Other Parts Discussed in Thread: BQSTUDIO, EV2400
Hi,
I am using the BQ35100 gauge sensor to monitor the condition of battery in my project. The cell I'm using is of Lithium Thionyl Chloride chemistry (33600 SAFT).
For calibration purposes, I'm using EV2400 and BqStudio. I need to find out the State of Health (SOH) value of the battery I am connecting. However, I'm facing an issue where the SOH is not decreasing even after connecting the load.
Here are the steps I have performed:
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Made the GE pin high.
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Switched to End of Service (EOS) mode by setting GMSEL1:0 in Operation Config A to 10.
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Connected a load (18 ohm resistor) across BAT+ and PACK-.
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Sent the GAUGE_START command.
I am setting an SOH value initially. Is this always necessary? What happens if the battery I'm connecting has an unknown SOH initially?
The calculations I've done is as follows:
The total lifetime of the battery is: Time (in hours) = 17 Ah / (200 mA) = 85 hours
So, for a 1% discharge to happen, time = 51 minutes.
Even though I've connected the load for 1 hour, there is no decrement showing in the SOH in BqStudio. However, when I toggle the GA bit, there is a 1% decrease (State of Health Max Delta) in SOH.
Kindly reply if there are any changes to be made in the steps I'm following. Are there any other configurations or changes I need to make?
These are the values I've set in Gas_gauging->design.
Thank you in advance,
Arun Babu
