Does the MAX17043 already internally compensate for temperature in any way?

Components & Accessories Power
1

Hello everyone,

I’m working with the MAX17043 on a JN5168 to measure the state of charge (SOC) of a Li-Ion battery. I know that the CONFIG (0x0C) register contains the RCOMP field, which adjusts the ModelGauge™ algorithm’s compensation, but the datasheet doesn’t provide clear details on how to modify it for temperature compensation.

Since the MAX17043 does not have an internal temperature sensor, I am exploring ways to adjust the SOC estimation for temperature without using an external sensor. Here are some ideas, but I would love to hear from anyone with experience or suggestions:

  1. Using a fixed RCOMP value based on expected ambient temperature (e.g., 0xA5 for cold, 0x97 for normal, 0x85 for hot conditions).

  2. Estimating temperature based on battery voltage:

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    If the voltage decreases slowly, it might be due to higher temperatures.
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    If the battery is fully charged (4.2V) but the SOC drops quickly, it could indicate a low temperature.

Any other recommended strategies?

2

That sounds viable. Pg 4 does show a Volt vs. Temp graph that is only estimating ~14mV error @ -40c for 4.2v battery (so, worst-case scenario), and almost no error for 85c

You might not need to adjust much…