arnis wrote:Therefore OBD is big NONO to keep plugged in.
Agreed. The LEAF with an ELM327 plugged in is MUCH worse on the battery than without it. I used to keep mine plugged in, but now I instead unplug it when I get out. That's harder on the OBDII connector, but better for the battery.
arnis wrote:Also I noticed 14,48V reading while L2 charging today. That must have continued for an hour at least. Went for a drive and voltage dropped to 13,06V few minutes after takeoff.
Yes, that's the 12V charging that I mentioned that occurs during Li-ion charging sometimes
. It seems to do this every time in very cold weather (below about 20F), but I have not found the pattern for other conditions (partly because I just don't look for it). FWIW, mine stopped charging the 12V battery after less than one minute today when I charged the car.
I think Nissan would do much better if they set a MINIMUM time to charge at 14.5V of 30 minutes or some such to handle the cases which they currently do not address properly.
arnis wrote:Was able to make a 20A load with head and taillights (incl fogs). I'll try to discharge 12V for half an hour at off state. And take a drive shortly after.
I won't be too surprised surprised if it restores the lost charge fairly well, since it can meter such high currents. The issue is that the measurement resolution in the LEAF is only 1A, so it cannot tell what goes on when the car is off and the current draw is very low, as TimLee has mentioned:
TimLee wrote:Where Nissan messed up was on standby power use for some people.
They do not appear to ever do what an inexpensive battery maintainer does.
Most of what they do is all based on current that has been measured coming out of the battery.
When LEAF is OFF they see nothing so they miss standby losses.
This is clearly seen in the plot I linked to previously
Note that following the charge by the external Battery Tender at midnight at the end of April 5, 2015, the resting voltage on the AGM is 13.25V. (Note that the charger was unplugged at about 4:00 AM, along with a door to the LEAF being opened. This resulted in an additional load on the battery until the LEAF went back to sleep, followed by a RISE in voltage back to above 13.2V.) Then when the LEAF is plugged in to charge on the morning of April 6, 2015, the LEAF briefly spikes up to 14.35V and then DISCHARGES the battery down to 13.10V. Then following that event, you can see that all of the activity of the LEAF does ABSOLUTELY NOTHING to increase the SOC on the battery. That is why the overall shape of the curve is simply an exponential decline (which is due to whatever standby load there is on the 12V from the LEAF). Simply put, the brief 14.5V spikes and the float voltage of 13.1V did not increase the SOC of the battery in the least. That algorithm WILL keep the battery charged to about 60% SOC (resting voltage of about 12.3V), which is the recipe for sulfation. Of course those who use the windshield wipers frequently will see better results.