Just picked up an electric trailer jack (Hi Power 2500#) for the Prestige Trailer. I was going to wire it to the truck batteries (via a disconnect wire) but thought it might be better to mount a battery inside the tool box on the trailer that I already have mounted on the frame. Thought maybe someone has done this and can give me the pros and cons. Thanks.

I had one on my old Skater trailer. It was a major PIA. I replaced the battery that came on it halfway thru the first summer then another the next spring and when that one bit the dust in July i $hit canned it and put a hand jack on there.

Same problems on a skater trailer with the Atwood jack. Make sure to always turn the switch off and trickle charge in the spring. A battery is a must though because the truck wire is only to charge because of the small wire size.

Maybe the new ones are improved. I had the Skater from 97-99 so its been a few years. It was nice when it worked right but not worth the trouble for me.

That's why I was thinking that having a connection to the tow vehicle would be a good idea. (What's one more battery amongst the 27 I maintain now?) There's a manual handle that will adjust the jack it if the battery goes dead. Maybe I'll try the gell Cell system and if it craps out I'll wire it to the vehicle.

A buddy of mine did what you're talking about for his enclosed trailer. I "think" he wired it so that when the trailer was plugged into the truck, it only "charged" the battery; he also had a switch in there somewhere but I don't recall exactly what it's purpose was.
I don't recall if he had another battery inside, but he used a solar panel to keep one/both charged.

I have mine wired into the trailer plug. When it's pluged into the truck it gets power.

Did you run a heavier gauge wire all the way from the battery back or are you tapping into an existing powered wire on the harness at the trailer?

I tapped into the existing wire on the harness. I also made the harness about 3' longer so I can plug in and raise and lower the trailer.

Decided to hook it up to the wiring harness using the tail light wire. Works perfect!