Water level in batteries

[wasilvers]

So I been noticing my main battery seems to go week after about an hour of troller use. It read 90%, but acts like it's been on the water all day long. Yesterday I checked the fluid levels, and it was a little less than an inch low (about half a cup each cell).

Have I just ruined my battery by not keeping it topped off?

How often should you check the fluid levels?

Thanks,
Will

 

[russ010]

I usually check mine after each trip before plugging up the chargers.

One other thing you might want to check is your actual charger. My buddy had a Minn Kota charger that was brand new - and on brand new 27 series Deka batts... I took my chargers over and hooked them up to his batteries - his charger said 100%, mine said 74%. I let him use my chargers for a couple of days to charge them, but the charger had already killed his batteries.

I put my volt meter on his batteries when his charger read 100%, and they read anywhere from 10.1v to 12.4v depending on each battery. All of my batteries (2 years old) read around 13.2 when fully charged.

From what you are explaining - it sounds exactly like what he just went through.

 

[Loggerhead Mike]

One other thing you might want to check is your actual charger

x2 if your battery's are gas'ing (loss of water) their probably being over charged

 

[wasilvers]

Thanks, I did leave it plugged in for a week+ when we went on vacation (I forgot about it) Sounds like that might have done it.

I wanted to go to a three battery system anyway. Now to watch for some sales.

 

[KMixson]

The faster you try to charge them the more you will lose as it boils off. A slow charge is better at keeping the level in check. An automatic charger will help at keeping the battery from being kept on charge after it has reached its full charge. The level should be above the plates inside of the battery. Always add distilled water to the battery if you add water to it. Tap water has chemicals and impurities that can hurt the batteries life span also.

 

[longjohn119]

When checking for a fully charged battery you mus let the battery rest overnight or use a tail lamp for a few minutes to draw off the surface charge. A fully charged battery that has been properly rested will read 12.7 Volts. Most charge profiles will take them up to about 14 -15 volts (Absorption charge)before shutting down so you see your 12.7 after the rest period (or you draw off the surface charge manually with a light bulb). Some charger profiles will go as far as 16 Volt at a fixed low current which is called an equalizing charge which is a controlled overcharge which does two things, as it's name implies it equalizes the voltages in each cell and it also knocks off (light) sulfate off the plates especially if it's a switching mode charger which runs at a high frequency instead of 60 or 120 Hz like a transformer based charger.

I believe most of the Minnkota chargers are switch mode and generally have good ratings/reviews, another example of a switching mode charger is the Schumacher Ship n Shore which also has a (undocumented) equalizing charge in the 2 amp setting they labeled 'watersport'. The thing I like about the Schumacher is it gives a percentage AND the actual voltage which made it easier for me to analyze the different charge profiles. The main drawback is it's noisy due to a resonant power inductor (Not the fan as commonly thought, the fan just transfers the noise) that whines at the frequency of the pulse width modulator in the switching mode power circuit. It changes frequency depending on the output current (The width of the pulse sets the voltage) and gives the impression the fan changes speeds went it actually doesn't. Also the charger has to run all the time to supply power to the microcontroller and is especially 'whiny' at a no load condition. These are minor annoyances but the charge profiles are spot on although not very well documented (Actually they are dumbed down to avoid confusion as the average consumer has no clue about charge profiles and equalizing charges)

For Ship n Shore users I would recommend using the 10 amp setting (I wouldn't go to the 15 amp setting unless you have a battery capacity of 150 amps or better, and don't confuse cold cranking amps with capacity) for recharging and then every month or two charge full on the 10 amp setting, let rest overnight or 8-12 hours then hit it with the 2 amp setting, rest again overnight and hit the 2 amp setting once more. This will do an equalizing charge on the battery as well as knock off some of the sulfate buildup on the plates making the battery last longer. Also note that if the water levels go low enough so the plate is exposed it'll sulfate so bad that it will actually bridge and short out the cell. That's probably what killed your battery, it only takes on bad cell to kill a battery.

As soon as my Ship n Shore is out of warranty I'll be pulling the power inductor and properly potting it so it doesn't resonate. It doesn't affect charging but it is damned annoying. It's the price we have to pay for outsourcing skilled manufacturing to nations with mainly unskilled workforces

 

[russ010]

my ship n shore doesn't make the high pitched noises anymore... it did, but I whacked it with my hand one good time (we had to do this to modems in our satellite terminals) and it quit

 

[wasilvers]

"Schumacher Ship n Shore" - that's what I have. I use the 10 AMP setting, unless I know for sure I will not use the battery, then use the 2 amp charge. Bought it because of the % status.

The plates were not exposed in the battery - that I could see anyway. I just saw fluid in there.

Also, it acted funny this weekend. Like I said, about an hour into fishing, the system starts acting like the battery is 'weak'. Anyway, I was on the troller on speed 4 (of 5) and it was going along fine, then in mid-move, it all started acting weak, like someone flipped a switch. The troller slowed a bit (changed pitch) and never recovered. I immediatley thought I was running through some thick weeds and got some caught on the shaft, but I wasn't even close to any. I jiggled wires and nothing. It just ran 'slow' the rest of the day. I've never seen something happen like that, be perfectly fine, then immediatly act drained.

It has to be the battery, because the situation repeats itself over and over (full battery is fine, about an hour into fishing it is 'weak') - I can't imagine the troller would have any circuits that limit it. The troller is a MinnKota Edge 55lb thrust 12 volt. Why would it happen so quickly? The battery acts drained, but the charger can show up to 90% left, usually it says 80% at the end of the fishing trip. I just keep using the battery and turning the speed on the troller up.