Cordless drill batteries

For the last couple years I have been running drill motor batteries in my two kayaks with good luck.

My two fishfinders are small black and white Humminbird 170's that appear to draw very little juice.

The battery in my Big Game 2 is a Dewalt  ten year old 12v and on a bench test ran the FF for over 18 hours, good for a very looong day on the water.

The other yak is a wood sit inside and uses a 14.4v Hitachi, also about ten years old. No bench test on this one. It also powers a small 550GPH bilge pump in case of a real bad day and pumping the cockpit dry is needed. I have run the pump 50 min. That's a lot water pumped!...

Granted, these batteries are powering  pretty low draw fish finders and I don't how well they would work with bigger color finders with all the bells and whistles but they work fine for my little finders. They are also real easy to hook up and recharge in a couple hours with the drill motor factory chargers.

I don't use dry boxes with the batteries but contractors seem to have no problems  working in the rain with the drills for years.

Anybody have any idea what the AMP ratings of these batteries are? I haven't found any numbers on them.....Warf

Interesting.  Could you explain how you rig those up and connect them to the FF?

Sure...The Dewalt uses automotive spade connectors available anywhere, they are even marked +- so hookup is easy, the FF power cord just needs a couple female spade connectors crimped or soldered on. I soldered them then used shrink tubing.

The Hitachi is a little more tough but doable. I did it the easy way. I had the drill motor that the chuck went south on so I just sawed the battery part off and figured out where to connect the FF wires and it worked out perfect. If you hook the FF power up backwards, no big deal, it just won't work so reverse the hookup and your good to go....Warf

Nice, that's a pretty good idea!  Sorry but can't help you on the amps on those.  Maybe call the company?

If you go this route make sure you have a inline fuse in the system somewhere, better safe than sorry.

Also, I would not try much more voltage than 15 volts. The manual with the FF says 12 to 20 volts but some of the 18v batteries put out 22 volts, hate to see smoke coming from the unit..LOL...

Both my batteries are about 10 years old, I would think newer ones would give you more run time.....Warf

I was going to do this with my 20v ions 3ah . dewalt sells a usb top piece that slides on the battery , you can charge phones or whatever, I was going to spilce my fish finder wires to a usb connector and just run those batteries, light and last all day. Im glad someone else tried something similar. cheers

Your FF will likely not run on 5 volts.

The Ah ratings can be pretty confusing.    The  Dewalt 12 or 14 batteries are stamped as being 1.5 to 3.0 Ah for their Ni-Cd and Ni-Mh versions.  I think though am not certain but by the time they came out with their Lithium batteries,  they dropped the 14 volt systems.  Even stepping up to their 18 or 20 volt Lithium batteries look to only provide up to 5 Ah based on their labeling.

What seems confusing is that the higher capacity Anker battery states to be rated at 20,000 mAh which converts to 20 Ah  Even if the 20,000 is it's rating for it's 5 volt output,  I am guessing it's 12 volt output would still be around 12,000 or more.   To add to the confusion,  there are $500  LiFePo batteries rated for up to 4.0 L automobile engines which state to only have 10 Ah.  They state that is equal to 30 Ah PbEq Lead Acid equivalent.

    my brain now hurts.

I do like the idea of the quick charging times with power tool batteries.