j par.
Battery in trunk means you should use some sort of 'sealed' and probably a gel cell or AGM battery unless there is a dedicated box and vent to outside.
Optima is just one of many manufacturers of such batteries.
It's unlikely the car's equipment will draw down the battery like one would do when trolling on electric power in a boat. Your ammeter will clue you in to whether this is the case. No ammeter? Then assume for now that's not the case because you've said nothing about trouble starting or eating batteries. I know for drag racing some people will purposely run on battery only. So there, maybe. Otherwise, a battery for starting is the important thing.
What we are reading on Classic's website has a big red flag that its marketing BS written by someone who has no idea.
AGM is a battery made with liquid acid in an Absorbant Glass Mat
Gel-Cell is, well, an acid in gel form.
As far as the instructions go, its a little hard to know quite what they mean.
It says charge the battery to maintain 12.84 Volts. That's different than charging at 12.84 Volts.
To reverse the chemical reaction that occurs during discharge, connect to a power source at a slightly higher voltage.
All car batteries that we use should be around 12.8 Volts when fully charged and in good condition.
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Cranking Battery vs. Deep Cycle Marine Battery
Wayback Machine see especially sec 7.1.8 for deep cycle vs starting, and 7.1.7 for gel cell
(just poking fun)
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