Navy Sub days, if you went to zero, you could get reverse polarity and that whole cell would be effed (isolated, hauled out next dockyard visit). Can this happen with Fox batteries ?
Farfarer wrote: ↑Tue Aug 11, 2026 2:09 am
Navy Sub days, if you went to zero, you could get reverse polarity and that whole cell would be effed (isolated, hauled out next dockyard visit). Can this happen with Fox batteries ?
Ouch, that would take some heavy lifting to sort !, I used to have the similar problem with model boats (and NiCd batts) and changing them was a pain
Fortunately Lithium batteries won't go negative but when they fall below a specific voltage level they typically become un-recoverable.
Typically, all larger Lithium Ion (or Lithium Ion Phosphate 'LFP' as is the case with solar batteries) have a battery management system that avoids the possibility of the batteries dropping below a critical level, and they will disconnect the battery output to avoid any further discharge - in most cases the will signal an immediate charge. With Fox inverters the moment they drop to that level the inverter will provide cyclical 'top up' 5A maintenance charges to keep them at the minimum level.
That said LFP batteries do have an internal resistance and will discharge very slowly whether connected or not, if left powered off they will gradually lose charge and if left long enough will eventually drop below a recoverable level - not a good place for them to be, and at that point they may, or may not be recoverable (i've seen both) but they can only be recovered with a direct charger often connected straight onto the internal battery terminals to bypass the BMS etc..
