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EP-4738445-A1 - ALL-SOLID-STATE BATTERY AND METHOD OF FABRICATING THE SAME

EP4738445A1EP 4738445 A1EP4738445 A1EP 4738445A1EP-4738445-A1

Abstract

Disclosed are all-solid-state batteries and their fabrication methods. The mehtod of fabricating an all-solid-state battery comprises preparing a first substrate and a second substrate, preparing a first electrode plate by forming a first mixture layer on the first substrate, preparing a second electrode plate by forming a second mixture layer on the second substrate, forming a first electrode by transferring the second mixture layer of the second electrode plate to the first mixture layer of the first electrode plate, and performing a post-pressurization step to pressurize the first electrode. The forming of the first electrode comprises performing a pre-pressurization step in which the first electrode plate and the second electrode plate are pressurized while facing each other. The post-pressurization step further comprises cooling the second electrode plate.

Inventors

  • LEE, WONGI
  • CHOI, JINKYU

Assignees

  • SAMSUNG SDI CO., LTD.

Dates

Publication Date
20260506
Application Date
20251031

Claims (15)

  1. A method of fabricating an all-solid-state battery (1000), the method comprising: (S11) preparing a first substrate (PRL1) and a second substrate (PRL2); (S12) preparing a first electrode plate (1) by forming a first mixture layer (121) on the first substrate (PRL1); (S13) preparing a second electrode plate (2) by forming a second mixture layer (122) on the second substrate (PRL2); (S14) forming a first electrode (10) by transferring the second mixture layer (122) of the second electrode plate (2) to the first mixture layer (121) of the first electrode plate (1); and (S15) performing a post-pressurization step to pressurize the first electrode (10), wherein forming the first electrode (10) comprises performing a pre-pressurization step in which the first electrode plate (1) and the second electrode plate (2) are pressurized while facing each other, and wherein the post-pressurization step further comprises cooling the second electrode plate (2).
  2. The method of claim 1, wherein forming the first mixture layer (121) comprises coating a first positive electrode slurry on the first substrate (PRL1), and forming the second mixture layer (122) comprises coating a second positive electrode slurry on the second substrate (PRL2).
  3. The method of any of claims 1 to 2, wherein before transferring the second mixture layer (122) to the first mixture layer (121), the method further comprises: (S121) performing a primary pressurization step to pressurize the first electrode plate (1); and (S131) performing a primary pressurization step to pressurize the second electrode plate (2).
  4. The method of claim 3, wherein the primary pressurization step of the first electrode plate (1) is performed such that the first electrode plate (1) is pressurized at 0.1 tons/cm to 0.3 tons/cm, and the primary pressurization step of the second electrode plate (2) is performed such that the second electrode plate (2) is pressurized at 0.1 tons/cm to 0.3 tons/cm.
  5. The method of any of claims 1 to 4, further comprising removing the second substrate (PRL2) that is cooled after the post-pressurization step.
  6. The method of any of claims 1 to 5, wherein the first substrate (PRL1) and the second substrate (PRL2) comprise aluminum.
  7. The method of any of claims 1 to 6, wherein the post-pressurization step comprises pressurizing the first electrode (10) at 2.0 tons/cm to 2.5 tons/cm.
  8. The method of any of claims 1 to 7, wherein the pre-pressurization step comprises arranging the first electrode plate (1) and the second electrode plate (2) to face each other and pressurizing the first electrode plate (1) and the second electrode plate (2) at 0.3 tons/cm to 0.5 tons/cm.
  9. The method of any of claims 1 to 8, wherein the first mixture layer (121) comprises a first solid electrolyte, the second mixture layer (122) comprises a second solid electrolyte, a weight ratio of the first solid electrolyte in the first mixture layer (121) is 10 wt% to 18 wt% with respect to the first mixture layer (121), and a weight ratio of the second solid electrolyte in the second mixture layer (122) is 20 wt% to 40 wt% with respect to the second mixture layer (122).
  10. The method of any of claims 1 to 9, wherein cooling the second electrode plate (2) is performed by using liquid nitrogen.
  11. An all-solid-state battery (1000), the all-solid-state battery (1000) preferably being produced by a method according to any of the previous claims, the all-solid-state battery (1000) comprising: a positive electrode (100), the positive electrode comprising a positive electrode current collector (110), a first mixture layer (121) on the positive electrode current collector (110), and a second mixture layer (122) on the first mixture layer (121); a solid electrolyte layer (300) on the second mixture layer (122); and a negative electrode layer (200) on the solid electrolyte layer (300), wherein the first mixture layer (121) comprises a first positive electrode active material and a first solid electrolyte, wherein the second mixture layer (122) comprises a second positive electrode active material and a second solid electrolyte, and wherein a weight ratio of the first solid electrolyte in the first mixture layer (121) is less than a weight ratio of the second solid electrolyte in the second mixture layer (122).
  12. The all-solid-state battery (1000) of claim 11, wherein the weight ratio of the first solid electrolyte in the first mixture layer (121) is 10 wt% to 18 wt% with respect to the first mixture layer (121), and the weight ratio of the second solid electrolyte in the second mixture layer (122) is 20 wt% to 40 wt% with respect to the second mixture layer (122).
  13. The all-solid-state battery (1000) of any of claims 11 or 12, further comprising a coating layer between the first mixture layer (121) and the second mixture layer (122), the coating layer comprising carbon.
  14. The all-solid-state battery of claim 13, wherein a thickness of the coating layer is not more than 3 µm.
  15. The all-solid-state battery of any of claims 11 to 14, wherein a loading level on one side of a mixture layer (120) comprising the first mixture layer (121) and the second mixture layer (122) is 30 mg/cm 2 to 35 mg/cm 2 .

Description

CROSS-REFERENCE TO RELATED APPLICATION This application claims priority to Korean Patent Application No. 10-2024-0154347 filed on November 4, 2024 in the Korean Intellectual Property Office. BACKGROUND The present disclosure relates to an all-solid-state battery and a method of fabricating the same. Recently, with the rapid spread of battery using electronic devices, such as mobile phones, laptop computers, and electric vehicles, there is a rapidly increasing demand for rechargeable batteries with high energy density and high capacity. Therefore, intensive research has been conducted to improve performance of rechargeable lithium batteries. A rechargeable lithium battery includes a positive electrode, a negative electrode, and an electrolyte, which positive and negative electrodes include an active material in which intercalation and deintercalation are possible, and generates electrical energy caused by oxidation and reduction reactions when lithium ions are intercalated and deintercalated. Among rechargeable lithium batteries, an all-solid-state battery refers to a battery in which all materials are solid, and particularly, a battery using a solid electrolyte. Such all-solid-state battery exhibits excellent safety due to no risk of electrolyte leakage, and thin-layered battery is readily fabricated. Various methods to increase a capacity of the all-solid-state battery are being studied, and one approach to increasing capacity within a limited volume is to manufacture an electrode plate with high current density. SUMMARY An embodiment of the present disclosure provides an all-solid-state battery with high current density and a method of fabricating the same. An embodiment of the present disclosure provides an all-solid-state battery with a large coating amount of an active material layer and a method of fabricating the same. According to an embodiment of the present disclosure, a method of fabricating an all-solid-state battery may comprise: preparing a first substrate and a second substrate; preparing a first electrode plate by forming a first mixture layer on the first substrate; preparing a second electrode plate by forming a second mixture layer on the second substrate; forming a first electrode by transferring the second mixture layer of the second electrode plate to the first mixture layer of the first electrode plate; and performing a post-pressurization step to pressurize the first electrode. The forming of the first electrode may comprise performing a pre-pressurization step in which the first electrode plate and the second electrode plate are pressurized while facing each other. The post-pressurization step may further comprise cooling the second electrode plate. According to an embodiment of the present disclosure, an all-solid-state battery may comprise: a positive electrode, the positive electrode comprising a positive electrode current collector, a first mixture layer on the positive electrode current collector, and a second mixture layer on the first mixture layer; a solid electrolyte layer on the second mixture layer; and a negative electrode layer on the solid electrolyte layer. The first mixture layer may comprise a first positive electrode active material and a first solid electrolyte. The second mixture layer may comprise a second positive electrode active material and a second solid electrolyte. A weight ratio of the first solid electrolyte in the first mixture layer may be less than a weight ratio of the second solid electrolyte in the second mixture layer. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 illustrates a cross-sectional view showing an all-solid-state battery according to an embodiment of the present disclosure.FIGS. 2A and 2B illustrate flow charts showing a method of fabricating an all-solid-state battery according to an embodiment of the present disclosure.FIGS. 3 to 7 illustrate cross-sectional views showing a method of fabricating an all-solid-state battery according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF EMBODIMENTS In order to sufficiently understand the configuration and effect of the present disclosure, some embodiments of the present disclosure will be described with reference to the accompanying drawings. It should be noted, however, that the present disclosure is not limited to the following exemplary embodiments, and may be implemented in various forms. Rather, the exemplary embodiments are provided only to disclose the present disclosure and let those skilled in the art fully know the scope of the present disclosure. In this description, it will be understood that, when an element is referred to as being on another element, the element can be directly on the other element or intervening elements may be present between therebetween. In the drawings, thicknesses of some components are exaggerated for effectively explaining the technical contents. Like reference numerals refer to like elements throughout the specification. Unless otherwise sp