One Batt Only-Expected Life

[forefrazier]

I am taking measures to simplify things on my yak and want to know if anyone is running just a single battery for both their bait tank and FF? I have a timer switch on the bait tank so it is not running the entire time. Will a 12v 7ah do it for average running time of 6hrs?

[esdees]

Probably. I use the same size for just my bait tank and it can run constantly (no timer) for almost six hours. I keep it simple by using two separate batteries. Plenty of people use just one though.

[Handymansd]

It is entirely dependant on the pull of your ff and pump, and the capacity of your battery (memory: batteries tend to do better if you totally discharge them before re-charging them). Having said that, If all is within normal limits it should last all day long with a timer running reasonably often.

my .02

btw, a couple of my 7ah batteries out last my 10ah batteries by 4-5 hours of use!! go figure.

[Craig jones]

Handyman, do you run your batteries down before you put them on a charger? I know I have always done that with cordless tools.

[dgax65]

I think that is more important with NiCad batteries. They (especially older models) develop a memory if not put through a full discharge/charge cycle. Sealed lead acid batteries last longer if NOT fully discharged. It is best to keep them on a trickle charger when not in use. SLA won't develop a memory like NiCads.

[lamb]

Originally Posted by dgax65

I think that is more important with NiCad batteries. They (especially older models) develop a memory if not put through a full discharge/charge cycle. Sealed lead acid batteries last longer if NOT fully discharged. It is best to keep them on a trickle charger when not in use. SLA won't develop a memory like NiCads.

Ditto on that Doug. I learned the hard way.

The lead acid batteries we're commonly using to power bait tank & fish finder should be re-charged regardless of how much juice there's left in them. Their capacity is slowly shrinking over time though, a normal thing. I usually loose connectors to the corrosion before the battery life shortens beyond what would bother me, so I end up replacing them.

NiCad batteries are a different story - they should be completely discharged before re-charging to avoid developing "memory" and shortening the battery life. NiCad type batteries are often power the hand held VHF radios we're using.

You should be fine with a single 7Ah - 8 Ah battery, especially if your bait tank is on the timer switch. It is a good idea to always have a spare.

[Handymansd]

Originally Posted by Craig jones

Handyman, do you run your batteries down before you put them on a charger? I know I have always done that with cordless tools.

Yes, I actually store my kayak on the ceiling of my garage / shop by using a 12V portable winch. I finish fishing, then use the left over juice in my batteries to run the winch to lift the kayak to the ceiling. It works great, and no storage problems.

I do keep all of my 10 batteries rotating through a trickle charger though, it doesn't seem to shorten their life or develop any "memory" though. I agree that they all seem to lessen their life over time but as Adi said the shortened life is so minuscule that it doesn't bother me and some of my batteries are like 4 years old and still work just fine.

[Handymansd]

For those that really want to know the ins and outs of electrical storage there are a number of good sites on the internet. Here is a really simple explanation of the basic types.

http://www.windsun.com/Batteries/Battery_FAQ.htm

Depending on your application, heat, storage conditions, etc. you should be able to expect approximately 1000+ charge and discharge cycles. A trickle charger used with AGM or Valve regulated rechargeable batteries WILL permanently damage and result in reduced capacity due to overcharging. Likewise using something like a car charger for a SLA battery will destroy it. I like the Valve regulated rechargeable as they they are equipped with a low pressure venting system, which releases excess pressure from overcharging if necessary.

I have this fascination with a solar powered kayak... Just have not implemented it yet. I will be talking to Doug when I am ready...

[dgax65]

Bad news: the photovoltaic array required to run a FF and pump all day is going to be very large.

Good news: it will be big enough to use it as a sail

Stick with batteries.