At the moment I have 2 old group 29 deep cycles, and 3 fairly new ones.
*Walmart deep cycle batteries. I am thinking about eliminating them for their current application. 36 & 24 volt trolling motors. I recently picked up a 36V volt 100ah lithium for that application.Two of them in parallel (the old ones even) can easily exceed the duty cycle of the Warn winch. Until last year I didn't even realize winches had a duty cycle, but the Warn cut out doing an off road recovery and I had to switch to snatch straps for the **second vehicle. I prefer a low impact recovery, but shock loading does work. To be fair the winch probably wouldn't have moved the second wheel in a safe direction anyway.
My thought is with short pulls and reasonable cool downs a single deep cycle on the trailer with it being charged by the truck should be more than adequate for most jobs.
Not to long ago I bought some plastic battery boxes from WalMart for a pair of those group 29s, and I had to use the included spacers to keep the battery from sliding around in the box. They would have easily held a group 31 or larger. They were the cheapest battery boxes I found for a temporary setup. I don't recall if I bought them in store or ordered them off the WalMart website. I'm thinking I picked them up in store because I was in a hurry at the time.
As to lithium batteries. I think they are probably best suited to long term low current applications like RVs, but they do have some that can push some current. Not enough in my opinion for cranking over anything more than small utility engines, but I've seen reviews of 12V LiFePo batteries pushing insane current for a short time before they shut off.
- I've found the Walmart deep cycles have a better life to price ratio than more expensive batteries. When I fished 2 - 4 tournaments (sometimes 5 if you count Wednesday afternoon buddy tournaments) a month a set of group 31 AGM batteries lasted a around 3 years of hard use for. At a fraction of the price the Walmart group 29 deep cycle batteries lasted about 18 months and Walmart would replace them for free when they died. I don't think the warranty is as good as it used to be, but I have had deep cycle Walmart batteries replaced for free as recently as 2 or 3 years ago. As a side note I use a Walmart brand type F in my John Deere and it far outlasts the exponentially more expensive John Deere batteries. Since 2007 the Deere battery died in 2010, and I am on only my second Walmart battery since. I keep thinking its time for it to die and the tractor just keeps starting. As a second side note: The older
** Somebody attempted to rescue a vehicle gone off the "trail" on the side of a sand hill down by the river, and got themselves stuck. He had such a crappy attitude if I didn't need to drag him out of the way to get to the other guy I would have left him there. I'm going to miss that old white Chevy.