Conductive paste

Abstract

A conductive paste is provided that includes a conductive material, a glass frit, and an organic vehicle. The glass frit is prepared from V2O5, TeO2, Bi2O3 and Al2O3. The content of V2O5 is from about 15 wt.% to about 30 wt.%, based on the total weight of the glass frit. Articles containing the conductive paste and methods for using the conductive paste are also provided.

Description

Related applications

[0001] This application is based on and claims priority to U.S. Provisional Patent Application Serial No. 63 / 580,781, filed on September 6, 2023, which is incorporated herein by reference. Background Technology

[0002] Lithium-ion batteries are known to have high energy density and consist of a cathode, anode, separator, and electrolyte. The electrolyte is typically a liquid electrolyte solution. However, liquid electrolyte solutions can be flammable, thus requiring safer battery alternatives. In light of this, solid-state batteries have been developed. Solid-state batteries use a solid electrolyte instead of a liquid electrolyte solution. Compared to liquid electrolyte batteries, solid-state batteries can also have increased capacity.

[0003] Solid-state batteries can be manufactured using different processes. Some of these processes require electroplating material layers under low pH conditions and sintering the material layers at low temperatures. Given this, there is a need for improved conductive materials that can be sintered at lower temperatures and exposed to acidic conditions. Summary of the Invention

[0004] According to one embodiment of this disclosure, a conductive paste is provided, comprising a conductive material, a glass frit, and an organic carrier. The glass frit comprises V₂O₅, TeO₂, Bi₂O₃, and Al₂O₃. Based on the total weight of the glass frit, the V₂O₅ content is from about 15 wt.% to about 30 wt.%.

[0005] According to another embodiment of this disclosure, a method for forming an article of manufacture including a terminal electrode of a battery is provided. The method includes applying a conductive paste to the article of manufacture. The conductive paste includes a conductive material, a glass frit, and an organic carrier. The glass frit includes V₂O₅, TeO₂, Bi₂O₃, and Al₂O₃. The content of V₂O₅ is from about 15 wt.% to about 30 wt.%. The method includes heating the conductive paste to a firing temperature below about 450°C.

[0006] According to another embodiment of this disclosure, a conductive paste is provided, comprising a conductive material, a glass frit, and an organic carrier. The conductive paste exhibits a resistivity of approximately 3.5 mohm / sq. to less than approximately 8 mohm / sq. when fired at temperatures below 450°C and is acid-resistant.

[0007] Other features and aspects of this disclosure are described in more detail below. Attached Figure Description

[0008] The entire and illustrative disclosure of this specification, including its best mode, which will be readily apparent to those skilled in the art, is set forth in greater detail in the remainder of the specification with reference to the accompanying drawings, in which:

[0009] Figure 1 This is a cross-sectional view of a battery according to an embodiment of this disclosure;

[0010] Figure 2 This is a cross-sectional view of a battery according to an embodiment of this disclosure; and

[0011] Figure 3 This is a flowchart of an example method for forming an electrode according to an embodiment of this disclosure.

[0012] Reference numerals used repeatedly in this specification and drawings are intended to indicate the same or similar features or elements disclosed herein. Detailed Implementation

[0013] Those skilled in the art will understand that this discussion is merely a description of exemplary embodiments and is not intended to limit the broader aspects of this disclosure.

[0014] Generally, this disclosure relates to a conductive paste that exhibits excellent adhesion and is acid-resistant even when fired at lower firing temperatures (e.g., below 450°C). The conductive paste comprises a conductive material in an organic carrier and a glass frit. The glass frit is a lead-free glass frit comprising V₂O₅, TeO₂, Bi₂O₃, and Al₂O₃. Based on the total weight of the glass frit, the V₂O₅ content is from about 15 wt.% to about 30 wt.%. The conductive paste exhibits a resistivity of about 3.5 mohm / sq. to less than about 8 mohm / sq. when fired at temperatures below 450°C and is acid-resistant.

[0015] A conductive paste can be applied to a battery (e.g., a solid-state battery) and fired to form electrodes (e.g., terminal electrodes) thereon. Therefore, this disclosure also provides a method for forming terminal electrodes of a battery. The method includes applying a conductive paste to an article of article. The conductive paste comprises a conductive material in an organic carrier and a glass frit. The glass frit is a lead-free glass frit comprising V₂O₅, TeO₂, Bi₂O₃, and Al₂O₃. Based on the total weight of the glass frit, the V₂O₅ content is from about 15 wt.% to about 30 wt.%. The method includes heating the conductive paste to a firing temperature below about 450°C.

[0016] By selectively controlling the specific concentrations and properties of the components of the conductive paste, the inventors of this invention have discovered that the resulting conductive paste can be effectively fired at lower temperatures (e.g., below 450°C), exhibiting excellent adhesion even at such low firing temperatures, and is acid-resistant.

[0017] The embodiments disclosed herein will now be described in more detail. I. conductive paste a. Conductive materials

[0018] As described above, conductive pastes include conductive materials. The conductive materials disclosed herein are not subject to any particular limitation, provided they do not adversely affect the technical effects of this disclosure. Conductive materials may include those with a conductivity of 7.00 × 10⁻⁹ Kelvin at 293 Kelvin, as described in the embodiments. 6 Siemens per meter (S / m) or higher, and in another embodiment, conductivity of 8.50 × 10⁻⁶ Kelvin at 293 Kelvin. 6 S / m or higher, and in another embodiment, conductivity of 1.00 × 10⁻⁶ at 293 Kelvin. 7 S / m or higher, and in another embodiment, conductivity of 4.00 × 10⁻⁶ at 293 Kelvin. 7 Conductive materials with an S / m or higher.

[0019] In an embodiment, the conductive material may be a metal powder selected from the group consisting of: aluminum (Al, 3.64 × 10⁻⁶). 7 S / m), nickel (Ni, 1.45 × 10 7 S / m), copper (Cu, 5.81 × 10 7 S / m), silver (Ag, 6.17 × 10 7 S / m), gold (Au, 4.17 × 10⁻⁶) 7 S / m), molybdenum (Mo, 2.10 × 10 7 S / m), magnesium (Mg, 2.30 × 10 7 S / m), tungsten (W, 1.82 × 10⁻⁶) 7 S / m), cobalt (Co, 1.46 × 10 7 S / m), Zinc (Zn, 1.64 × 10⁻⁶) 7 S / m), Platinum (Pt, 9.43 × 10⁻⁶) 6 S / m), palladium (Pd, 9.5 × 10⁻⁶) 6 (S / m), its alloys and mixtures thereof. In another embodiment, the conductive material may be selected from the group consisting of: silver, gold, copper, their alloys and mixtures thereof.

[0020] In the embodiments, the conductive material may be silver. When silver is used as the conductive material, it may be in the form of silver metal, silver derivatives, and / or mixtures thereof. Examples of silver derivatives include silver oxide (Ag2O), silver salts (such as silver chloride (AgCl), silver nitrate (AgNO3), silver acetate (AgOOCCH3), silver trifluoroacetate (AgOOCCF3), or silver phosphate (Ag3PO4)), silver-coated composite materials or silver-based alloys with a silver layer on their surface, etc.

[0021] Conductive materials can be in powder form (e.g., spherical shapes, flakes, irregular shapes, and / or mixtures thereof) or colloidal suspensions, etc. The particle size (D50) of the conductive powder can be from about 0.5 μm to about 12 μm in one embodiment, from about 1 μm to about 10.5 μm in another embodiment, and from about 1.3 μm to about 9.5 μm in yet another embodiment. The particle size (D50) can be measured using a Microtrac model S-3500 via laser diffraction scattering. Mixtures of metals with different average particle sizes, particle size distributions, or shapes can also be used.

[0022] In one embodiment, the specific surface area (SA) of the conductive powder can be approximately 1.5 m². 2 / g to approximately 8 m 2 / g, in another embodiment it can be about 1.9 m 2 / g to approximately 6.9 m 2 / g, and in another embodiment it can be about 2.2 m 2 / g to approximately 5.5 m 2 / g. Specific surface area can be measured using the BET method with Monosorb™ from Quantachrome Instruments Corporation.

[0023] In one embodiment of this disclosure, the conductive material is present in the conductive paste at a content of about 50 wt.% to about 80 wt.%, such as about 55 wt.% to about 70 wt.%, or about 60 wt.% to about 75 wt.%. In another embodiment, the conductive material is present in the conductive paste at a content of about 50 wt.% to about 65 wt.%. In other embodiments, the conductive material is present in the conductive paste at a content of about 60 wt.% to about 80 wt.%. b. Glass material

[0024] The conductive paste disclosed herein includes glass frit. The glass frit may comprise glass particles in powder form (e.g., spherical, flake, irregular, and / or mixtures thereof). The conductive paste may comprise about 1 wt.% to about 25 wt.% of glass frit, such as about 5 wt.% to about 15 wt.% of glass frit, such as about 2 wt.% to about 20 wt.% of glass frit. In embodiments, the conductive paste may comprise about 1 wt.% to about 10 wt.% of glass frit. In other embodiments, the conductive paste may comprise about 10 wt.% to about 25 wt.% of glass frit.

[0025] The glass frit may include metal oxides. For example, in an embodiment, the glass frit may include transition metal oxides. Suitable transition metal oxides include those that can be formed from oxygen and one or more transition metals. For example, suitable transition metal oxides may include vanadium oxides, particularly vanadium pentoxide (V₂O₅). In an embodiment, the glass frit contains only one transition metal oxide, which includes vanadium pentoxide (V₂O₅). In another embodiment, the glass frit contains only two transition metal oxides, which include V₂O₅ and tungsten oxide (WO₃). Based on the total weight of the glass frit, the glass frit may include about 15 wt.% to about 30 wt.% of V₂O₅, such as about 18 wt.% to about 28 wt.% of V₂O₅, such as about 20 wt.% to about 25 wt.% of V₂O₅. In an embodiment, the glass frit includes about 15 wt.% to about 25 wt.% of V₂O₅. In other embodiments, the glass frit includes about 20 wt.% to about 30 wt.% of V₂O₅. In some embodiments, the glass flot comprises about 6 wt.% to about 10 wt.%, such as about 7 wt.% to about 8 wt.%, such as about 7.5 wt.% to about 8.4 wt.% of WO3, based on the total weight of the glass flot.

[0026] In such embodiments, the glass frit is substantially free of all other transition metal oxides. Non-limiting examples of such transition metal oxides include scandium oxide, titanium oxide (e.g., titanium dioxide (TiO2)), chromium oxide, magnesium oxide, iron oxide, cobalt oxide, nickel oxide, copper oxide, zinc oxide, yttrium oxide, zirconium oxide, niobium oxide, molybdenum oxide, technetium oxide, ruthenium oxide, rhodium oxide, palladium oxide, silver oxide, cadmium oxide, hafnium oxide, tantalum oxide, tungsten oxide, rhenium oxide, osmium oxide, iridium oxide, platinum oxide, gold oxide, mercury oxide, α oxide, β oxide, β oxide, β oxide, β oxide, β oxide, and combinations or mixtures thereof. Specifically, in embodiments, the glass frit does not include any transition metal oxides that form cations, such as zinc oxide. For example, the inventors of this invention have discovered that using specific combinations of oxides produces glass frits that contribute to excellent acid resistance compared to other formulations. Such acid resistance can be used for end-use in batteries, such as as end electrodes in solid-state batteries.

[0027] In embodiments, the glass frit comprises a quasi-metal oxide. For example, the glass frit may include tellurium oxide (TeO2). In embodiments, the only quasi-metal oxide present in the glass frit is tellurium oxide. In other embodiments, the only quasi-metal oxide present in the glass frit includes TeO2 and silicon dioxide (SiO2). In other embodiments, the glass frit is substantially free of boron oxide, silicon oxide, germanium oxide, arsenic oxide, antimony oxide, and mixtures thereof. Based on the total weight of the components of the glass frit, the TeO2 content may be from about 40 wt.% to about 70 wt.%, such as from about 45 wt.% to about 65 wt.%, such as from about 50 wt.% to about 60 wt.%. In embodiments, the TeO2 content may be from about 40 wt.% to about 60 wt.%. In other embodiments, the TeO2 content may be from about 50 wt.% to about 70 wt.%. In the embodiments, the SiO2 content is about 1 wt.% to about 5 wt.%, for example, about 2 wt.% to about 4 wt.%, for example, about 2 wt.% to about 3 wt.%, based on the total weight of the glass frit.

[0028] The glass frit may include one or more post-transition metal oxides. Suitable post-transition metal oxides may include aluminum oxides (e.g., Al₂O₃), bismuth oxides (e.g., Bi₂O₃), and combinations or mixtures thereof. In embodiments, the glass frit may be substantially free of other post-transition metal oxides besides aluminum oxides and bismuth oxides. For example, the glass frit may be substantially free of gallium oxides, indium oxides, tin oxides, thallium oxides, lead oxides, polonium oxides, astatine oxides, and mixtures or combinations thereof.

[0029] Based on the total weight of the glass frit, the glass frit may include about 10 wt.% to about 30 wt.%, such as about 15 wt.% to about 25 wt.%, such as about 12 wt.% to about 20 wt.% of Bi2O3. In an embodiment, based on the total weight of the glass frit, the glass frit may include about 20 wt.% to about 30 wt.% of Bi2O3. Based on the total weight of the glass frit, the glass frit may include about 1 wt.% to about 12 wt.%, such as about 5 wt.% to about 10 wt.%, such as about 7 wt.% to about 12 wt.% of Al2O3. In an embodiment, based on the total weight of the glass frit, the glass frit may include about 1 wt.% to about 5 wt.% of Al2O3. In other embodiments, based on the total weight of the glass frit, the glass frit may include about 5 wt.% to about 12 wt.% of Al2O3.

[0030] In some embodiments, the glass frit may include alkali metal oxides. Suitable alkali metal oxides include lithium oxide, sodium oxide, potassium oxide, and rubidium oxide. In embodiments, the glass frit may include lithium oxide (Li₂O) and is substantially free of all other alkali metal oxides. When alkali metal oxides are present, their content in the glass frit is from about 0.1 wt.% to about 2 wt.%, for example, from about 0.5 wt.% to about 2 wt.%, for example, from about 0.6 wt.% to about 1 wt.%. In other embodiments, the glass frit is substantially free of alkali metal oxides.

[0031] In the embodiments, the glass frit comprises a combination of metal oxides, including vanadium pentoxide, tellurium oxide, bismuth oxide, and aluminum oxide. Unbound by any theory, the glass frit composition as described increases the adhesion and original strength of the conductive paste after printing onto the surface of the article and firing, while providing increased acid resistance to the fired paste.

[0032] As described above, in the embodiments, the glass frit is a lead-free glass frit that does not contain lead or lead components. Specifically, the glass frit is substantially free of any lead and its derivatives (e.g., lead oxides, such as lead monoxide (PbO), lead dioxide (PbO2), or lead tetroxide (Pb3O4), etc.).

[0033] The softening point of the glass frit can be from about 200°C to about 500°C, for example, from about 200°C to about 400°C, for example, from about 250°C to about 400°C, for example, from about 200°C to about 300°C.

[0034] In another embodiment, the particle size (D50) of the glass frit can be from about 0.1 μm to 15 μm, for example, from about 0.5 μm to about 11 μm, for example, from 1.0 μm to 6.8 μm, for example, from about 1.5 μm to 4.5 μm. In other embodiments, the particle size of the glass frit can be from about 0.1 μm to about 10 μm or from about 5 μm to about 15 μm. The particle size (D50) can be measured using a Microtrac model S-3500 via laser diffraction scattering. c. Organic carrier

[0035] Conductive pastes may include an organic carrier. For example, conductive materials and glass frits can be mixed with an organic carrier to form a conductive paste. The organic carrier can be in liquid or viscous form to facilitate mixing. A suitable organic carrier allows the conductive materials and glass frits to be uniformly dispersed therein and has an appropriate viscosity to deliver the conductive materials and glass frits to the surface of the article, such as by screen printing, stencil printing, etc. The provided conductive paste provides good drying rates and excellent burn-off characteristics even at lower firing temperatures (e.g., below 450°C).

[0036] The organic carrier may include an organic polymer and a solvent. A variety of inert adhesive materials can be used as the organic polymer. The organic polymer may be selected from the group consisting of: ethyl cellulose, ethyl hydroxyethyl cellulose, rosin, phenolic resins, polymethyl methacrylates of lower alcohols, monobutyl ether of ethylene glycol monoacetate, and mixtures thereof. Based on the total weight of the organic carrier, the content of the organic polymer may be from about 5 wt.% to about 40 wt.%, for example, from about 10 wt.% to about 30 wt.%, for example, from about 6 wt.% to about 20 wt.%, for example, from about 20 wt.% to about 40 wt.%.

[0037] The solvent can be selected from the group consisting of: texanol, ester alcohols, terpineol, kerosene, dibutyl phthalate, butyl carbitol, butyl carbitol acetate, dibutyl carbitol, hexanediol, diesters, and mixtures thereof. The solvent is selected based on the solubility of the organic polymer. Based on the total weight of the organic carrier, the solvent content can be from about 60 wt.% to about 95 wt.%, for example, from about 50 wt.% to about 85 wt.%, for example, from about 60 wt.% to about 75 wt.%, for example, from about 70 wt.% to about 95 wt.%, for example, from about 80 wt.% to about 95 wt.%. In the examples, the organic carrier comprises a mixture of ethyl cellulose and texanol.

[0038] The organic carrier may optionally include organic additives. Organic additives may be one or more of thickeners, stabilizers, viscosity modifiers, surfactants, wetting agents, thixotropic agents, and other conventional additives (e.g., colorants, preservatives, or oxidants). The amount of organic additive depends on the desired properties of the resulting conductive paste. The choice of additives is not limited, as long as they do not adversely affect the technical effects disclosed herein. d. Resistivity

[0039] The conductive paste disclosed herein can have a resistivity of about 3.5 mohm / sq. to less than about 8 mohm / sq. when fired at temperatures below about 450°C. In embodiments, the conductive paste can have a resistivity of about 3.7 mohm / sq. to about 7 mohm / sq., such as about 4 mohm / sq. to about 6 mohm / sq., or such as about 4 mohm / sq. to about 5 mohm / sq. when fired at temperatures below about 450°C. In other embodiments, the conductive paste can have a resistivity of about 4 mohm / sq. to about 7.5 mohm / sq., such as about 4.2 mohm / sq. to about 6.3 mohm / sq., or such as about 4.4 mohm / sq. to about 5.1 mohm / sq. when fired at temperatures below about 450°C. In other embodiments, the conductive paste, when fired at a temperature of about 400°C, can have a resistivity of about 4 mohm / sq. to about 6.5 mohm / sq., for example, about 4 mohm / sq. to about 6 mohm / sq., or for example, about 4.9 mohm / sq. to about 5.6 mohm / sq. In other embodiments, the conductive paste, when fired at a temperature of about 350°C, can have a resistivity of about 5.5 mohm / sq. to about 7.5 mohm / sq., for example, about 6.1 mohm / sq. to about 6.6 mohm / sq., or for example, about 5.8 mohm / sq. to about 7.2 mohm / sq.

[0040] The resistivity can be measured using the following method. A conductive paste is applied in a serpentine line pattern onto an alumina substrate containing 96% wt.% Al₂O₃. The line pattern has a width of 0.5 mm, a length of 135.5 mm, and a thickness of 10 μm. The line pattern is then dried in a box oven at 150°C for approximately 10 minutes. The line pattern is then fired in a box oven at the firing temperature for 10 minutes. The resistivity of the line pattern is then measured using a digital multimeter (Model 2100, Keithley Instruments, Inc.). e. Acid resistance

[0041] In the embodiments, the conductive paste disclosed herein is acid-resistant. As used herein, “acid-resistant” refers to an acid resistance test in which nine (9) 2 mm × 2 mm squares of conductive paste are printed onto an alumina substrate containing 96 wt.% Al2O3. Each square has a width of 2 mm, a length of 2 mm, and a thickness of 10 μm. The squares are then dried in a box oven at 150°C for 10 minutes. The squares are then fired in a box oven at a firing temperature for 10 minutes. After firing, the substrate is immersed in a tin sulfonate plating solution with a pH of about 1 for 5 minutes. The tin sulfonate plating solution is at a temperature of about 18°C ​​to 24°C. The substrate containing the squares is then removed from the plating solution and washed with distilled water. Once dried, each square is exposed to tape (e.g., Scotch® tape), and the number of resulting squares peeled off from the alumina substrate is counted.

[0042] The conductive paste is considered "acid-resistant" in which fewer than 4 squares, such as fewer than 3 squares, such as fewer than 2 squares, such as fewer than 1 square, or such as 0 squares, are peeled off from the substrate. In other words, the conductive paste can be "acid-resistant" in which less than 35 wt.%, such as less than about 20 wt.%, such as less than about 10 wt.%, such as less than about 5 wt.%, such as less than about 1 wt.%, or such as about 0 wt.%, of the fired conductive paste is removed from the alumina substrate by tape (e.g., Scotch® tape) after exposure to a tin sulfonate plating solution at pH 1 and a temperature of about 18°C ​​to 24°C. II. Products

[0043] A conductive paste can be applied to one or more articles and fired to form a conductive layer thereon. Notably, the conductive paste disclosed herein can be applied to an article and then fired to form a conductive layer thereon. For example, the conductive paste can be used in a wide range of applications where lower firing temperatures are desired (e.g., batteries, solar energy, etc.). For instance, the conductive paste disclosed herein can be fired at temperatures below 450°C while maintaining excellent adhesion and acid resistance, as described in the examples provided below.

[0044] Given that the conductive paste is acid-resistant, in this embodiment, the conductive paste can be used in articles for batteries, such as solid-state batteries. In this embodiment, the conductive paste can be used on the solid-state battery 10 to form one or more end electrodes 15. For example, as Figure 1As shown, a conductive paste can be applied and fired to produce the terminal electrode 15 as shown. For example, the solid-state battery 10 may include one or more electrolyte layers 16 and one or more internal electrodes 17 arranged in a stacked configuration as shown. The ends of each electrolyte layer 16 and internal electrode layer 17 may be coupled to the terminal electrode 15. In practice, a conductive paste can be applied to the ends of the electrolyte layer 16 and internal electrode layer 17 and fired to produce the terminal electrode 15. As shown, additional plating layers (e.g., a first plating layer 20 and a second plating layer 22) can be placed on the outer surface of the terminal electrode 15. Plating layers 20, 22 may include conductive materials, such as metals. In embodiments, plating layers include nickel, tin, or combinations thereof.

[0045] To form the plating layers 20, 22 on the battery 10, the process typically requires an electroplating process to deposit nickel and tin materials on the terminal electrodes 15. Such electroplating processes are carried out under acidic conditions and require exposing the components of the battery 10 to a pH of approximately 1 to 4. Therefore, the conductive paste disclosed herein provides excellent acid resistance once fired, and given this acid resistance, it can be used for terminal electrode formation.

[0046] The solid-state battery 10 can be surface-mounted onto a suitable substrate 30, such as Figure 2 As shown. The substrate material can include any conductive, dielectric, or insulating material. Suitable substrates include printed circuit boards. Further, as... Figure 2 As shown, one or more mounting pads 40 may be provided between the product 10 and the substrate 30. The product 10 may be placed on the mounting pads 40, and solder 50 may be applied to securely bond the product to the substrate 30. III. method

[0047] Figure 3 A flowchart depicts an example method for forming an article of articles (100) according to this disclosure.

[0048] In (102), the method includes applying a conductive paste to an article of articles. The conductive paste may include a conductive material and a glass frit dispersed within an organic carrier. The conductive paste may include the materials described herein. In embodiments, the conductive material may include a metal, such as silver. The glass frit may include various metal oxides. In embodiments, the glass frit includes V₂O₅, TeO₂, Bi₂O₃, and Al₂O₃. Based on the total weight of the glass frit, the V₂O₅ content may be from about 15 wt.% to about 30 wt.%. The organic carrier may include a polymer and a solvent. Based on the total weight of the organic carrier, the organic carrier may include from about 5 wt.% to about 40 wt.% of a polymer and from about 60 wt.% to about 95 wt.% of a solvent. The conductive paste may include about 20 wt.% to about 40 wt.% (e.g., about 28 wt.%) of an organic carrier, about 50 wt.% to about 70 wt.% of a conductive material (e.g., about 62 wt.%), and about 5 wt.% to about 15 wt.% (e.g., about 10 wt.%) of a glass frit.

[0049] In embodiments, the conductive paste may be disposed on one or more components of the battery (e.g., a solid-state battery) as disclosed. For example, the conductive paste may be disposed on one or more of the electrolyte layer, electrodes, or other structures on the solid-state battery.

[0050] Optionally, in (103), the method includes drying the conductive paste prior to firing. For example, the conductive paste can be dried in an oven at a drying temperature for a desired amount of time. The drying temperature can range from about 100°C to about 200°C, such as about 150°C. The drying time can also vary, from about 5 minutes to about 1 hour, from about 10 minutes to about 50 minutes, from about 15 minutes to about 45 minutes, from about 20 minutes to about 40 minutes, and / or about 30 minutes. Drying can be performed in any suitable oven or heater.

[0051] In (104), the method includes heating the conductive paste to a firing temperature. In embodiments, the firing temperature can be in the range of about 350°C to about 600°C. However, in embodiments, the firing temperature is below about 450°C. The conductive paste can be fired for a duration ranging from about 5 minutes to about 1 hour, about 10 minutes to about 50 minutes, about 15 minutes to about 45 minutes, about 20 minutes to about 40 minutes, and / or about 30 minutes. In embodiments, the firing time is about 10 minutes. Firing can be performed in any suitable oven or heater. After firing, electrodes are formed on the article by the conductive paste.

[0052] In this embodiment, an electrode formed from a conductive paste is formed on the solid-state battery and may be an end electrode. In this embodiment, given the solid electrolyte material and other internal electrode layers, it is desirable not to expose other materials to high firing temperatures, such as firing temperatures exceeding 600°C. Therefore, in (104), the firing temperature may include temperatures below 450°C, minimizing additional heat to other components on or within the solid-state battery, which can reduce material alteration or quality degradation of other battery materials.

[0053] Optionally, in (105), the method includes exposing the electrode formed from the conductive paste to additional processing conditions. For example, in the case where the conductive paste is used to form the terminal electrode of a battery, the electrode may be exposed to an additional electroplating process. This process may expose the formed electrode to a low pH environment, such as an environment with a pH between 1 and 4. Additionally, the electrode may be exposed to further sintering or firing steps to sinter or fire other material layers on the article. In such embodiments, the electrode may be exposed to an additional firing step at a firing temperature in the range of about 220°C to about 600°C for a period of time ranging from about 5 minutes to about 1 hour.

[0054] In the embodiments, even when exposed to low pH (approximately 1 to 4) environments or other conditions, After annealing at temperatures ranging from 220°C to 600°C, electrodes formed from conductive pastes still exhibit superior adhesion to components on articles (e.g., batteries) compared to electrodes formed from conductive pastes made from other materials. Such results are further illustrated in the following examples.

[0055] Furthermore, the article of manufacture including electrodes may be exposed to soldering. In such embodiments, the electrodes may be exposed to soldering at a soldering temperature in the range of about 220°C to about 260°C for a period of time in the range of about 20 seconds to about 40 seconds. In this embodiment, the article of manufacture containing electrodes formed from the conductive paste disclosed herein may be coupled to a substrate (e.g., a printed circuit board). Test methods

[0056] According to this disclosure, the following methods may be used. resistivity test

[0057] The resistivity of the conductive paste disclosed herein can be measured using the following method. The conductive paste is arranged in a serpentine line pattern (e.g., printed) on an alumina substrate containing 96 wt.% Al₂O₃. The serpentine line pattern has a width of 0.5 mm, a length of 135.5 mm, and a thickness of 10 μm. The line pattern is then dried in a box oven at 150°C for 10 minutes. After drying, the line pattern is fired in a box oven at a firing temperature for 10 minutes. After firing, the resistivity of the line pattern is measured using a digital multimeter (Model 2100, Keysley Instruments). Acid resistance test

[0058] The acid resistance of the conductive paste disclosed herein can be measured by the following method. Nine (9) 2 mm × 2 mm squares of conductive paste are printed onto an alumina substrate containing 96 wt.% Al2O3. Each square has a width of 2 mm, a length of 2 mm, and a thickness of 10 μm. The squares are then dried in a box oven at 150°C for 10 minutes. After drying, the squares are fired in a box oven at a firing temperature for 10 minutes. The firing temperature can be in the range of about 350°C to about 600°C. After firing, the substrate is immersed in a tin sulfonate plating solution with a pH of about 1 and a temperature of about 18°C ​​to 24°C for 5 minutes. The substrate containing the squares is then removed from the plating solution and washed with distilled water. Once dried, each square is exposed to tape (e.g., Scotch® tape), and the number of squares obtained peeled off from the alumina substrate is counted. Example

[0059] This disclosure is further illustrated through, but not limited to, the following examples.

[0060] Comparative examples (C1 to C3) and experimental examples (E1 to E9) for preparing glass frits are shown in Table 1 below. Table 1

[0061] Silver powder and glass frits (C1 to C3 and E1 to E9) were dispersed in an organic carrier in a mixer and homogenized by a three-roll mill. The silver powder was a first Ag powder (particle size (D50): approx. 0.8 μm, SA: approx. 0.9 μm). 2 / g) and second Ag powder (particle size (D50): approx. 1.6 μm, SA: approx. 0.7 μm) 2 The mixture comprises 9 wt.% (g) of polymer and 91 wt.% solvent, based on the weight of the organic carrier. The conductive paste comprises approximately 28 wt.% organic carrier, 62% conductive material, and 10% glass frit.

[0062] Conductive pastes with control and experimental glass frits were screen-printed in a square pattern onto an alumina substrate (25 mm long, 25 mm wide, 0.6 mm thick) to test initial adhesion and acid resistance. The pattern consisted of nine squares, each with a width of 2 mm, a length of 2 mm, and a thickness of 10 μm. After printing, the squares were dried in a box oven at 150°C for approximately 10 minutes. The squares were then fired in a box oven at different firing temperatures, including 350°C, 400°C, 450°C, and 600°C, for 10 minutes each. All nine squares were then exposed to Scotch® tape before acid exposure, and the tape was then peeled off by hand. The number of squares peeled off with Scotch® tape was then counted. The initial adhesion results are shown in Tables 2 through 5.

[0063] The acid resistance of the square pattern was also measured. To measure acid resistance, an alumina substrate with a square pattern was immersed in a tin sulfonate plating solution at pH 1 for 5 minutes. The alumina substrate was then removed and dried. All nine squares were then exposed to Scotch® tape, which was then peeled off by hand. The number of squares peeled off with Scotch® tape was counted. The acid resistance results are shown in Tables 2 through 5.

[0064] The resistivity (Rs) of the conductive paste was also measured to see if the material could have a sufficiently low resistivity. The conductive paste was printed onto an alumina substrate in a serpentine line pattern. The line pattern was 0.5 mm wide, 135.5 mm long, and 10 μm thick. After printing, the line pattern was dried in a box oven at 150°C for approximately 10 minutes. The line pattern was then fired in a box oven at different firing temperatures, including 350°C, 400°C, 450°C, and 600°C, for 10 minutes each. The resistivity of the line pattern was measured using a digital multimeter (Model 2100, Keysley Instruments). The results are shown in Tables 2 through 5. Table 2 Table 3 Table 4 Table 5

[0065] Compared to the comparative examples after acid exposure, the number of peeled squares was significantly lower in the experimental examples. The resistivity of the experimental examples remained at an acceptablely low level compared to the comparative examples. Furthermore, all comparative examples (C1 to C3) peeled after acid exposure at firing temperatures below 450°C, while none of the experimental examples (E1 to E9) peeled after acid exposure. definition

[0066] As used herein, ranges and quantities can be expressed as “about” a specific value or range. “About” is intended to also include the exact quantity. Thus, “about 5%” means “about 5%” and also “5%”. “About” means within typical experimental error for the intended application or purpose.

[0067] As used herein, “optional” or “optionally” means that an event or condition described below may or may not occur, and the description includes instances where said event or condition occurs and instances where said event or condition does not occur. For example, an optional component in a method or composition means that the component may or may not be present in the method or composition.

[0068] As used herein, “adhesion” refers to the property of a material’s surface to adhere to or bond to the surface of another material. Adhesion can be measured by the Scotch® tape test disclosed herein or by any other acceptable test, such as by ASTM D3359-08.

[0069] As used herein, the term “substantially non-existent” means present in no more than negligible trace amounts and covers complete absence (e.g., 0 mol% to 0.01 mol%).

[0070] Chemical elements are discussed in this disclosure using their common chemical abbreviations (such as those found in the periodic table). For example, hydrogen is represented by its common chemical abbreviation H; helium by its common chemical abbreviation He; and so on.

[0071] Unless otherwise specified or explicitly implied by the context of the reference, all references to the singular characteristics or limitations of this disclosure shall include the corresponding plural characteristics or limitations, and vice versa.

[0072] The methods and compositions disclosed herein (including their components) may include, constitute, or substantially constitute the essential elements and limitations of this disclosure as set forth herein.

[0073] These and other modifications and variations of this disclosure may be practiced by those skilled in the art without departing from the spirit and scope thereof. Furthermore, it should be understood that aspects of the various embodiments may be interchanged in whole or in part. Moreover, those skilled in the art will understand that the foregoing description is merely illustrative and not intended to limit this disclosure (as further described in the appended claims). Claims (as amended under Article 19 of the Treaty) 1. A conductive paste, the conductive paste comprising: Conductive materials; The glass frit comprises V₂O₅, TeO₂, Bi₂O₃, and Al₂O₃, wherein the V₂O₅ content is from about 15 wt.% to about 30 wt.% based on the total weight of the glass frit; and Organic carrier. 2. The conductive paste of claim 1, wherein the glass material comprises about 40 wt.% to about 70 wt.% of TeO2. 3. The conductive paste of claim 1, wherein the glass material comprises 10 wt.% to 30 wt.% Bi2O3. 4. The conductive paste of claim 1, wherein the glass frit comprises about 1 wt.% to about 12 wt.% Al2O3. 5. The conductive paste of claim 1, wherein the conductive material comprises a metal. 6. The conductive paste of claim 5, wherein the metal comprises silver. 7. The conductive paste of claim 1, wherein the organic carrier comprises an organic polymer and an alcohol. 8. The conductive paste of claim 7, wherein the organic polymer comprises ethyl cellulose. 9. The conductive paste of claim 1, wherein the conductive paste comprises about 55 wt.% to about 70 wt.% of the conductive material. 10. The conductive paste of claim 1, wherein the conductive paste comprises about 5 wt.% to about 15 wt.% of the glass frit. 11. The conductive paste of claim 1, wherein the conductive paste comprises about 20 wt.% to about 40 wt.% of the organic carrier. 12. The conductive paste of claim 1, wherein the paste is substantially lead-free. 13. The conductive paste of claim 1, wherein the paste is substantially free of one or more other transition metal oxides. 14. The conductive paste of claim 1, wherein the conductive paste exhibits a resistivity of about 3.5 mohm / sq. to less than about 8 mohm / sq. when fired at a temperature below 450°C. 15. An article of manufacture comprising a battery, wherein the conductive paste of claim 1 is applied to the battery to form one or more end electrodes. 16. A method for forming an article of manufacture including a terminal electrode of a battery, the method comprising: A conductive paste is applied to the article, the conductive paste comprising: Conductive materials; The glass frit comprises V₂O₅, TeO₂, Bi₂O₃, and Al₂O₃, wherein the content of V₂O₅ is from about 15 wt.% to about 30 wt.%; and an organic carrier; and The conductive paste is heated to a firing temperature below approximately 450°C. 17. The method of claim 16, wherein the glass material comprises about 40 wt.% to about 70 wt.% of TeO2. 18. The method of claim 16, wherein the glass material comprises 10 wt.% to 30 wt.% Bi2O3. 19. The method of claim 16, wherein the glass frit comprises about 1 wt.% to about 12 wt.% of Al2O3. 20. The method of claim 16, wherein the conductive material comprises silver.

Claims

1. A conductive paste, the conductive paste comprising: Conductive materials; The glass frit comprises V₂O₅, TeO₂, Bi₂O₃, and Al₂O₃, wherein the V₂O₅ content is from about 15 wt.% to about 30 wt.% based on the total weight of the glass frit; and Organic carrier.

2. The conductive paste as described in claim 1, wherein, The glass frit comprises approximately 40 wt.% to approximately 70 wt.% of TeO2.

3. The conductive paste as described in claim 1, wherein, The glass frit comprises 10 wt.% to 30 wt.% Bi2O3.

4. The conductive paste as described in claim 1, wherein, The glass frit comprises about 1 wt.% to about 12 wt.% of Al2O3.

5. The conductive paste as described in claim 1, wherein, The conductive material includes metals.

6. The conductive paste as described in claim 5, wherein, This metal includes silver.

7. The conductive paste as described in claim 1, wherein, The organic carrier includes organic polymers and alcohols.

8. The conductive paste as described in claim 1, wherein, The organic polymer includes ethyl cellulose.

9. The conductive paste of claim 1, wherein the conductive paste comprises about 55 wt.% to about 70 wt.% of the conductive material.

10. The conductive paste of claim 1, wherein the conductive paste comprises about 5 wt.% to about 15 wt.% of the glass frit.

11. The conductive paste of claim 1, wherein the conductive paste comprises about 20 wt.% to about 40 wt.% of the organic carrier.

12. The conductive paste according to claim 1, wherein, This paste is essentially lead-free.

13. The conductive paste according to claim 1, wherein, The paste is essentially free of one or more other transition metal oxides.

14. The conductive paste according to claim 1, wherein, The conductive paste exhibits a resistivity of approximately 3.5 mohm / sq. to less than approximately 8 mohm / sq. when fired at temperatures below 450°C.

15. An article comprising a battery, wherein, The conductive paste as described in claim 1 is applied to the battery to form one or more end electrodes.

16. A method for forming an article of manufacture including a terminal electrode of a battery, the method comprising: A conductive paste is applied to the article, the conductive paste comprising: Conductive materials; The glass frit comprises V₂O₅, TeO₂, Bi₂O₃, and Al₂O₃, wherein the content of V₂O₅ is from about 15 wt.% to about 30 wt.%; and Organic carriers; and The conductive paste is heated to a firing temperature below approximately 450°C.

17. The method of claim 16, wherein, The glass frit comprises approximately 40 wt.% to approximately 70 wt.% of TeO2.

18. The method of claim 16, wherein, The glass frit comprises 10 wt.% to 30 wt.% Bi2O3.

19. The method of claim 16, wherein, The glass frit comprises about 1 wt.% to about 12 wt.% of Al2O3.

20. The method of claim 16, wherein, The conductive material includes silver.

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