Dedicated battery for DF/FF question

[Clint]

I am in the process of rebuilding a 1985 Monark 16” bass type boat and while planning I realized I have an extra battery. But here is the thing, it is a gel cell battery and does not do well as either a trolling motor or a starting battery. It was designed to power electronic equipment so I am considering using it to power my HB Helix 5 DI GPS, and another DF I plan to install on the boat.

I know some of the upside of this, such as not having to worry about trolling motor noise on the DF/FF but was wondering if anyone can think of a downside other than the extra weight. There is plenty of room under the rear deck so space is not a factor.

Can anyone give me a reason not to use it or another reason I should use it?

[wannabe fisherman]

sounds like you've got a good plan, I can think of no reason not to use it.

[rnvinc]

Get a small on board charger and you'll be set ...

Rickie

[Cane Pole]

This will work, but it is still subject to all the interference noise.

[jimp]

Make sure the battery charger is compatible with gel type batteries.

[Clint]

This will work, but it is still subject to all the interference noise.

Not ALL - noise is either induced or conducted.

Induced (sometimes referred to as common mode noise) means it comes through the air, or in this case the water and it will still be subject to this type.
Conducted comes through the wiring such as the power wire. With the FF/GPS and the DF the only things on the battery this source of noise will be eliminated.

I will use a shielded cable to run the power to the electronics, grounding the shields at both ends to eliminate as much noise as possible. Being a Amateur Radio Operator I have lots of cabling and wiring available.

Make sure the battery charger is compatible with gel type batteries.

I have a few different gel cells in use for different things and I have a variable voltage power supply with current clamping that I use to charge them. It is not a "set it and forget it" set up but it works. I just monitor the current being pulled by the battery and shut it off when it starts to flatten out.

[BobB]

How many AH is the battery?

[Clint]

How many AH is the battery?

I have a couple I can use, one is 8AH which with my Helix DI GPS drawing 650mA should last about 12 hours and the other is the size of a car battery.

[Cane Pole]

Ok. But, I will stick with what I stated.