TY - JOUR
T1 - Simulation of bi-layer cathode materials with experimentally validated parameters to improve ion diffusion and discharge capacity
AU - Chowdhury, Ridwanur
AU - Banerjee, Aayan
AU - Zhao, Yan
AU - Liu, Xinhua
AU - Brandon, Nigel
N1 - RSC deal
Funding Information:
The authors thank Dr Yuhua Xia for EIS tests and Dr Mengz-heng Ouyang for FIB imaging. The authors also thank Dr Catalina Pino-Muñoz and Dr Antonio Bertei for the insightful discussions. This work is supported by the U.S. Department of Education and the EPSRC project EP/M009521/1 “Enabling next generation lithium batteries”.
Publisher Copyright:
© The Royal Society of Chemistry 2021.
PY - 2021/1/25
Y1 - 2021/1/25
N2 - The prospect of thick graded electrodes for both higher energy and higher-power densities in lithium-ion batteries is investigated. The simulation results discussed in previous reports on next-generation graded electrodes do not recognize the effect of material processing conditions on microstructural, transport and kinetic parameters. Hence, in this work, we focus on the effect of material processing conditions on particle morphology and its subsequent influence on microstructure (porosity and tortuosity), along with the resultant transport (solid-phase diffusivity) and kinetic (reaction rate constant) properties of synthesized single-layer cathodes. These experimental insights are employed to simulate the benefits of 400 μm thick bi-layer graded cathodes with two different particle sizes and porosities in each layer. The microstructural, transport, and kinetic information are obtained through 3D imaging and electrochemical impedance spectroscopy (EIS) techniques. These parameters are used to develop bi-layer numerical models to understand transport phenomena and to predict cell performance with such graded structures. Simulation results highlight that bi-layer cathodes display higher electrode utilization (solid phase lithiation) next to the current-collector compared to conventional monolayer cathodes with an increase of 39.2% in first discharge capacity at 2C. Additionally, the simulations indicate that an improvement of 47.7% in energy density, alongside a marginal increase of 0.6% in power density, can be achieved at 4C by structuring the porosity in the layer next to the separator to be higher than the porosity in the layer next to the current-collector.
AB - The prospect of thick graded electrodes for both higher energy and higher-power densities in lithium-ion batteries is investigated. The simulation results discussed in previous reports on next-generation graded electrodes do not recognize the effect of material processing conditions on microstructural, transport and kinetic parameters. Hence, in this work, we focus on the effect of material processing conditions on particle morphology and its subsequent influence on microstructure (porosity and tortuosity), along with the resultant transport (solid-phase diffusivity) and kinetic (reaction rate constant) properties of synthesized single-layer cathodes. These experimental insights are employed to simulate the benefits of 400 μm thick bi-layer graded cathodes with two different particle sizes and porosities in each layer. The microstructural, transport, and kinetic information are obtained through 3D imaging and electrochemical impedance spectroscopy (EIS) techniques. These parameters are used to develop bi-layer numerical models to understand transport phenomena and to predict cell performance with such graded structures. Simulation results highlight that bi-layer cathodes display higher electrode utilization (solid phase lithiation) next to the current-collector compared to conventional monolayer cathodes with an increase of 39.2% in first discharge capacity at 2C. Additionally, the simulations indicate that an improvement of 47.7% in energy density, alongside a marginal increase of 0.6% in power density, can be achieved at 4C by structuring the porosity in the layer next to the separator to be higher than the porosity in the layer next to the current-collector.
KW - UT-Hybrid-D
UR - https://pubs.rsc.org/no/content/articlehtml/2021/se/d0se01611j#fn1
UR - http://www.scopus.com/inward/record.url?scp=85101494449&partnerID=8YFLogxK
U2 - 10.1039/d0se01611j
DO - 10.1039/d0se01611j
M3 - Article
SN - 2398-4902
VL - 5
SP - 1103
EP - 1119
JO - Sustainable Energy & Fuels
JF - Sustainable Energy & Fuels
IS - 4
ER -