UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

Studies of phase transitions in lithium intercalation batteries by dQ/dV measurements Johnson, Geoffrey William

Abstract

First order phase transitions have been detected electrochemically in intercalation batteries. The quantity dQ/dV peaks when the phase front associated with a first order phase transition moves through an intercalation compound, where V is the cell's voltage and Q is the charge that flows. The divergence of dQ/dV is analogous to the divergence of the compressibility of a gas when a first order phase transition occurs. dQ/dV can be measured by the standard electrochemical technique of linear sweep voltammetry, but resolution and clarity are vastly improved by measuring dQ/dV at constant current, which minimizes the distortions in dQ/dV due to kinetic effects. The phase diagram of the lithium intercalated layer compound has been constructed. Applications of dQ/dV measurements to phase transitions in other intercalation systems and to single phase regions are discussed.

Item Media

Item Citations and Data

Rights

For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.