KR101846553B1 - Anode active material of silicon-carbon composite with core-shell structure, manufacturing method for the same and lithium secondary battery comprising the anode active material - Google Patents

Anode active material of silicon-carbon composite with core-shell structure, manufacturing method for the same and lithium secondary battery comprising the anode active material Download PDF

Info

Publication number
KR101846553B1
KR101846553B1 KR1020110138385A KR20110138385A KR101846553B1 KR 101846553 B1 KR101846553 B1 KR 101846553B1 KR 1020110138385 A KR1020110138385 A KR 1020110138385A KR 20110138385 A KR20110138385 A KR 20110138385A KR 101846553 B1 KR101846553 B1 KR 101846553B1
Authority
KR
South Korea
Prior art keywords
core
active material
present
shell
polymer
Prior art date
Application number
KR1020110138385A
Other languages
Korean (ko)
Other versions
KR20130071071A (en
Inventor
최장욱
황태훈
공병선
Original Assignee
한국과학기술원
주식회사 케이씨씨
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 한국과학기술원, 주식회사 케이씨씨 filed Critical 한국과학기술원
Priority to KR1020110138385A priority Critical patent/KR101846553B1/en
Publication of KR20130071071A publication Critical patent/KR20130071071A/en
Application granted granted Critical
Publication of KR101846553B1 publication Critical patent/KR101846553B1/en

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/38—Selection of substances as active materials, active masses, active liquids of elements or alloys
    • H01M4/386—Silicon or alloys based on silicon
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
    • C23C18/02—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition
    • C23C18/12—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition characterised by the deposition of inorganic material other than metallic material
    • C23C18/1204—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition characterised by the deposition of inorganic material other than metallic material inorganic material, e.g. non-oxide and non-metallic such as sulfides, nitrides based compounds
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
    • C23C18/02—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition
    • C23C18/12—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition characterised by the deposition of inorganic material other than metallic material
    • C23C18/125—Process of deposition of the inorganic material
    • C23C18/1254—Sol or sol-gel processing
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
    • C23C18/02—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition
    • C23C18/12—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition characterised by the deposition of inorganic material other than metallic material
    • C23C18/125—Process of deposition of the inorganic material
    • C23C18/1295—Process of deposition of the inorganic material with after-treatment of the deposited inorganic material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/362—Composites
    • H01M4/366—Composites as layered products
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
    • H01M4/587—Carbonaceous material, e.g. graphite-intercalation compounds or CFx for inserting or intercalating light metals
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Abstract

코어-쉘 구조의 실리콘-탄소 복합 음극 활물질, 그 제조방법 및 이를 포함하는 리튬이차전지가 제공된다.
본 발명에 따른 코어-쉘 구조의 실리콘-탄소 복합 음극 활물질은 실리콘 나노입자를 포함하는 코어; 및 상기 코어를 감싸는 쉘을 포함하며, 여기에서 상기 쉘은 탄소로 이루어진 것을 특징으로 하며, 본 발명은 실리콘 나노입자가 코어를 이루며, 탄화된 탄소가 상기 코어를 감싸는 쉘을 이루는, 이른바 코어-쉘 구조의 음극 활물질을 제공한다. 특히 본 발명에 따른 음극 활물질 제조방법은 두 개의 노즐을 이용한 전기방사 방식으로 제조되므로, 대량 생산이 가능하다. 아울러, 실리콘의 부피 증가와 반응면적을 상기 탄소쉘이 막아주거나 최소화시켜, 음극의 미분화를 방지할 수 있고, 본 발명에 따른 음극 활물질을 이용하는 리튬이차전지는 개선된 사이클 특성을 갖는다.There is provided a core-shell structure silicon-carbon composite anode active material, a method of manufacturing the same, and a lithium secondary battery comprising the same.
A core-shell structure silicon-carbon composite anode active material according to the present invention includes a core including silicon nanoparticles; And a shell surrounding the core, wherein the shell is made of carbon. The present invention relates to a method of manufacturing a core-shell structure in which silicon nanoparticles form a core, carbonized carbon forms a shell surrounding the core, Lt; / RTI > In particular, the method of manufacturing the anode active material according to the present invention is manufactured by electrospinning using two nozzles, so that mass production is possible. In addition, the increase in volume and the area of reaction of silicon can be prevented or minimized by the carbon shell, and the lithium secondary battery using the negative electrode active material according to the present invention has improved cycle characteristics.

Description

코어-쉘 구조의 실리콘-탄소 복합 음극 활물질, 그 제조방법 및 이를 포함하는 리튬이차전지{Anode active material of silicon-carbon composite with core-shell structure, manufacturing method for the same and lithium secondary battery comprising the anode active material}TECHNICAL FIELD [0001] The present invention relates to a silicon-carbon composite anode active material having a core-shell structure, a method for manufacturing the same, and a lithium secondary battery including the anode- material}

본 발명은 코어-쉘 구조의 실리콘-탄소 복합 음극 활물질, 그 제조방법 및 이를 포함하는 리튬이차전지에 관한 것으로, 보다 상세하게는 전기방사 방식으로 대량 생산이 가능하며, 우수한 사이클 특성을 갖는 코어-쉘 구조의 실리콘-탄소 복합 음극 활물질, 그 제조방법 및 이를 포함하는 리튬이차전지에 관한 것이다.The present invention relates to a silicon-carbon composite anode active material having a core-shell structure, a process for producing the same, and a lithium secondary battery comprising the same. More particularly, the present invention relates to a core- The present invention relates to a silicon-carbon composite anode active material having a shell structure, a method for producing the same, and a lithium secondary battery comprising the same.

양극 및 음극에서 리튬 이온이 인터칼레이션/디인터칼레이션될 때의 화학전위(chemical potential)의 변화에 의하여 전기 에너지를 생성하는 리튬 이차 전지가 있다. 이러한 리튬 이차 전지는 리튬 이온의 가역적인 인터칼레이션/디인터칼레이션이 가능한 물질을 양극과 음극 활물질로 사용하고, 상기 양극과 음극 사이에 유기 전해질 또는 폴리머 전해질을 충전시켜 제조한다.There is a lithium secondary battery which generates electrical energy by a change in the chemical potential when the lithium ions are intercalated / deintercalated in the positive electrode and the negative electrode. Such a lithium secondary battery is manufactured by using a material capable of reversible intercalation / deintercalation of lithium ions as a positive electrode and a negative electrode active material, and filling an organic electrolyte or a polymer electrolyte between the positive electrode and the negative electrode.

리튬 이차 전지의 양극 활물질로는 리튬 복합금속 화합물이 사용되고 있으며, 그 예로 LiCoO2, LiMn2O4, LiNiO2, LiNi1-xCoxO2(0<x<1), LiMnO2 등의 복합금속 산화물들이 연구되고 있다. 리튬 이차 전지의 음극 활물질로는 리튬의 삽입/탈리가 가능한 흑연 등이 대표적으로 적용되어 왔다. 그러나, 이러한 흑연을 이용한 전극은 전하 용량이 365mAh/g (이론값: 372mAh/g)으로 낮기 때문에, 우수한 용량 특성을 나타내는 리튬 이차 전지를 제공하는데 한계가 있었다.As a cathode active material of a lithium secondary battery, a lithium composite metal compound is used. For example, composite metal oxides such as LiCoO2, LiMn2O4, LiNiO2, LiNi1-xCoxO2 (0 <x <1) and LiMnO2 have been studied. As the negative electrode active material of the lithium secondary battery, graphite capable of inserting / removing lithium has been typically used. However, since such a graphite electrode has a low charge capacity of 365 mAh / g (theoretical value: 372 mAh / g), there is a limit in providing a lithium secondary battery exhibiting excellent capacity characteristics.

이에 실리콘(Si), 게르마늄(Ge) 또는 안티몬(Sb)과 같은 무기물계 활물질이 연구되고 있다. 이러한 무기물계 활물질, 특히, 실리콘계 음극 활물질은 매우 큰 리튬 결합량(이론적 최대치: Li4.1Si)을 나타낼 수 있고, 이는 약 4200 mAh/g의 이론적 용량에 상응한다.Accordingly, inorganic active materials such as silicon (Si), germanium (Ge), and antimony (Sb) have been studied. Such a mineral-based active material, in particular, a silicon-based negative electrode active material, can exhibit a very large amount of lithium bonding (theoretical maximum: Li4.1Si), which corresponds to a theoretical capacity of about 4200 mAh / g.

하지만, 상기 실리콘과 같은 무기물계 음극 활물질은 리튬의 삽입/탈리, 즉, 전지의 충방전시 큰 부피 변화를 야기하여 미분화(pulverization)가 나타날 수 있다. 그 결과, 미분화된 입자가 응집되는 현상이 발생하여, 음극활물질이 전류 집전체로부터 전기적으로 탈리될 수 있고, 이는 긴 사이클 하에서 가역 용량의 손실을 가져올 수 있다. 예를 들어, 실리콘계 음극 활물질을 사용한 리튬 이차 전지의 용량은 약 12회의 사이클 후에 흑연을 사용한 전지의 용량과 비슷해질 수 있다. 이 때문에, 이전에 알려진 무기물계 음극 활물질, 예를 들어, 실리콘계 음극 활물질 및 이를 포함하는 리튬 이차 전지는 높은 전하 용량에 따른 장점에도 불구하고 낮은 사이클 수명 특성 및 용량 유지율을 나타내는 단점이 있었다.However, the inorganic anode active material such as silicon may cause pulverization due to insertion / desorption of lithium, that is, a large volume change when charging / discharging the battery. As a result, aggregation of the undifferentiated particles occurs, and the negative electrode active material can be electrically released from the current collector, which may lead to loss of reversible capacity under a long cycle. For example, the capacity of a lithium secondary battery using a silicon-based negative electrode active material may be similar to the capacity of a battery using graphite after about 12 cycles. For this reason, the previously known inorganic anode active material, for example, a silicon anode active material and a lithium secondary battery including the lithium anode active material have disadvantages in that they exhibit a low cycle life characteristic and a capacity retention ratio despite their advantages according to their high charge capacities.

따라서, 본 발명이 해결하고자 하는 과제는 우수한 사이클 특성을 가지며, 대량 생산이 가능한, 리튬이차전지용 음극 활물질을 제조하는 방법과 이에 의하여 제조된 리튬이차전지용 음극 활물질을 제공하는것이다. Accordingly, an object of the present invention is to provide a method for producing a negative electrode active material for a lithium secondary battery having excellent cycle characteristics and mass production, and to provide a negative electrode active material for a lithium secondary battery produced thereby.

본 발명이 해결하고자 하는 또 다른 과제는 신규한 음극 활물질을 사용함으로써 개선된 사이클 특성과 경제성을 갖는 리튬이차전지를 제공하는 것이다.Another object of the present invention is to provide a lithium secondary battery having improved cycle characteristics and economic efficiency by using a novel negative electrode active material.

상기 과제를 해결하기 위하여, 본 발명은 리튬이차전지용 전극 활물질로서,상기 활물질은 실리콘 나노입자를 포함하는 코어; 및 상기 코어를 감싸는 쉘을 포함하며, 여기에서 상기 쉘은 탄소로 이루어진 것을 특징으로 하는 리튬이차전지용 전극 활물질을 제공한다. In order to solve the above problems, the present invention provides an electrode active material for a lithium secondary battery, wherein the active material comprises a core comprising silicon nanoparticles; And a shell surrounding the core, wherein the shell is made of carbon. The present invention also provides an electrode active material for a lithium secondary battery.

본 발명의 일 실시예에서 상기 탄소는 상기 코어를 감싸는 제 1 폴리머를 열처리함으로써 탄화된 물질이며, 상기 폴리머는 제 1 폴리머는 폴리아크릴로니트릴인 것을 특징으로 하는 리튬이차전지용 전극 활물질.In one embodiment of the present invention, the carbon is a material carbonized by heat-treating a first polymer surrounding the core, and the first polymer is polyacrylonitrile.

본 발명의 일 실시예에서상기 리튬이차전지용 전극 활물질은 전기방사 방식으로 제조된다. In an embodiment of the present invention, the electrode active material for a lithium secondary battery is manufactured by electrospinning.

상기 또 다른 과제를 해결하기 위하여 본 발명은 실리콘 나노입자를 함유하는 코어, 및 상기 코어를 감싸는 탄소 쉘로 이루어진 리튬이차전지용 전극 활물질 제조방법으로, 상기 방법은 탄소를 원소로 포함하는 제 1 폴리머와 실리콘 나노입자를 포함하는 제 2 폴리머를 동시에 전기방사시켜, 코어인 제 2 폴리머와 상기 제 2 폴리머의 외측을 감싸는 쉘인 제 1 폴리머를 포함하는 코어-쉘 구조체를 형성시키는 단계; 및 상기 코어-쉘 구조체를 열처리하여 상기 구조체의 쉘을 탄화시키는 단계를 포함하는 것을 특징으로 하는 리튬이차전지용 전극 활물질 제조방법을 제공한다. According to another aspect of the present invention, there is provided a method of manufacturing an electrode active material for a lithium secondary battery, the method comprising: forming a first electrode containing carbon as an element, Forming a core-shell structure comprising electrospinning a second polymer comprising nanoparticles simultaneously to form a core-shell structure comprising a first polymer as a core and a first polymer as a shell surrounding the outside of the second polymer; And subjecting the core-shell structure to a heat treatment to carbonize the shell of the structure. The present invention also provides a method for manufacturing an electrode active material for a lithium secondary battery.

본 발명의 일 실시예에서 상기 전기 방사는 상기 제 2 폴리머를 중심에서 전기방사함과 동시에 상기 제 1 폴리머를 상기 제 2 폴리머의 외측에서 전기방사하는 방식으로 진행되며, 제 1 폴리머는 폴리아크릴로니트릴이며, 상기 제 2 폴리머는 폴리메틸메타크릴레이트이다. In one embodiment of the present invention, the electrospinning is conducted in such a manner that the second polymer is electrospun and the first polymer is electrospun outside of the second polymer, and the first polymer is a polyacrylate Nitrile, and the second polymer is polymethyl methacrylate.

본 발명은 상술한 리튬이차전지용 전극 활물질 제조방법에 사용되는 전기방사 장치로서, 상기 장치는 상기 제 1 폴리머가 전기방사되는 제 1 노즐과 상기 제 2 폴리머가 전기방사되는 제 2 노즐을 포함하는 것을 특징으로 하는 리튬이차전지용 전극 활물질 제조장치를 제공한다. The present invention is an electrospinning apparatus for use in a method for producing an electrode active material for a lithium secondary battery, wherein the apparatus includes a first nozzle through which the first polymer is electrospun and a second nozzle through which the second polymer is electrospun The present invention also provides an apparatus for producing an electrode active material for a lithium secondary battery.

본 발명의 일 실시예에서 상기 제 1 노즐은 원을 이루며, 상기 제 2 노즐은 상기 제 1 노즐의 중심에 위치한다. In one embodiment of the present invention, the first nozzle is a circle, and the second nozzle is located at the center of the first nozzle.

본 발명은 또한 상술한 리튬이차전지용 전극 활물질을 포함하는 것을 특징으로 하는 리튬이차전지를 제공하며, 상기 전극 활물질은 상기 리튬이차전지의 음극에 사용된다.The present invention also provides a lithium secondary battery comprising the above-described electrode active material for a lithium secondary battery, wherein the electrode active material is used for a cathode of the lithium secondary battery.

본 발명은 실리콘 나노입자가 코어를 이루며, 탄화된 탄소가 상기 코어를 감싸는 쉘을 이루는, 이른바 코어-쉘 구조의 음극 활물질을 제공한다. 특히 본 발명에 따른 음극 활물질 제조방법은 두 개의 노즐을 이용한 전기방사 방식으로 제조되므로, 대량 생산이 가능하다. 아울러, 실리콘의 부피 증가와 반응면적을 상기 탄소쉘이 막아주거나 최소화시켜, 음극의 미분화를 방지할 수 있고, 본 발명에 따른 음극 활물질을 이용하는 리튬이차전지는 개선된 사이클 특성을 갖는다.The present invention provides a so-called core-shell structure negative electrode active material in which silicon nanoparticles form a core and carbonized carbon forms a shell surrounding the core. In particular, the method of manufacturing the anode active material according to the present invention is manufactured by electrospinning using two nozzles, so that mass production is possible. In addition, the increase in volume and the area of reaction of silicon can be prevented or minimized by the carbon shell, and the lithium secondary battery using the negative electrode active material according to the present invention has improved cycle characteristics.

도 1은 본 발명의 일 실시예에 따른 전극 활물질의 구조를 설명하는 도면이다.
도 2는 본 발명의 일 실시예에 따른 공정 중 전기방사된 후의 SEM 이미지이고, 도 3은 열처리 공정 후 제조된 전극 활물질의 SEM 이미지이다.
도 4a 내지 4c는 본 발명의 일 실시예에 따른 전극 활물질 제조공정을 설명하는 도면이다.
도 5는 본 발명의 일 실시예에 따른 전기방사 장치의 노즐 구성을 나타낸다.
도 6은 본 발명의 일 실시예에 따른 전기방사장치의 사진이고, 도 7은 실제 전기방사되는 모습의 이미지이다.
도 8 내지 10은 본 발명에 따라 제조된 코어-쉘 구조의 섬유 사진이다.
도 11은 본 발명에 따른 전극 활물질을 리튬이차전지의 음극으로 사용한 경우의 전기화학 분석 결과이다.1 is a view for explaining a structure of an electrode active material according to an embodiment of the present invention.
FIG. 2 is an SEM image after electrospinning in a process according to an embodiment of the present invention, and FIG. 3 is an SEM image of an electrode active material manufactured after a heat treatment process.
4A to 4C are diagrams illustrating a process of manufacturing an electrode active material according to an embodiment of the present invention.
5 shows a nozzle configuration of an electrospinning device according to an embodiment of the present invention.
FIG. 6 is a photograph of an electrospinning device according to an embodiment of the present invention, and FIG. 7 is an image of actually being electrospun.
8 to 10 are photographs of fibers of a core-shell structure made according to the present invention.
11 is an electrochemical analysis result when the electrode active material according to the present invention is used as a negative electrode of a lithium secondary battery.

이하, 본 발명의 도면을 참조하여 상세하게 설명하고자 한다. 다음에 소개되는 실시예들은 당업자에게 본 발명의 사상이 충분히 전달될 수 있도록 하기 위해 예로서 제공되는 것이다. 따라서 본 발명은 이하 설명된 실시예들에 한정되지 않고 다른 형태로 구체화될 수도 있다. 그리고 도면들에 있어서, 구성요소의 폭, 길이, 두께 등은 편의를 위하여 과장되어 표현될 수도 있다. 명세서 전체에 걸쳐서 동일한 참조번호들은 동일한 구성요소들을 나타낸다. 또한, 본 명세서 전반에 걸쳐 표시되는 약어는 본 명세서 내에서 별도의 다른 지칭이 없다면 당업계에서 통용되어, 이해되는 수준으로 해석되어야 한다. Hereinafter, the present invention will be described in detail with reference to the drawings. The following embodiments are provided by way of example so that those skilled in the art can fully understand the spirit of the present invention. Therefore, the present invention is not limited to the embodiments described below, but may be embodied in other forms. In the drawings, the width, length, thickness, etc. of components may be exaggerated for convenience. Like reference numerals designate like elements throughout the specification. In addition, abbreviations displayed throughout this specification should be interpreted to the extent that they are known and used in the art unless otherwise indicated herein.

본 발명은 실리콘 나노입자를 포함하는 코어와 상기 실리콘 나노입자의 코어를 감싸는 형태의 탄소 쉘로 이루어진 코어-쉘 구조이다. 특히, 본 발명에 따른 실리콘 나노입자(코어)-탄소(쉘) 구조는 두 개의 전구체 폴리머를 동시에 전기방사시킨 후, 이를 열처리하는 방식으로 제조된다. 따라서, 대량생산이 가능한 전기방사에 따라 본 발명에 따른 전극 활물질은 대량 생산이 가능하다. The present invention is a core-shell structure comprising a core comprising silicon nanoparticles and a carbon shell in the form of wrapping the core of the silicon nanoparticles. In particular, the silicon nanoparticle (core) -carbon (shell) structure according to the present invention is manufactured by electrospinning two precursor polymers at the same time and then heat-treating them. Therefore, the electrode active material according to the present invention can be mass-produced according to electrospinning capable of mass production.

도 1은 본 발명의 일 실시예에 따른 전극 활물질의 구조를 설명하는 도면이다.1 is a view for explaining a structure of an electrode active material according to an embodiment of the present invention.

도 1을 참조하면, 실리콘 나노입자로 이루어진 코어(110)와 상기 코어를 감싸는 쉘(120)이 개시되며, 상기 코어-쉘 구조는 전기 방사에 따라 제조되므로, 섬유 형태를 이룬다. 상기 쉘은 전기전도도를 갖는 탄소로 이루어지며, 상기 코어의 실리콘 나노입자는 입자 각각이 분산된 형태가 아니라, 서로 응집된 네트워크 구조를 이룬다. 본 발명의 일 실시에에서 상기 쉘 탄소 형성과 코어 입자의 응집, 네트워크 형성은 열처리 공정에 의하여 달성된다.Referring to FIG. 1, a core 110 made of silicon nanoparticles and a shell 120 surrounding the core are disclosed, and the core-shell structure is fabricated according to electrospinning, so that it is in the form of a fiber. The shell is made of carbon having electrical conductivity, and the silicon nanoparticles of the core do not have a dispersed form of each particle but form a network structure that is cohesive with each other. In one embodiment of the present invention, shell carbon formation and aggregation of the core particles, network formation are accomplished by a heat treatment process.

도 2는 본 발명의 일 실시예에 따른 공정 중 전기방사된 후의 SEM 이미지이고, 도 3은 열처리 공정 후 제조된 전극 활물질의 SEM 이미지이다.FIG. 2 is an SEM image after electrospinning in a process according to an embodiment of the present invention, and FIG. 3 is an SEM image of an electrode active material manufactured after a heat treatment process.

도 2 및 3을 참조하면, 전기방사 후 얻어지는 섬유가 최종 열처리 이후에도 동일한 형태를 유지함을 알 수 있다. 특히 최종 산물에는 응집된 형태의 실리콘 나노입자가 코어를 이루는 것을 알 수 있다(도 3의 내삽된 이미지 참조).Referring to Figures 2 and 3, it can be seen that the fibers obtained after electrospinning retain the same shape after the final heat treatment. Especially in the final product, it can be seen that the agglomerated silicon nanoparticles form the core (see the interpolated image of FIG. 3).

도 4a 내지 4c는 본 발명의 일 실시예에 따른 전극 활물질 제조공정을 설명하는 도면이다.4A to 4C are diagrams illustrating a process of manufacturing an electrode active material according to an embodiment of the present invention.

도 4a를 참조하면, 먼저 실리콘 나노입자(210)를 포함하는 코어인 제 2 폴리머(220)와 상기 제 2 폴리머(220)를 감싸는 쉘인 제 1 폴리머(230)로 이루어진 코어-쉘 구조체가 전기방사 방식으로 얻어진다. 상기 전기 방사 방식은 상기 제 2 폴리머(220)를 중심으로 상기 제 1 폴리머(230)를 바깥쪽에서 전기방사하는 방식으로 진행되는데, 이는 이하 상세히 설명된다. 본 발명의 일 실시예에서 제 1 폴리머는 탄화 후 탄소가 남을 수 있는 폴리아크릴로니트릴(PAN)이며, 상기 실리콘 나노입자의 전기방사를 위한 전구체인 제 2 폴리머는 폴리메틸메타크릴레이트(PMMA)이었으나, 본 발명의 범위는 이에 제한되지 않으며, 전기방사에 사용될 수 있는 임의의 모든 폴리머가 본 발명의 범위에 속한다. Referring to FIG. 4A, a core-shell structure including a first polymer 230, which is a core including silicon nanoparticles 210, and a first polymer 230, which is a shell that surrounds the second polymer 220, &Lt; / RTI &gt; The electrospinning process is performed by electrospinning the first polymer 230 from the outside of the second polymer 220, which will be described in detail below. In one embodiment of the present invention, the first polymer is polyacrylonitrile (PAN), which can remain carbon after carbonization, and the second polymer, which is a precursor for electrospinning of the silicon nanoparticles, is polymethylmethacrylate (PMMA) , But the scope of the present invention is not limited thereto and any polymer that can be used for electrospinning is within the scope of the present invention.

도 4b를 참조하면, 상기 전기방사에 의하여 코어-쉘 구조를 얻은 후, 상기 얻은 섬유구조에 대한 열처리가 진행된다. 상기 열처리에 의하여 상기 쉘의 제 1 폴리머는 탄화되어 탄소-쉘이 형성된다. 아울러, 상기 열처리 공정에 의하여 코어의 전구체 폴리머 또한 탄화되거나 열분해되어 제거되는데, 이때 상기 분사된 실리콘 나노입자는 서로 응집되어, 실리콘 나노입자 코어를 이루게 된다(도 4c 참조). Referring to FIG. 4B, after the core-shell structure is obtained by the electrospinning, the obtained fiber structure is subjected to heat treatment. By the heat treatment, the first polymer of the shell is carbonized to form a carbon-shell. In addition, the precursor polymer of the core is also carbonized or thermally decomposed and removed by the heat treatment process, wherein the injected silicon nanoparticles aggregate to form a silicon nanoparticle core (see FIG. 4C).

도 5는 본 발명의 일 실시예에 따른 전기방사 장치의 노즐 구성을 나타낸다. 5 shows a nozzle configuration of an electrospinning device according to an embodiment of the present invention.

도 5를 참조하면, 중심에서 나노입자 함유 제 2 폴리머를 방사하기 위한 제 2 노즐(510)과 상기 제 2 노즐 외측으로 형성된 원형의 제 1 노즐(520)이 개시된다. 즉, 본 발명은 두 개의 노즐로부터 동시에 방사되는 두 종류의 폴리머를 이용, 코어-쉘 구조를 만들고, 다시 이를 열처리하여 실리콘 나노입자(코어)-탄소(쉘)의 복합 재료를 얻는다. Referring to FIG. 5, a second nozzle 510 for emitting a second polymer containing nanoparticles at the center and a circular first nozzle 520 formed outside the second nozzle are disclosed. That is, in the present invention, a core-shell structure is formed using two kinds of polymers simultaneously emitted from two nozzles, and then heat treatment is performed to obtain a composite material of silicon nanoparticles (core) and carbon (shell).

도 6은 본 발명의 일 실시예에 따른 전기방사장치의 사진이고, 도 7은 실제 전기방사되는 모습의 이미지이다.FIG. 6 is a photograph of an electrospinning device according to an embodiment of the present invention, and FIG. 7 is an image of actually being electrospun.

도 7을 참조하면, 코어 노즐(제 2 노즐)의 PMMA와 쉘 노즐(제 1 노즐)의 PAN이 동시에 전기방사되어, 도 8 내지 10에서 도시한 바와 같이 코어-쉘 구조의 섬유가 얻어지는 것을 알 수 있다. 특히, 도 9 내지 10을 참조하면, 내부에 응집된 형태의 실리콘 나노입자가 코어 구조를 이루고 있음을 알 수 있으며, 그 외측으로는 비교적 매끈한 형상의 탄소 쉘이 형성되었음을 알 수 있다. Referring to Fig. 7, it can be seen that the PMMA of the core nozzle (the second nozzle) and the PAN of the shell nozzle (the first nozzle) are simultaneously electrospun to obtain the core-shell structure fibers as shown in Figs. . In particular, referring to FIGS. 9 to 10, it can be seen that the aggregated silicon nanoparticles form a core structure, and a relatively smooth carbon shell is formed on the outer side.

도 11은 본 발명에 따른 전극 활물질을 리튬이차전지의 음극으로 사용한 경우의 전기화학 분석 결과이다.11 is an electrochemical analysis result when the electrode active material according to the present invention is used as a negative electrode of a lithium secondary battery.

도 11을 참조하면, 본 발명에 따른 전극 활물질을 리튬이차전지로 사용하는 경우, 우수한 전기적 특성과 사이클 특성을 관찰할 수 있음을 알 수 있다. Referring to FIG. 11, when the electrode active material according to the present invention is used as a lithium secondary battery, excellent electrical characteristics and cycle characteristics can be observed.

이상 본 발명의 바람직한 실시예를 참조하여 설명하였지만 해당 기술 분야의 숙련된 당업자라면 하기의 특허청구범위에 기재된 본 발명의 사상 및 영역으로부터 벗어나지 않는 범위 내에서 본 발명을 다양하게 수정 및 변경시킬 수 있음을 이해할 수 있을 것이다.While the present invention has been described with reference to exemplary embodiments thereof, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention as defined in the appended claims. .

Claims (11)

삭제delete 삭제delete 삭제delete 삭제delete 실리콘 나노입자를 함유하는 코어, 및 상기 코어를 감싸는 탄소 쉘로 이루어진 리튬이차전지용 전극 활물질 제조방법으로, 상기 방법은
탄소를 원소로 포함하는 제 1 폴리머와 실리콘 나노입자를 포함하는 제 2 폴리머를 동시에 전기방사시켜, 코어인 제 2 폴리머와 상기 제 2 폴리머의 외측을 감싸는 쉘인 제 1 폴리머를 포함하는 코어-쉘 구조체를 형성시키는 단계; 및
상기 코어-쉘 구조체를 열처리하여 상기 구조체의 쉘을 탄화시키는 단계를 포함하는 것을 특징으로 하는 리튬이차전지용 전극 활물질 제조방법.A method for producing an electrode active material for a lithium secondary battery, comprising a core containing silicon nanoparticles and a carbon shell surrounding the core,
A core-shell structure comprising a first polymer comprising carbon as an element and a second polymer comprising silicon nanoparticles simultaneously electrospinning, the first polymer being a shell that surrounds a second polymer as a core and an outer side of the second polymer ; And
And thermally treating the core-shell structure to carbonize the shell of the structure. 제 5항에 있어서,
상기 전기 방사는 상기 제 2 폴리머를 중심에서 전기방사함과 동시에 상기 제 1 폴리머를 상기 제 2 폴리머의 외측에서 전기방사하는 방식으로 진행되는 것을 특징으로 하는 리튬이차전지용 전극 활물질 제조방법.6. The method of claim 5,
Wherein the electrospinning is performed by electrospinning the second polymer at a center and electrospinning the first polymer outside the second polymer. 제 5항에 있어서,
제 1 폴리머는 폴리아크릴로니트릴이며, 상기 제 2 폴리머는 폴리메틸메타크릴레이트인 것을 특징으로 하는 리튬이차전지용 전극 활물질 제조방법.6. The method of claim 5,
Wherein the first polymer is polyacrylonitrile, and the second polymer is polymethyl methacrylate. 삭제delete 삭제delete 삭제delete 삭제delete
KR1020110138385A 2011-12-20 2011-12-20 Anode active material of silicon-carbon composite with core-shell structure, manufacturing method for the same and lithium secondary battery comprising the anode active material KR101846553B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1020110138385A KR101846553B1 (en) 2011-12-20 2011-12-20 Anode active material of silicon-carbon composite with core-shell structure, manufacturing method for the same and lithium secondary battery comprising the anode active material

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR1020110138385A KR101846553B1 (en) 2011-12-20 2011-12-20 Anode active material of silicon-carbon composite with core-shell structure, manufacturing method for the same and lithium secondary battery comprising the anode active material

Publications (2)

Publication Number Publication Date
KR20130071071A KR20130071071A (en) 2013-06-28
KR101846553B1 true KR101846553B1 (en) 2018-04-09

Family

ID=48865673

Family Applications (1)

Application Number Title Priority Date Filing Date
KR1020110138385A KR101846553B1 (en) 2011-12-20 2011-12-20 Anode active material of silicon-carbon composite with core-shell structure, manufacturing method for the same and lithium secondary battery comprising the anode active material

Country Status (1)

Country Link
KR (1) KR101846553B1 (en)

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102013014627A1 (en) * 2013-08-30 2015-03-05 Volkswagen Aktiengesellschaft Pre-lithiation of silicon particles
KR101594836B1 (en) * 2014-04-07 2016-02-26 전남대학교산학협력단 Graphene-metal nano particle complex, carbon nanofiber composites comprising the complex, and rechargeable battery comprising th composites
KR101615439B1 (en) * 2014-07-17 2016-05-13 오씨아이 주식회사 Manufacturing mehtod of carbon-silicon composite
KR101888230B1 (en) 2014-11-27 2018-08-13 주식회사 엘지화학 Silicon-based anode active material and its fabrication method
WO2016085282A1 (en) * 2014-11-27 2016-06-02 주식회사 엘지화학 Silicon-based negative electrode active material and method for manufacturing same
EP3144277A1 (en) 2015-09-17 2017-03-22 Korea Institute of Energy Research Method of carbon coating on nanoparticle and carbon coated nanoparticle produced by the same
CN106571451A (en) * 2016-10-26 2017-04-19 浙江天能能源科技股份有限公司 Lithium ion battery anode material, and preparation method thereof
CN108963229B (en) * 2018-07-23 2021-03-26 中国科学院金属研究所 High-performance silicon negative electrode active material and preparation method thereof
CN112271297B (en) * 2020-10-20 2022-09-06 西安工程大学 Grid type laminated structure material synthesis and molding integrated silicon cathode and preparation method thereof
CN114284479A (en) * 2021-12-22 2022-04-05 博路天成新能源科技有限公司 Preparation method of novel carbon-silicon negative electrode material
CN114843461A (en) * 2022-04-18 2022-08-02 晖阳(贵州)新能源材料有限公司 Preparation method of low-expansion silicon-based composite material
CN115652479A (en) * 2022-10-27 2023-01-31 北京化工大学 Method for preparing silicon carbide hollow microspheres by electrostatic spinning method

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
Angew. Chem. Int. Ed. 2009, 48, pp6485-6489*
Nano Lett., Vol. 8, No. 11, 2008, pp3688-3691*

Also Published As

Publication number Publication date
KR20130071071A (en) 2013-06-28

Similar Documents

Publication Publication Date Title
KR101846553B1 (en) Anode active material of silicon-carbon composite with core-shell structure, manufacturing method for the same and lithium secondary battery comprising the anode active material
KR101875950B1 (en) Manufacturing method for anode active material of lithium secondary battery comprising carbon composite nano particle with silicon porosity, anode active material of lithium secondary battery manufactured by the same, and lithium secondary battery comprising the same
Lu et al. High-performance anode materials for rechargeable lithium-ion batteries
JP6070661B2 (en) Positive electrode mixture, positive electrode, solid state battery, and production method thereof
CN105152166B (en) The manufacture method of graphite material and the manufacture method of electrode for lithium ion secondary battery
Guo et al. Cyclability study of silicon–carbon composite anodes for lithium-ion batteries using electrochemical impedance spectroscopy
JP6141859B2 (en) Lithium secondary battery with improved safety and stability
Ruther et al. Chemical evolution in silicon–graphite composite anodes investigated by vibrational spectroscopy
JP6469576B2 (en) Method of manufacturing electrode material for lithium-ion secondary battery and lithium-ion battery using the electrode material
CN101604745B (en) Silicate positive electrode material for lithium ion power battery, preparation method thereof and lithium ion power battery
CN104919632B (en) Secondary lithium batteries high-capacity electrode active material and use its lithium secondary battery
Gan et al. Enhancing delithiation reversibility of Li15Si4 alloy of silicon nanoparticles-carbon/graphite anode materials for stable-cycling lithium ion batteries by restricting the silicon particle size
Wang et al. Assembly of LiMnPO4 nanoplates into microclusters as a high-performance cathode in lithium-ion batteries
KR20160085386A (en) Anode active material, secondary battery, and manufacturing method of anode active material
KR20090045652A (en) Negative electrode active material, method for manufacturing the same and lithium secondary battery using the negative electrode active material
JP2000164218A (en) Negative electrode active material for lithium secondary battery, and manufacture thereof, and lithium secondary battery including the same
US9368792B2 (en) Negative active material for rechargeable lithium battery, method of preparing the same, and rechargeable lithium battery including the same
Lai et al. Effect of surface modification with spinel NiFe2O4 on enhanced cyclic stability of LiMn2O4 cathode material in lithium ion batteries
CN103608961B (en) Rechargeable nonaqueous electrolytic battery
Gautam et al. Direct-contact prelithiation of Si–C anode study as a function of time, pressure, temperature, and the cell ideal time
Jin et al. Simple approach: Heat treatment to improve the electrochemical performance of commonly used anode electrodes for Lithium-ion batteries
Shi et al. Facile preparation of silicon/carbon composite with porous architecture for advanced lithium-ion battery anode
KR101226107B1 (en) Anode active material for lithium secondary battery And Lithium secondary battery comprising the same
Pan et al. Toward promising turnkey solution for next-generation lithium ion batteries: scale preparation, fading analysis, and enhanced performance of microsized Si/C composites
JP5912534B2 (en) Method for producing non-aqueous electrolyte secondary battery

Legal Events

Date Code Title Description
A201 Request for examination
E902 Notification of reason for refusal
E701 Decision to grant or registration of patent right
GRNT Written decision to grant