When you take a long break from jet skiing, or your jet ski shows low power signs, you should prioritize charging your battery. Unlike a car or motorbike, getting stranded with a dead jet ski in the middle of an ocean can be quite dangerous. You have to correctly charge your jet ski battery whether you use your jet ski often or not.

You can use a 1 amp capable smart charger to charge your battery. The Smart chargers are easy to connect and can be left charging for an extended period without the risk of overcharging. We will give you a detailed guide to assist with charging a Jet Ski battery.

Do Jet Skis Have a Charging System?

Yes, jet skis have a charging system, but it is not similar to a car’s charging system. A jet ski has a stator, while a car’s charging system is called an alternator. The stator will maintain whatever charge is there and not fully charge your jet ski like a car’s alternator.

So how does the charging system of a jet ski work? The ski’s charging system consists of the stator and a flywheel. The stator is a piece of electromagnetic equipment that generates electricity from the flywheel’s rotation, which turns the charging coil. This electricity powers the jet ski battery and accessories.

Therefore, if you start riding with a weak charge, the jet ski will produce enough power for the ride, but it will be dead when you restart it after some hours later. That’s why you have to be on the lookout for low power and recharge it immediately. Good battery maintenance involves you knowing when you should charge your jet ski battery. Some of these situations include:

  • Before installing a new battery. Typically, jet ski batteries are factory-charged, but if it has been idling at the store for a while, it may have a low charge. Check your battery’s voltage with a voltmeter and recharge it.
  • You’ll need to charge your battery if it’s dead. If you leave your jet ski idle for a while, the batteries will begin to sulfate—the plates on the battery build-up and cause it to lose charge over time.
  • Keep your battery on charge during winter when in storage. The cold and self-discharging with no battery maintainer will kill the battery.
  • Suppose your battery reads below 12 volts. Check on the battery model to confirm the ideal voltage for your jet ski battery to run smoothly.
  • If you buy a battery that is not factory activated. You have to get it activated by adding electrolytes into the battery, seal the battery with the plugs then give it its first charge.

How to Charge Your Jet Ski Battery

Charging a jet ski is as easy as charging a car, but it can seem a bit intimidating if it’s your first time doing it. If you do it correctly, you will not have any issues. If it is not a smart charger, then you run the risk of overcharging the battery.

It is crucial to read the instruction manual on your battery charger before using it, but here are the general guidelines to follow.

What You Need


  1. Take your jet ski to a dry and secure place away from any contact with water.
  2. You have to remove the battery from the ski to charge it. Locate the battery either in the front, middle or rear, and remove the access panels.
  3. Slide off the rubber caps on the terminals and disconnect the negative (black) cable to prevent damaging the jet ski computer. Then, disconnect the positive(red) cable and finally the breather cable.
  4. Cut the straps and remove the battery from its compartment. If your jet ski has a battery bracket, lift it together with the whole bracket.
  5. Wipe the battery plate and make a quick inspection to ensure the battery does not have any cracks or dents. If you do see any, buy a new battery.
  6. Place in a cool and secure spot, away from anything flammable like a lighter, matches, gasoline.
  7. Clean the battery terminals to remove any corrosion present. Mix one tablespoon of baking powder and a cup of water and use an old toothbrush to scrub. Alternatively, you can use steel wool. Make sure the terminal is completely dry before connecting the charger.
  8. Connect the charger’s positive(red) cable to the battery’s positive terminal.
  9. Connect the charger’s negative(black) cable to the battery’s negative terminal.
  10. Plug your battery charger into the wall socket or the water-resistant extension cord and set the appropriate charge rate. A slower charging rate is always the best. We recommend using 1 Amp for jet ski batteries.
  11. Before you leave, place the charger and the battery some distance apart. Then make sure the battery is charging. Most chargers have some kind of indicator like a LED light indicator.
  12. Once the jet ski battery is fully charged, switch off and unplug the charger first from the power source.
  13. Start by disconnecting the negative(black) cable first, followed by the positive(red) cable.
  14. Secure the battery back in the jet ski and then reassemble the connecting cables. Connect the positive(red) cable first to the positive terminal, then the negative(black) cable to the negative cable. Always double-check your connection to avoid damaging your jet ski’s electrical system.

 NOTE: The order of connecting and disconnecting the cables when charging is significant; you should never interchange the process. When connecting, you go with the positive cables first, and when removing, you disconnect the negative cables first.


  1. Secure the terminals tightly using a spanner and make sure the cables are not loose.
  2. Apply some lubricating spray or grease on the terminals to prevent corrosion, then cover them with the rubber caps, connect the breather hose, and access panel to the jet ski.

Best Jet Ski Battery Chargers

A smart charger with a charging rate of at most 2 Amp is the best option for charging your jet ski. It charges your battery and automatically turns off once the battery is all juiced up, preventing overcharging, which can damage your jet ski. Here are some of our best jet ski battery chargers.

Battery Tender Junior Charger and Maintainer

Battery Tender Junior Charger and Maintainer

This charger is the highest-rated and most popular smart battery charger on Amazon because it charges various batteries. It has a low maintenance design making it easy to use. It smart charges your battery sufficiently, automatically switches off, and then maintains the charge to prevent overcharging. It also comes with a five-year warranty in case it develops problems. It is spark-proof and has a 12-foot cord making charging convenient if the power source is not close. Its super-smart technology also checks for poor cable connection before giving power.


  • Charges and maintains
  • 12 Volts
  • 75 Amps
  • 5-year warranty
  • Spark proof
  • Reverse connection protection


  • Easy to use.
  • Automatic switch
  • Affordable


  • It requires electricity.
  • Not weatherproof

Solar Battery Tender by Deltran 021-1164

Solar Battery Tender by Deltran 021-1164

This battery charger uses solar power to charge your jet ski battery and switches off automatically. Solar power allows you to charge your jet ski anywhere without access to power. It is weatherproof and works in all daylight conditions.


  • 10W solar panel
  • 12 Volts
  • 54 Amps
  • Spark proof
  • Built-in temperature compensation sensor


  • Weatherproof
  • Affordable
  • It doesn’t require electricity.


  • It comes with a short cord of 5ft.

A Solar battery charger can be a good idea

A solar battery charger is a great choice when you don’t have a wall outlet near your jet ski. A solar charger is usually a maintainer, but it can charge your battery if you are in no hurry. Solar chargers are very convenient and easy to install. They are also weatherproof and do not produce sparks.

You can even mount your solar charger on your jet ski and use it to maintain your charge when riding.

When getting a solar charger for your jet ski battery, always choose a 1.8 to 5 watts solar panel. Any solar panel above 5 watts can fry your battery.

If you don’t have a wall outlet near your jet ski and keep them outside all the time, then a great option is a Solar Battery Charger.

How long does it take to charge a jet ski battery?

It takes about 16 hours to fully charge a dead 16 Amp jet ski battery at 1 Amp per hour. It may take you fewer hours when topping up. Ideally, the slowest charging time is better for the battery’s longevity. However, it always depends on the charging rate, charger type, battery type, and initial battery level.

Depending on the make and model, most jet skis carry a 12 Amp battery. If you’re charging a 12 Amp battery with a 2 Amp charger, it will take about 6 hours to charge it to 50%. But it is best to use a 1 Amp charger on such small batteries.

Check this too: How Old Do You Have to Be to Ride a Jet Ski?

Some smart chargers claim to be “fast charging,” but it should always stay under 2Amp when choosing a jet ski charger. Increasing the amperage will most likely damage the battery.

If you’re not using a smart charger, you have to check when the battery is full manually; otherwise, you run the risk of overcharging it. But what happens when you overcharge a jet ski battery?

  • Overcharging kills the jet ski battery.
  • The battery can get heated, boil and swell.
  • The battery will produce flammable hydrogen, which can cause many accidents.
  • If a spark ignites the hydrogen gas, an explosion can occur.

Are Jet Ski Batteries 6V or 12V?

All jet skis come with a standard 12-volt lead-acid battery, but they differ in amperage and size. They also hold around 12-30 amps. When fully charged, it can go all the way to 14 volts. Most manufacturers recommend that your jet ski battery should not go below 12.6 volts. After running your jet ski for a while, the amperage usually reduces and requires charging.

When replacing your battery, make sure you get the right size recommended for your jet ski model. The wrong size will drain your battery or wear down the jet ski electronics. There are also various types of jet ski batteries( discussed below) depending on cell composition. Regardless of the type you choose, it will most likely be a 12-volt battery.

Can You Trickle Charge a Jet Ski Battery

In the past, trickle chargers would charge your battery at a very slow rate continuously, even after full capacity, to prevent self-discharging. A trickle charger was connected when storing your jet ski for a long while and maintained the charge. The risk that comes with trickle charging is eventually overcharging your battery and permanently damaging it.

In recent years, trickle chargers have evolved into battery tenders. Battery tenders slow charge your battery to full capacity, allowing it to self-discharge, and then charges the battery when it falls below a specific limit. We recommend using battery tenders, especially during the long winter months. Though it automatically switches on and off, you should always check it regularly as machines are still bound to fail.

Why Does My Jet Ski Battery Keep Dying

Though jet ski batteries are relatively inexpensive compared to car batteries, it can be frustrating when you have to keep replacing or charging it more often than usual. So, here are some of the reasons your jet ski batteries keep dying.

  1. You are not riding your jet ski enough.

When your jet ski stays idle for too long, the battery will sulfate-the build-up of sulfuric acid. Sulfating weakens the battery. When you are not using your jet ski at least once a week, you should plug in a battery maintainer or battery tender to charge the battery when not in use.

When your jet ski starts, the battery discharges, meaning the current voltage in your battery reduces, but the stator maintains it during use; however, it does not increase the current voltage. Even if you use your jet ski often, charging it at least once a month is essential for optimum performance.

  1. Overcharging your battery.

Overcharging is a frequent mistake that users make when they are not using a smart charger. Leaving the battery charging for too long will overheat the acid and damage it. After a while, your battery cannot fully charge. Using a smart charger will automatically turn off when the battery is full and even maintain your battery when idle.

  1. Undercharging your battery.

You have to charge your battery at least once a month when not in use. It prevents sulfating by keeping the battery active. If you don’t charge it often, the battery will discharge itself. When charging, it is also crucial to ensure it charges to its maximum before using it. A fully charged battery reads above 12.6 volts on the meter; anything below 12 volts is too low.

  1. Incorrect winterizing

Most jet ski first-time users do not know that winterizing your jet ski battery is an important maintenance step. Most owners, including pro skiers, store their jet skis in the winter; however, proper storage is essential to ensure the battery’s longevity. Once in storage, you should take your battery from the jet ski, place it in a cool, dry place that won’t freeze, and then connect it to a trickle charger or solar charger. Get one with an automatic switch; you can connect it using the instructions above and forget about it until your next ride.

  1. Using the wrong charger.

Using the wrong charger for your jet ski battery will weaken it. You should not use a charger that has more than 2 amp. Do not also use your car charger on your jet ski battery. Jet ski batteries are small and require less amperage; otherwise, it might melt or overheat. We recommend using a 1 amp charger on your jet ski battery.

  1. Leaving the key on when the jet ski is not in use.

Always turn off your ignition switch and remove the key when you’re not using your jet ski. Leaving it in can cause your battery to discharge.

  1. Damaged battery

Your battery will not maintain charge if it is leaking or has corroded cables. Regularly check your battery to ensure it is in perfect condition. It can crack from the vibrations, or the wires can corrode from exposure to moisture. Even when buying a new battery, always check to see that it can reach the stated voltage. If your battery has been draining from the first stay, you probably got a damaged or low-quality battery.

  1. Wrong size battery

Battery sizes are not universal on all jet skis. Every time you replace your jet ski battery, always confirm your jet ski make and model and what the manufacturer recommends as the most suitable battery. Batteries come in various voltage and sizes. A battery that is too big or too small for your jet ski will drain your battery and even damage your jet ski operating system.

  1. A Faulty charger

Chargers also wear down or become damaged from a short fuse. A faulty smart charger will not fully charge your battery. Always check the voltage of your battery with a voltmeter every time you fully charge it. Usually, a fully charged battery should read above 12.7 volts, depending on your battery’s size.

 How Do I Know if My Jet Ski Battery is Bad

When your battery is failing, your jet ski will usually give several warning signs. You need to be aware of these signs early enough to either charge your battery or replace it. Otherwise, running around the waters with a faulty battery can leave you stranded or even damage the jet ski computer. Here is a list of the warning signs to be on the lookout for

  1. Slow-cranking: A slow cranking engine is one of the first signs that indicate a battery problem. When your battery is running low, it will not have enough power to turn the engine on as quickly as it should. Depending on the battery condition, the engine will crank slowly and then start; sometimes, it won’t start at all. You have to inspect your battery with a voltmeter or jump start it using a battery booster.
  2. The engine doesn’t start: If you turn the ignition and hear a rapid clicking sound without the engine cranking at all, it means your battery is low.
  3. The battery warning light comes on: Most jet skis nowadays have a large display on the dashboard. When there is a problem with your battery, the battery warning light will come on.
  4. Rotten egg smell: A standard lead-acid battery contains a mixture of water and sulfuric acid. When the battery starts to wear down, some acid and water may evaporate, causing a chemical reaction that produces a rotten egg smell. In worse cases, it can even start smoking. You have to replace the battery.
  5. No power to the jet ski electronics: a battery with low capacity will not hold enough charge to power the jet ski electronics. You will notice that turning the key does not activate the electrical system or power the lights.
  6. Old battery: If you have been using your battery for more than five years, it is too worn and will not hold a charge for too long. You should get a replacement.
  7. Corroded terminals: Corroded terminals can cause the jet ski computer to malfunction. If you notice an ashy substance on the terminals, disconnect your battery from the jet ski and clean it with baking soda and water. You can also scrub it off with steel wire.
  8. Loose or damaged connections: cables that are loose or damaged can lead to malfunction of the jet ski electronics. Broken cables can also produce a spark that can cause an explosion.

How Long Do Jet Ski Batteries Last?

A quality jet ski battery that is also well- maintained usually lasts about 3-5 years. You have to charge it regularly when not in use and winterize it correctly during cold months. When you don’t properly maintain it, it should last about 1-2 years.

Besides proper maintenance, other factors determine the longevity of the battery. These factors include:

  1. Type of battery

We have sealed AGM, lead-acid batteries, also known as wet batteries, and lithium-ion. AGM batteries are maintenance-free, spill-proof, vibration resistant, and less prone to self-discharge. However, they are pricier and do not last as long as regular batteries. Lead-acid batteries are more economical, have a longer lifespan than AGM but require regular maintenance. Lithium-ion batteries are less popular but have an extended shelf life and high capacity.

  1. Battery quality

Manufacturers determine the quality of the batteries they produce. Different models also have varying battery quality. The best quality is typically the most long-lasting battery; however, the price point should not dictate quality.

Check this too: What is the Fastest Production Jet Ski?

  1. Ambient temperature

The weather that is too hot or too cold can damage the battery and shorten its life span. Gel batteries can withstand high temperatures, while AGM does well in low temperatures.

Best Jet Ski Batteries

Jet ski batteries power your jet ski, and you should get a quality one for maximum performance. Here are out two best recommendations for the best jet ski batteries.

Chrome Battery YTX30L-BS High Performance

chrome battery ytx30l-bs

It’s a sealed lead acid battery with AGM technology. It is low maintenance and low self-discharge. This battery is well-sealed to prevent spillage and corrosion. It also has a reasonably long life span.


  • Battery Cell Composition: Lead-Acid, AGM
  • Watts: 360
  • CCA: 385
  • Volts: 12 volts
  • Amps: 30
  • Terminal Type: Steel Nut & Bolt


  • Affordable
  • Sturdy chrome exterior
  • Low maintenance
  • Has balanced output voltage


  • Steel terminals may rust without additional protection.

 Deka Power Sports ETX20L Battery

 Deka Power Sports ETX20L Battery

The Deka Power Sports ETX20L Battery has very high performance, durable season to season, and completely spill-proof. The absorbed glass mat (AGM) technology provides increased strength. This technology has highly porous microfiber separators that absorb and trap the electrolyte and maintain a charge.


  • Battery Cell Composition: Sealed Lead Acid
  • CCA: 310
  • Volts: 12 volts
  • Amps: 18


  • Its size can fit into most jet ski models.
  • Easy to connect
  • Value for money


  • Too lightweight


From this comprehensive article, you will have learned a lot about charging your jet ski battery. Charging a jet ski battery is quite an easy task. You will need to take out your battery to a dry area. Then connect it to a smart charger and wait for it to go off when fully charged. The charger should use 12 volts at 1-amps to charge your battery without damaging it. Additionally, with a solar battery charger, you have no excuse not to charge your battery when there is no power outlet in sight.