Storage options for lead acid batteries.. Depend somewhat on "how long" and "How old" and "how cold"
If you have power to the RV's storage position and a good 3 stage converter charger. Simply plug it in and leave connected.
Else:
New batteries for just a few months. FULLY CHARGE and disconnect all wires connected to the NEGATIVE terminal (NOTE with six volt pairs that's the most negative, ignore the jumper wire)
Longer.. Consider hooking up a battery maintainer.
Expected lows below -40 Remove (Tie all wires connected to the Negetive terminal together, likewise tie all wires hooked to POSITIVE together.. that way you remember all of 'em come spring)
Insulate the positive wires (Saran Wrap multi layers)
Take batteries inside, set on scrap wood to protect whatever surface is BELOW the scrap wood from any acid and hook up a battery minder.
