Charging Voltage for Calcium Batteries

[rogersimms]

To correctly configure a new charger I have bought I need to know what the charging voltage for my batteries are. these batteries are new bought in turkey but have no information on them at all. Would anybody know what the likely charging voltage would be for a 24 volt system for 6 times 105 AH Calcium Batteries (315 AH total)

Thanks

 

[Plevier]

Don't worry about them being called calcium. Lead calcium is not a different type of battery, it's just a lead acid. All conventional wet lead acid batteries have an alloying element to strengthen the lead grids, almost always it's antimony (around 1.5 - 2%) or calcium (I think that's usually about 0.2% but not certain rom memory). Theoretically calcium will accept a sligtly higher voltage without gassing but in practise insignificant. Just set the charger to wet lead acid.
If you actually have to set a voltage, that's a bit more tricky to say without details of the charger (constant voltage or multiple step or what) but 27.5-28V (at 20 deg C) would be a sensible guess if it's on charge for long periods or 29V if it's for recharging occasionally not constant floating.
Mike

 

[Plevier]

Just seen your earlier post and ned to elaborate a bit. Lead antimony batteries used to contain 8-10% antimony years ago and then the difference from calcium in gassing voltage terms wsa significant. Now iwth low antimony content, it isn't.
Mike

 

[rogersimms]

Many Thanks for your replies. Just incase there is any other information regarding these batteries. the charger in question is a victron multi with a 65 amp 4 step charger. at the moment bulk charge is 29 vols. 40 amps absorbtion 27.6/8 lower amps then float at 27.6/8 about 1 amp (could be as much as 24 hours)but after that it then drops to 26.7/8 volts again 0 to 1 amo and that confuses me a bit. The charger is set up for gel batteries and many other and when I contacted merlin for to make sure the settings are all correct they asked for the charging voltage for the batteries

Thanks

 

[Plevier]

Is the charger intended for sealed batteries only? No setting for wet batteries? (Assuming these are indeed wet which I inferred from your first post.)
You could use up to 0.5V lower on stage 4 but I really can't see a problem. If it's left on float for long periods i.e. weeks you may get a bit of water loss I should think just top up occasionally with distilled or deionised water. (Chlorine in tap water is harmful).
Mike