Quinte Fishing

What are the advantages of running 2 batteries in parallel to just running 1 battery at a time with a second battery backup? I understand that you will get longer running time, but if you get 2 days off 2 batteries in parallel, or 1 day each off 2 batteries on a single battery hookup, is it not still the same in the end?? If you just run 1 battery at a time, at least you still have the second battery as backup. Running them in parallel you will end up with 2 dead batteries at the same time.
I've considered running 2 batteries in parallel, but don't really see any advantages. Am I missing something here??

Thanks for any input

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There's something wrong with that rod.
It has a bend in it!!!

Just my opinion, but I believe that the battery's in parallel will last longer. Each battery will provide 1/2 the draw, causing half the internal heat, which means lower resistance. I think that a battery will output more energy (total) at a low draw, that more energy is regenerated as the battery is discharging, the chemical reaction is going on as the battery is in use.
Cheers Rob

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Fishing is all fun & games until someone loses a walleye

Rob is on the right track...

As a general rule of thumb with lead acid deep cycle batteries, the time to discharged is the inverse square of the multiple in current drawn. Said easier, if you double the current you will get about 1/4 of the time before the battery hits low voltage.

The inverse is true, if you halve the current, the charge will last approximately 4 times as long.

That's the benefit of running batteries in parallel.

The benefit of running one and having one as a spare is that careless use of power does not leave you without any

Brian

An advantage of using two batteries is being able to run a 24 volt motor. More thrust when you need it and runs at lower current at low speeds where most people run their motors. I catch more fish when I run motor slower and quieter. Unless your boat is less than 16 ft you should upgrade from a 12v to a 24 volt system. If you are over 18 ft you may consider a 36v system. Also buying the best quality batteries with the most amp hour capacity is important. You would be hard pressed to find a tournament pro that uses a 12v system. If you have a 24v (2x 12v batteries in series) that has well maintained quality batteries, you should be able to go through a full 2 day tournament with plenty of power for a third day. Windy days kill batteries. Those days force you turn you more speed way up. On those days you can kill batteries in less than 8 hrs. Good luck. BATMAN

After reading these posts and doing a bit of research it seems there are definitely some advantages of running 2 batteries together, but I'm still not sure if I like the fact that there is a possibility of being left with 2 dead batteries at the same time. It would suck if the batteries died in the middle of the second or third day on the water. Also consider the time it would take to charge 2 batteries to get you back out on the water. I've been doing the 1 battery system (with a backup battery) for 8 years now and have never been stuck without power to run my trolling motor. 1 battery is 5 years old and the other is 3 years old and they both still hold their charge like new. Unless I get into a bigger boat or motor, I don't really see a need to change what I'm doing.

Anyhow, thanks for your time and input!!

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There's something wrong with that rod.
It has a bend in it!!!

I personally run 2 batteries. This is my first year doing so and have enjoyed it so much more. The charging time takes slightly longer but not a ton. They last us over 8 hours of fishing using them on the highest power possible. And after the full day fishing. Keep the wires connected and the charge goes thru. And with 4 hours of charging on 4amp. They are at 100% and good to go for another day of fishing. Now our batteries aren't top of th line batteries and I'm sure if we went out and spent the money on really good batteries we would get even more time with them. I personally love running the 2 battery system

Just remember the first rule of batteries -whether they are AGM or lead acid, charge them up when you are done fishing for the day.
The batteries will not last as long as they should if they are used over multiple days with out recharging.

They will not charge up to their maximum capacity that way.

Larry