Inactive Overhang in Silicon Anodes

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: OBrien, Aidin I., Trask, Stephen E., Salpekar, Devashish, Son, Seoung-Bum, Dunlop, Alison R., Veith, Gabriel M., Lu, Wenquan, Ingram, Brian J., Abraham, Daniel P., Jansen, Andrew N., Rodrigues, Marco-Tulio F.
Formato: Preprint
Publicado: 2024
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866929501143826432
author OBrien, Aidin I.
Trask, Stephen E.
Salpekar, Devashish
Son, Seoung-Bum
Dunlop, Alison R.
Veith, Gabriel M.
Lu, Wenquan
Ingram, Brian J.
Abraham, Daniel P.
Jansen, Andrew N.
Rodrigues, Marco-Tulio F.
author_facet OBrien, Aidin I.
Trask, Stephen E.
Salpekar, Devashish
Son, Seoung-Bum
Dunlop, Alison R.
Veith, Gabriel M.
Lu, Wenquan
Ingram, Brian J.
Abraham, Daniel P.
Jansen, Andrew N.
Rodrigues, Marco-Tulio F.
contents Li-ion batteries contain excess anode area to improve manufacturability and prevent Li plating. These overhang areas in graphite electrodes are active but experience decreased Li+ flux during cycling. Over time, the overhang and the anode portions directly opposite to the cathode can exchange Li+, driven by differences in local electrical potential across the electrode, which artificially inflates or decreases the measured cell capacity. Here, we show that lithiation of the overhang is less likely to happen in silicon anodes paired with layered oxide cathodes. The large voltage hysteresis of silicon creates a lower driving force for Li+ exchange as lithium ions transit into the overhang, rendering this exchange highly inefficient. For crystalline Si particles, Li+ storage at the overhang is prohibitive, because the low potential required for the initial lithiation can act as thermodynamic barrier for this exchange. We use micro-Raman spectroscopy to demonstrate that crystalline Si particles at the overhang are never lithiated even after cell storage at 45 oC for four months. Since the anode overhang can affect the forecasting of cell life, cells using silicon anodes may require different methodologies for life estimation compared to those used for traditional graphite-based Li-ion batteries.
format Preprint
id arxiv_https___arxiv_org_abs_2405_09681
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Inactive Overhang in Silicon Anodes
OBrien, Aidin I.
Trask, Stephen E.
Salpekar, Devashish
Son, Seoung-Bum
Dunlop, Alison R.
Veith, Gabriel M.
Lu, Wenquan
Ingram, Brian J.
Abraham, Daniel P.
Jansen, Andrew N.
Rodrigues, Marco-Tulio F.
Chemical Physics
Li-ion batteries contain excess anode area to improve manufacturability and prevent Li plating. These overhang areas in graphite electrodes are active but experience decreased Li+ flux during cycling. Over time, the overhang and the anode portions directly opposite to the cathode can exchange Li+, driven by differences in local electrical potential across the electrode, which artificially inflates or decreases the measured cell capacity. Here, we show that lithiation of the overhang is less likely to happen in silicon anodes paired with layered oxide cathodes. The large voltage hysteresis of silicon creates a lower driving force for Li+ exchange as lithium ions transit into the overhang, rendering this exchange highly inefficient. For crystalline Si particles, Li+ storage at the overhang is prohibitive, because the low potential required for the initial lithiation can act as thermodynamic barrier for this exchange. We use micro-Raman spectroscopy to demonstrate that crystalline Si particles at the overhang are never lithiated even after cell storage at 45 oC for four months. Since the anode overhang can affect the forecasting of cell life, cells using silicon anodes may require different methodologies for life estimation compared to those used for traditional graphite-based Li-ion batteries.
title Inactive Overhang in Silicon Anodes
topic Chemical Physics
url https://arxiv.org/abs/2405.09681