Switch solar panels between grid-tie and charge controller

[Iuse2No]

I have a small 400 watt 24v system used to charge a single SOK LiFeP04 12v 100ah battery. This battery satisfies the power needs for my garage. However during the day the battery will fully charge and the system is doing nothing for several hours. When my battery becomes full I'd like to switch the panels over to my grid-tie inverter until the battery needs to be re-charged at witch point switch back to the charge controller. I researched several automatic transfer switches that will transfer to battery backup if grid goes down, but have not seen an ATS that will go between the grid-tie inverter and the charge controller in the fashion I'm looking for. Would appreciate any help with this. Thanks