If you dig into the technical details of how lithium ion batteries work, it discusses "intercalation" of the anode and cathode plates, which basically means that they have a nanoscale comb-like structure that allows ions to slide in and out of the plate surface, without causing the plates to be chemically eaten away and damaged with each charge and discharge cycle.
For an example of this comb-like structure, see figure 4 of this research paper:
- Computer Simulation of Cathode Materials for Lithium Ion and Lithium Batteries: A Review, https://onlinelibrary.wiley.com/doi/full/10.1002/eem2.12017
- Energy and Environmental Materials, Volume 1, Issue 3, September 2018, Pages 148-173
- First published: 29 October 2018, https://doi.org/10.1002/eem2.12017
- Wiley Online Library, free access
- Citations: 15
Does curling the plates to fit them inside a cylindrical cell have any negative impact on the performance characteristics of this comb-like structure?
Imagine taking a flat plastic hair comb, heating it to soften the plastic, and then curling the spine. The comb tines are either spread far apart in a useless manner, or the tines are bunched up and overlap in an equally useless manner.
It seems possible to me that physically bending or curling the nanoscale structures of an intercalated plate could have similar negative effects on its performance.
Is there is any measurable loss of performance between the tight inner layers and the more gently curled outer layers of a cylindrical lithium ion battery?
I notice that the inner core of many cylindrical lithium ion cells is hollow. Is this because the loss of performance is so severe that it is not worth the effort to attempt to completely pack the center with extreme curled plates?