Alloy coating on lithium metal anode with nitrogen-rich solid electrolyte interface

Abstract

The invention discloses an alloy coating on a lithium metal anode having a nitrogen-rich solid electrolyte interface. A battery cell includes: a cell stack including A anode electrodes including an anode active material layer disposed adjacent to an anode current collector; c cathode electrodes comprising a cathode active material layer arranged adjacent to the cathode current collector; and S separators disposed between the A anode electrodes and the C cathode electrodes. The anode active material layer of the A number of anode electrodes includes a lithium metal layer and a lithium alloy layer comprising an alloy of lithium and a lithium-philic metal.

Description

Technical Field

[0001] The present disclosure relates to lithium metal anode (LMA) electrodes for battery cells. Background Art

[0002] The information provided in this section is for the purpose of generally presenting the background of the present disclosure. The work of the presently named inventors, to the extent described in this section and in all aspects of the description that might not otherwise constitute prior art at the time of filing, is neither expressly nor impliedly admitted as prior art to the present disclosure.

[0003] The present disclosure relates to lithium metal anode (LMA) electrodes for battery cells.

[0004] Electric vehicles (EVs), such as battery electric vehicles (BEVs), hybrid vehicles, and / or fuel cell vehicles, include one or more motors and a battery system, wherein the battery system includes one or more battery cells, battery modules, and / or battery packs. A battery control module is used to control the charging and / or discharging of the battery system during charging and / or driving. EV manufacturers are pursuing increased power density to increase the range of EVs. Summary of the invention

[0005] A battery cell includes: a battery cell stack, the battery cell stack including: A anode electrodes including an anode active material layer arranged adjacent to an anode current collector; C cathode electrodes including a cathode active material layer arranged adjacent to a cathode current collector; and S separators arranged between the A anode electrodes and the C cathode electrodes. The anode active material layer of the A anode electrodes includes a lithium metal layer and a lithium alloy layer, the lithium alloy layer including an alloy of lithium and a lithium-philic metal.

[0006] In other features, the lithium-philic metal is selected from zinc, indium, tin, aluminum, silver and gallium. A lithium nitrate layer is disposed on the lithium alloy layer. A housing surrounds the battery cell stack, and a liquid electrolyte is disposed in the housing.

[0007] In other features, the battery cell stack includes a solid electrolyte. The lithium metal layer is disposed on opposite sides of an anode current collector. The anode current collector is made of a material selected from copper, stainless steel, and nickel. The anode current collector and the lithium metal layer include a laminated foil.

[0008] A method for manufacturing a battery cell includes: providing a lithium metal anode electrode, the lithium metal anode electrode including a first lithium metal layer and a second lithium metal layer disposed on opposite sides of an anode current collector; and immersing the first lithium metal layer and the second lithium metal layer and the anode current collector in a bath containing a metal salt solution, the metal salt solution containing a lithium-philic metal and a nitrate. The lithium metal anode electrode is coated with a lithium alloy layer and a lithium nitrate layer.

[0009] In other features, the method includes selecting the lithium-philic metal from zinc, indium, tin, aluminum, silver, and gallium. The method includes forming a battery cell stack, the battery cell stack including: A anode electrodes of the lithium metal; C cathode electrodes including a cathode active material layer disposed adjacent to a cathode current collector; and S separators disposed between the A anode electrodes and the C cathode electrodes.

[0010] In other features, the method includes removing the lithium nitrate layer. The method includes using a solid electrolyte.

[0011] In other features, the method includes arranging the battery cell stack in a housing and using a liquid electrolyte. The anode current collector is made of a material selected from copper, stainless steel, and nickel. The anode current collector and the first and second lithium metal layers include a laminate foil.

[0012] A method for manufacturing a battery cell, comprising: providing a lithium metal anode electrode, the lithium metal anode electrode comprising a laminate foil, the laminate foil comprising a first lithium metal layer and a second lithium metal layer arranged on opposite sides of an anode current collector; and immersing the laminate foil in a bath containing a metal salt solution for a predetermined period of time, the metal salt solution containing a lithium-loving metal and a nitrate. The lithium-loving metal is selected from zinc, indium, tin, aluminum, silver and gallium. The outer surfaces of the first lithium metal layer and the second lithium metal layer of the laminate foil are coated with a lithium-metal alloy layer and a lithium nitrate layer.

[0013] In other features, the method includes: forming a battery cell stack, the battery cell stack comprising: A lithium metal anode electrodes; C cathode electrodes, which include a cathode active material layer arranged adjacent to the cathode current collector; and S separators arranged between the A anode electrodes and the C cathode electrodes.

[0014] In other features, the method includes removing the lithium nitrate layer and using a solid electrolyte.

[0015] In other features, the method includes arranging a battery cell stack in a housing and using a liquid electrolyte.

[0016] The present invention discloses the following embodiments:

[0017] 1. A battery cell, comprising:

[0018] A battery cell stack comprising:

[0019] A anode electrode including an anode active material layer disposed adjacent to an anode current collector;

[0020] C cathode electrodes including a cathode active material layer disposed adjacent to a cathode current collector; and

[0021] S separators are arranged between the A anode electrodes and the C cathode electrodes,

[0022] The anode active material layer of the A anode electrodes comprises:

[0023] a lithium metal layer; and

[0024] The lithium alloy layer comprises an alloy of lithium and a lithium-philic metal.

[0025] 2. The battery cell of claim 1 , wherein the lithium-philic metal is selected from zinc, indium, tin, aluminum, silver and gallium.

[0026] 3. The battery cell according to Option 1 further includes a lithium nitrate layer arranged on the lithium alloy layer.

[0027] 4. The battery cell according to solution 2 further comprises:

[0028] a housing surrounding the battery cell stack; and

[0029] A liquid electrolyte is within the housing.

[0030] 5. A battery cell according to Option 1, wherein the battery cell stack also includes a solid electrolyte.

[0031] 6. The battery cell according to Option 1, wherein the lithium metal layer is arranged on opposite sides of the anode current collector.

[0032] 7. The battery cell according to Option 6, wherein the anode current collector is made of a material selected from the group consisting of copper, stainless steel and nickel.

[0033] 8. The battery cell of Option 6, wherein the anode current collector and the lithium metal layer comprise laminated foils.

[0034] 9. A method for manufacturing a battery cell, comprising:

[0035] providing a lithium metal anode electrode comprising a first lithium metal layer and a second lithium metal layer disposed on opposite sides of an anode current collector; and

[0036] immersing the first and second lithium metal layers and the anode current collector in a bath containing a metal salt solution containing a lithium-philic metal and a nitrate,

[0037] The lithium metal anode electrode is coated with a lithium alloy layer and a lithium nitrate layer.

[0038] 10. The method according to Option 9 also includes selecting the lithium-philic metal from zinc, indium, tin, aluminum, silver and gallium.

[0039] 11. The method according to claim 10, further comprising forming a battery cell stack, the battery cell stack comprising:

[0040] A lithium metal anode electrode;

[0041] C cathode electrodes including a cathode active material layer disposed adjacent to a cathode current collector; and

[0042] S separators are arranged between the A anode electrodes and the C cathode electrodes.

[0043] 12. The method according to Scheme 10 further comprises removing the lithium nitrate layer.

[0044] 13. A method according to Option 12, wherein the battery cell stack includes a solid electrolyte.

[0045] 14. The method according to claim 11 further includes arranging the battery cell stack in a housing and using a liquid electrolyte.

[0046] 15. The method according to Option 9, wherein the anode current collector is made of a material selected from the group consisting of copper, stainless steel and nickel.

[0047] 16. The method of claim 15, wherein the anode current collector and the first and second lithium metal layers comprise laminated foils.

[0048] 17. A method for manufacturing a battery cell, comprising:

[0049] providing a lithium metal anode electrode comprising a laminate foil including a first lithium metal layer and a second lithium metal layer disposed on opposite sides of an anode current collector; and

[0050] immersing the laminated foil in a bath containing a metal salt solution containing a lithiophilic metal and a nitrate for a predetermined period of time,

[0051] wherein the lithium-philic metal is selected from zinc, indium, tin, aluminum, silver and gallium, and

[0052] The outer surfaces of the first lithium metal layer and the second lithium metal layer of the laminated foil are coated with a lithium-metal alloy layer and a lithium nitrate layer.

[0053] 18. The method according to claim 17, further comprising forming a battery cell stack, the battery cell stack comprising:

[0054] A lithium metal anode electrode;

[0055] C cathode electrodes including a cathode active material layer disposed adjacent to a cathode current collector; and

[0056] S separators are arranged between the A anode electrodes and the C cathode electrodes.

[0057] 19. The method according to claim 17, further comprising:

[0058] removing the lithium nitrate layer; and

[0059] Use a solid electrolyte.

[0060] 20. The method according to claim 18 further includes arranging the battery cell stack in a housing and using a liquid electrolyte.

[0061] Further areas of applicability of the present disclosure will become apparent from the detailed description, claims and drawings.The detailed description and specific examples are intended for illustrative purposes only and are not intended to limit the scope of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] The present disclosure will be more fully understood from the detailed description and accompanying drawings, in which:

[0063] Figure 1 is a side cross-sectional view of an example of a battery cell including a lithium metal anode (LMA) electrode having a lithium-metal alloy coating according to the present disclosure;

[0064] Figure 2 is a side cross-sectional view of an example of a plurality of battery cells arranged in a housing of a battery pack;

[0065] Figure 3 and 4 An example of coating an LMA electrode with a lithium metal layer and a lithium nitrate layer according to the present disclosure is shown;

[0066] Figure 5 is a flow chart of an example of a method for manufacturing a battery cell according to the present disclosure, the method forming a battery cell by coating an LMA electrode and combining an anode electrode with a cathode electrode and a separator; and

[0067] Figure 6An example of electrochemical deposition of a lithium alloy layer onto a LMA electrode is shown.

[0068] Among the drawings, reference numerals may be repeated to identify similar and / or identical elements. DETAILED DESCRIPTION

[0069] Although the battery cell having a lithium metal anode (LMA) electrode including a lithium-metal alloy coating according to the present disclosure is described in conjunction with an electric vehicle, the battery cell having a lithium metal anode (LMA) electrode including a lithium-metal alloy coating may be used in other applications.

[0070] Corrosion of lithium metal in LMA electrodes may occur in a battery cell. When corrosion occurs, it consumes lithium and / or electrolyte and results in a reduction in the capacity of the lithium metal battery (LMB). Lithium also has poor wettability for most solid state electrolytes (SSEs).

[0071] The present disclosure relates to modifying the surface of a lithium metal anode (LMA) electrode with a lithium-metal alloy to mitigate lithium dendrite growth and minimize corrosion of the lithium of the LMA. The coating also improves wettability of the plated lithium during charging.

[0072] In some examples, the LMA electrode is immersed in a solution containing lithium-philic metal ions M + The lithium surface is also coated with lithium nitrate (LiNO 3 ). For applications using liquid electrolytes, LiNO 3 The layer increases the high ionic conductivity of nitrogen-based electrolytes for lithium (such as Li 3 For applications using solid electrolytes (SSE), lithium nitrate (LiNO) can be rinsed / removed using ether-based electrolytes or other suitable electrolytes. 3 ).

[0073] Reference now Figure 1 and 2, the battery cell 10 includes cathode electrodes 20-1, 20-2, ..., and 20-C, where C is an integer greater than one. The cathode electrode 20 includes a cathode active material layer 24 arranged on one side or both sides of the cathode current collector 26. The battery cell 10 includes anode electrodes 40-1, 40-2, ..., and 40-A, where A is an integer greater than one. The anode electrode 40 includes an anode active material layer 42 containing lithium metal arranged on one side or both sides of the anode current collector 46. The cathode electrode 20, the anode electrode 40, and the separator 32 are arranged in a predetermined order in the housing 50. For example, the separator 32 is arranged between the cathode electrode 20 and the anode electrode 40.

[0074] exist Figure 2 , the battery pack 58 includes M battery modules 56 - 1 , 56 - 2 , . . . , and 56 -M, each battery module including B battery cells 10 (e.g., battery cells 10 - 1 , 10 - 2 , . . . , and 10 -B), where B and M are integers greater than 1. The housing 60 includes a cover 62 and a lower portion or tray 64 .

[0075] Reference now Figure 3 and 4 The lithium metal anode layer 110 is immersed in a solution containing metal ions (M + )118 and nitrate (NO 3 - ) 112. A lithium-metal (lithium-M) alloy layer 130 is formed on the surface of the lithium metal anode layer 110 by electrochemical deposition. A lithium nitrate layer 134 is also formed on the lithium-M alloy layer 130.

[0076] In some instances, the lithium metal anode layer 110 is arranged on both sides of the anode current collector 140, and is plated on the external exposed surface of the lithium metal anode layer 110. In some instances, the lithium-M alloy layer 130 has a thickness in the range of 20nm to 100nm. In some instances, the thickness of the lithium-M alloy layer 130 depends on the electrochemical deposition time period and the concentration of metal ions in the metal salt. In some instances, (one or more) lithium metal anode layers 110 and the current collector include laminated foils. In some instances, the anode current collector is made of a material selected from copper, stainless steel or nickel.

[0077] When LMA is immersed in metal salt, the surface of LMA and the lithium-philic metal ions M + In some embodiments, the metal ion M + Including zinc ions (Zn 2+ ), indium ions (In 3+ ), tin ions (Sn 2+), aluminum ions (Al 3+ ), silver ion Ag + 、Gallium ion Ga 3+ and / or other suitable lithiophilic metal ions. Lithium has a very low redox potential (-3.04 V vs. normal hydrogen electrode) and undergoes oxidation, releasing electrons e when placed in a salt solution of the target metal (M) ion. - To reduce the metal ions on the lithium surface.

[0078] The reduced metal reacts with the lithium surface to form a lithium-metal (Li-M) alloy. When the nitrate of the target lithiophilic element is used, the lithium surface is enriched with lithium nitrate (LiNO 3 ). LiNO 3 The addition of nitrogen-based electrolyte species with high ionic conductivity for lithium (such as Li 3 N) solid electrolyte interface (SEI). This will lead to the deposition of planar lithium and increase the cycle life of lithium metal batteries (LMB). The following reaction outlines the galvanic replacement process:

[0079] xLi+M(NO 3 )x=M+xLiNO 3

[0080] yLi+zM=Li y M z

[0081] Reference now Figure 5 , a method for manufacturing a battery cell including a metal-coated lithium metal anode is shown. At 210, the lithium metal anode is immersed in a liquid containing metal ions M + In a metal salt solution, a lithium metal (LiM) alloy layer is formed on the lithium metal anode and a lithium nitrate (LiNO) is formed on the LiM alloy layer. 3 )layer.

[0082] At 214, for applications using a solid electrolyte with high wettability to LMA, the surface is optionally rinsed with an ether-based electrolyte to remove surface LiNO 3 In some instances, for applications using liquid electrolytes, the surface LiNO is not rinsed / removed. 3 layer (e.g., surface LiNO 3 At 218, a battery cell is fabricated using a lithium metal anode, a cathode electrode, and a separator.

[0083] Reference now Figure 6, shows an example of a method for coating a lithium metal anode electrode 520. The lithium metal anode electrode 520 is immersed in a bath 510 containing a metal salt 514 containing a lithium-philic metal ion for a predetermined period of time. A power source 522 is connected to the lithium metal anode electrode 520 and the metal salt 514 or the outer shell of the bath 510 (if conductive). + In some embodiments, the metal ion M + Including zinc ions (Zn 2+ ), indium ions (In 3+ ), tin ions (Sn 2+ ), aluminum ions (Al 3+ ), silver ion Ag + 、Gallium ion Ga 3+ and / or other suitable metal ions.

[0084] The present disclosure provides a low-cost method for coating the surface of LMA with a thin layer of a lithium-metal alloy of a lithium-philic metal to mitigate lithium dendrite growth and increase the wettability and particle size of the plated lithium. The lithium-M alloy layer is used as a protective coating to minimize galvanic corrosion of the LMA. The method also enriches the SEI layer with nitrogen-based species to provide uniform lithium ion flux through the SEI and increase the size of the plated lithium during charging. The method also improves the wettability of the lithium anode with the SSE.

[0085] The foregoing description is essentially only illustrative, and is by no means intended to limit the present disclosure, its application or use. The broad teachings of the present disclosure can be implemented in various forms. Therefore, although the present disclosure includes specific examples, the true scope of the present disclosure should not be limited thereto, because after studying the drawings, the specification and the appended claims, other modifications will become apparent. It should be understood that, without changing the principles of the present disclosure, one or more steps in the method can be performed in different orders (or simultaneously). In addition, although each of the embodiments is described above as having certain features, any one or more of those features described with respect to any embodiment of the present disclosure can be implemented in any other embodiment and / or combined with the features of any other embodiment, even if the combination is not explicitly described. In other words, the embodiments described are not mutually exclusive, and the permutations and combinations of one or more embodiments are maintained within the scope of the present disclosure.

[0086] Various terms are used to describe the spatial and functional relationships between elements (e.g., between modules, circuit elements, electrode layers, semiconductor layers, etc.), including "connected," "engaged," "coupled," "adjacent," "close to," "on top of," "above," "below," and "disposed." Unless explicitly described as "directly," when describing the relationship between a first element and a second element in the above disclosure, the relationship may be a direct relationship in which no other intermediate elements exist between the first element and the second element, but may also be an indirect relationship in which one or more intermediate elements exist (spatially or functionally) between the first element and the second element. As used herein, the phrase at least one of A, B, and C should be interpreted as meaning a logic (A OR B OR C) using a non-exclusive logical OR, and should not be interpreted as meaning "at least one of A, at least one of B, and at least one of C."

[0087] In the drawings, the direction of the arrow, as indicated by the arrow portion, generally represents the flow of information (e.g., data or instructions) related to the diagram. For example, when element A and element B exchange various information, but the information transmitted from element A to element B is related to the diagram, the arrow may point from element A to element B. The unidirectional arrow does not imply that no other information is transmitted from element B to element A. In addition, for information sent from element A to element B, element B may send a request for the information or a confirmation of receipt of the information to element A.

Claims

1. A battery cell, comprising: A battery cell stack comprising: A anode electrode including an anode active material layer disposed adjacent to an anode current collector; C cathode electrodes including a cathode active material layer disposed adjacent to a cathode current collector; and S separators are arranged between the A anode electrodes and the C cathode electrodes, The anode active material layer of the A anode electrodes comprises: a lithium metal layer; and The lithium alloy layer comprises an alloy of lithium and a lithium-philic metal.

2. The battery cell of claim 1, wherein the lithium-philic metal is selected from the group consisting of zinc, indium, tin, aluminum, silver, and gallium. 3 . The battery cell according to claim 1 , further comprising a lithium nitrate layer disposed on the lithium alloy layer.

4. The battery cell according to claim 2, further comprising: a housing surrounding the battery cell stack; as well as A liquid electrolyte is within the housing. The battery cell of claim 1 , wherein the battery cell stack further comprises a solid electrolyte. 6 . The battery cell of claim 1 , wherein the lithium metal layers are disposed on opposite sides of the anode current collector. 7 . The battery cell of claim 6 , wherein the anode current collector is made of a material selected from the group consisting of copper, stainless steel, and nickel.

8. The battery cell of claim 6, wherein the anode current collector and the lithium metal layer comprise a laminated foil.

9. A method for manufacturing a battery cell, comprising: providing a lithium metal anode electrode comprising a first lithium metal layer and a second lithium metal layer disposed on opposite sides of an anode current collector; as well as immersing the first and second lithium metal layers and the anode current collector in a bath containing a metal salt solution containing a lithium-philic metal and a nitrate, The lithium metal anode electrode is coated with a lithium alloy layer and a lithium nitrate layer.

10. The method of claim 9, further comprising selecting the lithiophilic metal from zinc, indium, tin, aluminum, silver, and gallium.

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