valence-u27-12xp-lifepo4
capacity testing with a charge-discharge-charge cycle.
its time to test ID-4 battery for fully capacity .
well start by hooking up a BM2 meter,
and a fully charge with the Victron 12/30/1
its already 98% charged so shouldn't take long . .
it starts pulling 19.6A from the 30A availible. . .
the tartget charged voltage will be 14.2v which is the Victron default for Lifpo4 . . .
as the voltage rises above 14.0v the internal cell balance kicks in . . .
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The battery is classed as fully charged when the current drops below 1amp and the voltage is above 14.2v (and the internal cell balance settles down)
Edit: next stage will be shown here . . . . . . . . . .
100% 14.22v 0.4A im happy with that . . . .
130ah / 138ah * 100 = 95.2% rated capacity
..
Discharge test next.
setup.
800va inveter, dehumidifier and heat gun drawing 40/45A
Ah meter zeroed . .
40A load verified with a second meter . .
..
inverter shut off set to 11v
ill run at 40/45A untill we get near the end . . . . then ill drop to 20A so that any voltage sag over the cables doesnt effect the final result . . .
TBC . . . . . .
here is the thermals . .
.
3hours later (drawing 45A, then 20A , . . . .
we fall of the cliff.....
we get a low battery warning , . . .
.
as the voltage drops / . . . .
.
discharge result . . . . . 130ah 1664wh 3:18hrs !!!!
.
next up is the recharge test to get back to 100% ...
The valence software shows the SOC wrong . . ., but it does show 30A input charge current . . . . . so lets see what the Victron 12/30/1 can put back in . .
charging at 30A things start to get a bit warm . . . .
you can see the 50A Anderson connectors getting hot at 30A continuous . .
edit: the heat was coming from the power meter and travelling along the short cables to the Anderson plugs , when the power meter was removed the Anderson were cool to the touch @ 30A / 14v
.
tbc . . .
Run out of pics (limit)
final recharge results:
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