How to Keep Your Camper Battery from Dying Over the Winter

I hate to tell you, but summer is almost over.

Okay, yes, technically, it’s summer until September 21 at 11:59 p.m., but we don’t feel like summer is behind us once August is over. The children will be back to school, the beaches will be deserted and you will think of wintering your caravan.

If your vehicle battery often runs out of juice during the cold months, you may be wondering how to keep it from dying during the winter.

The short answer is to prevent its load from falling too low while avoiding overcharging.

If you want a more detailed answer and helpful tips on how to avoid a dead battery, read on.

What happens if you overcharge a battery?
I prefer to compare the battery of a motorhome to one of the batteries that most people know: the battery of a smartphone.

How many times have you been ready to go to bed to find out that your phone’s battery was dead? Probably a handful of times. I know this has happened to me several times.

What are you doing ? You plug in your phone and fall asleep. You know that when you wake up, your phone will be fully charged.

It turns out that what you do doesn’t help. You overcharge the battery.

What does that mean ? Well, the battery, even if it is fully charged, still receives so-called trickle charges. These are not full charges because the battery no longer needs them. But make no mistake: the battery continues to receive energy.

When the battery receives too many maintenance charges, its internal chemistry begins to change for the worse. It doesn’t matter whether it’s a phone battery or a motorhome battery. You still damaged it.

The effects tend to be more serious with a motorhome battery, it is true. Overloading it may cause it to fry. A burnt-out battery is unlikely to recharge. If so, it will certainly never reach full power again. This means it’s back to square one since you will need a new battery.

What happens if you let the battery die all the time?
Okay, you think. You don’t want to fry your motorhome’s battery, so you’ll be using it for as long as possible, maybe until it’s dead. This way, when you recharge it, it will take so long to charge until the end that there will be no overcharging.

You can get by once or twice with this mindset. More than that and you risk irreparable damage to your motorhome battery in yet another way. This time, the stability of the battery turns off. You end up again with a battery that does not fully charge.

No matter how many hours you let the battery rest, your motorhome will never be at 100% of its power. It’s pretty scary, isn’t it?

If you’ve let your motorhome battery die too often, the only solution is to buy a new one.

What is “Happy Medium”?
At this point, you understand that overcharging the battery is a no-no. Letting it die to the end and charging it is also not recommended.

Look, a battery will eventually lose its ability to induce and maintain a charge anyway. If you care, you can extend the inevitable for three, sometimes five, years. If you do not maintain the battery as you are supposed to, you could buy new ones every six or twelve months.

When your batteries are used during the active season, you must recharge them when they reach 50% of their capacity. In winter, when the batteries are not in your caravan, you have to recharge them even more often. You should not allow the battery to drop below 80%.

It may seem a bit counterintuitive to charge your batteries when they’re not even in use. What’s the point ?

According to Jim Tomblin of TruckCamper, every month you lose 10% of the capacity of your battery when it is not in use. It’s permanent, by the way. Recharging does not restore the battery capacity. If you were to winterize your camper in November and leave it until March, it would represent four months, or 40% of the capacity lost for good.

How to remove the battery from your motorhome
If leaving your battery on board your RV for the winter can cause short and long term damage, you will want to remove it from your RV for the off season. How to do ?

First of all, it is recommended to cut the direct electrical supply to your caravan using a disconnector. You can also (but not as easily) go through your caravan and turn off everything one by one, including televisions, fridge / freezer, other appliances, electronics and lights. The motor of your caravan must also be switched off.

A few minutes after cutting off the power supply, you can access the batteries through their hatch. Most battery doors have two cable terminals. One is red and the other is black.

You want to start with the black one. It is the negative cable terminal. In some cases, if the wing nuts that hold the terminals do not want to loosen, you can use pliers or a socket wrench.

Then loosen the red cable terminal, which is positive. Keep it away from the black cable terminal to avoid electric shock and possible damage to the vehicle. Once the wires are separated, you should be able to remove the batteries one by one. They can be heavy, so don’t try to remove them all at once!

Your batteries are now ready to be transported to a safe and dry environment where they can wait until the end of winter.

How to charge the battery outside your vehicle
I already mentioned how you should charge your trailer battery when it drops to 80%. This can happen more often than expected, about every two weeks. Sometimes it takes a full month, or four weeks, before needing to recharge.

The problem is this: normally, you use your vehicle while it is running or a shore power source to recharge your battery when your caravan is in use. And now what are you doing?

You can actually use a standard car battery charger to charge the batteries in your caravan. You must ensure that this charger is set to a maintenance charge or a winter charge. Otherwise, you risk supplying too much power to the battery at one time.

Remember that you only charge it at 20%. The battery will therefore not need a lot of power and should not remain on the charger for too long. Otherwise, you risk frying it, and we all know what’s going on at that time.

Replace the battery
Woo-hoo! You were super diligent and spent the winter charging the battery of your motorhome as soon as it was around 80%. Now it’s finally spring and you don’t need to use a car charger to recharge your battery.

Putting your batteries back in your caravan is not too difficult. You basically want to follow the instructions I outlined two years ago, but vice versa.

Put the batteries back in their compartment to start. Then replace the terminal of the red cable on its battery terminal. Do not touch the black terminal while you are doing this. Reconnect the wing nuts of the red terminal of the cable. Make sure the threads are not stripped and the nut is not too tight. If you have problems with the wing nut, it may not be the wrong time to replace it.

Do the same with the black cable terminal, connecting it to its battery terminal. Avoid the red cable terminal at the same time as you do. Tighten the wing nuts.

Then check the batteries. They must be securely in place in the compartment, without the possibility of moving or jostling. If they are good, you can then close the compartment cover, making sure it is properly closed.

Your batteries are now ready to use. Depending on what you have done to turn them off before, you will have to do the opposite. This could mean going through your vehicle and turning on lights, electronics and appliances. Otherwise, you will need to go to your breaker switches and test them to make sure the power is on.

Before you start driving, it may not be a bad idea to check the battery voltage. This is only possible if you have a voltmeter. This counter will inform you of the state of your batteries. For example, if your batteries can only receive between 10 and 11 volts of direct current (VDC), they will not last much longer. You may be able to get through the travel season by car with them, but there are no guarantees.

If you receive a low voltage message, it means that the voltage is less than 10 VDC. You can try to test the batteries again, but it is often necessary to replace them. The ideal would be to have 13 VDC batteries. They will allow you to cross the season and even beyond.

Most of the time, when it comes to batteries, most of the advice that exists is only for owners of recreational vehicles. It is true that the same care and maintenance protocols for recreational vehicle batteries apply to caravans, but not to all.

This year, when the time comes to winterize your caravan, you will know exactly what to do with your batteries to extend their lifespan.

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