Effect of Secondary Heat Treatment after a Washing on the Electrochemical Performance of Co-Free LiNi0.975Al0.025O2 Cathodes for Li-Ion Batteries
Year of publication
2024
Authors
Välikangas, Juho; Laine, Petteri; Hu, Tao; Tynjälä, Pekka; Selent, Marcin; Molaiyan, Palanivel; Jürgen, Kahr; Lassi, Ulla
Abstract
The steadily growing electric vehicle market is a driving force in low-cost, high-energy-density lithium-ion battery development. To meet this demand, LiNi0.975Al0.025O2 (LNA), a high-energy-density and cobalt-free cathode material, has been developed using a low-cost and efficient co-precipitation and lithiation process. This article explores how further processing (i.e., washing residual lithium from the secondary particle surface and applying a secondary heat treatment at 650 °C) changes the chemical environment of the surface and the electrochemical performance of the LNA cathode material. After washing, a nonconductive nickel oxide (NiO) phase is formed on the surface, decreasing the initial capacity in electrochemical tests, and suppressing high-voltage (H2) to (H3) phase transition results in enhanced cycle properties. Furthermore, the secondary heat treatment re-lithiates surface NiO back to LNAand increases the initial capacity with enhanced cycle properties. Electrochemical tests are performed with the cells without tap charge to suppress the H2 to H3 phase transition. Results reveal that avoiding charging cells at a high voltage for a long time dramatically improves LNA's cycle life. In addition, the gas analysis tests performed during charge and discharge to reveal how the amount of residual lithium compounds on the surface affects gas formation are studied.
Show moreOrganizations and authors
Publication type
Publication format
Article
Parent publication type
Journal
Article type
Original article
Audience
ScientificPeer-reviewed
Peer-ReviewedMINEDU's publication type classification code
A1 Journal article (refereed), original researchPublication channel information
Journal
Publisher
Issue
4
Article number
2305349
ISSN
Publication forum
Publication forum level
3
Open access
Open access in the publisher’s service
Yes
Open access of publication channel
Partially open publication channel
License of the publisher’s version
CC BY
Self-archived
Yes
License of the self-archived publication
CC BY
Other information
Fields of science
Chemical sciences
Keywords
[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Publication country
Germany
Internationality of the publisher
International
Language
English
International co-publication
Yes
Co-publication with a company
Yes
DOI
10.1002/smll.202305349
The publication is included in the Ministry of Education and Culture’s Publication data collection
Yes