Fishfinder Battery / Lowrance Elite 4 Combo Gold

I know there are lots of postings on this subject but I just don't seem to be able to get the battery life others are getting.  I just installed a new Lowrance Elite-4 Combo FF & GPS (color) and I'm only able to get about 8 hours of operation from an 8AMH sealed lead battery.  According to Lowrance the draw is about .75 amps per hour.  What's puzzling to me is that the battery reads 14+ volts when I take it off of the charger and after running the FF for about 8 hours and it shuts itself off, the battery still reads 12+ volts.  I'm using 16 gauge braided copper automotive wire from the battery to the unit, so I don't think resistance is an issue.  All splices are soldered and covered with shrink tubing.  Am I just expecting more than what I can realistically get from my battery?  Is there a better battery that might provide for 2 days of fishing.

Thanks,

Martin

A couple things ... first, check that your auto shutoff isn't somehow set to 12V.  You should be able to set it lower.

Second, when checking the battery level, it's best to do it under load.  Now, this is going to be hard to do, as you can't turn the fishfinder on to put a load on it.  But try anyway.  Plug in your ff, put a voltmeter on the battery, and hit the power button.  See if you get a drop on the voltage.

-Allen

Is it a new battery?  If it's an old one, I suspect a "leakage" problem since it can't hold the charge as it should.  Your FF should be working fine at 12+ VDC unless the battery is bad or the setting on your FF is set to shut off at 12.x VDC.

It should operate down to 10V.  It is possible for the battery to produce 12V, but not enough amperage to power the unit (~1amp).  Is the battery new?

~Bill

It is possible for the battery to produce 12V, but not enough amperage to power the unit (~1amp).  Is the battery new?

   Yeah, that was what I was getting at when I said to try under load.  It won't continue to produce 12V though, it will droop to something lower.

-Allen

Martin,
I had switched over to all Lithium setup and would never look back. I use a Lipo 4s 14v 5ah battery on my ff. It would last me all day on my Humminbird 597ci.

You can use a amp meter to find out for sure how much your ff is draining.

I know there are two camps on this subject. There are pros and cons on lithium vs SLA batteries, but I feel the pros on lithium outweighs the cons.

Lipo
-------
Pros:
half of the weight of SLA of equal capacity
compact (less than half the volume of SLA of equal capacity)
sustained high constant output
retains charge in storage (much slower drain)
fast charge (if you want to)
many configurations to choose from
last 1000+ cycles

Cons:
*** safety (must not short or will generate immense heat = fire hazard) ***
30% higher cost than SLA (my 5ah battery + smart charger costs around $80)
must not over charge/discharge (same for any battery type)

If you take precaution, lithium batteries can be use safely. I helped four guys convert thier setup to Lipo and have never heard a complain. The thing I hate most about SLA is that they lose charge so quickly when in storage. And, they only last 2-3 years before rapid decade.
Remember the live-well you sold to me? I charged up the SLA in that live-well before last year's Islander trip. Tried to use it one day later and it was DOA 

Anyhow, good luck with whatever you find. I'm actually setting up a battery box for one guy right now. Let me know if you'd like to see pictures of the setup.

ernest

I'm actually setting up a battery box for one guy right now. Let me know if you'd like to see pictures of the setup.

Yes, please! 

And to confuse matters, there are more than one type of Lithium batteries, both with their own pros and cons ... Lithium Ion and LiPo.

Gotta love the 14V LiPo.  I'm going to have to take a look at the spec sheets and see what that is equivalent to in a 12V battery.

I have some Lithium Ion batteries that I'll be fooling around with this year.  First thing to note, there is some unscrupulous specmanship  going on.  I have a 10000 mAH battery, but that spec is before internal voltage conversion/conditioning.  In reality they are closer to 7000 mAH (7 AH) batteries.

They do come with USB ports and I can charge USB devices off of it in a pinch!

-Allen

Gotta love the 14V LiPo.  I'm going to have to take a look at the spec sheets and see what that is equivalent to in a 12V battery.

1s = 3.7v nominal voltage, fully charged at 4.2v. (Meaning, 3s = 11.1v nominal/operational) It will power up the ff, but I use 4s, which is 14.8v nominal. Since ff can operate between 10v to ~20v, I went with 4s.

Martin, if your SLA measures no-load voltage of 12v or less. It is depleted. When under load, I imagine it would drop below 10v immediately. If you were using Lipo cells, you can carry one more battery if you want to fish two days straight. The two batteries combined weight less than one SLA. Just a thought.

I have some existing photos in Photobucket...











The charger. It can be powered by your car battery or by AC. 35$ - 45$.


and this little guy can power my Lowrance 350c for 3 hours if I want to go lightweight...

I believe the Lowrance unit in question can operate from ~10v to ~17v.

Thanks for all of the replies.  I'm gonna check the setting as Allen suggested.  I guess if that isn't the issue, I have some decisions to make.  I like the lead acid battery because I have the Hobie battery holder that fits in the rear hatch.  It allows me to make use of what was previously a useless hatch and I like the idea of getting a little weight as far back on the yak as possible.  It's also an easy solution to providing a dry environment for the battery and wiring.  If I can get 8 hours of operation, that's probably a full day on the water for me anyway.

You can always look into LiFePO4.  Especially, the Lead Acid replicable battery type. 

http://www.batteryspace.com/Li-Ion-Batteries-To-Replace-Lead-Acid-Batteries.aspx

Ive been using a 3 cell RC car hard pack Lipo for a year now. No issues, lasts all day and re-charges in 30-45min. Its the size of a large candy bar, cost $50-70.

Alright Martin.  I believe the type of battery that you are using is rated at 7 AH and if I understand you right that fishfinder which also has the GPS and draws .75 amps an hour.  By my calculations, you should be getting about 9.3 hours of battery life with that battery.

But I would also check the minimum voltage setting on your unit too.

I don't believe the "cut out" voltage has a user setting on a Lowrance unit.  I'd have to look at my Elite 4 but I believe that is a factory setting in the ~10V range.