 0.3% by weight of iron, about 0.25% by weight of oxygen, less than or equal to about 0.08% by weight of carbon, about 0.03% by weight of nitrogen, and about 0.015% by weight of hydrogen.

5. The housing of claim 1, wherein the housing or the planar conductive portion has an ultimate tensile strength of about 30,000 psi to about 60,000 psi.

6. The housing of claim 1, wherein the housing or the planar conductive portion has an elongation at break of about 20% to about 50%.

7. The housing of claim 1, wherein the housing or the planar conductive portion is a positive electrode can having an elongation of more than about 20% at room temperature.

8. The housing of claim 1, wherein the housing or the planar conductive portion has approximately 40 µΩ. cm to approximately 100µΩ The resistivity is 1 cm.

9. The housing of claim 1, wherein when engaged with the sidewall of the housing, the outer peripheral portion of the planar conductive portion bends outward toward the plane of the remaining portion of the planar conductive portion by about 60 degrees to about 160 degrees.

10. The housing of claim 1, wherein one or more of the housing or the planar conductive portion comprises a surface portion, the surface portion comprising one or more of the following: TiN, Ti2N, or TiC.

11. The housing of claim 8, wherein one or more of the housing or the planar conductive portion comprises a nickel-containing surface coating, such that the resistivity is reduced to less than about 50 µΩ. cm.

12. The housing of claim 1, wherein the housing or the planar conductive portion comprises a material resistant to reactions that cause hydroxide formation.

13. The housing of claim 4, wherein the housing or the planar conductive portion further comprises one or more of the following: about 0.05% by weight of ruthenium, about 0.5% by weight of nickel, less than or equal to about 0.3% by weight of iron, less than or equal to about 0.10% by weight of oxygen, less than or equal to about 0.08% by weight of carbon, less than or equal to about 0.03% by weight of nitrogen, and less than or equal to about 0.015% by weight of hydrogen.

14. An electrochemical button cell, comprising: A cylindrical outer shell, the cylindrical outer shell including a positive electrode contact surface and a sidewall formed circumferentially around the positive electrode contact surface, wherein the cylindrical outer shell defines an internal volume; Anode material disposed within the first part of the inner volume; Cathode material disposed within the second part of the inner volume; A diaphragm is disposed within the inner volume between the anode material and the cathode material; An electrolyte material disposed within an internal volume and configured to transport ions between an anode material and a cathode material; and The device includes a planar positive electrode contact surface containing titanium material, which is disposed within or adjacent to an inner volume, such that the anode material, cathode material, separator, and electrolyte material are encapsulated within the inner volume. A portion of the sidewall is joined to the edge of the planar negative electrode contact surface to seal the inner volume of the cylindrical outer shell. The thickness of the planar positive electrode contact surface is approximately 0.1 mm to approximately 0.5 mm, and The radius of curvature at the edge of the planar positive electrode contact surface is approximately 200% equal to or less than the thickness of the planar positive electrode contact surface relative to the sidewall of the cylindrical shell.

15. A method for manufacturing a casing for an electrochemical button cell, the method comprising: A first contact surface for an electrochemical button cell is formed from a first sheet, the first sheet being composed of or encapsulated in a first material, the first material containing more than about 99% by weight of titanium; A cylindrical shell cup is formed from a second sheet, the second sheet being composed of a second material, the cylindrical shell cup including a substantially flat bottom and sidewalls formed circumferentially around the substantially flat bottom, the substantially flat bottom forming a second contact surface for the electrochemical button cell, the substantially flat bottom and the sidewalls forming an inner volume; An active electrochemical component is disposed within the inner volume of a cylindrical shell cup, the active electrochemical component comprising an anode, a diaphragm, and a cathode, wherein the active electrochemical component is configured to generate an output open-circuit voltage of at least 2.8 volts in the presence of a non-aqueous electrolyte; as well as By joining the circumferential edge of the first contact surface to one or more portions of the sidewall of the cylindrical housing cup, the first and second contact surfaces are electrically connected to the active electrochemical component, thereby sealing the active electrochemical component within the internal volume of the electrochemical coin cell. The circumferential edge of the first contact surface is joined to one or more portions of the sidewall of the cylindrical shell cup by bending or curling the circumferential edge of the first contact surface or one or more portions of the sidewall of the cylindrical shell cup.

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