RV Battery Care Through an Alberta Winter

Most RVs run on lead-acid house batteries, either flooded, AGM or gel, and some newer rigs use lithium. Whatever the type, a battery loses charge on its own while sitting, and small draws from the RV itself (propane detectors, stereo memory, control boards) speed that up. Over a long Calgary winter, a battery that was full in October can be badly drained by spring.

A drained lead-acid battery is also at risk of freezing. A fully charged battery holds up well in deep cold, but a discharged one has more water in the electrolyte and can freeze, which cracks plates and cases. That is why the goal all winter is simple: keep the battery charged and keep it from sitting flat.

Cold does not do the same damage to lithium batteries, but most of them should not be charged when they are below freezing, so they need their own approach. Check your battery's documentation if you are not sure what you have.

Start by fully charging the battery before storage. Then disconnect it from the RV. Many rigs have a battery disconnect switch, but be aware that some circuits can stay live even with the switch off. Pulling the negative cable is the surest way to stop the slow drain.

If your RV is in an unheated storage lot around Calgary, consider removing the batteries and keeping them somewhere cool but not freezing, like a garage. Set them on a shelf or a piece of wood, keep the tops clean and dry, and check the terminals for corrosion. If you leave batteries in the RV, make sure the compartment is dry and the connections are tight.

For flooded batteries, check the water level before storage and top up with distilled water only if the plates are exposed. Do not overfill. Wear eye protection and gloves, and if you are not comfortable doing this, it is a quick job for a shop.

A smart maintenance charger, sometimes called a battery maintainer or float charger, is the easiest way to keep a stored battery healthy. It tops the battery up and then holds it at a safe level without overcharging. A basic old-style trickle charger that never shuts off can cook a battery over months, so a modern multi-stage unit is worth having.

If you cannot leave a charger connected, plan to check and charge the battery every month or so. Use a voltmeter or the charger's readout. A fully charged 12-volt lead-acid battery rests around 12.6 volts or a bit higher; if it has fallen well below that, charge it right away rather than letting it sit.

For lithium batteries, follow the maker's storage guidance. Many recommend storing at a partial charge and only charging above freezing, and some have a storage or sleep mode built in. Whatever the type, a mid-winter look at the terminals and battery box is a good habit, and it is a good time to peek at the roof and seals while you are there.

Batteries wear out no matter how well they are treated. Signs it is time include a battery that will not hold a full charge, drops voltage quickly under a small load, needs water constantly, has a swollen or cracked case, or is several seasons old and has been run flat more than once. Chasing a weak battery with charger after charger through the summer costs you camping days and can stress your converter and other equipment.

Replacing a tired battery in the spring is usually cheaper than a service call at a campground, and far cheaper than a spoiled trip. If your battery is failing, it is worth having the charging system checked at the same time, since a faulty converter or a bad ground can quietly kill a brand new battery.

If you are in Calgary or anywhere in Alberta and are not sure whether your battery is worth keeping, Horton RV Services can load-test it, check the converter and wiring, and let you know honestly whether it is a charge, a repair or a replacement. We can also set up your rig for winter storage so the batteries make it through to spring.