Best Way to Bring Back Discharged Battery

Jacalore

Jacalore

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Bought a new marine starting battery last summer. Winterized in November, disconnected all leads to battery. Probably should've attached a solar trickle charger, but I didn't. I'm hoping I didn't damage it. What's the best way to bring it back? I'm assuming it's discharged. I have a multi-stage charger, don't think it's a smart charger tho... any advice appreciated. Thanks.
 
S

Starcraft5834

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Re: Best Way to Bring Back Discharged Battery

Best Way to Bring Back Discharged Battery? buy a new one........

give say Walmart a call and see if they will test it for you..... you will need a diagnostic of the battery health,, or lack thereof,, to know for sure
 
oldjeep

oldjeep

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Re: Best Way to Bring Back Discharged Battery

Why are you assuming it discharged?

Assuming you actually tried it out and there was a problem, you could put it on an automatic battery charger on the 2Amp setting and see what happens. However if you really did just disconnect it and it is acting totally discharged I'd assume it froze too hard.
 
GA_Boater

GA_Boater

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Re: Best Way to Bring Back Discharged Battery

Almost any battery has a minimum one year warranty. Charge it and if it won't hold, take it back.
 
Jacalore

Jacalore

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Re: Best Way to Bring Back Discharged Battery

I haven't checked the battery yet, boat still under tarps. Just trying to formulate a plan of attack. Didn't consider it would still hold a charge over the winter. Thought I read where a battery can be damaged left uncharged over a long period of time.
 
oldjeep

oldjeep

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Re: Best Way to Bring Back Discharged Battery

Jacalore said:
I haven't checked the battery yet, boat still under tarps. Just trying to formulate a plan of attack. Didn't consider it would still hold a charge over the winter. Thought I read where a battery can be damaged left uncharged over a long period of time.
Click to expand...

Meh, very few boat batteries are on chargers during the winter. You disconnect them in the fall, reconnect in the spring and maybe toss a charger on to top them off but I rarely even do that.
 
H

Home Cookin'

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Re: Best Way to Bring Back Discharged Battery

mine ride through the winter just fine without charging or anything. don't assume you have problems; you will have enough real ones anyway.
 
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UncleWillie

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Re: Best Way to Bring Back Discharged Battery

Jacalore said:
I haven't checked the battery yet, boat still under tarps. Just trying to formulate a plan of attack. Didn't consider it would still hold a charge over the winter. Thought I read where a battery can be damaged left uncharged over a long period of time.
Click to expand...

I pulled my battery last October and it has been sitting the the garage ever since.
I put a meter on it every month just to check how it is surviving.
It is still reading 12.7 volts after 6 months without any topping charge.

Your Plan of attack...

Before you touch anything electrical in the boat; don't even toot the horn; Measure the battery voltage.
If it still above 12.3v is is likely still just fine.
If it is below 12.0v, the prognosis is not so good.

In either event, charge it for a day and then let it stand disconnected for 24 hours.
If it is under 12.5 after a day, replace it, otherwise worry about something else. :D


The Best Way to Bring Back a Dead Battery? ...
Trade it in and Bring Back a new one!
 
Last edited:
tpenfield

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Re: Best Way to Bring Back Discharged Battery

Jacalore said:
What's the best way to bring it back? I'm assuming it's discharged. I have a multi-stage charger, don't think it's a smart charger tho... any advice appreciated. Thanks.
Click to expand...

If I were me, I would just charge the battery and see what you get.
 
Jacalore

Jacalore

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Re: Best Way to Bring Back Discharged Battery

Thanks everyone. Maybe I over-thought this one. We'll see soon enough. Hope to break her out of her cocoon in a week or so... I hope y'all are right!
 
Grub54891

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Re: Best Way to Bring Back Discharged Battery

I've never charged them or took them inside in the winter. Just unhook, and re-hook in the spring. If it won't crank,charge and test. Get 5+ years out of them.
* you'r results may vary.....
 
H

H20Rat

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Re: Best Way to Bring Back Discharged Battery

Your battery is fine, you are over thinking! You did the smart thing and disconnected the leads. ANY draw, even the clock in the radio or the engine computer, would have destroyed your battery. (by destroyed, I mean completely flattened. There is no way I'd trust a completely discharged battery on a boat)
 
Jacalore

Jacalore

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Re: Best Way to Bring Back Discharged Battery

Okay, I couldn't stand the suspense, so I pulled the tarps off the transom area and measured the battery. 12.37 with a digital multimeter. I hooked up the charger and put it on the lowrst setting (2, 10, 25) and ill chsrge it for the balance of the afternoon. It should hold up around just short of 13v after charge, no load?
 
U

UncleWillie

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Re: Best Way to Bring Back Discharged Battery

12.37 means you still have 70% of the Charge Remaining from last year. Good!
It will probably start the engine without any additional charge.
Immediately after charging, the battery may measure over 13v. Means nothing.
Wait 24 hours and measure again. Expect to see 12.6 or 12.7 but no more.
Below 12.5 will indicate a problem.

If it took 6 months to get to get down to 12.4, I would suspect you will not see anything but the best.
Don't forget to check the water level in the cells AFTER you charge it.
 
Last edited:
bruceb58

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Re: Best Way to Bring Back Discharged Battery

Your battery will last a longer if you can somehow keep it fully charged all winter. Even letting it drop 30% over the winter will shorten its life. It's a matter of convenience vs optimum battery maintenance that you need to weigh.
 
Jacalore

Jacalore

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Re: Best Way to Bring Back Discharged Battery

I plan to use a solar trickle charger next off season. Good insurance.

I like the beer approach!
 
Jacalore

Jacalore

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Re: Best Way to Bring Back Discharged Battery

Charged boat battery yesterday for a few hours. Today it reads 12.63
So I should be good. Thanks everyone for the education
 
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