High Voltage Battery Heating - NOT Possible cause of 12v battery drain

[GPSMan]

@Automate I believe this is what you are looking for.

This was a picture I took at startup yesterday in 46* degree ambient temps. I have waited to post this, but this differential is what I am seeing regularly at cold start.

Thank you

You and me both see +/- a 20 degree differential.

I'm seeing this consistently.

It's likely the scangauge conversion is off. The raw data is hexadecimal code that has to be converted to degrees F. You can have degrees C or degrees K or degrees actual times 47 minus 13.8 if that suits your fancy.

Look at it and mentally subtract 20 from battery coolant the next few days and I'll bet things make sense. It does for me. Again today, after being parked all night and everything should be in equilibrium, a 20 degree offset.

58 outside air = 78 battery coolant.

66 outside air = 86 battery coolant.

Afternoons

79 outside air = 99 battery coolant.

95 outside air = 115 battery coolant.

115°F battery coolant did not make sense to me before. But now it can be explained if the actual value is 95 like ambient air and cooling was right on the cusp of kicking on at 96°F.

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[MakinDoForNow]

You and me both see +/- a 20 degree differential.

I'm seeing this consistently.

It's likely the scangauge conversion is off. The raw data is hexadecimal code that has to be converted to degrees F. You can have degrees C or degrees K or degrees actual times 47 minus 13.8 if that suits your fancy.

Look at it and mentally subtract 20 from battery coolant the next few days and I'll bet things make sense. It does for me. Again today, after being parked all night and everything should be in equilibrium, a 20 degree offset.

58 outside air = 78 battery coolant.

66 outside air = 86 battery coolant.

Afternoons

79 outside air = 99 battery coolant.

95 outside air = 115 battery coolant.

115°F battery coolant did not make sense to me before. But now it can be explained if the actual value is 95 like ambient air and cooling was right on the cusp of kicking on at 96°F.

Ok consider this thought. Internal resistance heater (common in 12v lithium batteries) in HVB powered by hvb bus with voltage switch to limit draw to (say 25-30%) soc along with cut off at some temp. Would be advantageous to be on until just before battery cooling would be required. Internal resistance would be most efficient method and HVB capacity above a 25% is there to use. No pumping or external heat wasted. From what I've read, studies have shown that lithium ion charge and discharge rate can be increased until the electrolyte starts to melt which results in thermal runaway. The thermal strips could be several to provide redundancy along with maybe different on/off points.

 

[MaveRichard]

You and me both see +/- a 20 degree differential.

I'm seeing this consistently.

It's likely the scangauge conversion is off. The raw data is hexadecimal code that has to be converted to degrees F. You can have degrees C or degrees K or degrees actual times 47 minus 13.8 if that suits your fancy.

Look at it and mentally subtract 20 from battery coolant the next few days and I'll bet things make sense. It does for me. Again today, after being parked all night and everything should be in equilibrium, a 20 degree offset.

58 outside air = 78 battery coolant.

66 outside air = 86 battery coolant.

Afternoons

79 outside air = 99 battery coolant.

95 outside air = 115 battery coolant.

115°F battery coolant did not make sense to me before. But now it can be explained if the actual value is 95 like ambient air and cooling was right on the cusp of kicking on at 96°F.

Did you hear back from Linear Logic about programming/offset/firmware?

 

[GPSMan]

Did you hear back from Linear Logic about programming/offset/firmware?

No. Let me ping them again.

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