
bret.tallent
USA
Asked
— Edited
I have purchased this battery for my B9 hack, it is 6V 12AH.
It is an SLA and for charging instructions it says:
Standby use - 6.75 - 6.9V
Cycle use - 7.2 - 7.4V
Initial current - max 0.3CA
My question is, what do I need for a charger? The one I have for my Omnibot is a 6V 500mA charger. Will this work with this battery?
Thanks,
Bret
A 7.2v 300mha is what you'll need
The charge rate (indicated by ca) is multiplied by capacity. So .3 x 12ah is 3.6 Amp max charge rate. At this rate your battery will be fully charged in about 3.5 hours. At a rate 300 mah your battery would go from dead to full charge in 40 hours. That would take forever so for this battery , a larger charger would be in order lol. You may want to just go to walmart and get a 2ah smart charger for motorcycles and you can charge your battery from dead to max in a little over 6 hours. And a smart charger automatically switches to a lower floating voltage once your battery is full ;D. My charger was a atv/moto charger in auto section.
- Josh
It's 21 dollars and you have it now
Try this :
http://www.tecmate-int.com/ENG/u_accuguard_900.php
Ecellent product for a reasonable price. I have several. Easy to use and automatic. Max current depending on your model = 1.8 Amp
This :
http://www.ctekbatterychargers.com.au/ctek-mxs25.html
is even better (fast charge etc...) but needs to be controlled by hand. I mean, you must select
the charge mode and press a start button. Not always handy. It's a little more expensive but also
capable of higher capacity batteries. Quite good !
And finally this :
http://www.vellemanusa.com/products/view/?id=350613
Build it your own ! It's a good product and gives you the opportunity to customize it to your own needs. However, the first charger from 'tecmate' is probably cheaper.
Good luck with it.
SLA batteries especially, need a charger that will automaticaly decrease the charge rate as the battery approaches full. When a battery is empty it'll suck-up many amps no problem, but the closer it gets to full the less it's eager to suck-up those amps, and the excess becomes heat. Heat evaporates your electrolyte, slowly at first, but can become a full on boil if you forget about it. On older style flooded batteries this isn't an issue (and in fact, a good boil is sometimes beneficial on occasion), because they are basicly open topped & very easily refillable. But on SLA batteries, there's a safety vent to release excess pressure from evaporating electrolyte (some do feature a chamber that holds onto the gas, to let it condense back into the battery later, but they only hold so much before again venting comes into play), but no way to refill it, so once it's gone it's gone. In severe cases, you can actually cause an SLA battery pop wide open (I've had it happen in my computer's UPS and my wheelchair), which creates a lovely cloud of sulfuric acid gas until you figure it out & disconnect the charger.
Take care of your batteries & they'll reward you with a long life, abuse them & you'll quickly need new ones.
Mel