Weekly full charge¶
Charges batteries to 100% once a week so the pack reaches the LFP top-balancing window and the integration can measure cell imbalance under repeatable conditions.
Charge profiles¶
| Profile | Description | Switch | Default |
|---|---|---|---|
| 100% charge voltage taper | Slows charging near top voltage window to allow some minor cell balancing | full_charge_voltage_taper |
On |
| Active cell balancing | Full cell balancing - repeated slow charge/discharge near top voltage window until cell_delta_V drops below 0.03 V or switched off |
active_balance_mode |
Off |
The 100% charge voltage taper uses the same voltage profile as a normal battery configured with max_soc = 100. The weekly feature only raises the target to 100%; it does not use a separate balancing algorithm.
Active cell balancing repeatedly cycles slow charge or discharge near the top voltage window until the measured top-voltage delta is at or below 0.03 V, or until the user turns the switch off.
Cell balancing
Active cell balancing is very slow. Reducing the top-of-charge cell delta by roughly 5 mV typically takes around 24 hours of cumulative time at the top of the balance window.
See Cell balancing for full details.
Drifted SOC
During the weekly charge the 3.58 V pause is not applied — charging keeps going at the tapered 95 W until the BMS itself cuts off. If the BMS coulomb counter has drifted (cells genuinely full but reported SOC below 100%), completion is still detected: the BMS-cutoff signature (charge ≤10 W with the inverter in Standby for 5 consecutive cycles) is recognised whenever the pack is in the top taper zone (≥ 3.48 V), regardless of the reported SOC. This lets the weekly cycle finish even when the pack never reads 100%, and best-effort attempts to recalibrate the SOC — depending on BMS firmware. See SOC recalibration on a stuck top voltage.
When the cycle completes¶
The weekly charge is marked Complete only when every battery is genuinely full — not merely when a cell touches the 3.58 V top voltage. A battery counts as full when either:
- its reported SOC reaches 100%, or
- a BMS cutoff is confirmed: charge collapses to ≤10 W with the inverter in Standby for 5 consecutive cycles (~10 s). During the weekly charge this is recognised whenever the pack is in the top taper zone (≥ 3.48 V), so a pack with a drifted SOC still completes.
The 60-second cell-delta measurement still runs as a diagnostic, but it no longer gates completion. On completion the configured max SOC (and the hardware cutoff register on v2) is restored, and charge hysteresis is re-enabled.
The Weekly Full Charge sensor exposes per-battery diagnostics under its batteries attribute: live SOC and BMS-cutoff cycle count while charging, and a completion snapshot (soc_at_completion, max_cell_voltage_at_completion, completion_reason, bms_cutoff_cycles).
Cell balance monitor¶
The cell balance monitor is only active when checked in the Weekly Full Charge Configuration. It records the voltage spread between the highest and lowest cell after each top-voltage measurement and keeps the sensor history, trend and alerts updated.
See Advanced options for full details.
Interaction with solar charge delay¶
If solar charge delay is active, the weekly charge can be postponed while the forecast solar production is sufficient to reach 100%.
When the weekly full charge is active, the integration bypasses the delay by default so the battery reaches the top-voltage measurement point and the balance reading is not skipped.
The Delay weekly full charge switch (weekly_full_charge_delay, on the Weekly full charge card) reverses this: turn it on to let the weekly charge wait for the solar charge delay to unlock, charging from solar instead of starting immediately on the target day. It only appears when both weekly full charge and the charge delay are configured.
Modbus register involved¶
This feature manipulates register 44000 (charging cutoff) to temporarily raise the limit.
Info
This feature is available for all supported battery versions (v2, v3, vA, vD).
