Hey guys I am working on SparkFun LiPo Fuel Gauge with esp32 using arduino to monitor battery state of charge for 5 lithium ion cells in parallel (4.2V 10Ah). I am not getting accurate results for voltage and SOC. For voltage, I am getting 0.1 difference with multimeter and fuel gauge which can be accepted. But for SOC, I am getting unreasonable differences.
May be I am doing something wrong, But I need to confirm few things, i.e. I can work with lithium ion cells or lipo cells as the chemistry is the same. The other is that it mentions it is for single cells (mentioning voltage), So I can use it with 5P for coulomb counting(SOC). Right?
Can you take a few photos of the circuit you have the Fuel Gauge in or, if possible, a schematic/drawing of the circuit as well? If I were to guess based on the information you’ve given here, I would assume the SoC reading is being affected by the batteries in parallel or something in your code is off. If you connect a single LiPo to the Fuel Gauge and adjust your code accordingly, do you get better results for SOC or the same?
According to the [datasheet, the MAX17043 does not use traditional coulomb counting for SOC and instead uses an algorithm called “ModelGauge” so you just need to call the SOC register. We do not have an official SparkFun library for this board but there a rudimentary library that might work with the ESP32 [here if you want to give that a try (assuming you are not already attempting to use that). Otherwise, can you please include your code in your reply so we can try and replicate the issue here? We cannot help debug custom code but it might help us identify why you are getting bad data for the state of charge with this breakout.](Additional-files/TOL-10617 at master · SparkfunTechSupport/Additional-files · GitHub)](https://cdn.sparkfun.com/datasheets/Prototyping/MAX17043-MAX17044.pdf)