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urbanr avatar image
urbanr asked

BM-712 shows 100% instead of real value 92%

img-7255.pngimg-7265.pngimg-7254.pngI have 2x 160Ah Sunlux Lithium batteries. My problem is that the BM-712 always shows 100% before it is fully charged compared to reality and the Sunlux app. What can be the problem? see my attached pictures.

BMV Battery Monitor
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img-7254.png (254.8 KiB)
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Alexandra avatar image Alexandra ♦ commented ·
@UrbanR

Your bmv is set up differently to the sunlux. The real question is the sunlus also accurate? Does it use a shunt to measure?

What i would suggest is that you set your charged voltage much higher, since it is a lithium battery. What is the bulk/absorption target for the battery? The charged voltage should be quite a bit above float level but not too close to the bulk voltage

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urbanr avatar image urbanr Alexandra ♦ commented ·
I hope they are correct. It is directly from the BMS.
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Alexandra avatar image Alexandra ♦ urbanr commented ·
What has happened is the 100% has been triggered too early there.


Reason

1. Charged voltage is low. Use @klim8skeptic suggestion there.

2. Charge rate is also low.

There is a total of about 3.4A there which is just around the 4% threshold of tail current and you above the charged voltage set on the bmv.


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1 Answer
klim8skeptic avatar image
klim8skeptic answered ·

@UrbanR you could adjust the BMV setting "Charged Voltage" to 0.2 volt below your chargers bulk / absorp voltage.

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urbanr avatar image urbanr commented ·
I have tried it now, the bulk voltage is 13,8 so I changed the setting to 13,6 will see if it helps.
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