Sulfide solid-state battery module and electric equipment

Abstract

The invention relates to the field of batteries, in particular to a sulfide solid-state battery module and electric equipment. The sulfide solid-state battery module comprises a shell and a plurality of battery monomers arranged in the shell, and ionic liquid is arranged among the battery monomers. According to the sulfide solid-state battery module, the ionic liquid is introduced into the battery module hierarchically, so that a secondary safety defense line integrating hydrogen sulfide gas absorption, efficient heat conduction and buffer protection is innovatively constructed, and the safety strategy conversion from passive suppression to active management is realized; according to the scheme, the problems of H2S poison and corrosion can be solved from the source level and the process level through hydrophobicity and absorptivity of the ionic liquid, the thermal management performance of the module is remarkably optimized through thermal conductivity of the ionic liquid, and meanwhile the structure is simplified through the highly-integrated design; and finally, the safety, the reliability and the comprehensive performance of the sulfide solid-state battery module are fundamentally improved, and key obstacles are removed for commercial application of the sulfide solid-state battery module.

Description

Technical Field

[0001] This invention relates to the field of batteries, and more specifically, to a sulfide solid-state battery module and an electrical device. Background Technology

[0002] Sulfide solid-state batteries are considered strong candidates for next-generation high-energy-density energy storage systems due to their high ionic conductivity and good interfacial contact performance. However, the generation of hydrogen sulfide (H2S) gas in sulfide battery systems has become a prominent safety and environmental issue.

[0003] The generation of hydrogen sulfide gas mainly originates from side reactions between sulfide electrolytes and moisture or electrode materials. Typical sulfide electrolytes, such as Li₂S and Na₂S, are extremely sensitive to moisture. Even trace amounts of moisture entering the battery can trigger the following chemical reactions: Li₂S + 2H₂O → 2LiOH + H₂S↑; This reaction not only damages the electrolyte structure but also releases hydrogen sulfide gas, which is highly corrosive and toxic. Furthermore, during battery charging and discharging, increased temperature further accelerates side reactions and exacerbates H2S formation.

[0004] Hydrogen sulfide gas poses multiple hazards to battery systems: 1. Corrosiveness: H2S can react with metal components such as copper and iron inside the battery to form metal sulfides, which reduce conductivity, increase internal resistance, and affect battery life and performance. 2. Toxicity: H2S is a highly toxic gas. Low concentrations can cause headaches and nausea in humans, while high concentrations can lead to respiratory paralysis, coma, or even death, posing a serious health threat to operators in the production, use, and recycling processes.

[0005] Currently, the main technical means to suppress hydrogen sulfide gas generation are focused on the battery cell level, such as doping or coating the electrolyte material, optimizing the sealing structure to prevent moisture intrusion, or adding H2S absorbents inside the battery cell. However, these methods still have limitations in practical applications, especially after the batteries are assembled into modules. If a gas absorption mechanism is not set up at the module level, the overflowing H2S gas will still pose a serious threat to the safety of personnel and equipment.

[0006] Therefore, there is an urgent need for a technical solution that can effectively absorb hydrogen sulfide gas and improve system safety performance from the battery module system level.

[0007] In view of this, the present invention is hereby proposed. Summary of the Invention

[0008] In existing technologies, methods for suppressing hydrogen sulfide gas focus on the interior of sulfide battery cells. However, these methods cannot completely prevent the gas from escaping into the module environment throughout the battery's lifespan. Therefore, the technical problem this invention aims to solve is: how to prevent hydrogen sulfide gas escaping from individual cells from accumulating in the internal space of the module during battery module assembly, use, and maintenance, thereby ensuring the personal safety of operators and maintenance personnel.

[0009] In order to achieve the above-mentioned objectives of the present invention, the following technical solution is adopted: One aspect of the present invention relates to a sulfide solid-state battery module, comprising a housing and a plurality of battery cells disposed within the housing; an ionic liquid is disposed between the battery cells.

[0010] This sulfide solid-state battery module innovatively constructs a secondary safety defense line that integrates hydrogen sulfide gas absorption, efficient thermal conductivity, and buffer protection by introducing ionic liquids at the battery module level, realizing a shift in safety strategy from "passive suppression" to "active management." This solution not only addresses H2S toxicity and corrosion issues at both the source and process levels through the hydrophobicity and absorption properties of ionic liquids, but also significantly optimizes the module's thermal management performance through its thermal conductivity. Furthermore, the highly integrated design simplifies the structure, ultimately fundamentally improving the safety, reliability, and overall performance of the sulfide solid-state battery module, removing key obstacles to its commercial application.

[0011] Preferably, the ionic liquid comprises: 1-butyl-3-methylimidazolium hexafluorophosphate and / or 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide.

[0012] Preferably, an insulating and thermally conductive porous buffer layer is provided between the battery cells, and the ionic liquid is filled in the insulating and thermally conductive porous buffer layer.

[0013] Preferably, the insulating and thermally conductive porous buffer layer is made of porous polymer materials and / or graphene.

[0014] Preferably, the porous polymer material includes: ceramic foam and / or porous polytetrafluoroethylene.

[0015] Preferably, the porosity of the insulating and thermally conductive porous buffer layer is 80%~90%.

[0016] Preferably, the volume of the ionic liquid is 80% to 90% of the pore volume inside the insulating and thermally conductive porous buffer layer.

[0017] Another aspect of the present invention relates to an electrical device comprising the aforementioned sulfide solid-state battery module.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. Fundamental Enhancement of Security: Building a Secondary Security Defense Line This invention solves the H2S gas hazard problem at the system level of the battery module for the first time. By placing an ionic liquid in the space between battery cells, an independent "secondary safety defense line" is constructed, which can actively absorb H2S gas escaping from any battery cell, realizing in-situ treatment of leaked gas and fundamentally preventing the accumulation of toxic gases within the module and endangering personnel safety.

[0019] Existing technologies focus only on "suppressing" H2S generation within individual battery cells, while this invention provides an effective means of "managing" and "eliminating" the gas after it is generated, resulting in a more comprehensive and reliable safety strategy.

[0020] 2. Highly integrated functions, achieving synergistic efficiency. Ionic liquids simultaneously perform three major functions: thermal conduction, gas absorption, and buffering (when combined with porous materials), replacing the separate thermal pads, gas filters, and cushioning foams in traditional designs. This highly integrated design significantly simplifies the module structure, reduces the number of parts and assembly complexity, and provides room to increase the energy density of the battery pack.

[0021] 3. Optimized thermal management performance Compared to air, ionic liquids have a higher thermal conductivity. When they fill the gaps between battery cells or are incorporated into porous materials, they can effectively reduce the contact thermal resistance between batteries, establish efficient heat conduction paths, significantly improve the heat dissipation uniformity of the module, avoid local overheating, thereby extending battery life and improving fast charging performance.

[0022] 4. Enhanced system reliability and lifespan The selected ionic liquids (such as [BMIM][PF6], [EMIM][Tf2N]) have extremely strong hydrophobicity, which can effectively isolate the contact between environmental moisture and sulfide electrolytes, reducing the generation of H2S gas at the source, and achieving a combination of "prevention" and "treatment".

[0023] When ionic liquids are combined with elastic porous buffer layers, the composite material can not only absorb gases and conduct heat, but also effectively buffer the volume expansion and contraction of the battery during cycling, reduce mechanical stress, and improve the structural stability and cycle life of the entire module. Detailed Implementation

[0024] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. However, those skilled in the art will understand that the embodiments described below are some embodiments of the present invention, but not all embodiments, and are only used to illustrate the present invention, and should not be regarded as limiting the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall be followed. Where the manufacturers of reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0025] One aspect of the present invention relates to a sulfide solid-state battery module, comprising a housing and a plurality of battery cells disposed within the housing; an ionic liquid is disposed between the battery cells.

[0026] The aforementioned sulfide solid-state battery module innovatively constructs a secondary safety defense line that integrates hydrogen sulfide gas absorption, efficient thermal conductivity, and buffer protection by introducing ionic liquids at the battery module level. This achieves a shift in safety strategy from "passive suppression" to "active management." This solution not only addresses H2S toxicity and corrosion issues at both the source and process levels through the hydrophobicity and absorption properties of ionic liquids, but also significantly optimizes the module's thermal management performance through its thermal conductivity. Furthermore, the highly integrated design simplifies the structure, ultimately fundamentally improving the safety, reliability, and overall performance of the sulfide solid-state battery module, removing key obstacles to its commercial application.

[0027] Furthermore, the ionic liquid comprises: 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]) and / or 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([EMIM][Tf2N]). The ionic liquid can conduct heat generated by the battery module, and simultaneously, it possesses hydrogen sulfide gas absorption properties, absorbing hydrogen sulfide gas generated by the battery cells.

[0028] Furthermore, an insulating and thermally conductive porous buffer layer is provided between the individual battery cells, and the ionic liquid is filled in the insulating and thermally conductive porous buffer layer.

[0029] Filling the porous buffer layer with ionic liquid can relieve the pressure between battery cells, and the addition of ionic liquid can simultaneously serve the functions of heat conduction and hydrogen sulfide gas absorption.

[0030] Furthermore, the material of the insulating and thermally conductive porous buffer layer includes: porous polymer materials and / or graphene.

[0031] Furthermore, the porous polymer material includes: ceramic foam and / or porous polytetrafluoroethylene.

[0032] High-porosity insulating porous materials (such as ceramic foam or porous polytetrafluoroethylene with a porosity of 80%-90%) are selected as carriers. Ionic liquids are vacuum impregnated into the pores to form a composite heat dissipation layer of "porous matrix + ionic liquid," which is then placed between the battery cells. The porous material's framework provides insulation support, while the ionic liquid fills the pores to form thermally conductive pathways. Furthermore, the ionic liquid can adsorb hydrogen sulfide gas within the pores.

[0033] Furthermore, an insulating, thermally conductive, porous buffer layer filled with ionic liquid is disposed near the electrode.

[0034] Furthermore, the porosity of the insulating and thermally conductive porous buffer layer is 80% to 90%, including but not limited to point values ​​of any one of 70%, 75%, 80%, 85%, 90%, 95% or 100%, or a range between any two.

[0035] Furthermore, the volume of the ionic liquid is 70% to 100% of the pore volume inside the insulating and thermally conductive porous buffer layer, including but not limited to any one of 70%, 75%, 80%, 85%, 90%, 95%, or 100%, or a range between any two. If the filling is insufficient, a large amount of air will remain in the pores. Air is a poor conductor of heat, which will severely degrade the overall thermal conductivity, and the gas absorption capacity will also be greatly reduced. If the filling is excessive, the ionic liquid is prone to overflow, causing safety issues.

[0036] Another aspect of the present invention relates to an electrical device comprising the aforementioned sulfide solid-state battery module.

[0037] The embodiments of the present invention will be described in detail below with reference to examples. However, those skilled in the art will understand that the following examples are for illustrative purposes only and should not be considered as limiting the scope of the invention. Unless otherwise specified in the examples, conventional conditions or conditions recommended by the manufacturer are followed. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0038] Example 1 The sulfide solid-state battery module provided in this embodiment includes a housing and a plurality of battery cells disposed within the housing; an ionic liquid is disposed between the battery cells; an insulating and thermally conductive porous buffer layer is disposed between the battery cells, and the ionic liquid is filled in the insulating and thermally conductive porous buffer layer. The ionic liquid is: 1-butyl-3-methylimidazolium hexafluorophosphate; The insulating and thermally conductive porous buffer layer is made of porous polytetrafluoroethylene. The porosity of the insulating and thermally conductive porous buffer layer is 85%. The volume of the ionic liquid is 85% of the pore volume inside the insulating and thermally conductive porous buffer layer.

[0039] Example 2 The sulfide solid-state battery module provided in this embodiment includes a housing and a plurality of battery cells disposed within the housing; an ionic liquid is disposed between the battery cells; an insulating and thermally conductive porous buffer layer is disposed between the battery cells, and the ionic liquid is filled in the insulating and thermally conductive porous buffer layer. The ionic liquid is 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt; The insulating and thermally conductive porous buffer layer is made of graphene. The porosity of the insulating and thermally conductive porous buffer layer is 90%. The volume of the ionic liquid is 80% of the pore volume inside the insulating and thermally conductive porous buffer layer.

[0040] Example 3 The sulfide solid-state battery module provided in this embodiment includes a housing and a plurality of battery cells disposed within the housing; an ionic liquid is disposed between the battery cells; an insulating and thermally conductive porous buffer layer is disposed between the battery cells, and the ionic liquid is filled in the insulating and thermally conductive porous buffer layer. The ionic liquids are: 1-butyl-3-methylimidazolium hexafluorophosphate and 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide. The insulating and thermally conductive porous buffer layer is made of ceramic foam; The porosity of the insulating and thermally conductive porous buffer layer is 80%. The volume of the ionic liquid is 90% of the pore volume inside the insulating and thermally conductive porous buffer layer.

[0041] Comparative Example 1 The only difference between this comparative example and Example 1 is that the porous buffer layer is not filled with ionic liquid.

[0042] Experimental Example The hydrogen sulfide production of the battery modules provided in each embodiment and comparative example was tested. The test results are shown in Table 1. Sensors were placed in the exhaust channel, near the pressure relief valve, or in the gaps inside the pack of the battery module for real-time and continuous monitoring.

[0043] Table 1

[0044] As shown in Table 1, the sulfide solid-state battery module provided by this invention, which incorporates ionic liquid between battery cells, is a necessary and efficient technical means to solve the critical problem of H2S gas accumulation inside the module. This solution successfully constructs an independent secondary safety defense line, realizing a paradigm shift in safety strategies and fundamentally improving the system safety of the battery module, thus removing a major obstacle to its commercial application.

[0045] Although the present invention has been illustrated and described with specific embodiments, it should be understood that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; those skilled in the art should understand that modifications can be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein, without departing from the spirit and scope of the present invention; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A sulfide solid-state battery module, characterized in that, It includes a housing and a plurality of battery cells disposed within the housing; an ionic liquid is disposed between the battery cells.

2. The sulfide solid-state battery module according to claim 1, characterized in that, The ionic liquid comprises: 1-butyl-3-methylimidazolium hexafluorophosphate and / or 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide.

3. The sulfide solid-state battery module according to claim 1 or 2, characterized in that, An insulating and thermally conductive porous buffer layer is disposed between the individual battery cells, and the ionic liquid is filled in the insulating and thermally conductive porous buffer layer.

4. The sulfide solid-state battery module according to claim 3, characterized in that, The insulating and thermally conductive porous buffer layer is made of porous polymer materials and / or graphene.

5. The sulfide solid-state battery module according to claim 4, characterized in that, The porous polymer material includes: ceramic foam and / or porous polytetrafluoroethylene.

6. The sulfide solid-state battery module according to claim 3, characterized in that, The porosity of the insulating and thermally conductive porous buffer layer is 80%~90%.

7. The sulfide solid-state battery module according to claim 3, characterized in that, The volume of the ionic liquid is 80% to 90% of the pore volume inside the insulating and thermally conductive porous buffer layer.

8. An electrical appliance, characterized in that, Includes the sulfide solid-state battery module according to any one of claims 1 to 7.

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