SLA discharge question

[smokydays]

Assuming that a smart charger was used to charge them, how many cycles could one expect from a SLA battery if only discharging say to 50 to 60% full charge?

Also what would be the difference in running it down from 10 to 0%?  How many cycles could one possibly expect?  I know this number will be lower but i have no idea what it would be.  Any ideas?


EDIT: to fixie de englaise

[smokydays]

Might have answered my own question, found this article:

http://www.buchmann.ca/Article4-Page1.asp

From the article:
"Depending on the depth of discharge and operating temperature, the SLA provides 200 to 300 discharge/ charge cycles. The primary reason for its relatively short cycle life is grid corrosion of the positive electrode, depletion of the active material and expansion of the positive plates. These changes are most prevalent at higher operating temperatures. Cycling does not prevent or reverse the trend."

So you think i could expect to get 50 - 100 deep discharges in this case?

[F.O.Bean]

i would not deep discharge sla's

i carry NIMH rc batts now adays, quick charge times and high mah capacity

[smokydays]

Yea i agree with ya, the NIMH would be the best solution.  Thing is i already have two old APC UPS power supplies that I am not using and they happen to each have a 7200ma 12v battery in them.  I would only be using them a few times per year, so if they would last 50 deep discharges that would be plenty.  I plan on powering my motu traveler and laptop in the field with the 2ea 7200ah batts.  I just found a 12v car adapter for my laptop.  I figure it will give me about maybe 3 hours runtime with the sla's and the laptop's fully charged internal battery.  Festival type situations i could throw a 18000ma sla in the mix.

[momule]

I have (4) 12v 4Ah and (2) 12v 7Ah that your more than welcome too at any time Dan .

[Burnt]

I would only be using them a few times per year, so if they would last 50 deep discharges that would be plenty. 

It's not a good idea to deep discharge SLA batteries, you'll damage them that way.  Just charge them up the night before you use them and NEVER discharge them because they have no memory effect.

[F.O.Bean]

I would only be using them a few times per year, so if they would last 50 deep discharges that would be plenty. 

It's not a good idea to deep discharge SLA batteries, you'll damage them that way.  Just charge them up the night before you use them and NEVER discharge them because they have no memory effect.

the nice thing about sla's is, you can let the float for an eternity, i let mine sit w/ my eco charger ALWAYS pluigged in, that way theyre always 100% when you need them

[smokydays]

I have (4) 12v 4Ah and (2) 12v 7Ah that your more than welcome too at any time Dan .

Thanks Nick, appreciate that!

It's not a good idea to deep discharge SLA batteries, you'll damage them that way.  Just charge them up the night before you use them and NEVER discharge them because they have no memory effect.

Yeah, I am sure that it will decrease the overall life of the batteries, but that is an acceptable risk in this case (i already have them and dont use them anyway).

the nice thing about sla's is, you can let the float for an eternity, i let mine sit w/ my eco charger ALWAYS pluigged in, that way theyre always 100% when you need them

Yep, I have them just sitting in the UPS unit charging as we speak.  That's a nice advantage of sla's.

+T's everyone, thanks for the responses.