Influence of electrolyte constitution on metal dissolution and surface free energy correlation
- Title
- Influence of electrolyte constitution on metal dissolution and surface free energy correlation
- Alternative Title
- 금속 용출에 관한 전해액 구성에 대한 영향과 표면자유에너지와의 관계
- Author(s)
- Choi, Sung Mo
- DGIST Authors
- Choi, Sung Mo ; Lee, Ho Chun ; Kim, Jae Hyeon
- Advisor
- Lee, Ho Chun
- Co-Advisor(s)
- Kim, Jae Hyeon
- Issued Date
- 2015
- Awarded Date
- 2015. 2
- Type
- Thesis
- Subject
- 금속용출 ; 표면자유에너지 ; LiMn2O4 ; LiNi0.6Co0.2Mn0.2O2 ; 전해액
- Abstract
- One of promising cathode for lithium ion battery is LiMn2O4 (LMO) due to its low cost and environmental inertness. However, LMO suffers from Mn dissolution followed by cell degradation. Mn-dissolution is heavily affected by electrode surface and electrolyte, so it is electrode/electrolyte interfacial phenomenon. However, more methodical research about the relationship between the electrolyte property and Mn-dissolution has not been carried out so far. This study examine the dependence of the Mn-dissolution on electrolyte constitution at various temperature and its kinetics. The Mn2+ ion concentration in the electrolyte at vari-ous temperature storage was analyzed by using atomic absorption spectroscopy (AAS). It was revealed that increasing EC content, storage duration and elevated temperature acceler-ates Mn-dissolution. It is diffusion controlled through the product layer. When increasing EC content, it diminish the activation energy of dissolution on electrode/electrolyte interface. ⓒ 2015 DGIST
- Table Of Contents
-
Ⅰ. Surface free energy measurement to assess metal dissolution behavior of layered oxide LiNi0.6Co0.2Mn0.2O 2 --
1.1 Introduction 1 --
1.1.1 Overview 1 --
1.1.2 Theory of surface free energy calculation 2 --
1.1.3 Capillary rising method for porous materials 8 --
1.1.4 Examples of surface free energy usages to analyze the Li ion batteries 10 --
1.2 Experimental 11 --
1.2.1 Adsorption method 11 --
1.2.2 Preparation of NCM electrode 14 --
1.2.3 Metal dissolution 15 --
1.3 Results and discussion 16 --
1.3.1 Metal dissolution and SFE of Al coated LiNi0.6Co0.2Mn0.2O2 16 --
1.3.2 Analysis of the morphology of Al coated LiNi0.6Co0.2Mn0.2O2 19 --
1.3.3 Connection between SFE and metal dissolution of Al coated LiNi0.6Co0.2Mn0.2O2 20 --
1.4 Conclusions 24 --
Ⅱ. Influence of the electrolyte constitution on the dissolution kinetics of manganese from LiMn2O4 cathode for lithium ion battery --
2.1 Introduction 25 --
2.2 Experimental 27 --
2.3 Results and discussion 29 --
2.3.1 Effects of EC content, reaction temperature and storage time on Mn dissolution 29 --
2.3.2 Kinetics of Mn dissolution 31 --
2.3.3 Chemical reaction controlled 33 --
2.3.4 Diffusion controlled through the product layer 36 --
2.3.5 Activation energy determination 39 --
2.3.6 Effect of solvation energy and HF 41 --
2.4 Conclusions 44 --
Ⅲ. Analysis of surface free energy in battery electrolytes. --
3.1 Introduction 45 --
3.2 Experimental 46 --
3.3 Results and discussion 48 --
3.3.1 Characterization of reference materials 48 --
3.3.2 The surface free energy calculation of propylene carbonate 51 --
3.4 Conclusions 53
- URI
-
http://dgist.dcollection.net/jsp/common/DcLoOrgPer.jsp?sItemId=000001922848
http://hdl.handle.net/20.500.11750/1402
- Degree
- Master
- Department
- Energy Systems Engineering
- Publisher
- DGIST
- Related Researcher
-
-
Lee, Hochun
- Research Interests Lithium-ion batteries; Novel Materials for rechargeable batteries; Novel energy conversion;storage systems; Electrochemistry; 리튬이차전지; 이차전지용 신규 전극 및 전해액; 신규 에너지변환 및 저장 시스템; 전기화학
-
- Files in This Item:
-
기타 데이터 / 2.03 MB / Adobe PDF
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- Appears in Collections:
- Department of Energy Science and Engineering Theses Master
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