The testing and BMS monitor is done, the battery looks like a good one.
here is the battery as delivered. . . . it shows 12.8V, but it actually almost flat. (cell @ 3.2v)
View attachment 51195
this is the battery BMS diagnostic lead i made up . . . . .
View attachment 51196
and this is the 150A inline power meter monitoring whats going on . . .
View attachment 51197
i used a Victron 12/15A charger on lithium mode to start charging . . . .
it maxed out the charger @ 15A until it got too hot and shut down to trickle charge . . . . !
so i added a second 15A NoCo G15000 charger, again same thing - maxed out @ 15A
i had the power monitor and the BMS was reporting a full 30A charge current going in . . . . thats all i had to hand.
The Valence U27-12XP will take a charge upto 70A !!! the these Lithium battery's are almost like a dead short on the chargers and will suck in all they can get.
the plan is to fit a Redarc BCDC1250D from
@travelvolts when they arrive, which has a 50A charge capacity. (runing on the OEM 80/100A original SCR cables)
This is what we had after a few charging sessions.
View attachment 51198
all green with no faults showing.
SOC is reported @ 100% and didnt drop over night.
I've kept the charger connected and above 98% the charge current starts to reduce . . .15/12/10/8/6/5/4/2/1A . . all the way down to 0.1A
It looks like the internal BMS is now trying to "top balance" the cells around 3.4v-3.6v
one thing to note is that the battery spec calls for 14.6v for the top charge . . . .
but both chargers have 14.2v as there set Lithium program? (the Redarc shows 14.5v)
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valence xp U27-12xp
battery specs.
Bulk 14.6v (3.65V PER CELL)
Absob 14.6v (3.65V PER CELL)
Float 13.8v (min 3.45v per cell)
C-rate. c/2 70A
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charger specs:
Victron charge:
Li-on mode
Bulk 14.2v/15A
Absorb 14.2v/15A
Float 13.5v
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Noco charge
Bulk 14.2v / 15A
Absorb 14.2v / 15A
float
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Redarc dc-dc charge. (bcdc1250d)
Bulk 14.5v / 50A
Absorb 14.5v / 50A
Float 13.6v
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heres some pics showing battery now full at 14.1 and the two chargers i used.
View attachment 51200 View attachment 51201 View attachment 51202
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any questions?
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