Help in select the correct lithium battery for your trolling motor or electric outboard engine

Fluistermotor RebelcellWe get these type questions a lot: which battery do I need for my trolling motor, front troller or electric outboard engine? To answer this question you need to consider the following things. On which Voltage is the engine running? How many Amps does the engine need in use? What is de desired runtime? On this page we will help you find the right battery. It may seem difficult at the beginning, but it is actually quite simple. At the end of this page you can find the table with all different motors in combination with different Rebelcell batteries. You can always just take a quick look there to find get an idea of which battery matches your needs. On this page you can find:

If you are still not sure which battery you need for your electric outboard engine, as always feel free to contact us!

Selecting the right battery

1. On which voltage does the engine run and what is the power of the engine?

Rebelcell 24V100 Lithium accuThe voltage of the engine is nearly always clearly printed on the outside of the engine or it can be found in the user manual. If you cannot find the voltage please contact the supplier of the engine. A bit more difficult to find is the power of the engine. Most of the times you can find this in the user manual. The power of the engine is measured in Watts. At the end of this page you can find a table with some populair outboard engines and trolling motors with their voltage and their power. This can also be used as a reference if your model is not listed.

> For all 12V trolling motors you need a battery from the AV-line (the blue batteries) between 35Ah and 140Ah.

> For all 24V motors you require a 24V battery (the white batteries): the 24V50 or the 24V100.

The AV-line batteries can be used with every 12V electric outboard or trolling motor. This is due to the fact that the voltage matches the working voltage of outboard engines. At the bottom of this page we explain this in detail. When we talk about a trolling motor we mean a 12V engine. When we talk about an electric outboard engine we mean a engine that runs on 24V, 36V or 48V.

2. How much Amps does my engine draw?

This question is a bit harder to answer. Sometimes the power consumption in Amps is specified per speed / gear in the user manual. The power draw in Amps can be calculated once you know the power in Watts. This can be done by dividing the power (W) by the Voltage (V). Please note, sometimes you will know the power draw in Amps at full throttle, but not at your average  speed. Usually this is much lower.

Example: You have a 12 Volts Talamex 48LBS. Usually you run it in speed / gear 3. In the user manual you find that the power of the trolling motor in third gear is 300 Watts. At full speed (gear 5) the power is 480 Watts. The power draw in third gear is 300 / 12=25 Amps. At full throttle this is 480 / 12=40 Amps.

With Torqeedo outboard engines you can always see the power at the display. For some populair brands and models you can find the power at the bottom of this page.

3. What is the desired sailing time?

Torqeedo cruise 4.0 elektrische buitenboordThis is something you need to decide for yourself. For how many hours do you want to sail or run your engine and at what pace. Once you have figured this out you know the power draws in Amps and you can calculate which battery you need using the battery formula.

4. The battery formula

De battery formula is meant to calculate the required Amp-hours (Ah) of the battery. With a Rebelcell battery the Amp-hours are indicated in the name/type. The 12V70 AV is a 12 Volt Battery with 70Ah and the 24V100 has a capacity of 100 Amps-hours at 24 Volts. The definition of Amp-hours is quite simple: it indicated for how many hours a certain amount of Amps can be drawn. For example, a 100Ah Battery can give 1 Amp for 100 hours or 2 Amps for 50 hours or 25 Amps for 4 hours etc. The Battery formula is as follows:

Needed battery (in Ah)=Ampere (A) × desired sailing time (in hours)

Caution! The battery formula only works for lithium batteries and does not work when you use with lead batteries. With lead batteries the effective capacity is always much lower than the indicated capacity.  A 100Ah semi-traction Marine lead-acid battery offers similar runtime to a 50Ah lithium-ion battery. This has to do with the effective battery capacity.

Example 1: You have a 12Volt Minn Kota Endura Max 55LBS. On average you run your engine at 60% and you want to have a run-time of at least 4 hours. At 60% the motor draws 17 Amps. The battery formula is now: Needed battery (in Ah) = 17 (Amps drawn by the trolling motor) x 4 (the desired run time) In this case you require a battery with at least 17×4=68Ah, so the Rebelcell 12V70Ah will be the right battery for you.

Example 2: You have a Minn Kota Endura C2 30LBS and usually you run it in third gear (14A). You want to use your engine for at least 2,5 hours. In this case you will need a 12 Volt battery with 14 x 2,5=35Ah, so the 12V35Ah battery is the perfect one for you.

The battery formula can also be used if we use Watt and Watthour instead of Amps and Amp-hours The answer remains the same. On the product pages of the different Rebelcell batteries the Watthours (Wh) are specified. The battery formula in Watthours is as follows:

Needed battery (in Wh)=Watt (W) × desired sailing time (in hours)

Example 3: You have a Minn Kota Endura Max 55LBS and on average you run it at 60% of max speed and you want to have a runtime of at least 4 hours. At 60% capacity the motor has 240W power. The battery formula now is: Needed battery (in Wh) = 204 (Watts drawn by the motor) x 4 (desired runtime)

In this case you’ will need a 12 Volt battery with at least 204 x 4=816W, so the Rebelcell 12V70 AV with a capacity of 836Wh is the perfect battery for you.

More information about Voltage, Amps and Power.

Some examples

At the end of this page you can find a table with different kind of motors and the sailing time using different batteries.

Sailing time with a Minn Kota Endura Max 55 LBS with a 340cm polyester boat with 2 people
% on the throttle Volt (V) Ampere (A) Power (W) Sailing time 12V35 AV Sailing time 12V50 AV Sailing time 12V70 AV Sailing time 12V140 AV
20% 12 V 2 A 23 W 18.82 h. 26.14 h. 36.59 h. 73.18 h.
40% 12 V 7 A 80 W 5.38 h. 7.47 h. 10.45 h. 20.91 h.
60% 12 V 16 A 195 W 2.21 h. 3.07 h. 4.30 h. 8.61 h.
80% 12 V 32 A 379 W 1.14 h. 1.58 h. 2.22 h. 4.44 h.
100% 12 V 44 A 528 W 0.82 h. 1.14 h. 1.59 h. 3.18 h.
Sailing time with a Minn Kota Endura c2 30 LBS with a 230cm inflatable boat with 1 person
Gear Volt (V) Ampère (A) Power (W) Sailing time 12V35 AV Sailing time 12V50 AV Sailing time 12V70 AV Sailing time 12V140 AV
1 12 V 8 A 96 W 4.50 h. 6.25 h. 8.75 h. 17.50 h.
2 12 V 10 A 120 W 3.60 h. 5.00 h. 7.00 h. 14.00 h.
3 12 V 14 A 168 W 2.57 h. 3.57 h. 5.00 h. 10.00 h.
4 12 V 17 A 204 W 2.12 h. 2.94 h. 4.12 h. 8.24 h.
5 12 V 31 A 372 W 1.16 h. 1.61 h. 2.26 h. 4.52 h.
Sailing time with a Torqeedo Cruise 2.0 at a 480cm Polyester boat with 4 people
% of the power Volt (V) Ampère (A) Vermogen (W) Vaartijd 24V50 Vaartijd 24V100 Vaartijd 2 x 24V100
20% 24 V 17 A 400 2.94 h. 5.88 h. 11.76 h.
40% 24 V 33 A 800 1.52 h. 3.03 h. 6.06 h.
60% 24 V 50 A 1200 1.00 h. 2.00 h. 4.00 h.
80% 24 V 67 A 1600 0.75 h. 1.49 h. 2.99 h.
100% 24 V 83 A 2000 0.60 h. 1.20 h. 2.41 h.

A battery or Outdoorbox?

Once you have figured out the voltage and the requipred capacity, you will need to choose between a Battery or the Outdoorbox. In every Outdoorbox there is a battery pack with the same capacity as the corresponding battery. This means that the Outdoorbox 12.70 AV has an integrated 12V70Ah AV battery pack and an Outdoorbox 12.50 AV has a 12V50Ah AV battery pack. The choice between a battery or Outdoorbox has nothing to do with your sailing time, but with comfort, safety and ease of use.

The advantages of a Battery:

  • Cheaper to buy
  • Smaller (it takes up less space on board)

The advantages of an Outdoorbox:

  • Waterproof (IP 65)
  • Shock resistant
  • Built-in fuse
  • Easy (ANEN) connect plug for electric motor
  • 12V “cigarette plug” output with supplied USB charger
  • Hard case with handle

Choosing the right charger

Finally, you will need to choose a suitable charger for your Battery or Outdoorbox. The options vary per battery, but there are two questions you should answer for yourself:

  • Is it important that the battery charger is waterproof?
  • How fast do you want to charge your battery?

The first question is clear. If you always charge your battery indoors and keep the battery charger indoors? In that case you can opt for a “normal” battery charger. However, if you also want to be able to charge the battery on board and install the charger permanently in your boat, we recommend a waterproof charger. In addition, you often have the option between a normal charger and a fast charger. If you always drive your boat for a few hours and have the option to charge overnight for your next (fishing) trip, then a normal charger will suffice. However, if you want to drive the boat for a full day and recharge during a (lunch), a fast charger can be the solution. You can find information on the charge speed on the product pages of our chargers.

Tip! Put together a package of battery and charger (and possibly accessories) and benefit from a discount.

A Rebelcell Battery for every electric outboard

The table below shows different engines and the sailing time per battery. In practice, the sailing time may differ a bit, depending on the circumstances.
Motor Gear / % Volt (V) Ampere (A) Power (W) Runtime 12V35 AV Runtime 12V50 AV Runtime 12V70 AV Runtime 12V100 AV Runtime 12V140 AV
432 Wh 634 Wh 836 Wh 1290 Wh 1679 Wh
Minn Kota endura c2 30 Gear 1 12 V 8 A 96 W 4.50 u 6.60 u 8.71 u 13.44 u 17.49 u
Minn Kota endura c2 30 Gear 2 12 V 10 A 120 W 3.60 u 5.28 u 6.97 u 10.75 u 13.99 u
Minn Kota endura c2 30 Gear 3 12 V 14 A 168 W 2.57 u 3.77 u 4.98 u 7.68 u 9.99 u
Minn Kota endura c2 30 Gear 4 12 V 17 A 204 W 2.12 u 3.11 u 4.10 u 6.32 u 8.23 u
Minn Kota endura c2 30 Gear 5 12 V 31 A 372 W 1.16 u 1.70 u 2.25 u 3.47 u 4.51 u
Minn Kota endura c2 34 Gear 1 12 V 9 A 105 W 4.10 u 6.02 u 7.94 u 12.25 u 15.95 u
Minn Kota endura c2 34 Gear 2 12 V 11 A 132 W 3.28 u 4.82 u 6.35 u 9.80 u 12.76 u
Minn Kota endura c2 34 Gear 3 12 V 15 A 184 W 2.34 u 3.44 u 4.54 u 7.00 u 9.11 u
Minn Kota endura c2 34 Gear 4 12 V 19 A 224 W 1.93 u 2.83 u 3.74 u 5.77 u 7.50 u
Minn Kota endura c2 34 Gear 5 12 V 34 A 408 W 1.06 u 1.55 u 2.05 u 3.16 u 4.12 u
Minn Kota endura c2 40 Gear 1 12 V 10 A 118 W 3.67 u 5.39 u 7.10 u 10.96 u 14.27 u
Minn Kota endura c2 40 Gear 2 12 V 12 A 147 W 2.94 u 4.31 u 5.68 u 8.77 u 11.41 u
Minn Kota endura c2 40 Gear 3 12 V 17 A 206 W 2.10 u 3.08 u 4.06 u 6.26 u 8.15 u
Minn Kota endura c2 40 Gear 4 12 V 21 A 250 W 1.73 u 2.54 u 3.34 u 5.16 u 6.71 u
Minn Kota endura c2 40 Gear 5 12 V 38 A 456 W 0.95 u 1.39 u 1.83 u 2.83 u 3.68 u
Minn Kota endura c2 45 Gear 1 12 V 11 A 130 W 3.32 u 4.87 u 6.43 u 9.92 u 12.91 u
Minn Kota endura c2 45 Gear 2 12 V 14 A 163 W 2.66 u 3.90 u 5.14 u 7.93 u 10.33 u
Minn Kota endura c2 45 Gear 3 12 V 19 A 228 W 1.90 u 2.79 u 3.67 u 5.67 u 7.38 u
Minn Kota endura c2 45 Gear 4 12 V 23 A 276 W 1.56 u 2.29 u 3.02 u 4.67 u 6.07 u
Minn Kota endura c2 45 Gear 5 12 V 42 A 504 W 0.86 u 1.26 u 1.66 u 2.56 u 3.33 u
Minn Kota endura c2 50 Gear 1 12 V 12 A 142 W 3.03 u 4.45 u 5.87 u 9.06 u 11.79 u
Minn Kota endura c2 50 Gear 2 12 V 15 A 178 W 2.43 u 3.56 u 4.69 u 7.24 u 9.43 u
Minn Kota endura c2 50 Gear 3 12 V 21 A 249 W 1.73 u 2.54 u 3.35 u 5.17 u 6.74 u
Minn Kota endura c2 50 Gear 4 12 V 25 A 303 W 1.43 u 2.09 u 2.76 u 4.26 u 5.55 u
Minn Kota endura c2 50 Gear 5 12 V 46 A 552 W 0.78 u 1.15 u 1.51 u 2.34 u 3.04 u
Minn Kota endura c2 55 Gear 1 12 V 13 A 155 W 2.79 u 4.09 u 5.40 u 8.33 u 10.84 u
Minn Kota endura c2 55 Gear 2 12 V 16 A 194 W 2.23 u 3.28 u 4.32 u 6.67 u 8.67 u
Minn Kota endura c2 55 Gear 3 12 V 23 A 271 W 1.59 u 2.34 u 3.09 u 4.76 u 6.20 u
Minn Kota endura c2 55 Gear 4 12 V 27 A 329 W 1.31 u 1.93 u 2.54 u 3.92 u 5.10 u
Minn Kota endura c2 55 Gear 5 12 V 50 A 600 W 0.72 u 1.06 u 1.39 u 2.15 u 2.80 u
Minn Kota endura MAX 40 20% 12 V 2 A 20 W 21.79 u 31.98 u 42.17 u 65.07 u 84.69 u
Minn Kota endura MAX 40 40% 12 V 6 A 69 W 6.23 u 9.14 u 12.05 u 18.59 u 24.20 u
Minn Kota endura MAX 40 60% 12 V 14 A 169 W 2.56 u 3.76 u 4.96 u 7.65 u 9.96 u
Minn Kota endura MAX 40 80% 12 V 27 A 327 W 1.32 u 1.94 u 2.56 u 3.94 u 5.13 u
Minn Kota endura MAX 40 100% 12 V 38 A 456 W 0.95 u 1.39 u 1.83 u 2.83 u 3.68 u
Minn Kota endura MAX 45 20% 12 V 2 A 21 W 20.70 u 30.38 u 40.06 u 61.81 u 80.45 u
Minn Kota endura MAX 45 40% 12 V 6 A 73 W 5.91 u 8.68 u 11.45 u 17.66 u 22.99 u
Minn Kota endura MAX 45 60% 12 V 15 A 177 W 2.44 u 3.57 u 4.71 u 7.27 u 9.46 u
Minn Kota endura MAX 45 80% 12 V 29 A 344 W 1.25 u 1.84 u 2.43 u 3.75 u 4.88 u
Minn Kota endura MAX 45 100% 12 V 40 A 480 W 0.90 u 1.32 u 1.74 u 2.69 u 3.50 u
Minn Kota endura MAX 50 20% 12 V 2 A 23 W 18.82 u 27.62 u 36.42 u 56.19 u 73.14 u
Minn Kota endura MAX 50 40% 12 V 7 A 80 W 5.38 u 7.89 u 10.40 u 16.06 u 20.90 u
Minn Kota endura MAX 50 60% 12 V 16 A 195 W 2.21 u 3.25 u 4.28 u 6.61 u 8.60 u
Minn Kota endura MAX 50 80% 12 V 32 A 379 W 1.14 u 1.67 u 2.21 u 3.41 u 4.43 u
Minn Kota endura MAX 50 100% 12 V 44 A 528 W 0.82 u 1.20 u 1.58 u 2.44 u 3.18 u
Minn Kota endura MAX 55 20% 12 V 2 A 24 W 18.00 u 26.42 u 34.83 u 53.75 u 69.96 u
Minn Kota endura MAX 55 40% 12 V 7 A 84 W 5.14 u 7.55 u 9.95 u 15.36 u 19.99 u
Minn Kota endura MAX 55 60% 12 V 17 A 204 W 2.12 u 3.11 u 4.10 u 6.32 u 8.23 u
Minn Kota endura MAX 55 80% 12 V 33 A 396 W 1.09 u 1.60 u 2.11 u 3.26 u 4.24 u
Minn Kota endura MAX 55 100% 12 V 46 A 552 W 0.78 u 1.15 u 1.51 u 2.34 u 3.04 u
Talamex tm 30 Gear 1 12 V 4 A 48 W 9.00 u 13.21 u 17.42 u 26.88 u 34.98 u
Talamex tm 30 Gear 2 12 V 9 A 108 W 4.00 u 5.87 u 7.74 u 11.94 u 15.55 u
Talamex tm 30 Gear 3 12 V 14 A 168 W 2.57 u 3.77 u 4.98 u 7.68 u 9.99 u
Talamex tm 30 Gear 4 12 V 19 A 228 W 1.89 u 2.78 u 3.67 u 5.66 u 7.36 u
Talamex tm 30 Gear 5 12 V 24 A 288 W 1.50 u 2.20 u 2.90 u 4.48 u 5.83 u
Talamex tm 40 Gear 1 12 V 6 A 72 W 6.00 u 8.81 u 11.61 u 17.92 u 23.32 u
Talamex tm 40 Gear 2 12 V 13 A 156 W 2.77 u 4.06 u 5.36 u 8.27 u 10.76 u
Talamex tm 40 Gear 3 12 V 20 A 240 W 1.80 u 2.64 u 3.48 u 5.38 u 7.00 u
Talamex tm 40 Gear 4 12 V 26 A 312 W 1.38 u 2.03 u 2.68 u 4.13 u 5.38 u
Talamex tm 40 Gear 5 12 V 34 A 408 W 1.06 u 1.55 u 2.05 u 3.16 u 4.12 u
Talamex tm 48 Gear 1 12 V 8 A 96 W 4.50 u 6.60 u 8.71 u 13.44 u 17.49 u
Talamex tm 48 Gear 2 12 V 16 A 192 W 2.25 u 3.30 u 4.35 u 6.72 u 8.74 u
Talamex tm 48 Gear 3 12 V 25 A 300 W 1.44 u 2.11 u 2.79 u 4.30 u 5.60 u
Talamex tm 48 Gear 4 12 V 32 A 384 W 1.13 u 1.65 u 2.18 u 3.36 u 4.37 u
Talamex tm 48 Gear 5 12 V 40 A 480 W 0.90 u 1.32 u 1.74 u 2.69 u 3.50 u
Talamex tm 58 Gear 1 12 V 10 A 120 W 3.60 u 5.28 u 6.97 u 10.75 u 13.99 u
Talamex tm 58 Gear 2 12 V 19 A 228 W 1.89 u 2.78 u 3.67 u 5.66 u 7.36 u
Talamex tm 58 Gear 3 12 V 30 A 360 W 1.20 u 1.76 u 2.32 u 3.58 u 4.66 u
Talamex tm 58 Gear 4 12 V 41 A 492 W 0.88 u 1.29 u 1.70 u 2.62 u 3.41 u
Talamex tm 58 Gear 5 12 V 51 A 612 W 0.71 u 1.04 u 1.37 u 2.11 u 2.74 u
Haswing Osapian 55 Gear 1 12 V 11 A 132 W 3.27 u 4.80 u 6.33 u 9.77 u 12.72 u
Haswing Osapian 55 Gear 2 12 V 13 A 156 W 2.77 u 4.06 u 5.36 u 8.27 u 10.76 u
Haswing Osapian 55 Gear 3 12 V 21 A 252 W 1.71 u 2.52 u 3.32 u 5.12 u 6.66 u
Haswing Osapian 55 Gear 4 12 V 24 A 288 W 1.50 u 2.20 u 2.90 u 4.48 u 5.83 u
Haswing Osapian 55 Gear 5 12 V 43 A 516 W 0.84 u 1.23 u 1.62 u 2.50 u 3.25 u

Can I use a Lithium battery without any problems with my trolling motor or electric outboard?

Yes, Rebelcell batteries are safe to use. The user manual of your outboard engine may state that the motor is not suitable for use of lithium batteries. This is because certain lithium batteries have a higher voltage than lead batteries. Rebelcell has developed AV batteries for this reason. AV stands for adjusted voltage. Instead of a peak voltage of 16.8V (peak voltage is the voltage of the battery when it is fully charged), these batteries have a peak voltage of 12.6V so nearly identical to that of a lead battery. So you can safely use a Rebelcell AV battery with any brand of electric motor. More information about the voltage of batteries is given here.

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