KR-20260066982-A - GEL POLYMER ELECTROLYTE, LITHIUM METAL BATTERY INCLUDING THE SAME AND METHOD OF MANUFACTURING THEREOF

Abstract

A lithium salt; an organic solvent comprising a first compound represented by the following chemical formula 1 and a second compound which is a fluorine-substituted cyclic carbonate-based compound; and a crosslinked polymer having two or more functional groups, wherein the weight ratio of the first compound to the second compound is 20:1 to 1:5, a gel-type polymer electrolyte, a lithium metal battery comprising the same, and a method for manufacturing the same are presented (Chemical formula 1 is as described in the specification).

Inventors

• 표수진
• 홍동기
• 문종석
• 이강희
• 배우진
• 곽병도
• 신주훈
• 우현식
• 박종석
• 김희민

Assignees

• 삼성에스디아이 주식회사

Dates

Publication Date

20260512

Application Date

20241105

Claims (20)

1. Lithium salt; An organic solvent comprising a first compound represented by the following chemical formula 1 and a second compound which is a fluorine-substituted cyclic carbonate-based compound; and A cross-linked polymer having two or more functional groups, comprising A gel-type polymer electrolyte in which the weight ratio of the first compound and the second compound is 20:1 to 1:5: [Chemical Formula 1] In the above chemical formula 1, L1 is a single-bonded, substituted, or unsubstituted C1 to C10 alkylene group, and R1 is a substituted or unsubstituted C1 to C10 alkyl group, and X1 , X2 , and X3 are each one of the same or different halogen elements.
2. In paragraph 1, A gel-type polymer electrolyte in which X1 to X3 in Chemical Formula 1 above are fluorine elements (F).
3. In paragraph 1, The above chemical formula 1 is a gel-type polymer electrolyte represented by the following chemical formula 1-1: [Chemical Formula 1-1] In the above chemical formula 1-1, R1 is a substituted or unsubstituted C1 to C10 alkyl group.
4. In paragraph 1, The above chemical formula 1 is a gel-type polymer electrolyte represented by the following chemical formula 1-2: [Chemical Formula 1-2] In the above chemical formula 1-2, L1 is a single bond or a substituted or unsubstituted C1 to C10 alkylene group.
5. In paragraph 1, The above Chemical Formula 1 is a gel-type polymer electrolyte represented by the following Chemical Formula 1-3: [Chemical Formula 1-3] .
6. In paragraph 1, A gel-type polymer electrolyte, wherein the content of the first compound is 10 to 40 parts by weight based on 100 parts by weight of the gel-type polymer electrolyte.
7. In paragraph 1, The second compound is a gel-type polymer electrolyte comprising fluoroethylene carbonate (FEC), difluoroethylene carbonate (DFEC), or a combination thereof.
8. In paragraph 1, A gel-type polymer electrolyte in which the weight ratio of the first compound and the second compound is 3:1 to 1:1.
9. In paragraph 1, The above functional group comprises an ester group, a carbonate group, an acrylate group, a methacrylate group, or a combination thereof, in a gel-type polymer electrolyte.
10. In paragraph 1, The above-mentioned crosslinked polymer is a polymerization product of crosslinkable monomers, and The above-mentioned crosslinkable monomers are trimethylolpropane trimethacrylate (TMPTMA), diethylene glycol diacrylate (DEGDA), diethylene glycol dimethacrylate (DEGDMA), triethylene glycol diacrylate (TEGDA), triethylene glycol dimethacrylate (TEGDMA), tetraethylene glycol diacrylate (TTEGDA), glycidyl methacrylate, polyethylene glycol diacrylate (PEGDA), polyethylene glycol dimethacrylate (PEGDMA), polypropylene glycol diacrylate (PPGDA), dipropylene glycol diacrylate (DPGDA), tripropylene glycol diacrylate (TPGDA), dianol diacrylate (DDA), dianol dimethacrylate (DDMA), ethoxylated trimethylolpropane triacrylate (ETPTA), and acrylates. Acrylate-functionalized ethylene oxide, butanediol dimethacrylate, ethoxylated neopentyl glycol diacrylate (NPEOGDA), propoxylated neopentyl glycol diacrylate (NPEOGDA), trimethylolpropane triacrylate (TMPTA), trimethylolpropane trimethacrylate (TMPTMA), pentaerythritol triacrylate (PETA), ethoxylated propoxylated trimethylolpropane triacrylate (TMPEOTA)/(TMPPOTA), propoxylated glyceryl triacrylate, tris(2-hydroxyethyl) isocyanurate triacrylate (THEICTA), pentaerythritol tetraacrylate (PETTA), dipentaerythritol A gel-type polymer electrolyte comprising pentaacrylate (DPEPA), ditrimethylolpropane tetraacrylate (DTMPTTA); diglycidyl ester, diallyl suberate; acrylamide, divinylbenzene, or a combination thereof.
11. In paragraph 1, A gel-type polymer electrolyte in which the content of the cross-linked polymer is 2 to 10 parts by weight based on 100 parts by weight of the gel-type polymer electrolyte.
12. In paragraph 1, The above organic solvent is a gel-type polymer electrolyte further comprising a third compound which is a chain-type carbonate-based compound.
13. In Paragraph 12, The above-mentioned third compound is a gel-type polymer electrolyte comprising dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), methylpropyl carbonate (MPC), ethylpropyl carbonate (EPC), methyl ethyl carbonate (MEC), or a combination thereof.
14. In paragraph 1, The above lithium salt is a gel-type polymer electrolyte comprising lithium difluoro(oxalate)borate (LiDFOB) and LiBF4 .
15. A positive electrode comprising a positive current collector and a positive active material layer on the positive current collector; A cathode including a cathode current collector; A separator disposed between the anode and the cathode; and A lithium metal battery comprising the gel-type polymer electrolyte of claim 1.
16. In paragraph 15, A lithium metal battery, wherein the above-mentioned cathode further comprises a lithium metal layer disposed between the cathode current collector and the separator.
17. In Paragraph 16, The above lithium metal layer comprises lithium or a lithium alloy, and The above lithium alloy is a lithium metal battery comprising a Li-Al alloy, a Li-Sn alloy, a Li-In alloy, a Li-Ag alloy, a Li-Au alloy, a Li-Zn alloy, a Li-Ge alloy, a Li-Si alloy, or a combination thereof.
18. Forming an electrode assembly by arranging a negative current collector, a separator, and a positive electrode; The above electrode assembly is housed in a battery case, and then a composition for forming a gel-type polymer electrolyte is injected into the battery case; and A method for manufacturing a lithium metal battery comprising curing the above-mentioned composition for forming a gel-type polymer electrolyte to form the gel-type polymer electrolyte of claim 1.
19. In Paragraph 18, The process of curing the above-mentioned composition for forming a gel-type polymer electrolyte to form a gel-type polymer electrolyte includes a curing reaction using heat treatment, and A method for manufacturing a lithium metal battery in which the above heat treatment is performed at 40 to 120 ℃.
20. In Paragraph 18, A method for manufacturing a lithium metal battery, wherein the above-described composition for forming a gel-type polymer electrolyte comprises a crosslinkable monomer, a lithium salt, an organic solvent, and a thermal initiator.

Description

Gel-type polymer electrolyte, lithium metal battery including the same, and method of manufacturing the same The invention relates to a gel-type polymer electrolyte, a lithium metal battery containing the same, and a method for manufacturing the same. Currently commercially available lithium secondary batteries mainly use carbon-based negative electrode active materials such as graphite. Carbon-based negative electrode active materials do not change in volume during charging and discharging, so the stability of lithium secondary batteries is high. The theoretical electric capacity of graphite is small, about 372 mAh/g. Lithium metal can be used as a negative electrode active material. The theoretical electric capacity of lithium metal is approximately 3,860 mAh/g, which is larger than that of graphite. During charging and discharging, dendrites may form on the surface of lithium metal due to side reactions with the electrolyte, and the growth of these dendrites can cause a short circuit between the positive and negative electrodes. Consequently, the lifespan characteristics of lithium metal batteries containing lithium metal may be degraded. To solve the aforementioned problems, methods have been proposed in which a protective film is introduced to minimize contact between lithium and the electrolyte to reduce side reactions, or in which a gel polymer electrolyte is used to minimize the exposure of the electrolyte on the electrode surface and create a uniform flow of lithium ions throughout the electrode to suppress lithium dendrite growth by introducing the liquid electrolyte into the network of the cross-linked polymer. FIG. 1 is a cross-sectional view of a lithium metal battery according to an exemplary embodiment. FIG. 2 is a cross-sectional view of a lithium metal battery according to another exemplary embodiment. FIGS. 3 and 4 are schematic perspective views of a lithium metal battery according to an exemplary embodiment. The present inventive concept described below is subject to various modifications and may have various embodiments, and specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the present inventive concept to specific embodiments and should be understood to include all modifications, equivalents, or substitutions that fall within the scope of the description of the present inventive concept. The terms used below are used merely to describe specific embodiments and are not intended to limit the creative concept. Singular expressions include plural expressions unless the context clearly indicates otherwise. In the following, terms such as “comprising” or “having” are intended to indicate the existence of the features, numbers, steps, actions, components, parts, components, materials, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, components, materials, or combinations thereof. The “/” used below may be interpreted as “and” or “or” depending on the context. In the drawings, thicknesses have been enlarged or reduced to clearly represent various layers and regions. Throughout the specification, the same reference numerals have been used for similar parts. Throughout the specification, when a part such as a layer, film, region, or plate is described as being “on” or “above” another part, this includes not only cases where it is directly above another part but also cases where there is another part in between. Throughout the specification, terms such as “first,” “second,” etc., may be used to describe various components, but the components should not be limited by these terms. In this specification and drawings, components having substantially the same functional configuration are referred to by the same reference numerals to avoid redundant descriptions. In the present disclosure, the “size” of a particle is, for example, the “particle diameter” of the particle. The “particle diameter” of the particle represents the average diameter when the particle is spherical and represents the average major axis length when the particle is non-spherical. The particle diameter of the particle can be measured using a particle size analyzer (PSA). The “particle diameter” of the particle is, for example, the average particle diameter. The average particle diameter is, for example, the median particle diameter (D50). The median particle diameter (D50) is the particle size corresponding to the 50% cumulative volume calculated from the side of the particle having a small particle size in the particle size distribution measured, for example by laser diffraction. In the present disclosure, “metal” includes both metals and metalloids such as silicon and germanium in an elemental or ionic state. In this disclosure, “alloy” means a mixture of two or more metals. In the present disclosure, “anode active