LiFePo Battery Difference

o1marc
o1marc Registered Users Posts: 1
I see these 4200 LiFePo batteries successfully used in pairs for starting a Mazda Miata. I found some 5000's and was wondering if that might not be better, but they have numbers that make me question it. With the stats below, would I better with 2-5000's or 2-4200's.

Capacity: 4200mAh
Voltage: 4S2P / 13.2v
Discharge: 30C Constant / 40C Burst
Max Charge Rate: 2C
Weight: 558g (including wire, plug & case)
Dimensions: 140mm x 45mm x 46mm
Balance Plug: JST-XH
Discharge Plug: 5.5mm Bullet-Connector


Capacity: 5000mAh
Voltage: 2S1P / 2 Cell / 7.4v
Discharge: 20C Constant / 40C Burst
Weight: 240g (including wire, plug & shrink wrap)
Dimensions: 144x49x18mm
Balance Plug: JST-XH
Discharge Plug: HXT 4MM

Comments

  • mvas
    mvas Registered Users Posts: 395 ✭✭✭
    edited March 2020 #2
    Are you going to use these batteries for Off-Grid Solar?
    Starting a car in second or two is very different vs running a DC-to-AC inverter for many hours.

    4200 mAh = 4 Amp-Hour
    5000 mAh = 5 Amp-Hour

    Do you have a URL link for each?
  • Raj174
    Raj174 Solar Expert Posts: 795 ✭✭✭✭
    Are you sure the 5000 is LiFePO4? The voltage is a little high, more like lithium polymer cell voltage of 3.7v. And at 2S1p, not the same voltage (7.4v) as the 4000 (13.2). So it doesn't sound like it would work in place of a 4000.
    4480W PV, MNE175DR-TR, MN Classic 150, Outback Radian GS4048A, Mate3, 51.2V 360AH nominal LiFePO4, Kohler Pro 5.2E genset.