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All the voltage settings in the BMS, Loads and Chargers can be daunting to figure out. This paper attempts to explain the various settings, how they relate to each other and how to choose them.
Click on the orange 'download' button for the document
A big shout-out to @Dzl for helping develop this resource.
As with all of the resources I create, reviews, comments, suggestions and corrections are always welcome.
A nice related resource from @SteveS :
Note: This resource is a duplicate of the resource of the same name in the 'Beginners' resource Section. This resource is linked to the same download file.
4/9/22 Update: Added section discussing Accumulation Phase cut-off current and added appendix with a link to a good video from the Off Grid Garage channel.
All the voltage settings in the BMS, Loads and Chargers can be daunting to figure out. This paper attempts to explain the various settings, how they relate to each other and how to choose them.
Click on the orange 'download' button for the document
A big shout-out to @Dzl for helping develop this resource.
As with all of the resources I create, reviews, comments, suggestions and corrections are always welcome.
A nice related resource from @SteveS :
General LiFePO4 (LFP) Voltage to SOC charts/tables
Note: This resource is a duplicate of the resource of the same name in the 'Beginners' resource Section. This resource is linked to the same download file.
4/9/22 Update: Added section discussing Accumulation Phase cut-off current and added appendix with a link to a good video from the Off Grid Garage channel.
2.5V to 4.2V are the extreme limits of discharge and charge without immediate damage on LiFePo4. There is little reason to push the cells to these limits because they are well past the knees of the curve and the last .5V-.75v past each knee adds very little additional storage.
The bulk of the storage is obtained between 3.3V and 3.6V and most people will set their system up to be within that range. The most aggressive use will operate pretty close to these values, but a lot of people like to set things significantly less aggressive than this in order to prolong the life of the batteries. The key is to set the chargers and load to typically operate in your preferred range and set the BMS (2nd line of defense) at values that are outside the range of the Chargers and Loads but still within the 2.5V - 4.2V range. (if the system is working properly, it will never hit the BMS values). The trick is to set the BMS range as conservative as possible, but far enough outside the Charger/Load range to avoid unnecessary trips of the BMS.