Iwire, normal power or generator power, any emergency lighting wall packs and exit signs for egress have battery backup...right
Unfortantly no, that is not required.
IMO what you describe is good design.
When the utility drops you can be in darkness for up to 10 seconds until the generator comes on line.
To be clear here, if you have a building with a true Article 700 emergency system powered from a generator there is no requirement to have battery back up of the egress lighting.
Typically the emergency lighting in a building with a generator is the same lighting fixtures used for general illumination.
If you have 2 x 4 troughers lighting an area some of them will be fed from the emergency system.
If you do this in an area with HID lighting you must provide lighting that will cover the time for the lamps to cool and re strike.