Model-Based Investigation of Porosity Profiles in Graphite Anodes Regarding Sudden-Death and Second-Life of Lithium Ion Cells

Batteries

Daniel Müller¹  KaiPeter Birke¹  Thomas Dufaux² 

[1] Electrical Energy Storage Systems, Institute for Photovoltaics, University of Stuttgart, Pfaffenwaldring 47, 70569 Stuttgart, Germany;Robert Bosch GmbH, Product Area Battery, Kruppstrasse 20, 70469 Stuttgart, Germany;

关键词: Li-ion cells;    ageing-induced lithium plating;    sudden-death;    second-life;    modelling;    porosity profiles;    graded porosity;    graphite anode;   

DOI  :  10.3390/batteries5020049

来源: DOAJ

【 摘 要 】

The second-life concept helps to reduce the cost for electric vehicles by adding monetary value to disused automotive batteries. However, the sudden-death effect, a change in ageing behaviour limits the total lifetime and might reduce the second-life timespan. In this paper, we utilize a common pseudo two-dimensional (P2D) cell model to investigate the influence of different porosity profiles in the graphite electrode on the battery’s ageing. Ageing is modeled by two irreversible side reactions at the anode, the formation of solid electrolyte interface (SEI) and lithium plating. We use parameters of a high-energy cell with thick electrodes. A constant initial anode porosity as a reference is compared with two optimized porosity profiles. Simulation results show that by using a layered anode, a two-stage porosity profile with higher porosity at the separator side, the cycle count until sudden-death and especially the cycles for second-life applications can both almost be doubled.

【 授权许可】

Unknown