Lithium battery thermal runaway suppression assembly and applications thereof

Abstract

The present application provides a lithium battery thermal runaway inhibition assembly and its application. The lithium battery thermal runaway inhibition assembly comprises a composite salt layer with a melting temperature of 90-150°C, which is formed by the eutectic of at least two or more inorganic single salts, and the cation of at least one of the inorganic single salts is an alkali metal cation or an amphoteric element cation. The lithium battery thermal runaway inhibition assembly is arranged on the outside or inside of the lithium battery. When the lithium battery generates heat and the temperature rises to 90-150°C, the composite salt layer melts into a liquid state and reacts with the electrochemical reaction system of the lithium battery, so that the active material becomes passive and the ion and electron movement ability decreases, thereby terminating the battery thermal runaway and the related problems derived therefrom.

Description

Technical Field

[0001] This invention relates to a battery safety mechanism, and more particularly to a lithium battery thermal runaway suppression component and its application. Background Technology

[0002] Lithium batteries, such as lithium rechargeable batteries, are widely used in various products, such as transportation vehicles, wearable products for consumer and industrial applications, portable devices and energy storage devices, etc., almost covering all aspects of people's daily lives. However, lithium battery accidents are frequently reported, such as fires and explosions of mobile phone batteries and electric vehicles. These are all because there is still a lack of comprehensive and effective solutions to the safety issues of lithium batteries.

[0003] The primary cause of lithium battery fires and explosions is thermal runaway, which is mainly caused by heat—specifically, the exothermic reaction resulting from the gradual thermal decomposition of various substances within the battery, including the SEI film, electrolyte, binder, and positive and negative electrode active materials. Currently, methods to suppress thermal runaway can be categorized into two types based on the location of the safety mechanism reaction: outside the cell and inside the cell. External methods primarily utilize digital simulation monitoring systems, while internal methods can be further divided into physical and chemical approaches. External digital monitoring systems employ various technologies, such as dedicated protection circuits and management systems, to enhance safety monitoring during battery use. Physical methods within the cell include thermal shutdown separators, which seal the pores of the separator when the battery cell overheats abnormally, blocking ion passage. Chemical methods within the cell can be categorized into degree-control types and electrochemical reaction types. Degree-control types include adding flame retardants to the electrolyte to control the degree of thermal runaway. Examples of electrochemical reaction types include: 1. Adding monomers or oligomers to the electrolyte causes polymerization as the temperature rises, reducing ion migration and decreasing ionic conductivity with increasing temperature, thus slowing down the electrochemical reaction rate within the battery cell. 2. Sandwiching a positive temperature coefficient thermistor (PTC) material between the positive or negative electrode layer and the adjacent current collector layer. As the cell temperature rises, the electronic insulation capability increases, reducing the electron transfer capability between the positive or negative electrode layer and the adjacent current collector layer, thereby slowing down the electrochemical reaction rate. 3. Forming a modification layer on the surface of the positive electrode active material. At high temperatures, the modification layer transforms into a dense film, increasing charge transfer resistance and thus slowing down the electrochemical reaction rate.

[0004] However, the above methods mainly suppress thermal runaway in a single way, and therefore lack a high-efficiency composite thermal runaway suppression that is fast and simultaneous in multiple ways. In view of this, the present invention proposes a novel thermal runaway suppression component and its application to effectively solve the above problems. Summary of the Invention

[0005] The main objective of this invention is to provide a novel lithium-ion battery thermal runaway suppression component and its application. This component, located externally or internally to the lithium-ion battery, melts into a liquid state at 90-150°C and reacts with the components in the battery's electrochemical reaction system. This passivates the active material, making it thermodynamically stable, such as inactive or passive, thus reducing its high heat release capacity. The molten thermal runaway suppression component etches the aluminum current collector layer to lower the state of charge (SOC). Throughout the reaction, the molten thermal runaway suppression component simultaneously contaminates or passivates the surfaces of the active material and the solid electrolyte, reducing ionic and electronic conductivity. It also polymerizes and carbonizes the liquid / gel / gel electrolyte, hindering ion movement, thereby achieving multi-directional and simultaneous effective termination of battery thermal runaway and its related problems.

[0006] To achieve the above objectives, the present invention provides a lithium battery thermal runaway suppression component, which is added to a lithium battery capable of charging and discharging. The lithium battery thermal runaway suppression component includes a composite salt layer, which is formed by the co-melting of at least two or more inorganic single salts. The melting temperature of the composite salt layer is 90-150°C. At least one of the inorganic single salts has an alkali metal cation or an amphoteric element cation as its cation, and the inorganic single salt has an inorganic anion as its anion.

[0007] The present invention also provides a lithium battery with a thermal runaway suppression component, comprising an encapsulation component; an electrochemical reaction system disposed within the encapsulation component; and a lithium battery thermal runaway suppression component disposed outside or within the encapsulation component, comprising a composite salt layer formed by the co-melting of at least two or more inorganic single salts, the melting temperature of the composite salt layer being 90-150°C, wherein at least one of the inorganic single salts has a cation that is an alkali metal cation or an amphoteric element cation, and the anions of the inorganic single salts are inorganic anions.

[0008] The following detailed description through specific embodiments will make it easier to understand the purpose, technical content, features and effects achieved by the present invention. Attached Figure Description

[0009] Figures 1A-1B This is a schematic diagram of the structure of the passivated positive electrode active material powder.

[0010] Figure 1C This is a schematic diagram of the negative end structure after passivation.

[0011] Figures 2A-2D This is a schematic diagram of various embodiments of the thermal runaway suppression component of the present invention.

[0012] Figures 3-7 These are schematic diagrams of various embodiments incorporating the thermal runaway suppression component of the present invention.

[0013] Figure 8 This is a schematic diagram of another embodiment of the thermal runaway suppression component of the present invention.

[0014] Figures 9-15 These are schematic diagrams of various embodiments incorporating the thermal runaway suppression component of the present invention.

[0015] Figure Labels

[0016] 10 Thermal runaway suppression components

[0017] 13 substrates

[0018] 14 powder

[0019] 15 composite salt layers

[0020] 16 Adhesive

[0021] 17 Spherical Structure

[0022] 18 holes

[0023] 19 protective layers

[0024] 20 Lithium Battery

[0025] 22 through holes

[0026] 24 Electrochemical Reaction System

[0027] 241 Positive Electrode Active Material

[0028] 242 isolation layers

[0029] 243 Anode Active Material

[0030] 26 First collector layer

[0031] 28 Second collector layer

[0032] 29 Frame

[0033] 30-wound lithium battery

[0034] 31 gate layers

[0035] 32 bumps

[0036] 33 protective layers

[0037] 34U-shaped metal sheet

[0038] 341 Parallel sidewalls

[0039] 342 Connecting part

[0040] 343 storage space

[0041] 35 Electrochemical Reaction System

[0042] 36 Etching Direction Confinement Layer

[0043] 37 package housing

[0044] 38 grooves

[0045] 39 bumps

[0046] 41 Etching Auxiliary Cutting Line

[0047] 50 Passivation active material powder

[0048] 51 passivation layer structure

[0049] 52 Active Material Powder

[0050] 53 Lithium-containing compound layers

[0051] 54 negative extremes

[0052] 55 negative electrode passivation layer

[0053] 56-core layer Detailed Implementation

[0054] To make the advantages, spirit, and features of the present invention more readily apparent, detailed descriptions and discussions will follow with examples. It should be noted that these examples are merely representative embodiments of the present invention and are not intended to limit the scope of implementation or protection of the invention to these specific examples. The purpose of providing these examples is solely to make the disclosure of the present invention more thorough and easily understood.

[0055] The terminology used in the various embodiments disclosed in this invention is for the purpose of describing particular embodiments only and is not intended to limit the various embodiments disclosed in this invention. Unless explicitly indicated otherwise, the singular forms used also include the plural forms. Unless otherwise specified, all terms used in this specification (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which the various embodiments disclosed in this invention pertain. The foregoing terms (such as those defined in general-purpose dictionaries) are to be interpreted as having the same meaning as in the context of the same technical field and are not to be interpreted as having an idealized or overly formal meaning unless explicitly defined in the various embodiments disclosed in this invention.

[0056] In the description of this specification, references to terms such as "an embodiment" or "a specific embodiment" mean that a specific feature, structure, material, or characteristic described in connection with that embodiment is included in at least one embodiment of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments.

[0057] This invention relates to a component for suppressing thermal runaway in lithium batteries, comprising a composite salt that can melt into a liquid state at 90-150°C. When the lithium battery is heated to 90-150°C, the composite salt of the lithium battery thermal runaway suppression component, which is solid and disposed inside or outside the lithium battery encapsulation assembly, will melt. This molten composite salt will have fluidity and react with some components of the electrochemical reaction system disposed within the lithium battery encapsulation assembly and capable of lithium-ion insertion and extraction (i.e., charging and discharging). The encapsulation assembly referred to here is a component that isolates the electrochemical system from the external environment. The electrochemical reaction system generally includes a positive electrode active material layer (capable of charging and discharging with lithium ions), a negative electrode active material layer (which can be lithium metal, lithium alloy, or any material that allows the inserted lithium ions to be released), an isolation layer sandwiched between the positive and negative electrode active materials, an electrolyte impregnated or filled within the positive and negative electrode active materials, and an adhesive, etc. This molten composite salt forms a positive electrode passivation layer on the surface of the active material powder at the positive electrode. For example, the reaction of the aforementioned molten composite salt with electrolytes and adhesives will form a passivation layer structure 51, similar to a shell, coating the surface of the active material powder 52 at the positive end. The active material powder 52 can be considered as a core layer. Figure 1A As shown, the shell and core layers will form a passivation active material powder 52. In this case, the core layer is essentially equivalent to the original positive electrode active material powder size. Alternatively, the passivation layer structure 51 may also include a lithium compound layer 53 formed by reacting with components in the positive electrode active material powder 52, such as... Figure 1B As shown, the remaining unreacted positive electrode active material powder 52 at this time will be regarded as the core layer 56, and the aforementioned passivation layer structure 51 can partially or completely cover the positive electrode active material powder 52. The aforementioned lithium battery is a non-waste battery and is installed on various electronic or mechanical devices to provide power to these electronic or mechanical devices.

[0058] At the negative electrode, the molten composite salt forms a stable compound with the negative electrode active material and other materials, such as electrolytes and / or adhesives, and partially or completely covers the surface of the negative electrode 54. This stable compound serves as the negative electrode passivation layer 55. Figure 1CAs shown. This negative electrode active material can be selected from lithium metal, for example, in the form of lithium foil or lithium plate, or lithium alloy, such as lithium silicon alloy, lithium tin alloy or lithium indium alloy, or any material that can release embedded lithium ions, such as carbon.

[0059] The electrolytes described above can be selected from: 1. liquid electrolytes, such as non-aqueous organic liquid electrolytes, gel electrolytes, or jelly electrolytes; 2. solid-solid mixed electrolytes formed by a single solid electrolyte or multiple solid electrolytes; or 3. mixed electrolytes formed by combining solid electrolytes with liquid / gel / jelly electrolytes. Examples of the single or multiple solid electrolytes mentioned above include oxide, sulfide, or polymer solid electrolytes, or other solid electrolytes selected individually or in combination. The oxide solid electrolytes mentioned above include phosphate series, such as lithium aluminum titanium phosphate (LATP) and LIPON (Lithium Phosphorous OxyNitride). Other solid electrolytes include nitrides, halides, or hydrides.

[0060] The composite salt layer used in this invention, upon melting, etches the aluminum current collector layer, causing a discharge effect and reducing the State of Charge (SOC). It also contaminates or passivates the surface of the active material and / or the solid electrolyte, resulting in decreased ionic and electronic conductivity and charge transfer rate. Furthermore, it polymerizes and carbonizes the liquid / colloidal / gel electrolyte, hindering ion movement. For example, components in the composite salt layer used in this invention, such as AlCl3 or LiCl, upon melting, can perform ring-opening polymerization on carbonate-based liquid electrolytes with ring-opening polymerization capabilities, such as cyclic carbonates like GBL (gamma-butyrolactone) or EC (ethylene carbonate), or fluoroethylene carbonate (FEC), etc., and break the chains of salts with O=S=O bonds in the electrolyte of the lithium battery, thereby causing carbonization of the polymer in the electrolyte. The aforementioned salts with O=S=O bonds can be selected from salts containing the following anions, such as CO2C. n F 2n+1 - SO3CnF 2n+1 - SO4(C2H4O) n CH3 - SO3(C6F5) - SO3(CF2) n SO3 2- SO3(C6F4)SO32- 、PO3(C2F 2n+1 ) 2- 、PO2(C2F 2n+1 )2 - 、BF3(SO2C n F 2n+1 ) - 、BF2(SO2C n F 2n+1 )2 - 、BF(SO2C n F 2n+1 )3 - 、B (SO2C n F 2n+1 )4 - 、BF3(PO2F2) - 、BF2(PO2F2)2 - 、BF(PO2F 3 ) - 、PF5(SO2C n F 2n+1 ) - 、PF4(SO2C n F 2n+1 )2 - 、PF3(SO2C n F 2n+1 )3 - 、PF2(SO2C n F 2n+1 )4 - 、PF(SO2C n F 2n+1 )5 - 、PF5(PO2F2) - 、PF4(PO2F2)2 - 、PF3(PO2F2)3 - 、N(COC n F 2n+1 )2 - 、N(SO2C n H 2n+1 )2 - 、N(SO2C n F 2n+1 )2 - 、N(COC n F 2n+1 )(SO2C n F 2n+1 ) - 、N(SO2C6H5)(SO2CF3) - 、N(SO2C6F5)2 - 、N(SO2C3F6SO2)- 、N(SO2C4F8SO2)-、CO(NSO2F)2 2- SO2(NSO2C) n F 2n+1 2) 2- (CF2) n (SO2NSO2CF3)2 2- N(SO2C2F4O(C2H4O)CH3)2 - N(SO2C4H8SO3)2 3- N(SO2CH2CO2)2 3- N(SO2CH2CO(C6H4)SO3)2 3- (C6H4)(SO2NSO2CF3)2 2- 、O((C6H4)SO2NSO2CF3)2 2- 、(C6H2)(OC2H2O)(SO2NSO2CF3)2 2- N(SO2NSOF2) 2- N(CONSNSO2) - N(SO2NSNSO2) - C(SO2C) n H 2n+1 3) - C(SO2C) n F 2n+1 3) - (TriTFSM - CH(SO2C) n F 2n+1 2) - SO2(NCN)2 - N(SO2C) n F 2n+1 (CN) - C(SO2C) n F 2n+1 (CN)2 - C(SO2C) n F 2n+1 2(CN) - SO2(C(CN)2)2 - N(COC) n F 2n+1 (CnF) 2n+1 ) - N(SO2C) n F 2n+1 (C) n F 2n+1 ) - N(SO2C) n F2n+1 (C6F5)-、N(SO2(CN))2 - N(PO(CN)2)2 - C(SO2C2N2S(CF3))(CN)2 - N(SO2C) n F 2n+1 (SO2CN) - 、N(PO(C n F 2n+1 )2)(PO(CN)2) - S(OCH5)(NSO2CF3)2 - 、N(C(CF3)NSO2NC(CF3)) - Al(N(SO2CF3)2)2(O(CH2(H2O)) n CH3)2 - PO(NSO2CF3)3 -3 etc.

[0061] The melting temperature of the aforementioned composite salt layer is 90-150℃. This composite salt layer is formed by the eutectic melting of two or more inorganic single salts. The cation portion of these inorganic single salts is preferably selected from alkali metal cations or amphoteric element cations, but is not limited to alkali metal cations or amphoteric element cations; for example, it can also be iron ions. The anionic portion is an inorganic anion. For example, any inorganic single salt constituting the composite salt layer can be selected from the following materials: LiNO3, AlCl3, NaCl, KCl, LiCl, AlBr2, Ca(NO3)2, NaNO3, KNO3, ZnCl4, FeCl3, FeBr3, etc. For example, AlCl3:NaCl:KCl in a ratio of 61:26:13 can be eutecticly mixed to form the composite salt layer. Alternatively, AlCl3:NaCl:KCl in a ratio of 59:29:12 can be eutecticly mixed. Alternatively, AlCl3:NaCl:KCl can be eutecticly mixed in a ratio of 75:16:9. Or, AlCl3:NaCl:KCl:LiCl can be eutecticly mixed in a ratio of 76:11:5:8. Or, NaNO3:KNO3:LiNO3:Ca(NO3)2 can be eutecticly mixed in a ratio of 25:45:5:25. Or, NaNO3:KNO3:LiNO3:Ca(NO3)2 can be eutecticly mixed in a ratio of 65:5:5:25. Or, NaNO3:KNO3:LiNO3:Ca(NO3)2 can be eutecticly mixed in a ratio of 45:25:5:25.

[0062] In addition, to accelerate the melting of the composite salt layer, organic salts can be added, such as tetrabutylammonium chloride (70°C), chlorinated (1-butyl-3-methylimidazolium); chlorinated (1-ethyl-3-methylimidazolium); chlorinated (84°C), tetrabutylammonium bromide (103°C), hexadecyltributylphosphine bromide (89°C), etc.

[0063] Please see Figures 2A-2D This is a schematic diagram of various embodiments of the thermal runaway suppression component of the present invention. As shown in the figure, the main body of the thermal runaway suppression component 10 of the present invention is a composite salt layer 15 formed by the co-melting of two or more inorganic single salts with different melting temperatures. This composite salt layer 15 can be formed by coating these inorganic single salts onto the surface of a substrate 13 after co-melting, followed by cooling. Figure 2A As shown. Alternatively, a composite salt layer 15 is formed by co-melting and cooling two or more inorganic single salts with different melting temperatures, grinding them into powder 14, and then coating them onto a substrate 13 using a solvent-free film-forming adhesive 16. Figure 2B As shown. Alternatively, electrostatic spraying can be used to fix multiple powders 14 to the surface of the substrate 13 due to electrostatic attraction, in which case the powders themselves also attract each other. Electrostatic spraying can also use an adhesive, but this adhesive must be a dry, solvent-free type and only require high temperature to produce adhesion. The substrate 13 mentioned above can also be a removable temporary substrate (dummy) or directly the surface of the component to which the thermal runaway suppression component 10 is to be installed. The solvent-free film-forming adhesive 16 mentioned above can be made of polyacrylate latex, polyethylene oxide (PEO) series, or polyethylene glycol diacrylate (PEGDA) series. The film-forming adhesive 16 mentioned above can be selected from thermoplastic materials, thermosetting materials, or liquid metals with low melting points relative to non-liquid metals, etc.

[0064] The substrate 13 can be composed of a passive material that does not react with the molten composite salt layer 15, such as a copper sheet or a glass sheet. Furthermore, the substrate 13 can be non-porous or porous (with holes 18), such as… Figure 2C As shown, when the substrate 13 has pores 18, it can serve as a guiding layer to guide the flow of the molten composite salt layer 15. This substrate 13 with pores 18 can be formed by stacking metal oxide particles that do not react with the molten composite salt layer using an adhesive, or it can be woven from glass fibers. Furthermore, as... Figure 2DAs shown, the thermal runaway suppression component 10 of the present invention can also be formed by injecting a variety of inorganic single salts into a substrate 13 with pores 18 after co-melting, and then cooling. At this time, the composite salt layer 15 will be embedded in the pores 18 of the substrate 13, or the substrate 13 can be embedded in the composite salt layer 15.

[0065] Next, the aforementioned lithium battery thermal runaway suppression component 10 is integrated into a lithium battery to form a lithium battery safety mechanism. The lithium battery thermal runaway suppression component 10 can be disposed inside or outside the lithium battery's encapsulation assembly. When the lithium battery thermal runaway suppression component 10 is disposed outside the lithium battery's encapsulation assembly, the encapsulation assembly must have at least one through-hole when the lithium battery temperature reaches 90-150°C to allow the thermal runaway suppression component 10 to melt into the lithium battery. One end of the through-hole is connected to the lithium battery thermal runaway suppression component 10, and the other end is connected to the lithium battery's electrochemical reaction system. For example, this through-hole may be formed by the gas generated by the chain reaction triggered by temperature in the lithium battery damaging the encapsulation assembly, or it may be intentionally pre-designed to be formed on the encapsulation assembly, or it may be formed by the etching of the encapsulation assembly by components in the composite salt layer, or it may be caused by puncture by an external sharp object.

[0066] The following embodiments are described based on the above description, but are not limited to the following embodiments.

[0067] First embodiment: Please refer to Figure 3 The lithium battery 20 has at least one through-hole 22, one end of which is exposed to the external environment of the lithium battery 20, and the other end is connected to the electrochemical reaction system 24 (positive electrode active material 241 / isolation layer 242 / negative electrode active material 243) inside the lithium battery 20. The lithium battery thermal runaway component 10 covers one end of the through-hole 22, so that the through-hole 22 can be connected to the lithium battery thermal runaway component 10. When the temperature of the lithium battery 20 rises to 90-150°C, the composite salt layer 15 will melt and penetrate into the electrochemical reaction system 24 of the lithium battery 20 through the through-hole 22 to react with the positive and negative electrode active materials, coating the particle surface of the positive electrode active material layer 241 and the surface of the negative electrode active material layer 243, thereby terminating the electrochemical reaction of the lithium battery 20. The aforementioned thermal runaway suppression component 10 can be directly disposed on the outer surface of the first current collector layer 26 of the lithium battery 20, as shown in the figure. The first current collector layer 26 has a plurality of tiny through holes 22, the size of which ranges from 1 micrometer to 15 micrometers.

[0068] Under the above architecture, because the thermal runaway suppression component 10 of the present invention is disposed outside the packaging component of the lithium battery 20, it will not affect the efficiency or composition of the electrochemical reaction system of the lithium battery. Furthermore, Figure 3The lithium battery 20 includes a first current collector layer 26 and a second current collector layer 28, a frame 29 sandwiched between the first current collector layer 26 and the second current collector layer 28 with one end attached to the first current collector layer 26 and the other end attached to the second current collector layer 28. The first current collector layer 26, the second current collector layer 28 and the frame 29 form a sealed enclosed space (ignoring the perforation 22), and an electrochemical reaction system 24 disposed within this enclosed space. The electrochemical reaction system 24 includes a positive electrode active material 241 adjacent to the first current collector layer 26 and a negative electrode active material 243 adjacent to the second current collector layer 28, a separator 242 located between the positive electrode active material 241 and the negative electrode active material 243, which has ion conduction and electronic insulation properties, and an electrolyte system located within the enclosed space and impregnated / contacting the positive electrode active material 241 and the negative electrode active material 243 for ion transfer. Of course, the positive electrode active material 241 and the negative electrode active material 243 mentioned above each have conductive materials and adhesive materials, but since these parts are not the focus of this invention, they will not be described in detail here.

[0069] Furthermore, the aforementioned isolation layer 242 may be composed of a polymer solid electrolyte, or it may be a porous electronic insulating layer formed of a polymer material with a surface coated with ceramic powder. Alternatively, the isolation layer 242 may be formed solely from ceramic powder stacked using an adhesive. This ceramic powder may be in a passive state without ionic conductivity, or it may be in a non-passive state with ionic conductivity.

[0070] exist Figure 3 In the embodiment described, the first current collector layer 26, the second current collector layer 28, and the encapsulation frame 29 serve as the encapsulation components for this lithium battery 20. That is, ignoring the through-hole 22, the electrochemical reaction system 24 of this lithium battery 20 is isolated from the external environment under the protection of this encapsulation component. The encapsulation frame 29 is made of a polymer material; there are no particular material limitations as long as it can adhere to the surfaces of the first and second current collector layers 26 and 28 and is durable for the electrolyte system, but thermosetting resins are preferred, such as silicone.

[0071] Furthermore, to prevent the thermal runaway suppression component 10 and the electrochemical reaction system from interfering with each other due to the pre-formed through-hole 22, a removable gate layer 31 can be provided at the opening end of the through-hole 22 on the outer surface of the first current collector layer 26 to temporarily seal the through-hole 22, such as... Figure 4As shown. The gate layer 31 is made of a material with excellent resistance to the electrolyte system. This gate layer 31 will decompose at around 90-110°C, forming several pores, allowing the molten composite salt layer 15 to enter the electrochemical reaction system of the lithium battery 20 through the pores. When the decomposition temperature is not reached, the presence of the gate layer 31 can prevent the electrolyte from damaging the thermal runaway suppression component 10. For example, the material constituting the gate layer 31 can be a silicone polymer, which can undergo a depolymerization reaction with the molten composite salt layer 15 of the thermal runaway suppression component 10. That is, the gate layer 31 will not only decompose due to temperature, but also depolymerize due to the melting of the composite salt layer 15, thus accelerating the formation of pores in the gate layer 31.

[0072] Furthermore, the thermal runaway suppression component 10 of the present invention can also be sandwiched between two lithium batteries 20, such as... Figure 5 The state is shown. The two vertically stacked lithium batteries 20 described above can be electrically connected via tabs. Please refer to... Figure 6 This is another architecture for the lithium battery with thermal runaway suppression component 10 of the present invention. In this embodiment, several bumps 32 are formed on the open side surface of the first current collector layer 26. The material of the bumps 32 can be selected from a passive metal, glass, or polymer that does not react with the composite salt layer 15. Several grooves are formed on the surface of the first current collector layer 26 exposed outside the bumps 32. The grooves cover at least one through hole 22. The gate layer 31 and the thermal runaway suppression component 10 located outside the gate layer 31 are sequentially filled in the grooves. The bumps 32 are less sensitive to changes in the external environment than the composite salt layer 15 in the thermal runaway suppression component. The changes in the external environment can be changes in temperature, pH value, or electrolyte concentration. For example, when the external environmental condition is temperature, under this architecture, the composite salt layer 15 in the thermal runaway suppression component 10 will melt first because it is more sensitive to temperature changes than the bump 32. At this time, since the bump 32 is not destroyed, it can more effectively limit the direction of the movement of the relevant ions released by the thermal runaway suppression component 10 to the gate layer 31 and the first collector layer 26, thereby avoiding the generation of ineffective overflow.

[0073] When applied to wound lithium batteries, angular lithium batteries, or aluminum-clad lithium batteries, the thermal runaway suppression component 10 of the present invention can be disposed between the encapsulation housing and the electrochemical reaction system. For example, such as Figure 7 As shown, the thermal runaway suppression component 10 of the present invention can be disposed in the space between the encapsulation housing 37 of the wound lithium battery 30 and the electrochemical reaction system 35. In addition, in order to avoid mutual interference between the electrochemical reaction system and the thermal runaway suppression component 10 of the present invention, a protective layer 33 can be completely covered on the outer surface of the thermal runaway suppression component 10. The material of the protective layer 33 can be selected from a thermosensitive decomposition material, or the same as the material of the gate layer 31 described above.

[0074] In addition to the above-described embodiment of the sheet-like thermal runaway suppression component 10 (see...), Figures 2A-2D Alternatively, the composite salt after co-melting and cooling can be formed into a spherical structure 17, and a protective layer 19 can be formed on the outer surface of the spherical structure 17, such as... Figure 8 As shown. The material of this protective layer 19 can be selected from thermoplastic materials that melt at high temperatures, thermosetting materials that depolymerize at high temperatures, such as silicone, silicone molecules, or liquid metals that melt at low temperatures. In this embodiment, the spherical thermal runaway suppression component 10 can be directly added to the positive electrode active material, negative electrode active material, or electrolyte of various lithium battery types. The various lithium battery types mentioned above also include lithium battery types that use a current collector layer and a frame as the encapsulation structure as described earlier in this application, such as... Figure 3 The shape is as shown, but without the need for perforation. Furthermore, the spherical structure 17 may also contain a material capable of absorbing molten composite salts, such as glass fiber.

[0075] The following lithium battery embodiment with thermal runaway suppression utilizes the etching characteristics of the composite salt layer of the thermal runaway suppression component 10 on the current collector layer made of aluminum when it is in a molten state to enable the composite salt layer in the molten state to penetrate from the outside of the lithium battery into the electrochemical reaction system to passivate the positive and negative electrode active materials.

[0076] Please see Figure 9 The thermal runaway suppression component 10 of the present invention is disposed on the outer surface of the first current collector layer 26 of a lithium battery 20, and the first current collector layer 26 is made of aluminum. Therefore, when the lithium battery 20, which uses the current collector layer as a packaging component, is heated to 90-150°C, the composite salt in the thermal runaway suppression component 10 will melt and etch the first current collector layer 26. After etching through, the composite salt will coat the surface of the positive electrode active material particles to form a passivation layer, or / and form a passivation layer on the surface of the negative electrode active material layer, and simultaneously perform etching, passivation, or polymerization reactions such as reducing electronic and ion conductivity as previously described. In addition, as Figure 10 As shown, the thermal runaway suppression component 10 of the present invention can also be sandwiched between two lithium batteries 20. Please refer to... Figure 11As shown, when two stacked lithium batteries 20 are connected in series, a U-shaped metal sheet 34 can be sandwiched between the two lithium batteries 20. The material of this U-shaped metal sheet 34 can be a material that can be etched by the thermal runaway suppression component 10 or a mesh metal. This U-shaped metal sheet 34 includes two parallel sidewalls 341 and a connecting portion 342 connecting the two parallel sidewalls 341, as well as an accommodating space 343 located between the two parallel sidewalls 341 and the connecting portion 342. The thermal runaway suppression component 10 is sandwiched in the accommodating space 343 in the middle of the U-shaped metal sheet 34. One parallel sidewall 341 is attached to the first current collector layer 26 of the lithium battery 20, and the other parallel sidewall 341 is attached to the second current collector layer 28 of the other lithium battery 20 to facilitate electrical conduction between the two adjacent lithium batteries 20.

[0077] Or, such as Figure 12 As shown, an etching direction confinement layer 36 is also circumferentially disposed around the sidewall of the thermal runaway suppression component 10. The etching direction confinement layer 36 is less sensitive to changes in the external environment than the thermal runaway suppression component 10. The two end faces of this etching direction confinement layer 36 can be adjacent to or connected to the first current collector layer 26 and the second current collector layer 28 of the upper and lower lithium battery 20, respectively. The aforementioned external environmental changes can be variations in temperature, pH, or electrolyte concentration. For example, when the external environmental change is temperature, under this architecture, the composite salt layer 15 of the thermal runaway termination component 10 will melt first compared to the etching direction confinement layer 36. Since the circumferential etching direction confinement layer 36 is not destroyed, it can more effectively confine the movement direction of the ions released by the thermal runaway suppression component 10. The material of the etching direction confinement layer 36 can be selected from passive metals, glass, or polymers that do not react with the molten composite salt layer 15.

[0078] Please see Figure 13 In this embodiment, the open side surface of the first collector layer 26 is provided with several grooves 38 with open top surfaces, and the thermal runaway suppression component 10 of the present invention is disposed within the grooves 38. This allows the sidewalls of the grooves 38 to restrict the etching direction of the thermal runaway suppression component 10 and reduces the thickness of the first collector layer 26 that needs to be etched through. Alternatively, as... Figure 14 As shown, several bumps 39 are formed on the open side surface of the first collector layer 26. The material of these bumps can be selected from passive metals, glass, or polymers. Several grooves 38 are formed on the surface of the first collector layer 26 exposed outside the bumps 39 to accommodate the thermal runaway suppression component 10. Alternatively, several etch-aid cutting lines 41 that do not penetrate the first collector layer 26 are formed on the open side surface of the first collector layer 26 to facilitate etching, such as... Figure 15 As shown.

[0079] In addition, in the above-mentioned embodiments using etching, when the substrate in the thermal runaway suppression component is directly the current collector layer of a lithium battery, in order to make the contact between the composite salt layer and the current collector layer more complete, nano-sized ceramic powder can be added to the composite salt. It is passive to the composite salt layer, so that when the composite salt melts, the weight and surface tension of the nano-sized ceramic powder will increase the filling ability.

[0080] In summary, this invention provides a lithium battery thermal runaway suppression component and its application. The component uses the temperature state of the lithium battery as its activation mechanism. After activation, it reacts with the components of the lithium battery's electrochemical reaction system to form a positive passivation layer on the surface of the active material powder at the positive terminal and a negative passivation layer at the negative terminal. Furthermore, after melting, the thermal runaway suppression component etches the aluminum current collector layer, causing a discharge effect and reducing the state of charge (SOC). It can also contaminate the interfaces of the ion conduction pathways in the electrochemical reaction system, such as the interfaces between solid electrolytes or between the solid electrolyte and the active material, increasing the difficulty of ion conduction and charge transfer. Moreover, the thermal runaway suppression component also induces polymerization and carbonization reactions in the liquid / gel / gel electrolytes, causing structural damage to the polymer electrolyte and terminating or reducing its ion conduction capacity. When the lithium battery temperature reaches the default temperature, the thermal runaway suppression component can effectively and rapidly terminate or reduce the electrochemical reaction by simultaneously implementing the above-mentioned operating mechanisms, effectively stopping the thermal runaway of the lithium battery and improving its safety.

[0081] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of the invention. Therefore, all equivalent changes or modifications made to the features and spirit described in the claims of the present invention should be included within the scope of protection of the present invention.

Claims

1. A lithium battery thermal runaway suppression component, which is applied to a lithium battery capable of charging and discharging, the lithium battery thermal runaway suppression component includes a composite salt layer, which is formed by the co-melting of at least two or more inorganic single salts, the melting temperature of the composite salt layer is 90-150°C, and at least one of the inorganic single salts is an alkali metal cation or an amphoteric element cation.

2. The lithium battery thermal runaway suppression component according to claim 1, wherein the inorganic single salt is selected from LiNO3, AlCl3, NaCl, KCl, LiCl, AlBr2, Ca(NO3)2, NaNO3, KNO3, ZnCl4, FeCl3 or FeBr3.

3. The lithium battery thermal runaway suppression component according to claim 1 further comprises at least one organic salt selected from tetrabutylammonium chloride, (1-butyl-3-methylimidazolium chloride), (1-ethyl-3-methylimidazolium chloride), tetrabutylammonium bromide, tetraheptylammonium bromide, or hexadecyltributylphosphine bromide.

4. The lithium battery thermal runaway suppression component according to claim 1 further comprises a substrate for supporting the composite salt layer, wherein the material of the substrate is selected from a passive material that does not react with the composite salt layer in the molten state.

5. The lithium battery thermal runaway suppression component according to claim 4, wherein the substrate has pores.

6. The lithium battery thermal runaway suppression component according to claim 5, wherein the substrate is formed by stacking metal oxide particles or by weaving glass fibers.

7. The lithium battery thermal runaway suppression component according to claim 1, wherein the surface of the composite salt layer has a protective layer, the material of which is selected from thermoplastic polymers, thermosetting polymers or liquid metals.

8. The lithium battery thermal runaway suppression component according to claim 1, wherein the composite salt layer contains nano-scale ceramic powder, which is passive to the composite salt layer.

9. A lithium battery having a thermal runaway suppression component, comprising: One encapsulated component; An electrochemical reaction system, housed within an encapsulation assembly; and A lithium battery thermal runaway suppression component is disposed outside or inside a packaged component. The lithium battery thermal runaway suppression component includes a composite salt layer, which is formed by the co-melting of at least two kinds of inorganic single salts. The melting temperature of the composite salt layer is 90-150℃. At least one of the inorganic single salts is an alkali metal cation or an amphoteric element cation.

10. The lithium battery with thermal runaway suppression component according to claim 9, wherein the inorganic single salt is selected from LiNO3, AlCl3, NaCl, KCl, LiCl, AlBr2, Ca(NO3)2, NaNO3, KNO3, ZnCl4, FeCl3 or FeBr3.

11. The lithium battery with thermal runaway suppression component according to claim 9, wherein the composite salt layer further comprises at least one organic salt selected from tetrabutylammonium chloride, (1-butyl-3-methylimidazolium chloride), (1-ethyl-3-methylimidazolium chloride), tetrabutylammonium bromide, tetraheptylammonium bromide or hexadecyltributylphosphine bromide.

12. The lithium battery with a thermal runaway suppression component according to claim 9, wherein the lithium battery thermal runaway suppression component further comprises a substrate for supporting the composite salt layer, the material of the substrate being selected from a passive material that does not react with the composite salt layer in the molten state.

13. The lithium battery with thermal runaway suppression components according to claim 12, wherein the substrate has pores.

14. The lithium battery with thermal runaway suppression components according to claim 13, wherein the substrate is formed by stacking metal oxide particles or by weaving glass fibers.

15. The lithium battery with a thermal runaway suppression component according to claim 9, wherein when the lithium battery thermal runaway suppression component is disposed outside the encapsulation component, the encapsulation component has a plurality of through holes, one end of which is connected to the lithium battery thermal runaway suppression component and the other end of which is connected to the electrochemical reaction system.

16. The lithium battery with a thermal runaway suppression component according to claim 15, wherein the encapsulation component comprises: First collector layer; A second collector layer is provided, which is corresponding to the first collector layer; A plastic frame, with the first collector layer glued to one end and the second collector layer glued to the other end.

17. The lithium battery with a thermal runaway suppression component according to claim 16, wherein the lithium battery thermal runaway suppression component is disposed on the outer surface of the first current collector layer, and the first current collector layer is made of aluminum.

18. The lithium battery with thermal runaway suppression component according to claim 16, wherein the electrochemical reaction system comprises a positive electrode active material; a negative electrode active material; and an isolation layer sandwiched between the positive electrode active material and the negative electrode active material, wherein the positive electrode active material is in direct contact with the first current collector layer, and the negative electrode active material is in direct contact with the second current collector layer.

19. The lithium battery with thermal runaway suppression components according to claim 16, wherein the through-hole is located in the first current collector layer and / or the second current collector layer.

20. The lithium battery with thermal runaway suppression components according to claim 19, further comprising a removable gate layer covering the through hole.

21. The lithium battery with thermal runaway suppression component according to claim 20, wherein the gate layer is made of silicone polymer.

22. The lithium battery with thermal runaway suppression component according to claim 20, wherein the open side of the first current collector layer and / or the second current collector layer has a plurality of grooves with corresponding through holes, and the gate layer is disposed in the groove.

23. The lithium battery with thermal runaway suppression components according to claim 9, wherein the surface of the composite salt layer is covered with a protective layer, the material of which may be selected from thermoplastic polymers, thermosetting polymers or liquid metals.

24. The lithium battery with a thermal runaway suppression component according to claim 9, wherein the sidewall of the thermal runaway suppression component is provided with a directional confinement layer to restrict the direction of flow when the composite salt layer melts, and the material of the directional confinement layer is selected from a passive material that does not react with the molten composite salt layer.

25. The lithium battery with thermal runaway suppression components according to claim 9, wherein the salt used in the electrolyte of the electrochemical reaction system has O=S=O bonds.

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