Electrode for lithium sulfur battery and lithium sulfur battery including the same

Description

1 / 38 “ELECTRODE FOR LITHIUM-SULFUR BATTERY AND LITHIUM-SULFUR BATTERY INCLUDING THE SAME” TECHNICAL FIELD

[001] The present disclosure relates to an electrode for a lithium-sulfur battery and to a lithium-sulfur battery including the same.

[002] This application is based on and claims priority to Korean Patent Application No. 10-2023-0167317, filed on November 27, 2023 with the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference. FUNDAMENTALS

[003] As the application range of secondary lithium batteries expands not only to portable electronic devices but also to electric vehicles (EVs) and energy storage systems (ESSs), the demand for high-capacity, high-energy-density, and long-life secondary lithium batteries is increasing.

[004] Among various secondary lithium batteries, a lithium-sulfur battery is a battery system in which a sulfur-based material containing sulfur-sulfur bonds is used as a positive electrode active material, and a lithium metal, a carbon-based material through which lithium ions are intercalated / deintercalated, or silicon or tin that forms an alloy with lithium, is used as a negative electrode active material.

[005] Sulfur is the main active material of the positive electrode in lithium-sulfur batteries and is advantageous because it has low weight per atom, is easy to supply and inexpensive due to its abundant resources, is non-toxic and is an environmentally friendly material. SUMMARY TECHNICAL PROBLEM Petition 870250085671, dated 09 / 22 / 2025, page 53 / 94 2 / 38

[006] The present disclosure provides an electrode for implementing a high energy density lithium-sulfur battery and a lithium-sulfur battery including the same.

[007] In one aspect, the present disclosure provides an electrode in which the weight of the electrode is reduced so that the proportion of the active material relative to the total weight of the electrode can be increased, and the weight ratio of the current collector can be reduced.

[008] In one aspect, the present disclosure provides an electrode in which the proportion of the active material can be increased relative to the total weight of the electrode, even when the amount of electrode charge is relatively low.

[009] In one aspect, the present disclosure provides a lithium-sulfur battery in which the proportion of the active material relative to the total weight of the electrode is relatively high and, therefore, a relatively high energy density is implemented. TECHNICAL SOLUTION

[010] According to one aspect of the present disclosure, an electrode of the following embodiments is provided.

[011] An electrode according to a first embodiment includes: a current collector; and an electrode active material layer located on at least one side of the current collector. The electrode active material layer includes a sulfur-carbon composite and a binder. The sulfur-carbon composite includes a porous carbon material and a sulfur-based material. The current collector includes aluminum (Al) and has a thickness of about 9 μm or less.

[012] According to a second embodiment, the electrode of the first embodiment satisfies a value based on the following equation 1 of 90 cm2 / mAh or more. [Equation 1] (weight of the electrode — weight of the current collector) 1 weight of the current collector amount of charge on the electrode Petition 870250085671, dated 09 / 22 / 2025, page 54 / 94 3 / 38

[013] In equation 1 above, the electrode weight unit and the current collector weight unit are grams (g), and the electrode charge quantity is a quantity of sulfur charge on the electrode, and its unit is mAh / cm2.

[014] According to a third modality, in the first modality or in the second modality, the value based on equation 1 above can satisfy 100 cm2 / mAh up to 150 cm2 / mAh.

[015] According to a fourth embodiment, in any of the first to third embodiments, the thickness of the current collector can be from about 5 μm to 9 μm.

[016] According to a fifth embodiment, in any of the first to fourth embodiments, the content of the sulfur-based material in the electrode active material layer may be about 65% by weight or more.

[017] According to a sixth mode, in any of the first to fifth modes, the amount of sulfur charge can be about 5 mAh / cm2 or less.

[018] According to a seventh mode, in any of the first to sixth modes, the amount of sulfur charge can be about 3.5 mAh / cm2 or less.

[019] According to another aspect of the present disclosure, a lithium-sulfur battery of the following embodiments is provided.

[020] A lithium-sulfur battery, according to an eighth embodiment, includes a positive electrode, a negative electrode, a separator interposed between the positive and negative electrodes, and an electrolyte. At least one of the positive and negative electrodes may be an electrode according to any of the first to seventh embodiments.

[021] According to a ninth embodiment, the weight ratio (El / S) of the electrolyte to sulfur in the eighth embodiment may be about 3.5 g / g or less. Petition 870250085671, dated 09 / 22 / 2025, p. 55 / 94 4 / 38

[022] According to a tenth embodiment, the energy density of the lithium-sulfur battery in the eighth embodiment or in the ninth embodiment may be around 350 Wh / kg or more. ADVANTAGEOUS EFFECTS

[023] According to one aspect of the present disclosure, there is an advantage in that the weight ratio of the active material is increased relative to the total weight of the electrode.

[024] Furthermore, even in an electrode with a relatively low amount of active material charge, the weight ratio of the active material to the total weight of the electrode can be increased, thus exhibiting an advantage as the energy density of a battery using the electrode is increased.

[025] Furthermore, according to one aspect of the present disclosure, the weight ratio of the current collector to the total weight of the electrode is relatively low, thus exhibiting an advantage in the implementation of the high energy density lithium-sulfur battery. BRIEF DESCRIPTION OF THE DRAWINGS

[026] Figure 1 is a graph that illustrates the weight ratio of a current collector in a bag-type battery according to the thickness of the current collector (Al foil) in relation to Comparative Examples 1 to 6 and Examples 1 to 4.

[027] Figure 2 is a graph that illustrates the relative energy density value of a battery according to the thickness of the current collector (Al foil) in relation to Comparative Examples 1 to 6 and Examples 1 to 4. DETAILED DESCRIPTION

[028] The present revelation will be described in detail below.

[029] Terms or words used in this descriptive report and claims should not be interpreted as limited to ordinary meanings, Petition 870250085671, dated 09 / 22 / 2025, page 56 / 94 5 / 38 usual or dictionary definitions, and should be interpreted as meanings and concepts consistent with the technical idea of ​​the present disclosure based on the principle that the inventor can appropriately define the concept of the terms to best explain his own invention.

[030] Throughout this descriptive report, when a particular part is said to “include” or “have” a particular component, this means that the particular part may include other components rather than excluding other components, unless specifically stated otherwise.

[031] Furthermore, the terms “about”, “substantially”, etc., used throughout this descriptive report, are used to mean the corresponding numerical values ​​or approximations of numerical values ​​when inherent manufacturing and material tolerances are presented in the aforementioned meaning, and are used to prevent infringers from misusing the disclosed content in which precise or absolute numbers are mentioned to aid understanding of this application.

[032] Throughout this descriptive report, the description of “A and / or B” means “A or B or both”.

[033] In this descriptive report, the “specific surface area” is measured by a Brunauer-Emmett-Teller (BET) measurement method and can be calculated from a nitrogen gas absorption quantity using, for example, BELSORP-mini II from BEL Japan under a liquid nitrogen temperature (77 K).

[034] The term “(poly)sulfide” used in this descriptive report is a concept that includes both the “(poly)sulfide ion (Sx2-, 1 < x < 8)” and “(poly)sulfide lithium (Li2Sx or LiSx-, 1 < x < 8)”.

[035] The term “polysulfide” used in this descriptive report is a concept that includes both the “polysulfide ion (Sx2-, 1 < x < 8)” and “lithium polysulfide”. Petition 870250085671, dated 09 / 22 / 2025, page 57 / 94 6 / 38 (Li2SxOr LiSx-, 1 < x < 8)”.

[036] The term “composite” used in this descriptive report refers to a substance in which two or more materials are combined to form physically and chemically distinct phases and exhibit more effective functions.

[037] The term “porosity” used in this descriptive report refers to the ratio of the volume occupied by pores to the total volume of a given structure, uses % by volume as its unit and can be used interchangeably with terms such as pore ratio and void ratio.

[038] Unless otherwise specified in this descriptive report, porosity may have a value obtained by means of the following relational expression using the apparent density measured for the target material and the actual density. The actual density is calculated based on the actual density and the component composition that constitutes the target material. Porosity (% by volume) = {1 - (apparent density / real density)} x 100

[039] In this descriptive report, “particle diameter D10” means a particle size based on 10% of the cumulative particle size distribution in the volume of target particles being measured, “particle diameter D50” means a particle size based on 50% of the cumulative particle size distribution in the volume of target particles being measured, and “particle diameter D90” means a particle size based on 90% of the cumulative particle size distribution in the volume of target particles being measured.

[040] Each of the particle diameters D10, D50 and D90 can be measured using a laser diffraction method. For example, for the measurement, target particle powder is dispersed in a dispersion medium and then introduced into a commercially available laser diffraction particle size measuring device (e.g., Microtrac MT 3000) and irradiated with ultrasonic waves of about 28 kHz with an output of 60 W. Then, after a graph of Petition 870250085671, dated 09 / 22 / 2025, page 58 / 94 7 / 38 cumulative volume particle size distribution to be obtained, the respective particle sizes corresponding to 10%, 50% and 90% in the cumulative volume distribution are obtained.

[041] The present disclosure relates to an electrode for an electrochemical device and an electrochemical device including the electrode, for example, a secondary battery. The secondary battery may be a lithium secondary battery. The electrode according to the present disclosure may be at least one of a positive electrode and a negative electrode, and may be a positive electrode including, for example, sulfur as an active material. Furthermore, the electrode includes a sulfur-based material as an active material, and the lithium secondary battery that includes such an electrode may be a lithium-sulfur secondary battery (or a lithium-sulfur battery).

[042] The lithium-sulfur battery has a theoretical energy density of 2,600 Wh / kg when a theoretical specific capacity resulting from the conversion reaction (S8 + 16Li++ 16e--> 8Li2S) of lithium and sulfur ions in the positive electrode is 1,675 mAh / g, and lithium metal is used as the negative electrode. This has a very high value in theoretical energy density compared to other battery systems currently under study (Ni-MH battery: 450 Wh / kg, Li-FeS battery: 480 Wh / kg, Li-MnO2 battery: 1,000 Wh / kg, Na-S battery: 800 Wh / kg) and lithium-ion batteries (250 Wh / kg) and is therefore attracting attention as a high-capacity, environmentally friendly and inexpensive secondary lithium battery among secondary batteries currently under development.

[043]

[0001] However, there is a problem: the theoretical capacity may not be fully implemented due to the large amount of electrolyte, the decrease in the efficiency of the positive electrode, and the deterioration of the negative electrode. Therefore, the energy density has not yet been sufficiently increased. Consequently, research continues to implement a lithium-sulfur battery with Petition 870250085671, dated 09 / 22 / 2025, page 59 / 94 8 / 38 high energy density.

[044] In lithium-sulfur batteries, since the density of the sulfur-carbon composite used for the positive electrode is low, when a current collector is coated with the sulfur-carbon composite, the density of the current collector becomes relatively high. Thus, the weight ratio of the current collector to the total weight of the electrode increases. Therefore, in reality, the weight ratio of the current collector to the electrode is relatively high, making it difficult to implement a high-energy-density battery (e.g., a bag-type battery). Furthermore, the ratio of active material in the electrode decreases when a low-charge electrode is implemented, decreasing the amount of charge for various purposes, such as increasing the utilization rate of carbon surface in the positive electrode and thus increasing the electrochemical reaction rate. Similarly, it has been difficult to implement a battery with high energy density.

[045] According to one embodiment of the present disclosure, an electrode is provided in which the weight of the electrode is reduced so that the portion of the active material relative to the total weight of the electrode can be increased, and the weight ratio of the current collector can be reduced. Electrode

[046] The electrode according to one aspect of the present disclosure is an electrode comprising a current collector and an electrode active material layer located on at least one side of the current collector. The electrode active material layer comprises a sulfur-carbon composite and a binder.

[047] According to one aspect of the present disclosure, the sulfur and carbon composite includes a porous carbon material and a sulfur-based material.

[048] According to one aspect of the present disclosure, the thickness of the current collector is about 9 μm or less. Petition 870250085671, dated 09 / 22 / 2025, pp. 60 / 94 9 / 38 Sulfur and Carbon Composite

[049] According to one embodiment of the present disclosure, an electrode that can be used for a high energy density electrochemical device is implemented in which the thickness of the current collector is relatively thin compared with a conventional electrode that uses, as an active material, a sulfur and carbon composite in which a sulfur-based material (as an active material) is supported on a porous carbon material and is complexed.

[050] For example, in one embodiment of the present disclosure, the sulfur and carbon composite may include an active material for the positive electrode and may be bonded to the binder to form an electrode active material layer. The sulfur and carbon composite includes a porous carbon material and a sulfur-based material.

[051] In one embodiment of the present disclosure, the sulfur-based material is included as an active material in an electrochemical device, such as, for example, a secondary battery, a lithium secondary battery, a lithium-sulfur battery, etc., and any material may be used as the sulfur-based material, without limitation, provided that it is used as an active material in a lithium-sulfur battery. For example, the sulfur-based material may be inorganic sulfur (S8), lithium (poly)sulfide (Li2Sx or LiSx-, 1 < x < 8), an organic sulfur compound, a carbon-sulfur polymer, or a mixture of two or more types thereof. In one embodiment of the present disclosure, the organic sulfur compound may be, for example, 2,5-dimercapto-1,3,4-thiadiazole, 1,3,5-trithiocyanic acid, or a mixture thereof, but without limitation.In one embodiment of the present disclosure, the carbon-sulfur polymer may be an example of one having the chemical formula (C2Sx)n (x=2.5 to 50, n>2), but the present disclosure is not limited to this.

[052] In one embodiment of the present disclosure, the carbon material Petition 870250085671, dated 09 / 22 / 2025, pp. 61 / 94 10 / 38 porous material can be any carbon material, without limitation, provided it has a porous structure to support the sulfur-based material and has electrical conductivity so as to improve the electrical conductivity of the electrode active material layer when the sulfur-based material, having little or no electrical conductivity, is used for the electrode active material layer. For example, the porous carbon material can be carbon nanotubes, carbon black, graphite, activated carbon, graphene, or a mixture of two or more types thereof, but the present disclosure is not limited to this.

[053] For example, the sulfur-carbon composite may have a structure in which the sulfur-based material is supported on the outer surface of the porous carbon material and / or on the inner surface of the pores, but without limitation.

[054] In one embodiment of the present disclosure, in the sulfur-carbon composite, the sulfur-based material can be included by physical adsorption with the porous carbon material, or by chemical bonding, such as covalent bonding or van der Waals forces between a sulfur (S) element and carbon in the porous carbon material. In particular, the sulfur-based material can be chemically bonded to the surface of the porous carbon material to form the composite.

[055] In one embodiment of the present disclosure, the sulfur-carbon composite can be complexed by simply mixing the sulfur-based material and the carbon material, or it can have a coating form or a core-shell support form. In the coating form of the core-shell structure, the sulfur-based material or the carbon material is coated onto another material. For example, the surface of the carbon material can be surrounded with sulfur, or vice versa. Furthermore, in the support form, the sulfur-based material can be filled into the interior of the carbon material, particularly in the internal pores. As for the form of the sulfur-carbon composite, any form can be used, provided it satisfies the suggested content ratio. Petition 870250085671, dated 09 / 22 / 2025, pp. 62 / 94 11 / 38 above sulfur and carbon materials, and is not limited in the present disclosure.

[056] In one embodiment of the present disclosure, in the sulfur and carbon composite, the content of the element sulfur (S) may be about 60% by weight or more, 70% by weight or more, or 75% by weight or more, and 99% by weight or less relative to 100% by weight of the sulfur and carbon composite. For example, in the sulfur and carbon composite, the content of the element sulfur (S) may be about 60% by weight to 99% by weight, 70% by weight to 99% by weight, 60% by weight to 90% by weight, 75% by weight to 90% by weight, 70% by weight to 85% by weight, 70% by weight to 80% by weight, 75% by weight to 80% by weight, or 70% by weight to 75% by weight relative to 100% by weight of the sulfur and carbon composite.

[057] In the sulfur-carbon composite according to the present disclosure, the sulfur-based material is located on at least one of the outer surface of the porous carbon material and the inner surface of the pores. Herein, the sulfur-based material may be present in an area less than 100% of the entire inner and outer surface of the porous carbon material, for example, in an area of ​​about 1% to 95%, or about 60% to 90%. When sulfur is present on the surface of the porous carbon material within the above range, the maximum effect can be exhibited in terms of electron transfer area and electrolyte wettability. For example, the surface of the porous carbon material is thinly and uniformly impregnated with sulfur in the area of ​​the above range and therefore the electron transfer contact area can be increased during charge / discharge processes.When sulfur covers 100% of the entire surface area of ​​the porous carbon material, the porous carbon material becomes completely covered with sulfur, thus reducing the wettability of the electrolyte and reducing contact with the conductive material included in the electrode. Therefore, electrons cannot be transferred and cannot participate in the reaction.

[058] Next, an example of a production method will be described. Petition 870250085671, dated 09 / 22 / 2025, pp. 63 / 94 12 / 38 sulfur and carbon composite. In the production method according to one embodiment of the present disclosure, the sulfur and carbon composite can be produced by a compounding method including the steps of (S1) mixing a porous carbon material and a sulfur-based material, and (S2) compounding the mixture.

[059] In step (S1), mixing can be carried out using an agitation device according to one embodiment, in order to increase the degree of mixing between the sulfur-based material and the porous carbon material. Here, the mixing time and speed can also be selectively adjusted according to the content and conditions of the raw materials.

[060] In step (S2), the composition method is not particularly limited in the present disclosure and, for example, a method such as dry composition or wet composition, such as spray coating, can be used. For example, a method can be used in which the mixture of sulfur and carbon materials obtained after mixing is pulverized by ball grinding and then placed in an oven of about 120 °C to 160 °C for about 20 minutes to 1 hour (h) so that the inner and outer surfaces of the carbon material can be uniformly coated with molten sulfur.

[061] The sulfur-carbon composite produced by the production method described above has a structure with a high specific surface area, a large amount of supported sulfur, and an improved sulfur utilization rate, so that not only is the electrochemical reactivity of sulfur improved, but also the accessibility and contactability of the electrolyte are improved. In this way, the capacity and service life characteristics of the lithium-sulfur battery can be improved.

[062] In one embodiment of the present disclosure, the sulfur and carbon composite may have a density of about 1.5 g / cm3 or more. For example, the sulfur and carbon composite may have a density of about 1.5 g / cm3 to 3.0 Petition 870250085671, dated 09 / 22 / 2025, pp. 64 / 94 13 / 38 g / cm3. Alternatively, the sulfur and carbon composite may have a density of about 1.8 g / cm3 to 2.5 g / cm3, about 1.8 g / cm3 to 2.1 g / cm3, or about 1.9 g / cm3 to 2.1 g / cm3, for example, about 2.0 g / cm3. Electrode Thickness and Equation 1

[063] In an electrode that includes a sulfur-based material as an active material, an electrode active material layer can be formed using the sulfur-based material, a conductive material, a binder, etc. That is, an electrode having a high-density electrode active material layer can be implemented by including the sulfur-based material structurally independently of the conductive material. In the present disclosure, since a sulfur-based material is supported on a porous carbon material and such a sulfur-carbon composite is used as an active material, a low density can be implemented in the electrode active material layer compared to the electrode that includes the sulfur-based material structurally independently of the conductive material.

[064] Therefore, the present disclosure provides an electrode using the sulfur and carbon composite described above, in which, on the electrode, a layer of electrode active material is formed by bonding the composite with a binder, and the weight ratio of a current collector is relatively reduced to increase the density of the electrode active material layer, for example, the density of the sulfur and carbon composite on the electrode.

[065] To this end, the thickness of the current collector can be limited to about 9 μm or less, but the reason for limiting the thickness of the current collector in this way is not limited to this.

[066] For example, in one embodiment of the present disclosure, the electrode active material layer may have a porosity of about 60% by volume to 85% by volume. For example, the porosity of the electrode active material layer Petition 870250085671, dated 09 / 22 / 2025, pp. 65 / 94 14 / 38 can be approximately 60% by volume to 80% by volume, 65% by volume to 80% by volume, 70% by volume to 80% by volume, or 75% by volume to 80% by volume, for example, approximately 78% by volume.

[067] In this descriptive report, the term “porosity” refers to the ratio of the volume occupied by pores to the total volume of a given structure, uses % by volume as its unit and can be used interchangeably with terms such as pore ratio and void ratio. Porosity can be measured according to the ISO 15901:2019 method known in the art.

[068] In one embodiment of the present disclosure, the porosity of the active electrode material layer can be measured, for example, by mercury intrusion porosimetry (Hg porosimeter) and can be measured using, for example, a mercury porosimeter (Micromeritics AUTOPORE V). Furthermore, the porosity of the positive electrode active material layer can also be measured using a BET (Brunauer-Emmett-Teller) measurement method using an adsorption gas, such as nitrogen, and can be measured using, for example, an analytical device from the BELSORP series of BEL Japan, for example, mini II, but the present disclosure is not limited to this. The porosity measured by this method can mean the total volume of pores formed in the positive electrode active material layer.Furthermore, porosity can also be measured by calculating the actual density of the materials that make up the active material layer of the positive electrode, the apparent density of the prepared active material layer of the positive electrode, and the thickness of the positive electrode. For example, porosity can be calculated as a value of [(actual density - apparent density) / actual density] X 100(%) of the active material layer of the positive electrode.

[069] In the electrode according to an embodiment of the present disclosure, the value based on the following equation 1 can satisfy 90 cm2 / mAh or more. [Equation 1] Petition 870250085671, dated 09 / 22 / 2025, pp. 66 / 94 15 / 38 electrode weight — current collector weight) 1 current collector weight amount of electrode charge

[070] In equation 1 above, the electrode weight unit and the current collector weight unit are grams (g), and the electrode charge quantity is the amount of sulfur charge on the electrode and its unit is mAh / cm2.

[071] In one embodiment of the present disclosure, since the current collector does not affect the expression of the electrode capacity, as the weight ratio of the current collector decreases relative to the total weight of the electrode, i.e., the weight ratio of the components (e.g., the electrode active material layer) excluding the current collector increases relative to the total weight of the electrode, an advantageous effect can be exhibited in the implementation of a high energy density.

[072] In one embodiment of the present disclosure, the “amount of charge of the electrode” is the amount of active material per unit area of ​​the electrode and can be converted, for example, into the value of the capacitance of the electrode per unit area of ​​the electrode and can be expressed as a value of mAh / cm2. Here, the greater the amount of charge of the electrode, the greater the content of the active material in the electrode. Consequently, the total weight of the electrode can be increased. Thus, the weight increase caused by the charge can be corrected by dividing by the value of the amount of charge of the electrode in equation 1 above.

[073] Therefore, a higher value based on equation 1 above may indicate an electrode suitable for use in an electrochemical device having a high energy density.

[074] For example, according to one embodiment of the present disclosure, an electrode can be provided in which the value based on equation 1 above is about 90 cm2 / mAh or more. For example, an electrode can be provided in which the value based on equation 1 above is about 90 cm2 / mAh to 200 cm2 / mAh, 90 Petition 870250085671, dated 09 / 22 / 2025, pp. 67 / 94 16 / 38 cm² / mAh to 180 cm² / mAh, 90 cm² / mAh to 160 cm² / mAh, or 90 cm² / mAh to 150 cm² / mAh. According to one embodiment, an electrode can be provided in which the value based on equation 1 above is 95 cm² / mAh to 150 cm² / mAh, 100 cm² / mAh to 145 cm² / mAh, or 105.5 cm² / mAh to 142.5 cm² / mAh. When the electrode has the value of equation 1 described above, an advantageous effect can be displayed in the implementation of an electrode and an electrochemical device with a high energy density, but the present invention is not thus limited.

[075] For the reasons described above, as the thickness of the current collector decreases, an advantageous effect can be exhibited in the implementation of the high electrode energy. According to one embodiment of the present disclosure, the thickness of the current collector can be, for example, about 9 μm or less, for example, about 1 μm to 9 μm, 2 μm to 9 μm, 3 μm to 8.5 μm, 4 μm to 8.5 μm, 5 μm to 8.5 μm, 5.5 μm to 8.5 μm, 6 μm to 8 μm, 5.5 μm to 7 μm or 5.5 μm to 6.5 μm. When the thickness of the current collector is within the range described above, the weight of the electrode does not increase significantly relative to the electrode capacity. Thus, an advantageous effect in the implementation of high energy density can be exhibited, and an advantageous effect can also be exhibited in terms of preventing the problem of damage to the current collector, such as breakage, but the present disclosure is not limited to this.

[076] In one embodiment of the present disclosure, the “thickness” of the current collector can be a value measured by means of a known thickness value of the current collector to be used or a value measured using a known thickness measuring device. As for the thickness measuring device for the measurement, for example, a thickness measuring device from Mitutoyo Corporation can be used. Alternatively, the thickness of the current collector can be measured by means of an electron microscopic photograph in the cross-section of the electrode. Petition 870250085671, dated 09 / 22 / 2025, pp. 68 / 94 17 / 38

[077] As described above, in one embodiment of the present disclosure, when the amount of electrode charge is too high, a phenomenon may occur in which no significant effect is shown on improving the energy density of the battery, even when the thickness of the current collector is within the range described above. To this end, in one embodiment of the present disclosure, when the amount of electrode charge is equal to or less than a certain level, the current collector with the thickness described above may be used.

[078] In one embodiment of the present disclosure, the electrode charge quantity can be, for example, about 10 mAh / cm2 or less. For example, the electrode charge quantity can be from about 0.5 mAh / cm2 to 10 mAh / cm2.

[079] In another embodiment of the present disclosure, the electrode charge quantity may be, for example, about 9 mAh / cm2 or less, 8 mAh / cm2 or less, 7 mAh / cm2 or less, 6 mAh / cm2 or less or 5 mAh / cm2 or less. Alternatively, the electrode charge quantity may be, for example, about 4.5 mAh / cm2 or less, 4.0 mAh / cm2 or less or 3.5 mAh / cm2 or less.

[080] In a further embodiment of the present disclosure, the amount of charge on the electrode may be, for example, about 1 mAh / cm2a 5 mAh / cm2, 1.5 mAh / cm2a 5 mAh / cm2, 2 mAh / cm2a 5 mAh / cm2, 2.1 mAh / cm2a 5 mAh / cm2, 2.2 mAh / cm2a 5 mAh / cm2, 2.3 mAh / cm2a 5 mAh / cm2 or 2.3 mAh / cm2a 5.0 mAh / cm2, 2.3 mAh / cm2a 4.5 mAh / cm2, 2.3 mAh / cm2a 4.0 mAh / cm2, or 2.3 mAh / cm2a 3.5 mAh / cm2.

[081] In one embodiment of the present disclosure, the “amount of charge on the electrode” indicates the amount of sulfur (S) charge on the electrode and can be measured according to a known method for measuring the amount of sulfur charge on the electrode. For example, the amount of charge on the electrode can be a value calculated from the total weight of sulfur (S) included as the active material on the electrode. Here, the weight of sulfur on the electrode can also be measured from the Petition 870250085671, dated 09 / 22 / 2025, pp. 69 / 94 18 / 38 The amount of active electrode material introduced during the manufacturing step, or it can be measured by means of thermogravimetric analysis (TGA) on the electrode after manufacturing. Meanwhile, in obtaining the electrode by disassembling a manufactured lithium-sulfur battery, the electrode is obtained by disassembling the charged lithium-sulfur battery under an inert atmosphere, and then the electrode is washed using an appropriate washing solvent and dried. Then, by means of thermogravimetric analysis (TGA) of the result obtained by scraping the layer of active electrode material, the sulfur content (S) derived from the active material can be measured for calculation, but the measurement method is not limited to this. Here, the amount of sulfur charge can be calculated using the actually measured capacity (1,200 mAh / gs) of sulfur from the sulfur weight obtained above. Electrode Active Material Layer

[082] The electrode, according to one embodiment of the present disclosure, may contain a large amount of active material. The electrode may contain a large amount of active material to solve a problem where the increase in energy density is not proportional to the increase in electrode density.

[083] For example, in the electrode, the content of the sulfur-based material in the electrode active material layer may be about 65% by weight or more. For example, the content of the sulfur-based material in the electrode active material layer may be about 65% by weight to 99% by weight, 65% by weight to 95% by weight, 65% by weight to 90% by weight, 65% by weight to 85% by weight, 70% by weight to 85% by weight, 70% by weight to 80% by weight, 70% by weight to 75% by weight, 72.5% by weight to 75% by weight or 70% by weight to 72.5% by weight, but the present disclosure is not limited to this. In the present disclosure, when the sulfur-based material content in the electrode active material layer is within the range described above, there may be an advantageous effect of increasing the active material capacity in the electrode, while maintaining the conductive carbon material content and the binder content at [value]. Petition 870250085671, dated 09 / 22 / 2025, pp. 70 / 94 19 / 38 a certain level, thus obtaining high electrical conductivity and / or excellent bonding strength between active materials, but the present disclosure is not limited to this.

[084] In one embodiment of the present disclosure, the sulfur-based material content in the electrode active material layer can be calculated from the weight of the sulfur-based material introduced relative to the total weight of the electrode materials added during the manufacturing step of the electrode active material layer. Alternatively, based on the manufactured electrode, the content can be calculated from a value obtained by analyzing the sulfur-based material content in the total weight of the electrode active material layer, excluding the weight of the current collector in the electrode. Here, for the method of analyzing the sulfur-based material content in the electrode active material layer, see those described above in the method of measuring the amount of charge. Chain Collector

[085] According to one aspect of the present disclosure, the current collector includes aluminum (Al).

[086] For example, in one embodiment of the present disclosure, the current collector is a current collector that can be used for a positive electrode and may include aluminum.

[087] In another embodiment of the present disclosure, the current collector can be made only of aluminum (Al).

[088] In another embodiment of the present disclosure, the current collector may include aluminum and may further include current collector components used for the positive electrode. For example, the current collector may include stainless steel, nickel, titanium, calcined carbon, silver, or two or more types of these components, along with aluminum.

[089] In one embodiment of the present disclosure, when the current collector also includes a component other than aluminum, for example, it is possible Petition 870250085671, dated 09 / 22 / 2025, pp. 71 / 94 20 / 38 Use aluminum whose surface is rolled with stainless steel, stainless steel whose surface is rolled with aluminum, or aluminum whose surface is treated with nickel, titanium, carbon, silver, or two or more of these components.

[090] In one embodiment of the present disclosure, in order to improve the bond strength with the active electrode material layer formed on the surface of the current collector, it is possible to use the current collector having a surface on which fine irregularities are formed, but the present disclosure is not limited to this.

[091] In one embodiment of the present disclosure, the current collector can be used in various forms, such as, for example, a film, a plate, a sheet, a net, a porous body, a foam and a non-woven fabric and, as an example, the current collector can be an aluminum sheet.

[092] Next, other electrode components according to an aspect of the present disclosure will be described in detail.

[093] In one embodiment of the present disclosure, the binder performs the function of improving the adhesion between particles of the active material and the adhesive strength between the active material and the current collector. Examples thereof may include polyvinylidene fluoride (PVDF), vinylidene fluoride hexafluoropropylene copolymer (PVDF-co-HFP), polyvinyl alcohol, polyacrylonitrile, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, polytetrafluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene monomer rubber (EPDM rubber), sulfonated EPDM, styrene-butadiene rubber (SBR), fluorinated rubber or various copolymers thereof, and among these, one type may be used alone or a mixture of two or more types may be used.The binder resin can be included in an amount of about 1% by weight to 30% by weight, for example, 1% by weight to 20% by weight, or 1% by weight to 10% by weight relative to the total weight of the active material layer of the positive electrode. Petition 870250085671, dated 09 / 22 / 2025, pp. 72 / 94 21 / 38

[094] In one embodiment of the present disclosure, the active electrode material layer may also include other additives, such as a conductive material, in addition to the sulfur and carbon composite and the binder.

[095] The conductive material is used to impart, for example, conductivity to the electrode and may be used without specific limitation, provided it has electronic conductivity without causing a chemical change in the battery to be formed. Examples thereof may include graphite, such as natural graphite or artificial graphite; carbon-based materials, such as carbon black, acetylene black, Ketjen black, channel black, furnace black, lamp black, thermal black, carbon fiber and carbon nanotubes; metallic powder or metallic fiber, such as copper, nickel, aluminum and silver; conductive whiskers, such as zinc oxide and potassium titanate; conductive metal oxides, such as titanium oxide; and conductive polymers, such as polyphenylene derivatives, and among these, one type may be used alone or a mixture of two or more types may be used.When conductive material is used, the conductive material can generally be included in an amount of about 1% by weight to 30% by weight, for example, 1% by weight to 20% by weight, or 1% by weight to 10% by weight relative to the total weight of the positive electrode active material layer.

[096] In one embodiment of the present disclosure, the electrode active material layer may also include other active materials besides the sulfur and carbon composite described above.

[097] Here, other active materials that may be included additionally may not be particularly limited, provided they can be used as active materials in, for example, a secondary lithium battery. Examples of such active materials may include: lithium transition metal oxide; lithium iron and metal phosphate; lithium-nickel-manganese-cobalt oxide; an oxide obtained by replacing a portion of lithium-nickel-manganese-cobalt oxide with another metal. Petition 870250085671, dated 09 / 22 / 2025, pp. 73 / 94 22 / 38 transition metals; or two or more of these, but without limitation. For example, examples of the active positive electrode material may include: layered compounds, such as lithium cobalt oxide (LiCoO2) and lithium nickel oxide (LiNiO2) or compounds substituted with one or more transition metals; lithium manganese oxide of a chemical formula Li1+xMn2-xO4 (where x is 0 to 0.33) such as LiMnO3, LiMn2O3 and LiMnO2; lithium copper oxide (Li2CuO2); vanadium oxide, such as LiV3O8, LV3O4, V2O5 and Cu2V2O7; lithium nickel oxide of the Ni site type represented by a chemical formula LíNíi-xMxO2 (where M = Co, Mn, Al, Cu, Fe, Mg, B or Ga, ex = 0.01 to 0.3); Lithium manganese composite oxide represented by a chemical formula LiMn2xMxO2 (where M = Co, Ni, Fe, Cr, Zn or Ta, ex = 0.01 to 0.1) or Li2MnaMO8 (where M = Fe, Co, Ni, Cu or Zn); lithium metal phosphate LiMPO4 (where M = Fe, CO, Ni or Mn);lithium-nickel-manganese-cobalt oxide Li1+x(NiaCobMnc)1-xO2 (x = 0 to 0.03, a = 0.3 to 0.95, b = 0.01 to 0.35, c = 0.01 to 0.5, and a+b+c=1); an oxide Lia[NibCocMndAle]1fM1fO2 in which a portion of the lithium-nickel-manganese-cobalt oxide is replaced by aluminum (M1 is at least one type selected from the group consisting of Zr, B, W, Mg, Ce, Hf, Ta, La, Ti, Sr, Ba, F, P and S, 0.8; <a<1,2, 0,5<b<0,99, 0<c<0,5, 0<d<0,5, 0,01<e<0,1 e 0<f<0,1); um óxido li1+x(niacobmncmd)1-xo2 em que uma parte de lítio-níquel-manganês-cobalto é substituído por outro metal transição (x="0" a 0,03, 0,95, b="0,01" 0,35, c="0,01" 0,5, d="0,001" a+b+c+d="1," m qualquer selecionado do grupo consiste fe, v, cr, ti, w, ta, mg mo); composto dissulfeto; fe2(moo4)3, mas sem limitação.Lithium-Sulfur Battery

[098] A lithium-sulfur battery, according to another aspect of the present disclosure, includes a positive electrode, a negative electrode, a separator interposed between the positive and negative electrodes, and an electrolyte. At least one of the positive and negative electrodes is the electrode described above.

[099] In one embodiment of the present disclosure, the positive electrode of Petition 870250085671, dated 09 / 22 / 2025, pp. 74 / 94 23 / 38 lithium-sulfur battery may have the electrode described above. For example, the positive electrode is an electrode that includes a current collector and a layer of active electrode material located on at least one side of the current collector. The active electrode material layer includes a sulfur-carbon composite and a binder, and the sulfur-carbon composite includes a porous carbon material and a sulfur-based material. The current collector includes aluminum (Al) and may have a thickness of about 9 μm or less.

[0100] In one embodiment of the present disclosure, the unitary structure of the positive electrode / separator / negative electrode may be referred to as an electrode assembly, and for the electrode assembly, for example, the negative electrode, the positive electrode and the separator interposed between these electrodes may be stacked to form a stacked or stacked / folded structure or may be rolled to form a jelly roll type structure. Furthermore, when the jelly roll type structure is formed, a separator may be additionally arranged on the outside so as to prevent the negative electrode and the positive electrode from coming into contact with each other.

[0101] In one embodiment of the present disclosure, the negative electrode will be described in detail when the positive electrode is the electrode described above.

[0102] The negative electrode may have a structure in which a layer of negative electrode active material is formed on one or both surfaces of a long, shell-shaped negative electrode current collector. The negative electrode active material layer may include a negative electrode active material and a binder resin. In addition, the negative electrode active material layer may also include a conductive material, as required.

[0103] For example, the negative electrode can be manufactured by a method of applying a fluid negative electrode paste to one or both surfaces of a sheet-shaped negative electrode current collector. Petition 870250085671, dated 09 / 22 / 2025, pp. 75 / 94 24 / 38 long, removing the solvent from the negative electrode fluid paste by means of a drying process and performing roller pressing. The negative electrode fluid paste is prepared by dispersing the negative electrode active material, the conductive material and the binder in a solvent, such as dimethyl sulfoxide (DMSO), isopropyl alcohol, N-methylpyrrolidone (NMP), acetone or water. Meanwhile, a negative electrode including an uncoated portion can be manufactured by a method in which, during the application of the negative electrode fluid paste, the negative electrode fluid paste is not applied to a part of the negative electrode current collector region, for example, one end of the negative electrode current collector.

[0104] The active negative electrode material may include a material through which lithium (Li) ions can be reversibly intercalated or deintercalated, a material capable of reversibly forming a lithium-containing compound upon reacting with lithium ions, a lithium metal, or a lithium alloy. The material through which lithium ions can be reversibly intercalated or deintercalated may be, for example, crystalline carbon, amorphous carbon, or a mixture thereof, and examples thereof may include artificial graphite, natural graphite, graphite-coated carbon fiber, amorphous carbon, soft carbon, and hard carbon, but not limited to.

[0105] The material capable of reversibly forming a lithium-containing compound by reaction of lithium ions may be, for example, tin oxide, titanium nitrate or a silicon-based compound.

[0106] The lithium alloy may be, for example, an alloy of lithium (Li) and a metal selected from the group consisting of sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), francium (Fr), beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), radium (Ra), aluminum (Al) and tin (Sn). For example, the active negative electrode material may be lithium metal and may have the form of, for example, a thin film of lithium metal or lithium metal powder. Petition 870250085671, dated 09 / 22 / 2025, pp. 76 / 94 25 / 38

[0107] The silicon-based compound may be Si, a Si-Me alloy (where Me is at least one type selected from the group consisting of Al, Sn, Mg, Cu, Fe, Pb, Zn, Mn, Cr, Ti and Ni), SiOy (where 0 <y<2), um compósito de si-c ou uma combinação dos mesmos, e pode ser, por exemplo, sioy (em que 0<y<2). uma vez o composto à base silício tem alta capacidade teórica, quando é incluído como material ativo eletrodo negativo, as características podem ser melhoradas.

[0108] Regarding the negative electrode current collector, for example, copper, stainless steel, aluminum, nickel, titanium, calcined carbon, copper or stainless steel whose surface is treated with carbon, nickel, titanium, silver, etc., an aluminum-cadmium alloy, etc., can be used. The negative electrode current collector can generally have a thickness of about 3 μm to 500 μm, and, as in the positive electrode current collector, fine irregularities can be formed on the surface of the current collector to increase the bonding strength of the negative electrode active material. For example, the negative electrode current collector can be used in various forms, such as a film, a sheet, a foil, a mesh, a porous body, a foam, and a non-woven fabric.

[0109] The binder plays a role in improving the adhesion between particles of the negative electrode active material and the adhesive strength between the negative electrode active material and the negative electrode current collector. Examples thereof may include polyvinylidene fluoride (PVDF), vinylidene fluoride-hexafluoropropylene copolymer (PVDF-co-HFP), polyvinyl alcohol, polyacrylonitrile, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, polytetrafluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene monomer rubber (EPDM rubber), sulfonated EPDM, styrene-butadiene rubber (SBR), fluorinated rubber and various copolymers thereof, and among them, one type may be used alone or a mixture of two or more types may Petition 870250085671, dated 09 / 22 / 2025, pp. 77 / 94 26 / 38 to be used. The binder may be included in an amount of about 1% by weight to 30% by weight, for example, about 1% by weight to 20% by weight, or 1% by weight to 10% by weight relative to the total weight of the negative electrode active material layer.

[0110] The conductive material that is included as required is used to impart conductivity to the negative electrode and may be used without specific limitation, provided it has electronic conductivity without causing a chemical change in the battery to be formed. Examples thereof may include: graphite, such as natural graphite or artificial graphite; carbon-based materials, such as carbon black, acetylene black, Ketjen black, canal black, furnace black, lamp black, thermal black, carbon fiber and carbon nanotubes; metal powder or metal fiber, such as copper, nickel, aluminum and silver; conductive whiskers, such as zinc oxide and potassium titanate; conductive metal oxides, such as titanium oxide; and conductive polymers, such as polyphenylene derivatives, and among these, one type may be used alone or a mixture of two or more types may be used.When conductive material is used, the conductive material can generally be included in an amount of about 1% by weight to 30% by weight, for example, about 1% by weight to 20% by weight, or 1% by weight to 10% by weight relative to the total weight of the negative electrode active material layer.

[0111] The separator is arranged in the electrode assembly so that it is interposed between the negative and positive electrodes. The separator separates the negative electrode from the positive electrode and provides a path for lithium ion movement, and may be used without specific limitation, provided it is generally used as a separator in a secondary lithium battery. For example, regarding the separator, a porous polymer film, for example, a porous polymer film made of a polyolefin-based polymer, such as ethylene homopolymer, propylene homopolymer, ethylene / butene copolymer, copolymer of Petition 870250085671, dated 09 / 22 / 2025, pp. 78 / 94 27 / 38 ethylene / hexene and ethylene / methacrylate copolymer, or a laminated structure of two or more layers thereof, may be used. In addition, a conventional porous nonwoven fabric, for example, a nonwoven fabric made of high-melting-point fiberglass, polyethylene terephthalate fiber, etc., may also be used. Furthermore, a coated separator containing ceramic components or polymeric materials may also be used to ensure heat resistance or mechanical strength.

[0112] In one embodiment of the present disclosure, the lithium-sulfur battery can be provided in a form in which the electrode assembly having, for example, a constituent unit of the positive electrode, the negative electrode and the separator, is housed in a battery casing together with the electrolyte.

[0113] In one embodiment of the present disclosure, with respect to the battery casing, any suitable casing may be selected without specific limitation, provided that it is a type commonly used in the present technical field, such as, for example, a pouch type, a metal can type, a cylindrical type, a stack type or a coin type.

[0114] In one embodiment of the present disclosure, the lithium-sulfur battery may be a pouch-type, coin-type or cylindrical battery, and may be, for example, a pouch-type battery, but the present disclosure is not so limited.

[0115] In one embodiment of the present disclosure, as to the electrolyte, for example, an organic liquid electrolyte, an inorganic liquid electrolyte, a solid polymer electrolyte, a gel-type polymer electrolyte, a solid inorganic electrolyte, a molten inorganic electrolyte, etc., can be used, and the type thereof is not particularly limited.

[0116] In one embodiment of the present disclosure, the electrolyte may include a lithium salt.

[0117] In another embodiment of the present development, the electrolyte may include Petition 870250085671, dated 09 / 22 / 2025, pp. 79 / 94 28 / 38 a lithium salt and a non-aqueous solvent.

[0118] In a further embodiment of the present disclosure, the electrolyte may include a lithium salt, a non-aqueous solvent and additives.

[0119] Lithium salt can be used without any specific limitation, provided it is a compound capable of supplying lithium ions to be used in the secondary lithium battery. For example, regarding lithium salt, LiPF6, LiCO4, LiAsF6, LiBF4, LiSbF6, LiAlO4, LiAlCl4, UCF3SO3, UC4F9SO3, LiN(C2F5SO3)2, LiN(C2F5SO2)2, LiN(CF3SO2)2, LiCl, LiI, LiB(C2O4)2, etc. can be used. It is desirable to use a lithium salt concentration within a range of about 0.1 M to 5.0 M, for example, about 0.1 M to 3.0 M. When the lithium salt concentration is within the above range, provided the electrolyte has appropriate conductivity and viscosity, excellent electrolyte performance can be exhibited, and lithium ions can be moved effectively.

[0120] In one embodiment of the present disclosure, the lithium salt may contain LiTFSI.

[0121] Non-aqueous solvents may be used without any specific limitation, provided they can serve as a medium through which ions involved in the electrochemical reaction of the battery are mobile. For example, regarding non-aqueous solvents, it is possible to use ester-based solvents such as methyl acetate, ethyl acetate, γ-butyrolactone and ε-caprolactone; ether-based solvents such as dibutyl ether or tetrahydrofuran; ketone-based solvents such as cyclohexanone; aromatic hydrocarbon-based solvents such as benzene and fluorobenzene; carbonate-based solvents such as dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), ethylene carbonate (EC) and propylene carbonate (PC); alcohol-based solvents such as ethyl alcohol and isopropyl alcohol; nitriles, such as R-CN (R is a linear, branched or cyclic hydrocarbon group C2 to C20 and may include a double bond, an aromatic ring Petition 870250085671, dated 09 / 22 / 2025, pp. 80-94 29 / 38 or an ether linkage); amides such as dimethylformamide; dioxolanes, such as 1,3-dioxolane; or sulfolanes.

[0122] Meanwhile, in one embodiment of the present disclosure, the electrolyte may include a heterocyclic compound containing an oxygen atom or a sulfur atom in terms of forming a protective polymer film capable of suppressing the generation of lithium dendrites and decreasing electrolyte decomposition and side reactions on the surface of the lithium-based metal. The heterocyclic compound may be a 3- to 15-membered heterocyclic compound, for example, a 3- to 7-membered or 5- to 6-membered heterocyclic compound.The heterocyclic compound may be a heterocyclic compound substituted or unsubstituted by at least one type selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a cyclic alkyl group having 3 to 8 carbon atoms, an aryl group having 6 to 10 carbon atoms, a halogen group, a nitro group (-NO2), an amine group (-NH2), and a sulfonyl group (-SO2); or a polycyclic compound of at least one type selected from the group consisting of a cyclic alkyl group having 3 to 8 carbon atoms and an aryl group having 6 to 10 carbon atoms, and a heterocyclic compound. When the heterocyclic compound is a heterocyclic compound substituted by an alkyl group having 1 to 4 carbon atoms, radicals may be stabilized and side reactions between additives and the electrolyte may be suppressed.Furthermore, in the case of a heterocyclic compound substituted with a halogen or nitro group, a functional protective film can be formed on the surface of the lithium-based metal. This functional protective film is a stable and compact type of protective film that allows for uniform deposition of the lithium-based metal and suppresses side reactions between the polysulfide and the lithium-based metal.

[0123] The heterocyclic compound may include, for example, at least one type selected from the group consisting of furan, 2-methylfuran, 3-methylfuran, 2-ethylfuran, 2-propylfuran, 2-butylfuran, 2,3-dimethylfuran, 2,4-dimethylfuran, 2,5 Petition 870250085671, dated 09 / 22 / 2025, pp. 81 / 94 30 / 38 dimethylfuran, pyran, 2-methylpyran, 3-methylpyran, 4-methylpyran, benzofuran, 2-(2-nitrovinyl)furan, thiophene, 2-methylthiophene, 2-ethylthiophene, 2-propylthiophene, 2-butylthiophene, 2,3-dimethylthiophene, 2,4-dimethylthiophene and 2,5-dimethylthiophene, and may include, for example, at least one type selected from the group consisting of 2-methylfuran and 2-methylthiophene.

[0124] Meanwhile, in one embodiment of the present disclosure, with respect to the non-aqueous electrolyte solvent, an ether-based solvent may be included in order to improve the battery's charge / discharge performance. Such ether-based solvents include cyclic ethers (e.g., 1,3-dioxolane, tetrahydrofuran, tetrahydropyran, etc.), linear ether compounds (e.g., 1,2-dimethoxyethane, etc.), and low-viscosity fluorinated ethers (e.g., 1H,1H,2'H,3Hdecafluorodipropyl ether, 2,2,2-trifluoroethyl difluoromethyl ether, 1,2,2,2-tetrafluoroethyl trifluoromethyl ether, 1,1,2,3,3,3-hexafluoropropyl difluoromethyl ether, 1H,1H,2'H,3Hdecafluorodipropyl ether, 2,2,2-trifluoroethyl pentafluoroethyl ether, and 1H,1H,2'Hperfluorodipropyl ether), and a mixture of one or more of these types may be included as a non-aqueous solvent.

[0125] In one embodiment of the present disclosure, the non-aqueous solvent may include a mixture of 2-methylfuran and dimethoxyethane.

[0126] In one embodiment of the present disclosure, the non-aqueous solvent may include a mixture of 2-methylfuran and dimethoxyethane in a volume ratio of about 5:1 (v / v) to 1:5 (v / v), for example, about 1:1 (v / v) to 1:5 (v / v).

[0127] In one embodiment of the present disclosure, the additive may be used without specific limitation, provided that it is an additive that can be used in lithium-sulfur batteries for the purpose of improving battery life characteristics, suppressing battery capacity decline, and improving battery discharge capacity. The additive may be included in an amount of about 0.1% by weight to 10% by weight, for example, 0.1% by weight to 5% by weight relative to the total weight of the electrolyte. Petition 870250085671, dated 09 / 22 / 2025, pp. 82 / 94 31 / 38

[0128] In one embodiment of the present disclosure, the additive may include, for example, a nitrogen compound, for example, LiNOa.

[0129] Meanwhile, in one embodiment of the present disclosure, in the lithium-sulfur battery of the present disclosure, the ratio (El / S) of the total weight of the electrolyte to the total weight of the sulfur element (S) in the positive electrode can be, for example, 3.5 g / g or less, for example, 3.3 g / g or less or 3.2 g / g or less. Furthermore, in the lithium-sulfur battery, the ratio (El / S) of the total weight of the electrolyte to the total weight of the sulfur element (S) in the positive electrode can be about 2.0 g / g 3.5 g / g, for example, 2.0 g / g 3.0 g / g or 2.5 g / g 3.0 g / g. When the sulfur and carbon composite according to the present disclosure is used, it is also possible to implement a lithium-sulfur battery with an El / S ratio within the range described above, and thus the effect of improving energy density can be exhibited.Meanwhile, regarding lithium-sulfur batteries using a sulfur-carbon compound, it is also possible to implement a battery having an El / S ratio greater than the range described above, but the present disclosure is not so limited.

[0130] In one embodiment of the present disclosure, the El / S ratio can be calculated by measuring the weight of sulfur in the sulfur-based material introduced into the positive electrode and by measuring the weight of the injected electrolyte during the manufacturing step of the lithium-sulfur battery.

[0131] In one embodiment of the present disclosure, the El / S ratio can be measured based on the lithium-sulfur battery as a finished manufactured product. The weight of sulfur in the positive electrode is measured according to the method described above for measuring the amount of sulfur charge in the positive electrode. Then, in a charged state, for example, SOC (State of Charge) 100%, after the battery is disassembled and the electrolyte is extracted from the positive electrode, the negative electrode, the separator, and the casing, the weights of all remaining components are measured. Then, a value is obtained by subtracting the weight of the remaining components after Petition 870250085671, dated 09 / 22 / 2025, pp. 83 / 94 32 / 38 the extraction of the finished product weight of the lithium-sulfur battery, which is then considered as the weight of the electrolyte.

[0132] In one embodiment of the present disclosure, the lithium-sulfur battery can be a battery having a high energy density and can be a battery having an energy density of, for example, 350 Wh / kg or more.

[0133] For example, the energy density of lithium-sulfur batteries can be around 350 Wh / kg to 450 Wh / kg, but without limitation.

[0134] In one embodiment of the present disclosure, the energy density of the lithium-sulfur battery can be calculated according to the following equation after the discharge capacity is measured by performing a 1.8 V discharge at a rate of 0.5 C in a DC (constant current) mode at 25 °C and charging at 2.5 V with a constant current of 0.2 C.

[0135] Energy density = [(Discharge capacity X Operating voltage)] / (Cell weight)

[0136] Furthermore, according to a further aspect of the present disclosure, a battery module including the lithium-sulfur battery as a unitary battery is provided.

[0137] The battery module can be used as a power source for medium to large devices that require, for example, high temperature stability, long cycle characteristics and high capacity characteristics.

[0138] Examples of medium to large-sized devices may include a power tool powered and driven by an electric motor; electric cars, including electric vehicles (EVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), etc.; electric two-wheeled vehicles, including an electric bicycle (E-bike) and an electric scooter (Escooter); an electric golf cart; and an energy storage system, but not limited to.

[0139] The present revelation will now be described in detail with Petition 870250085671, dated 09 / 22 / 2025, pages 84 / 94 33 / 38 reference to Examples, drawings etc. Lithium-Sulfur Battery Manufacturing Positive Electrode Manufacturing

[0140] A thin film of aluminum (Al foil) was prepared as a current collector, and a fluid electrode paste was applied to a surface of the prepared current collector and dried to fabricate an electrode for a positive electrode. The fluid electrode paste was prepared by mixing 96% by weight of sulfur and carbon composite (S8:CNT = 75:25) and 4% by weight of poly(acrylic acid) (PAA).

[0141] In Tables 1 and 2 below, the thickness of the current collector used for electrode fabrication, the amount of sulfur (S8) charge on the electrode, and the value based on the following equation 1 are described. [Equation 1] (weight of the electrode — weight of the current collector) 1 weight of the current collector amount of charge on the electrode

[0142] In equation 1 above, the electrode weight unit and the current collector weight unit are grams (g), and the electrode charge quantity is the amount of sulfur charge on the electrode and its unit is mAh / cm2. Lithium-Sulfur Battery Manufacturing

[0143] The electrode manufactured above was used as a positive electrode, and a lithium metal with a thickness of 60 μm was prepared as a negative electrode.

[0144] The positive electrode and the negative electrode were positioned facing each other, and a polyethylene separator (Celgard, PE12) with a thickness of 12 μm was interposed between the electrodes in order to prepare an electrode array.

[0145] The prepared electrode assembly was housed in a pouch-type casing, and an electrolyte was injected at an El / S ratio of 2.5 g / g to manufacture a lithium-sulfur battery. The electrolyte was obtained by dissolving 0.75 M of salt of Petition 870250085671, dated 09 / 22 / 2025, pages 85 / 94 34 / 38 lithium (LiTFSI) and 3% by weight of lithium nitrate (LINO3) in an organic solvent, and the organic solvent was obtained by mixing 2-methylfuran (2-MeF) and dimethoxyethane (DME) in a volume ratio of 3:7.

[0146] In Tables 1 and 2 below, and Figure 1, the weight ratio of the positive electrode current collector (Al foil) in the manufactured bag-type battery is described. Performance Evaluation of Lithium-Sulfur Batteries Energy Density

[0147] Each of the lithium-sulfur batteries manufactured above was discharged to 1.8 V in a constant current (DC) mode at a rate of 0.5 C at room temperature (25 °C) and then charged to 2.5 V with constant current (DC) at a rate of 0.3 C. Then, the discharge capacity (mAh / g (weight of sulfur)) per weight of sulfur was measured.

[0148] Meanwhile, from the measured discharge capacity, the energy density was measured according to the following equation 2. Then, when Comparative Example 1 (Table 1) and Comparative Example 4 (Table 2) for respective load quantities, each using a current collector with a thickness of 20 μm, are used as a reference, the relative energy density values ​​are described in Tables 1 and 2 and Figure 2. [Equation 2] Energy density (Wh / kg) = {[(Discharge capacity (mAh / g) X trigger voltage (V)) / 1000] / (Cell weight (kg))} Petition 870250085671, dated 09 / 22 / 2025, pages 86 / 94 35 / 38 Table 1 Sulfur (Se) content (%) in sulfur-carbon composite Current collector thickness (pm) Charge (mAh / cm2) Equation 1 Value Weight ratio (%) of Al foil in battery Energy density (relative value, %) Example Comparative 1 75 20 5.0 42.20 11.38 100.0 Example Comparative 2 75 12 5.0 70.34 7.18 104.8 Example Comparative 3 75 10 5.0 84.40 6.05 106.5 Example 1 75 8 5.0 105.5 4.90 107.8 Example 2 75 6 5.0 140.7 3.72 109.1 Table 2 Sulfur (Se) content (%) in sulfur-carbon composite Current collector thickness (pm) Charge (mAh / cm2) Equation 1 Value Weight ratio (%) of Al foil in battery Energy density (relative value, %) Example Comparative 4 75 20 2.3 42.75 20.86 100.0 Example Comparative 5 75 12 2.3 71.25 13.70 109.5 Example Comparative 6 75 10 2.3 85.51 11.69 112.1 Example 3 75 8 2.3 106.9 9.59 115.0 Example 4 75 6 2.3 142.5 7.37 117.8

[0149] The case in Table 1 is a case of a relatively charged electrode Petition 870250085671, dated 09 / 22 / 2025, pp. 87 / 94 36 / 38 high, in which the amount of electrode charge is 5.0 mAh / cm2 in Comparative Examples 1, 2 and 3 and Examples 1 and 2, and the case in Table 2 is a case of a relatively low charge electrode, in which the amount of electrode charge is 2.3 mAh / cm2 in Comparative Examples 4, 5 and 6 and Examples 3 and 4.

[0150] Referring to Figure 1, it can be confirmed that, in the case of the high-charge electrode (charge quantity 5.0 mAh / cm2) (Comparative Examples 1, 2 and 3 and Examples 1 and 2), the mass ratio of the aluminum thin film is relatively high compared to the case of the low-charge electrode (charge quantity 2.3 mAh / cm2) (Comparative Examples 4, 5 and 6 and Examples 3 and 4). This indicates that the lower the charge quantity, the greater the change in the weight ratio of the current collector. Furthermore, it can be confirmed that, as the thickness of the aluminum thin film decreases, the mass ratio of the aluminum thin film naturally decreases.

[0151] Referring to Figure 2, it can be confirmed that, in the case where the amount of charge is small (the amount of charge 2.3 mAh / cm2) (Comparative Examples 4, 5 and 6 and Examples 3 and 4), the portion of aluminum in the electrode becomes relatively large and, therefore, as the thickness of the thin aluminum film decreases, the slope of the increase in energy density increases sharply compared with the high charge electrode (the amount of charge 5.0 mAh / cm2) (Comparative Examples 1, 2 and 3 and Examples 1 and 2). Evaluation Result

[0152] From the results in Tables 1 and 2 above, it was found that when an electrode using a thin-film aluminum current collector with a thickness of 9 μm or less is used, the energy density of the lithium-sulfur battery can be significantly improved compared to when the thickness is greater than 9 μm. For example, as in Table 1, in the case of the high-charge electrode (charge quantity 5.0 mAh / cm2), it was confirmed that when the current collector Petition 870250085671, dated 09 / 22 / 2025, pages 88 / 94 37 / 38 thin-film aluminum current collector has a thickness of 8 pm in Example 2, the energy density was increased by about 10% (to be precise, about 9.1%) compared to when the thin-film aluminum current collector has a thickness of 20 pm in Comparative Example 1. Meanwhile, it can be verified that the values ​​of Equation 1 in Examples 1 and 2 are 105.5 cm² / mAh and 140.7 cm² / mAh, respectively, and are equal to or greater than 90 cm² / mAh.

[0153] Meanwhile, as in Table 2, in the case of the electrode with a low charge quantity (charge quantity 2.3 mAh / cm2), when the aluminum thin-film current collector has a thickness of 6 pm in Example 4, the relative value of the energy density was increased by about 17.8% compared to when the aluminum thin-film current collector has a thickness of 20 pm in Comparative Example 4. It was confirmed that the increase in energy density almost doubled compared to the electrode with a relatively high charge quantity. Meanwhile, it can be verified that the values ​​of Equation 1 in Examples 3 and 4 are 106.9 cm2 / mAh and 142.5 cm2 / mAh, respectively, and are equal to or greater than 90 cm2 / mAh.

[0154] Meanwhile, in the Comparative Examples and Examples above, when a thin aluminum film was used as a current collector, the parameter of about 9 μm or less was calculated based on its thickness, but without limitation. In the present disclosure, for example, parameters can also be calculated based on the types of current collector metals used and the weights and densities of those metals. For example, when Al, Ni, Cu, or Sus is used as a current collector, a condition in which the weight value (mg / cm2) per unit area of ​​the corresponding metal is equal to or less than a specific value can be selected based on the density (d)(g / cm3) and the weight value of the metal. For example, according to one embodiment, when the weight value per unit area (mg / cm2) of the current collector is equal to or less than "0.9 xd", the density Petition 870250085671, dated 09 / 22 / 2025, pages 89 / 94 The energy efficiency of a 38 / 38 sulfur battery can be improved, for example, when the thickness of the aluminum thin-film current collector is 9 μm or less. In this case, the densities of Al, Ni, Cu, and Sus are 2.7 g / cm3, 8.91 g / cm3, 8.96 g / cm3, and 7.93 g / cm3, respectively. Therefore, in a case where the relational expression of "0.9 xd" is applied, a condition corresponding to the condition described above that the thickness of the aluminum thin-film current collector is 9 μm or less is achieved when the weight per unit area of ​​the current collector is 2.43 mg / cm2 or less in an Al current collector, when the weight per unit area of ​​the current collector is 8.019 mg / cm2 or less in a Ni current collector, when the weight per unit area of ​​the current collector is 8.064 mg / cm2 or less in a Cu current collector, and when the weight per unit area of ​​the current collector is 7.137 mg / cm2 or less in a Sus current collector.

[0155] Although descriptions have been made with reference to embodiments of the present disclosure, a person skilled in the relevant technical field or a person of common ability in the relevant technical field would understand that various modifications and changes may be made to the present disclosure within a scope that does not depart from the spirit and technical field of the present disclosure described in the patent claims to be described later. Therefore, the technical scope of the present disclosure is not limited to the content described in the detailed description of the descriptive report, but must be determined by the patent claims. Petition 870250085671, dated 09 / 22 / 2025, pp. 90 / 94

Claims

1 / 3 CLAIMS 1. Electrode, CHARACTERIZED in that it comprises: a current collector; and an electrode active material layer located on at least one side of the current collector, wherein the electrode active material layer includes a sulfur-carbon composite and a binder, the sulfur-carbon composite includes a porous carbon material and a sulfur-based material, and the current collector includes aluminum (Al) and has a thickness of about 9 μm or less.

2. Electrode, according to claim 1, CHARACTERIZED in that a value based on the following Equation 1 satisfies approximately 90 cm² / mAh or more: [Equation 1] (electrode weight — current collector weight) 1 current collector weight amount of electrode charge where: a unit of electrode weight and a unit of current collector weight are grams (g), and an amount of electrode charge is a large amount of sulfur in the electrode, and its unit is mAh / cm² 3. Electrode, according to claim 2, CHARACTERIZED in that the value based on Equation 1 satisfies approximately 100 cm² / mAh to 150 cm² / mAh.

4. Electrode, according to claim 1, CHARACTERIZED in that the thickness of the current collector is about 5 μm to 9 μm. Petition 870250085671, dated 09 / 22 / 2025, pp. 91 / 94 2 / 3 5. Electrode, according to claim 1, CHARACTERIZED in that the content of the sulfur-based material in the active material layer of the electrode is about 65% by weight or more.

6. Electrode, according to claim 1, CHARACTERIZED in that the amount of sulfur charge is about 5 mAh / cm2 or less.

7. Electrode, according to claim 1, CHARACTERIZED in that the amount of sulfur charge is about 3.5 mAh / cm2 or less.

8. Electrode, according to claim 1, CHARACTERIZED in that the current collector is made only of aluminum (Al).

9. Electrode, according to claim 1, CHARACTERIZED in that the current collector includes stainless steel, nickel, titanium, calcined carbon, silver, or two or more types of these components, together with aluminum.

10. Electrode, according to claim 1, CHARACTERIZED in that the current collector has any of the forms of a film, a plate, a sheet, a network, a porous body, a foam, and a non-woven fabric.

11. Electrode, CHARACTERIZED in that it comprises: a current collector; and a layer of electrode active material located on at least one side of the current collector, wherein the layer of electrode active material includes a sulfur-carbon composite and a binder, the sulfur-carbon composite includes a porous carbon material and a sulfur-based material, and the current collector includes a specific metal and a weight value per unit area (mg / cm2) of the specific metal satisfies a value of “0.9 x density (d)” or less. Petition 870250085671, dated 22 / 09 / 2025, pp. 92 / 94 3 / 3 12. Electrode, according to claim 11, CHARACTERIZED in that the specific metal includes any one of aluminum (Al), nickel (Ni), copper (Cu) and stainless steel (Sus).

13. Electrode, according to claim 11, CHARACTERIZED in that the current collector has any of the forms of a film, a plate, a sheet, a network, a porous body, a foam, and a non-woven fabric.

14. Lithium-sulfur battery, CHARACTERIZED in that it comprises: a positive electrode, a negative electrode, a separator interposed between the positive and negative electrodes, and an electrolyte, wherein at least one of the positive and negative electrodes includes a current collector and an active electrode material layer located on at least one side of the current collector, the active electrode material layer includes a sulfur and carbon composite and a binder, the sulfur and carbon composite includes a porous carbon material and a sulfur-based material, and the current collector includes aluminum (Al) and has a thickness of about 9 μm or less.

15. Lithium-sulfur battery, according to claim 14, CHARACTERIZED in that the weight ratio (El / S) of the electrolyte to sulfur is about 3.5 g / g or less.

16. Lithium-sulfur battery, according to claim 14, CHARACTERIZED in that the energy density of the lithium-sulfur battery is about 350 Wh / kg or more. Petition 870250085671, dated 09 / 22 / 2025, pp. 93 / 94

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