Close this search box.

The Use of Elevated Temperature Storage Experiments to Learn about Parasitic Reactions in Wound LiCoO2∕Graphite Cells

The Use of Elevated Temperature Storage Experiments to Learn about Parasitic Reactions in Wound LiCoO2 ∕ Graphite Cells

Sinha, N. N., Smith, A. J., Burns, J. C., Jain, G., Eberman, K. W., Scott, E., Gardner, J. P., & Dahn, J. R. (2011)
Journal of The Electrochemical Society, 158(11), A1194.



Twenty seven LiCoO2/graphite wound prismatic cells containing a variety of electrolyte additives as well as high or low surface area LiCoO2 were studied during high temperature storage using an automated storage system. The same cells had been previously studied using high precision coulometry. Cells were initially cycled to measure the capacity, charged and then stored for one month at either 40 or 60 °C, then cycled again to measure the reversible and irreversible capacity loss. The process was then repeated. During storage, the open circuit potential was automatically measured every 6 hours. The mechanisms responsible for the voltage drop which occurred during storage and the capacity loss after storage were analysed using a Li inventory model. The voltage drop during storage is caused primarily by parasitic reactions (electrolyte oxidation, transition metal dissolution, etc.) that insert Li into the positive electrode, because the potential of the LixC6 electrode is virtually constant on the stage-2/stage-1 plateau even if its Li content changes due to solid electrolyte interface (SEI) growth. The experimental results show that the combination of the electrolyte additive, vinylene carbonate, and low surface area LiCoO2 minimizes the voltage drop and capacity loss during storage presumably by reducing the amount of electrolyte oxidation occurring at the positive electrode. The same cells had charge endpoint capacity slippages that were closest to 0.00%/cycle during cycling tests monitored with high precision coulometry. Storage experiments, in concert with precision coulometry, allow a clear picture of the effect of additives to be determined.




Resource Category Tags

Resource Format

Related Resources

NOVONIX – Performing DCIR Measurements with a NOVONIX UHPC System

The method presented here leverages user defined variables to perform internal resistance measurements on a NOVONIX UHPC system.

UHPC Protocol – Getting started with custom variables and expressions

As of v2.6.0, UHPC Protocol supports creating and updating variables or math expressions to trigger conditions within the 'Step Control Conditions' and 'Current' text boxes. This document outlines how to get started implementing these custom conditions in your test protocols.

NOVONIX – Screening Graphite Materials for Lifetime Based on UHPC Measurements of Parasitic Current in Half Cells

The method presented here is designed to allow a quantitative ranking among different materials to be made from tests on coin half cells, that can be translated to form a qualitative lifetime prediction in full cells.