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.
LiFePO4I just got this delivered today:
http://www.batteryspace.com/customizelifepo4battery64v10ah64wh10aratewithpcb.aspxBatteryspace confirmed that this is the recommended charger:
http://www.batteryspace.com/smartfastcharger12aforany64v2cells76vcut-offlifepo4batterypack.aspxVoltage:
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.pdfCycle 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.pdfThe 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 LiFePO
4 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):
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.aspxAlways Google for coupon codes. I found a 5% discount code that helped offset shipping.
Check out the Wiki for LiFePO
4:
http://en.wikipedia.org/wiki/Lithium_iron_phosphate_batteryFor
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 Educate yourself on the hazards of Li-ion batteries !
http://www.youtube.com/watch?v=8ypUVpwgcAA&feature=relatedTamiya 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 LiFePO
4 is a nice dedicated alternative.