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Gear / Technical Help => Remote Power => Topic started by: Eight_Tit_Chicken on May 03, 2011, 11:09:23 PM
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Hi everyone,
I'm TaperBruce. I am NOT affiliated with any of these buisnesses. I am NOT knowledgeable about batteries. I am not responsible for any mayhem that may occur by using these products.
LiFePO4
I just got this delivered today: (http://i1082.photobucket.com/albums/j372/TaperBruce/LiFePO4.jpg)
http://www.batteryspace.com/customizelifepo4battery64v10ah64wh10aratewithpcb.aspx (http://www.batteryspace.com/customizelifepo4battery64v10ah64wh10aratewithpcb.aspx)
Batteryspace confirmed that this is the recommended charger:
http://www.batteryspace.com/smartfastcharger12aforany64v2cells76vcut-offlifepo4batterypack.aspx (http://www.batteryspace.com/smartfastcharger12aforany64v2cells76vcut-offlifepo4batterypack.aspx)
(http://i1082.photobucket.com/albums/j372/TaperBruce/CompTable.jpg)
Voltage: 6.4 V (working), Min voltage: 4.5V, Max voltage: 7.6V
Capacity 10 Ah ( 64Wh)
Dimensions (LxWxH) 88mm (3.5") x 46mm (1.81") x 129mm (5.0")
Weight 820g (1.8lb)
Prewired 6.0" 14 AWG with Standard Male Tamiya Connector:
http://www.batteryspace.com/prod-specs/tamiya.pdf (http://www.batteryspace.com/prod-specs/tamiya.pdf)
Cycle life > 2000 cycles (80% of initial capacity @ 0.2C rate, IEC Standard)
One 10A Printed Circuit Board installed with the battery pack, that protects the battery from:
◦Overcharge (> 7.6 V)
◦Over discharge (<4.5 V)
◦Over drain ( >10 Amp)
◦Short circuits
http://www.batteryspace.com/prod-specs/4870.pdf (http://www.batteryspace.com/prod-specs/4870.pdf)
The Grace V3's LOW BATT indicator flashes if the battery voltage drops below 5.75V (Red arrow in Discharge Curve below). Preamp Shut Off is @5V.
Shut Off @5V compliments LiFePO4 Min voltage @4.5V Run Time during LOW BATT flashing to be determined. Should be useable.
LifePO4 Discharge Curve (double V for two cells). Red arrow @2.87V (5.75 LOW BATT FLASH):
(http://i1082.photobucket.com/albums/j372/TaperBruce/LiFePO4DisCurve.jpg)
Cost is 147$ plus shipping, plus make you own cable to preamp.
Battery: 98$
Charger: 24$
Hazard Material special handling fee: 25$
http://www.batteryspace.com/hazardmaterialspecialhandlingfeeperpackagetoshipviaupsfedexground.aspx (http://www.batteryspace.com/hazardmaterialspecialhandlingfeeperpackagetoshipviaupsfedexground.aspx)
Always Google for coupon codes. I found a 5% discount code that helped offset shipping.
Check out the Wiki for LiFePO4:
http://en.wikipedia.org/wiki/Lithium_iron_phosphate_battery (http://en.wikipedia.org/wiki/Lithium_iron_phosphate_battery)
For me the main benefits are:
CLEAN DC to my preamp. Just like a SLA. No DC-DC voltage regulator.
High capacity 10Ah
Huge increase in lifetime with over 2000 cylces. This really offsets the cost alot. I'm looking forward to powering the Grace trouble free for 5~6 years ?
Four times lighter then SLA batts.
Some of the Cons are:
May not be allowed on planes ?
Heavier then other Li-ion formulations.
Sticker shock $
25$ additional hazard material handling cost for UPS.
Non selectable voltage ;)
No fuel gauge.
Shrink wrap construction.
Just "safer" http://www.youtube.com/watch?v=DrUYJCdW4yw (http://www.youtube.com/watch?v=DrUYJCdW4yw)
Educate yourself on the hazards of Li-ion batteries !
http://www.youtube.com/watch?v=8ypUVpwgcAA&feature=related (http://www.youtube.com/watch?v=8ypUVpwgcAA&feature=related)
Tamiya connector. Altering connector VOIDS warranty
The usual suspects can easily fab a V3 power cable w/Tamiya. I'm not interested thanks.
I may still buy a Tekkeon. This LiFePO4 is a nice dedicated alternative.
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Hi Bruce!
welcome long time no see!
not much advice from me here but the LiFePO4 are excellent light weight batteries and the next generation - where we likely will all go in the future!
hope to see you soon
--Ian
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Update: (edit- see my next reply. Non issue)
The charger is getting too hot ? I've just sent an email off to the company about the issue. I'll let everyone know what I turn up.
The battery itself is roughly the weight of two "Wally" batteries. [or two Tekkeons]
Ian- It'd be good to do some taping with you this summer !
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Charger Update:
So glad I contacted Batteryspace before I tried to "fix" it (I fully intended to hack the cable). What I thought was a poor splice heating up, turns out to be :
"The location shown from your picture is with a diode there, it step down the voltage for charging, it will get hot as the battery will take full rating from the charger."
Here's a new pic of what I'm talking about:
(http://i1082.photobucket.com/albums/j372/TaperBruce/ChargerTipnote.jpg)
The Alligator Clips are awkward to use on the battery. I'll probably get a Tamiya connector with "leads" for the clips to bite onto.
So far... happy ;D
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It sounds like they may be selling a cheap charger, and not a true smart charger. Maybe something like this would work better and be safer?
http://taperssection.com/index.php?topic=145002.msg1866903
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It sounds like they may be selling a cheap charger, and not a true smart charger. Maybe something like this would work better and be safer?
http://taperssection.com/index.php?topic=145002.msg1866903
That other charger does have a LiFe setting (crucial). It is designed to charge individual cells in a pack. I don't think it would work?
The battery pack in this thread is just two large cells in series (with circuit protection=PCB). It's not set up for individual cell monitoring.
Batteryspace was the only distributer of this particular cell I could find. I refer all charger compatability options to them. They've been very responsive to my questions. They carry similar higher end smart chargers that are for "Battery pack without PCB". http://www.batteryspace.com/smartchargerfor32v-96v1-3cellslifepo4batterypackscells.aspx (http://www.batteryspace.com/smartchargerfor32v-96v1-3cellslifepo4batterypackscells.aspx)
I'm currently satisfied with the charger I got. pun