How Long Do Jet Ski Batteries Last? Battery Keeps Dying?

You can expect a jet ski battery to last 3 to 5 years, but my personal best is 7 years.

There is a trick to getting your jet ski battery to last this long, and I’ll show you how in this post. Failure to do these simple steps could result in you having to buy a new battery every year.

Why Your Jet Ski Battery Keeps Dying?

The reason why your jet ski battery dies so often is due to you not riding it enough.

If you don’t drive your jet ski often, the lead-acid battery will sulfate. When a battery sulfates, it builds up materials on its plate that restrict the flow of electrons. With enough build-up, your battery won’t have enough amps to start your jet ski.

Since jet skis don’t have alternators like jet boats it’s charging system is different than your car.

Also, you tend to drive your car more often, which is why you don’t have the same problem with your vehicle. If you don’t drive your car for a few months, the battery on it will suffer the same fate. It doesn’t happen as quickly for vehicles because they use bigger batteries, smaller batteries sulfate quicker due to smaller plates.

How To Keep Your Jet Ski Battery From Dying

To keep your jet ski battery from dying, you’ll need to put it on a smart battery charger.

A smart battery charger will turn itself on and off as the battery needs it.

You only need to do this if you plan on not riding your jet ski for over a month. You’ll especially want to keep the battery on charge when you store the jet ski for the winter. I like taking the battery out and keep it on charge in the garage during the winter months.

What To Do To Get The Most Life Out Of My Battery?

The trick I do to get the most life out of my jet ski battery is to use a solar charger.

I like this method more than a smart battery charger because I don’t need to be near a power outlet, and the solar panel doesn’t need direct sunlight.

Yes, you heard me right. The solar charger doesn’t need to be in direct sunlight to work.

With the solar charger, the goal is not to charge the battery. In fact, don’t use the solar charger if the battery is completely dead – use a smart battery charger instead.

The reason why the solar charger works is that it keeps the battery from building up sulfate on the plates. The little bit of energy from the solar charger is just enough to keep the battery stimulated and alive.

While the solar charger doesn’t need to be in direct sunlight, it does need to get some sunlight. Keeping the panel in the dark all the time can have the opposite effect and drain the battery, so make sure it can get some sunshine.

To give you an example, here is a solar charger hanging off the side of a jet ski. It’s not getting direct sunlight, but it is getting some.

What Solar Panel Battery Charger Should You Buy?

You must buy the correct solar charger. You can easily overdo it and damage your battery.

You want a 5-watt or less solar panel charger. A 1-Watt solar charger is as low as I would go.

The solar charger also needs to be 12 volts; jet skis use a 12-volt battery.

Here is the solar battery charger I recommend getting on Amazon (Amazon Link Ad).

Do not, I repeat, DO NOT buy a solar charger that is over 5-watts. Going over this wattage will require a regulator, or else you will fry the battery. The great thing about these low wattage solar chargers is that it merely stimulates the battery and that is all you need. While a higher wattage will charge the battery but if nothing stops them from charging the battery like a regulator would then the battery insides get cooked. You want to stimulate the battery, not charge it.

When Do You Use The Solar Charger?

I like to keep things simple.

When I’m done riding for the day, I connect my jet ski to the solar charger. This is how I get such long life out of my battery.

Many solar chargers have quick connections, so it’s nothing to attach and detach the solar charger.

Can You Jump Start Your Jet Ski Battery

You should avoid jumping your jet ski battery from your car or truck.

You run the risk of frying your electronics on your jet ski if you do this.

It has nothing to do with the two batteries being different sizes, well this does play a role, but it’s not the biggest reason why you don’t do this.

The reason you avoid jumping your jet ski with your car or truck is that people are trained to jump other vehicles with the engine running. People carry this habit to jumping a jet ski, and that is what fries your jet ski electronics.

The charging system is much stronger on your car or truck, and when it sees this new load from your dead jet ski battery, your vehicle cranks up the power, which then overloads the jet skis electronics.

It’s best to avoid jumping a jet ski battery at all costs, to be honest. The battery on most jet skis is not hard to get to and replace.

If you’re in a pinch, you can use a jump box, but I don’t recommend it.

One More Thing…

The batteries you get from the manufacturer are simply junk. If done right, you can make them last, but manufacturers don’t ship the best batteries.

You want sealed gel-cell batteries.

These batteries hold up to the abuse that jet skis go through like shock, vibration, saltwater, and so on.

Battery Size

It’s also essential you get the correct size battery for your jet skis.

I can’t tell you how many people I’ve seen buy the cheaper smaller battery thinking it will do and later find out their jet ski runs funny.

The 3 most common jet ski battery sizes are 30, 16, and 20.

Your current battery will say the size somewhere on it. Here is a picture of where the battery size is often located.

This video does a great job of explaining battery sizes if you’re interested. It’s a video for car batteries but it’s all the same.

I like sticking to these model of batteries… ETX30L, ETX20L, and ETX16L.

What Battery Do You Need?

Manufacturers are always changing up battery sizes, so you must check the current battery you have now to know what size to get.

To help give you a general idea, I’ve listed some options below.

Usually, the size 30 batteries was for Sea-Doo’s made from 2002 to 2016.

The size 20 is for…

  • Kawasaki
  • Yamaha
  • All Sea-Doo Sparks
  • Sea-Doo 2016 and up

A size 16 battery can be found on…

  • Most 2-Strokes
  • Some Yamaha
  • Some Kawasaki

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