Please review these battery readings.

It’s an aluminum boat.

I have the caps off the battery and connected directly.
In this case, for some reason, if you read the ProLogix instructions, it essentially says: if there is no chassis ground, connect one leg of a set of jumper cables to the negative terminal, and connect the ProLogix clamp at the other end to complete the circuit.

Not sure why exactly, must be something about the increased resistance from the longer cable run?
 
What we don’t know is if the charger tried to get the voltage up higher, which would imply a higher current charge.

Should be seeing >14v when it’s pushing in full 12hr time lapse doesn’t really indicate if this is the case.

You had a depleted battery, it could need nearly 100Ah to charge. Sitting on a charger at 10A for 12 hours in theory would get you there, but if it couldn’t push 10A in then it could take much longer. It’s likely that the charger pulled back current and the battery resistance is higher, so it’s just charging slowly. That may not matter for your use.

Well it was on 10a all night.

Looked this morning and it was showing Error and the charging in progress light was flashing.
8:54am
0%
11.5v

Put it back on 10a and it immediately started climbing for v.

9:15am
38% and 13.3v

11am
43%
13.2v

Each cell is slowly "bubbling" except for the one cell I mentioned earlier, the one towards the boat's V-hull, meaning it was leaning in that direction and the cell was low and "muddy" looking. Added water to that cell and one other.
 
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Start battery shopping.

Using a tender from a very low state of charge is unideal.

Flood 12v Marine batteries are not built nearly as well as a true deep cycle lead acid battery, but there are few actual flooded 12v deep cycle batteries available, and they are not in the group 24/27/29/31 size ranges.

But you got 6 years from it, it owes you nothing, and you can treat the next one similar and expect similar results.

Judging battery remaining ability is going to require tools and time.
judging battery by what some so called smart charger is doing, leaves far too much room for inexperienced interpretation.

'One muddy cell' says it all.
Its probably the one closest to negative terminal, and likely has a specific gravity far below the 5 others, and no magically marketed charger is going to reverse it.

A good charger can slow capacity loss with accumulated cycles, but is not going to magically restore performance to an older wornnout or abused battery, no matter what its literature, or fan boys claim.
 
A good charger can slow capacity loss with accumulated cycles, but is not going to magically restore performance to an older wornnout or abused battery, no matter what its literature, or fan boys claim.
So you’re claiming that my ProLogix bringing back an Interstate that read 11.1V and wouldn’t even turn on interior lights 3 years ago, spent 24 hours on the 2310 and started just fine the next day. That battery is still alive and working fine is a figment of my imagination? 🤣

Not saying ProLogix will save OP’s battery or every battery, but there’s plenty of evidence contrary to your opinion.
 
Bought one of those small bulb type testers with floating balls.

Acid was HOT.

Five cells: four (all) balls floated.
The low cell: zero balls.

Time for new battery.

Thanks for the entertainment. I mean advice.
 
Bought one of those small bulb type testers with floating balls.

Acid was HOT.

Five cells: four (all) balls floated.
The low cell: zero balls.

Time for new battery.

Thanks for the entertainment. I mean advice.
You need an actual SG meter, 1.27 on all cells is what you're looking for.

Probably "hot" because you have a nearly dead cell but the idiot battery charger can't tell that and just keeps pouring the coals to the other cells trying to get the total voltage to 14.4
Don't even leave a suspect battery hooked to a charger all night. If you have the right charger for the battery, 4 hours will charge anything.
 
You need an actual SG meter, 1.27 on all cells is what you're looking for.

Probably "hot" because you have a nearly dead cell but the idiot battery charger can't tell that and just keeps pouring the coals to the other cells trying to get the total voltage to 14.4
Don't even leave a suspect battery hooked to a charger all night. If you have the right charger for the battery, 4 hours will charge anything.

Zero balls floating tells me dead cell. Dead AF.
Why do I need a fancy meter for THIS dead battery???
 
So you’re claiming that my ProLogix bringing back an Interstate that read 11.1V and wouldn’t even turn on interior lights 3 years ago, spent 24 hours on the 2310 and started just fine the next day. That battery is still alive and working fine is a figment of my imagination? 🤣

Not saying ProLogix will save OP’s battery or every battery, but there’s plenty of evidence contrary to your opinion.
I can take the worlds cheapest 12v flooded lead acid battery, draw it down to 11.1v over 10 hours, put it on any just about any C10 charger for 14 hours, about 100 times back to back, before it might be worn enough to be in danger of not starting a modern fuel injected engine.

A marine battery woukd likely do it 200 to 250 times.

You did it once 3 years ago, and use it as proof of the magical properties of bitog's most recommended charger's ability to defy physics.

Now if you said the baTtery was 3 years old, then allowed to drain to 11.1v over 6 months, and charger x did nothing when applied for 14 hours, and charger Y also did nothing, but charger B did, and the battery is still 'going strong' 3 years later, then id probably say charger X and Y are simply junk, and remain unimpressed.

Im not saying it is a bad charger, im saying beware of Marketing and half pictures. Any charging source capable of bringing an undercharged battery to, and holding it in the mid 14's is doing something good for the battery.

Those chargers with 'recondition' features, which will extend the time held at ~14.4v, then rIse voltage towards the mid 15's, stand a better chance of dissolving hardened sulfaTion, and restoring some nknown portion of lost capacity and performance, but this intended forced overcharge is also stressful on a battery when it is performed when not required.

If the OP were so inclined, intending to use the trolling motor often and hard and wanting maximum battery longevity, then a good temperature compensating hydrometer would be a wise , but frustrating investment.

Frustrating, as it would become obvious that achieving 1.270 or higher after each deep cycle, the true measure of true full charge, would require loading the battery, dropping lits surface charge voltage below 12.6, and then restarting the charger over and over is required to achieve 1.270+.

Been there, done that, and now use adjustable voltage power supplies to hold absorption voltage for as long as the tools amd long experience tell me to.

And 80% charged to 100% charged is never less than 3.5 hours, amd that is with a newish healthy battery held in the mid 14s that entire time.

Older batteries and lower charge voltages will extend that time from 80% to a true 100% considerably.

A 30% charged healthy baTtery will have no issues staRting a fuel injected engine.

I know most assume if the battery starts the engine, it is 100% charged and 'still going strong'.
Both can be measured tested, and verified, but few have ever bothered.

Im bowing out of all lead acid battery /charger threads, because it is akin to peeing into the wind and then finding someone hiding behind a tree upwind, wants to throw their feces at me too.
 
If the battery is mounted at an odd angle causing fluid loss, I would suggest looking into an AGM deep cycle battery. That is one advantage of AGM. Duracell, East Penn, NAPA and Optima make them
 
In this case, for some reason, if you read the ProLogix instructions, it essentially says: if there is no chassis ground, connect one leg of a set of jumper cables to the negative terminal, and connect the ProLogix clamp at the other end to complete the circuit.

Not sure why exactly, must be something about the increased resistance from the longer cable run?
No, the purpose it to make the final connection as far away from the battery as is reasonably possible to prevent a spark near the battery.
Its mentioned in each section to not connect directly to the battery and to use a chassis ground or the booster cable to prevent sparks near the battery.
 
I guess I want to be abused. This battery good to go for trolling?

My buddy said to stop overthinking it. He has even used car batteries to power his trolling motor. Whatever.

I have read the website for my Minnkota 55 Endura max trolling motor. It clearly states that if your battery is rated in CCA or MCA, then it’s not a “true deep cycle”

This is the new battery I have.


And yes I am charging at 10a

image.jpg
 
Is a one year free replacement warranty typical for a deep cycle battery? Three to four years for starting batteries.
 
So yes, it's true, a "marine deep cycle" battery is basically just a regular starting battery. Somewhere on the interwebs there's a guy who dissected both (that is, a regular starting battery and a "marine deep cycle" battery both of the same BCI group and both from the same manufacturer) and they were basically identical. He also compared them to a "true" golf cart GC2 deep cycle and the difference was obvious.

However.... does that mean you can't use a 24DC to power a trolling motor?? Of course not. in fact, I would probably choose the marine deep cycle because it's "maintenance free"... the "true" deep cycle units need to be maintained --- that is, you need to watch the water levels and top them up every so often... and lets face it, nobody's going to do that.... and so you are better off with the starting battery.

And this is what I do with my own back up power sources. many years ago I used GC2s, but they needed constant attention, and sure enough I lost track (kids got in the way) and they died. that was 2010. Ever since I've used "marine deep cycle" and they have lasted about 8yrs. the set I bought in 2014 is just now on its way out, and I never had to add water.
 
So yes, it's true, a "marine deep cycle" battery is basically just a regular starting battery. Somewhere on the interwebs there's a guy who dissected both (that is, a regular starting battery and a "marine deep cycle" battery both of the same BCI group and both from the same manufacturer) and they were basically identical. He also compared them to a "true" golf cart GC2 deep cycle and the difference was obvious.

However.... does that mean you can't use a 24DC to power a trolling motor?? Of course not. in fact, I would probably choose the marine deep cycle because it's "maintenance free"... the "true" deep cycle units need to be maintained --- that is, you need to watch the water levels and top them up every so often... and lets face it, nobody's going to do that.... and so you are better off with the starting battery.

And this is what I do with my own back up power sources. many years ago I used GC2s, but they needed constant attention, and sure enough I lost track (kids got in the way) and they died. that was 2010. Ever since I've used "marine deep cycle" and they have lasted about 8yrs. the set I bought in 2014 is just now on its way out, and I never had to add water.

Interesting.

And when I posted above, the interstate, marine deep cycle, has Cavs to pop off I’m assuming to ensure you can add water which I did. We came home tonight after a fishing trip, 77% and 12.5 V.

Is there really a reason I can’t plug it into a 0.75 amp or a two amp charger?

I have it on the 10 amp right now but just wondering why would it be “bad” to do so as long as I use the 10a every few trips.
 
Are these chargers automatic ones that will not overcharge, then yes to any one of them as they will not overcharge or cook the batteries.
I would use the 10a if going back out the next day otherwise I prefer to slow charge them with the smaller chargers.
Monitoring the battery and chargers with a voltmeter will give you an idea of how each one performs.
 
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