Solid-state battery packs including anode electrodes with silicon-iron microparticles

Abstract

This invention includes a solid-state battery pack with an anode electrode having ferrosilicon microparticles. A solid-state battery pack includes C cathode electrodes, S separators, and A anode electrodes. The C cathode electrodes include a cathode active material layer disposed on a cathode current collector, and the A anode electrodes include an anode active material layer disposed on an anode current collector, wherein C, A, and S are integers. The anode active material layer includes ferrosilicon microparticles, which include a silicon framework and embedded ferrosilicon domains. The ferrosilicon microparticles can be produced by washing and crushing ferrosilicon ore to produce crushed ferrosilicon. The crushed ferrosilicon is ground to produce the ferrosilicon microparticles. The ferrosilicon microparticles are separated from the crushed ferrosilicon using a sieve. The ferrosilicon microparticles include a silicon framework and embedded ferrosilicon domains. The ferrosilicon microparticles are mixed with a binder. The anode electrode includes ferrosilicon microparticles and a binder.

Description

Technical Field

[0001] This disclosure relates to solid-state battery packs, and more specifically to solid-state battery packs including an anode electrode having silicon-iron microparticles. Background Technology

[0002] The information provided in this section is intended to provide a general overview of the background of this disclosure. The work of the currently named inventors described in this section, and the aspects of the specification that may not have been otherwise identified as prior art at the time of filing, are not expressly or impliedly acknowledged as prior art to this disclosure.

[0003] Electric vehicles (EVs), such as battery electric vehicles (BEVs), hybrid electric vehicles, and / or fuel cell vehicles, include one or more electric motors and a battery pack system comprising one or more battery cells, modules, and / or packs. A power control system is used to control the charging and / or discharging of the battery pack system during charging and / or driving.

[0004] The battery pack includes a cathode electrode, an anode electrode, and a separator. The cathode electrode includes a layer of cathode active material disposed on a cathode current collector. The anode electrode includes a layer of anode active material disposed on an anode current collector. Summary of the Invention

[0005] A solid-state battery pack includes C cathode electrodes, S separators, and A anode electrodes. The C cathode electrodes include a cathode active material layer disposed on a cathode current collector, and the A anode electrodes include an anode active material layer disposed on an anode current collector, wherein C, A, and S are integers. The anode active material layer includes silicon-iron microparticles comprising a silicon framework and embedded silicon-iron domains.

[0006] Among other features, the anolyte layer comprises ferrosilicon microparticles, a sulfide electrolyte, and a binder. The silicon framework has a particle size ranging from 0.3 micrometers (μm) to 10 μm. The embedded ferrosilicon domains range from 5 nanometers (nm) to 100 nm. The embedded ferrosilicon domains are selected from FeSi phase, FeSi2 phase, Fe5Si3 phase, and combinations thereof.

[0007] Among other characteristics, the capacity of anode electrode A is greater than 1500 mAh / g. The ferrosilicon particles have a silicon:iron:X composition, wherein silicon (Si) is 50% to 98% by weight, iron (Fe) is 2% to 50% by weight, and X comprises 0% to 5% by weight of one or more materials. X comprises 0.3% to 5% by weight of one or more materials selected from boron (B), aluminum (Al), calcium (Ca), nickel (Ni), copper (Cu), manganese (Mn), and combinations thereof. X comprises 0.3% to 5% by weight of one or more materials selected from the group consisting of less than 1% boron (B), less than 2% aluminum (Al), less than 1.5% calcium (Ca), less than 0.4% nickel (Ni), less than 0.4% copper (Cu), and less than 0.4% manganese (Mn).

[0008] A method for manufacturing a battery pack cell includes: washing and crushing ferrosilicon ore to produce crushed ferrosilicon; grinding the crushed ferrosilicon; separating ferrosilicon particles from the crushed ferrosilicon using a sieve, wherein the ferrosilicon particles comprise a silicon framework and embedded ferrosilicon domains; mixing the ferrosilicon particles with a binder; forming an anode electrode comprising an anode active material layer on an anode current collector, the anode active material layer comprising the ferrosilicon particles and the binder; and arranging the anode electrode in the battery pack cell.

[0009] Among other features, the battery pack further includes C cathode electrodes, S separators, and A anode electrodes. The C cathode electrodes comprise a cathode active material layer disposed on a cathode current collector, where C, A, and S are integers. The anode active material layer further comprises a sulfide electrolyte. The silicon framework has a particle size of 0.3 micrometers (μm) to 10 μm. The embedded silicon-iron domains have a size of 5 nanometers (nm) to 100 nm.

[0010] Among other characteristics, the embedded silicon-iron domains are selected from FeSi phase, FeSi2 phase, Fe5Si3 phase, and combinations thereof. The capacity of the A anode electrode is greater than 1500 mAh / g.

[0011] Among other characteristics, the ferrosilicon particles have a silicon:iron:X composition, wherein silicon (Si) is 50% to 98% by weight, iron (Fe) is 2% to 50% by weight, and X comprises 0% to 5% by weight of one or more materials. X comprises 0.3% to 5% by weight of one or more materials selected from boron (B), aluminum (Al), calcium (Ca), nickel (Ni), copper (Cu), manganese (Mn), and combinations thereof. X comprises 0.3% to 5% by weight of one or more materials selected from the group consisting of less than 1% boron (B), less than 2% aluminum (Al), less than 1.5% calcium (Ca), less than 0.4% nickel (Ni), less than 0.4% copper (Cu), and less than 0.4% manganese (Mn).

[0012] The present invention discloses the following solutions:

[0013] Option 1. A solid-state battery pack, comprising:

[0014] C cathode electrodes, each comprising a cathode active material layer disposed on a cathode current collector;

[0015] S isolation components; and

[0016] A anolyte includes an anolyte active material layer disposed on an anolyte current collector.

[0017] Where C, A, and S are integers, and

[0018] The anodic active material layer includes silicon-iron microparticles containing a silicon framework and embedded silicon-iron domains.

[0019] Option 2. The solid-state battery pack according to Option 1, wherein the anode active material layer includes silicon iron microparticles, sulfide electrolyte and binder.

[0020] Option 3. The solid-state battery pack according to Option 1, wherein the anode active material layer comprises silicon-iron microparticles and a binder.

[0021] Option 4. The solid-state battery pack according to Option 1, wherein the particle size of the silicon skeleton is from 0.3 micrometers (μm) to 10 μm.

[0022] Option 5. The solid-state battery pack according to Option 1, wherein the embedded silicon-iron domains are 5 nanometers (nm) to 100 nm.

[0023] Option 6. The solid-state battery pack according to Option 1, wherein the embedded silicon-iron domains are selected from FeSi phase, FeSi2 phase, Fe5Si3 phase and combinations thereof.

[0024] Option 7. The solid-state battery pack according to Option 1, wherein the capacity of A anode electrodes is greater than 1500 mAh / g.

[0025] Option 8. The solid-state battery pack according to Option 1, wherein the silicon-iron microparticles have a silicon:iron:X composition, wherein silicon (Si) is 50% to 98% by weight, iron (Fe) is 2% to 50% by weight, and X comprises 0% to 5% by weight of one or more materials.

[0026] Option 9. The solid-state battery pack according to Option 8, wherein X comprises 0.3% to 5% by weight of one or more materials, and is selected from boron (B), aluminum (Al), calcium (Ca), nickel (Ni), copper (Cu), manganese (Mn) and combinations thereof.

[0027] Option 10. The solid-state battery pack according to Option 8, wherein X comprises 0.3% to 5% by weight of one or more materials, and is selected from the group consisting of: less than 1% by weight of boron (B), less than 2% by weight of aluminum (Al), less than 1.5% by weight of calcium (Ca), less than 0.4% by weight of nickel (Ni), less than 0.4% by weight of copper (Cu) and less than 0.4% by weight of manganese (Mn).

[0028] Option 11. A method for manufacturing a battery pack, comprising:

[0029] The ferrosilicon ore is cleaned and crushed to produce crushed ferrosilicon.

[0030] Grind and crush the ferrosilicon;

[0031] Using a sieve to separate ferrosilicon particles from crushed ferrosilicon, wherein the ferrosilicon particles include a silicon framework and embedded ferrosilicon domains;

[0032] Mix ferrosilicon particles with a binder;

[0033] An anode electrode comprising an anode active material layer is formed on an anode current collector, the anode active material layer comprising ferrosilicon microparticles and a binder; and

[0034] The anode electrode is placed inside the battery pack.

[0035] Option 12. The method according to Option 11, wherein the battery pack further includes C cathode electrodes, S separators and A anode electrodes, wherein the C cathode electrodes include a cathode active material layer disposed on a cathode current collector, wherein C, A and S are integers.

[0036] Option 13. The method according to Option 12, wherein the anolyte active material layer further comprises a sulfide electrolyte.

[0037] Option 14. The method according to Option 11, wherein the particle size of the silicon framework is from 0.3 micrometers (μm) to 10 μm.

[0038] Option 15. The method according to Option 11, wherein the embedded silicon-iron domains are 5 nanometers (nm) to 100 nm.

[0039] Scheme 16. The method according to Scheme 11, wherein the embedded silicon-iron domains are selected from FeSi phase, FeSi2 phase, Fe5Si3 phase and combinations thereof.

[0040] Option 17. The method according to Option 11, wherein the capacity of A anode electrodes is greater than 1500 mAh / g.

[0041] Scheme 18. The method according to Scheme 11, wherein the ferrosilicon particles have a silicon:iron:X composition, wherein silicon (Si) is 50% to 98% by weight, iron (Fe) is 2% to 50% by weight, and X comprises 0% to 5% by weight of one or more materials.

[0042] Scheme 19. The method according to Scheme 18, wherein X comprises 0.3% to 5% by weight of one or more materials, and is selected from boron (B), aluminum (Al), calcium (Ca), nickel (Ni), copper (Cu), manganese (Mn) and combinations thereof.

[0043] Option 20. The method according to Option 18, wherein X comprises 0.3% to 5% by weight of one or more materials, and is selected from the group consisting of less than 1% by weight of boron (B), less than 2% by weight of aluminum (Al), less than 1.5% by weight of calcium (Ca), less than 0.4% by weight of nickel (Ni), less than 0.4% by weight of copper (Cu) and less than 0.4% by weight of manganese (Mn).

[0044] The further applicability of this disclosure will become apparent from the detailed description, claims, and drawings. The detailed description and specific embodiments are intended to be illustrative only and are not intended to limit the scope of this disclosure. Attached Figure Description

[0045] This disclosure will be more fully understood from the detailed description and the accompanying drawings, in which:

[0046] Figure 1 This is a side cross-sectional view of an example of a solid-state battery pack according to the present disclosure, which includes C cathode electrodes, S separators and A anode electrodes containing silicon-iron particles;

[0047] Figure 2AThis is a side cross-sectional view of an example of one of the C cathode electrodes, one of the A anode electrodes containing silicon-iron particles, and one of the S separators in a solid-state battery pack according to the present disclosure.

[0048] Figure 2B and Figure 2C This is a side cross-sectional view of an example of one of the A anode electrodes according to the present disclosure;

[0049] Figure 3A This is a side cross-sectional view of an example of one of the C cathode electrodes, one of the A anode electrodes containing silicon-iron particles, and one of the S separators in a solid-state battery pack according to the present disclosure.

[0050] Figure 3B and 3C This is a side cross-sectional view of an example of one of the A anode electrodes according to the present disclosure;

[0051] Figure 4 This is a flowchart of a method for manufacturing ferrosilicon particles according to the present disclosure;

[0052] Figure 5 It is shown in Figure 4 The diagram shows an example of ferrosilicon composition before and after the method described in the text.

[0053] Figure 6 This is a diagram illustrating the voltage and capacity of an example solid-state battery pack comprising an anode electrode having pure silicon and silicon-iron microparticles, respectively, during the first cycle at 0.1C and room temperature;

[0054] Figure 7 The figures illustrate examples of solid-state battery packs comprising anode electrodes with pure silicon and ferrosilicon microparticles, respectively, during cycling at 0.5C and room temperature; and

[0055] Figure 8 This is a diagram illustrating the cycle performance of an example of a solid-state battery pack comprising an anode electrode having pure silicon and ferrosilicon particles, respectively, at room temperature.

[0056] In the accompanying drawings, reference numerals may be reused to designate similar and / or identical elements. Detailed Implementation

[0057] Although this article describes solid-state battery packs in the context of vehicles, solid-state battery packs can be used in other applications, including mobile and / or stationary applications.

[0058] Silicon (Si) has emerged as a promising alternative to graphite-based anode electrodes due to its environmental friendliness and reasonable electrochemical potential (~0.3V vs. Li / Li). + ) and high theoretical capacity (for Li4.4 Si has a capacity of 4200 mAh / g. However, the Si anode electrode undergoes significant volume expansion during charging. Furthermore, nanoscale battery-grade silicon with a purity greater than 99% (2N) or 99.9% (3N) is expensive. Nanoscale silicon particles may also be coated with carbon. When using carbonate-based electrolytes, the battery pack's cycle life is adversely affected.

[0059] This disclosure relates to an all-solid-state battery pack comprising an anode electrode containing an anode active material layer incorporating silicon-iron microparticles. The silicon-iron microparticles include nano-sized Fe... y Si x Silicon framework of domains.

[0060] Ferrosilicon microparticles are prepared using relatively low-cost ferrosilicon ore as raw material. Different grades of ferrosilicon ore are currently available, with silicon content ranging from 10% to 98% by weight. Ferrosilicon ore with a predetermined silicon concentration greater than 50% by weight is selected. The ferrosilicon ore is crushed and ground to reduce its size to microparticles. Material separation (e.g., sieves or screens) is used to remove excessively large particles.

[0061] Ferrosilicon microparticles are used as the anode active material layer in lithium-ion battery packs. In some instances involving solid electrolytes, ferrosilicon microparticles form a robust solid-electrolyte interface (SEI) with the solid electrolyte to achieve stable battery cycling. y Si x Domains provide higher electronic conductivity and at least partially mitigate silicon expansion that occurs during cycling.

[0062] Now for reference Figure 1 The solid-state battery pack 10 includes C cathode electrodes 20, A anode electrodes 40, and S separators 32 arranged in a predetermined order within the battery pack stack 12, where C, S, and A are integers greater than zero. In some instances, the vehicle 11 includes a battery pack module or battery pack 13 that includes the battery pack 10. The battery pack stack 12 is arranged within a housing 50.

[0063] C cathode electrodes 20-1, 20-2, ..., and 20-C include a cathode active material layer 24 disposed on one or both sides of the cathode current collector 26. A anode electrodes 40-1, 40-2, ..., and 40-A include an anode active material layer 42 disposed on one or both sides of the anode current collector 46. The anode active material layer 42 includes silicon-iron particles.

[0064] During charging / discharging, A anode electrodes 40 exchange lithium ions with C cathode electrodes 20. In some instances, the cathode active material layer 24 and / or the anode active material layer 44 include a coating applied to the current collector, the coating comprising one or more active materials, a solid electrolyte, one or more conductive additives, and / or one or more binder materials.

[0065] In some instances, the anode current collector 46 and / or the cathode current collector 26 comprises metal foil, metal mesh, perforated metal, 3D metal foam, and / or expanded metal. External tabs 28 and 48 are connected to the current collectors of the cathode and anode electrodes, respectively, and can be arranged on the same or different sides of the battery pack stack 12. External tabs 28 and 48 are connected to the terminals of the battery cells in the battery pack.

[0066] Now for reference Figures 2A to 2C This illustrates an example of a solid-state battery and one of the A anode electrodes of the solid-state battery. Figure 2A In the C cathode electrodes 20, the cathode active material layer 24 includes a cathode active material 62 and a solid electrolyte 64. In some examples, the solid electrolyte 64 includes a sulfide-based solid electrolyte (e.g., lithium silicon phosphorus sulfide chloride (LiSiPSCl)). The anodic active material layer 44 of one of the A anode electrodes 40 is shown prior to formation as including an anodic active material comprising ferrosilicon microparticles 72 (including a silicon framework 73 and ferrosilicon Fe). y Si x 75) and solid electrolyte 74. In Figure 2B The image shows the anode electrode 40 in a discharged state after its formation. The anode active material layer 44 includes lithium silicon 76 and ferrosilicon Fe. y Si x Domain 75, solid electrolyte 74, and binder 78. Figure 2C The image shows the anode electrode 40 in a charged state after its formation. Vertical voids 77 are formed in the anode active material layer 44.

[0067] Now for reference Figures 3A to 3C The anode active material layer 44 is shown to include an anode active material comprising ferrosilicon microparticles 72 (including a silicon framework 73 and ferrosilicon Fe). y Si x Domain 75) and adhesive 78. In Figure 3B The image shows the anode electrode 40 in a discharged state after its formation. The anode active material layer 44 includes lithium silicon 76 and ferrosilicon Fe. y Si x Domain 75 and adhesive 79. In Figure 3CThe image shows the anode electrode 40 in a charged state after its formation. Vertical voids 81 are formed in the anode active material layer 44.

[0068] In some instances, the ferrosilicon particles 72 have a silicon:iron:X composition, wherein silicon (Si) is 50% to 98% by weight, iron (Fe) is 2% to 50% by weight, and X is 0% to 0% by weight. In some instances, X comprises one or more materials selected from boron (B), aluminum (Al), calcium (Ca), nickel (Ni), copper (Cu), manganese (Mn), and combinations thereof. In some instances, boron (B) accounts for less than 1% by weight, aluminum (Al) accounts for less than 2% by weight, calcium (Ca) accounts for less than 1.5% by weight, nickel (Ni) accounts for less than 0.4% by weight, copper (Cu) accounts for less than 0.4% by weight, and manganese (Mn) accounts for less than 0.4% by weight.

[0069] In some instances, Fe y Si x Domains include FeSi phase, FeSi2 phase, Fe5Si3 phase, and / or combinations thereof. In some examples, the silicon framework has a grain size of 0.3 μm to 10 μm (e.g., 6 μm). In some examples, Fe... y Si x The domain size ranges from 5 nm to 100 nm. In some instances, the anode capacity is greater than 1500 mAh / g.

[0070] In some instances, ferrosilicon microparticles are mixed with a sulfide solid electrolyte and a binder (with or without a solvent) to form an anolyte active material layer.

[0071] For example, SiFe7525 is a commonly used deoxidizer and alloying additive (e.g., in the metallurgical industry) with a particle size greater than 100 μm. In some instances, ferrosilicon microparticles produced using SiFe7525, after ball milling in ethanol at 500 rpm for 1 hour with a ball-to-material ratio of 20:1, have a particle size of 6 to 7 μm. (See now for reference.) Figure 5 Due to the reduced particle size, ball milling leads to a decrease in peak intensity and a broadening of the silicon peak (from 130°C before ball milling to 134°C after ball milling). In this example, the silicon-iron particles comprise a Si phase or Si framework and an FeSi2 phase.

[0072] Now for reference Figures 6 to 8 The electrochemical performance of a first battery pack at 220 nm was compared with that of a second battery pack at 224 nm. The first battery pack consisted of pure Si-3N (or 99.9% purity), and the second battery pack consisted of 70:30 mass ratio silicon-iron particles (containing 75% silicon by weight) and a sulfide electrolyte. Figure 6and Figure 7 In the first battery pack 220 and the second battery pack 224, the initial cycle performance at 0.1C and 0.5C (at room temperature (RT)) was similar. The second battery pack 224, which includes silicon-iron microparticles, exhibited slightly lower discharge capacity (130.5 vs 132.4 mAh / g) and coulombic efficiency (76.6% vs 78.6%), and slightly higher rate performance (88.7% vs 86.4% at 0.5C / 0.1C). Figure 8 The image shows the capacity retention of the first battery pack 220 and the second battery pack 224. The second battery pack 224 shows an improved capacity retention.

[0073] The foregoing description is merely exemplary and is in no way intended to limit this disclosure, its application, or its use. The broad teachings of this disclosure can be implemented in various forms. Therefore, although this disclosure includes specific examples, its true scope should not be limited thereto, as other modifications will become apparent upon examination of the drawings, specification, and the following claims. It should be understood that one or more steps within the method may be performed in a different order (or simultaneously) without altering the principles of this disclosure. Furthermore, although the embodiments are described above as having certain features, any one or more features described with respect to any embodiment of this disclosure may be implemented in any other embodiment and / or combined with features of any other embodiment, even if such combination is not explicitly described. In other words, the embodiments are not mutually exclusive, and substitution of one or more embodiments for each other remains within the scope of this disclosure.

Claims

1. A solid-state battery pack, comprising: C cathode electrodes, each comprising a cathode active material layer disposed on a cathode current collector; S isolation components; and A anolyte includes an anolyte active material layer disposed on an anolyte current collector. Where C, A, and S are integers, and The anodic active material layer includes silicon-iron microparticles containing a silicon framework and embedded silicon-iron domains.

2. The solid-state battery pack according to claim 1, wherein the anode active material layer comprises silicon iron microparticles, sulfide electrolyte, and binder.

3. The solid-state battery pack according to claim 1, wherein the anode active material layer comprises silicon-iron microparticles and a binder.

4. The solid-state battery pack according to claim 1, wherein the particle size of the silicon skeleton is from 0.3 micrometers (μm) to 10 μm.

5. The solid-state battery pack according to claim 1, wherein the embedded silicon-iron domains are 5 nanometers (nm) to 100 nm.

6. The solid-state battery pack according to claim 1, wherein the embedded silicon-iron domains are selected from FeSi phase, FeSi2 phase, Fe5Si3 phase and combinations thereof.

7. The solid-state battery pack according to claim 1, wherein the capacity of A anode electrodes is greater than 1500 mAh / g.

8. The solid-state battery pack according to claim 1, wherein the silicon-iron microparticles have a silicon:iron:X composition, wherein silicon (Si) is 50% to 98% by weight, iron (Fe) is 2% to 50% by weight, and X comprises 0% to 5% by weight of one or more materials.

9. The solid-state battery pack according to claim 8, wherein X comprises 0.3% to 5% by weight of one or more materials, and is selected from boron (B), aluminum (Al), calcium (Ca), nickel (Ni), copper (Cu), manganese (Mn) and combinations thereof.

10. The solid-state battery pack according to claim 8, wherein X comprises 0.3% to 5% by weight of one or more materials, and is selected from the group consisting of less than 1% by weight of boron (B), less than 2% by weight of aluminum (Al), less than 1.5% by weight of calcium (Ca), less than 0.4% by weight of nickel (Ni), less than 0.4% by weight of copper (Cu) and less than 0.4% by weight of manganese (Mn).

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