The OAS framework integrates battery models using component and state adapters. The component adapters interact with the components by preparing the necessary inputs to run the components and by scheduling the component runs. The state adapters interact with the battery state file(s) by updating all the necessary information about the battery state and the methods for coupling the components. [@Fig:battery-state] shows a battery state file that transfers the information between the electrochemistry, thermal and electrical physics components. The device hierarchy is modeled by coarse-graining of the underlying sub-components. The top hierarchical level of the model is divided into zones. These zones then transfer information between the components in case of loosely coupled multi-physics simulations. Further description and examples of the battery state are given in the sections that follow.