Skip to content


ATV Battery Types and Maintenance Tips

The battery is one of the most simple and most complex components of your ATV. We deal with batteries everyday, whether it’s in a car or the TV remote. But like we mentioned in our post about Spring PMCS, we have to treat our ATV batteries differently than the batteries we are used to dealing with everyday. If the batteries in our remote die, we toss them. In a car, we’re used to letting the engine charge the battery and so we are used to dealing with it far less often. Unfortunately with an ATV we have neither of these luxuries. Due to the constantly fluctuating RPMs, the motor is an unreliable way to charge and maintain the battery. And let's face it, batteries aren't cheap. It’s entirely up to us to keep it properly charged and maintained. Considering the day-to-day experience that most people have with batteries, maintaining a battery can be confusing and even the most seasoned mechanics can be guilty of tossing a battery that they think is bad. With the right tools and a little bit of background information, battery maintenance doesn’t have to be so intimidating. By arming yourself with the knowledge and investing a small amount into the right tools, you can get the most out of every battery you own.

Know Your Battery

First things first, you need to know what type of battery you are dealing with. This will make a difference in where and how you charge the battery. An ATV battery can be one of two types: a wet cell or an absorbed glass mat (AGM). The wet cell battery has been used for a very long time. A wet cell battery is also known by several other names; typically involving something wet, such as flooded battery or lead acid battery. This used to be the most common battery type but in the last few years they have started being replaced with AGM batteries. If you have a wet cell battery, the first giveaway will be the fill caps on the top. Wet Cell

After a long day of riding through mud, a good clean up is in order. It's not uncommon for us to do a quick spray, throw the batteries on the charger, and bring them out again in the morning for a more thorough cleaning. So if you're batteries don't look brand new, don't worry. You won't get any judgement from us!

The next clue that you have a wet cell battery will be the vent tube that lets the battery breath. Wet cell batteries normally have a tube running out of the battery compartment. Wet Cell Vent If you determine that you have a wet cell battery, you will want to charge it in a well-ventilated area. The charging will cause the battery to heat up, which will produce a gas. This is normal but because the gasses are flammable, you don’t want them contained in a small area. You can use any charger on these batteries but as we pointed out back here, you do not want to quick charge these batteries. To keep from overheating and calcification, a 5amp charge is as high as you want to go. For example, the average ATV battery is 6amp hours. At a 5amp charge, it would take 1.56 hours to be fully charged. As the amperage increases, the time drops but the amount of heat rises. The dramatic rise in heat is what causes the battery to boil, which causes the acid to evaporate leading to calcification. (As well as smelling really really bad.) With a quick charge, not only is the acid being wasted, but the build up of calcification can cause the battery to short internally. If you are unsure what amperage and how long to charge your battery, try this charging calculator. (For reference, 1 amp = 1000 milliamp) After you have calculated the rate for your battery, charge accordingly, and let the battery rest. If it still will not stay around 12.6 volts, the battery is probably bad. (Remember, at this point we're still talking about a wet cell battery.) I would still recommend you have it checked at your local battery supplier. If you do need a new battery, and you purchase another wet cell, it will normally not be filled. You will need to add the acid and charge the battery. Some sellers will do this for you so be sure to ask if they will. If you do have to fill the battery yourself, make sure you do not over fill or under fill.

atv battery

After you fill your wet cell battery for the first time, give it about 10 minutes or so before checking the fluid level again. Sometimes there will be an air pocket and the battery will need to be topped off. Once you have topped off the battery you will need to charge it. Again, we like this charging calculator to help with amperage and charge times. After filling and charging the batteries, you will most likely have some acid leftover. We hate storing extra chemicals but this is one you should keep because everytime time the battery gets hot the acid will evaporate. Be sure to check the level monthly and add acid accordingly. The other type of battery that you may encounter is the AGM, or absorbed glass mat battery. In my opinion, these are the best type that you can get. They last longer, do not spill, and do not vent as much. They do cost more, but there are no smelly gasses, no ventilation needs, and no acids to refill. This battery can be identified by its labeling. The battery will normally say “sealed do not open”, “no fill”, or “no spill”. It may also be labeled as AGM somewhere on the battery but don't worry if you can't find the word "AGM" specifically.

atv battery

AGM batteries come with a base charge and will start and run your ATV right off the bat but to extend the life of your battery, it is better to put them on a low amp charge before use. If you have one of these batteries in your ATV and it is below 4 volts, depending on your charger the battery may not want to take a charge. But don’t give up on your AGM battery so quick, there is another method… If you have charged multiple times and still cannot get the voltage to come up, there is a trick to getting these batteries to take a charge. I learned this trick in a class on the new batteries the Army is using called Hawker made by EnerSys. For this to work, you will need a second good battery and jumper cables. First, take the dead battery and attach it to the good battery just like you would if you were jump starting it. Then take the battery charger and attach it to the bad battery also. I know these terminals are small and hard to get to, but you can get them on there or just hook them to the jumper cable leads. Again, these are small batteries and do not need or want a high amp charge. After about 30 min of running your charge in this set up, stop the charge, take the jumper cables off, and try to charge the battery again by itself. You would not believe the amount of batteries I have got to come back from 1 volt to a full 12.6 volts that others have condemned as a bad battery because they did not use this method.

Maintain Your Battery

Now that you know the differences between the types of batteries and the best way to charge them both, I want to talk about how to keep your battery fresh and ready for whenever you are. In my other post about Spring PMCS, I talked about our battery maintainer that we use regularly.

atv battery

I highly recommend a battery maintainer and I love our model. It is a very simple and plug and play. Most come with a hard mounted plug in that attaches to your ATV. Then when you get back from riding all you have to do is plug your bike in and you’re done.

atv battery

If you do not want to mount the other ends on the ATV, most models also come with a set of clamps to put on the battery temporarily.

atv battery

If a battery maintainer is not an option for you, but your ATV is going to sit for more than 30 days at a time, I would recommend you take the battery out. Store it in a climate controlled area if at all possible and be sure to give it a quick top off charge once a month. If this is not an option either, then you should at least unhook the battery from the ATV. This will keep the electronics from drawing your battery down. Don’t forget that if you have a wet cell battery you will need to pull it out once a month and check the fluid levels. Allowing the acid level to get low will cause the plates to calcify, building a crust on the plates. Eventually the crusts will come into contact with each other and cause the battery to short out internally. Batteries prices can vary depending on the size required by the make and model of your bike as well as the type, brand, and quality of the battery itself. Even at discount prices, most batteries are an investment. They are also one of the few parts unlikely to be damaged while you’re riding. When you have this much control over a component, it makes sense to be vigilant in maintaining it. It can cost some money up front to purchase a quality battery, charger, or maintainer, but with a few simple steps you can extend the life of every battery you own. Ultimately, your own maintenance practices are what will get you the most bang for your buck. So what do you think? Do you have any tips or tricks that you’ve learned over the years? Do you use a maintainer? Or do you have another method that you love?
Previous article A Look at The BEST ATV Service Manual