Alternator Charge Voltage Not Enough for Calcium Battery

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Originally Posted by drivesafe

Hi Arthur and which model charger do you have?

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I have two(NOCOs) G7200 and G15000. I primarily use the G15000(15A @ 12v).
Both have the same settings, obviously one at 15A and the other at 7A.

The reason I got the NOCOs is that they also do 24v(at half the amps), and my dads mobility scooter is 24v, and has the XLR plug for him to use easily.

For your quick reference, the repair mode, which I assume is the same as desulphation mode in other chargers.... is rated at 1.5A @ 16.5v.
The AGM+ mode at 15.5v is still rated at 15A.
The 7A model has the same voltages, just at 7.2A instead of 15A

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Originally Posted by lazbaz

Arthur,
Could you send me the url link for this. Thanks

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Sorry lazbaz, I thought I linked the -> LARGE website <- term in my reply, but did it wrongly! So click the link I created in this reply to take you directly to the article I referred too.

Thanks Arthur, the 16.5v is perfect for the wet/flooded and Ca/Ca batteries.

Before you use the AGM+ setting on an AGM, check the manufacturer's website for specific info on a specific AGM battery's maximum voltage.

Some AGMs will tolerate that sort of voltage but MOST WILL NOT.

BTW, when using the 16.5v setting, you should hear and feel the battery boiling.

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Originally Posted by drivesafe

Thanks Arthur, the 16.5v is perfect for the wet/flooded and Ca/Ca batteries.

Before you use the AGM+ setting on an AGM, check the manufacturer's website for specific info on a specific AGM battery's maximum voltage.

Some AGMs will tolerate that sort of voltage but MOST WILL NOT.

BTW, when using the 16.5v setting, you should hear and feel the battery boiling.

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Awesome, info thanks.

I've been thinking to try using AGM+ on the red top in my D2.
For a couple of years now, it's been losing charge rather quickly than it used too.
Setup is redtop as main, and yellow as aux, via a Redarc VSR.
When first hooked up, it used to hold a very high charge, seen by the VSR well into the night and next day .. at a guess, close to two years like that.
Brother parked it up for a good few months, not using D2 and (only) redtop lost charge and must have dropped down to a low level.
Since then, the redtop doesn't hold charge well. After a good long drive where it gets plenty of recharge, the VSR cuts out in only a few seconds now. ie. it won't hold it's normal 12.7v like it used too.

If not trickle charged or used regularly it will lose all it's charge in about 3 days. Overnight it now drops down to 12v .. and confirmed a few times there is not heavy load on it(just a single USB/volt meter, which draws maybe 0.01A or something).
My problem is, that it starts the Td5 with no issue at all, for a battery that is supposedly down to 50% SOH according to the battery analyser .. but it cranks the Td5 like there is nothing wrong!

Totally opposite to my Century in my Tdi .. supposedly 98% SOH, but struggles to crank the tdi in the morning(OK once warmed tho).

According to Optima, the redtop can tolerate 15.6v 'rapid charge'. If I tried AGM+ mode whilst I can keep an eye on it, do you reckon it may help in any way? I can keep an eye on battery temp and stuff like that.

Hi again Arthur and both the Red and Yellowtop should be fine using the AGM+ but if your charge does not have an automatic timeout, you will need to remove the charger if the battery starts to warm up.

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Originally Posted by AK83

My problem is, that it starts the Td5 with no issue at all, for a battery that is supposedly down to 50% SOH according to the battery analyser .. but it cranks the Td5 like there is nothing wrong!

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My last battery replacement was a Supercharge MF88. ~900CCA and ~100AH. It tested fine using a Century battery analyser (> 700CCA) and fine on a carbon pile. Started the car like it did when new. I put it on a discharge test and got a whisker over 20AH. So it still had plenty of grunt, just no endurance.

I've never found a battery analyser that does a credible capacity test, they all seem to assume "lots of amps, must be ok".

The trigger for that was the lad constantly opening the car to "take it for a drive" while we were camping. 2 days of that resulted in a "fail to proceed". A discharge test quickly identified the reason.

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Originally Posted by BradC

I've never found a battery analyser that does a credible capacity test.

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And neither have I.

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Originally Posted by AK83

I have two(NOCOs) G7200 and G15000. I primarily use the G15000(15A @ 12v).
Both have the same settings, obviously one at 15A and the other at 7A.

The reason I got the NOCOs is that they also do 24v(at half the amps), and my dads mobility scooter is 24v, and has the XLR plug for him to use easily.

For your quick reference, the repair mode, which I assume is the same as desulphation mode in other chargers.... is rated at 1.5A @ 16.5v.
The 7A model has the same voltages, just at 7.2A instead of 15A

Sorry lazbaz, I thought I linked the -> LARGE website <- term in my reply, but did it wrongly! So click the link I created in this reply to take you directly to the article I referred too.

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A83,
Are the NOCO chargers suitable to charge Calcium batteries?

Whilst the tester may not be 'accurate' ... it hasn't yet lied about the condition of some of the batteries I have lying around my shed.

Quote:

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Originally Posted by lazbaz

A83,
Are the NOCO chargers suitable to charge Calcium batteries?

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Going by what drivesafe says about the occasional(monthly or so) charge capability of Ca batteries ... I'd say for sure.

But going by what the NOCO's manual says, they reckon just use normal mode(14.5v) for Ca batteries anyhow.
The unit has a 12v(cold)/AGM mode rated for 14.8v if required.

BUT! .. going by all the advise given so far in this thread, I'd say don't fuss too much about having a Ca battery, just treat it as a normal 12v battery.

Also: I can highly recommend the NOCO chargers. They do what they say they're going to do .. and a reminder that primary reason I got my first one(G7200 model) was that it had the ability to charge 24v too, and had the easy to use(for an older person) plug type for a mobility scooter.
Gave it to my father to use it as his primary charger(plus I got him a pair of AGM batteries for it too) .. and I then got a G15000 model NOCO, as it had the quick charge boost mode, handy every now and then, although I have more than enough batteries lying around that I can jump start a dead battery easily enough.

Quote:

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Originally Posted by AK83

Whilst the tester may not be 'accurate' ... it hasn't yet lied about the condition of some of the batteries I have lying around my shed.



Going by what drivesafe says about the occasional(monthly or so) charge capability of Ca batteries ... I'd say for sure.

But going by what the NOCO's manual says, they reckon just use normal mode(14.5v) for Ca batteries anyhow.
The unit has a 12v(cold)/AGM mode rated for 14.8v if required.

BUT! .. going by all the advise given so far in this thread, I'd say don't fuss too much about having a Ca battery, just treat it as a normal 12v battery.

Also: I can highly recommend the NOCO chargers. They do what they say they're going to do .. and a reminder that primary reason I got my first one(G7200 model) was that it had the ability to charge 24v too, and had the easy to use(for an older person) plug type for a mobility scooter.
Gave it to my father to use it as his primary charger(plus I got him a pair of AGM batteries for it too) .. and I then got a G15000 model NOCO, as it had the quick charge boost mode, handy every now and then, although I have more than enough batteries lying around that I can jump start a dead battery easily enough.

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AK83, Arthur,
I bought the NOCO GB40 BOOST PLUS so that I could jump start when I needed to.
Now that I am unsure about my alternator being suitable to charge the battery, I am thinking of G15000 which I could use to charge the battery and keep it in good condition.
So please give me straight answer to my question:
1. Can I plug the charger to the battery terminals while it is still on the car? Do I have to remove the negative connection from the battery to do the charging?
Your answers will be most appreciated.

Quick update on the Optima red top.

As stated before, this battery isn't holding charge well. A few years ago D2 was left sitting for a long time and obviously battery self discharged and has since not really recovered well.
Would go flat(in a TD5) in about 3 or 4 days.. down to about 11.9v and zero ability to crank the TD5.
Sometimes hitting the override/jump start switch I installed for the Redarc VSR would give it just enough help to start, but most times I'd have to pull out the truck battery to manually jump start it.

IIRC the battery tester tool reckoned that the red top was at about 50% SOH/SOC, and CCA rating was down from 800 down to about 600-ish .. but even after a couple of days sitting, cranking was very fast and starting was immediate.
So the red top still had cranking power .. just no endurance.
I use the D2 to commute to work .. easily 30 mins x2, sometimes with traffic the return home could be 1hr .. so I'm not doing any short drives. Red Tops voltage first thing in the morning was very low 12's ... 12.1 usually, a few times 12.2v sitting overnight.

So I used the AGM+(according to NOCO, 15.5v) setting on it on Wed night, left it all day Thu. Got home Thu after work. Battery wasn't hot at all, maybe a few degrees above ambient. Didn't measure it with thermometer, just a hand test. I'd reckon about 20°C at most .. cold day cold battery case too.

Disconnected the NOCO and left battery to settle for an hour or so, maybe two .. dropped down to about 12.5v. Did a test with the battery tool, now comes up at 90% SOH/SOC and CCA rating is just above it's rated 800, at 805. Noting that this was about an hour or two after it's day worth of AGM+ charge.
Now about 12 hrs after the supercharged charge, it's still sitting at 12.4v(actual is 12.42v). Tester reckons that SOH is 93% SOC is 88%(ie. same 90% figures as before).

So like drivesafe says .. occasional zapping with the high voltage modes on the charger seems to help.

While it's going to be cold outside for a few days, I'll give it another zapping again to see if will recover a bit more.

Side note: the yellow top seems to be totally fine. It dropped a bit(didn't test it tho) .. and I gave it a small charge during the week the D2 has been sitting. Probably didn't need it, but why not. Through all of this it's basically held 12.7v with no trouble.