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Hi Jon,
I'm comparing with the AGM sealed lead acid
batteries that I've bought. These are a bit more expensive than lead
acid.
Looking at this site wich sells only AGM
sealed lead acid & lifepo4.
4 of the 40 ah lifepo4 3.2v comes
to $240- & 1 of the AGM 44ah is $135-,
however the lifepo4 are rated for 2000
cycles whereas the AGM are 400 cycles.
The Lifepo4 batteries are typically 65% of the volume of lead acid
batteries & 1/3 the weight
There is also the depth of discharge issue where if you go beyond 50% with
AGM batteries you dramatically reduce there
life. However the Lifepo4 can be discharged to 80%
Below is a comparrison chart for batteries used for a solar power system.
Note that the lead acid is 92 AH & the Lifepo4
is 40 AH. I think the factor of depth of discharge with the Lifepo4
makes them even more advantagous to our use, in that for less
space you can have twice the power available.
I've just started looking into this so am no expert, but the figures are
looking good.
Regards Alan
*Lead Acid
Volts: 12 AH @ Standard C: 92 Cost: $200.00 Lbs: 63 Operating Temp: -40ºC to 60ºC Standard C Rate: 0.05 Cycles @ Standard C: 3100 Power Density: 55.2 DoD: 30% Usable Whr: 331.2 $ / Whr: $0.60 Lbs / Whr: 0.190217391 *LiFePO4 Volts: 12.8 AH @ Standard C: 40 Cost: $232.00 Lbs: 13.2 Operating Temp: -45ºC to 85ºC Standard C Rate: 3 Cycles @ Standard C: 3000 Power Density: 1536 DoD: 80% Usable Whr: 409.6 $ / Whr: $0.57 Lbs / Whr: 0.032226563 ----- Original Message -----
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