Fish finders need power to run, and most anglers pair these powerful electronics with other juice-hungry options like trolling motors and live wells. When all’s said and done, that means you need a long-running, deep-discharging, fast-recharging battery to keep everything running as it should.

On larger boats running big trolling motors, two or three 12V, deep-cycle batteries are the norm, and weight isn’t much of an issue. But on inflatables, jon boats, kayaks, and canoes, space and capacity are at a premium, and small, light batteries are a necessity.

If you need a durable, reliable battery to power your fishing electronics but don’t know where to start, we’ve got you covered. Below, we’ll review some of the batteries to power your fishing electronics, as well as provide a complete buying guide to get you up to speed quickly.

Quick glance at the best batteries for fishing electronics:

Table of Contents (clickable)

Best Batteries For Fishing Electronics Reviewed

Dakota Lithium 12V 100Ah Deep Cycle – Best Premium Battery

Dakota Lithium | 12V 100Ah LiFePO4 | 11 Year USA Warranty 2000+ Deep Cycle Battery | Charger Included

Amazon 

Type: LiFePO4
RC: ?
Weight: 31.9 lbs.
Size:12.99 x 6.77 x 8.66

Dakota Lithium makes use of the latest battery tech: cool-running Lithium iron phosphate. While not quite as feather weight as Lithium-ion competitors, lithium-metal batteries deliver more stable long-term performance, generate less heat, are less toxic, and cost less.

That adds up to an attractive package for anglers who crave low-weight, high-performance batteries.

Dakota Lithium doesn’t report RC numbers, but the 100 amp hours this 12V delivers put it in direct competition with the awesome VMAX MR127 in terms of run time. It will deliver power you can depend on all day, every day, and because this tech is truly cutting-edge, you’ll also get fast recharging and ridiculous cycle life – about 4 times longer cycling!

That helps to explain the high cost of these batteries, as they’ll simply last and last and last, meaning that per-use costs are much lower than traditional battery tech.

This 12V isn’t as small as a similar lithium-ion battery, and the Group Size isn’t provided by Dakota Lithium. But at just 31.9 pounds, it’s cutting weight considerably, offering an incredible power-to-weight ratio and making this an excellent choice for anglers who need plenty of juice for a trolling motor and fish finder but who can’t afford the weight of an AGM.

Lighter, longer lasting, and just as powerful? That sounds too good to be true! But with Dakota, they deliver exactly that!

That excellent performance comes at a price, and this is the most expensive battery on our shortlist. But with all the advantages this brand delivers with their products, we believe it’s absolutely worth the cost.

Pros:

  • Awesome cycle life
  • Fast recharging
  • Deep discharge
  • Long-running time
  • Light!

Cons:

  • Expensive!

Dakota Lithium 12V 10Ah Deep Cycle – Smallest, Lightest Fish Finder Battery

Dakota Lithium | 12V 10Ah LiFePO4 | 11 Year USA Warranty 2000+ Deep Cycle Battery

Amazon 

Type: LiFePO4
RC: ?
Weight: 2.75 lbs.
Size: 5.94 x 2.55 x 3.78

Finally, for anglers who want a dedicated fish finder battery, Dakota Lithium’s 12V 10Ah deep cycle is simply perfect. That’s not something we say often, so pay attention!

Offering plenty of power to run your fishing electronics for days, you can count on this battery to deliver the goods in all conditions.

And at just under 6 inches in its longest dimension, finding space for the 10Ah deep cycle is easy, no matter how cramped your boat is.

And the awesome news? This little guy weighs in at just 2.75 pounds!

For small boat and kayak anglers who need ultra-long run times for fishing electronics, look no further.

Pros:

  • Awesome cycle life
  • Fast recharging
  • Deep discharge
  • Long running time
  • Small!
  • Ultra-light!

Cons:

  • Can’t run a trolling motor

Dakota Lithium 12V 54Ah Deep Cycle

Dakota Lithium | 12V 54Ah LiFePO4 | 11 Year USA Warranty 2000+ Deep Cycle Battery | Charger Included

Amazon 

Type: LiFePO4
RC: ?
Weight: 17.6 lbs.
Size: 9.01 x 5.43 x 8.38 

For small boats where weight is a big issue, like kayaks running a trolling motor and fish finder, Dakota Lithium’s 12V 54Ah Deep Cycle is a very smart pick.

Basically just a sized-down version of the excellent 100Ah battery we reviewed above, you can expect long run times and fast recharging from this battery. With smaller trolling motors and light boats, run times will be awesome, and from small dimension to a weight any kayaker can live with, there’s nothing not to like about this battery.

Pros:

  • Awesome cycle life
  • Fast recharging
  • Deep discharge
  • Long running time
  • Light!

Cons:

  • Expensive!

VMAX MR127 AGM Deep Cycle – Best Budget Battery

VMAX MR127 12 Volt 100Ah AGM Deep Cycle Maintenance Free Battery Compatible with Boats and 40-100lb, minnkota, Cobra, sevylor and Other trolling Motor (Group 27 Marine Deep Cycle AGM Battery)

Amazon 

Type: AGM
RC: 200 minutes
Weight: 68 lbs.
Size: Group 27; 6.75 x 12.1 x 8.2 (8.46 with terminals)

The venerable VMAX MR127 is among the most popular batteries you’ll find on the water, having proven itself season after season. Priced right, it delivers long battery life for anglers who run a trolling motor, live well, and fish-finding electronics.

Delivering a full 200 minutes of RC and tolerating deep discharges season after season, you can count on the VMAX MR127 to provide reliable performance – even when you’re tough on your boat and fishing in extreme heat.

It’s durable, tough as nails, and ready to work.

That power comes at a price, however, and this Group 27 battery weighs in at a massive 68 pounds.

For anglers in small boats, this weight-to-performance ratio may not be ideal, but if you’re running a typical bass boat or center console, the VMAX MR127 is among your best options.

Pros:

  • Dependable 
  • Awesome RC
  • Tolerates deep discharges, season after season

Cons:

Interstate Batteries SRM-27

Type: Wet-cell
RC: 160 minutes
Weight: 50.3 lbs.
Size: Group 27; 6.75 x 12.75 x 9.5

Batteries get expensive quickly, and not everyone can drop hundreds of dollars on each battery needed to run a boat’s electronics. For anglers who need excellent performance that won’t break the bank, Interstate Batteries’ SRM-27 is hard to beat.

Relying on old-school, wet-cell tech, these batteries nonetheless deliver 160 minutes of RC, offering plenty of power for trolling motors, live wells, and fish finders. 

They’ve proven themselves to be a dependable choice for decades now, and with minimal maintenance of their acid-water levels, you get long run times and dependable service lives.

Of course, wet cells demand a bit more time on the recharger than more modern battery designs, but they’re awfully budget-friendly.

The SRM-27, as its name suggests, is a Group 27 battery. It weighs in at a hefty 50.3 pounds, delivering a very nice weight-to-performance ratio for boats that need plenty of power.

Pros:

  • Dependable
  • Good RC
  • Inexpensive!

Cons:

  • Old-school tech that takes more maintenance
  • Longer recharge times than modern battery tech

Interstate Batteries SRM-31

Type: Wet-cell
RC: 210 minutes
Weight: 59.7 lbs.
Size: Group 31; 6.69 x 13 x 9.63

When you need power to spare and ultra-long run times, Interstate Batteries SRM-31 is a strong choice.

This wet-cell power source offers 210 minutes of RC. For anglers who plan to run a trolling motor at higher speeds, use point-locking systems in heavier currents or wind, or run multiple electronics constantly, the SRM-31 really shines.

This beast has proven its reliability in the real world, and if you’re willing to check its water levels carefully and treat it right, it will deliver power to spare, year after year.

As you’d expect, that power demands a trade-off. Anticipate larger dimensions and a hefty 59.7 pounds. That’s still lighter than the VMAX MR127, making this an excellent choice for boats that need 36V systems but need to keep costs and weight in check.

Pros:

  • Dependable
  • Great RC
  • Inexpensive!

Cons:

  • Old-school tech that takes more maintenance
  • Longer recharge times than modern battery tech

How To Pick the Right Fish Finder Battery for Your Needs

If you think that all batteries are pretty much alike, you couldn’t be more wrong.

Batteries are designed for distinct purposes, and using the wrong battery type just won’t get the job done.

Three battery types are common on the water: starting batteries, deep cycle batteries, and dual use batteries.

It’s absolutely essential that you understand which battery you need!

Battery Types: Know the Difference!

Starting batteries

Starting batteries have thin, spongy with lots of surface area exposed to the catalyst. This creates a powerful, short burst of electricity that’s perfect for starting an outboard.

Starting batteries demand constant recharging through an alternator, as you probably know if you’ve ever had yours fail. Without that constant tickle, they quickly discharge.

Note: Starting batteries will not run fishing electronics or trolling motors for very long, and deep discharges damage the battery.

Deep cycle batteries

Deep cycle Batteries sport thick, massive plates that can store huge amounts of power. They’re very good at delivering constant, low-level voltage over a long time, and they tolerate deep discharge and recharging cycles really well.

That’s why they’re called “deep cycle;” they can take repeated deep discharges (20 percent of maximum) without damage or reduction in efficiency.

These are dedicated fishing electronics and trolling motor batteries, and they’re what you’re looking for.

Dual-use batteries

Dual-use batteries are a compromise between a starting and a deep cycle battery. Their plates offer enough surface area exposed to the catalyst to deliver an engine-starting burst of power, but they’re also thick enough to deliver reliable electricity to your trolling motor.

They’re not ideal for running trolling motors because they lack the long RCs of a true deep cycle battery, and taking them below about 50 percent of their maximum charge will affect battery life.

Intended for anglers who need one battery to do it all, these are not the best choice for your electronics.

Battery Tech: Wet-Cell vs. SLA/VRLA/AGM vs. Lithium-Ion vs. Lithium Lead Phosphate

Battery tech is advancing quickly, and the power sources you grew up with are old news now.

You need to understand these tech options to make the right choice for your needs and budget.

Wet-Cell Batteries

Wet-cell batteries have remained pretty much unchanged since their introduction in the late 19th century. Their low price point has kept them popular, and if cared for, they can survive quite a few charging cycles. They’re also resistant to damage from overcharging and weigh less than typical SLA or AGM alternatives.

Wet-cell batteries need a bit of maintenance, and you’ll need to keep their water level topped up to keep them working well. Of course, battery acid is highly corrosive, so you’ll want to use proper eye protection and keep the acid where it belongs.

Sealed Lead-Acid (SLA), Valve-Regulated Lead-Acid (VRLA), and Absorbed Glass Mat (AGM)

Essentially three  terms for the same chemical system, SLA/VRLA batteries use lead plates and acid as their basic components. AGM batteries add one additional chemical trick. The result of this tech is that they’re all heavy and safe – and that they don’t require the maintenance of traditional wet cell batteries.

These batteries hold a charge well, but they are quite a bit more expensive than typical wet-cell alternatives, and they can be damaged by overcharging.

Lithium-Ion (Li-ion) and Lithium Lead Phosphate (LiFePO4)

These power sources switch the lead and acid of traditional tech for carbon and lithium salts in Li-ion batteries or lead phosphate and lithium salts in LiFePO4 batteries. This allows them to be much smaller and lighter than equally powerful SLA or AGM batteries.

They also tolerate deep discharges better than AGM batteries, recharge faster, and have much longer cycle life, meaning that you can discharge and recharge them any more times over their service life.

That typically brings per use costs down far below AGM or wet-cell batteries.

That said, most trolling motor manufacturers insist that they deliver a higher voltage than they’re stated rating, meaning that a lithium 12v may deliver 14 to 16 volts of power.

Minn Kota has this to say: “Minn Kota trolling motors can run on Lithium Ion batteries. However, they are specifically designed to run on traditional lead acid batteries (flooded, AGM or GEL). Lithium Ion batteries maintain higher voltages for longer periods of time than lead acid. Therefore, running a Minn Kota trolling motor at speeds higher than 85% for a prolonged period could cause permanent damage to the motor.”

And Newport Vessels shares this concern. “Similar to all other trolling motor brands, we also advise against using lithium batteries with our products. Lithium batteries tend to run at a higher voltage for longer durations (14-16V) than Lead-Acid batteries (13V). Trolling motors are designed to be used with batteries that output around 13V at most and then primarily 12V. Using a higher voltage can put wear and tear on the motor and potentially damage some of the internal components and ruin your motor.”

The lithium battery on our list uses lithium iron phosphate (LiFePO4), which Minn Kota accepts as a viable power source. “The LiFePO4 Lithium batteries can be used with our motor. LiFePO4 batteries that have a maximum continuous output current ratings need to be higher than the maximum current ratings of the trolling motor or the battery will turn off.”

If you choose a lithium iron phosphate battery for your fishing electronics, it will work perfectly.

What We Consider When Selecting a Battery for Fishing Electronics

Reserve Capacity

As Simon Slayford of Hunker explains, “Reserve capacity is defined as the number of minutes a fully charged 12-volt battery at 80 degrees Fahrenheit can provide 25 amperes at 10.5 volts until the voltage decreases.” That definition can be hard to wrap your head around, so let’s keep it simple: reserve capacity is just a measure of how long a battery can supply constant, continuous power at 80F.

Lots of people say that RC is “just a number.” There’s some truth to that. A battery’s RC rating can’t tell you how long it will run your fish finder, live well, and trolling motor as there are too many variables beyond that number: temperature, draw, how well you’ve performed basic battery maintenance, etc. 

But all other things being equal, higher RC numbers mean longer run times for your trolling motor.

Look for batteries with the highest RCs you can afford, but recognize the trade-off of weight and size as you step up in RC. Larger, heavier batteries will typically provide more power over time, but their size and weight can quickly become an issue on a ‘yak.

Durability

Heat and vibration are the enemies of battery performance, and a good trolling motor battery is going to be built tough as nails to resist both.

The batteries on our list are proven performers that can take the summer sun and the jostling of waves on your kayak. And in my experience, kayaks just don’t put batteries through the pounding that a bass boat does, so there’s less to worry about there.

Price to Performance Ratio

You typically get the performance you pay for, and that’s as true for batteries as it is for anything else.

Higher prices buy you longer RC times, as well as smaller, lighter batteries.

For a kayak trolling motor, maximum RC may not be critical, but size and weight are real worries.

I recommend that you buy the smallest, lightest battery you can afford that provides enough power for you to run your electronics and trolling motor at the throttle settings and for the durations that you commonly demand.

Maintenance Issues

All batteries demand reasonable maintenance:

  • Charge your battery after each use
  • Never discharge your battery fully
  • Use a multi-stage charger to provide the right voltage at the right time
  • Store your batteries in cool, but not ice-cold temperatures
  • Never store an uncharged battery
  • Keep the terminals clean

Weight vs. Performance

Bass boats don’t need to worry too much about battery weight, but even there, a big bank of heavy batteries can become a problem.

On a kayak, where both capacity and space are at a premium, a big, heavy battery just might not be an option.

Typically, a larger, heavier battery can generate more power over time as more massive plates simply provide more capacity to generate electricity. But on a kayak, loading 60 pounds into the bow or stern can have tremendous effects on trim and handling, and you may find that the most powerful battery you can afford just won’t work well with your ‘yak.

Instead, pay close attention to weight and size when comparing performance. A smaller, lighter battery may not hold as much juice, but it might just be the best option for you.

Size and Placement

Before you pull the trigger on a trolling motor battery for your boat give some careful thought to where you plan to place it.

You’ll need enough space for the battery and cables long enough to reach the motor.

Don’t guess – measure!

And measure carefully – a battery that doesn’t fit won’t do you any good. But don’t just measure the space for the body of the battery: take the terminals into account, too!

Batteries come in multiple sizes called “groups,” though dimensions can vary. 

In practice, batteries within a given group will have slightly different dimensions, so never assume.

Final Thoughts

The best battery for your fishing electronics depends on too many factors for us to call a clear winner, and anglers fishing from a kayak without a trolling motor need something very different from fishermen using a center console with a live well, fish finder, and 36V trolling motor.

If weight and space are at a premium, and you’re only running a fish finder, it’s impossible to beat Dakota Lithium’s 12V 10Ah Deep Cycle. Small, super light, and packed with power, it’ll keep even the greediest electronics running for days.

But if you run a typical bass boat, where a trolling motor and live well will be added to the mix, and you need tons of run time for a powerful 36V, reach for Dakota Lithium’s 12V 100Ah Deep Cycle. Yes, these are going to set you back a bit, and your wallet will definitely feel the impact if you need to buy three of these, but the performance-to-weight ratio, super long cycle life, and quick recharging are well worth it.

Finally, if you need a budget option that delivers reliably long run times, VMAX’s MR127 AGM Deep Cycle is a time-tested, real-world proven performer that offers very long run times.

Whichever of these you pick, you’ll be happy you did.

As always, we’re here to answer any questions you might have, so please leave a comment below.

Source: usangler.com