Calcium - calcium batteries

[Tricia]

I need help!

I have a calcium - calcium battery on my boat that doesn't seem to accept a charge. When I bought the battery, the shop put it on charge for 24 hours (at my insistance), but the battery was only showing 50% charge the next day. I asked them to keep it on charge for a further 24 hours at which point it showed 100% charge. However, since installed in the boat it won't go over 70% charge. I have been told that calcium batteries are maintenance free, but this one doesn't seem to be. It is a 135ah battery.

Does anyone know anything about calcium batteries ie: charge rates, topping liquid and manufactures (the manufacturer on my battery is Texet, but I can't find a contact number or web address for them).

 

[2Tizwoz]

'However, lead/calcium batteries are not very resistant to "deep-cycling" (deep discharge followed by a full charge). This made them inappropriate for uses such as to power trolling motors in fishing boats. It also required a higher charging voltage. General Motors studied the charging characteristics of lead/calcium batteries and set the voltage regulators of cars equipped with the "Delco Freedom II" battery at 14.8 volts. Lower settings prevented charging to full capacity. This is too high for lead/antimony batteries and will cause them to lose water rapidly.' Quoted from this site

 

[alan17]

I believe that calcium batteries require a different charging regime that can only really be achieved using a special charger. Basically the required regime is a pulse charge.

 

[William_H]

I have never herd of Calcium batteries before but from 2Tizwoz reference it sounds like a variation on basic lead acid battery.
How do you know if it is fully charged?
I am guessing that you are using a regulated possibly step charged battery charger which from the reference may not be regulating at a high enough voltage and may also be telling you it is not fully charged.
Terminal voltage or even Specific Gravity of the electrolyte are not always a reliable way to determine if a battery is fully charged. In fact the only reliable way is to discharge the battery to find out how much current you can get out of it and so how well charged it is. but that is not practical or a good idea.
I would suggest that you ensure the battery is fully charged by using a current limtied charger. That is one of the old style chargers that have just an ampmeter to indicate current. The voltage provided is in the form of a rising pulse to a relatively high voltage that then diminishes to zero and repeats at 50 or 100 times per second from the mains AC. The higher (17 volts) voltage peak pushes more current in for a short period the current being limited by the internal resistance of the transformer or a resistor. The average current is what matters and is indicated by the inertia of the needle of the meter. This is the most crude of old fashioned chargers but works very well provided you are willing to remember to turn it off. ie the only disadvantage is it is not automatic. (the charger is a simple transformer with bridge or half wave rectifier with if necessary a series resistor for current limiting and an analogue mechanical amp meter)

You can put 135 amp hours into the battery if this is done at a relatively low current say 2 amps then no harm can be done by overcharging. Then you know it is fully charged. After leaving settle for some hours you can check the terminal voltage to get a reference fully charged voltage.
From here you will have to trust that it is a good battery and service experience will show if it does the job you need.

To paraphrase I think you have been fooled by the indications of an automatic charger as to its charge status. From the reference it may need a higher regulated charging voltage. good luck olewill

 

[Tricia]

Thanks, only problem is that I'm not on mains as wintering in Prevesa Greece and no mains on the pontoon, but no charge so not all bad.

Some of us have a hard life ;-)