problem charging my trolling motor

[jasonmcintosh]

I bought my "largish" trolling motor about 6 months ago so I could fit it under my front deck. So it sat unused until yesterday. I charged it up before I took it out (using "deep cycle" setting on my charger), but it never went to "fully charged" on it. (My charger has done just fine with my regular car batteries.)

After getting some use out of it on the water with the trolling motor yesterday, I started charging it last night. However this morning (10 hours later?), it still wasn't charged. The charger has a scale something like 0, 5, 10 and 15. After 10 hours, it was still on 5. When I charaged it the first time, it got very close to 0, but not quite enough to turn the charger off. (0 is fully charged on this scale.)

After the 10 hours of charging, I could hear it "bubbling" in the motor (at least I think I did). I checked the water/acid level and it was fine in all chambers.

After using it yesterday, my trolling motor said the battery still had a good charge at the end of the day. (The motor has a battery check with 4 settings: fully charged, good, low, and recharge. It was on the 2nd to the highest after using it for the day.)

I've never had a deep cycle batter before and I'm wondering if the battery is ok, or it I should give it another 10 hours to charge? Comments?

Jason

[flydangler]

Something ain't right!

What is the prior useage on your deep cycle battery? How old is it? How big (Reserve Capacity) is it"

Is the water level full in ALL cells? Are the terminals clean and corrosion free?

Was it fully charged before you let it set over the winter? Where was it stored? Did you do a mid-winter recharge?

Did it sit in a very cold (below freezing) place in a discharged state for a long time? What's the temperature when you last charged it?

I get about 4 to 5 years of heavy use out of my deep cycle batteries. Have always tried to keep them from freezing, recharge them to full right after each use and at least every 6 weeks when stored, and never put the charger on them below 36 degrees F.

[jasonmcintosh]

flydangler,

It sat in my garage for about 6 months straight from the store. I'm in South Florida, so the temp was probably around 80 F for most of that, rarely got below 60 F, certainly never below 40 F.

Never used it during that time. Just bought it for mechanical fitting. All cells are up, no crossion anywhere. For some reason it was covered with fairing dust (along with everything else in my garage ).

Still got the warrenty on the battery. Just wondering how long it takes to charge one of those.

Something I didn't mention is that I was charging it on the 2 A setting, not the 5 amp setting. But 10 hours is a pretty long time...

Jason

[ArizonaBuilder]

Here is a very good link to deep cycle basics with links to individual battery manufacturer's websites. The Trojan site has very good tech articles on deep cycle batteries.

http://www.windsun.com/Batteries/Batter ... 20Charging

Excerpt from referenced URL..

Most flooded batteries should be charged at no more than the "C/8" rate for any sustained period. "C/8" is the battery capacity at the 20-hour rate divided by 8. For a 220 AH battery, this would equal 26 Amps. Gelled cells should be charged at no more than the C/20 rate, or 5% of their amp-hour capacity. The Concorde AGM batteries are a special case - the can be charged at up the the Cx4 rate, or 400% of the capacity for the bulk charge cycle. However, since very few battery cables can take that much current, we don't recommend you try this at home. To avoid cable overheating, you should stick to C/4 or less.

Charging at 15.5 volts will give you a 100% charge on Lead-Acid batteries. Once the charging voltage reaches 2.583 volts per cell, charging should stop or be reduced to a trickle charge. Note that flooded batteries MUST bubble (gas) somewhat to insure a full charge, and to mix the electrolyte. Float voltage for Lead-Acid batteries should be about 2.15 to 2.23 volts per cell, or about 12.9-13.4 volts for a 12 volt battery. At higher temperatures (over 85 degrees F) this should be reduced to about 2.10 volts per cell.

Nearly all batteries will not reach full capacity until cycled 10-30 times. A brand new battery will have a capacity of about 5-10% less than the rated capacity.

[Doug]

I have noticed that my deep cycle batteries seem to take longer to charge than a starting battery. Also 2 amps is a slow trickle charge and will take a long time anyway.

[Eric]

Sometimes 1.5 and 2 amp chargers will only to maintain batteries and will not actually charge a low battery. Charge it up with the 5 amp setting and that might do the trick.

Cabelas has some fully automatic chargers for a good price, I got mine, a 6 amp fully automatic for 40 bucks. You can put it on and forget it till you want to use it again.

[jasonmcintosh]

Mine is automatic, but I've never had to charge a battery this much. I'll run it on 5 amps tonight and get back to you guys. Thanks, it's great to get support here...

Jason

[Boomer]

If you let it sit in your garage for six months, and if you let it sit on a concrete floor, you may have damaged the cells.

If it were mine, I'd take it to the local gas station and ask them to put a "fast charge" on it. This is where they have a high powered battery charger on it. Should cost you $3-5.

If it won't take a "fast charge its probably damaged, and hopefully, you cna replace it under warranty.

Also the meter on a charger is only a fair approximation--- sort of a go-no go situation. You can get a battery guage through any marine supple catalog that will tell you how much charge your battery has. Especially handy out on the water.

[odras]

Ok

[jasonmcintosh]

Actually the higher charge rate was 15 amps, and it went to "fully charged" in about an hour at that rate. Guess it charged just fine after all.

Thanks for the comments. I've never owned a motor boat before, so alot of these details are new to me. Now I own one that wants to jump out of the water... (Read my "BLUE GF18" thread... in Builders Power Boats)

Jason