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If you’re sitting in your RV and one of the worst possible smells suddenly assaults your nose, a smell that smells like rotten eggs, then there are a few likely culprits including your RV’s battery. While unpleasant, the rotten egg smell is a good indicator that something is wrong with your battery and it needs attention.
But why does my RV battery smell like rotten eggs?
If your RV battery smells like rotten eggs, it’s most likely because the battery has been overcharged, lacks ventilation, or has begun to corrode. It might be possible to fix your battery by replacing the charger, topping it off with water, or cleaning it, but you’ll probably need to purchase a replacement.
In this article, I’ll explain what’s happening to make your battery give off the rotten egg smell, how you can prevent it, and potentially fix the problem as well as some tips on how to get rid of the smell if it’s lingering.
What Is Making Your RV Battery Smell Like Rotten Eggs?
A breakdown of sulfuric acid into hydrogen sulfide is the cause of the rotten egg smell that’s coming from your battery. Hydrogen sulfide has the distinct smell of sulfur or rotten eggs.
This smell can be dangerous if you have inadequate ventilation or are breathing it in at a high concentration. There are some health risks like eye irritation and sore throats associated with breathing in hydrogen sulfide for long periods of time. So, it’s important to recognize and take care of the problem as soon as you notice it.
The most likely cause of your RV battery smelling like rotten eggs is your battery has been overcharged. Overcharging your battery causes it to overheat. The excess heat inside of your battery will cause evaporation of the water and sulfuric acid, which releases hydrogen sulfide producing the rotten egg smell.
There are a few other potential causes for your stinky battery.
The battery cells could be leaking the sulfuric acid components. This can be extra dangerous because sulfuric acid can cause burns and is corrosive.
If you’ve been on a break from using your RV for a while, or just purchased a used one that’s been sitting on the lot, your battery may have been unused for so long that the electrolyte inside has evaporated completely. Without the electrolyte, you’re left with thick sulfuric acid and nothing else.
Additionally, your battery terminals could be corroded. If that’s the case, the rotten egg smell will be quite strong, and the corrosion can cause the battery to short-circuit.
It’s also possible that your battery lacks proper ventilation, which can cause overheating and even fire. Or, your battery could simply be old. If it is, the chemicals inside are quite possibly breaking down and releasing the smell.
Regardless of the cause of the sulfur smell, you will want to be very careful when dealing with the problem. There are dangerous chemicals at play and you may want to consult with a professional before tackling this issue on your own.
How To Prevent Your RV Battery From Smelling Like Rotten Eggs
The basic premise behind preventing this from occurring is making sure that your battery is well maintained and frequently checking on it to make sure there are no issues.
You’ll want to periodically check your battery’s water level to make sure that it has enough so that the battery will not overheat. You can also use a battery vent cap to allow some gas to escape without letting excess moisture in. Both of these options will help prevent an excess of hydrogen gas from building inside of the battery.
If you notice any dirt or corrosion on the terminals, you should clean them with a wire brush.
The video below is a good overview of the regular maintenance you should perform on your battery to keep it running and in good shape.
You can also invest in a battery monitor that will help you keep an eye on how charged your battery is and will protect it from being overcharged.
Make sure that your battery doesn’t go too long without being used.
Use the 10% rule when you are buying a charger for your battery. That means the amp rating of the charger is 10% or less of your battery’s total amp hour rating. An oversized charger is the most likely reason for an overcharged battery.
Your charger might have a desulfation mode, in which case the rotten egg smell is normal and a sign that it’s working. When in this mode, the charger is basically overcharging on purpose to dislodge sulfate crystals that might have started forming. If your charger has this feature, it will either work automatically or you will have to press a button to start it.
How To Fix Your RV Battery When It Smells Like Rotten Eggs
If your battery is over three years old, your best option is to replace it. Your battery should have a lifespan of 3 to 5 years, so if it’s in that range, you’re safer to just get a new one.
If your battery is newer, then there might be a few things you can try to salvage it before having to spend the extra money on a professional or a new battery.
You’ll want to check the fluid levels of the battery. You can add more water if needed. Some batteries will not give you the option to do maintenance on them, so if that’s the case you may be in need of professional help or a new battery.
Clean the battery terminals and make sure all the cables are secure and in good condition.
You can also test the voltage of your battery to help give you an idea of exactly what the issue is. If your voltage is 14.5 or so your charger might be too powerful, and if your battery voltage is 15-16+ it might be in desulfation mode.
If you’ve caught the issue early, you can adjust by getting a charger with less amperage and that should solve the problem. We have a post on how to charge your RV’s battery that will help you do it properly.
If the smell persists though, you’ll probably want to start looking for a new battery or at least get a professional’s opinion.
Can AGM Batteries Smell Like Rotten Eggs?
AGM batteries or absorbent glass mat batteries can also produce a rotten egg smell, but it’s typically less potent than lead acid batteries.
How To Get Rid Of The Smell
No one likes the smell of rotten eggs. If your battery had been giving off the stench and you’ve got it fixed but the smell feels like it’s lingering inside of your RV there are a few ways you can get rid of it.
Keep in mind that if you’ve solved your battery problems and the smell is still hanging around there are other possible reasons for it. It could be coming from your black water tanks, a gas leak, or bacteria in your freshwater tank. You’ll want to make sure it isn’t one of these before continuing.
Smell can be a good indicator of something being amiss, so don’t ignore it. Remember to ventilate your RV because the smell can be harmful in large quantities so you’ll want to do this for your safety as well as to help air out your space.
Air purifiers and dehumidifiers can help get rid of stubborn stenches as well. If you’re able to, you can also use vinegar or baking soda mixed with water to wipe down any surfaces you know were impacted by the smell.
It’s most likely that once your RV battery starts smelling like sulfur or rotten eggs that it’s time to replace it. However, if the battery is new cleaning the battery, making sure there’s enough water inside, and ensuring that you’re using the correct charger can fix the battery.
The smell of rotten eggs coming from your battery can be dangerous, that’s why regular maintenance and proper care can help prevent the rotten egg smell from occurring.