Characterization and Prediction of Polymer/Active Material Interface Failure in Battery Electrodes
Characterization and Prediction of Polymer/Active Material Interface Failure in Battery Electrodes
复制标题
电池电极中聚合物/活性材料界面失效的表征和预测
DOI：
10.1007/s11340-022-00924-9
复制
发表时间：
2023
影响因子：
2.4
通讯作者：
Nadimpalli, S. P.
中科院分区：
文献类型：
--
作者：
Pakhare, A. S.;Nadimpalli, S. P.
背景商业复合电极中聚合物/活性材料界面的失效是电池容量损失的机制之一。尽管很重要，但目前还没有系统的研究来表征和理解电池电极的界面失效行为。目的开发一种表征可充电电池系统中聚合物/活性材料界面断裂行为的实验方法。方法通过一系列纳米加工工艺在SiO2表面沉积PVdF（聚偏二氟乙烯）聚合物来制备轴对称泡罩测试样品。然后将 PVdF/SiO2 样品在新型电化学电池中加压，直至薄膜与 SiO2 分层。测量了加压薄膜的机械响应，并用临界能量释放率Gc 来表征PVdF/SiO2 界面断裂。对断裂表面进行分析以确定失效机理。结果断裂表面的X射线光电子能谱和扫描电子显微镜分析表明，裂纹路径主要位于PVdF/SiO2界面，即失效机理是粘合性的。因此，测得的 Gc= 2.46 J/m2 可被视为断裂键以将 PVdF 与 SiO2 分离所需的能量。在有限元模型中使用该Gc值，成功预测了平面应变泡罩样品的失效压力。结论我们通过实验证明，Gcis是一个基本断裂参数，并且G = Gcas是一个失效准则，可以用来预测PVdF/SiO2界面失效，而与样品几何形状无关，并且可以扩展到电池电极。
BackgroundFailure of polymer/active material interfaces, in commercial composite electrodes, is one of the mechanisms by which batteries loose capacity. In spite of the importance, no systematic study to characterize and understand the interface failure behavior of battery electrodes exists at present.ObjectiveThe objective is to develop an experimental method to characterize the fracture behavior of polymer/active material interfaces in rechargeable battery systems.MethodsAxisymmetric blister test samples were prepared by depositing PVdF (polyvinylidene fluoride) polymer on SiO2surface with a series of nanofabrication processes. The PVdF/SiO2samples were then pressurized in a novel electrochemical cell until the film delaminated from SiO2. The mechanical response of the pressurized film was measured, and the PVdF/SiO2interface fracture was characterized in terms of critical energy release rateGc. The fracture surfaces were analyzed to determine failure mechanism.ResultsThe X-ray photoelectron spectroscopy and scanning electron microscopy analysis of the fracture surfaces showed that the crack path was predominantly at the PVdF/SiO2interface, i.e., the mechanism of failure was adhesive. Hence, the measuredGc= 2.46 J/m2can be considered as the energy required to break the bonds to separate PVdF from SiO2. Using thisGcvalue in a finite element model, the failure pressure of plane strain blister samples has been predicted successfully.ConclusionWe have experimentally demonstrated thatGcis a fundamental fracture parameter, andG = Gcas a failure criterion can be used to predict PVdF/SiO2interface failure irrespective of sample geometry, which can be extended to battery electrodes.
玻璃/环氧树脂界面的固有韧性和粘合机制
影响因子：
5.3
作者：
J. Greg Swadener;K. Liechti;A. L. Lozanne
通讯作者：
A. L. Lozanne
影响因子：
2.3
作者：
K. Kierzek
通讯作者：
K. Kierzek
影响因子：
3.9
作者：
Chen, ZH;Christensen, L;Dahn, JR
通讯作者：
Dahn, JR