RCinFLA
Solar Wizard
- Joined
- Jun 21, 2020
- Messages
- 3,559
Float only means no net charging current goes into battery.
Full charging depends on fully completing transfer of lithium ions into graphite. If you are at or above 3.43v and charging current has dropped to near zero it is fully charged. Some chargers exit absorb stage based on charge current taper down. Some chargers just hold absorb for a set amount of time.
Just going to 3.5v to 3.65v and immediately dropping to float voltage when it hits absorb voltage does not necessarily mean battery is fully charged. Overpotential voltage bump up in cell open circuit no load terminal voltage required to drive the migration of lithium ions depends on charge current amount. The greater the charge current, the longer the absorb period for charge current to taper down to achieve full charging. If you apply a low charge rate, battery will be fully charged when it reaches 3.45v per cell.
Full charging depends on fully completing transfer of lithium ions into graphite. If you are at or above 3.43v and charging current has dropped to near zero it is fully charged. Some chargers exit absorb stage based on charge current taper down. Some chargers just hold absorb for a set amount of time.
Just going to 3.5v to 3.65v and immediately dropping to float voltage when it hits absorb voltage does not necessarily mean battery is fully charged. Overpotential voltage bump up in cell open circuit no load terminal voltage required to drive the migration of lithium ions depends on charge current amount. The greater the charge current, the longer the absorb period for charge current to taper down to achieve full charging. If you apply a low charge rate, battery will be fully charged when it reaches 3.45v per cell.
