Hi Folks,
I have just added a second 48v 16s LiFePO4 pack to be battery cabinet. (Originally purchased the first 16s last year). Both packs "Non EV grade" which may be the reason for the behavior I'm seeing. Both JK BMS but new pack is 200a the older is 150a.
I added the new pack and full charged the system however the new pack was still drawing around 800w when the tail current limit of solar system kicked in and switched to float. The old pack was 100% (0 amps going into old pack).
Now whenever I'm charging/discharging the packs there's a voltage difference of about 0.1 to 0.2v, with the newer pack being lower voltage in both a charge and discharge scenario (with less amps to correspond).
If it was the other way around I'd have said it was due to aging of older pack. Could it be that the new pack is of lesser quality/higher internal resistance. Or am I overthinking it and I just need to have a longer absorption phase to ensure both packs are at the same SoC. (in case it matters to folk I set absorption at 55.2, 3.45v per cell, conservative I know...)
(I know the obvious answer is just charge the pack fully with the tail current disabled and find out but I'm having a very wet summer so it's been a few days and I was unsure if there was a quick way to confirm/deny my guesses).
I've done the basics of checking for any dodgy connections but all seems to be solid/no obvious hot spots. The new pack doesn't seem to tank to ridiculously low voltage when discharging/charging just 0.1 to 0.2v behind the old pack, which gave me hope that it wasn't just a dodgy pack.
Either way I'm stuck with the pack so worse case scenario the old pack will just be degraded faster if the new pack is worse.
I have just added a second 48v 16s LiFePO4 pack to be battery cabinet. (Originally purchased the first 16s last year). Both packs "Non EV grade" which may be the reason for the behavior I'm seeing. Both JK BMS but new pack is 200a the older is 150a.
I added the new pack and full charged the system however the new pack was still drawing around 800w when the tail current limit of solar system kicked in and switched to float. The old pack was 100% (0 amps going into old pack).
Now whenever I'm charging/discharging the packs there's a voltage difference of about 0.1 to 0.2v, with the newer pack being lower voltage in both a charge and discharge scenario (with less amps to correspond).
If it was the other way around I'd have said it was due to aging of older pack. Could it be that the new pack is of lesser quality/higher internal resistance. Or am I overthinking it and I just need to have a longer absorption phase to ensure both packs are at the same SoC. (in case it matters to folk I set absorption at 55.2, 3.45v per cell, conservative I know...)
(I know the obvious answer is just charge the pack fully with the tail current disabled and find out but I'm having a very wet summer so it's been a few days and I was unsure if there was a quick way to confirm/deny my guesses).
I've done the basics of checking for any dodgy connections but all seems to be solid/no obvious hot spots. The new pack doesn't seem to tank to ridiculously low voltage when discharging/charging just 0.1 to 0.2v behind the old pack, which gave me hope that it wasn't just a dodgy pack.
Either way I'm stuck with the pack so worse case scenario the old pack will just be degraded faster if the new pack is worse.