Two Types of AGM batteries?

[camaraderie]

Extemp...
Your Magnum Energy Chart for Lifelines calls for 14.3V Absorbtion and 13.1 V float for Lifeline.
Lifelines site calls for the following:
Bulk/Absorb 14.4 - 14.8(14.6 midpt) Float 13.4 - 13.6(13.5 midpt)

The link should you wish to review it is:
Lifeline Batteries - Marine & RV Deep Cycle Batteries

Hope that qualifies my response.
As to reading the English Guys e-mail...I did and quite thoroughly and I believe HS has just trashed his opinions further and quite appropriately.

[Extemporaneous]

Originally Posted by camaraderie

Extemp...
Your Magnum Energy Chart for Lifelines calls for 14.3V Absorbtion and 13.1 V float for Lifeline.
Lifelines site calls for the following:
Bulk/Absorb 14.4 - 14.8(14.6 midpt) Float 13.4 - 13.6(13.5 midpt)

The link should you wish to review it is:
Lifeline Batteries - Marine & RV Deep Cycle Batteries

Hope that qualifies my response.
As to reading the English Guys e-mail...I did and quite thoroughly and I believe HS has just trashed his opinions further and quite appropriately.

1. The company you quote with the picture chart has TOP of the line inverter chargers ME series...that have ONE setting for ALL AGM batteries.

For miss information that is.
I went searching for the source of my miss information and found it.
See: Lifeline AGM Batteries Charging Procedure
And so ..... your right and I'm wrong, thanks for catching that.
As for the trashing of the English Guys e-mail, there seams to be consensus and it would NEVER have been my approach.
Regarding the ME series (Modified Sine Wave), it would appear that their one setting (without the remote) is wrong (14.3v). I have the MS series (Pure Sine Wave) Charger/Inverter and the ME-RC remote (which is used for both the MS and ME series). Once you have the remote you have available, the settings as per the attachment (not mine, Magnum Energy's) in my previous post.
Strange that a company like Magnum Energy has this wrong. Kinda makes me wonder if Lifeline changed their spec's/tune sometime in the past.
I'll have to send them an email.

Now, can you automate Amp-hour law charging for me?

Regards,
Extemp.

[Therapy]

Originally Posted by Extemporaneous

For miss information that is.
I went searching for the source of my miss information and found it.
See: Lifeline AGM Batteries Charging Procedure
And so ..... your right and I'm wrong, thanks for catching that.
As for the trashing of the English Guys e-mail, there seams to be consensus and it would NEVER have been my approach.
Regarding the ME series (Modified Sine Wave), it would appear that their one setting (without the remote) is wrong (14.3v). I have the MS series (Pure Sine Wave) Charger/Inverter and the ME-RC remote (which is used for both the MS and ME series). Once you have the remote you have available, the settings as per the attachment (not mine, Magnum Energy's) in my previous post.
Strange that a company like Magnum Energy has this wrong. Kinda makes me wonder if Lifeline changed their spec's/tune sometime in the past.
I'll have to send them an email.

Now, can you automate Amp-hour law charging for me?

Regards,
Extemp.

I am trying to learn some of this stuff but the chart below this:

The open circuit voltages listed below approximates the various States of Charge (SOC

Makes me realize that I don't know squat.
If it is open circuit for 4 hrs and one measures voltage what does the columns for rate have to do with it? Do you have to know what you did last? Read a book or raise the anchor?????

[Rick]

With the advent of good battery monitors one never needs to know or attempt to measure a standing voltage to infer state of charge. One REALLY wants to know state of capacity anyway, not state of charge. So, use a real monitor and forget haveing to discover standing volage.

[Extemporaneous]

Originally Posted by camaraderie

Extemp...
Your Magnum Energy Chart for Lifelines calls for 14.3V Absorbtion and 13.1 V float for Lifeline.
Lifelines site calls for the following:
Bulk/Absorb 14.4 - 14.8(14.6 midpt) Float 13.4 - 13.6(13.5 midpt)

The link should you wish to review it is:
Lifeline Batteries - Marine & RV Deep Cycle Batteries

I thought I had seen more or different info from Lifeline then what your link showed.

It would appear that Lifeline can't makeup their own mind as to how to treat their own batteries.
http://www.lifelinebatteries.com/manual.pdf
Check out page 16 (Table 5-1). Before that table they say "The second stage is often called the Absorption charging stage. A voltage limit of 14.4 volts +- 0.1 volts should be used when the battery temperature is 77F (25C).". If you assume that they used the word "limit" properly it would suggest that Magnum Energy is closer then Lifeline's other literature. If the pdf manual is indeed the correct Lifeline literature. It also says 13.26 volts for a float charge. You'd think they would have that straight at least!
It's hard to speak with conviction (at least for me) when you are just a user and rely on others for the truth, that is unless you are someone like Rick and have the experience to back up your statements.

Now the above doesn't really matter, if I understand Rick correctly.

I just wanted to point out a good example of how misinformation happens.

Regards,
Extemp.

[hellosailor]

"So, use a real monitor "
Rick, what do you consider a real monitor? And, just how expensive are they?

[Rick]

A real battery monitor (for 12V case given here) has internal current measurement stability better than 50mA (do not confuse stability with resolution) over 24 hours and over a wide temperature range. It has at least 100mA resolution displayed. The voltage resolution is at least 100mV. It can simultaneously measure the voltage and current so that voltage and current spikes do not fool Amp-hour and kilo-Watt-hour measurements. Kilo-Watt-hour measurments are necessary (even if not displayed) in order to determine that a battery has had discharged capacity returned when charged.

The voltage burden of the shunt should not be more than 50mV for 500A else the loss is too great for an inverter system.

I know that the Link series of monitors meet these (and other) parameters. Others may as well. The Link 10 is probably the lowest cost...they have been sold for less than $100 new. I think that $150 is a higher cost from some sources.

Some of the monitors which use Hall-effect devices for current measurement instead of a shunt do not have good stability and long-term drift accuracy to say nothing of aperture inaccuracy. Something to check.

I would say that long term current stability is where most non-"real" monitors fall down. With poor long term current stability one accumulates excessive Amp-hour gains/losses which are not real.

[Therapy]

Originally Posted by Rick

I know that the Link series of monitors meet these (and other) parameters.
.

Thank goodness,

I am feeling better now.

Now, it was just programmed correctly.

Thanks for all the info guys.

[Extemporaneous]

Originally Posted by Rick

Having spent 30 years working with batteries, designing charging systems and battery monitors AND referring to electrochemistry textbooks and technical papers regarding lead-acid batteries (yes, AGM's of all types and gel-cell are still lead-acid) it is evident that there is NO set battery charged voltage that is "correct" with the exception of float voltage (specified at a specific temperature).

MY past posts describe just how fast one can charge a battery and there are various discussions regarding the so-called "Amp-hour law" taken from electochemistry texts. The three-step charging algorithm is a first appoximation to the Amp-hour charging method and CAN be exceeded.

Here is a short description of charging: Float voltage is determined by the designed acid concentration and temperature period. There is a simple formula describing the at-rest cell voltage as a function of the specific gravity of the electrolyte. ALL AGM batteries follow this as well. With ANY lead-acid battery of any type use for deep-discharge high current applications You can safely charge the battery without excessive temperature rise or gassing by applying a charge current equal to (or slightly greater than..following my experience) the value of Amp-hours "missing" from the battery. This concept cuts through all of the crap regarding charge voltage because the voltage is always different as the battery comes up to full.

Now when the three-step method was first promulgated by Ample Power and then by Cruising Equipment and then implemented by Heart Interface (with their inverter/chargers) it was with the realization that simple voltage regulation in steps could approximate the Amp-hour law. We all wished early on that it was affordable to create a charger to exactly follow the Amp-hour law yet knew that a battery monitor would have to be married both to the battery as well as the charger to do that.

One observation that I have made is that the beginning charge voltage of the Amp-hour law charger would always be higher than 14.4V and usually below 15Volts. Does that give anyone a clue? It makes no difference weather one is using an AGM with a specific gravity requiring a float voltage of 13.2 Volts or one requiring a float voltgage of 13.9 or 14.0 Volts. Gel-cell batteries love this as well and tended to "look" more like the bettery quality AGM's like Fullriver today. Again, do not confuse float voltage with upper limit acceptance voltages that would keep charge current within the limit of the number of amp-hours missing from the battery as stated.

Hope that this helps cut through the crap regarding all the different acceptance or equalization misinformation out there.
Rick

Rick,
I think I've read most of your posts on batteries, however, still end up with questions.

• I think I understand that you are saying float voltage values are a strict product of battery chemistry and temperature.
• I understand that one can charge one's batteries with an amperage equal to what is missing from the batteries.

What hasn't been made simple enough for me is the voltage part of Amp-hour law charging (besides float voltage). I guess some battery manufactures publish this, but more generically would it be a temperature right before gassing?
And so in theory, the charge voltage would be as high as possible but below the gassing state. Is this "upper limit acceptance voltages"? And the Amperage would always be equal to the amount of Amp hours which need to be replaced?

If that's not it, could you explain the relationship (in another way if you already have, because I didn't get it).

Thanks,
Extemp.

[Rick]

The voltage is irrelevant when Amp-hour-law charging because it is (as you stated, "the Amperage would always be equal to the amount of Amp hours which need to be replaced". Current charging, even in this case which is varied, has what is called a compliance voltage, an upper limit which when reached, limits the current as well.

A good "upper-end" compliance voltage is about 15V for Amp-hour law charging. On the other hand for flooded-cell batteries an upper end compliance voltage can exceed 17Volts when using an equalization cycle.

So, is it more clear that voltage is essentially irrelevant when charging if the charge current equals the missing number of Amp-hours? ONLY float voltage is important and regulated.

If one follows the Amp-hour law gassing potential is not reached at a significant value until it is necessary to float. Keep in mind that gassing potential is a function of how full is the battery. Gassing potential changes as a function of the state of charge. This is easy to understand if you realize that gassing potential varies as does the specific gravity. Specific gravity increases as the battery is charged and the gassing potential drops.

When the battery is full the gassing potential will be just above the float voltage. When the battery is empty the gassing potential will be above 15V.

[Extemporaneous]

Originally Posted by Extemporaneous

I thought I had seen more or different info from Lifeline then what your link showed.

It would appear that Lifeline can't makeup their own mind as to how to treat their own batteries.
http://www.lifelinebatteries.com/manual.pdf
Check out page 16 (Table 5-1). Before that table they say "The second stage is often called the Absorption charging stage. A voltage limit of 14.4 volts +- 0.1 volts should be used when the battery temperature is 77F (25C).". If you assume that they used the word "limit" properly it would suggest that Magnum Energy is closer then Lifeline's other literature. If the pdf manual is indeed the correct Lifeline literature. It also says 13.26 volts for a float charge. You'd think they would have that straight at least!
It's hard to speak with conviction (at least for me) when you are just a user and rely on others for the truth, that is unless you are someone like Rick and have the experience to back up your statements.

Now the above doesn't really matter, if I understand Rick correctly.

I just wanted to point out a good example of how misinformation happens.

Regards,
Extemp.

And someone else who figures Lifeline changed their numbers.

Originally Posted by senormechanico

FWIW, here is a page from Lifeline batteries. They have modified their previous numbers.

Lifeline Batteries - Marine & RV Deep Cycle Batteries

Steve B.