Suggestion for additional SOC calibration and battery cell balancing functions.
During intensive use of charging stations, two potential issues need to be addressed manually: calibrating the station’s battery charge readings and balancing the battery cells. Failure to do so is guaranteed to cause problems.
You yourself regularly recommend manual procedures that address these two issues.
Why doesn’t Bluetti refine and implement these functions as additional service features in the station software and app?
Of course, the following description of additional calibration and balancing procedures doesn’t fully describe them; it merely provides a direction for further study and development, as I don’t have a complete understanding of how the software is organized or whether existing charging stations have all the necessary parameters. However, this could at least be taken into account and implemented in new charging stations.
- SOC calibration – a separate setting that initiates the calibration procedure.
The system warns that it needs to be connected to an external power outlet, connect a load of a certain power (minimum), and warns about the approximate runtime. During the procedure, the power cable must be connected to an external power source, and the station must remain under load until fully discharged, and will remain unloaded until fully charged. The user again agrees and confirms.
The station then disconnects the external power source, discharges the battery from the external load to zero, charges it to 100%, and then indicates that the procedure is complete.
The calibration function can also be configured differently: the user enables the CALIBRATION option in the app, which means that upon the next discharge to zero, the station will turn on charging, will not connect the load until the battery is fully charged to 100%, and only then will it turn on the external ports.
- Cell Balancing.
Since passive balancing is used, this can be an option – a one-time, a fixed number of times (2-5), or continuous.
The idea is that when the user enables the balancing procedure in the settings menu, the station automatically reduces the charging power the next time it charges above 90% (the level is determined by the cell and balancer properties), and charges the battery with a specified minimum current (e.g., 0.2C, also determined by the cell properties). Accordingly, a one-time charge is defined as a single charge from the moment of activation, fixed charges are defined as a set number of 2-5 subsequent charges, and continuous charging is defined as a continuous balancing procedure. This procedure can be controlled with or without connected loads.
You can also analyze the amount of station usage without calibration and balancing, display it in the app, and even provide reminders to perform the procedures. Reminders can also be disabled, but they should be enabled by default. Disabling reminders should also include a warning, ensuring the user knows what they’re doing.
These two features will significantly simplify station operation and reduce customer complaints about battery issues.