PSI - Issue 22

Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000 – 000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000 – 000

www.elsevier.com/locate/procedia

www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 22 (2019) 251–258

© 2019 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of the First International Symposium on Risk and Safety of Complex Structures and Components organizers © 2019 The Authors. Published by Elsevier B.V.This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of the First International Symposium on Risk and Safety of Complex Structures and Components organizers Abstract The pouch cell is b coming ma nst eam amo g a variety of pow r ba teries, bec use of its high r energy density and lower weight. D e to the probability of gas production in a pouch cell, the in reasing inte nal gas pressure will caus strength degradation of the sealing area. This process significantly decides the safety and remaining useful life (USL) of a pouch cell. Thi paper valuates the strength d gradation of sealing adhesive area through accelerated degradation t st (ADT) and cohesive zone model (CZM), and provides a method to predict ng the s al ng life. In th experim n s, the load-displacement relatio was obtained. The mod fied xponential CZM w s u ed to describe the mathematical relation and the sealing strength degradation is evaluated by the loss of fracture energy. This modified model is validated well by the testing data. Evaluation of the sealing life can be predicted with the condition of internal gas pres ure. © 2019 The Authors. Publ shed by Elsev er B.V.This is an open access article u er th CC BY-NC-ND li ense (http://cr a ivecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of the First International Symposium on Risk and Safety of Complex Structures and Components organize s 2452-3216 © 2019 The Authors. Published by Elsevier B.V.This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review statement: Peer-review under responsibility of the First International Symposium on Risk and Safety of Complex Structures and Components organizers 2452 3216 © 2019 The Autho s. Published by Elsevier B.V.This is an open acc ss rticle under the CC BY-NC-ND license (http://c ativecommons.org/licenses/by-nc-nd/4.0/) Peer-review statement: Peer-review under responsibility of the First International Symposium on Risk and Safety of Complex Structures and Components organizers 1. Introduction The safety and reliability of energy storage devices is a key factor for the development of electric vehicles (EV). In a variety of power batteries applied in EV, the lithium pouch cell is a development tendency, because it has lighter weight, higher energy density, and flexible shape design. And one reason of these advantages is that the pouch cells * Corresponding author. Tel.: +8615801255999 . E mail address: z angwei.dse@ uaa.edu.cn Abstract The pouch cell is becoming a mainstream among a variety of power batteries, because of its higher energy density and lower weight. Due to the probability of gas production in a pouch cell, the increasing internal gas pressure will cause strength degradation of the sealing area. This process significantly decides the safety and remaining useful life (USL) of a pouch cell. This paper evaluates the strength degradation of sealing adhesive area through accelerated degradation test (ADT) and cohesive zone model (CZM), and provides a method to predicting the sealing life. In the experiments, the load-displacement relation was obtained. The modified exponential CZM was used to describe the mathematical relation and the sealing strength degradation is evaluated by the loss of fracture energy. This modified model is validated well by the testing data. Evaluation of the sealing life can be predicted with the condition of internal gas pressure. Keywords: pouch cell; strength degradation; CZM; ADT. 1. Introduction The safety and reliability of energy storage devices is a key factor for the development of electric vehicles (EV). In a variety of power batteries applied in EV, the lithium pouch cell is a development tendency, because it has lighter weight, higher energy density, and flexible shape design. And one reason of these advantages is that the pouch cells * Corresponding author. Tel.: +8615801255999 . E-mail address: zhangwei.dse@buaa.edu.cn Keywords: pouch cell; strength degradation; CZM; ADT. First International Symposium on Risk and Safety of Complex Structures and Components The experiment and modeling for sealing strength degradation First International Symposium on Risk and Safety of Complex Structures and Components The experim nt and modeling for sealing strength degradation evaluation of lithium-ion pouch cell W. Zhang a, *, M.X. Cheng a , Y.M. Liu a , H. Sun b a School of Reliability and Systems Engineering, Beihang University, Beijing, 100191, P.R. China b Contemporary Amperex Technology Limited, Fujian, 221116, P.R. China evaluation of lithium-ion pouch cell W. Zhang a, *, M.X. Cheng a , Y.M. Liu a , H. Sun b a School of Reliability and Systems Engineering, Beihang University, Beijing, 100191, P.R. China b Contemporary Amperex Technology Limited, Fujian, 221116, P.R. China

2452-3216 © 2019 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of the First International Symposium on Risk and Safety of Complex Structures and Components organizers 10.1016/j.prostr.2020.01.032