Doing a 12V battery test

[camellia30]

I have logged with a current clamp, idraw was sub 20mA. I do not have passive entry.

The current clamp had an auto-off, so logs were only about 20 minutes. The clamp ir not exactly made for such low currents, but i'd "calibrated" it with an electronic load and am fairly confident with the result.

[Dala]

3 hours ago, Corollanutter said:

 

can you send this table with the temperature and voltage values?
it's the other two cards
for comparison
Thank you

[Corollanutter]

40 minutes ago, Dala said:

can you send this table with the temperature and voltage values?
it's the other two cards
for comparison
Thank you

Here you go. Also added the 1 day versions too to show more detail. 

[Corollanutter]

4 hours ago, Roy124 said:

Looks like I had done that, I tweaked the 100% SoC to 12.95v.  I have SoC 64 and 12.44v  Lower voltage, higher SoC but the displayed voltage is what is wrong.

I will check mine tomorrow against my multimeter and let you know if it correlates. 

[Dala]

I also have big voltage drops
these drops will slow down at 12.3V and below
large parasitic current consumption or a bad series of YUASA car batteries
This is how I've been since I bought the car

 

[Roy124]

Odd though the results are I am beginning to believe my multimeter may be wrong.  I used a second meter and it was just 0.1v higher than the BM6. 

On charge the BM6 showed 100% SoC, as you would expect, and a voltage about 14.55.  Switching off the charger the readings decayed slowly to 12.96 and SoC of 75%.  

As yesterday's trips were no more than 20 minutes each the BM6 SoC may indeed have been close enough.  

I will give it a bit more time and see what it shows after an hour or more off charge and then when I drive it.

[Roy124]

Just done another check, off charge at 1000, at 1015 87% and 12.77v.  It was steady until 1215 when it had dropped to 12.66v and 75%.  At 1300, 12,59v and 69%.

I suspect the readings are pretty close although rather surprising especially after have been at 100% at 1000.

[AisinW]

15 hours ago, Corollanutter said:

Here you go. Also added the 1 day versions too to show more detail. 

It is absolutely normal and in good condition. The charge state of the Battery after few hours no more surface charge is about 12.3-12.5V. Don't worry about it. You will read higher Voltage if you disconnect the - terminal and trully at open circuit voltage ~12.5V.   

The main important point is the stability under load. If it is always above 10V during high load, the car will still start.

[Roy124]

I have cracked it, or rather how the voltage relates to the SoC.  The BM6 gives the standard AGM comparator.  Alter the % and you alter the SoC setting.

Regular Lead Acid and AGM clearly give the standard figures and custom allows you to alter the SoC value presumably for temperature correction.

I see the Intelligent power algorithm calculates Battery power - SoC?

The other option is Voltage corresponding to power.  It says power will jump quickly.

Does the IPA smooth out the SoC change and the VCP give more rapid change?

[Roy124]

Next question.  CTEK, on their Comfort indicator say that the yellow light illuminates between 12.65v and 12.4v which says you should recharge the Battery. 

The BM6 displays a voltage of 12.45v 48 hours after I last drove and has been steady for the last 36 hours. 

What would be a typical SoC for the 12.65v and 12.4v?

[Dala]

great solution from KIA:

https://www.kiaevforums.com/threads/some-12v-battery-findings.6229/