A battery question

[Vlad D Impeller]

what is an appropriate amount of time to recharge a deep cycle trolling motor battery?

This Battery was run low but sat idle in my garage for a couple of months and went completely dead.

 

[ZmOz]

Re: A battery question

Battery amp hours divided by charger output in amps plus ten percent.

 

[LubeDude]

Re: A battery question

Put a 1.5 trickle charger on it and leave it. It may take awhile to bring it back. It might not ever come back but your chances are better if you go slow. If you can`t get it back then take it to a Battery Exchange if you have them and they have force chargers that can save a deep cycle where you can`t.

 

[Vlad D Impeller]

Re: A battery question

Its been on the charger for the last 36 hours, is that normal in a situation such as this?

 

[Bob_VT]

Re: A battery question

Well if it is 650 amps and you used a 2 amp charger do the math 650 divided by 2 = 325 hours so whatever your charger is multiplied by 36 will give you the answer.

Be patient.

 

[Vlad D Impeller]

Re: A battery question

Thanks fellers.

 

[ndemge]

Re: A battery question

Bob...... cranking amps and capaicty not the same...

good deepcycle is around 100ah capacity

 

[18rabbit]

Re: A battery question

Put a 1.5 trickle charger on it and leave it. ...

It might be worth looking into this. Flooded deep cycle batt typically benefit from a much more rapid charge, i.e. about 20% of the batt’s capacity, up to as much as 40% for flooded cell batts. Trickle charging (max of 1 to 2% of the batt’s capacity) is good to maintain a batt after it is fully charged.

 

[ZmOz]

Re: A battery question

Flooded deep cycle batt typically benefit from a much more rapid charge, i.e. about 20% of the batt’s capacity, up to as much as 40% for flooded cell batts.

No...the slowest possible charge is always the best charge, for every type of battery. The slower the charge the more sulfation on the plates is allowed to dissolve.

 

[Dunaruna]

Re: A battery question

[colour=blue]Gotta agree with rabbit. If it's close to death, an initial high amp charge may help ressurect it, followed by a steady decrease until trickle.

 

[ZmOz]

Re: A battery question

[colour=blue]Gotta agree with rabbit. If it's close to death, an initial high amp charge may help ressurect it, followed by a steady decrease until trickle.

It might work to fix a dead battery, (though probably not) but as a general charging procedure, 20-40% of capacity is way too much.

 

[LubeDude]

Re: A battery question

This is almost as good as an oil thread!

I just reserected the Battery in the Boss`s boat, it is a deep cycle and it was left bone dead for about a month, with the draw still hooked up. I figured I`d try and save it. He had tried the 10 amp charger on it and it wouldn`t charge. I hooked up a 1.5 amp charger on it and left it. It took about a week for it to charge, but all of a sudden it was full charge. I had it tested and it`s putting out almost 1,000 amps. This would not have happened any other way than slow charging it.

 

[Dunaruna]

Re: A battery question

[colour=blue]

This is almost as good as an oil thread!

I just reserected the Battery in the Boss`s boat, it is a deep cycle and it was left bone dead for about a month, with the draw still hooked up. I figured I`d try and save it. He had tried the 10 amp charger on it and it wouldn`t charge. I hooked up a 1.5 amp charger on it and left it. It took about a week for it to charge, but all of a sudden it was full charge. I had it tested and it`s putting out almost 1,000 amps. This would not have happened any other way than slow charging it.

Interesting senario but with all due respect it ain't that simple.

Some chargers require a reference voltage to excite, in other words the charger won't recognise a dead battery and therfore won't supply amps. Maybe your boss had such a charger.

 

[KRS]

Re: A battery question

First: check the fluid level

Second: shock it with high amps

Third: slow charge it

 

[18rabbit]

Re: A battery question

This is my understanding, yours may differ; in a nutshell, you want to get the sulfur off of the lead plates in the batt asap because it causes irreversible damage. Current flow is what gets the sulfur off of the lead, and the batt soup voltage keeps it off. The more current flowing into the battery, the faster the sulfur comes off, the less damage to the plates. The slower the current, the longer the sulfur stays on the lead, the more irreversible damage there is to the lead plates.

What trickle charging gets you is less heat and that has its advantage, too. Too much heat is also a source of damage for a battery, in addition to being a safety hazard (boom!). The faster you charge a battery, the more heat you generate. Batteries have a spec that indicates the max rate of charge a batt can handle without generating too much internal heat. I think you will find that spec to be between 20% and 40% of a batt’s capacity for a flooded cell battery.

Newer technology resulted in advancing the formulation of the electrolyte to include a catalyst to effect the hydrogen/oxygen bonding inside of a batt with pressure sensitive caps (a VRLA battery). This prevents excessive off-gassing caused by the heat created with higher charging rates. The max rate of charging a battery depends on the batt’s internal resistance. Resistance = heat. AGM’s have very little internal resistance.

AGM batts have advanced to the point that Lifeline claims there is no maximum charging rate for their batteries. From what I have read current ‘in-field’ recommendation suggests limiting the charging of a Lifeline batt to 4-times its capacity (4C); i.e. a 100a/hr batt should not be bulk charged with more than 400amps of current. (I can see Oz gasping for a breath. )

Fwiw, the manf’s recommended charging rate/time table for the batteries on my boat goes up to 2C, or a charge rate that is 2-times the capacity of the battery. They are 130a/hr batts…so 260amps for bulk charging EACH of my AGM batts...not that I have a source for 260amps, but if I did... Above the 2C charge rate the damage caused by the higher rate of charging significantly effects the life of my AMGs.

You should charge your batteries the way that makes you feel the most comfortable. Trickle-heads will want to trickle their batts.

 

[LubeDude]

Re: A battery question

Interesting senario but with all due respect it ain't that simple.

Some chargers require a reference voltage to excite, in other words the charger won't recognise a dead battery and therfore won't supply amps. Maybe your boss had such a charger.

Believe me, when the boss was through it had a good jump, he even had it hooked up to the starting part of the charger for awhile and boiled half the water out.:^

 

[ZmOz]

Re: A battery question

This is my understanding, yours may differ; in a nutshell, you want to get the sulfur off of the lead plates in the batt asap because it causes irreversible damage. Current flow is what gets the sulfur off of the lead, and the batt soup voltage keeps it off. The more current flowing into the battery, the faster the sulfur comes off, the less damage to the plates. The slower the current, the longer the sulfur stays on the lead, the more irreversible damage there is to the lead plates.

Sorry, but you are totally wrong. To remove the sulfation from the plates, you MUST charge slowly. More current will NOT remove the sulfation any faster, it will simply leave much of it behind to harden and ruin your battery. If your battery has enough sulfation, high current can knock it off in chunks, where it falls to the bottom of your battery and short circuits it. It's ruined now. You are right in saying the battery needs to be put on the charger as soon as possible, but that absolutely does not mean it needs to be charged as fast as possible. Once your battery is on the charger, the sulfation is "on pause".

http://zing.ncsl.nist.gov/nist-icv/battery/battery/BatteryCare2.html

Extending the useful life of a battery depends largely upon proper charging techniques. Since sulfation is the number one cause of battery failure, the charging method you choose should be effective in reducing sulfation problems. Rule of thumb: whenever possible, bring any batteries up to full charge as slowly as possible. This slow charging process is also known as equalization. Equalization allows the elctrolyte time to diffuse into the less accessible areas of the plate grid and convert those areas from lead sulfate to active plate material.

AGM batts have advanced to the point that Lifeline claims there is no maximum charging rate for their batteries. From what I have read current ‘in-field’ recommendation suggests limiting the charging of a Lifeline batt to 4-times its capacity (4C); i.e. a 100a/hr batt should not be bulk charged with more than 400amps of current. (I can see Oz gasping for a breath. )

Just because a battery has no, or a very high charge current limit doesn't mean it's a good idea to charge your battery like that. It only means it won't explode. I have several 39AH AGM batteries which I charge at about 210 amps (over 5C) when I'm welding with them, which I know won't give them a long healthy life, but that's what I bought them for. I also keep them on a desulphator when I'm not using them.

The bottom line is, there is not a single reason to charge any battery at more than 1 amp unless you are in a hurry.

 

[Vlad D Impeller]

Re: A battery question

Well i've finally got it back up to full charge, thats according to the old battery charger that i have.
How do i find out what the actual output of this battery is?

 

[18rabbit]

Re: A battery question

Use a voltmeter. A batt starts off with something around 2.2volts per cell, times six cells in a batt = something around 13.2volts. It can be a little higher or a little lower and still be ok.

Oz - you have me thinking about something. I need to call a batt company next week and ask about charging current vs charging voltage and the impact on batts. What I'm thinking is that eq'ing a batt uses low current but high voltage to remove sulfur. I'll post back what I find out.