Methods for making and using current collectors

Abstract

Disclosed herein are methods for making current collectors for battery applications. In one embodiment, method for making a current collector includes: mixing first metal particles, a second metal particles, and a carrier fluid to make an ink, where the first metal particles are selected from silicon, zirconium, magnesium, silver, gold, platinum, indium, where the first metal particles have an average cross-sectional diameter from about 3 nm to about 100 nm, where the second metal particle is selected from copper, aluminum, nickel, titanium, and steel, where the second metal particles have an average cross-sectional diameter from about 5 μm to about 50 μm, and where the carrier fluid is selected from water, toluene, ethanol, isopropanol, acetone, hexane, N-methyl-2- pyrrolidone, acetonitrile, dimethyl sulfoxide, dimethylformamide, tetrahydrofuran, and N,Ndimethylformamide; printing, by direct ink writing, one or more layers of the ink on one or more substrates using a printing nozzle to make a current collector.

Description

PATENT Attorney Docket No. 33987-5PCT METHODS FOR MAKING AND USING CURRENT COLLECTORSCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims benefit of priority under 35 U.S.C. §119(e) of U.S. Serial No.63 / 776,771, filed 14-March-2025, the entire contents of which is incorporated herein by reference in its entirety.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] This invention was made with Government support under Contract No. DE-AC52-07NA27344 awarded by the United States Department of Energy. The Government has certain rights in the invention.BACKGROUNDField

[0003] Composite current collectors made of metal nanoparticles and copper through additive manufacturing techniques that include direct-ink-writing of compositions are described.Description of the Related Art

[0004] Commercial lithium-ion (Li-ion) batteries based on graphite anodes are becoming limited by their energy densities. In order to satisfy the large market demands for higher energy¬ density and lighter rechargeable batteries, high-capacity metallic lithium is one of the most promising anode candidates to replace graphite, currently used anode electrode in Li-ion batteries, enabling higher energy density for the next-generation rechargeable Li metal batteries (LMBs) or all-solid state batteries (ASSBs) with Li metal as the anode. However, most electrolytes are not stable against Li metal anode, leading to electrolyte decomposition, interfacial side reactions with liquid or solid electrolytes, low Coulombic efficiency and specific capacity. The aggressive Li metal chemistry makes it challenging to serve as an anode in LMB and / or ASSBs. The current approach to overcoming these challenges is to try to achieve a uniform Li deposition during Li plating, protecting lithium metal with organic or inorganic layers. More recently, attention has been moved to the structural design of Li anodes, to inhibit the growth of Li dendrites. Lowering the local current density along the anode surface Li-metal alloy anodes to improve the stability with the electrolyte, porous lithium-metal anode (i.e., lithium-metal powder, and lithium-coated polymeric matrix) could retard the onset of dendrite nuclei and reduce the rate of dendrite growth. The14930-9759-7825 v.lPATENT Attorney Docket No. 33987-5PCT employment of anode host could also undermine the volume change of lithium, which is another significant factor of contributing cell instability, has long been overlooked. However, many of these designs are often accompanied with increased internal resistance and the loss of active materials. The complicated manufacturing process of these nanostructured materials used to date also restricts their practical application. Another promising anode for battery materials applications is silicon, Si, with a theoretical capacity of 3592 mAh g outperforms graphite (372 mAh g ) -the currently prevalent anode material of lithium commercial (Li)-ion batteries. However, silicon's significant volume expansion (>200%) during cycling causes low Coulombic efficiency and poor performance, limiting their commercialization. Despite efforts such as nanostructuring and electrolyte optimization, achieving durable, high-capacity Si anodes remain a vibrant area of research. Moreover, new chemistries have been developed to mitigate electrolyte decomposition with Li metal, such as anode-free battery technology. Anode-free chemistries are promising because of their safety, higher energy density, and lower manufacturing cost compared with Li-ion batteries. However, the stability of Li plating and stripping mechanisms during repeated cycling in anode-fee solid state batteries needs to be greatly improved to obtain a high coulombic efficiency and capacity to realize anode-free battery chemistries.

[0005] Consequently, there is a need to engineer new battery materials to overcome battery performance limitations. For example, engineering new current collectors that can provide stable interfaces for Li plating, inhibit lithium dendrite formation, and mitigate volume expansion due to lithiation / delithiation on Si anode electrodes.SUMMARY

[0006] Provided herein are methods for making current collectors that can be used in battery applications. In one specific embodiment, a method for making a current collector includes: mixing first metal particles, a second metal particles, and a carrier fluid to make an ink, where the first metal particles are selected from silicon, zirconium, magnesium, silver, gold, platinum, indium, where the first metal particles have an average cross-sectional diameter from about 3 nm to about 100 nm, where the second metal particle is selected from copper, aluminum, nickel, titanium, and steel, where the second metal particles have an average cross-sectional diameter from about 5 pm to about 50 pm, and where the carrier fluid is selected from water, toluene, ethanol, isopropanol, acetone, hexane, N-methyl-2-pyrrolidone, acetonitrile, dimethyl sulfoxide, dimethylformamide,24930-9759-7825 v.lPATENT Attorney Docket No. 33987-5PCT tetrahydrofuran, and N,N-dimethylformamide; printing, by direct ink writing, one or more layers of the ink on one or more substrates using a printing nozzle to make a current collector

[0007] In another specific embodiment, a method for using a current collector including: providing a current collector, where the current collector is made by process including: mixing first metal particles, a second metal particles, and a carrier fluid to make an ink, where the first metal particles are selected from silicon, zirconium, magnesium, silver, gold, platinum, indium, where the first metal particles have an average cross-sectional diameter from about 3 nm to about 10 nm, where the second metal particle is selected from copper, aluminum, nickel, titanium, and steel, where the second metal particles have an average cross-sectional diameter from about 5 pm to about 50 pm, and where the carrier fluid is selected from water, toluene, ethanol, isopropanol, acetone, hexane, N-methyl-2-pyrrolidone, acetonitrile, dimethyl sulfoxide, dimethylformamide, tetrahydrofuran, and N,N-dimethylformamide; and printing, by direct ink writing, one or more layers of the ink on one or more substrates using a printing nozzle to make a current collector, where the one or more layers comprise one or more crests and one or more troughs; and charging the current collector, where the charging includes depositing lithium or sodium on the copper substrate with one or more printed layers to make a lithium or sodium-metal alloy on surface of the current collector and subsequently a lithium or sodium metal anode formed in situ during charging on the surface of the current collector.

[0008] In another specific embodiment, a battery cell including: a cathode electrode; one or more electrolytes, where the one or more electrolytes includes: Li ions and / or Na ions; and a current collector made by a process comprising: combining first metal particles, a second metal particles, and a carrier fluid to make an ink, where the first metal particles are selected from silicon, zirconium, magnesium, silver, gold, platinum, indium, where the first metal particles have an average cross-sectional diameter from about 3 nm to about 10 nm, where the second metal particle is selected from copper, aluminum, nickel, titanium, and steel, where the second metal particles have an average cross-sectional diameter from about 5 pm to about 50 pm, and where the carrier fluid is selected from water, toluene, ethanol, isopropanol, acetone, hexane, N-methyl-2-pyrrolidone, acetonitrile, dimethyl sulfoxide, dimethylformamide, tetrahydrofuran, and N,N-dimethylformamide; and printing, by direct ink writing, one or more layers of the ink on a copper substrate using a printing nozzle to make a current collector.34930-9759-7825 v.lPATENT Attorney Docket No. 33987-5PCT

[0009] In this case the composite current collector or hybrid current collector with a 3D copper structure in a Si anode battery will not only provides exceptional electrical conductivity but also acts as a robust structural support to accommodate silicon expansion while maintaining mechanical integrity.DESCRIPTION OF THE DRAWINGS

[0010] For the purposes of promoting an understanding of the principles of the present disclosure, reference can be now made to the embodiments illustrated in the drawings, which are described below. The embodiments disclosed herein are not intended to be exhaustive or limit the present disclosure to the precise form disclosed in the following detailed description. Rather, the embodiments are chosen and described so that others skilled in the art can utilize their teachings. Therefore, no limitation of the scope of the present disclosure is thereby intended.

[0011] FIGURE 1 is a graph of cycle number versus coulombic efficiency for a conventional, comparative Cu foil current collector in a half cell configuration (Cu foil- electrolyte- Li metal).

[0012] FIGURE 2 is a graph showing a voltage 1 versus time plot for the conventional Cu foil current collector in a half cell configuration (Cu foil- electrolyte- Li metal). Highlighting the high overpotential (>0.07 V) (high resistance) of Li deposition on to the current collector (Cu foil).

[0013] FIGURE 3 is a scanning electron microscopy image of conventional Cu foil after 15 h of Li deposition showing uneven Li deposition.

[0014] FIGURE 4 shows an embodiment of direct-ink- writing (DIW) of the ink in solid, spiral, and zig-zag patterns.

[0015] FIGURE 5 is an X-ray diffraction plot of the composite Cu-based current collector material.

[0016] FIGURE 6 is a graph of cycle number versus coulombic efficiency for a 3D Cu-Ag in a half-cell configuration (3D Cu-Ag-electrolyte-Li metal), showing > 700 cycles.

[0017] FIGURE 7 is a graph showing a voltage 1 versus time plot for the 3D Cu-Ag in a half-cell configuration (3D Cu-Ag-electrolyte-Li metal), highlighting the low overpotential (<0.05 V) (low resistance) of Li deposition on to the 3D Cu-Ag composite current collector.

[0018] FIGURE 8 are scanning electron microscopy images of 3D Cu-lwtAg after plating for 15 h, showing guided Li deposition.

[0019] FIGURE 9 are atomic force microscopy images of Cu ink 2D cast, Cu ink 3D pressed, Cu 3D backside, and Cu foil with the table listing the roughness mean (nm) and standard deviation.44930-9759-7825 v.lPATENT Attorney Docket No. 33987-5PCT

[0020] FIGURE 10 shows an embodiments for battery cells that include 3D-Ag-Electrolyte(Gen2)-NMC622 after plating and cycling.

[0021] FIGURE 11 is a graph that shows the rate performance evaluation of a full cell using the 3D Cu-Ag composite current collector (3D Cu-Ag composite current collector-Li platted-electrolyte-NMC622) showing high specific capacity.DETAILED DESCRIPTION

[0022] Current collectors (CC) are substrates for anodes electrode in electrochemical cells. Typically, current collectors are added to every cell that is integrated into a battery. It has been surprisingly and unexpectedly discovered that current collectors made with composite materials that include substrate, micro- and / or nano-sized metal particles can reduce the electrodeposition / electrodissolution overpotentials and improve Coulombic efficiency in half cells and battery performance. While not wanting to be bound by theory, it is believed that the composite materials can improve the Li plating on to the current collector, improve the intercalation mechanism for graphite anodes used in Li-ion batteries while charging, and mitigate accommodate volume expansion in Si anode battery technology.

[0023] In one or more embodiments, the current collector can include, but is not limited to: one or more composite materials, one or more substrates, one or more metal particles, one or more alloys, and combinations thereof. In some embodiments, the composite material can include, but is not limited to: one or more substrates, one or more metal particles, one or more alloys, one or more additives, and combinations thereof. In some embodiments, the composite material can include, but is not limited to: one or more copper substrates and one or more Li / Na-metal alloys. In some embodiments, the composite material can include, but is not limited to: one or more substrates, one or more Li / Na-metal alloys, and one or more layers of lithium metal and combinations thereof. In some embodiments, the composite material can include, but is not limited to: one or more substrates, one or more Li / Na-metal alloys, one or more layers of lithium metal, one or more additives, and combinations thereof.

[0024] In some embodiments, the metal particles can be at least partially incorporated into the volume of the one or more substrates to make a Li / Na-metal alloy. In some embodiments, the Li / Na-metal alloy can be at least partially incorporated into the volume of the one or more substrates to make a composite material. In some embodiments, the current collector can be manufactured in 2D and / or 3D complex architectures. For example, the metal particles of the composite material54930-9759-7825 v.lPATENT Attorney Docket No. 33987-5PCT can be incorporated into the volume of the one or more substrates to make a 2D or a 3D configuration of the composite material. In some embodiments, the current collector can be a 2D object, e.g., a thin layer of composite applied to a substrate. In some embodiments, the current collector can be a 3D object, e.g., a multi-layer object made by multiple layers of direct-inkwriting.

[0025] In some embodiments, the composite material can provide precise mechanical and electrical properties. For example, the Cu-based current collector or composite material can prevent Li dendrite growth and improve cycling stability. In some embodiments, a current collector made from the composite material can improve Li nucleation and eliminates Li dendrite growth, and thus accelerates the development of anode-free batteries (next generation of batteries). The Cu-based current collector made with the composite material can improve the battery performance by facilitating the Li intercalation mechanism taking place in the graphite anode in Li-ion batteries. In some embodiments, the composite material can be tuned so it can improve Li nucleation and growth taking place in anode-free batteries, improving battery performance by providing a higher columbic efficiency and cyclability than conventional current collectors that do not have a composite material. In some embodiments, the composition of the composite current collector can mitigate-overcome Si expansion in silicon anode batteries, to improve cycling performance and capacity. In some embodiments, the current collector made from composite materials can decrease the lithium nucleation overpotential as well as the plating overpotential, thus, decreasing the resistance of the formation of a Li metal film on the surface of the current collector. In some embodiments, the homogeneous formation of Li metal film can improve battery performance.

[0026] Copper (Cu) is a common material used as a current collector on the anode side of a battery. In some embodiments, the composite material can include a copper current collector of Cu + Li / Na-Metal (Si, Zr, Mg, Ag, Au, Pt, and In) alloy fabricated through a scalable and low-cost process that can improve the performance of different battery chemistries. In some embodiments, the metal particles can alloy with the incoming Li+ / Na+ cations during charging, which lowers the nucleation / intercalation barrier in the cell and thus improves performance.

[0027] In some embodiments, current collectors can be made by electrodeposition. When the current collectors are printed, the porosity and structure (dimensions) of the current collector can also be tuned from planar 2D to complex 3D architectures depending on the targeted application64930-9759-7825 v.lPATENT Attorney Docket No. 33987-5PCT which could include printed electronics, energy storage, and thermal conductive applications, such as electromagnetic interference or radio frequency interference shielding.

[0028] In some embodiments, Cu-Si nanoparticles can be used to print 3D hybrid current collectors with different structures via direct ink writing approach to increase the surface area of the CC, increase the solid electrolyte-CC contact area, mitigate-overcome Si volume expansion during charging, and increase the electroactive surface area to improve performance. The Si anode batteries can include a positive electrode (cathode) and a separator including a liquid electrolyte or a solid electrolyte that acts as an ion-conducting medium between the two electrodes. The hybrid composite current collector (Cu-Si) can homogenize Si volume expansion, improving the coulombic efficiency and cyclability of a Si anode battery.

[0029] In some embodiments, Cu-Ag nanoparticles can be used to print 3D current collectors with different structures via direct ink writing approach to increase the surface area of the CC, increase the solid electrolyte-CC contact area, control the volume changes during cycling, and increase the electroactive surface area. For example, it was shown that Cu-Ag nanoparticle compositions can greatly improve the room-temperature performance of anode-free liquid cells (Li-liquid electrolyte- 3D-Cu - Ag NPs) from a Coulombic efficiency of 65 % (conventional CC) to >98% (our CC) for more than 700 cycles without any degradation. Based on the scanning electron microscopy (SEM) characterization, it is shown that the composition as well as the architecture of the Cu CC+ Ag eliminates Li dendrite growth and lowers the Li nucleation barrier, leading to a homogenous formation of Li metal anode. The current collector made from the composite material not only contributes to the realization of the emerging anode-free battery configuration and silicon (Si) anode batteries by mitigating Si volume expansion during cycling, but also improves the Li-intercalation mechanism on to graphite anode used in commercialized Li-ion batteries.

[0030] For anode-free configurations, the cell is composed of a positive electrode (cathode) and electrolyte (liquid or solid) and a current collector, such as Cu, and the negative electrode (anode-Li metal) is formed in-situ while the cell is cycled. The current collector can improve battery performance by lowering the Li nucleation barrier, by spatially controlling Li deposition to avoid Li dendrite growth; as well as it improves Li intercalation mechanism in Li-ion batteries. Due to the electrochemical and mechanical properties of current collector, it can also be utilized in other applications such as in electronics. Current collector made using the composite material can be74930-9759-7825 v.lPATENT Attorney Docket No. 33987-5PCT used in different battery configurations, i.e., Li-ion, anode-free Li-metal, all-solid-state batteries, and flow batteries, lithium-oxygen batteries, Si anode batteries. In some embodiments, the composite materials can provide a homogeneous surface for deposition of Li, inhibiting Li dendrite growth. By spatially controlling the nucleation-deposition of Li, homogeneous Li metal films were obtained, leading to improved battery performance. In some embodiment, the composite current collector can improve battery performance by providing a higher columbic efficiency and cyclability than current collectors that do not have a composite material.

[0031] In some embodiments, the current composite and / or current collectors CC can be used in batteries to provide mechanical stability, smooth Li ion transport, chemical passivation ability, and combinations thereof. The Li-ion batteries can include a positive electrode (cathode) / negative electrode (anode) and a separator including a liquid electrolyte (or a solid electrolyte that serves as a separator as well in all-solid-state batteries) that acts as an ion-conducting medium between the two electrodes. In some embodiments, the composite CC can homogenize the Li deposition onto the current collector, improving the coulombic efficiency and cyclability of an solid-state battery.

[0032] The current collector made from the composite materials can be chemically and electrochemically stable against Li metal (anode), forming an even passivation layer that prevents electrolyte decomposition by the formation of an alloy. In some embodiments, the current collector made from the composite materials can improve in-situ formation of Li metal during charging, thereby improving cycling stability. In some embodiments, the current collector made from the composite materials can stabilize the Li metal anode / electrolyte interface by an alloying approach, allowing for the utilization of super-ionic conductors (solid electrolytes) that are often not stable when compared to Li metal. In some embodiments, the composite material can allow for solid electrolytes, such as sulfide and halide materials, to be incorporated into anode-free all-solid-state batteries by introducing surface chemistry modifications to the current collector.

[0033] In one or more embodiments, the current collector can be made by a process that includes, but is not limited to: mixing first metal particles, a second metal particles, and a carrier fluid to make an ink, where the first metal particles are selected from silicon, zirconium, magnesium, silver, gold, platinum, indium, where the second metal particle is selected from copper, aluminum, nickel, titanium, and steel, where the second metal particles have an average cross-sectional diameter from about 5 pm to about 50 pm and where the carrier fluid is selected from84930-9759-7825 v.lPATENT Attorney Docket No. 33987-5PCT water or water and surfactants, such as Triton x-100 or sodium dodecyl sulfate (SDS), organic solvents, such as toluene, ethanol, isopropanol , acetone, and hexane, and polar aprotic solvents such as N-methyl-2-pyrrolidone (NMP), acetonitrile, dimethyl sulfoxide (DMSO), dimethylformamide (DMF), tetrahydrofuran (THF), and N,N-dimethylformamide (DMF);and printing, by direct ink writing, one or more layers of the ink on one or more substrates using a printer or doctor blade to make a current collector.

[0034] The one or more metal particles can include a first metal particles, second metal particles, third metal particles, four metal particles, and more metal particles. In some embodiments, the first metal particles used to make a current collector can include, are not limited to: copper, lithium, silicon, zirconium, magnesium, silver, gold, platinum, indium, and combinations thereof. In some embodiments, the second metal particles used to make a current collector can include, are not limited to: copper, lithium, silicon, zirconium, magnesium, silver, gold, platinum, indium, and combinations thereof.

[0035] The one or more metal particles can have an average cross-sectional diameter that varies widely. For example, the particles can have an average cross-sectional diameter from a low about 10 nm, about 60 nm, or about 80 nm, to a high of about 140 pm, about 150 pm, or about 300 pm. In another example, the particles can have an average diameter from about 3 nm to about 10 nm, about, 5 pm to about 50 pm, about 20 nm to about 60 microns, 50 nm to about 200 pm, about 50 nm to about 100 nm, about 10 nm to about 500 nm, about 60 nm to about 10 pm, about 65 nm to about 20 pm, about 70 nm to about 110 nm, about 75 nm to about 120 nm, about 80 nm to about 150 nm, about 80 nm to about 150 pm, about 80 nm to about 200 pm, about 100 nm to about 180 pm or about 100 nm to about 300 pm.

[0036] The ink can have a one or more metal content that varies widely. The ink can have a one or more metal content from a low of about 0.1 wt%, about 1.0 wt%, or about 10 wt%, to a high of about 70.0 wt%, about 80.0 wt%, or about 99.0 wt%. In another example, the ink can have a one or more metal content of at least 45.0 wt%, at least 50.0 wt%, or at least 55.0 wt%. In another example, the ink can have a one or more metal content from about 5.0 wt% to about 99.0 wt%, about 3.0 wt% to about 7.0 wt%, about 8.0 wt% to about 22.0 wt%, about 10.0 wt% to about 30.0 wt%, about 15.0 wt% to about 25.0 wt%, about 18.0 wt% to about 22.0 wt%, about 20.0 wt% to about 80.0 wt%, about 25.0 wt% to about 75.0 wt%, about 69.0 wt% to about 75.0 wt%, about 68.0 wt% to about 82.0 wt%, about 72.0 wt% to about 86.0 wt%, about 50.0 wt% to about 73.094930-9759-7825 v.lPATENT Attorney Docket No. 33987-5PCT wt%, about 33.0 wt% to about 48.0 wt%, about 60.0 wt% to about 70.0 wt%, about 71.0 wt% to about 81.0 wt%, about 20.0 wt% to 30.0 wt%, about 50.0 wt% to about 60.0 wt%, about 70.0 wt% to about 80.0 wt%, about 75.0 wt% to about 85.0 wt%, about 78.0 wt% to about 85.0 wt%, or about 79.0 wt% to about 92.0 wt%. The weight percent of the one or more metal particles in the ink can be based on the total weight of the ink; based on the total weight of the first particles and second particles; based on the total weight of the first particles, second particles, and the one or more additives; based on the total weight of the first particles, second particles, and the one or more carrier fluids; or based on the total weight of the first particles, second particles, the one or more carrier fluids, and the one or more additives.

[0037] The ink can have a first metal content that varies widely. The ink can have a first metal content from a low of about 0.1 wt%, about 1.0 wt%, or about 10 wt%, to a high of about 70.0 wt%, about 80.0 wt%, or about 99.0 wt%. In another example, the ink can have a first metal content of at least 45.0 wt%, at least 50.0 wt%, or at least 55.0 wt%. In another example, the ink can have a first metal content from about 5.0 wt% to about 99.0 wt%, about 3.0 wt% to about 7.0 wt%, about 8.0 wt% to about 22.0 wt%, about 10.0 wt% to about 30.0 wt%, about 15.0 wt% to about 25.0 wt%, about 18.0 wt% to about 22.0 wt%, about 20.0 wt% to about 80.0 wt%, about 25.0 wt% to about 75.0 wt%, about 69.0 wt% to about 75.0 wt%, about 68.0 wt% to about 82.0 wt%, about 72.0 wt% to about 86.0 wt%, about 50.0 wt% to about 73.0 wt%, about 33.0 wt% to about 48.0 wt%, about 60.0 wt% to about 70.0 wt%, about 71.0 wt% to about 81.0 wt%, about 20.0 wt% to 30.0 wt%, about 50.0 wt% to about 60.0 wt%, about 70.0 wt% to about 80.0 wt%, about 75.0 wt% to about 85.0 wt%, about 78.0 wt% to about 85.0 wt%, or about 79.0 wt% to about 92.0 wt%. The weight percent of the first metal particles in the ink can be based on the total weight of the ink; based on the total weight of the first particles and second particles; based on the total weight of the first particles, second particles, and the one or more additives; based on the total weight of the first particles, second particles, and the one or more carrier fluids; or based on the total weight of the first particles, second particles, the one or more carrier fluids, and the one or more additives.

[0038] The ink can have a second metal content that varies widely. The ink can have a second metal content from a low of about 0.1 wt%, about 1.0 wt%, or about 10 wt%, to a high of about 70.0 wt%, about 80.0 wt%, or about 99.0 wt%. In another example, the ink can have a second metal content of at least 45.0 wt%, at least 50.0 wt%, or at least 55.0 wt%. In another example,104930-9759-7825 v.lPATENT Attorney Docket No. 33987-5PCT the ink can have a second metal content from about 5.0 wt% to about 99.0 wt%, about 3.0 wt% to about 7.0 wt%, about 8.0 wt% to about 22.0 wt%, about 10.0 wt% to about 30.0 wt%, about 15.0 wt% to about 25.0 wt%, about 18.0 wt% to about 22.0 wt%, about 20.0 wt% to about 80.0 wt%, about 25.0 wt% to about 75.0 wt%, about 69.0 wt% to about 75.0 wt%, about 68.0 wt% to about 82.0 wt%, about 72.0 wt% to about 86.0 wt%, about 50.0 wt% to about 73.0 wt%, about 33.0 wt% to about 48.0 wt%, about 60.0 wt% to about 70.0 wt%, about 71.0 wt% to about 81.0 wt%, about 20.0 wt% to 30.0 wt%, about 50.0 wt% to about 60.0 wt%, about 70.0 wt% to about 80.0 wt%, about 75.0 wt% to about 85.0 wt%, about 78.0 wt% to about 85.0 wt%, or about 79.0 wt% to about 92.0 wt%. The weight percent of the second metal particles in the ink can be based on the total weight of the ink; based on the total weight of the first particles and second particles; based on the total weight of the first particles, second particles, and the one or more additives; based on the total weight of the first particles, second particles, and the one or more carrier fluids; or based on the total weight of the first particles, second particles, the one or more carrier fluids, and the one or more additives.

[0039] The one or more carrier fluids can include but is not limited to, but are not limited to: water; toluene, ethanol, isopropanol, acetone, and hexane, and polar aprotic solvents such as N-methyl-2-pyrrolidone (NMP), acetonitrile, dimethyl sulfoxide (DMSO), dimethylformamide (DMF), tetrahydrofuran (THF), and N,N-dimethylformamide (DMF);and combinations thereof. The one or more carrier fluids can include one or more surfactants.

[0040] The ink can have a content of the one or more carrier fluids that varies widely. For example, the ink can have a content of the one or more carrier fluids from a low of about 0.1 wt%, about 1.0 wt%, or about 10 wt%, to a high of about 70.0 wt%, about 80.0 wt%, or about 99.0 wt%. In another example, ink can have a content of the one or more carrier fluids content of at least 0.4 wt%, at least 2.0 wt%, or at least 5.0 wt%. In another example, the ink can have a content of the one or more carrier fluids can have an additives content from about 0.2 wt% to about 2.0 wt%, 0.5 wt% to about 1.5 wt%, about 1.0 wt% to about 3.0 wt%, about 5.0 wt% to about 95.0 wt%, about 1.0 wt% to about 3.0 wt%, about 25.0 wt% to about 75.0 wt%, about 20.0 wt% to about 80.0 wt%, about 69.0 wt% to about 75.0 wt%, about 68.0 wt% to about 82.0 wt%, about 72.0 wt% to about 86.0 wt%, about 50.0 wt% to about 73.0 wt%, about 33.0 wt% to about 48.0 wt%, about 60.0 wt% to about 70.0 wt%, about 71.0 wt% to about 81.0 wt%, about 20.0 wt% to 30.0 wt%, about 50.0 wt% to about 60.0 wt%, or about 70.0 wt% to about 99.0 wt%. The weight percent of the one or114930-9759-7825 v.lPATENT Attorney Docket No. 33987-5PCT more carrier fluids in the ink can be based on the total weight of the ink; based on the total weight of the first particles, second particles, and one or more carrier fluids; based on the total weight of the first particles, second particles, one or more carrier fluids, and the one or more additives; based on the total weight of the first particles, second particles, one or more carrier fluids, and one or more surfactants; or based on the total weight of the first particles, second particles, the one or more carrier fluids, one or more surfactant, and the one or more additives.

[0041] The one or more surfactants can include, but is not limited to: emulsifying, nonemulsifying, anionic, cationic, nonionic, amphoteric, and combinations thereof. In some embodiments, the one or more surfactants can include, but is not limited to: sodium dodecyl sulfate (SDS), one or more alpha olefin sulfonate, one or more hydroxysultaines, and combinations thereof. In some embodiments, the one or more surfactants can include, but is not limited to one or more of the following: one or more alpha olefin sulfonate, one or more hydroxysultaines, nonylphenol ethoxylated (C13 / 9 moles EO); ethoxylated alcohol; trideceth-9 (6-10 moles EO); sodium alpha olefin sulfonate (C12-C16); 1 -dodecanesulfonic acid, hydroxy-, sodium salt; lauramine oxide (Cl 2); sodium lauryl ether sulfate (2 moles EO); sodium lauryl sulfate; cocamidopropyl hydroxy sultaine (C12); / / -octadecyl disodium sulfosuccinate; dioctyl sodium Sulfosuccinate; cocamidopropyl betaine; coco glucoside (C8-C14); decyl glucoside (C8-C10); glyceryl laurate; cocamidopropylamine oxide; calcium dodecylbenzenesulphonate; sodium cocoate; lauramidopropyl hydroxysultaine; cocamide diethanolamine; dodecyldimethylamine oxide; polyoxyethylene 20 sorbitan trioleate (20 moles EO); sorbitan monolaurate (20 moles EO); and combinations thereof. The one or more alpha olefin sulfonate can include, but is not limited to one or more of the following: alpha olefin sulfonate can include carbon chains of varying lengths. For example, the alpha olefin sulfonate can include carbon chain lengths of C8, C9, CIO, CH, C12, C13, C14, C15, C16, C17, C18, and mixtures thereof. In another example, the alpha olefin sulfonate can include sodium alpha olefin sulfonate; dodecane- 1 -sulfonic acid (C12) CAS 30965-85-6; 1 -dodecanesulfonic acid, hydroxy-, sodium salt CAS 128824-30-6; and combinations thereof. The one or more surfactants can include commercially available surfactants. For example, the one or more surfactants can include TRITON® X-100, made by Dow Chemical Company headquartered in Midland, Michigan.

[0042] The ink can have a content of the one or more surfactants that varies widely. For example, the ink can have a content of the one or more surfactants from a low of about 0.1 wt%,124930-9759-7825 v.lPATENT Attorney Docket No. 33987-5PCT about 1.0 wt%, or about 10 wt%, to a high of about 70.0 wt%, about 80.0 wt%, or about 99.0 wt%. In another example, the ink can have a content of the one or more surfactants can have an additives content of at least 0.4 wt%, at least 2.0 wt%, or at least 5.0 wt%. In another example, the ink can have a content of the one or more surfactants from about 0.2 wt% to about 2.0 wt%, 0.5 wt% to about 1.5 wt%, about 1.0 wt% to about 3.0 wt%, about 5.0 wt% to about 95.0 wt%, about 1.0 wt% to about 3.0 wt%, about 25.0 wt% to about 75.0 wt%, about 20.0 wt% to about 80.0 wt%, about 69.0 wt% to about 75.0 wt%, about 68.0 wt% to about 82.0 wt%, about 72.0 wt% to about 86.0 wt%, about 50.0 wt% to about 73.0 wt%, about 33.0 wt% to about 48.0 wt%, about 60.0 wt% to about 70.0 wt%, about 71.0 wt% to about 81.0 wt%, about 20.0 wt% to 30.0 wt%, about 50.0 wt% to about 60.0 wt%, or about 70.0 wt% to about 99.0 wt%. The weight percent of the one or more surfactants in the ink can be based on the total weight of the ink; based on the total weight of the first particles, second particles, and one or more carrier fluids; based on the total weight of the first particles, second particles, one or more carrier fluids, and the one or more additives; based on the total weight of the first particles, second particles, one or more carrier fluids, and one or more surfactants; or based on the total weight of the first particles, second particles, the one or more carrier fluids, one or more surfactant, and the one or more additives.[00043J The one or more additives an including but are not limited to: one or more electrolytes, one or more alloying materials, one or more metal particles, one or more binders, one or more electrolyte additives, one or more solvents, one or more plasticizers, one or more dispersants, one or more rheology modifiers, one or more inorganic salts, and combinations thereof. The one or more binders can include, but are not limited to, polyvinylidene fluoride.

[0044] The composite material can have a content of the one or more additives that can varies widely. For example, the composite material can have an additives content from a low of about 0.1 wt%, about 1.0 wt%, or about 10 wt%, to a high of about 70.0 wt%, about 80.0 wt%, or about 99.0 wt%. In another example, the composite material can have an additives content of at least 0.4 wt%, at least 2.0 wt%, or at least 5.0 wt%. In another example, the composite material can have an additives content from about 0.2 wt% to about 2.0 wt%, 0.5 wt% to about 1.5 wt%, about 1.0 wt% to about 3.0 wt%, about 5.0 wt% to about 95.0 wt%, about 1.0 wt% to about 3.0 wt%, about 25.0 wt% to about 75.0 wt%, about 20.0 wt% to about 80.0 wt%, about 69.0 wt% to about 75.0 wt%, about 68.0 wt% to about 82.0 wt%, about 72.0 wt% to about 86.0 wt%, about 50.0 wt% to about 73.0 wt%, about 33.0 wt% to about 48.0 wt%, about 60.0 wt% to about 70.0 wt%, about134930-9759-7825 v.lPATENT Attorney Docket No. 33987-5PCT 71.0 wt% to about 81.0 wt%, about 20.0 wt% to 30.0 wt%, about 50.0 wt% to about 60.0 wt%, or about 70.0 wt% to about 99.0 wt%. The weight percent of the one or more additives in the composite material can be based on the total weight of the composite material; or based on the total weight of the one or more substrates, one or more metal particles, one or more copper substrates, one or more Li / Na-metal alloying materials, and one or more additives.

[0045] In some embodiments, the method of making the current collector can include one or more reaction mixtures. The one or more reaction mixtures can be heated to a wide range of temperatures. For example, the reaction mixture can be heated to a temperature and pressure to make metal alloy. In another example, the reaction mixture can be heated to a temperature from a low of about 0 °C, about 15 °C, or about 25 °C, to a high of about 1,000 °C, about 2,000 °C, or about 4,000 °C. For example, the reaction mixture can be heated to a temperature from about 25 °C to about 28 °C, about 25 °C to about 35 °C, about 25 °C to about 90 °C, about 30 °C to about 45 °C, about 40 °C to about 90 °C, about 43 °C to about 78 °C, about 400 °C to about 900 °C, about 100 °C to about 2,000 °C, about 1,000 °C to about 3,000 °C, or about 600 °C to about 4,000 °C. In another example, the reaction mixture can be at room temperature.

[0046] The one or more reaction mixtures can be reacted and / or stirred for a reaction time that varies widely. For example, the reaction mixture can be heated to a temperature to make metal alloy. In another example, the reaction mixture can be reacted and / or stirred for a reaction time from a short of about 30 s, about 120 s, or about 300 s, to a long of about 1 h, about 24 h, or about 72 h. For example, the reaction mixture can be from about 1 min to about 15 min, about 5 min to about 45 min, about 1 h to about 7 h, about 1 h to about 12 h, about 5 h to about 15 h, about 10 h to about 24 h, about 12 h to about 17 h, about 12 h to about 24 h, about 22 h to about 50 h, or about 24 h to about 72 h.

[0047] In one or more embodiments, the method for using a current collector can include, but is not limited to: providing a current collector, where the current collector is made by process including: mixing first metal particles, a second metal particles, and a carrier fluid to make an ink, where the first metal particles are selected from silicon, zirconium, magnesium, silver, gold, platinum, indium, where the second metal particle is selected from copper, aluminum, nickel, titanium, and steel, and where the carrier fluid; and printing, by direct ink writing, one or more layers of the ink on a = substrate using a printing nozzle to make a current collector, where the one or more layers include one or more crests and one or more troughs; and charging the current144930-9759-7825 v.lPATENT Attorney Docket No. 33987-5PCT collector, where the charging includes depositing lithium on the copper substrate with one or more printed layers.

[0048] In one or more embodiments, the current collector can be made using direct-ink- writing. For example, the ink can include, but is not limited to: the one or more metal particles and one or more Li / Na alloying materials. In some embodiments, the ink can be applied through a printing nozzle to at least partially coat a substrate, such as copper foil. The ink made using the composite material can have a viscosity that varies widely. For example, the ink can have a viscosity from a low of about 0.0074 cP, about 1.0 cP, or about 100,000 cP, to a high of about 250,000 cP, about 900,000 cP, or about 2,500,000 cP. In another example, the composite material can have a viscosity from about 0.0074 cP to about 5 cP, about 10 cP to about 200,000 cP, about 100 cP to about 10,000 cP, about 10,000 cP to about 100,000 cP, about 1,000 cP to about 250,000 cP, about 10,000 cP to about 50,000 cP, about 100,000 cP to about 250,000 cP, about 620,000 cP to about 850,000 cP, about 700,000 cP to about 750,000 cP, about 700,000 cP to about 800,000 cP, about 650,000 cP to about 855,000 cP, about 700,000 cP to about 800,000 cP, about 500,000 cP to about 1,000,000 cP, or about 500,000 cP to about 2,500,000 cP. In another example, the ink can have a viscosity from about 100 Pa s to about 10 mPa s, about 200 Pa s to about 1 mPa s, about 300 Pa s to about 2 mPa s, about 100 Pa s to about 5 mPa s and about 600 Pa s to about 8 mPa s. The viscosity of the ink made using the composite material can be measured on a viscosimeter at various temperatures, such as 25 °C, 40 °C, 60 °C, and 100 °C.

[0049] The ink can be applied to a substrate with a thickness or height that varies widely. For example, the ink can have a thickness or height from a low of about 1.0 nm, about 10.0 nm, or 50.0 microns, to a high of about 100.0 microns, about 500.0 microns, or about 2.0 mm. In another example, the ink can have a thickness from about 1.0 nm to about 10.0 mm, about 2.0 nm to about 200.0 mm, about 10.0 nm to about 100.0 mm, about 5.0 nm to about 250.0 mm, about 2.0 microns to about 200 microns, about 5.0 microns to about 50.0 microns, about 10.0 microns to about 100.0 microns, about 20.0 microns to about 250.0 microns, about 30.0 microns to about 500.0 microns, about 300.0 microns to about 900,0 microns, about 100.0 microns to about 1.0 mm, about 200,0 microns to about 1.0 mm, or about 1.0 mm to about 2.0 mm.

[0050] In some embodiments, Li metal can be uniformly deposited on the crests of the 3D Cu flowed by deposition on the troughs of the 3D. In some embodiments, the ink can create structures that guide Li deposition. The Li metal can be formed on a substrate with a thickness or height that154930-9759-7825 v.lPATENT Attorney Docket No. 33987-5PCT varies widely For example, the Li metal can be formed on a substrate with a thickness from a low of about 1,0 nm, about 10,0 nm, or 50.0 microns, to a high of about 100.0 microns, about 500.0 microns, or about 2.0 mm. In another example, Li metal can be formed on a substrate with a thickness from about 1.0 nm to about 10.0 mm, about 2.0 nm to about 200.0 mm, about 10.0 nm to about 100.0 mm, about 5.0 nm to about 250.0 mm, about 2.0 microns to about 20.0 microns, about 5.0 microns to about 50.0 microns, about 10.0 microns to about 100.0 microns, about 20.0 microns to about 250.0 microns, about 30.0 microns to about 500.0 microns, about 300.0 microns to about 900.0 microns, about 100.0 microns to about 1.0 mm, about 200.0 microns to about 1.0 mm, or about. 1.0 mm to about 2.0 ram.

[0051] The composite material can have an electronic conductivity that varies widely. For example, the composite material can have an ionic conductivity from a low of about 0.2 millisiemens per centimeter (mS / cm) to a high of about 9 * 107S / m at room temperature.

[0052] The composite material can have a Young's modulus that varies widely. For example, the composite material can have Young's modulus from a low of about 0.5 GPa, about 1.75 GPa, or about 2.0 MPa, to a high of about 120 GPa. In another example, the composite material can have Young's modulus from about 0.5 GPa to about 7.0 GPa, about 130 GPa.

[0053] In one or more embodiments, the current collectors can be used in a wide variety of applications. For example, the composite materials can be used as a current collector in Li-ion batteries. In another example, the composite current collectors can be used in anode-free solid state batteries. In another example, the current collectors can be used in printed electronics, such as printed circuit boards, Cu clad laminates, thermal conductive materials, and combinations thereof. In some embodiments, the composite current collector can be used as a hybrid current collector (current collector + anode) for Si anode batteries.

[0054] The current collectors made from composite material can be used in a wide variety of battery configurations. For example, the composite materials can be used in Li-ion batteries, anode-free batteries, Li-metal batteries, all-solid-state batteries, flow batteries, lithium-oxygen batteries, Si anode batteries, and combination thereof. In some embodiments, the battery can include, but is not limited to: one or more substrates, one or more electrolytes, one or more composite materials, and combinations thereof. For example, the composite material can stabilize the Li metal anode / electrolyte interface by an alloying approach, allowing for the use of super-164930-9759-7825 v.lPATENT Attorney Docket No. 33987-5PCT ionic conductors (solid electrolytes) that are not stable versus Li metal, by at least partially inhibiting electrolyte decomposition and Li dendrite growth.

[0055] The composite material can also be used in connection with anode free-solid-state battery (AF-SSB) technology and Si anode batteries. These technologies can mitigate safety concerns and provide a higher energy density compared to Li-ion and solid-state batteries. For the anode-free configuration, the cell can include a positive electrode (cathode) and electrolyte (liquid or solid) and a current collector and the negative electrode (Li metal) formed in-situ while the cell is cycled. However, two known issues face AF-SSBs, one is achieving a homogeneous Li deposition onto the current collector, and second is the formation of a stable solid electrolyte interface. In some embodiments, the composite material can allow for Li deposition at the Cu / electrolyte interface while maintaining its thickness during cycling, indicating its crucial role in both dendrite protection and volume stability in an anode free cell configuration. In some embodiments, the composite material can mitigate anode expansion.

[0056] The battery cell that includes a composite material can have a coulombic efficiency that varies widely. For example, a battery cell with a current collector made with the composite material can have a coulombic efficiency from a low of about 60%, to a high of about 80.0%, about 95.0%, or about 99.9%, when compared to a battery cell that has a conventional current collector In another example, a battery cell with a current collector made with the composite material can have a coulombic efficiency from a about 60.0% to about 70.0%, about 70.0% to about 80.0%, about 80.0% to about 90.0%, about 95.0% to about 99.0%, or about 90.0% to about 99.9.

[0057] The battery cell that includes a current collector made of composite materials can have a current density that varies widely. For example, a battery cell with a composite material can have a current density from a low of about 1.0 pA / cm2, about 5.0 pA / cm2, or about 10.0 pA / cm2, to a high of about 0.1 mA / cm2, about 0.2 mA / cm2, or about 25 mA / cm2. In another example, a battery cell with a current collector made of composite materials can have a current density from about 0.1 pA / cm2to about 1.0 pA / cm2, about 0.1 pA / cm2to about 1.0 mA / cm2, about 0.2 pA / cm2to about 0.5 pA / cm2, about 0.4 pA / cm2to about 0.8 pA / cm2, about 0.5 pA / cm2to about 5.0 pA / cm2, or about 0.2 mA / cm2to about 0.5 mA / cm2.EXAMPLES174930-9759-7825 v.lPATENT Attorney Docket No. 33987-5PCT

[0058] To provide a better understanding of the foregoing discussion, the following nonlimiting examples are offered. Although the examples can be directed to specific embodiments, they are not to be viewed as limiting the invention in any specific respect.

[0059] Composite materials that included a copper substate with 1 wt%, 2 wt%, and 5 wt% of Ag nanoparticles of 10 nm were made. FIGURES 1-3 shows the performance of conventional current collectors made of copper foil, and thus it does that not include the composite materials. Thermal treatments of the composite current collectors were performed on the composite current collectors made using the composite materials at 800 °C for 1 hour with a 126-minute cooling and heating time under an Ar environment. FIGURES 4-9 show experimental results for the development and performance of composite current collectors. Li was firstly uniformly deposited on the crests of the 3D Cu flowed by deposition on the troughs of the 3D. The Cu-Ag ink created structures that guided Li deposition.

[0060] The composite materials were tested in a (NMC622-Liquid electrolyte (Gen2)-Li-Composite 3D-Ag CC). The composite material showed a high and stable coulombic efficiency over 95% even after 500 cycles in a half cell configuration (composite 3D-Ag CC-electrolyte-Li), and a promising specific capacity (>140 mAh / g) in the case of the Li metal battery configuration. The results from both cell configurations - namely the observed small increase in the impedance after >100 cycles in the anode free configuration- show that the composite material forms a stable interface with Li metal and Cu current collector, in accordance with the data presented in the halfcell configuration. FIGURE 6 shows half-cells that include 3D-Ag-Electrolyte(Gen2)-Li after plating and cycling. FIGURE 11 presents graphs of specific capacity versus voltage for cells that include the NMC622 -Liquid electrolyte (Gen2)-Li-3D-Ag-Composite CC cells.

[0061] T he composite materials can serve as a protective layer by an alloying approach for improving the performance of anode-free solid-state batteries. The composite CC guides Li deposition and growth, improving the performance of anode-free Li-metal batteries or anode-free solid-state batteries. The composite material can suppress Li-dendrite formation due to its ability to guide and direct Li deposition onto the CC, leading to homogeneous Li growth.

[0062] One of ordinary skill in the art will readily appreciate that alternate but functionally equivalent components, materials, designs, and equipment may be used. The inclusion of additional elements may be deemed readily apparent and obvious to one of ordinary skill in the art. Specific elements disclosed herein are not to be interpreted as limiting, but rather as a basis184930-9759-7825 v.lPATENT Attorney Docket No. 33987-5PCT for the claims and as a representative basis for teaching one of ordinary skill in the art to employ the present invention.

[0063] Various terms have been defined above. To the extent a term used in a claim is not defined above, it should be given the broadest definition persons in the pertinent art have given that term as reflected in at least one printed publication or issued patent. Furthermore, all patents, test procedures, and other documents cited in this application are fully incorporated by reference to the extent such disclosure is not inconsistent with this application.

[0064] Certain embodiments and features have been described using a set of numerical upper limits and a set of numerical lower limits. It should be appreciated that ranges including the combination of any two values, e.g., the combination of any lower value with any upper value, the combination of any two lower values, and / or the combination of any two upper values are contemplated unless otherwise indicated. It should also be appreciated that the numerical limits may be the values from the examples. Certain lower limits, upper limits and ranges appear in at least one claims below. All numerical values are "about" or "approximately" the indicated value, and consider experimental error and variations that would be expected by a person having ordinary skill in the art.194930-9759-7825 v.l

Claims

PATENT Attorney Docket No. 33987-5PCT CLAIMSWhat is claimed is:

1. A method for making a current collector, the method comprising:mixing first metal particles, a second metal particles, and a carrier fluid to make an ink, wherein the first metal particles are selected from silicon, zirconium, magnesium, silver, gold, platinum, indium, wherein the first metal particles have an average cross-sectional diameter from about 3 nm to about 100 nm, wherein the second metal particle is selected from copper, aluminum, nickel, titanium, and steel, wherein the second metal particles have an average cross-sectional diameter from about 5 pm to about 50 pm, and wherein the carrier fluid is selected from water, toluene, ethanol, isopropanol, acetone, and hexane, N-methyl-2-pyrrolidone, acetonitrile, dimethyl sulfoxide, dimethylformamide, tetrahydrofuran, and N,N-dimethylformamide;printing, by direct ink writing, one or more layers of the ink on one or more substrates using a printing nozzle to make a current collector.

2. The method for making the current collector of claim 1, wherein the carrier fluid further comprises one or more surfactants.

3. The method for making the current collector of claim 1, wherein the one or more substrates comprise copper foil.

4. The method for making a current collector of claim 1, wherein the first metal particles and the second metal particles are combined in a weight ratio from about 0.01 to about 0.5 of the one first metal particles to the second metal particles.

5. The method for making a current collector of claim 1, wherein the ink has a viscosity from 100 Pa s to about 10 mPa s.

6. The method for making a current collector of claim 1, wherein the current collector is a three-dimensional object.

7. The method for making a current collector of claim 1, wherein the current collector is a two-dimensional planar object.

8. A method for using a current collector, the method comprising:providing a current collector, wherein the current collector is made by process comprising:mixing first metal particles, a second metal particles, and a carrier fluid to make an ink, wherein the first metal particles are selected from silicon, zirconium, magnesium, silver,204930-9759-7825 v.lPATENT Attorney Docket No. 33987-5PCT gold, platinum, indium, wherein the first metal particles have an average cross-sectional diameter from about 3 nm to about 10 nm, wherein the second metal particle is selected from copper, aluminum, nickel, titanium, and steel, wherein the second metal particles have an average cross-sectional diameter from about 5 pm to about 50 pm, and wherein the carrier fluid is selected from water, toluene, ethanol, isopropanol, acetone, and hexane, N- methyl-2-pyrrolidone, acetonitrile, dimethyl sulfoxide, dimethylformamide, tetrahydrofuran, and N,N-dimethylformamide; andprinting, by direct ink writing, one or more layers of the ink on one or more substrates using a printing nozzle to make a current collector, wherein the one or more layers comprise one or more crests and one or more troughs; andcharging the current collector, wherein the charging comprises depositing lithium on the copper substrate with one or more printed layers in the presence of sodium ions to make a copper-lithium-sodium-metal alloy on surface of the current collector.

9. The method for using a current collector of claim 8, wherein the one or more substrates comprise copper foil.

10. The method for using a current collector of claim 8, wherein the lithium is deposited on one or more crests of the one or more printed layers.

11. The method for using a current collector of claim 8, wherein the first metal particles and the second metal particles are combined in a weight ratio from about 0.01 to about 0.5 of the one first metal particles to the second metal particles.

12. The method for using a current collector of claim 8, wherein the ink has a viscosity from about 100 Pa s to about 10 mPa s.

13. The method for using a current collector of claim 8, wherein the current collector is a three-dimensional object.

14. The method for using a current collector of claim 8, wherein the one or more layers is one layer, and wherein the current collector is a two-dimensional planar object.

15. A battery cell comprising:a cathode electrode;one or more electrolytes, wherein the one or more electrolytes comprise Li ions and / or Na ions; anda current collector made by a process comprising:214930-9759-7825 v.lPATENT Attorney Docket No. 33987-5PCT combining first metal particles, a second metal particles, and a carrier fluid to make an ink, wherein the first metal particles are selected from silicon, zirconium, magnesium, silver, gold, platinum, indium, wherein the first metal particles have an average cross- sectional diameter from about 3 nm to about 10 nm, wherein the second metal particle is selected from copper, aluminum, nickel, titanium, and steel, wherein the second metal particles have an average cross-sectional diameter from about 5 pm to about 50 pm, and wherein the carrier fluid is selected from water, toluene, ethanol, isopropanol, acetone, and hexane, N-methyl-2-pyrrolidone, acetonitrile, dimethyl sulfoxide, dimethylformamide, tetrahydrofuran, and N,N-dimethylformamide; andprinting, by direct ink writing, one or more layers of the ink on a copper substrate using a printing nozzle to make a current collector.

16. The battery cell of claim 15, wherein lithium and / or sodium are deposited on the current collector to make a copper-lithium-sodium-metal alloy on surface of the current collector when the battery is charged.

17. The battery cell of claim 15, wherein the first metal particles and the second metal particles are combined in a weight ratio from about 0.01 to about 0.5 of the one first metal particles to the second metal particles.

18. The battery cell of claim 15, wherein the ink has a viscosity from about 100 Pa s to about 10 mPa s.

19. The battery cell of claim 15, wherein the current collector is a three-dimensional object.

20. The battery cell of claim 15, wherein the one or more layers is one layer, and wherein the current collector is a two-dimensional planar object.224930-9759-7825 v.l

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