Best Dual Purpose Marine Batteries to Power Fishing Boats

When out fishing in a boat, it’s handy to have a marine battery with two functions, one as a starting battery, and another as a traditional deep cycle battery, since many electronic gadgets are typically run off the starting battery.  That’s where dual purpose marine batteries come in.

Dual-purpose marine batteries are capable of not only starting the outbound engine, but they also have enough power to keep all of your electronics ticking over throughout the course of a full day out on the water fishing.  To that end, dual-purpose batteries offer both great cranking power, and deep cycle power draws.

We’d like to show you our Top 5 dual-purpose marine batteries, and if you still can’t decide which one to buy, we also have a brief buying guide for you which explains what makes dual purpose marine batteries different to their single purpose counterparts and lays out for you what you should be looking for in your dual purpose marine batteries.

Best Dual Purpose Marine Batteries to Power Fishing Boats - Reviews

What we love about this dual-purpose AGM battery from SuperBatt is it’s affordability, coming in at a fraction of the price than some of the others in our Top 5 picks.

This Ultra Deep Cycle battery offers 4 times more cycles than a standard Leisure Battery.

This SuperBatt battery offers 850 cold-cranking amps, which will be more than enough for what you need to get the boat’s engine going when you need it to.

And there’s a capacity of 120AH to run all your boat’s electronics from your fish finders to your GPS system.

Its dimensions are 353mm x 175mm x190mm.  And, importantly, it’s an AGM battery (more on that in our buying guide).

It’s Fully Sealed and Spill-proof making it completely safe to use.

The other great thing about this battery is the warranty - it lasts for an entire 3 years in total.


  • Affordable
  • 850 cold-cranking amps
  • capacity of 120AH
  • Fully Sealed and Spill-proof
  • 3-year warranty


  • The dimensions are quite big with regards to the length, so before you buy please ensure that it will fit into your battery tray or compartment.

Now here’s a great dual purpose marine battery from Odyssey!

This beauty has 2 times the overall power and 3 times the lifespan of traditional marine batteries.  You could get up to 10 years out of it, depending on usage.

It offers a staggering 1150 cold-cranking amps, so with this in your fishing boat, you’ll never be left stranded in the water, and will always be able to get the motor running.

It also has a much longer cycle life compared to traditional deep cycle batteries, up to a whopping 400 cycles at 80 percentage depth of discharge.  You also get a high stable voltage for longer periods than you would with a conventional deep cycle battery.

And as well as getting plenty of motor power you also get all the power you need for all your on-board electronic accessories.

It recharges really quickly and efficiently too, better than any other comparable battery on the market today.  You can reach a full charge in just 4 to 6 hours.

Its dimensions are just 16.8 x 11.1 x 11.9 inches, so it’s a little bulky, and it weighs in at 77.8 pounds.

It’s an AGM battery, which is an important thing to look for in your dual-purpose marine battery - more on that in our buying guide, coming up later.

This Odyssey battery offers 40 percent more reserve capacity than the six-pack design counterparts available today, with its total reserve capacity coming in at 205 minutes, so running your onboard gadgets is no problem at all.  

It has a good solid construction, with a vibration-resistant design that protects against any high impact shock and/or mechanical vibration.  It can handle extreme temperatures too and even operate at -40 degrees centigrade.


  • 2 times the overall power of traditional marine batteries.
  • 3 times the lifespan of traditional marine batteries
  • Recharges really quickly and efficiently
  • It’s an AGM battery
  • Great reserve capacity
  • Good solid construction


  • Premium product at premium price
  • Bulky and heavy

This great little AGM dual-purpose marine battery comes from Trojan, a world leader in deep cycle battery technology.  They are known for their battery’s performance over the long-term.

It’s 12 inches long, 6.6 inches wide, and 8.1 inches high, so it’s fairly compact and weighs 64 pounds.  

This Trojan battery offers 550 cold-cranking amps, which should be more than enough for what you need to get the boat’s engine going.

And it has a really long reserve capacity to boot, this battery can run for a full 158 minutes before it will drop below the minimum voltage.  That means it can provide plenty of juice for running all the gadgets on your fishing boat

It’s an AGM battery which is just what you need (more on that in our buying guide).  And beyond that, it’s particularly well designed and there’s a reduced risk of corrosion and deterioration of parts.


  • Fairly compact
  • Plenty of cranking power
  • Long reserve capacity
  • Good long-term performance
  • AGM battery
  • Reduced risk of corrosion


  • There’s not much in the way of peer reviews on this battery as things stand at the moment, particularly on the Amazon page.

This is an excellent dual-purpose AGM marine battery from Northstar!

It falls within the pricier range of the spectrum, but for the extra cost, you get features that you just don’t get in other AGM batteries, notably the faster recharge.  The Northstar AGM charges up to 100% faster than the large majority of its competitors at the same price point.

Its dimensions are 14 x 11 x 10 inches, which is kind of big, but many powerboat users feel it’s worth it.

With 1150 cold-cranking amps, the battery always turns over quickly, and you never need to worry about getting stranded out on the water.  You can always depend on it to fire up when you need it.

It has very high reserve capacity, this battery can run for a staggering 220 minutes before dropping below the minimum voltage.  That means it can provide plenty of juice for running all the electronics you have on your fishing boat.

It’s an AGM battery, which is one thing you should really look out for (see your buying guide for more information on that).


  • Fast recharge
  • Exceptional CCA ratings
  • Very high reserve capacity
  • AGM battery


  • Premium product at a premium price
  • This battery has a relatively large physical size and weight (75 pounds), but it’s a fair trade-off for the power they offer

This is a great battery from Exide.  It may be described as a car battery but the manufacturer states that it can be used for a variety of purposes, including on fishing boats.

It offers excellent value for money and has seen some really positive customer feedback.

It also offers 760 cold-cranking amps, for all of your power-hungry electrical equipment.

Although it’s of a fair size, it’s not too heavy.  Its dimensions are Length: 278mm x Width: 175mm x Height: 190mm, and it weighs just 136 grams.

It’s an AGM battery which is always what you should be looking out for in a dual-purpose marine battery.  (More on AGM batteries in our buying guide.)

It comes complete with a 3 Years Warranty against manufacturing faults and defects.


  • Excellent value for money
  • Positive customer feedback
  • Not too heavy
  • AGM battery
  • 3-year warranty


  • Most of the customer reviews available come from people who’ve used the battery in a car rather than in a fishing boat

Best Dual Purpose Marine Batteries to Power Fishing Boats - Buyers Guide

Why AGM batteries are a good choice for a dual-purpose marine battery

Dual-purpose marine batteries are often referred to as AGM batteries, where AGM stands for absorbent glass mat.  They use a unique glass mat that’s put in place to wick the electrolyte between the battery’s plates.  

The batteries use just enough liquid to keep the glass mat moist, without allowing anything to leak out or break.  This sandwich-like construction is what makes them so stable and durable, and able to handle being charged and discharged over again and again.

AGM batteries provide high power along with a much lower internal resistance.

AGM batteries are also sealed, which makes them totally maintenance-free.  And they can stand up really well to both hot and cold temperatures.

They’re considerably better than flooded batteries.  Not only do AGM batteries have a higher cycle life than flooded batteries but they also charge up 5 times faster than them too.

Features to Look for in Dual Purpose AGM Marine Batteries


Believe it or not, 12 volts is all you need.

Marine Battery Group Size

In addition to thinking about the battery’s voltage, you should also consider it’s physical size.  You’ll need to ensure that it will in your battery tray or compartment.

You also need to consider how much the battery weighs.  That’s also a factor that can affect things.  You may decide that you need a 75-pound battery to provides the necessary power. Or alternatively, you might find a battery that is smaller but still manages to do everything you want it to.

Cold Cranking Amps (CCA)

The number of cold-cranking amps is a measure of how able the battery is to turn over the outboard engine.  The CCA rating refers to how much current (number of amps) a 12-volt battery can deliver at 0°F for 30 seconds while maintaining a voltage of at least 7.2 volts.

This represents how much power you’ve got to get the engine started.  If the CCA level is too low, you’ll struggle to get the engine going, especially if you happened to have used a lot of drawdown power throughout the course of the day.  

Basically, the size of your engine will determine how much CCA you’re going to need in your battery.

Marine Cranking Amps (MCA)

Marine Cranking Amps (MCA) is basically pretty much the same as cold-cranking amps (CCA) but measured slightly differently.  (To calculate the MCA rating of a battery compared to its CCA rating, all you have to do is multiply by 1.25.)  

The difference lies in how the two things are tested, with CCA ratings being tested at zero degrees Fahrenheit, while MCA ratings are determined at 32 degrees Fahrenheit.

Reserve Capacity

The reserve capacity of a battery is a number, given in minutes, that the battery can run before dropping below the minimum voltage.  The bigger the reserve capacity, the more current can be drawn to the additional accessories and gadgets on the vessel.


To get the best possible performance from your battery, you will need to ensure that you charge it properly.  If you charge it properly you will get a long life out of it.

You must also ensure that your charger is capable of charging a dual-purpose AGM marine battery.

AGM Only

The large majority of dual-purpose marine batteries that are out on the market today are the sealed AGM type.  You can also get lead-acid marine batteries, but these just won’t do the job, as they cannot provide the necessary cranking power, and deep cycle power draws.

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