I have an entire TackTick suite that I've networked to other stuff via T122 NMEA interface. Read all about it at this old forum post.

I take the instruments off and store them on brackets inside the boat when not in use. During winter storage, they sit on the windowsill in my home office and stay fully charged.

I have no 12V connected to any TackTick displays, only to the NMEA and Hull interface modules. There is a schematic link at the bottom of the forum post above to look at how it's wired.