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Lithium 12v Battery Guide -- Info needed

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I am researching this whole Lithium 12v battery versus standard 12v batteries (including AGM).

Weight savings is a no brainer but where I am stumped is the amp hours.

Lithium batteries seem to be rated the same as lead acid batteries, in amp hours, but how can a 54 amp hour lithium battery last longer than a 100 amp hour lead acid battery when you are talking in terms of loads from things like trolling motors? I know that the math gets quite complex when you are trying to figure out the run time of an electric motor on a deep cycle battery. Typically you are looking at the draw of the motor versus the amp hours of the battery.

Is it because the lead acid battery should never be discharged past 80% but a Lithium battery can be discharged all the way?

The Lithium batteries are good for 2,000 cycles which lasts a lot longer than a lead acid battery. The warranties are also much better, some are at 11 years. For the long haul the Lithium are expensive up front but pay for themselves over time. Lithium batteries are supposed to charge faster too.

For those of you with Lithium batteries, what time of run time are you getting on your trolling motor?

What information should a prespective buyer know before changing from lead acid batteries to lithium batteries?
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· I Love microskiff.com!
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Short answer is how Li batteries discharge. As the voltage drops, the current (amps) increases to maintain the load ie, TM motor speed. From peak voltage to when the BMS shuts off the battery, the voltage level stays fairly constant. In a lead acid battery, the voltage has a continuous drop until the equipment using it, the trolling motor in this discussion, can no longer operate, usually around 10.5 volts or so. If you look at a discharge chart of a lead acid battery, you'll see the discharge curve isn't linear. Since the Li batteries voltage stays relatively constant, the current draw from the load stays relatively constant, so the discharge curve is fairly flat, especially compared to the lead acid counterpart.
Amp hour calculations are just that, calculations. While they give you an idea of how long you can run a certain load on a battery, they don't give an equal comparison between the two battery types. I could be wrong so feel free to use the Google but this is how I understand it.
 

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Salt Marsh Heron 16
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I am running a 16 foot skiff with 55lb iPilot. I have a 12 Volt 65 Ah lithium battery. On a full day fishing I may run the trolling motor 2 to 4 hours at an average speed of less than 5mph, usually 2-3 mph. Sometimes bumping it up above 5 mph for short distances. My battery has never dropped below 50%. In fact it is usually around the 75% mark when I get home and push the battery level indicator on the trolling motor.
 

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Gheenoe NMZ
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Discussion Starter · #5 ·
I am running a 16 foot skiff with 55lb iPilot. I have a 12 Volt 65 Ah lithium battery. On a full day fishing I may run the trolling motor 2 to 4 hours at an average speed of less than 5mph, usually 2-3 mph. Sometimes bumping it up above 5 mph for short distances. My battery has never dropped below 50%. In fact it is usually around the 75% mark when I get home and push the battery level indicator on the trolling motor.
What brand of battery?
 

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Gheenoe NMZ
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Discussion Starter · #7 ·
Interesting. I am familiar with this company and had solar panels by them that were pretty good:

 

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Discussion Starter · #8 ·
Great information.
Change can be intimidating when you don’t know the facts. That laid out the facts well.
 
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Gheenoe NMZ
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Discussion Starter · #9 ·
Looking for advice.

I am thinking of pulling the trigger in a Lithium battery.

I am debating what I should do.

My boat is a Gheenoe NMZ with a smaller Minnkota Endura that is 40 lbs thrust.

Usually when I fish I split the time between the electric motor and a SUP Paddle. Sometimes I fish current and run the motor a bit more.

I also just moved to a new house and it had an electric motor only lake that is probably 150 acres or so.

I rarely fish an entire day but once in a while I might.
Am I okay with the Dakota 54amp hour battery or should I get the 100amp hour battery? There is a huge difference in price.

this is a very hard decision because it is a budget question too. I would rather spend less BUT I don’t want to regret not getting enough.

suggestions?
 

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Most has been said. With your sizing, look at what your gear draws at max multiplied by hours. Wind, etc. go as big as you can.
Only use a quality lithium charger. Many of the fires are a combo of cheap chargers and bms. There are some Lipo for running electronics but staying lifepo4 is smarter. You won’t have to worry about startup currents. Don’t charge in really cold weather without warming the battery (just bring it inside overnight)
Whatever battery you look at, pay attention to the specs. Try and go 60ah minimum if you can. Some of the cheaper batteries might only flow 25-30 amps continuous vs a better one discharging 50-100 continuously.
Dakota, amped, etc, you can frequently find sales if you are patient.
 

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This TM battery guide I got from Dakota is very helpful.


I ended up getting a 54ah for my 55lb TM because I found one for sale new in the box locally at a good price.
 

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Anyone else have a Dakota lithium battery? Im wanting to go lithium for my trolling motor battery and they are currently on sale. @skinny_fishing how are you liking yours? I’ve got a 55lb minn kota Ipilot and I see you’ve got something similar.
 

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Gheenoe NMZ
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Discussion Starter · #13 ·
I just bought a 100amp hour lithium with a charger by Ampere for $435 with tax and free shipping. The charger is a 10 amp charger.

may be a bit more battery than I need typically but more is better, I guess. Removes 30 or more pounds from the bow of my boat too.

Dakota lithium batteries are supposed to be really good from what I have seen.
 

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Anyone else have a Dakota lithium battery? Im wanting to go lithium for my trolling motor battery and they are currently on sale. @skinny_fishing how are you liking yours? I’ve got a 55lb minn kota Ipilot and I see you’ve got something similar.
It's working well so far, but I haven't really put it to the test yet, I wanna see how it does in the middle of the summer heated up for a half day of fishing or longer.
 
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