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Title: Chemo-mechanical degradation in V 2 O 5 thin film cathodes of Li-ion batteries during electrochemical cycling
We have devised an approach to fabricate dense textured V 2 O 5 thin films, which allows us to scrutinize the root cause of capacity fade in V 2 O 5 cathodes of Li-ion batteries. Specifically, we performed in situ measurements of stress of V 2 O 5 thin films during 50 electrochemical cycles. Surprisingly, electrochemical cycling appears to induce elastic and rate-independent deformation over a voltage range relevant to battery operation (4–2.8 V). However, the compressive stresses gradually increase with cycle number during the first few cycles, likely due to side reactions and/or residual Li left in the V 2 O 5 , even after delithiation (to 4 V). Further cycling leads to accumulated mechanical damage ( e.g. , fracture, delamination) and structural damage ( e.g. , amorphization), which ultimately result in severe capacity fade.  more » « less
Award ID(s):
1809866
PAR ID:
10161693
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Journal of Materials Chemistry A
Volume:
7
Issue:
41
ISSN:
2050-7488
Page Range / eLocation ID:
23922 to 23930
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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