Charging concerns

[o1marc]

I have a new Schumacher charger that charges at 30a. With 4 GC2's, if I leave the charger on over night it should charge and be in "maintain" mode. But it says "bad bat F03". Manual says this is due to "the battery not reaching "full charge" voltage. May be caused by trying to charge too large of a bank on too low of a current setting or have the battery checked or replaced." How much is too much amperage to charge batteries at? On my old charger It had a 3a, 10a, and a 50a start mode. The start mode only kicked in when it was on 10a and you hit the starter it would sense the load and bump the charge. I just realized on my new charger I can select 85a charge.

[kazetsukai]

Originally Posted by o1marc

How much is too much amperage to charge batteries at?

This would depend on the battery. Do you have the spec sheet for them? It should say charge/discharge ratings.

[o1marc]

Originally Posted by kazetsukai

This would depend on the battery. Do you have the spec sheet for them? It should say charge/discharge ratings.

Don't have a spec sheet, only numbers I find are RC@25amps- 447hrs, amp hours at 20 hrs.-224ah.

[kazetsukai]

Hmm, perhaps with the model number I could look them up? What is the chemistry/configuration?

[o1marc]

Originally Posted by kazetsukai

Hmm, perhaps with the model number I could look them up? What is the chemistry/configuration?

Interstate GC2 golf cart battery.

[brokedown]

Lots of specific models under that GC2 name but according to this site (INTERSTATE DEEP CYCLE BATTERIES CHARGING RECOMMENDATION) they are all C/10 which is amp hour rating divided by 10. So if it's 224AH the maximum charge rate would be 22.4A. If you've got them 2x2 for 448AH @12v then 44.8A max charge rate.

[o1marc]

Originally Posted by brokedown

lots of specific models under that gc2 name but according to this site (interstate deep cycle batteries charging recommendation) they are all c/10 which is amp hour rating divided by 10. So if it's 224ah the maximum charge rate would be 22.4a. If you've got them 2x2 for 448ah @12v then 44.8a max charge rate.

9-gcu-utl....


If that's the case, how do I fully charge them if 30a doesn't do it and 85a is too much. I've had it on 85 a for about an hour now and it definitely charged them up to 13.4, 95%. and it showed "RDY". But was still charging and not in "maintainer" mode.

[kazetsukai]

Originally Posted by brokedown

Lots of specific models under that GC2 name but according to this site (INTERSTATE DEEP CYCLE BATTERIES CHARGING RECOMMENDATION) they are all C/10 which is amp hour rating divided by 10. So if it's 224AH the maximum charge rate would be 22.4A. If you've got them 2x2 for 448AH @12v then 44.8A max charge rate.

^^^ Something like this may give you a good estimate for your bank:

https://power-calculation.com/batter...calculator.php

"Voltage of one battery": 6V
"C-Rate" should be 0.10
Plugin your bank details: parallel/series/etc

[o1marc]

They are 2x2 for 12v.

[kazetsukai]

Originally Posted by o1marc

They are 2x2 for 12v.

The calculator at 1/10C is suggesting 42A.




If that's right, those batteries have quite a bit of a resistance... maybe I'm just spoiled with lithium, then again I have other concerns like, if I ever short +/- I'm looking at a discharge in excess of 500A. For sippy loads they're probably alot of bang for the buck.

[john61ct]

I am so confused by this thread.

The amps rate is irrelevant in this case other than how long it should take.

Either the battery or the charger is faulty or broken.

If this is a deep cycling application, you should be buying better quality of both.