Stupid question for everyone who uses small batteries for electonics

[b turdy]

So I have a fish finder I want to try out on the ice this year, but no power source.  however i did think about this.  would a rechargeable cordless drill battery work just the same way?  I know they are a lot more expensive, but i have them and I'd rather not go out and buy a battery specifically for this reason especially if i dont use it often. 
Here's a battery I found on the web....

Specifications •Volts: 12
•Amp Hours: 1.3
•Length (in): 3.82
•Width (in): 1.69
•Height (in): 2.28
•Weight (lb): 1.21
•Terminal: F1


Here's the drill battery I have

Charge Time: 40-Minutes
Voltage: 12V
Battery Type: Lithium-ion
Battery Amp Per-hr: 1.2 Ah
Rechargeable: Yes
Dimensions (L x W x H): 5.51-in x 2.83-in x 4.92-in

I know there's a .1 Amp per hour difference, but i wouldnt think that would matter too much?   What do you guys think?

[UP jigstick]

If this just a one time experiment to see if/how the flasher will work, I'd say go for it. You may have to 'fiddle' with the wire/battery connection some to keep the juice flowing. Anything more the that and I'd spend the $20.00 bucks, or so, for a dedicated 12v 7ah battery.

[onebadc20]

You need to know what your fish finder draws to figure out what size battery you need.  Heres a link to a page to help you figure out your amp draw. http://kayak-angling-ireland.org/rigging/electrics/what-battery/

Both batteries you suggested probably don't have enough amps to run the unit.  You can get a 12V 7.5ah battery for under $20 off the internet.  That would be the way I would go.

[wax_worm]

Most Vex/Marcum use batteries that are 7-9 amp hours and weigh more than 1.2 lbs.  It may work but I don't think you are going to get much fishing time out of a 1.2 ah battery.  You can find the sealed lead acid batteries for under 30 bucks in most places.

[Idahogator]

 Hey B T, Just a word of caution on those cordless drill batteries. Very often there are several contacts on some, so use of a VOM will aid in preventing reverse polarity, which could FRY/RUIN your sonar(fishfinder). A wheatstone bridge between those batteries and the sonar will avoid reverse polarity.
When my brain gets cold the sparks fly. So, good luck with your risks.

[lefty2053]

I use the battery in the top picture. I will check the Amps. I have 2 of them. I used them for my Fish Finder on the ice and also used one for the Fish TV I used to own. Cabelas sells them with a charger for around $29.

[vexvision]

A battery with not enough power= short day on the ice..............get the appropriate battery for your unit, you wont regret it!

[lefty2053]

Just checked and the Cabelas battery I have is an 8.0 AH. But works fine with my Eagle FishMark 320. Fish Finder.

[campfindit2]

I once used a 12v Dewalt battery to drive an indoor 12v track light on my mtn bike. It worked slick. Amp hours indicate run time. Fashion a connection and test it for run time.

[Snakehunter]

I used the universal battery you see in the top picture with my Eagle FishEasy 3 portable. I bought mine at a Canadian store - Princess Auto for about $15.
Charged it with a regular automotive battery charger and kept it indoors when not being used. It lasted for years. The same type battery is in my new Humminbird Ice35.

I don't know the secret to rechargeable tool batteries. I own a couple 14V drills and I kill the batteries in a year. I try to completely flatten them before recharging and always keep them warm but they still develop 'memory' and end up useless.

A buddy who is a contractor swears by hs Dewalt tools and never has battery issues. Who knows

[Woodsman]

I used the universal battery you see in the top picture with my Eagle FishEasy 3 portable. I bought mine at a Canadian store - Princess Auto for about $15.
Charged it with a regular automotive battery charger and kept it indoors when not being used. It lasted for years. The same type battery is in my new Humminbird Ice35.

I also use a similar battery to the first one pictured but definitely not the same one.
Snakehunter if you check the dimensions & amp hrs of the pictured battery I'm positive it's not the same one as in your Ice 35.

[esox_magnum]

All battries in flashers and newer cameras are 7,8 or 9AH....

[rks-icer]

It is well worth buying an 8amp hr battery. Mine is going on its 4th year and still going strong. I put it on the trickle charger after each time I use it. Ebay has some good deals on them

[jigginPig]

Check your local electrical supply house...7 ah for about 13 bucks at our local supplier-Pig

[kb]

Most fish finders draw approximately .25 amps of current at 12 volts so a 4AH battery should run about 16 hours on a single charge in ideal conditions. The runtime will be less If you operate it with the display's backlight on.

You have to look at what you ff actually uses, than figure how long you will be out.  I used to run my gps/ff  off a pack of 8 AA batteries in a holder from Radio Shack.  It would last a solid day of fishing in my yak.  This was with a black and white screen.  A color screen will use more.

I upgraded to a hummingbird 788, and had to go to a 12 7 amp.  Id just spend the $ on a 7-9 amp batt as the cold will affect the batteries, and the extra amperage will keep you in business.

Ive seen some people use cordless drill batteries, but I dont know how long/well it works in the long run