Short answer: charge the battery, disconnect it (battery switch or remove the negative cable) so parasitic loads can't drain it, and store it per chemistry: LiFePO4 partly charged (often around 50–70%, check your maker) and lead-acid fully charged on a maintainer.
Step by step
Note the resting voltage and compare it with the voltage chart.
Charge to the right level for your chemistry.
Turn off the battery disconnect, or remove the negative cable; detectors, stereos and inverters drain batteries over months.
Clean terminals and check lugs are tight.
Lead-acid: connect a maintainer suited to the chemistry. Lithium: only use a maintainer if the maker allows it.
Check the voltage monthly and recharge if it drops (LiFePO4 only when above freezing).
In spring, charge fully and test under load before your first trip.
Yes. Parasitic loads like propane detectors and stereos can drain a battery over a few weeks; use the disconnect switch or remove the negative cable.
What charge should LiFePO4 be stored at?
Many makers suggest storing around 50–70% state of charge; follow your battery's manual.
Can RV batteries freeze?
Discharged lead-acid batteries can freeze and crack. LiFePO4 tolerates storage below freezing better but should not be charged below about 32°F unless it is self-heating.
Safety: These are general estimates, not a design. Follow your equipment manufacturer's instructions and local electrical code, and consult a qualified electrician for anything connected to shore power, a house, or high-current batteries.