Society of Robots - Robot Forum
Electronics => Electronics => Topic started by: Bobsta on October 28, 2010, 04:52:46 PM
-
O.P.
Hey guys,
I got these two 12v batteries somewhere and currently use them to power a portable sound system.. but after a good 4 days of power, I've managed to juice them dry.. I've looked up on the net how to re-charge them but I'm a little confused.
Details:
Vision
CP 12120 12v 12AH
Valve Regulated
Rechargeable Battery
Constant voltage charge
Cycle Use: 14.5-12.9v
Standby Use: 13.6-13.8v
Initial Current: Less than 4.9A
How would I go about 'trickle' charging this?
I know a little about electronics, but since I don't want to mess these bad boys up.. I was hoping you could dumb it down a bit for me :)
(Was also hoping to say modify a phone charger or similar transformer to charge it, instead of buying a charger for it.)
- Andy
-
Google says http://autospeed.com/cms/title_Zero-Cost-Trickle-Charger/A_110354/article.html (http://autospeed.com/cms/title_Zero-Cost-Trickle-Charger/A_110354/article.html)
-
From the specs that appears to be a Lead-Acid battery. Look up the proper charge method (hint: Panasonic has a good app note) then use the idaes in z.s.tars's link to manually charge the batteries. Hint2: The charge cycle should consist of three states: 1- constant current, 2- constant voltage, 3- float. Trickle charging should never be used if you wish the battery to have a long life.
Once you get tired of doing that design and build a charger.
-
Hi,
How would I go about 'trickle' charging this?
You wouldn't!
At least not if you want the batteries to live a healthy long life.
Trickle charging is for batteries on standby that has already been charged.
I know a little about electronics, but since I don't want to mess these bad boys up.. I was hoping you could dumb it down a bit for me :)
(Was also hoping to say modify a phone charger or similar transformer to charge it, instead of buying a charger for it.)
I posted an automatic SLA charger design some time ago, it could be modified slightly (current increased a wee bit), but you would need to be able to make the PCB and build it yourself - are you up to that?
-
are you up to that?
Hell's yea, if you provide all the schematics and parts list :P
I'm always down for a little tinkering.
Cheers mate!
-
Hi,
Hell's yea, if you provide all the schematics and parts list :P
I'm always down for a little tinkering.
OK, here (http://That.Homepage.dk/PDF/12V_12A_SLA_Charger.pdf) it is.
The BOM is here:
Partlist for 12V/12A SLA Charger
R1 1R8 (2W)
R2 1k2
R3 0R2 (5W)
R4 220R
R5 22k
R6 2k2
VR1 470R trimmer
C1 100n
D1, D2, D3, D4, D6 and D7 BY550
D5 1N4148
LED1 Red or green LED
Q1 BC557
Q2 BC547
IC1 LM338-TO3 (on heatsink)
RL1 Relay
PB1 Momentary action Push Button Mains Rated Switch
X1 4-way Screw Terminal Block
X2 2-way Screw Terminal Block
X3 2-way Screw Terminal Block
If you cannot find a relay that fits into the PCB, or if you have another 12V activated relay with mains rated contacts (SPST, SPDT or DPST would all work as well), tell me and I can change the pads into whatever measures you give me - I just found a random relay for the layout.
The PCB can be cut along the white line and mounted as a "sandwhich" C1A should be connected to C1B etc. and not with a too thin wire (mains wire would be fine), whether you cut it or not.
The BY550 diodes could be BY550-50, BY550-100 etc. and could be replaced with any other 5A diodes.
Any questions I haven't foreseen, just say so.