Is there a strong enough "portable" battery to power a Humminbird 1100's series fish finder? Looking to power at least 6-8 hours a day. Just seeing what is out there and such a thing instead of a bigger 24-27 series' battery

Been using these in my kayaks for over a decade: http://www.atbatt.com/sealed-lead-acid-batteries/b/volts-amps/m/12v-7ah.asp

Just ordered one from Amazon to power my Garmin Echomap 73 SV for $20 delivered. Its 8 amps will power my fish finder all day.

ExpertPower EXP1280 12V8AH Rechargeable Battery

Sold by: Amazon.com LLC

$19.99

You will need at least a 12v 12ah to run an 1100 for 8 hours. Just for reference an 1159ci draws 1.3ah so it will probably run right around 8 hours on a 12ah battery. About 4hrs on a 7ah. 

Not sure what "AH" stands for but is that how you calculate how long a battery will last? If it's 12 AH and your finder draws 1.3ah per hour then you just do that math to tell you how long roughly before another charge? 1.3X8-9 Hours = 10.4-11.7?

Let me know if that's correct?

31 minutes ago, mnfishing66 said:

Not sure what "AH" stands for but is that how you calculate how long a battery will last? If it's 12 AH and your finder draws 1.3ah per hour then you just do that math to tell you how long roughly before another charge? 1.3X8-9 Hours = 10.4-11.7?

Let me know if that's correct?

AH is Amp Hours

It is how long it will provide adequate power at the amp load.

So the math is actually: storage(AH) / load(amps) or 70 AH battery with 5amp continuous draw = 14 hours of use.

I use a Milwaulkee M12 extended life batteries for my Lowrance Elite-4 HDI.  I get two full days out of one.  I keep two in a Pelican case in the hatch of my Lure 11.5.

On 4/12/2016 at 1:52 PM, mnfishing66 said:

Not sure what "AH" stands for but is that how you calculate how long a battery will last? If it's 12 AH and your finder draws 1.3ah per hour then you just do that math to tell you how long roughly before another charge? 1.3X8-9 Hours = 10.4-11.7?

Let me know if that's correct?

Correct. But also factor in at least 20% loss as batteries never hold 100% of their rating. Plus a little extra as you NEVER want to draw a 12v sla or gel cell down 100%. 

23 hours ago, DogBone_384 said:

I use a Milwaulkee M12 extended life batteries for my Lowrance Elite-4 HDI.  I get two full days out of one.  I keep two in a Pelican case in the hatch of my Lure 11.5.

There is a HUGE draw difference between the elite 4 and an 1100 series bird. About 5.5 times to be exact. So divide your runtime by 5. 

I also have an elite 4 that I used for ice fishing last year, the draw is tiny with them.. 0.25ah I believe. (250mah). 

Those are 4ah batteries right? So it would power an 1100 for 3 hours or so. 

My M12XC's are rated for 4aH and the little ones 2 aH. I've never used the little ones on the kayak.

With the Hummingbird 1100 series drawing 1.3A, yeah, you'd need a much bigger battery, or perhaps a couple LiOn in parallel. Though my Lowrance owner's manual says .75A draw, which, theoretically, is roughly half, but there are many variables to consider: screen type, GPS receiver, processor, etc...

Bigger is 'always' better, so I'd go with as big a battery as you can get.