Comparative simulation of thin-film and bulk-type all-solid-state batteries under adiabatic and isothermal conditions

Abstract

As a recently rising cell technology, all-solid-state batteries (ASSBs) have emerged as next-generation electrochemical energy storage devices, which can be classified into two main types: thin-film and bulk-type, according to their structures. Here, we present a comparative simulation of ASSBs employing thin-film and bulk-type structures by using three-dimensional (3-D) and pseudo-3-D electrochemical-thermal coupled models developed on an open-source platform, OpenFOAM. Our results reveal the main differences between two types of ASSBs in terms of voltage-capacity curves, temperature rises, heat generation mechanisms, effect of ambient temperature, and various internal resistance under isothermal and adiabatic conditions, respectively. The thin-film extracts around a third of the capacity of the bulk-type and shows stronger temperature-dependent behaviors at the same C-rate. At the investigated C-rates, the ohm heat always represents a tiny part of the total heat in the thin-film while a decisive role in the bulk-type due to its ohm resistance being nearly-two orders of magnitude higher than the former. Reversely, the charge-transfer resistance of the bulk-type is about an order of magnitude lower than that of the thin-film. Collectively, this work provides a fundamental understanding of thin-film and bulk-type structures.