Battery Charging ?

[N1265]

Hi Guys,

I am trying to charge my marine battery and I am a little confused.

I have an old Charger that I have always used for my car batteries and thought it worked pretty well, However when I try charging my marine battery on the12v/10A setting it does not seem to want to " come down " to a charge. But if I switch it to 12v/2A it shows charged.

I had it on the charger for 4 hrs yesterday and 4 hrs today at the 12v/10A setting but the needle never moves and now I am starting to wonder :

1) Does it takes a lot longer to charge a deep cell battery .

2) Is there something wrong with my charger / battery.

3) Or Is everything normal and I am just having one of my many "Brain Fade" moments.

What do you guys think ?


Also, When you guys charge your marine batteries, what setting do you use and how long you leave it set on the charger ?


Many Thanks,

 

[Silvertip]

Re: Battery Charging ?

Your battery does not show a charge on the 10A setting but it does on the 2A setting because the battery IS actually charged. The charge rate tapers off as a battery becomes fully charged. The 2 amp setting on your charger is intended as a "maintenance" charge -- meaning it is used to keep a battery topped off once it is charged.

Batteries do not like to sit in a partially discharged state over long periods so the object is to get the battery topped off as quickly as possible. Standard deep cycle or starting batteries can be safely charged at charge rates up to 20% of the amp/hour rating. If the battery has a 100 amp/hr rating it can be charged at up to 20 amps.

Many boaters these days use modern "smart chargers" that take the guess work out of battery charging. Plug it in and forget it. Battery maintainers (small 1.5 - 2 amp) are typically used on starting batteries that don't get deeply discharged and 6 - 20 amp smart chargers are used on trolling motor deep cycle batteries since they do get deeply discharged.

 

[Deadwood]

Re: Battery Charging ?

Good info on the subject: http://www.youtube.com/watch?v=4ie6mRztCvI

 

[N1265]

Re: Battery Charging ?

Thanks for the link,

Do outboard motors come with a charging system ? like a car ?

 

[Silvertip]

Re: Battery Charging ?

Depends on how big the motor is but most engines do have a charging system. "Like a car" comparison caused a long detailed discussion regarding a similar question but YES -- it is SIMILAR to a car in PURPOSE but NOT in HOW it is accomplished.

 

[1fishbone]

Re: Battery Charging ?

THANKS...I learn so much here!