BEST - Battery SOC estimator
The LYNX firmware includes the BEST module to estimate the battery SOC (State Of Charge). LYNX uses the 4-point OCV variant — the cell OCV curve is entered as four voltages (U100, U85, U10, U0) plus the nominal cell resistance (Rc).
The BEST parameters are located in the /best folder.
Parameters
S
Number of cells in series.
P
Number of cells in parallel. Set to 0 to disable coulomb counting.
If the siliXcon controller is not the only power device connected to the battery, coulomb counting should be disabled since the controller cannot measure the total battery current.
soc_gain
How fast the SOC follows the measured cell voltage during run. Higher values re-align the SOC with the voltage faster, lower values give a steadier SOC. Set to 0 to disable voltage correction during run (voltage correction will still work during BEST reset).
reset_time [ms]
How long the SOC re-sync phase at device startup lasts. Negative value for manual-only reset via the breset command. Set to 0 to disable the reset feature.
reset_gain
How fast the SOC re-syncs to the cell voltage during the reset phase (reset_time after startup or breset).
Rs [Ohm]
Pack wiring resistance.
Cc [mAh]
Cell nominal capacity.
Rc [Ohm]
Cell nominal resistance.
OCV breakpoints [V]
The cell OCV (Open Circuit Voltage — the voltage on a single battery cell without load) is entered at 4 SOC points:
States
| State | Unit | Description |
|---|---|---|
SOC | 0-1 | Battery state of charge |
Permanents
Located at folder /permanents.
| Permanent | Unit | Description |
|---|---|---|
Cmax | mAh | Maximum battery capacity (at 100% charge) |
Cact | mAh | Actual battery capacity |
Shell commands
| Command | Description |
|---|---|
breset | Reset the whole BEST algorithm — SOC and SOH. During reset_time, SOC is corrected using reset_gain |