Abstract
Reversible Li-ion intercalation into composite Li-ion battery (LIB) electrodes is often accompanied by significant dimensional electrode changes (deformation) resulting in significant deterioration of the cycling performance. Viscoelastic properties of polymeric binders affected by intercalation-induced deformation of composite LIB electrodes have never been probed in situ on operating electrochemical cells. Here, we introduce a newly developed noninvasive method, namely electrochemical quartz-crystal microbalance with dissipation monitoring (EQCM-D), for in situ monitoring of elastic properties of polymeric binders during charging of LIB electrodes. As such, we find EQCM-D as a uniquely suitable tool to track the binder's structural rigidity/softness in composite Li insertion electrodes in real-time by the characteristic increase/decrease of the dissipation factor during the charging-discharging process. The binders partially swollen in aprotic solutions demonstrate intermediate viscoelastic charge-rate-dependent behavior, revealing rigid/soft behavior at high/low charging rates, respectively. The method can be adjusted for continuous monitoring of elastic properties of the polymeric binders over the entire LIB electrodes cycling life.
Original language | English |
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Pages (from-to) | 12353-12356 |
Number of pages | 4 |
Journal | Angewandte Chemie - International Edition |
Volume | 54 |
Issue number | 42 |
DOIs | |
State | Published - 1 Oct 2015 |
Externally published | Yes |
Keywords
- Li-ion batteries
- deformations
- polymeric binders
- quartz-crystal microbalance
- viscoelasticity