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Gel cell batteries are easily confused with AGM batteries. Both types of batteries are deep-cycle, spill-free, and have a low rate of discharge.

Gel batteries are a great choice for trolling motors and boats.

If you want to learn more about gel batteries ‘ unique characteristics and maintenance, you’re in the right place.

Let’s get started!

If you’re looking for a gel battery for your trolling motor, we’ve handpicked the best products depending on the size you need:

Best Gel Batteries Compared

BatteryTypeCapacityWeightTerminal
NPP NPG12-150AhGel150Ah100 lbM8
Renogy Gel 100AhGel100Ah63.9 lbM8
Weize 12V 100AhGel100Ah67 lbM6
Mighty Max ML100-12Gel100Ah68 lbM8
Mighty Max ML75-12Gel75Ah51.2 lbM6
Mighty Max ML55-12Gel55Ah38.6 lbM6
ECI Power 35AhGel35Ah23.5 lbM6
Mighty Max ML35-12Gel35Ah23 lbM6

Things You Should Know Before Buying Gel Batteries

Gel batteries are in many ways similar to flooded lead-acid batteries. The main difference is the electrolyte, which in a gel battery contains silica which gives it a gel-like composition and unique characteristics.

1. Advantages of Gel Batteries

  • They are sealed, spill-proof, and maintenance-free
  • Low self-discharge rate
  • You can discharge them down to 75% depth of discharge
  • Generally longer service life than AGM batteries
  • You can charge them up to 1000 cycles (assuming a 75% DoD)
  • They have a high degree of vibration resistance

2. Disadvantages of Gel Batteries

  • Relatively slow charging
  • Lower discharge capacity than AGM batteries
  • More expensive than flooded lead-acid batteries but much cheaper than lithium.

3. How to Charge Gel Cell Batteries?

The preferred method of charging gel batteries is to use a dedicated smart charger, and make sure its charge voltage settings are as follows:

Absorption/Bulk:14.1 – 14.4v
Float:13.5 – 13.8v
Storage:13.2 – 13.5v

Gel batteries should never be equalized, as it can damage them.

4. Know the System Voltage

The voltage of your trolling motor will determine how many 12 volt batteries you need.

A 12V trolling motor requires just one 12V battery; for 24V and 36V systems, you will need to connect 2 or 3 batteries in series. More batteries of the same size mean more capacity and more range available.

5. Select the Right Battery Size

How much run time you will get out of your battery mainly depends on two factors: battery capacity and current draw of your trolling motor.

Battery capacity is measured in Ampere-hours or Ah and current draw in amperes (amps). In theory, if your battery has 100Ah capacity and your motor draws 20 amps of current, then you can calculate its run time by dividing 100/20 = 5 hours.

However, in practical terms, you will only have 75% of the rated capacity available if you want to maintain your gel battery in good condition.

In the case of a 100Ah battery, you should only be using less than 75Ah, so your run time at the same speed will be 3.75 hours. (3 hours and 45 minutes)

6. Check Available Space and Battery Dimensions

It’s tempting to use large batteries that will give you more run time.

However, do check how much space you have available, and remember that you will need more than one marine battery if you have a 24v or 36v trolling motor.

If you have enough space but your boat is light, think about how the extra weight in the desired location could affect your boat’s balance and handling.

If you want to keep your battery in a specially designed battery box, you will need to check if the fuse is the right size for your motor.

Gel Trolling Motor Battery Reviews

1. NPP NPG12-150Ah

Made by NPPower International, this is the largest deep-cycle gel battery on our list. We recommend it for large boats, as it is very heavy at 100 pounds.

Thanks to its large Ah capacity, this gel battery can handle high current, which makes it a good match for trolling motors with high maximum Amp draw.

It comes with button style terminals (M8).

2. Renogy Gel 100Ah

Most of you will prefer a more popular 100Ah capacity, which is enough for most boats and fishing styles.

In the 100Ah category, we recommend the Renogy gel battery simply because it has such a great reputation for its marine and solar/off-grid applications.

Renogy gel batteries offer over 750 charge/discharge cycles.

They come with a 3-year warranty, although they are designed to last up to 12 years!

3. Weize 12v 100Ah

Weize 100Ah is another gel battery I don’t hesitate to recommend. They have silver-plated terminals to improve conductivity and reduce power loss.

It’s a heavy-duty battery made with industrial-grade ABS that will have no problem powering your trolling motor.

It has a maximum charge current of 20A and weighs 67 pounds.

4. Mighty Max ML100-12

Mighty Max is one of the better-known brands in the industry. They have a good reputation for long life and reliability.

They are 100% spill-proof and is shock and vibration resistant.

Mighty Max offers a full 1-year warranty and a 30-day refund policy.

5. Mighty Max ML75-12

If you need slightly smaller gel batteries, for example, to connect two in series for a 24-volt system, a 75Ah capacity gel battery might be a better choice.

Each ML75-12 battery weighs around 51 pounds.

6. ECI Power 35Ah

This is a great little gel battery for a light boat such as a kayak or a canoe.

Many small boat fishermen like them for the small factor and ease of installation.

It weighs only 23 pounds.

7. Mighty Max ML35-12

A very similar battery to ECI power, but coming from Mighty Max.

Please bear in mind 35Ah gel batteries are really only suitable for very light boats and trolling motors in 24-30-lb thrust range.

It can be installed in any position apart from upside-down.

Gel Battery FAQ

How to find out if a battery is Gel, AGM or other?

The label on your battery should clearly state “Gel” or “Gel-Filled”.

How do you maintain a gel battery?

Charge your battery as soon as possible after every use, and keep it topped up.

Never discharge your gel battery below 20% of its capacity, and do not charge it in a hot environment, with temperatures over 110°F.

How long do gel batteries last?

If properly maintained (look above), a gel cell battery can last six-seven years.

Are gel batteries better in cold weather?

No. In fact, the opposite is true – a gel battery doesn’t tolerate freezing temperatures very well.

Can a gel battery be used to start my boat’s engine?

It is not possible to use gel batteries as a starter battery because they were not designed for quick bursts of current that are necessary to start an engine. This is partly due to the resistance of the battery acid, which is higher in gel batteries.

Can I install my gel battery on its side?

Most gel battery makers allow installing them on their side. However, do check with your battery manufacturer before doing that and NEVER put it upside down.

Sources

  1. Gel BatteryScience Direct
  2. What is the difference between AGM and Gel batteriesOptima Batteries
  3. Gel vs AGM: Not Quite the Battle of the Ages, But Nice to KnowBattery Stuff
  4. Battery 101: The Pros and Cons of a Gel Mat BatteryNortheast Battery