How Do You Charge a Jet Ski Battery? [Video Guide]

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One of the most annoying issues is if you are looking forward to a thrilling ride, but your jet ski won’t start due to a discharged battery.

Maybe it just wasn’t used for a while or your battery is getting older.  There could be several reasons why you have to charge your jet ski’s battery!

That’s why you have to start your ski in your garage as part of the pre-ride check before heading to the waterfront! Eventhe best jet ski batteries can be discharged if you don’t take care of them.

Charging a jet ski battery is not hard, but there are some important things to keep in mind. Doing it wrong can damage your battery or even the jet ski’s electronics.

If you want to learn more about jet ski batteries, don’t stop reading here. We, at JetDrift, have collected the best tips on how to charge, store, maintain, and replace a jet ski battery properly.

How Do You Charge a Jet Ski Battery?

How Do You Charge a Jet Ski Battery?

To charge a jet ski battery properly, the key points are to always remove the battery from the jet ski, and charge it with a smaller smart battery charger to avoid overcharging. You may also want to charge the battery slower; usually, a 1 Amp charger is plenty enough.

Just like car or motorcycle batteries, jet ski batteries can be charged with an appropriate charger.

For your convenience, we’ve compiled a general step-by-step guide on how to charge your jet ski’s battery. But before you do, make sure to check your owner’s manual for more detailed, model-specific instructions!

1. Every manufacturer strongly recommends to always remove the battery from the jet ski if you want to charge it. Although it may seem more convenient to charge the battery in the ski, it can be dangerous in many ways. As the battery in your ski doesn’t need to be charged every day, it’s definitely worth the little effort.

2. Locate the battery in your ski and remove the access panels. Slide the rubber caps, and disconnect the cables from the battery. While you do this, make sure to disconnect the negative (black) cable first. Then disconnect the positive (red) cable and finally the breather hose if there is one.   Make sure about the right order, as doing it wrong may damage the jet ski’s electronics.

3. Finally, remove the straps and remove the battery from the ski. If your battery is mounted in a battery holder (bracket) you have to remove the whole bracket with the battery.

4. Once you’ve removed the battery, a quick check never hurts. Is it in good shape? If you can see any cracks or deformation, buy a new battery immediately! Don’t forget to check and clean the battery tray, as there may be some dust or sand in it.

5. Place your battery in a cool, secure place close to a power outlet. Make sure that you work in a well-ventilated area. Some batteries generate hydrogen gas from the sulfuric acid what has to be removed from the room. Additionally, keep away gasoline, matches, lighters and any other flammable materials from the battery and the charger.

6. Before you attach the charger, it’s recommended to clean the battery terminals to remove the corrosion. You can clean them with a mixture of one tablespoon of baking soda and a cup of water. Just stir them together, dip an old toothbrush into it, and scrub the terminals. If there is baking soda nearby, you can also clean the terminals with a wire brush. Make sure that they are perfectly clean and dry before attaching the charger.

7. Before charging, always check your owner’s manual for battery specifications and further guidance. Most of the ski batteries are 12 volts, but a double-check never hurts. Also, read the specifications of the battery charger, that provide details for safe use.

8. Make sure the battery charger is unplugged before connecting charger cables!

9. Hook up the charger’s positive (+) red cable first on the battery’s positive terminal.

10. Hook up the charger’s negative (-) black cable to the battery’s negative terminal.

11. Plug in the battery charger, and set it to the required charge rate. As a rule of thumb, the slower charge is always better for the battery. In general, 1 Amp is considered a good charge rate for jet ski batteries.

12. It’s recommended to use a smart charger, which detects when the battery is charged, and automatically shut off or switches to maintenance mode. Be careful as not every charger has this feature!

13. Always place the charger far from your battery. The best practice is to place it as far as the charger cables allow it.  It’s also important to note that while it’s charging, you should leave the battery, the charger, and the cables in one place.

14. Once your jet ski’s battery is fully charged, always turn off and unplug the charger first.

15. When removing the cables from the battery, make sure you remove the negative (-) black cable first, then the positive (+) cable.

16. Finally, reassemble the jet ski battery. Always secure the battery to its place with the straps first, and make sure it’s fixed properly.

17. When it comes to the cables, always connect the positive (+) red cable first to the positive terminal, and finally attach the negative (-) cable to the negative terminal.

18. Double-check the colors of the cables before you attach them, as reversing the connections will damage your jet ski’s electrical system!

19. Tighten the terminal screws securely with a wrench and move the cables from side to side to make sure that they don’t move.

20. You can apply a lubricating spray or grease to protect the terminals.

21. Don’t forget to cover the terminals with the rubber caps, and attach the breather hose.

22. As the last step, secure the removed access panels (if you’ve removed any).

But again, before you start the process, always refer to your owner’s manual for your manufacturer’s recommendation about the proper battery maintenance!

How Long Does It Take to Charge a Jet Ski Battery?

Another common question is how long does it take to charge a jet ski battery?

When it comes to charging, the rule of thumb is the slowest charging time is better for the battery (don’t exceed 2 amps!). It means if you do it the right way, it takes several hours to charge a jet ski battery. If the battery is dead, you probably will have to charge it overnight!

But it always depends on the charge rate, battery type, and its current level. Let’s see some examples!

How many amps is a jet ski battery?

A jet ski battery usually holds 12-30 amps, depending on the make and the model. The batteries in the latest PWC models tend to be 18-30 amps, but for exact specifications, always check the sticker on the current battery or your owner’s manual.

How long does it take to charge these batteries? It always depends on the charge rates and the charging level. Some examples:

If you have a half-charged 12-amp battery, a 2 Amp charger can fully charge it in 3 hours. But if it’s dead you will need 6 hours to charge it completely.   But experts say that a 1 Amp charger is a much better choice for these small batteries, but with this charger, you will need twice the time.

Let’s check the same issue with a 30 Amp jet ski battery. If you use a 1 Amp charger, it can fully charge a half-charged battery in 15 hours, and a zero-charged battery in around 30 hours. If you find it too slow, you can consider a higher charging rate, but as a rule of thumb, never exceed 2 Amps when you charge a jet ski battery!

How long should you charge a jet ski battery?

As you can see, you will need many hours if you want to charge your battery properly. Although most of the chargers offer “quick charging”, many experts say that you should charge a jet ski battery overnight. It’s because fast charging negatively affects the battery’s lifetime! In general, it’s best if you stick to the smart 1 Amp chargers, and charge your battery overtime or even more.

But is it possible to overcharge a jet ski’s battery? Don’t hesitate to read more to figure it out!

Can You Overcharge a Jet Ski Battery?

You may be wondering if it’s possible to overcharge a jet ski battery or not. The bad news is that unless you have a smart charger, you can overcharge your battery if you leave it on the charger for too long, or use a too-high charge rate.

But what are the risks of overcharging a battery? First, your jet ski’s battery can get damaged from being overcharged, but unfortunately, this is not the worst scenario.

Another side effect could be if the battery boils the mixture of distilled water and sulfuric acid. And another issue could be if the battery’s case gets hot, or in the worst case, it starts to swell or even melt.

Moreover, in the battery’s sealed cells, flammable hydrogen gas can be generated which can lead to many serious accidents. In the worst case, the battery can explode if the accumulated hydrogen is ignited by an electric spark. Of course, this is the worst situation in an overcharged jet ski battery, but this is a risk that exists.

That’s one of the reasons why every manufacturer recommends removing the battery from your jet ski, as the exploding battery can damage your ski in many ways!  It’s best if you use a smart charger, as it will not overcharge your jet ski’s battery.

Also stay under 2 Amps, as higher charge rates could damage or even destroy your battery.  If you have a regular charger, always refer to its manual as well as the battery’s manual.

How Often Should You Charge a Jet Ski Battery?

When it comes to battery maintenance, you probably would like to know how often you should charge a jet ski battery. The good news is that if you ride your ski frequently and the battery is in good condition, it means you should charge your jet ski’s battery during the winter. This is because when you ride your jet ski, it will charge your battery automatically. But if you ride it infrequently, the battery can discharge itself.

To avoid a complete battery drain, you may want to check your battery’s voltage weekly with a voltmeter. When you make the inspection, don’t forget that the jet ski needs amperage  beyond the voltage!

How many volts do you need to start a jet ski?

Jet ski batteries are usually 12 volts, but a fully charged jet ski battery should read above 12.6 volts (12.7-13+ volts). As a rule of thumb, you need at least 12-12.5 volts to start a jet ski, but it always depends on the model and some external factors. It’s best if you charge your battery if it drops below 12.6 volts!

When you check your battery, this reference chart may come handy to determine its condition:

Jet Ski Battery State Of Charge Reference Chart

Percentage of Charge12 Volt Battery

The self-discharge rate of your battery depends on some external conditions like ambient temperature and many others.

As a rule of thumb, every jet ski battery has to be charged at least once a month if your ski is out of use. It’s because the chemical reactions have to stay active in the battery, otherwise, it can easily be completely ruined.

Do you need to charge a new jet ski battery before using it?

When it comes to buying a new jet ski, buyers have several questions about the ski, and the battery condition is not an exception. In most cases, they are charged by the factory, which means you don’t have to charge a new jet ski before using it.

However, if you are a careful owner, you may want to make a quick check with a voltmeter, and recharge the battery before the first ride to get optimal performance.   If the ski has been stored at the dealer for several months, it’s not uncommon that the battery needs to be charged.

Another issue could be if the battery in the new ski is not factory activated.   If you are considering buying a new ski, you can ask your dealer to activate the battery if needed before you pick up your new ski. But in general, a good dealership will manage these for you without any request!

Can you jump start a jet ski battery?

It’s highly recommended to avoid jump starting a jet ski battery. It’s because there is a huge risk of damaging the jet ski’s electronics when you are boosting it with a car or other vehicle. Jump packs are also not recommended for safety reasons!

What Are The Best Jet Ski Battery Chargers?

What are the best jet ski battery chargers?

The best jet ski battery chargers are the smart battery chargers with charging rates no more than 2 amps. These smart chargers will turn off automatically when your battery is fully charged so you don’t have to be afraid about overcharging.

Consider a solar battery charger

Besides a regular jet ski battery charger, you can also consider a solar charger. These models do a good job if there is no electric outlet nearby. Moreover, you can take it with you on the water as there are many waterproof portable models on the market.


Solar battery chargers are less powerful than regular battery chargers. It means you can use them mainly to maintain the battery’s charge. Another limitation is that you can use them only during the daylight hours.

Can You Trickle Charge a Jet Ski Battery?

Can you trickle charge a jet ski battery? Although trickle chargers were common in the past, nowadays it’s not recommended to trickle charge a jet ski battery. In general, the battery tenders do a much better job on jet ski batteries than trickle chargers.

Is a trickle charger the same as a battery tender?

No, battery tenders are not the same as trickle chargers. The difference is that trickle charging means to charge the battery slowly but continuously even if it’s fully charged to avoid self-discharging. In contrast, a battery tender allows your battery to self-discharge and turns on to charge it when the battery’s charge drops below a certain level.

Moreover, if you use a trickle charger, there is a risk to overcharge your battery which can damage it in many ways or can even destroy the battery.

Does your jet ski need a jet ski battery tender? 

Battery tenders (known as float chargers) are the best way to maintain your jet ski battery especially during the winter months. But don’t forget that you have to remove the battery from the hull, even if you want to use a jet ski battery tender!

It’s also wise to check the battery during the process. Although a battery tender works automatically, it’s recommended to check it and the battery to make sure that everything goes well.


Charging a jet ski battery is not too difficult and very similar to charging a car or motorcycle battery. But before you do it there are a few things to consider.

First, contrary to popular belief, you always have to remove the battery from the jet ski if you want to charge it. When a battery is charged, sulfuric acid may leak from their cells, it can overheat or in the worst case, it can explode in your ski. It’s simply not worth the risk!

Once you remove the battery from the ski, place it in a secure place and attach the charger to it. While you’re working, always double-check the polarity. If you mix the cables, it can damage your battery and the jet ski’s electronic parts.

The best practice is to use a small smart charger with a 1 Amp charge rate. In general, a 1 Amp charger can fully charge a jet ski battery from zero charge in around 24 hours (or even faster).

But it always depends on the battery’s charge level, condition, and type. Jet ski batteries usually hold around 12-30 amps; the newest models typically need a 30 Amps battery.

If you don’t ride your ski for a while and the battery drops below a certain voltage, it should be charged. This limit may vary depending on the battery’s type and condition, but some jet ski manufacturers recommend around 12.6 volts. It’s also recommended to remove a jet ski’s battery for the winter months.

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