Access the full text.
Sign up today, get DeepDyve free for 14 days.
Mater
(1971)
Solid-State Electron
F. Jones (1947)
Electric ContactsNature, 160
Electronic resistance in lithium‐ion battery positive electrodes is typically attributed to the bulk resistance of the active material and the network resistance of the carbon additive. Expected overpotentials from these bulk components are minimal relative to that from charge‐transfer resistance. However, literature reports show that cell overpotentials are often much more sensitive to conductive additives than the expected level from bulk or percolating‐network transport. This discrepancy motivated a detailed examination of the contact resistance between the active material and conductive additive. The contact and bulk resistances are simultaneously measured using dense bar samples of lithium‐layered oxides (LixNi1 /3Mn1/3Co1/3O2 and LixNi0.5Mn0.3Co0.2O2) in contact with carbon black. It is found that the contact resistance dominates the overall electronic resistance when the length scale is smaller than millimeters; after correcting for contact effects, bulk conductivity of layered oxides is determined to be orders‐of‐magnitude higher than previously reported. In porous electrodes, it is found from three‐electrode electrochemical impedance spectroscopy that the carbon content most heavily influences the low‐frequency regime (≈0.01 Hz), as opposed to the high frequency (>103 Hz) regime expected from electronic percolating properties. Constriction effects within the layered oxide are identified as the dominant mechanism for contact resistance and its implication is investigated for porous electrodes.
Advanced Energy Materials – Wiley
Published: Aug 1, 2022
Keywords: bulk conductivity; electrochemical impedance spectroscopy; layered oxides; li‐ion batteries; transport
Read and print from thousands of top scholarly journals.
Already have an account? Log in
Bookmark this article. You can see your Bookmarks on your DeepDyve Library.
To save an article, log in first, or sign up for a DeepDyve account if you don’t already have one.
Copy and paste the desired citation format or use the link below to download a file formatted for EndNote
Access the full text.
Sign up today, get DeepDyve free for 14 days.
All DeepDyve websites use cookies to improve your online experience. They were placed on your computer when you launched this website. You can change your cookie settings through your browser.