I recently added a second battery to my Z800. I didn't do it in a conventional way or the "best" way, but I did it in the way that worked for what I wanted. I ran into an issue last year when my battery was getting weak that it would not start a couple times, sometimes right after a ride or after using the winch. It is a PITA to jump start these things having to take the battery cover off and what not and you really aren't supposed to jump start them anyway. So I wanted a second battery, but I didn't want it hooked up all the time in case there was ever a draw on the system. So I used the extra battery slot under the seat for the spare. I hooked the positive directly to the main battery. I took one of those battery disconnects they use for boats that has the red key and I drilled out a spot in the other box under the seat that doesn't have the cover and ran the negative from battery to the switch to the main battery.  The was cheap and fairly easy. Ideally I would have used and isolator and all that but it just want' worth the extra money to me for what I wanted. Now essentially I have a jump start battery or easily accessed battery to charge both batteries and some piece of mind if I use the winch a lot.

 Sounds like a good idea. I will be plowing snow at our cabin with mine this winter and I'm a little concerned about the battery.

That is a great idea! I just posted about a quick connection set up that I created to address the same problem! That battery location and cover will teach you how to cuss! I accidentally ran the battery dead and had one hell of a time jumping the battery to get it started....Which made me think this BS needs to be corrected! My solution still requires hooking up another power source but yours is a simpler  self help solution! What battery did you use and what was the cost?

https://www.amazon.com/gp/product/B0022XTZO0/ref=oh_aui_detailpage_o08_s00?ie=UTF8&psc=1
Is the battery It is the factory battery I Actually bought 2 since my old one was dying anyway. None too cheap...

Owch!! I had no idea that these little batteries were so expensive! I think I will try using my lithium jump starter pack and see how that works for self jumping. Thanks for the link! I will save it in case the lithium power pack doesn't work well.

[2015 Z Force 800 53/Trail EPS]

Yeah I could have swore I saw those batteries much less somewhere...I need to start looking cause min's 4-years old now.

Yeah I could have swore I saw those batteries much less somewhere...I need to start looking cause min's 4-years old now.

I'm pretty sure they used to be less, like just over $100. Maybe it has to do with Trump tariffs. I was just lazy and didn't research to see if I could get a replacement with the same or better specs. it's such a tight spot you can't go bigger and I didn't feel like buying a mistake. 

[2015 Z Force 800 53/Trail EPS]

Yeah I could have swore I saw those batteries much less somewhere...I need to start looking cause min's 4-years old now.

I'm pretty sure they used to be less, like just over $100. Maybe it has to do with Trump tariffs. I was just lazy and didn't research to see if I could get a replacement with the same or better specs. it's such a tight spot you can't go bigger and I didn't feel like buying a mistake. 

Yeah...I know. It's tough to see when I didn't pay that for the huge RV batteries I just put in my camper.