dual battery

Ok so I decided that, I am not going to buy an expensive LiPO battery and instead I will be running 2 batteries. This will give me a total of 7ah+9ah. So 16ah. Realistically the 7ah battery is more like a 4ah now. So I will have enough juice to fish all day with full back light and running dual beam.

Easy to do. Just run the batteries in parallel. Wire + to + and - to -. Keeps it at 12 volt but more storage.
If you wire in series. You keep the capacity but increase the voltage. Hope to post pics once the new batter shows up. Possibly wiring a hard wired charger port as well. So I don't ever have to take the batteries out.

Another option would be to carry an 8/10X AA Battery pack with you for when your main battery dies.  Usually have a 9v style connector on them, I just add female clips to a 9v battery adapter and then it's easy to connect. 

Can also get an 18 or 22amp SLA like this: http://www.amazon.com/dp/B009CX04RU?psc=1
That's what I had to get to power my livewell, nav lights, and FF on my Ultra 4.7. And it weighs less than two standard 7amp batteries.
You mentioned one is more like 4amps...is that because it's old? If so, I can give you another 12v 7a SLA for free...I have 5 or 6 of em. 

An just to throw you an idea on the charger, go pick up a battery tender from walmart or a hardware store. They come with fused end harnesses so that you can keep them attached to your car/motorcycle/lawnmower, so just clip the terminal connections off of one of them, wire into your battery, and run the cable outside the box. Just did this with my thresher, so easy to just wheel it into the garage after fishing and plug it in and leave it until I take it out again. Keeps the battery charged and conditioned, and I don't have to remember to charge, ever! 

Another option would be to carry an 8/10X AA Battery pack with you for when your main battery dies.  Usually have a 9v style connector on them, I just add female clips to a 9v battery adapter and then it's easy to connect.

This is what I use as my primary battery.  I get about 24 hrs of use, but don't use dual beam or back light.  My FF is a Huminbird piranha max. 

Can also get an 18 or 22amp SLA like this: http://www.amazon.com/dp/B009CX04RU?psc=1
That's what I had to get to power my livewell, nav lights, and FF on my Ultra 4.7. And it weighs less than two standard 7amp batteries.
You mentioned one is more like 4amps...is that because it's old? If so, I can give you another 12v 7a SLA for free...I have 5 or 6 of em.

It's because it's old. It came with the yak. I appreciate the offer for the battery. I am slammed the next few weeks at work. If I get a chance and our schedules line up I will take you up on it. Let ya know as soon as I can.