Bipolar solid state battery cell

Abstract

The present invention relates to a bipolar solid state battery cell comprising a plurality of electrochemical cells arranged in a stack such that adjacent electrochemical cells share an electronic conductor, the plurality of stacked electrochemical cells being arranged in series, and the bipolar solid state battery cell comprising: a cathode current collector; a first electrochemical unit including a first catholyte layer, a first solid electrolyte, and a first electron conductor; x second electrochemical cells each comprising a second catholyte layer, a second solid electrolyte and a second electronic conductor, where x is 0 to 8; a third electrochemical unit including a third catholyte layer and a third solid electrolyte; an anode current collector; and an electrically insulating layer. The invention further relates to a bipolar solid state battery comprising a stack of at least two bipolar solid state battery cells.

Description

[0001] Technical Field of the Invention

[0002] The present invention relates to bipolar solid-state battery cells, and more particularly to bipolar solid-state battery cells including a plurality of stacked electrochemical cells. The present invention further relates to a bipolar solid-state battery pack including a plurality of stacked bipolar solid-state battery cells.

[0003] Background

[0004] Secondary battery packs have been known for some time. In the search for secondary battery packs with high energy density and high power output, bipolar battery packs have been developed. In particular, bipolar lithium-ion secondary battery packs (referred to simply as bipolar lithium-ion battery packs) have attracted great interest.

[0005] A bipolar battery cell includes a stack of electrochemcial cells arranged in series. To achieve such a stack, bipolar electrodes are used between an external cathode and an external anode, with electrolyte present between the cathode and an adjacent bipolar electrode, between corresponding adjacent bipolar electrodes, and between the anode and its adjacent bipolar electrode.

[0006] EP 1487034 discloses a bipolar battery pack having bipolar electrodes and electrolyte layers. The bipolar electrode includes a current collector, a positive electrode layer formed on one surface of the current collector, and a negative electrode layer formed on the other surface of the current collector. The bipolar electrodes are laminated in sequence to provide a series connection via the electrolyte layer to form a stack structure. The positive electrode layer, negative electrode layer, and electrolyte layer are potted in resin. The resin portion of the battery pack provides anti-vibration and anti-shock protection for the in-vehicle battery pack during operation, and provides waterproof, heat-resistant, airtight, and electrolyte-resistant properties for the battery pack.

[0007] Disadvantages of such bipolar battery pack components include limited power density and energy density, requiring a large stack to obtain sufficient power density. Therefore, a large amount of heat is generated during use, especially within the electrochemical cells in the middle of the stack. This heat tends to accumulate within the battery pack components, leading to electrolyte degradation (such as oxygen release), and resulting in safety risks and a limited service life of the bipolar battery pack components. Another disadvantage is that the resin portion used as the potting material provides insufficient protection in the case of overvoltage of the battery pack. In addition, if a liquid electrolyte is used, there is a risk of electrolyte leakage, which also results in safety risks.

[0008] US2009017371 discloses an electric power storage device, which includes a plurality of electrolyte layers, and electrode elements are inserted between the stacked electrolyte layers. To solve the heat dissipation problem, the plurality of electrolyte layers include an electrolyte layer disposed at a first position in the stacking direction and an electrolyte layer disposed at a second position different from the first position, such that the heat radiation at the second position is lower than that at the first position. The resistance value of the electrolyte layer at the second position is higher than that of the electrolyte layer at the first position. The electrolyte may be a solid electrolyte containing particles, wherein the particle density at the second position is lower than that at the first position.

[0009] The disadvantage of such a bipolar battery pack is the complex setting, and the electrolyte layers require different components. In addition, the power density and energy density of the bipolar battery pack are still limited, and it provides limited safety, especially during the use of the battery pack.

[0010] US2008118826 discloses a lithium-ion battery pack, and its battery elements include a cathode, an anode, and an electrolyte layer between the cathode and the anode. The electrolyte layer includes an arrangement structure of insulating particles, and there are a plurality of interstitial spaces between these insulating particles, wherein the electrolyte occupies at least part of the interstitial spaces.

[0011] US2009269665 discloses a bipolar battery pack with an inorganic solid electrolyte to provide an electric power storage device that can prevent the reduction of the energy efficiency of the electric power storage device and avoid the change of the temperature distribution.

[0012] JP2019140024 discloses a method for laminating a sulfide and an oxide-based solid electrolyte layer in a bipolar all-solid-state battery pack stack.

[0013] The disadvantage of the aforementioned bipolar battery pack is that they are prone to overcharging and / or overvoltage, thus providing limited safety. Summary of the Invention

[0014] The object of the present invention is to overcome one or more of the aforementioned disadvantages. The object of the present invention is to provide a bipolar solid-state battery pack element and a bipolar solid-state battery pack with a high power density. Another object of the present invention is to provide a bipolar solid-state battery pack element and a bipolar solid-state battery pack with improved safety compared with the bipolar solid-state battery pack elements and bipolar solid-state battery packs of the prior art.

[0015] According to a first aspect of the present invention, it provides a bipolar solid-state battery pack cell as described in the appended claims.

[0016] The bipolar solid-state battery pack cell includes a plurality of electrochemical units. The plurality of electrochemical units are arranged in a stack such that adjacent electrochemical units share an electronic conductor. Advantageously, the plurality of stacked electrochemical units are arranged in series.

[0017] The bipolar solid-state battery pack cell includes a cathode current collector. The cathode current collector can be any cathode current collector known in the art. Advantageously, the cathode current collector contains aluminum or consists essentially of aluminum.

[0018] The bipolar solid-state battery pack cell further includes a first electrochemical cell. The first electrochemical cell includes a first cathode electrolyte layer, a first solid electrolyte, and a first electronic conductor.

[0019] The first cathode electrolyte layer contains a first active material. The first active material can be any active material known in the art.

[0020] Advantageously, the first cathode electrolyte layer further contains an electronically conductive compound and / or an ionically conductive compound. The first cathode electrolyte layer can further contain a binder. The electronically conductive compound, the ionically conductive compound, and the optional binder can be known in the art.

[0021] Advantageously, the first solid electrolyte contains or consists essentially of an alkali metal, an alkaline earth metal, a transition metal, or a combination thereof. Preferred examples of alkali metals include, but are not limited to, lithium and sodium. For example, the first solid electrolyte can contain or consist essentially of Li7La3Zr2O 12 (LLZO). Preferred examples of alkaline earth metals include, but are not limited to, magnesium. Preferred examples of transition metals include, but are not limited to, aluminum.

[0022] Advantageously, the first electronic conductor contains or consists essentially of steel, a steel alloy, titanium, a titanium alloy, vitreous carbon (also a registered trademark for glassy carbon or vitreous carbon), or a combination of two or more thereof. Non-limiting examples of steel include stainless steel, carbon steel, and A36.

[0023] Optionally, the first electrochemical cell further includes a first anode layer. The first anode layer can be any anode layer known in the art. Advantageously, when present, the first anode layer contains or consists essentially of an alkali metal, an alkaline earth metal, a transition metal, graphite, silicon, a carbide, or a combination of two or more thereof.

[0024] The bipolar solid-state battery pack cell further includes x second electrochemical cells. Advantageously, x is from 0 to 20, such as from 0 to 15, preferably from 0 to 10, more preferably from 0 to 8, for example from 0 to 5, or 0 to 1. As will be understood, when x is 0, the bipolar solid-state battery pack cell includes two electrochemical cells, namely the first electrochemical cell and the third electrochemical cell, and the bipolar solid-state battery pack cell does not include any second electrochemical cells.

[0025] Each second electrochemical unit, when present (i.e., when x is from 1 to 8), respectively includes a second cathode electrolyte layer, a second solid electrolyte, and a second electronic conductor.

[0026] The second cathode electrolyte layer contains a second active material. The second active material is advantageously as described above for the first active material. Advantageously, the second cathode electrolyte layer further contains an electronically conductive compound and / or an ionically conductive compound. The second cathode electrolyte layer may further contain a binder. The electronically conductive compound, the ionically conductive compound, and the optional binder may be known in the art.

[0027] When the bipolar solid-state battery cell includes at least two second electrochemical units (i.e., x is from 2 to 8), the second electrochemical units may have the same or different (second) cathode electrolyte layers. It will be understood that the cathode electrolyte layer of each second electrochemical unit may be the same as or different from the first cathode electrolyte layer of the first electrochemical unit.

[0028] Advantageously, the second solid electrolyte is as described above for the first solid electrolyte. When the bipolar solid-state battery cell includes two or more second electrochemical units (i.e., x is from 2 to 8), the second electrochemical units may have the same or different (second) solid electrolytes. It will be understood that the solid electrolyte of each second electrochemical unit may be the same as or different from the first solid electrolyte of the first electrochemical unit.

[0029] Advantageously, the second electronic conductor is as described above for the first electronic conductor. When the bipolar solid-state battery cell includes two or more second electrochemical units (i.e., x is from 2 to 8), the second electrochemical units may have the same or different (second) electronic conductors. It will be understood that the electronic conductor of each second electrochemical unit may be the same as or different from the first electronic conductor of the first electrochemical unit.

[0030] Optionally, when a second electrochemical unit is present (i.e., when x is from 1 to 8), the second electrochemical unit may further include a second anode layer. When the solid-state battery cell includes two or more second electrochemical units (i.e., x is from 2 to 8), some or all of the second electrochemical units may include a second anode layer. Advantageously, when a second anode layer is present, each second anode layer is respectively as described above for the optional first anode layer.

[0031] When the bipolar solid-state battery cell includes two or more second electrochemical units (i.e., x is from 2 to 8), the second electrochemical units may have the same or different second anode layers. It will be understood that when x is from 1 to 8, whether one or more second electrochemical units include a second anode layer has nothing to do with whether the first electrochemical unit includes a (first) anode layer. It will also be understood that the anode layer of each second electrochemical unit may be the same as or different from the first anode layer of the first electrochemical unit (when present).

[0032] The bipolar solid-state battery cell further includes a third electrochemical unit. The third electrochemical unit includes a third cathode electrolyte layer and a third solid electrolyte.

[0033] The third cathode electrolyte layer contains a third active material. The third active material is advantageously as described above for the first active material. Advantageously, the third cathode electrolyte layer further contains an electronically conductive compound and / or an ionically conductive compound. The third cathode electrolyte layer may further contain a binder. The electronically conductive compound, the ionically conductive compound, and the optional binder may be known in the art.

[0034] Advantageously, the third solid electrolyte is as described above for the first solid electrolyte. It will be understood that the solid electrolyte of the third electrochemical unit may be the same as or different from the solid electrolyte of the first electrochemical unit, and / or when x is from 1 to 8, the same as or different from the solid electrolyte of the second electrochemical unit.

[0035] Optionally, the third electrochemical unit further includes a third anode layer. Advantageously, when present, the third anode layer is advantageously as described above for the optional first anode layer and / or the optional second anode layer. It will be understood that when present, the anode layer of the third electrochemical unit may be the same as or different from the anode layer of the first electrochemical unit (when present) and / or when x is from 1 to 8, the anode layer of the second electrochemical unit (when present).

[0036] The bipolar solid-state battery cell further includes an anode current collector. The anode current collector may be any anode current collector known in the art. Advantageously, the anode current collector contains copper or consists essentially of copper.

[0037] The bipolar solid-state battery cell further includes an electrically insulating layer. Advantageously, the electrically insulating layer is arranged to electrically resist the voltage of the bipolar solid-state battery cell during use.

[0038] Advantageously, the electrically insulating layer is provided at the outer surface of the cathode current collector and / or at the outer surface of the anode current collector. Advantageously, the electrically insulating layer is provided at the outer surface of the cathode current collector. Advantageously and alternatively, the electrically insulating layer is provided at the outer surface of the anode current collector.

[0039] In the present disclosure, the "outer surface" of a layer of the bipolar solid-state battery cell refers to the surface facing outside the battery cell, i.e., the surface opposite to the surface facing the solid electrolyte.

[0040] Advantageously, the electrically insulating layer contains a polymer, a ceramic material, or a combination of two or more thereof or consists essentially of a polymer, a ceramic material, or a combination of two or more thereof.

[0041] Advantageously, the polymer is selected from polyethylene, polypropylene, polystyrene, polytetrafluoroethylene, cellulose, viscose, natural rubber and synthetic rubber, but is not limited thereto.

[0042] Advantageously, the ceramic material is selected from glass, metal oxides, metal nitrides, porcelain and mica, but is not limited thereto. Preferred examples of metal oxides are alumina. Preferred examples of metal nitrides are boron nitride.

[0043] According to a second aspect of the present invention, there is provided a bipolar solid state battery pack as described in the appended claims.

[0044] The bipolar solid state battery pack includes at least two bipolar solid state battery pack cells or consists essentially of at least two bipolar solid state battery pack cells. The bipolar solid state battery pack cells are stacked. Advantageously, at least one, and preferably all, of the at least two bipolar solid state battery pack cells are according to the first aspect of the present disclosure.

[0045] Advantageously, the cathode current collectors of at least two (and preferably each) of the at least two bipolar solid state battery pack cells are electrically connected together, in particular by connection to the cathode tab. This advantageously allows the cathode current collector to be easily coupled to an electronic circuit, in particular an external electronic circuit (i.e., outside or external to the battery pack cell).

[0046] Similarly, and advantageously, the anode current collectors of at least two (and preferably each) of the at least two bipolar solid state battery pack cells are electrically connected together, in particular by connection to the anode tab. This advantageously allows the anode current collector to be easily coupled to an electronic circuit, in particular an external electronic circuit (i.e., outside or external to the battery pack cell).

[0047] Advantages of the bipolar solid state battery pack cells of the present disclosure include, but are not limited to, improved functionality due to the ability to stack multiple electrochemical cells, and improved safety, with the risk of thermal runaway reduced or even minimized, thereby protecting the components of the battery pack cell, in particular the cathode electrolyte, anode (if present) and / or electrolyte. Safety is further improved by reducing the risk of leakage of harmful gases released from the battery pack components.

[0048] Another advantage of the bipolar solid state battery pack cells of the present disclosure is the ability to stack multiple bipolar SSB cells, thereby obtaining a bipolar solid state battery pack with increased safety compared to existing SSBs. This increase in safety is obtained by (but is not limited to) ensuring protection against thermal runaway (especially in the case of overvoltage or overcharge). BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Aspects of the present invention will now be described in more detail with reference to the drawings, in which like reference numerals represent like features, and in which:

[0050] - Figures 1 to 9 Schematically represent a bipolar solid-state battery pack cell according to the present disclosure.

[0051] - Figure 10 Schematically represent a bipolar solid-state battery pack according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0053] Figure 1 Schematically show a bipolar solid-state battery pack cell 1 according to the present disclosure. The bipolar solid-state battery pack cell 1 includes a cathode current collector 2, a first electrochemical unit 3a, a third electrochemical unit 3b, and an anode current collector 8. The bipolar solid-state battery pack cell 1 does not include any second electrochemical units, i.e., x is 0.

[0054] Advantageously, the anode current collector 8 is as described above. Advantageously, the cathode current collector 2 is as described above.

[0055] Advantageously, and as is known in the art, the cathode current collector 2 extends from the bipolar solid-state battery pack cell 1. In other words, the cathode current collector 2 advantageously has a portion that extends or protrudes from the stack including the first electrochemical unit 3a and the third electrochemical unit 3b. This can be achieved by methods known in the art, for example, by providing a cathode current collector 2 with a surface area larger than the surface area of the components of the first electrochemical unit 3a. As is well known, such an extension or protrusion allows the cathode current collector 2 to be easily connected or coupled to any electronic circuit (not shown), and the anode current collector 8 is also advantageously connected or coupled to this electronic circuit. Such an electronic circuit particularly includes any external electronic circuit, i.e., an electronic circuit located outside or external to the battery pack cell.

[0056] Advantageously, and as is known in the art, the anode current collector 8 extends from the bipolar solid-state battery pack cell 1. In other words, the anode current collector 8 advantageously has a portion that extends or protrudes from the stack including the first electrochemical unit 3a and the third electrochemical unit 3b. This can be achieved by methods known in the art, for example, by providing an anode current collector 8 with a surface area larger than the surface area of the components of the third electrochemical unit 3b. As is well known, such an extension or protrusion allows the anode current collector 8 to be easily connected or coupled to any electronic circuit (not shown), and the cathode current collector 2 is also advantageously connected or coupled to this electronic circuit. Such an electronic circuit particularly includes any external electronic circuit, i.e., an electronic circuit located outside or external to the battery pack cell.

[0057] An electrical insulating layer 9 is provided at the surface of the cathode current collector 2 opposite to the surface facing the first electrochemical unit 3a.

[0058] Advantageously, when stacking two or more bipolar solid-state battery cells 1 to obtain a bipolar solid-state battery pack, the electrical insulation layer 9 can electrically insulate adjacent bipolar solid-state battery cells 1. In other words, the electrical insulation layer 9 is arranged such that no current is transferred from one bipolar solid-state battery cell 1 to an adjacent bipolar solid-state battery cell 1 below a given threshold.

[0059] Advantageously, the threshold is defined by the thickness of the electrical insulation layer 9 and its dielectric constant. As is well known, the dielectric constant is defined by the material constituting the electrical insulation layer 9.

[0060] Advantageously, the thickness of the electrical insulation layer 9 is selected according to a specific value of the voltage defined by the electrochemical cells (3a, 3b and 4 ( Figure 1 (not shown in the figure)) of the bipolar solid-state battery cell 1 and according to a set value of the voltage defining the safe operating conditions of the bipolar solid-state battery cell 1.

[0061] Advantageously, the material, dielectric constant and / or thickness of the electrical insulation layer 9 are selected to ensure the required level of electrical insulation of the bipolar solid-state battery cell 1 to avoid damage to the electrochemical cells. Therefore, the electrical insulation layer 9 should be regarded as an adjustable dielectric breakdown circuit element. Advantageously, the dielectric constant, material and / or thickness are selected to match the electrical insulation layer 9 with the required dielectric breakdown voltage.

[0062] Advantageously, when the total charging voltage of the bipolar solid-state battery cell 1 exceeds a certain value, the electrical insulation layer 9 enters a dielectric breakdown state. Advantageously, in this dielectric breakdown state, the electrical insulation layer 9 becomes conductive. Therefore, the electrical insulation layer 9 in the dielectric breakdown state allows current to bypass the electrochemical cells 3a and 3b (and 4 ( Figure 1 (not shown in the figure)), thereby avoiding damage to the electrochemical cells 3a, 3b and 4 ( Figure 1 (not shown in the figure)).

[0063] In other words, the electrical insulation layer 9 can advantageously be regarded as acting as a Zener diode. Under normal operating conditions, the electrical insulation layer 9 acts as an insulator. Under extreme conditions, especially when overvoltage and / or overcurrent occur, the electrical insulation layer 9 becomes conductive, thereby preventing thermal runaway. Advantageously, thermal runaway is prevented by passing the energy through an engineered short circuit including the electrical insulation layer 9. Therefore, electrical energy is advantageously not absorbed by the cathode electrolyte, the anode (if present, Figure 1 (not shown in the figure)) and / or the electrolyte, thereby avoiding damage to them.

[0064] Advantageously, an electrically insulating layer 9 is provided such that the layer 9 protects adjacent bipolar solid-state battery cells of the stacked bipolar solid-state battery pack from overvoltage at a value greater than 1 times (such as at least 1.1 times, at least 1.2 times, at least 1.25 times, at least 1.5 times, at least 1.75 times or at least 2 times) the nominal charging voltage of the bipolar solid-state battery cells. In particular, the electrically insulating layer 9 is provided such that according to the UN38 test, the bipolar solid-state battery pack including a stack of at least two bipolar solid-state battery cells is considered safe. The first electrochemical cell 3a includes a first cathode electrolyte layer 5a, a first solid electrolyte 6a, and a first electronic conductor 7.

[0065] Advantageously, the first cathode electrolyte layer 5a is as described above. Advantageously, the first cathode electrolyte layer 5a contains 50 wt% to 100 wt% of a first active material based on the total weight of the first cathode electrolyte layer 5a.

[0066] Advantageously, the first solid electrolyte 6a is as described above.

[0067] Advantageously, the first electronic conductor 7 is as described above. Advantageously, the first electronic conductor 7 is arranged to limit and even substantially prevent ion transport between the first electrochemical cell 3a and the third electrochemical cell 3b. In other words, the electronic conductor advantageously provides ionic resistance while ensuring electronic conductivity between adjacent electrochemical cells 3a, 3b. Thus, due to the electronic conductivity between adjacent electrochemical cells 3a, 3b, the first electrochemical cell 3a and the third electrochemical cell 3b of the bipolar solid-state battery cell 1 of the bipolar solid-state battery pack are considered to be connected in series.

[0068] The third electrochemical cell 3b includes a third cathode electrolyte layer 5c and a third solid electrolyte 6c. Advantageously, the third cathode electrolyte layer 5c is as described above. Advantageously, the third solid electrolyte 6c is as described above.

[0069] Advantageously, the third cathode electrolyte layer 5c contains 50 wt% to 100 wt% of a third active material based on the total weight of the third cathode electrolyte layer 5c.

[0070] Figure 2 Another bipolar solid-state battery cell 100 according to the present disclosure is shown. The bipolar solid-state battery cell 100 includes a cathode current collector 2, a first electrochemical cell 3a, a third electrochemical cell 3b, and an anode current collector 8, all of which are advantageously as described above.

[0071] The bipolar solid-state battery cell 100 further includes an electrically insulating layer 9. The electrically insulating layer 9 is provided at a side or surface of the anode current collector 8 opposite to the side or surface adjacent to the third electrochemical cell 3b. The electrically insulating layer 9 is advantageously as described above.

[0072] Figure 3Shows another bipolar solid-state battery pack cell 101 according to the present disclosure. The bipolar solid-state battery pack cell 101 includes a cathode current collector 2, a first electrochemical unit 3a, a third electrochemical unit 3b, and an anode current collector 8, all of which are advantageously as described above.

[0073] The bipolar solid-state battery pack cell 101 further includes a first electrical insulating layer 9 disposed at a side of the cathode current collector 2 opposite to the side adjacent to the first electrochemical unit 3a. The bipolar solid-state battery pack cell 101 further includes a second electrical insulating layer 9 disposed at a side of the anode current collector 8 opposite to the side adjacent to the third electrochemical unit 3b. The electrical insulating layer 9 is advantageously as described above.

[0074] By disposing the electrical insulating layers 9 (thus when two electrical insulating layers 9 are provided) on both (opposite) sides of the bipolar solid-state battery pack cell 101, when stacking the bipolar solid-state battery pack cells 101 to obtain a bipolar solid-state battery pack, each electrical insulating layer 9 can advantageously be thinner than when a single electrical insulating layer 9 is provided, because each electrical insulating layer 9 contributes to the electrical insulation of the adjacent bipolar solid-state battery pack cells 101 of the bipolar solid-state battery pack.

[0075] Figure 4 Shows a bipolar solid-state battery pack cell 102 according to another embodiment of the present invention. The bipolar solid-state battery pack cell 102 includes an electrical insulating layer 9 disposed on the surface of the cathode current collector 2 (which is opposite to the surface of the cathode current collector 2 adjacent to the first electrochemical unit 3a). The bipolar solid-state battery pack cell 102 further includes a third electrochemical unit 3b and an anode current collector 8. Advantageously, each of the electrical insulating layer 9, the anode current collector 8, and the cathode current collector 2 is as described above.

[0076] The first electrochemical unit 3a includes a first cathode electrolyte 5a, a first solid electrolyte 6a, a first anode layer 10a, and a first electronic conductor 7. The first anode layer 10a is advantageously disposed between the first solid electrolyte 6a and the first electronic conductor 7. Advantageously, each of the first cathode electrolyte 5a, the first solid electrolyte 6a, the first anode layer 10a, and the first electronic conductor 7 is as described above.

[0077] The third electrochemical unit 3b includes a third cathode electrolyte 5c, a third solid electrolyte 6c, and a third anode layer 10c. The third anode layer 10c is advantageously disposed between the third solid electrolyte 6c and the anode current collector 8. Advantageously, each of the third cathode electrolyte 5c, the third solid electrolyte 6c, and the third anode layer 10c is as described above.

[0078] Advantageously, the first anode layer 10a and / or the third anode layer 10c comprises a metal layer or consists essentially of a metal layer. The metal of the metal layer can be the same as or different from the metal contained in the cathode (e.g., the cathode active material). For example, when the cathode contains lithium, the anode layer is advantageously a metal layer containing lithium or consisting essentially of lithium. For example, the anode layer can be a lithium foil, optionally doped or substituted with aluminum.

[0079] Alternatively, and equally advantageously, the anode comprises an intercalation anode or consists essentially of an intercalation anode. Non-limiting examples of suitable intercalation electrodes include graphite and Li4Ti5O 12 , or a combination thereof.

[0080] Alternatively, and equally advantageously, the first anode layer 10a and / or the third anode layer 10c comprises a conversion electrode or consists essentially of a conversion electrode. Advantageously, the conversion electrode comprises an oxide, a nitride, a sulfide, or a combination of two or more thereof, or consists essentially of an oxide, a nitride, a sulfide, or a combination of two or more thereof. Non-limiting examples of oxides include LiVO2 and SnO2. Non-limiting examples of nitrides include vanadium nitride (VN) and molybdenum nitride (δ-MoN). Non-limiting examples of sulfides include tin sulfide (SnS x ) and vanadium sulfide (VS2 and VS4).

[0081] Advantageously, the first anode layer 10a and / or the third anode layer 10c can be provided by a manner known in the art, such as by providing a film, a sheet, or a foil, or by depositing a layer by known methods such as sputtering and plasma deposition.

[0082] Figure 5 FIG. 103 shows a bipolar solid-state battery cell 103 according to another embodiment of the present invention. The bipolar solid-state battery cell 103 includes an electrically insulating layer 9 disposed at a surface of the anode current collector 8 (which is opposite to the surface of the anode current collector 8 adjacent to the third electrochemical cell 3b). The bipolar solid-state battery cell 103 further includes a first electrochemical cell 3a and a cathode current collector 2. Advantageously, each of the electrically insulating layer 9, the anode current collector 8, and the cathode current collector 2 is as described above.

[0083] The first electrochemical cell 3a and the third electrochemical cell 3b are advantageously as described above for the Figure 4 bipolar solid-state battery cell 102, and include a first anode layer 10a and a third anode layer 10c, respectively.

[0084] Figure 6Shows a bipolar solid-state battery pack cell 104 according to another embodiment of the present invention. The bipolar battery pack cell 104 includes an electrically insulating layer 9 disposed at a surface of the cathode current collector 2 that is opposite to the surface of the cathode current collector 2 adjacent to the first electrochemical cell 3a. The bipolar battery pack cell 104 further includes a second electrically insulating layer 9 disposed at a surface of the anode current collector 8 that is opposite to the surface of the anode current collector 8 adjacent to the third electrochemical cell 3b.

[0085] Advantageously, each of the electrically insulating layer 9, the anode current collector 8, and the cathode current collector 2 is as described above. Advantageously, the first electrochemical cell 3a and the third electrochemical cell 3b are as described above for Figure 4 the bipolar solid-state battery pack cell 102, and thus include a first anode layer 10a and a third anode layer 10c, respectively.

[0086] Figure 7 Shows a bipolar solid-state battery pack cell 105 according to another embodiment of the present invention. The bipolar solid-state battery pack cell 105 includes an electrically insulating layer 9 disposed at a surface of the cathode current collector 2 (which is opposite to the surface of the cathode current collector 2 adjacent to the first electrochemical cell 3a). The bipolar solid-state battery pack cell 105 further includes a third electrochemical cell 3b and an anode current collector 8.

[0087] The first electrochemical cell 3a advantageously includes a first cathode electrolyte 5a, a first electrolyte 6a, and a first electronic conductor 7, which are advantageously as described above.

[0088] The third electrochemical cell 3b advantageously includes a third cathode electrolyte 5c and a third electrolyte 6c, which are advantageously as described above.

[0089] The bipolar solid-state battery pack cell 105 further includes a second electrochemical cell 4, i.e., x is 1. The second electrochemical cell 4 includes a second cathode electrolyte 5b, a second solid electrolyte 6b, and a second electronic conductor 11. Advantageously, the second cathode electrolyte 5b and the second solid electrolyte 6b are as described above. Advantageously, the second electronic conductor 11 is as described above, particularly as described above for the first electronic conductor 7.

[0090] Advantageously, the first electronic conductor 7 of the first electrochemical cell 3a is arranged to limit and even substantially prevent ion transfer between the first electrochemical cell 3a and the second electrochemical cell 4. In other words, the first electronic conductor 7 advantageously provides ionic resistance while ensuring electronic conductivity between the adjacent electrochemical cells 3a and 4.

[0091] Advantageously, the second electronic conductor 11 of the second electrochemical cell 4 is arranged so as to limit and even substantially prevent ion transfer between the second electrochemical cell 4 and the third electrochemical cell 3b. In other words, the second electronic conductor 11 advantageously provides an ionic resistance while ensuring electronic conductivity between the adjacent electrochemical cells 4 and 3b.

[0092] Figure 8 Figure 106 of a bipolar solid-state battery cell according to yet another embodiment of the present invention is shown. The bipolar solid-state battery cell 106 includes an electrically insulating layer 9 disposed at the surface of the cathode current collector 2 (which is opposite to the surface of the cathode current collector 2 adjacent to the first electrochemical cell 3a). The bipolar solid-state battery cell 106 further includes a third electrochemical cell 3b and an anode current collector 8. The first electrochemical cell 3a and the third electrochemical cell 3b are advantageously as described for Figure 7 the bipolar solid-state battery cell 105.

[0093] The bipolar solid-state battery cell 106 further includes two second electrochemical cells 4, i.e., x = 2. Each second electrochemical cell 4 advantageously includes a second cathode electrolyte 5b, a second solid electrolyte 6b, and a second electronic conductor 11. Advantageously, the individual second cathode electrolyte 5b, the individual second solid electrolyte 6b, and the second electronic conductor 11 are as described above.

[0094] Advantageously, the second electronic conductor 11 of the first second electrochemical cell 4 is arranged so as to limit and even substantially prevent ion transfer between the adjacent second electrochemical cells 4. Advantageously, the second electronic conductor 11 of the second second electrochemical cell 4 is arranged so as to limit and even substantially prevent ion transfer between the second electrochemical cell 4 and the third electrochemical cell 3b.

[0095] Figure 9 Figure 107 of a bipolar solid-state battery cell according to yet another embodiment of the present invention is shown. The bipolar solid-state battery cell 107 includes an electrically insulating layer 9 disposed at the surface of the anode current collector 8 that is opposite to the surface of the anode current collector 8 adjacent to the third electrochemical cell 3b. The bipolar solid-state battery cell 106 further includes a first electrochemical cell 3a and a cathode current collector 2.

[0096] The first electrochemical cell 3a advantageously includes a first cathode electrolyte 5a, a first electrolyte 6a, a first anode layer 10a, and a first electronic conductor 7, which are advantageously as described above.

[0097] The third electrochemical cell 3b advantageously includes a third cathode electrolyte 5c, a third electrolyte 6c, and a third anode layer 10c, which are advantageously as described above.

[0098] The bipolar solid-state battery pack cell 107 further includes a second electrochemical cell 4, i.e., x is 1. The second electrochemical cell 4 includes a second cathode electrolyte 5b, a second solid electrolyte 6b, a second anode layer 10b, and a second electronic conductor 11. Advantageously, the second cathode electrolyte 5b, the second solid electrolyte 6b, the second anode layer 10b, and the second electronic conductor 11 are as described above.

[0099] Figure 10 Fig. shows a bipolar solid-state battery pack 200 according to the present disclosure. The bipolar solid-state battery pack 200 includes a stack of two bipolar solid-state battery pack cells 107. The presence of the electrically insulating layer 9 allows a single bipolar solid-state battery pack cell 107 to operate safely as described above.

[0100] The cathode current collector 2 of the bipolar solid-state battery pack cell 107 advantageously extends or protrudes from a stack including a first electrochemical cell 3a, a second electrochemical cell 4, and a third electrochemical cell 3b. This allows them to be easily interconnected. As Figure 10 shown, the cathode current collector 2 of the bipolar solid-state battery pack cell 107 is electrically connected by means of a cathode tab 12.

[0101] The anode current collector 8 of the bipolar solid-state battery pack cell 107 advantageously extends or protrudes from a stack including a first electrochemical cell 3a, a second electrochemical cell 4, and a third electrochemical cell 3b. This allows them to be easily interconnected. As Figure 10 shown, the anode current collector 8 of the bipolar solid-state battery pack cell 107 is electrically connected by means of an anode tab 13.

[0102] Advantageously, the cathode current collector 2 extends or protrudes in a first direction, and the anode current collector 8 extends or protrudes in a second direction different from the first direction. This allows the cathode current collector 2 to be easily connected to the cathode tab 12, and the anode current collector 8 to be easily connected to the anode tab 13 as well. Embodiment

[0103] Example 1

[0104] Manufacture a bipolar solid-state battery pack cell 102 (i.e., x is 0) as shown in the schematic diagram according to Figure 4 of.

[0105] The cathode current collector 2 is made of an aluminum sheet, and the anode current collector 8 is made of a copper foil.

[0106] The first cathode electrolyte 5a and the third cathode electrolyte 5c contain NMC as the active material, carbon nanotubes (CNT) as the electronically conductive compound, and LLZO as the ionically conductive compound.

[0107] The first solid electrolyte 6a and the third solid electrolyte 6c contain LLZO. A 25-μm-thick lithium foil is provided as the first anode layer 10a and the third anode layer 10c. The first layer of electronic conductor 7 is an 8-μm-thick stainless steel foil.

[0108] At the side of the aluminum cathode current collector 2 opposite to its side adjacent to the first cathode electrolyte 5a, a polyethylene foil with a thickness of 600 nm to 800 nm is provided as the electrical insulation layer 9.

[0109] All layers are stacked in an argon atmosphere to avoid contamination, and the bipolar solid battery cell is sealed with a pneumatic press.

[0110] The voltage is measured, and the voltage on the cathode current collector 2 of the first electrochemical unit 3a and the electronic conductor 7 is determined to be 8.4 V to 8.8 V, or 4.2 V to 4.4 V, and the voltage on the electronic conductor 7 and the anode current collector 8 via the third electrochemical unit 3b is 4.2 V to 4.4 V.

[0111] Symbol Table

[0112] 1. Bipolar solid battery cell

[0113] 2. Cathode current collector

[0114] 3a. First electrochemical unit

[0115] 3b. Third electrochemical unit

[0116] 4. Second electrochemical unit

[0117] 5a. First cathode electrolyte layer

[0118] 5b. Second cathode electrolyte layer

[0119] 5c. Third cathode electrolyte layer

[0120] 6a. First solid electrolyte

[0121] 6b. Second solid electrolyte

[0122] 6c. Third solid electrolyte

[0123] 7. First electronic conductor

[0124] 8. Anode current collector

[0125] 9. Electrical insulation layer

[0126] 10a. First anode layer

[0127] 10b. Second anode layer

[0128] 10c. Third anode layer

[0129] 11. Second electronic conductor

[0130] 12. Cathode tab for external connection

[0131] 13. Anode tab for external connection

[0132] 100. Bipolar solid-state battery cell

[0133] 101. Bipolar solid-state battery cell

[0134] 102. Bipolar solid-state battery cell

[0135] 103. Bipolar solid-state battery cell

[0136] 104. Bipolar solid-state battery cell

[0137] 105. Bipolar solid-state battery cell

[0138] 106. Bipolar solid-state battery cell

[0139] 107. Bipolar solid-state battery cell

[0140] 200. Bipolar solid-state battery pack

Claims

1. Bipolar solid-state battery cells (1, 100, 101, 102, 103, 104, 105, 106, 107), comprising a plurality of electrochemical cells (3a, 3b, 4) arranged in a stack such that adjacent electrochemical cells share an electronic conductor (7, 11), said bipolar solid-state battery cells (1, 100, 101, 102, 103, 104, 105, 106, 107) comprising: - A cathode current collector (2); - A first electrochemical cell (3a), which includes a first cathode electrolyte layer (5a), a first solid electrolyte (6a), and a first electronic conductor (7), and said first cathode electrolyte layer (5a) contains a first active material; - x second electrochemical cells (4), where each second electrochemical cell (4) includes a second cathode electrolyte layer (5b), a second solid electrolyte (6b), and a second electronic conductor (11), and said second cathode electrolyte layer (5b) contains a second active material; - A third electrochemical cell (3b), which includes a third cathode electrolyte layer (5c) and a third solid electrolyte (6c), and said third cathode electrolyte layer (5c) contains a third active material; And - An anode current collector (8); Wherein said plurality of stacked electrochemical cells (3a, 3b, 4) are arranged in series, and the number x of the second electrochemical cells (4) is from 0 to 8, Characterized in that said bipolar solid-state battery cells (1, 100, 101, 102, 103, 104, 105, 106, 107) further include an electrically insulating layer (9) provided on the outer surface of said cathode current collector (2) and / or the outer surface of said anode current collector (8), and includes a ceramic material.

2. The bipolar solid-state battery cell (1, 100, 101, 102, 103, 104, 105, 106, 107) according to claim 1, wherein said electrically insulating layer (9) is arranged to electrically resist the voltage of the bipolar solid-state battery cell during use.

3. The bipolar solid-state battery cell (1, 100, 101, 102, 103, 104, 105, 106, 107) according to any one of the preceding claims, wherein said electrically insulating layer (9) further contains a polymer.

4. The bipolar solid-state battery cell (1, 100, 101, 102, 103, 104, 105, 106, 107) according to claim 3, wherein said polymer is selected from polyethylene, polypropylene, polystyrene, polytetrafluoroethylene, cellulose, viscose, natural rubber, and synthetic rubber.

5. The bipolar solid-state battery cell (1, 100, 101, 102, 103, 104, 105, 106, 107) according to any one of the preceding claims, wherein said ceramic material is selected from glass, metal oxides, metal nitrides, porcelain, and mica.

6. The bipolar solid-state battery cell (1, 100, 101, 102, 103, 104, 105, 106, 107) according to any one of the preceding claims, wherein the first electronic conductor (7) and the second electronic conductor (11) each independently comprise steel, a steel alloy, titanium, a titanium alloy, vitreous carbon, or a combination of two or more thereof.

7. The bipolar solid-state battery cell (102, 103, 104, 107) according to any one of the preceding claims, wherein the first electrochemical unit (3a) further comprises a first anode layer (10a), and / or the third electrochemical unit (3c) further comprises a third anode layer (10c).

8. The bipolar solid-state battery cell (107) according to any one of the preceding claims, wherein x is from 1 to 8, and wherein the second electrochemical unit (4) further independently comprises a second anode layer (10b).

9. The bipolar solid-state battery cell (102, 103, 104, 107) according to any one of claims 7 to 8, wherein the anode layers (10a, 10b, 10c) comprise an alkali metal, an alkaline earth metal, a transition metal, graphite, silicon, a carbide, or a combination of two or more thereof.

10. A bipolar solid-state battery cell (1, 100, 101, 102, 103, 104, 105, 106, 107) according to any one of the preceding claims, wherein the first solid electrolyte (6a), the second solid electrolyte (6b), if present, and the third solid electrolyte (6c) each comprise an alkali metal, an alkaline earth metal, a transition metal or a combination thereof, preferably lithium, sodium, magnesium or aluminum, more preferably Li7La3Zr2O 12 (LLZO).

11. The bipolar solid-state battery cell (1, 100, 101, 102, 103, 104, 105, 106, 107) according to any one of the preceding claims, wherein the first cathode electrolyte layer (5a), the second cathode electrolyte layer (5b), if present, and the third cathode electrolyte layer (5c) each further comprise one or more of an electronically conductive compound and an ionically conductive compound.

12. A bipolar solid-state battery pack (200) comprises a stack of at least two bipolar solid-state battery cells (1, 100, 101, 102, 103, 104, 105, 106, 107) according to any one of the preceding claims.

13. The bipolar solid-state battery pack (200) according to claim 12, wherein the cathode current collector (2) of each of the at least two bipolar solid-state battery cells (1, 100, 101, 102, 103, 104, 105, 106, 107) is electrically connected to a cathode tab (12).

14. The bipolar solid-state battery pack (200) according to any one of claims 12 to 13, wherein the anode current collector (8) of each of the at least two bipolar solid-state battery cells (1, 100, 101, 102, 103, 104, 105, 106, 107) is electrically connected to an anode tab (13).

Images