Lithium metal battery monomer, battery device and power utilization device

Abstract

The utility model discloses a lithium metal battery monomer, a battery device and a power utilization device, the lithium metal battery monomer comprises a shell, a battery cell assembly and an oxide aerogel sheet, the battery cell assembly is located in the shell, and the battery cell assembly comprises a lithium metal negative electrode and a lithium metal positive electrode which are stacked; the oxide aerogel sheet is located between the shell and the battery cell assembly, and at least part of the orthographic projection of the oxide aerogel sheet on the battery cell assembly covers the battery cell assembly in the preset direction. According to the lithium metal battery cell disclosed by the invention, the oxide aerogel sheet is arranged between the shell and the battery cell assembly, when the lithium metal battery cell is subjected to thermal runaway, lithium metal liquid flow can be sprayed out from the battery cell assembly, and the oxide aerogel sheet can be subjected to chemical reaction with the lithium metal liquid flow, so that the corrosion of the lithium metal liquid flow to the shell can be effectively reduced; therefore, the safety of the lithium metal battery monomer is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a lithium metal battery monomer, a battery device and a power consumption device. BACKGROUND

[0002] When the cell assembly is in thermal runaway, the internal high-temperature molten lithium metal liquid will be sprayed out at a very high pressure from the weak side of the winding structure. These metal liquid streams with a temperature exceeding 1800℃ have very strong penetration and corrosive properties, and will directly impact the stainless steel shell. The strength of stainless steel decreases sharply at extremely high temperatures (the tensile strength decreases by about 90% at 1000℃), and the lithium metal will react violently with the stainless steel to generate a low-melting-point eutectic compound, causing the shell to be molten and penetrated in a short time. CONTENT OF THE UTILITY MODEL

[0003] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, one object of the present application is to provide a lithium metal battery monomer, which is provided with an oxide aerogel sheet between the shell and the cell assembly. The oxide aerogel sheet can chemically react with lithium elements in the lithium metal liquid stream, and can effectively reduce the corrosion of the lithium metal liquid stream on the shell, so as to improve the safety of the lithium metal battery monomer.

[0004] The present application also provides a battery device having the above-mentioned lithium metal battery monomer.

[0005] The present application also provides a power consumption device having the above-mentioned battery device.

[0006] According to the lithium metal battery monomer of the first aspect of the present application, the shell, the cell assembly located in the shell, the cell assembly including a lithium metal negative electrode and a positive electrode stacked and arranged, and the oxide aerogel sheet located between the shell and the cell assembly and along a preset direction, at least part of the orthogonal projection of the oxide aerogel sheet on the cell assembly covers the cell assembly; wherein the preset direction is at least one of the height direction, the length direction or the width direction of the cell assembly.

[0007] According to the lithium metal battery monomer of the present application, the oxide aerogel sheet is arranged between the shell and the cell assembly. When the lithium metal battery monomer is in thermal runaway, the lithium metal liquid stream will be sprayed out from the cell assembly. The oxide aerogel sheet can chemically react with lithium elements in the lithium metal liquid stream, and can effectively reduce the corrosion of the lithium metal liquid stream on the shell, so as to improve the safety of the lithium metal battery monomer.

[0008] In some embodiments, the cell assembly has a first side and a second side, the area of the first side is greater than the area of the second side, and the oxide aerogel sheet is located between the second side and the shell.

[0009] The oxide aerogel sheet is arranged between the second side surface and the shell, and when thermal runaway occurs in the lithium metal battery monomer, the lithium metal liquid is prone to be sprayed out from the second side surface. Therefore, the oxide aerogel sheet arranged between the second side surface and the shell can correspondingly resist the lithium metal liquid.

[0010] In some embodiments, in a projection plane perpendicular to the second side surface, a projection plane of the oxide aerogel sheet is located in a projection plane of the second side surface.

[0011] The area of the second side surface is greater than the area of the oxide aerogel sheet, and when the oxide aerogel sheet is arranged between the shell and the second side surface, the oxide aerogel sheet is not easy to stretch out from the second side surface, thereby avoiding interference with the installation of the shell.

[0012] In some embodiments, the electric core assembly and the shell have a spacing space therebetween, and along a thickness direction of the oxide aerogel sheet, the spacing space has a distance D1, and the thickness of the oxide aerogel sheet is D2, and D2≤1 / 2D1 is satisfied.

[0013] The thickness of the oxide aerogel sheet is less than or equal to half of the distance between the electric core assembly and the shell, which can ensure that the electric core assembly and the shell do not extrude the oxide aerogel sheet, and the oxide aerogel sheet does not occupy the space between the electric core assembly and the shell, and the space between the electric core assembly and the shell is reasonably utilized.

[0014] In some embodiments, the oxide aerogel sheet has a first part and a second part in a direction from the electric core assembly to the shell, the first part is arranged adjacent to the electric core assembly, the second part is arranged adjacent to the shell, and the content of the oxide in the first part is greater than the content of the oxide in the second part.

[0015] The first part is arranged adjacent to the electric core assembly, the second part is arranged adjacent to the shell, and the content of the oxide in the first part is greater than the content of the oxide in the second part. When thermal runaway occurs in the lithium metal battery monomer, the oxide with a large content in the first part reacts with lithium elements in the lithium metal liquid stream, thereby further reducing the impact force of the lithium metal liquid stream on the shell.

[0016] In some embodiments, the oxide aerogel sheet is provided with a plurality of pores, and the diameters of the pores gradually decrease in a direction from the electric core assembly to the shell.

[0017] The diameters of the pores gradually decrease, and the multi-stage pore design enhances the capillary effect and reduces the corrosion pressure of the metal liquid stream on the high-temperature-resistant layer.

[0018] In some embodiments, the diameter of the pores near the cell assembly is 20-50 nm, and the diameter of the pores near the shell is less than 20 nm.

[0019] In the embodiment, the diameter of the pores at the first end is 20-50 nm, and the diameter of the pores at the second end is less than 20 nm. The sizes of the pores at the first end and the second end are reasonably arranged, so that the oxide aerogel sheet has good supporting performance.

[0020] In some embodiments, the lithium metal battery cell further comprises: a protective film wrapped on the outer circumferential side of the oxide aerogel sheet.

[0021] In the embodiment, the protective film is arranged on the outer circumferential side of the oxide aerogel sheet, so as to prevent the debris remaining on the outer circumferential side of the oxide aerogel sheet from falling off the oxide aerogel sheet.

[0022] In some embodiments, the oxide in the oxide aerogel sheet is SiO2, Al2O3, or MgO.

[0023] In the embodiment, different oxide aerogel sheets formed by different oxides can be flexibly configured according to actual needs to meet different needs. Moreover, the oxide aerogel sheets formed by different oxides can effectively react with lithium elements in the lithium metal liquid stream while blocking the lithium metal liquid stream flowing toward the shell, so as to hinder the erosion of the lithium elements to the shell.

[0024] In some embodiments, the oxide aerogel sheet comprises a SiO2 aerogel sheet.

[0025] In the embodiment, the oxide aerogel sheet comprises a SiO2 aerogel sheet, so that the oxide aerogel sheet has good heat insulation effect.

[0026] In some embodiments, the oxide aerogel sheet comprises a fumed SiO2 sheet.

[0027] In the embodiment, the oxide aerogel sheet comprises a fumed SiO2 sheet, so that the oxide aerogel sheet has good heat insulation effect.

[0028] According to the battery device of the second aspect of the application, the lithium metal battery cell of the first aspect of the application is included.

[0029] According to the power utilization device of the application, the performance of the battery device is improved, so as to improve the working power utilization performance of the power utilization device.

[0030] According to the power utilization device of the third aspect of the application, the battery device of the second aspect of the application is included.

[0031] According to the electrical device of this application, the improved performance of the battery device is beneficial to improving the electrical performance of the electrical device.

[0032] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0033] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0034] Figure 1 This is a schematic diagram of a vehicle according to some embodiments of this application;

[0035] Figure 2 These are schematic diagrams of battery devices according to some embodiments of this application;

[0036] Figure 3 This is a schematic diagram of a lithium metal battery cell according to some embodiments of this application;

[0037] Figure 4 yes Figure 3 Side view of a single lithium metal battery cell;

[0038] Figure 5 yes Figure 3 A 3D view of a single lithium metal battery cell;

[0039] Figure 6 yes Figure 5 Enlarged view of point A in the middle.

[0040] Figure label:

[0041] 100. Vehicle; 101. Battery unit; 1011. Upper housing; 1012. Lower housing; 1013. Receiving cavity; 102. Controller; 103. Motor;

[0042] 10. Lithium metal battery cells;

[0043] 11. Housing; 12. Battery cell assembly; 121. First side; 122. Second side; 13. Oxide aerogel sheet. Detailed Implementation

[0044] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0045] At present, from the development of market situation, the application of power battery is more and more widely. Power battery is not only applied to energy storage power supply system of water power, thermal power, wind power and solar power station, but also widely used in electric bicycles, electric motorcycles, electric vehicles and other electric vehicles, aerospace and other fields. With the continuous expansion of the application field of power battery, the demand of its market is also increasing.

[0046] When the lithium metal battery cell assembly experiences thermal runaway, the internal high-temperature molten lithium metal liquid will be ejected from the weak side of the winding structure at extremely high pressure. These metal liquid streams with a temperature exceeding 1800°C have extremely strong penetration and corrosive properties, which will directly impact the shell. The shell of the lithium metal battery monomer is generally made of stainless steel material. The strength of stainless steel decreases sharply at extremely high temperature (the tensile strength decreases by about 90% at 1000°C), and the lithium metal reacts with stainless steel to generate low-melting-point eutectic compounds, causing the shell to be eroded and penetrated in a short time, triggering a more serious chain reaction.

[0047] 1. Protection against extreme thermal shock:

[0048] The high temperature (up to 800°C or more) and high pressure (several MPa) generated instantaneously inside the cell during thermal runaway will quickly destroy the cell packaging structure, causing the side to break. At this time, the ejected high-temperature molten lithium metal has extremely strong thermal erosion. How to resist this extreme thermal shock in a very short time is the primary problem.

[0049] 2. Chemical erosion of lithium metal liquid stream:

[0050] Molten lithium metal has extremely high chemical activity and will react violently with the stainless steel shell (such as forming intermetallic compounds with Fe, Cr, Ni, etc.), accompanied by a large amount of heat release, further accelerating the shell melting. How to block or slow down this high-temperature chemical corrosion is crucial.

[0051] 3. Chain reaction of structural failure:

[0052] Once the shell is melted, it will cause secondary hazards such as electrolyte splashing and oxygen intrusion, which may trigger a fire or even an explosion. How to prevent local melting from evolving into systematic thermal runaway diffusion is a key safety problem that needs to be solved.

[0053] 4. Dynamic pressure release and thermal management:

[0054] Traditional pressure relief designs are mostly for top pressure relief, while side breakage is often disordered, and high-temperature jet flow will randomly impact the weak points of the shell. How to achieve directional pressure relief at a controllable position to avoid the concentrated release of pressure and heat becomes a key issue.

[0055] 5. Challenge of multi-physical field coupling:

[0056] This problem involves thermal-mechanical-electric-chemical multi-field coupling: high temperature leads to material performance degradation, pressure fluctuation affects structural strength, and current distribution changes exacerbate local heating. A single protection method is difficult to cope with such complex interactions.

[0057] Based on the above considerations, the present application provides a lithium metal battery monomer, an oxide aerogel sheet is arranged between the shell and the battery cell assembly. When the battery cell assembly undergoes thermal runaway, lithium metal liquid will be ejected from the battery cell assembly, and the oxide aerogel sheet can react with the lithium elements in the lithium metal liquid stream to absorb the lithium elements in the lithium metal liquid stream, effectively reducing the impact of the lithium metal liquid stream on the shell and reducing the pressure on the shell, thereby improving the safety of the lithium metal battery monomer.

[0058] The battery device disclosed in the present application can be used in a power consumption device using the battery device as a power source or a variety of energy storage systems using the battery device as an energy storage element. The power consumption device can be, but is not limited to, a mobile phone, a tablet, a notebook computer, an electric toy, a power tool, an electric vehicle, an electric car, a ship, a spacecraft, etc. Among them, the electric toy can include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric plane toys, etc., and the spacecraft can include airplanes, rockets, space shuttles, and spaceships, etc.

[0059] The following embodiments take a power consumption device of an embodiment of the present application, a vehicle 100, as an example for illustration. The vehicle 100 can be a new energy vehicle, which can be a pure electric vehicle, a hybrid vehicle, or a range extended vehicle, etc. The vehicle 100 is internally provided with a battery device 101, which can be arranged at the bottom, head, or tail of the vehicle 100. The battery device 101 can be used for power supply of the vehicle 100, for example, the battery device 101 can be used as an operating power source of the vehicle 100. The vehicle 100 can further include a controller 102 and a motor 103, the controller 102 is used to control the battery device 101 to supply power to the motor 103, for example, for the working power demand of the vehicle 100 during starting, navigation, and driving.

[0060] In some embodiments of the present application, the battery device 101 can not only be used as an operating power source of the vehicle 100, but also be used as a driving power source of the vehicle 100, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 100.

[0061] The battery device 101 includes a box body and a lithium metal battery monomer 10, the box body includes a lower box body 1012 and an upper box body 1011, the lower box body 1012 and the upper box body 1011 are connected to define a containing cavity 1013, and the lithium metal battery monomer 10 is arranged in the containing cavity. The box body is used to provide a containing space for the lithium metal battery monomer 10.

[0062] Exemplarily, in the battery device 101, the battery cell assembly includes a plurality of lithium metal battery cells 10, which can be connected in series, in parallel or in a mixed manner. The mixed manner means that the plurality of lithium metal battery cells 10 are connected in series and in parallel. The plurality of lithium metal battery cells 10 can be directly connected in series, in parallel or in a mixed manner, and the battery cell assembly formed by the plurality of lithium metal battery cells 10 is accommodated in the accommodation cavity. Of course, the battery device 101 can also be in the form of a plurality of lithium metal battery cells 10 connected in series, in parallel or in a mixed manner to form a battery device 101 module, and a plurality of battery device 101 modules are connected in series, in parallel or in a mixed manner to form a whole and are accommodated in the accommodation cavity. The battery device 101 can also include other structures, for example, the battery device 101 can also include a busbar component for realizing electrical connection between the plurality of lithium metal battery cells 10.

[0063] The lithium metal battery cell 10 can be in the form of a flat body, a cuboid or other shapes.

[0064] Figure 3 is a schematic view of a lithium metal battery cell 10 according to some embodiments of the present application, Figure 4 is Figure 3 is a side view of a lithium metal battery cell 10, Figure 5 is Figure 3 is a perspective view of a lithium metal battery cell 10, Figure 6 is Figure 5 is an enlarged view of A in FIG. 10.

[0065] The lithium metal battery cell 10 according to the first aspect of the present application includes a shell 11, a cell assembly 12 and an oxide aerogel sheet 13. The cell assembly 12 is located in the shell 11, and the cell assembly 12 includes a lithium metal negative electrode and a positive electrode arranged in a stack. The oxide aerogel sheet 13 is located between the shell 11 and the cell assembly 12, and along a predetermined direction. At least part of the orthographic projection of the oxide aerogel sheet 13 on the cell assembly 12 covers the cell assembly 12, wherein the predetermined direction is at least one of the height direction, the length direction or the width direction of the cell assembly 12.

[0066] Exemplarily, the electric cell assembly 12 can include a positive electrode sheet, a lithium metal negative electrode sheet, and a separator film between the positive electrode sheet and the lithium metal negative electrode sheet, and the positive electrode sheet and the negative electrode sheet are wound or laminated to form the electric cell assembly 12. The positive electrode sheet can include a positive electrode current collector (such as an aluminum foil) and a positive electrode film layer disposed on at least one surface of the positive electrode current collector, and the positive electrode film layer includes a positive electrode active material (such as lithium nickel cobalt manganese oxide, etc.); the lithium metal negative electrode sheet can include a negative electrode current collector and a lithium metal film layer disposed on at least one surface of the negative electrode current collector, such as a lithium metal negative electrode formed by rolling a 50um thick lithium metal foil on both sides of the copper foil. Optionally, the lithium metal negative electrode sheet can also not contain the lithium metal film layer, that is, the initial lithium metal negative electrode sheet has no negative electrode active material, and the metal lithium will be deposited on the negative electrode sheet during charging.

[0067] Exemplarily, the preset direction can be the height direction, that is, in the height direction, the oxide aerogel sheet 13 can be disposed on one side or both sides of the electric cell assembly 12, and the oxide aerogel sheet 13 can partially cover the electric cell assembly 12 or completely cover the electric cell assembly, which is not limited in the present application. Similarly, the preset direction can also be the length direction or the width direction, which is not described herein.

[0068] Exemplarily, when the electric cell assembly 12 is in thermal runaway, the internal high-temperature molten lithium metal liquid flow will be concentrated and sprayed out from the weak side of the winding structure at a very high pressure. These metal liquid flows with a temperature exceeding 1800°C have a very strong penetration and corrosive ability, which will directly impact the shell 11. The shell 11 of the lithium metal battery monomer 10 is generally made of stainless steel material, and the strength of the stainless steel decreases sharply at an extremely high temperature (the tensile strength decreases by about 90% at 1000°C). In addition, the lithium metal and the stainless steel will react violently to generate a low-melting-point eutectic compound, which causes the shell 11 to be eroded and penetrated in a short time.

[0069] In the present application, the oxide aerogel sheet 13 is disposed between the shell 11 and the electric cell assembly 12. The oxide aerogel sheet 13 can have excellent heat insulation performance and can effectively block heat transfer, and the mass is relatively light.

[0070] When the lithium metal battery monomer 10 is in thermal runaway, the lithium metal liquid flow is easy to be concentrated and sprayed out from the weak side of the electric cell assembly 12 at a high pressure. The oxide in the oxide aerogel sheet 13 can react with the lithium element in the lithium metal liquid flow to absorb the lithium element in the lithium metal liquid flow, which can effectively reduce the erosion of the lithium metal liquid flow to the shell 11.

[0071] For example, the oxide can be SiO2. The oxide aerogel sheet 13 containing SiO2 has good thermal insulation properties. SiO2 is a non-combustible material with a temperature resistance of up to 600°C or higher. It can better isolate heat transfer to the shell 11 and is not easy to burn at high temperatures.

[0072] For example, the oxide aerogel sheet 13 can be a single piece integrally molded from SiO2. The SiO2-containing aerogel is encapsulated or embedded in a specific mold to form the oxide aerogel sheet 13. This can avoid splicing gaps on the oxide aerogel sheet 13, and the seamless structure is more resistant to vibration and impact.

[0073] For example, oxide aerogel sheet 13 can also be prepared by sol-gel method + drying process.

[0074] According to the lithium metal battery cell 10 of this application, an oxide aerogel sheet 13 is provided between the casing 11 and the cell assembly 12. The oxide aerogel sheet 13 is a one-piece molded part, which can avoid the appearance of splicing gaps on the oxide aerogel sheet 13. The seamless structure is more resistant to vibration and impact. When the lithium metal battery cell 10 experiences thermal runaway, the lithium metal liquid will be ejected from the cell assembly 12. The oxide aerogel sheet 13 can chemically react with the lithium element in the lithium metal liquid to absorb the lithium element in the lithium metal liquid, which can effectively reduce the erosion of the casing 11 by the lithium metal liquid and improve the safety of the lithium metal battery cell 10.

[0075] In some embodiments, the battery cell assembly 12 has a first side 121 and a second side 122, the area of ​​the first side 121 is larger than the area of ​​the second side 122, and the oxide aerogel sheet 13 is located between the second side 122 and the housing 11.

[0076] Reference Figures 2-6 The cell assembly 12 has a first direction (see attached diagram). Figure 5 The two first sides 121 (in the X direction) are set opposite each other and along the second direction (see Appendix) Figure 4 Two second side surfaces 122 are arranged opposite each other in the Y direction (in the middle), the area of ​​the first side surface 121 is larger than the area of ​​the second side surface 122, and the oxide aerogel sheet 13 is located between the second side surface 122 and the shell 11.

[0077] Exemplarily, the electric cell assembly 12 is in a flat body shape or a cuboid shape, and the first side surface 121 and the second side surface 122 are arranged on the circumferential direction of the electric cell assembly 12. The first side surface 121 and the second side surface 122 are connected on the circumferential direction of the electric cell assembly 12. The first side surface 121 is connected with another first side surface 121. The other first side surface 121 is connected with another second side surface 122. The other second side surface 122 is connected with the first side surface 121. The area of the first side surface 121 is greater than the area of the second side surface 122. For the electric cell assembly 12, the first side surface 121 is a large side surface of the electric cell assembly 12, and the second side surface 122 is a small side surface of the electric cell assembly 12.

[0078] When the thermal runaway of the lithium metal battery cell 10 is found, the lithium metal liquid flow spouted from the electric cell assembly 12 is easy to be spouted from the second side surface 122, which is easy to cause the rupture of the shell 11 corresponding to the second side surface 122. Therefore, the oxide aerogel sheet 13 is arranged between the second side surface 122 and the shell 11, which can correspondingly resist the lithium metal liquid flow.

[0079] In the embodiment, the oxide aerogel sheet 13 is arranged between the second side surface 122 and the shell 11. When the thermal runaway of the lithium metal battery cell 10 is found, the lithium metal liquid flow spouted from the electric cell assembly 12 is easy to be spouted from the second side surface 122. Therefore, the oxide aerogel sheet 13 arranged between the second side surface 122 and the shell 11 can correspondingly resist the lithium metal liquid flow.

[0080] In some embodiments, referring to Figures 5-6 In the projection plane perpendicular to the second side surface 122, the projection plane of the oxide aerogel sheet 13 is located in the projection plane of the second side surface 122.

[0081] Exemplarily, the area of the second side surface 122 is greater than the area of the oxide aerogel sheet 13. When the oxide aerogel sheet 13 is arranged between the shell 11 and the second side surface 122, the oxide aerogel sheet 13 is not easy to stretch out from the second side surface 122, which avoids the interference with the installation of the shell 11.

[0082] For example, the size of the first side surface 121 is 9cm*2.8cm, and the size of the oxide aerogel sheet 13 is 8.8cm*2.8cm.

[0083] In the embodiment, the area of the second side surface 122 is greater than the area of the oxide aerogel sheet 13. When the oxide aerogel sheet 13 is arranged between the shell 11 and the second side surface 122, the oxide aerogel sheet 13 is not easy to stretch out from the second side surface 122, which avoids the interference with the installation of the shell 11.

[0084] In some embodiments, referring to Figures 5-6The space between the battery cell assembly 12 and the shell 11 has a distance D1, and the thickness of the oxide aerogel sheet 13 is D2, and D2≤1 / 2D1 is satisfied.

[0085] For example, the distance between the battery cell assembly 12 and the shell 11 is 1.8 mm, 2 mm, or 2.2 mm, and the thickness of the oxide aerogel sheet 13 can be 0.9 mm, 1 mm, or 1.1 mm.

[0086] For example, the distance between the battery cell assembly 12 and the shell 11 is 1.8 mm, 2 mm, or 2.2 mm, and the thickness of the oxide aerogel sheet 13 can be 0.9 mm, 1 mm, or 1.1 mm.

[0087] The thickness of the oxide aerogel sheet 13 is less than or equal to half the distance between the battery cell assembly 12 and the shell 11, which can ensure that the battery cell assembly 12 and the shell 11 will not squeeze the oxide aerogel sheet 13, and the oxide aerogel sheet 13 will not occupy the space between the battery cell assembly 12 and the shell 11, and the space between the battery cell assembly 12 and the shell 11 is reasonably utilized.

[0088] In some embodiments, referring to Figures 5-6 In the direction from the battery cell assembly 12 to the shell 11, the oxide aerogel sheet 13 has a first part and a second part, the first part is adjacent to the battery cell assembly 12, and the second part is adjacent to the shell 11, and the content of the oxide in the first part is greater than the content of the oxide in the second part.

[0089] For example, the oxide is SiO2, and the content of SiO2 in the oxide aerogel sheet 13 close to the battery cell assembly 12 is greater than the content of SiO2 in the oxide aerogel sheet 13 close to the shell 11. When the lithium metal battery monomer 10 is in thermal runaway, the lithium metal flow first impacts the first part of the oxide aerogel sheet 13, and the content of SiO2 in the first part is greater than the content of SiO2 in the second part, which will have more SiO2 react with lithium elements in the lithium metal flow, thereby absorbing more lithium elements for further reducing the impact force of the lithium metal flow on the shell 11; compared to designing the content of SiO2 in the entire oxide aerogel sheet 13 to be equal to the content of SiO2 in the first part, the cost of the oxide aerogel sheet 13 can be reduced.

[0090] For example, the SiO2 content of the oxide aerogel sheet 13 is designed to be gradiently changed, and the SiO2 content of the oxide aerogel sheet 13 gradually decreases in the direction from the first portion to the second portion, the SiO2 content of the first portion is between 60% and 100%, and the SiO2 content of the second portion is between 0% and 40%.

[0091] In this embodiment, the oxide aerogel sheet 13 is provided with a first portion and a second portion arranged oppositely, the first portion is arranged adjacent to the cell assembly 12, and the second portion is arranged adjacent to the shell 11, the oxide content of the first portion is greater than that of the second portion, and when the lithium metal battery monomer 10 occurs thermal runaway, the oxide with a larger content in the first portion reacts with lithium elements in the lithium metal flow, thereby further reducing the impact force of the lithium metal flow on the shell 11.

[0092] In some embodiments, referring to Figures 5-6 The oxide aerogel sheet 13 has a first end and a second end arranged oppositely in the direction from the cell assembly 12 to the shell 11, the first end is arranged adjacent to the cell assembly 12, and the second end is arranged adjacent to the shell 11, and the oxide aerogel sheet 13 is provided with a plurality of pores, and the diameter of the pores gradually decreases in the direction from the first end to the second end.

[0093] For example, the arrangement of the pores does not affect the effective exhaust inside the cell assembly 12, and the diameter of the pores is designed to be gradiently changed in the direction from the first end to the second end, and the multi-stage pore design enhances the capillary effect and reduces the corrosion pressure of the metal flow on the high-temperature-resistant layer.

[0094] In addition, when the lithium metal battery monomer 10 occurs thermal runaway, the lithium metal flow first impacts the first end, the larger the diameter of the pores, the greater the contact area between the lithium metal flow and SiO2, and then more lithium elements react with SiO2 to further reduce the impact force of the lithium metal flow on the shell 11. The diameter of the pores at the second end is smaller, which can play a better supporting role.

[0095] In this embodiment, the diameter of the pores gradually decreases, and the multi-stage pore design enhances the capillary effect and reduces the corrosion pressure of the metal flow on the high-temperature-resistant layer.

[0096] In some embodiments, referring to Figures 5-6 The diameter of the pores at the first end is 20 nm to 50 nm, and the diameter of the pores at the second end is less than 20 nm.

[0097] For example, the size of the pores at the first end and the second end is reasonably arranged, so that the diameter of the pores at the first end and the second end is not too large, and the supporting property of the oxide aerogel sheet 13 is not poor.

[0098] For example, the diameter of the pores at the first end is 20 nm, 30 nm, 40 nm, or 50 nm, and the diameter of the pores at the second end is 10 nm, 13 nm, 15 nm, or 19 nm.

[0099] In this embodiment, the diameter of the pores at the first end is 20 nm to 50 nm, and the diameter of the pores at the second end is less than 20 nm. The sizes of the pores at the first end and the second end are reasonably arranged, so that the oxide aerogel sheet 13 has good supporting performance.

[0100] In some embodiments, referring to Figures 5-6 , the lithium metal battery cell 10 further includes a protective film wrapped around the outer circumferential side of the oxide aerogel sheet 13.

[0101] For example, the oxide aerogel sheet 13 is integrally formed from SiO2. Due to the characteristics of SiO2, when the oxide aerogel sheet 13 is formed, debris is likely to be generated on the outer circumferential side of the oxide aerogel sheet 13 and fall off from the oxide aerogel sheet 13. A protective film is arranged around the outer circumferential side of the oxide aerogel sheet 13 to prevent the debris from falling off from the oxide aerogel sheet 13.

[0102] For example, the protective film can be an integral piece processed from plastic or rubber.

[0103] In this embodiment, the protective film is arranged around the outer circumferential side of the oxide aerogel sheet 13 to prevent the debris remaining on the outer circumferential side of the oxide aerogel sheet 13 from falling off from the oxide aerogel sheet 13.

[0104] In some embodiments, the oxide in the oxide aerogel sheet 13 is SiO2, Al2O3, or MgO.

[0105] In this embodiment, the oxide aerogel sheet 13 formed by different oxides can be flexibly configured to have different properties according to actual needs, thereby meeting different needs. Moreover, the oxide aerogel sheets 13 formed by different oxides can effectively react with lithium elements in the lithium metal liquid stream flowing toward the shell 11 while blocking the lithium metal liquid stream, so as to hinder the erosion of the lithium elements on the shell 11.

[0106] In some embodiments, referring to Figures 5-6 , the oxide aerogel sheet 13 includes a SiO2 aerogel sheet.

[0107] In this embodiment, the oxide aerogel sheet 13 includes a SiO2 aerogel sheet, and the oxide aerogel sheet has good heat insulation effect.

[0108] In some embodiments, the oxide aerogel sheet 13 comprises a fumed SiO2 sheet, and the density of the fumed SiO2 sheet is greater than the density of the SiO2 aerogel sheet.

[0109] In this embodiment, the oxide aerogel sheet 13 comprises a fumed SiO2 sheet, and the oxide aerogel sheet has good heat insulation effect.

[0110] For example, the SiO2 content of the fumed SiO2 sheet is greater than the SiO2 content of the SiO2 aerogel sheet, and the heat insulation effect of the fumed SiO2 sheet is higher than the heat insulation effect of the SiO2 aerogel sheet.

[0111] The fumed SiO2 sheet is processed by a fumed method, and the SiO2 aerogel sheet is prepared by a sol-gel method + drying process.

[0112] For example, the SiO2 aerogel sheet has a density of about 0.003-0.1 g / cm3, and the fumed SiO2 sheet has a density of about 0.05-0.2 g / cm3.

[0113] Example 1: The cell assembly 12 uses a 73Ah NCM|Cu-Li hard shell cell, and the shell 11 is a stainless steel shell. The size of the side shell 11 corresponding to the first side 121 of the cell assembly 12 is 9cm *2.8cm. A SiO2 aerogel sheet with a size of 8.8mm *2.8mm *1mm is inserted between the first side 121 and the side shell 11. The built-in heating film is triggered, and the damage of the shell 11 is observed after thermal runaway.

[0114] Example 2: A fumed SiO2 sheet with a size of 8.8mm *2.8mm *1mm is inserted between the first side 121 and the side shell 11. The other aspects are the same as those in Example 1.

[0115] Comparative Example 1: No additional protective pad is added to the side of the cell assembly 12. The triggering method is consistent with that of Example 1.

[0116]

[0117] Example 1 and Example 2 compared with Comparative Example 1 show that the oxide aerogel sheet 13 on the side can effectively reduce the impact of the metal liquid flow on the side and reduce the pressure on the side shell 11.

[0118] Example 1 and Example 2 show that for a 73Ah lithium metal system, the fumed SiO2 sheet with a higher SiO2 content has a better effect on absorbing the metal liquid flow than the SiO2 aerogel sheet.

[0119] The battery device 101 according to the second aspect of the present application comprises the lithium metal battery monomer 10 according to the first aspect of the present application.

[0120] According to the power utilization device, the performance of the battery device 101 is improved, and thus the working power utilization performance of the power utilization device is improved.

[0121] According to the power utilization device of the third aspect of the present application, the battery device 101 of the second aspect of the present application is included.

[0122] According to the power utilization device, the performance of the battery device 101 is improved, and thus the working power utilization performance of the power utilization device is improved.

[0123] The lithium metal battery cell 10 according to an embodiment of the present application will be described below. Figures 1-6 The lithium metal battery cell 10 according to an embodiment of the present application will be described below.

[0124] The lithium metal battery cell 10 includes a shell 11 and an electrode assembly 12, the electrode assembly 12 is located in the shell 11, an oxide aerogel sheet 13 is arranged between the shell 11 and the electrode assembly 12, a protective film is arranged on the outer circumferential side of the oxide aerogel sheet 13, and a spacing space is arranged between the electrode assembly 12 and the shell 11, the distance of the spacing space is D1, the thickness of the oxide aerogel sheet 13 is D2, and D2≤1 / 2D1.

[0125] The electrode assembly 12 has a first side surface 121 arranged opposite in a first direction and a second side surface 122 arranged opposite in a second direction, the area of the first side surface 121 is greater than the area of the second side surface 122, and the oxide aerogel sheet 13 is arranged between the second side surface 122 and the shell 11. In the direction from the electrode assembly 12 to the shell 11, the oxide aerogel sheet 13 has a first part and a second part arranged opposite, the first part is arranged adjacent to the electrode assembly 12, the second part is arranged adjacent to the shell 11, and the content of SiO2 in the first part is greater than the content of SiO2 in the second part.

[0126] In the direction from the electrode assembly 12 to the shell 11, the oxide aerogel sheet 13 has a first end and a second end arranged opposite, the first end is arranged adjacent to the electrode assembly 12, the second end is arranged adjacent to the shell 11, the oxide aerogel sheet 13 is provided with a plurality of pores, and in the direction from the first end to the second end, the diameter of the pores gradually decreases; the diameter of the pores at the first end is 20nm-50nm, and the diameter of the pores at the second end is less than 20nm.

[0127] In the description of the application, it needs to be understood that the terms "upper", "lower", "front", "back", "left", "right" and the like indicate the orientation or positional relationship shown in the drawings based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the application. In addition, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first", "second" can explicitly or implicitly include one or more of the features. In the description of the application, the meaning of "a plurality of" is two or more, unless otherwise explicitly specified and limited.

[0128] In the description of the application, it needs to be explained that, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integral connection; it can be mechanical connection, or electrical connection; it can be direct connection, or indirect connection through intermediate medium, it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the application can be understood according to the specific circumstances.

[0129] In the description of the specification, the description referring to the terms "some embodiments", "optionally", "further", or "some examples" and the like means that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the application. In the specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0130] Although the embodiments of the application have been shown and described, those skilled in the art can understand that various changes, modifications, replacements and variations can be made to the embodiments without departing from the principles and purposes of the application, and the scope of the application is defined by the claims and their equivalents.

Claims

1. A lithium metal battery cell, characterized in that, Comprising: a shell (11); an electric core assembly (12) located in the shell (11), the electric core assembly (12) comprising a lithium metal negative electrode and a positive electrode arranged in a stack; an oxide aerogel sheet (13) located between the shell (11) and the electric core assembly (12) and along a preset direction, at least part of the positive projection of the oxide aerogel sheet (13) on the electric core assembly (12) covering the electric core assembly (12); wherein the preset direction is at least one of the height direction, the length direction or the width direction of the electric core assembly (12).

2. The lithium metal battery cell of claim 1, wherein, The electric core assembly (12) has a first side (121) and a second side (122), the area of the first side (121) being greater than the area of the second side (122), and the oxide aerogel sheet (13) is located between the second side (122) and the shell (11).

3. The lithium metal battery cell of claim 2, wherein, In the projection plane perpendicular to the second side (122), the projection plane of the oxide aerogel sheet (13) is located in the projection plane of the second side (122).

4. The lithium metal battery cell of claim 1, wherein, The electric core assembly (12) and the shell (11) have a spacing space, along the thickness direction of the oxide aerogel sheet (13), the distance of the spacing space is D1, and the thickness of the oxide aerogel sheet (13) is D2, satisfying: D2≤1 / 2D1.

5. The lithium metal battery cell of claim 1, wherein, In the direction from the electric core assembly (12) to the shell (11), the oxide aerogel sheet (13) has a first part and a second part, the first part is arranged adjacent to the electric core assembly (12), and the second part is arranged adjacent to the shell (11), the content of oxide of the first part being greater than the content of oxide of the second part.

6. The lithium metal battery cell of claim 1, wherein, The oxide aerogel sheet (13) has a plurality of pores, and in the direction from the electric core assembly (12) to the shell (11), the diameter of the pores gradually decreases.

7. The lithium metal battery cell of claim 6, wherein, The diameter of the pores near the electric core assembly (12) is 20-50 nm, and the diameter of the pores near the shell (11) is less than 20 nm.

8. The lithium metal battery cell of claim 1, wherein, Further comprising: a protective film wrapped around the outer periphery of the oxide aerogel sheet (13).

9. The lithium metal battery cell of claim 1, wherein, The oxide of the oxide aerogel sheet (13) is SiO2, Al2O3 or MgO.

10. The lithium metal battery cell of claim 1, wherein, The oxide aerogel sheet (13) comprises a SiO2 aerogel sheet.

11. The lithium metal battery cell of claim 1, wherein, The oxide aerogel sheet (13) comprises a fumed SiO2 sheet.

12. A battery device characterized by comprising: Comprising: The lithium metal battery cell of any one of claims 1-11.

13. An electrical device, comprising: Comprising: The battery device of claim 12.

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