There are many different types of batteries out there including NiCd, NiMH, Lead Acid, Lithium Ion, and Lithium Polymer. So, when it’s time to get a battery for your RV, how do you know what kind to get? Not all batteries are created equal and you want to ensure you get a deep cycle battery to run all the things inside your RV. But what is a deep cycle battery and why do you need this kind?
Lead Acid Battery
A deep cycle battery is what is called a lead acid battery. These batteries are made of cells that have lead plates surrounded by water and sulfuric acid. In each cell is a positive plate made from Lead Oxide, a negative plate made of Lead, and an insulating material between the plates. As the current is between them, electrons are taken from the positive plate by the negative plate. As this happens, soft lead sulfate from the water mixture builds up on the plates and begins to inhibit the ability to transfer electrons. In basic terms, a fully-charged battery has plates surrounded by a mixture of water and sulfate. A dead battery has plates covered in the sulfate and pretty much just water around them. When you charge the battery, the current removes the sulfate from the plates and puts them back into the water. The battery is then able to transfer the electrons again.
What makes a Deep Cycle Different?
All deep cycle batteries are lead acid, but not all lead acid batteries are deep cycle. There are two different types of lead acid batteries and if you have a motorhome, you’ll find that you have one of each! A starting battery is designed to deliver a powerful punch to get the engine started and a deep cycle is meant to deliver a lower current over a longer period of time. If you were to use a starting battery as a deep cycle, it wouldn’t be able to hold enough to be sufficient and may actually deliver too much current which can cause damage. The deep cycle battery has thicker plates, which increases the density of the electricity. These plates have more space in between them so there’s more area for the sulfate to fall back off of them, and then they have a space under the plates where that sulfate can gather until the next charge. This allows for the battery to be discharged more, recharged more times, and gives off a lower current that’s meant to be used as a constant power source.
Charging a Deep Cycle Battery
In order to make sure your deep cycle battery lasts, there are some things you need to know about charging them. First is that when you charge them, you need to ensure you do so all the way. If the charge is cut short, it will allow some of the sulfate to remain in the bottom of the battery or on the plates. The longer the sulfate sits, the harder it becomes. Eventually it can become so hard that recharging will not disperse it back into the water. This then disrupts the electrolyte mixture and the battery can no longer pass the electrons between the plates. You also never want to let a deep cycle battery drop below a 50% charge. This will let that sulfate on the plates creep up them in a thinner coating and then become hardened and prevent the charge. Your battery should be able to be fully discharged and recharged between 200 and 300 times. Most of them are meant to last for up to 10 years. Many RVers find that the life of their deep cycle battery is cut short and the majority of the time this happens because of improper charging. If you plan to store your rig for the winter, or not use the battery for a long period of time, you still want to keep an eye on the charge. The sulfate will sink in the water mixture as it sits and then you end up with most of it at the bottom. This also presents an issue with the transfer of electrons. Keeping it charged will keep them dispersed so that the battery is ready when you need it!
Lead acid batteries are the oldest type of batteries we have today. They were invented in the 1900’s and survived not only because they work well, but also because they’re cost effective to make! These batteries do pose an environmental risk if not disposed of properly. If you have a lead acid battery that is no longer accepting a charge, be sure to recycle it! Instead of ending up in a landfill, it can be taken apart by a professional, and each part can be recycled to make a new battery. The plastic and plates are melted down and new ones are made, and the crystals from the sulfate can be used to make glass and other products! Now that you know what a deep cycle battery is, you can feel confident in choosing the right kind of battery for your RV, maintaining it properly, and taking care of it responsibly when it comes time to get a new one.