Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5149332 | Journal of Power Sources | 2017 | 7 Pages |
Abstract
Aqueous processing of thick electrodes for Li-ion cells promises to increase energy density due to increased volume fraction of active materials, and to reduce cost due to the elimination of the toxic solvents. This work reports the processing and characterization of aqueous processed electrodes with high areal loading and associated full pouch cell performance. Cracking of the electrode coatings becomes a critical issue for aqueous processing of the positive electrode as areal loading increases above 20-25Â mg/cm2 (â¼4Â mAh/cm2). Crack initiation and propagation, which was observed during drying via optical microscopy, is related to the build-up of capillary pressure during the drying process. The surface tension of water was reduced by the addition of isopropyl alcohol (IPA), which led to improved wettability and decreased capillary pressure during drying. The critical thickness (areal loading) without cracking increased gradually with increasing IPA content. The electrochemical performance was evaluated in pouch cells. Electrodes processed with water/IPA (80/20Â wt%) mixture exhibited good structural integrity with good rate performance and cycling performance.
Related Topics
Physical Sciences and Engineering
Chemistry
Electrochemistry
Authors
Zhijia Du, K.M. Rollag, J. Li, S.J. An, M. Wood, Y. Sheng, P.P. Mukherjee, C. Daniel, D.L. III,