I think about using the XIAO ESP32C3 for a measurement sensor and would like to attach a LiFePO4 battery to it ( https://asset.conrad.com/media10/add/160267/c1/-/en/000250796DS01/datenblatt-250796-emmerich-ult-18650-fp-ulf-spezial-akku-18650-u-loetfahne-lifepo-4-33-v-1250-mah.pdf ).
Can the integrated battery management system handle LiFePO4 batteries as well, or is it meant to be used with LiPo batteries only?
Do I need to keep something in mind if I attach a LiFePO4 battery?
If everything works with the LiFePO4 battery, then I should be able to use the USB-C connector for charging, right?
Thank you for your time and ansers.
Does someone have any idea what kind of battery management system is used? I looked at the FCC images and could not figure it out and the ESP32C3 datasheet shows no integrated BMS, so I assume it must be a separate controller?
If I knew that, I could look up the charging voltage.
XIAO_ESP32C3 uses a charge controller that I believe is MCP73831. Please check the datasheet. Also, the following link may be helpful.
XIAO_nRF52840 and XIAO_ESP32C3 have a built-in charging function, but since the circuit diagram was not disclosed, I assumed that they have the same circuit. I was curious and measured the charging characteristics. They are completely different, XIAO_nRF52840’s charging current can be set to 50mA or 100mA by firmware, but XIAO_ESP32C3’s is fixed and very large at 370mA, so I need to be very careful when using small capacity batteries.
Thank you for your reply, that was very helpful!
I looked the MCP73831 up and found this document
https://cn.element14.com/wcsstore/ExtendedSitesCatalogAssetStore/cms/asset/pdf/apac/common/storefronts/microchip/BatteryPowerApplicationsDesignGuide.pdf which describes the different BMS on page 6 and lists the MCP73123 as specifically designed for LiFePO4 unlike the MCP73831.
This document (
https://ww1.microchip.com/downloads/aemDocuments/documents/OTH/ProductDocuments/DataSheets/22191E.pdf ) shows that the charging voltage for the MCP73123 is 3.6V, so I assume the 4.2V in the XIAO ESP32C3 would be too much.