상세정보
학술지
Graphite-Silicon Diffusion-Dependent Electrode with Short Effective Diffusion Length for High-Performance All-Solid-State Batteries
- 발행일
- 202201
- 출처
- Advanced Energy Materials, v.12 no.3, pp.1-9
- ISSN
- 1614-6832
- 출판사
- Wiley
- 협약과제
- 21JB3100, 나노입자의 차원 제어를 통한 흑연/고체전해질 복합체 기반의 3차원 구조 음극 설계 및 조성 최적화, 이영기
- 초록
- Electrode design, which is closely related to electronic and ionic transport, is an essential factor that influences the performance of all-solid-state batteries. An in-depth understanding of the movement of the charge carriers and its relationship to the electrode structure are urgently needed for the realization of advanced energy storage devices. Herein, a simple electrode configuration, which consists mostly of blended active materials of graphite and silicon, is presented to simultaneously satisfy the high power and high energy density of all-solid-state batteries. This electrode efficiently utilizes interdiffusion between the active material particles for charge/discharge. Mechanically compliant graphite accommodates the volume change of silicon and continuously provides abundant electrons to silicon, which enables a stable electrochemical reaction. Silicon with its higher volumetric capacity compared to graphite, shortens the effective diffusion pathway in the electrode. In particular, the use of the nanometer-scale silicon leads to its uniform distribution throughout the electrode, which increases the contact area capable of interdiffusion between the graphite and silicon and reduces the diffusion in the agglomerated silicon with relatively low diffusivity. This morphology-induced electrochemical change dramatically increases the achievable capacities at higher current densities (93.8% capacity retention (2.76 mAh cm?닋2) at 0.5 C-rate (1.77혻mA cm?닋2) relative to the capacity at 0.1 C-rate).
- KSP 제안 키워드
- Active materials, Charge carriers, Contact area, Diffusion pathway, Effective diffusion length, Electrode structure, High energy density, High performance, High power, Ionic Transport, Nanometer-scale