[Vincent Rapide]

As I've posted before, when using one of those digital cigar-lighter-plug voltreaders you get an immediate reading of the 12v lead-acid battery voltage, say 12.2v, then followed closely by the 14.5v reading as the dcdc charger turns itself ON. But sometimes the reader is not pushed all the way into the cigar socket, or twisted into full contact, etc. So if it doesn't work on first try, turn OFF the key and wait 15 seconds for the car to turn itself OFF, and then try again. Usually it works ok and you get the momentary 12.2v reading which gives you a sense of just how pathetic a condition your lead-acid powerhouse is in as you skirt the edge of EV-insanity.
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[Vincent Rapide]

Wow, Vincent! Very insightful! That’s a great observation!!

. . . faint praise indeed . . . 8^)

 

[Vincent Rapide]

I usually get readings in the 12.2 > 12.4vdc range when the ED3 or the Chevy SparkEV has been idle for a few days. Go figure. Maybe there are other instantaneous current draws happening just before the dcdc kicks in. The Sparks originally came with genuine AGM batteries so maybe that is an inherent characteristic of AGMs. Certainly you don't want to see a batt dip below 12.2v - then it would need immediate recharging.

My 2016 ED3 built 5/2015 still has an OEM batt so I assume it is the actual factory installed battery. Yes, I'm tempting fate, but I'm using the car every few days and when I leave here the batt gets disconnected and put on a float charger (see separate thread on this).
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[Vincent Rapide]

> I get over 14V on the display right away ... [Marginal]

Then I would ask what year is your ED3. My 2016 may have a slight delay in the DCDC turning on, which proves useful. If it had no delay I would go to the small trouble of hooking up an external voltmeter wired directly to the 12v battery. The idea is to read the 12v voltage accurately just before you turn the key ON.
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