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Voltage Reading of A New SLA Battery

Voltage Reading of A New SLA Battery

Voltage Reading of A New SLA Battery

(OP)
I have read in several places that a new SLA battery is shipped completely discharged but there is never any indication of what the voltage reading would be if measured in that state. I assume the battery chemistry would produce some measurable open circuit voltage even if it could not support any meaningful load. Does anyone have some idea what the open circuit voltage would be for a new never charged 12V SLA battery?

RE: Voltage Reading of A New SLA Battery

Around 12V is dead for all useful purposes. I have never heard that SLA batteries are shipped in this state. I can't even imagine it. Modern SLA batteries take a VERY dim view of the discharged state. With blinding speed they sulfate their plates giving away the bulk of their capacity when discharged. I've seen new SLAs that were rendered useless by being discharged to just below 12V and left for less than 2 hours before re-charging. They lost 95% of their capacity - permanently. Complete write-offs.

I'd not buy SLAs from anyone supplying them "dead".

Keith Cress
kcress - http://www.flaminsystems.com

RE: Voltage Reading of A New SLA Battery

(OP)
Thanks for replying and it appears I must have misread something as I tried to search again for that reference on how new SLA batteries are shipped and could not find it. My error. The full story is that I received batteries that were scuffed on the bottom more than I thought they should be scuffed for new batteries and the terminals had scratches that appeared to be from metal to metal contact and not from the plastic terminal covers. I measured the voltage as they came out of the box and was trying to find out the typical voltage one might expect on new batteries. The good news is that while I was searching for that reference I found a chart the referenced voltage versus state of charge and the batteries as received appeared to be at 90% of a full charge. That could be very typical for fully charged battery that sat idle for several months. At this point I guess the only thing I can do is use them and see how long they last. Two previous batteries went 3 1/2 years each.

My apologies for taking up your time.

RE: Voltage Reading of A New SLA Battery

No problem at all. Glad you came back with more info.

Flooded non-sealed batteries often come unfilled or "dry charged". They often need to be charged for use and have low cell voltages initially but not SLAs.

Cheers.

Keith Cress
kcress - http://www.flaminsystems.com

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