Modeling of complex electrical devices

Good day.

My question is about right and accurate modeling of complex electrical devices. For example, I want to describe in IFC 4.3 format AC-DC power supply like in this series (Ubiquiti/ EdgePower or Helios Power Solutions/SR250HL).
Power supplies like this are widely used in security, fire safety systems and other. In this device we can see three functional blocks - AC-DC converter, Battery, Controller. I have no special class of ifcProduct to describe and modeling this complex device. Hence I must describe this device like IfcTransformer.RECTIFIER, IfcElectricFlowStorageDevice.BATTERY, IfcController.PROGRAMMABLE with logical ports and interfaces from its own classes.

And after that, I must describe the relationship between parts.
IfcTransformer.RECTIFIER and IfcController.PROGRAMMABLE contained in one shelf and sold like one device. Hence, they have an ifcRelNests relationship between.
IfcElectricFlowStorageDevice.BATTERY sold as an optional component (and replaceable). Hence, the relationship between this part and other must be ifcRelAggregate.

Is that complex description of one device accurate? May it be more simple?