SLUUCH2 March 2021 BQ40Z50-R2
The following is the charging current degradation process (using Cycle Count as an example, although it would be the same for SOH).
In NORMAL mode (no ChargingCurrent() adjustment), ChargingCurrent() is reduced by CC Degradation Mode 1 (assuming the Cycle Count 1 entry conditions are met), then moving to Cycle Count Mode 2, ChargingCurrent() is further reduced by CC Degradation Mode 2 (assuming Cycle Count 2 entry conditions are met). This is similar for Cycle Count Mode 3.
The charging current mode transition is a one-way transition. The gauge only goes from Normal → Lvl1 → Lvl2 → Lvl3. The three degradation points each occur one time when that level is reached, with the amount of voltage degradation based on the related register.
This charging current degradation scheme (if enabled) must work in conjunction with any other existing degradation/increments (such as charge loss compensation).
The following table shows how charging voltage and charging current are degraded at different points:
| Cycle Count (in counts)/SOH (in %) (One or the other must be enabled.(1)) | Charging Voltage (CV) (CV degradation is available by default.) | Charging Current (CC) (CC degradation is available if enabled [Degrade_CC].(2)) |
|---|---|---|
| Normal | No CV Degradation | No CC Degradation |
| Mode 1 | CV Degradation (default 10 mV / cell) | CC Degradation (default 10%) |
| Mode 2 | CV Degradation (default 40 mV / cell) | CC Degradation (default 20%) |
| Mode 3 | CV Degradation (default 70 mV / cell) | CC Degradation (default 40%) |