dedicated battery for electronics

[bassdge]

with all the talk about dedicated batteries for electronics and using tool batteries, has anyone looked at smaller 12 volt lithiums?
when I ordered my lithium batteries for my trolling motor, I noticed this 12 v 21ah lithium battery: FuelZero 12v 21AH Deep Cycle LIFEPO4 Battery
would that be sufficient to run a 3 graph set up?

[bassdge]

also Dakota Lithium 12v 23Ah Battery - Half the Weight & Twice the Power

or other brands in similar size/weight/ah

[LWINCHESTER2]

Just do the math. Add up the draw from the specs for whatever graphs you have and whatever else you'll connect. Then multiply that times the number of hours you'll be fishing. That will tell you how big of a lithium battery you'll need.

[ampdreamer1]

I don't understand why people do this. Just use 2 batteries wired in parallel on your engine. Atleast that way the alternator will also charge it.

[LWINCHESTER2]

It just depends on how much you have hooked up to draw current. If you hook up enough, 2 won't last.

[Ranger_Rick]

I went with a 60AH dedicated battery for 3 graph setup. 21AH is not enough if you are running 3 graphs with Livescope if you want 8+ hours of fishing. You dont want to run those batteries flat dead every time you go out....if you want to get 5 years of life out of a battery. Example: rough math....1.5 + 1.5 +2.0 + 3.0 (LS) = 8 amp per hour X 8 hours = 64 AH needed.

[JFB]

Take for example this set up, what battery set up would you do:

At Dash: 12 Helix mega and 12” garmin

At Bow: 12 Helix and 12” garmin for livescope.

The plan was one Agm starter battery.

[lunker56]

I have a 12 inch garmin a 7 inch garmin, a 9inch lowrance--brand new agm 31 battery. After 5 hours of fishing, my voltage on Garmin said 11.5v. According to Garmin suuport, anything under 12.4 distorts quality. Wondering what to do

[LWINCHESTER2]

.......According to Garmin suuport, anything under 12.4 distorts quality.

That contradicts their specifications for power for their units. The spec says power should be 9v-18v for some and 10v-32v for others. If performance was better at one voltage and worse at another voltage I think I would have noticed. Before I got a lithium battery. on a long outing my voltage would often go below 11v.

[Todd Driscoll]

I have a 12 inch garmin a 7 inch garmin, a 9inch lowrance--brand new agm 31 battery. After 5 hours of fishing, my voltage on Garmin said 11.5v. According to Garmin suuport, anything under 12.4 distorts quality. Wondering what to do

To follow what Leonard said, if voltage is within the specified operating range the sonar quality will be the same. Doesn't matter if it is 11.0V, 12.8V, or 18V. If voltage drops below the specified range, the sonar will shut off rather than degrade the image. This info is straight from Garmin engineers.

[lunker56]

Thanks Todd--that makes more sense then my phone call with Garmin Support