리튬 이온 전지용 망가니즈 기반 전환반응 음극 소재
Conversion-Type Mn-Based Anode Materials for Li-ion Batteries
- 주제(키워드) 리튬이온배터리 , 음극 , 전환반응 음극
- 주제(DDC) 621.042
- 발행기관 아주대학교 일반대학원
- 지도교수 김승주
- 발행년도 2024
- 학위수여년월 2024. 2
- 학위명 석사
- 학과 및 전공 일반대학원 에너지시스템학과
- 실제URI http://www.dcollection.net/handler/ajou/000000033351
- 본문언어 한국어
- 저작권 아주대학교 논문은 저작권에 의해 보호받습니다.
초록/요약
The prevailing electrode materials utilized in contemporary applications predominantly belong to intercalation-type, such as Li(NixCoyMn(1-x-y))O2 (NCM), LiFePO4 (LFP), and graphite. Despite their widespread application driven by high stability, intercalation-type materials encounter limitations in enhancing capacity due to their inherent charge-discharge mechanisms. [1] Consequently, there is a growing interest in conversion-type electrode materials as promising candidates for high-energy- density batteries. The appeal of conversion-type materials stems from their ability to store multiple moles of lithium ions per mole of the compound. This distinctive feature positions conversion-type electrodes as promising choices for next generation batteries. This research conducted a comparative study on Mn(OH)2 and Mn(OH)2/Mn3O4 composite, both classified as conversion-type electrode materials, to explore their potential as anode materials for next-generation batteries. The chemical and structural study via XRD, SEM, and TEM analysis confirmed that these materials formed hexagonal plates morphology, which is highly favorable characteristic for preparing additional composites with carbon materials such as graphene sheets. The lithium storage mechanisms on these materials were explored through ex-situ XRD and XPS analysis. The cascade reaction of lithium species, along with Mn metal formation, enables exceptional electrochemical performance. Mn(OH)2/Mn3O4 composite exhibits an impressive discharge capacity of ~2750 mAh g-1 in the initial cycle, significantly surpassing the theoretical capacities of both Mn(OH)2 and Mn3O4. This remarkable performance, exceeding that of bare hydroxide (~1527 mAh g-1), can be attributed to the presence of a small amount of Mn3O4, which improves reversible capacity and electrochemical reversibility. This study unveils the potential of Mn(OH)2/Mn3O4 composite as a high-performance anode material for next-generation batteries, showcasing the advancements that conversion-type electrode materials can bring new developments in battery technology.
more목차
1. Introduction 1
1.1 Conventional Anode Materials for Li-ion Batteries 1
1.2 Conversion-Type Anode Materials 2
2. Materials and Methods 4
2.1 Materials 4
2.2 Synthesis of Mn(OH)2 4
2.3 Mn(OH)2/Mn3O4 Composite Preparation 5
2.4 Characterization 5
2.5 Electrochemical Measurements 6
3. Results and Discussion 7
3.1 Characterization of Mn(OH)2 7
3.2 Conversion Reaction Mechanism of Mn(OH)2 9
3.3 Electrochemical Performance of Mn(OH)2 13
3.4 Characterization of Mn(OH)2/Mn3O4 composite 15
3.5 Conversion Reaction Mechanism of Mn(OH)2/Mn3O4 Composite 20
3.6 Electrochemical Performance of Mn(OH)2/Mn3O4 Composite 23
4. Conclusion 26
5. References 28
국문 초록 31
