• Post author:
  • Post last modified:September 19, 2022
We thoroughly research all products to give you unbiased recommendations. Learn more about our review process.

Properly charging your trolling motor battery is essential to extending the battery’s life and ensuring your motor’s peak performance.

There are two types of batteries commonly used in trolling motors: lead acid batteries and lithium-ion batteries. The type of battery used and its voltage determine the right kind of charger you should get.

In this article, we’ll review the best trolling motor battery chargers for different battery setups and uses. We’ll also give you tips to help you select the right one for your needs.

Let’s get started.

Comparison: Best Trolling Motor Battery Chargers

Best Portable Charger

NOCO Genius10

  • Smart and portable 1-bank charger
  • 10A charging current
  • Lead-acid and lithium compatible
Best 2-Bank Charger

NOCO Genius GEN5X2

  • Smart/automatic 2-bank charger
  • 5A charging current per battery (10A total)
  • Lead-acid and lithium compatible
Best 3-Bank Charger

NOCO Genius GEN5X3

  • Smart/automatic 3-bank charger
  • 5A charging current per battery (15A total)
  • Lead-acid and lithium compatible
Best 4-Bank Charger

NOCO Genius GENPRO10X4

  • Smart/automatic 4-bank charger
  • 10A charging current per battery (40A total)
  • Lead-acid and lithium compatible
Fast 4 Bank Charger

Minn Kota Precision

  • 2-bank or 4-bank smart charger
  • 6, 10 or 15A (fast) charging current per battery
  • Flooded, gel, AGM-compatible (no lithium)
Best DC-DC Charger

Minn Kota Alternator Charger

  • 1, 2, or 3 bank charging with engine alternator on the fly
  • 10A per battery charging current
  • Flooded and AGM-compatible (no lithium)

Trolling Motor Battery Charger Reviews




NOCO Genius10

BEST PORTABLE BATTERY CHARGER FOR TROLLING MOTORS

SPECIFICATIONS

Type: Portable   Current Rating: 10A   Battery Types: Flooded, Gel, AGM, SLA, VRLA, Lithium/LiFePO4   Max Battery Capacity: 230 Ah   Input Voltage: 120 Volts   Dimensions: 2.4 x 3.7 x 8.2 inches   Weight: 3 lb

BEST DEALS

PROS

  • Fully automatic and portable (with battery clamps)
  • Charges all major battery types, including lithium
  • Temperature compensation prevents overcharging
  • Repair mode and desulfation
  • Possible to charge near-dead batteries

CONS

  • Only one battery charging at a time
  • Not fully waterproof (no IP68)

NOCO Genius10 is a fully automatic (smart) charger that will take care of virtually any type of battery.

This model comes with alligator clips so that you can easily connect and disconnect it from the battery.

The NOCO chargers are straightforward to use. You have different charging options depending on how long you press the “Mode” button.

Once the battery is fully charged it will go to maintenance mode. That means you can connect the charger to the battery and forget about it. When you return, it will be fully charged and ready to use.




NOCO Genius GEN5X2

BEST 2 BANK ONBOARD BATTERY CHARGER

SPECIFICATIONS

Type: Onboard   Current Rating: 10A (5A per battery)   Battery Types: Flooded, Gel, AGM, SLA, VRLA, Lithium/LiFePO4   Max Battery Capacity: 2 x 120 Ah   Input Voltage: 120-240 Volts   Dimensions: 2.2 x 5.6 x 7.0 inches   Weight: 5.3 lb

BEST DEALS

PROS

  • Charges up to 2 x 120Ah batteries
  • Charges all major battery types, including lithium
  • Temperature compensation prevents overcharging
  • Automatic sulfation detection and repair
  • Possible to charge near-dead batteries
  • Fully sealed/waterproof (IP68 rating)

CONS

  • A little bulky

NOCO Genius GEN5X2 is an excellent smart charger designed for onboard use.

It is compatible with all popular battery chemistries, including flooded lead acid, gel and AGM. It can also charge lithium batteries.

The charging current is 5A per battery, 10A in total, which is enough to charge batteries up to 120Ah capacity.

The Genius GEN5X2 is fully waterproof and rugged to withstand the marine environment.




NOCO Genius GEN5X3

BEST 3 BANK ONBOARD BATTERY CHARGER

SPECIFICATIONS

Type: Onboard   Current Rating: 15A (5A per battery)   Battery Types: Flooded, Gel, AGM, SLA, VRLA, Lithium/LiFePO4   Max Battery Capacity: 3 x 120 Ah   Input Voltage: 120-240 Volts   Dimensions: 2.2 x 6.5 x 7.9 inches   Weight: 6.1 lb

BEST DEALS

PROS

  • Charges up to 3 x 120Ah batteries
  • Fully sealed/waterproof (IP68 rating)
  • Charges flooded, gel, AGM and lithium batteries
  • Temperature compensation prevents overcharging
  • Automatic sulfation detection and repair
  • Possible to charge near-dead batteries

CONS

  • The user’s manual is not entirely clear

NOCO Genius GEN5X3 is in many ways very similar to the GEN5x2 model.

The main difference is the capability to charge three 12-volt batteries (3-bank). It’s also larger and heavier, as expected.

If you have 3 batteries on board and are not planning on adding more in the future, this charger will keep them topped up.

Our only complaint is the lack of clear instructions in the manual. It’s not obvious how to select different charging modes.




NOCO Genius GENPRO10X4

BEST 4 BANK ONBOARD BATTERY CHARGER

SPECIFICATIONS

Type: Onboard   Current Rating: 40A (10A per battery)   Battery Types: Flooded, Gel, AGM, SLA, VRLA, Lithium/LiFePO4   Max Battery Capacity: 4 x 230 Ah   Input Voltage: 120-240 Volts   Dimensions: 2.8 x 9.1 x 11.4 inches   Weight: 15.5 lb

BEST DEALS

PROS

  • Smart/automatic 4-bank charger
  • 10A charging current per battery (40A total)
  • Charges up to 4 x 230Ah batteries
  • AGM, gel, flooded lead-acid and lithium/LiFePO4 compatible
  • Temperature compensation prevents overcharging
  • Automatic sulfation detection and repair
  • Fully sealed, waterproof (IP68)

CONS

  • Large & expensive

NOCO Genius GENPRO10X4 is the best 4-bank battery charger available today.

If you have four 12-volt batteries on board, this smart charger will keep them fully charged regardless of battery type or size.

It is compatible with all popular battery chemistries, including AGM, gel, lead-acid, and lithium. Because of its high current output, 10A per battery, it will charge even the largest deep-cycle batteries (up to 230Ah).

If you have a large lithium battery bank or mixed batteries in your setup, this GENPRO10X4 is worth considering.

Word of advice: it is large at 2.8 x 9.1 x 11.4 inches, so do make sure you have available space.




Minn Kota Precision Charger

FASTEST 4 BANK ONBOARD BATTERY CHARGER

SPECIFICATIONS

Type: Onboard   Current Rating: 6, 10 or 15A per battery   Battery Types: Flooded, Gel, AGM   Input Voltage: 120 Volts   Weight: 8-17.5 lb (model-dependent)

BEST DEALS

PROS

  • 15A model is the fastest charger available
  • Charges AGM, gel and flooded lead-acid batteries
  • Multi-stage charging
  • Automatic temperature compensation
  • Corrosion protection

CONS

  • It won’t charge lithium batteries
  • Expensive

The Precision is the best onboard charger offered by Minn Kota.

There is a 2-bank and 4-bank version, as well as multiple charging current options: 6, 10 or 15A per battery.

The 15A provides a total of 60A charging current, which means the fastest charging times of any charger on our list.

Unfortunately, it still won’t charge lithium batteries.




Minn Kota Alternator Charger

BEST ALTERNATOR BATTERY CHARGER

SPECIFICATIONS

Type: Onboard   Current Rating: 10A per battery   Battery Types: Flooded, AGM   Input Voltage: 120 Volts   Weight: 5-8.5 lb (model-dependent)

BEST DEALS

PROS

  • Recharging your battery bank with engine alternator
  • 1, 2 or 3-bank model to choose from
  • Flooded, and GMS

CONS

  • It won’t charge lithium batteries

The Minn Kota Alternator Charger comes in three different models:

  • MK 1DC: 1-bank with 10A charging current
  • MK 2DC: 2-bank with 20A total charging current (10A per battery)
  • MK 3DC: 3-bank with 30A total charging current (10A per battery)

The total maximum charging current also depends on the output of your alternator.

It is not compatible with lithium batteries.

What Are Smart/Automatic Battery Chargers?

These are multi-stage, intelligent chargers, which means they monitor your battery’s current state and charge it only when necessary.

You can connect your smart charger to the battery and forget about the charging process. Your battery will be fully charged and properly maintained.

Even if left connected for a very long time, there is no risk of overcharging your battery.

By keeping the battery fully charged, smart chargers help prevent sulfation, which occurs when a battery is left partially charged for a longer time.

Things to Consider When Choosing a Battery Charger

Battery Type

First, you need to make sure that your charger will charge the battery you have. Most trolling motors are used with the following types of batteries:

If you want to use a gel or lithium-ion battery, you must ensure that your battery charger (and trolling motor) is compatible.

Our recommendation is to get a lithium-compatible charger, even if you don’t have a lithium battery yet. They are fast becoming very popular, thanks to their advantages, and chances are you’ll be getting them in the future.

Number of Batteries

Depending on the voltage of your trolling motor, you will need to charge one or more batteries. A single battery bank charger can charge a 12-Volt battery, which is all you need if you have a 12-Volt trolling motor.

If your motor operates at 24 Volts, you will need to charge two 12 Volt batteries connected in series (double bank), at 36 Volts – three batteries (triple bank), and at 48 Volts – four (quadruple bank).

Many chargers are designed to charge multiple battery banks.

Onboard vs Portable vs DC Chargers

Onboard chargers are installed and wired permanently to the batteries. This makes them very convenient to operate as all you need to do connect them to AC power.

Portable chargers need to be connected and removed from the batteries every time you need to charge them.

Alternator/DC chargers don’t require AC power. They connect to the outboard motor’s alternator and charge the batteries whenever the motor is running. The problem with this solution is that alternators often don’t generate enough current or don’t run long enough to recharge a battery fully.

Charging Current

Battery chargers come with amperage ratings that tell you how fast they can recharge depleted batteries.

The higher the Amp rating, the faster your battery will be fully charged.

Less expensive 5 Amp chargers can recharge a medium-size battery in less than 12 hours. However, if you have a large battery bank or want faster charging times, you will be much happier with a 10 Amp or 15 Amp charger.

Features

If you plan to charge your battery bank onboard or outdoors, you will need a waterproof battery charger.

Additionally, some chargers are designed to be used around salt water and come with a special corrosion-resistant coating.

Other important features to look for in a good charger are a short circuit and reverse polarity protection.

Conclusion

The best battery charger for you will depend on the type of battery you have, the number of batteries you need to charge, and your personal preferences.

If you want a simple and affordable solution, go with a standard/manual charger. If you want something more sophisticated and user-friendly, choose a smart/automatic charger.

Make sure that your charger is compatible with the battery you have and that it has the right charging current for the battery type and capacity.

And finally, look for features like waterproofing, salt water compatibility, and short circuit protection.

Happy boating!

FAQ

Do lithium trolling motor batteries need a special charger?

Yes, lithium batteries require a special charger that is compatible with their chemistry. You cannot use a lead acid charger on a lithium battery.

Do marine batteries need a special charger?

No, marine batteries can be charged with a regular battery charger. However, if you will be charging your battery onboard or in a marine environment, it is a good idea to get a waterproof or salt water resistant charger.

What is the difference between a DC and AC charger?

A DC charger connects to the outboard motor’s alternator and charges the batteries whenever the motor is running. An AC charger needs to be connected to AC power.

Can you overcharge a trolling motor battery?

Yes, you can overcharge a trolling motor battery if you use a charger with too high of an amperage rating. Always follow the battery manufacturer’s recommendations for charging rates.

What is the best way to charge a trolling motor battery?

The best way to charge a trolling motor battery is with a smart/automatic charger that is matched to the type and size of your battery bank.

Sources

NOCO

Minn Kota