My i4 terminate charge voltage, with a quick measure with Fluke 115, 4.18-4.20v depending on old or new cell, wheres the i2 I get 4.21v
I don’t think its overcharging as scaru pointed out 
I have 2 Fluke meters exactly alike, same model and they don’t read exactly the same. I wouldn’t worry about it and .2 is nothing to worry about in the first place.
Is this “DMMCheck”: http://shop.voltagestandard.com/product.sc;jsessionid=D054C40529675D03D2AA78DD5632D3E0.qscstrfrnt03?productId=3&categoryId=1 a good reference?
Or DMMCheck Plus is better?
Plus he has unbeliveably good customer service and will recalibrate the devices for about the cost of a cup of coffee.
The plus can calibrate more ranges and the resistors for ohm calibration is slightly better.
The PentaRef is also very useful for DMM voltage calibration, because you can order one with a 4.2 volt value (Then you now your DMM is correct for LiIon), or for more general purpose, select as needed from: 1.9 (2000 count DMM), 2.9 (3000 count DMM), 3.9 (4000 count DMM), 4.9 (5000 count DMM), 5.9 (6000 count DMM).
Checking my batteries after they are on the i4, I'm also usually seeing 4.21-4.22 not 4.2 exactly. I don't think it's really a big enough of an issue, since it does stop charging at that point.
mine stops at 4.217. my fluke is calibrated
What batteries are you guys using to get these results? If they are newer higher cap batteries it could (Accurately) detect that it could push more voltage into them and do such. I had my i4 give out at 4.17 on my older sanyo 2200’s batteries and about 4.19 on my newer 2600’s.
Then again my meter is junk, but it still is reasonably consistent. I still trust my accucel 6 more than the i4, which on the same cells and meter stops at 4.15v and 4.17v respectively.
I used 4 trustfire lightning from fasttech
they are pretty new, three charging cycles or so.
Calibrated by who, what are their qualifications, and in what Amb conditions and can the calibration be traced back to national physics lab?
Can you tell I like an audit.
No. The differences in termination voltage are either
A) Random variation. The Analog Voltage measurement circuitry has precision error from one cycle to another, especially if the room temperature changes.
or
B) Caused by the time between actual charge termination and your measurement. Once the charge terminates, there will be a little fall-back in voltage. If you wait longer after termination, the fall back will be more.
or
C) Your meter has precision error from one measurement to another
or
D) The Charger follow correct CC/CV Charging protocol, and every battery will take current a little differently once near the end of the CV portion of the charge
or
E) a combination of the above.
They are not, however, due to the charger “Sensing” the higher voltage tolerance of the cell and charging it higher.
PPtk
edit: To add Option D - Brain malfunction and I forgot to type that one out…
my nitecore i2 charges the sanyo 2800 up tu 4,24v when measured right after charging and it drops to 4,23v an hour after…
the panasonic 2900 are terminated at 4,22v…
Despite of your suspicion, it is calibrated monthly every second month by a laboratory only dedicated to do such things. I can’t tell you the name,I don’t know it because the fluke is not exactly mine, it’s part of the tool set my company provides me to do my job. But I borrow it when I need to measure some important thing like this
Cat tell you much about the calibration process, but trust me, in my company they are really obsessed with precision-calibrations-torque settings-deviations, so I think the fluke is properly calibrated.
Edit: for future reference, all my other tools like caliper, feeling gauges or torque wrenches are also calibrated. The lab has ISO certification, is all I know
According to my craftsman DMM, my i4 charges my 3400mah protected Keeppowers in the the 4.22 - 4.23V range.
Both (i4 & i2) definitely slightly overcharge (4.22-23V)
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I posted over in gords i4 "poof" thread, but thought it more appropriate here since we're talking about the i4's termination voltage.
Charged up my two protected KeepPower 18650 3100's (charged in separate channels for the 750mA rate). Fresh off the charger I'm measuring 4.27v and 4.28v! I let them sit 20 minutes and still saw 4.27v & 4.28v. Here it is 4 hours and 25 minutes later and I'm still seeing 4.27v & 4.27v. I'm using the same meter I always use and no other charger I have charges this high. My i4 has a molded serial# which matches the box's label. This is my first use of this charger.
So how high is too high? And at what voltage should the over-charge protection kick in?
-Garry
Try replacing the battery in your meter.
I don't think it's the meter's battery. I just tried measuring with a cheap junky Harbor Freight DMM known to be measure a few hundredths of a volt lower compared to my good meter (at least by experience measuring the same li-ion cells after charging) and it measured 4.23v on each one. I then pulled a brand new Duracell alkaline from a pack and measured it with both meters: good meter - 1.624v, cheap HF - 1.616v. I don't have another good meter to try and can't pull the battery out of the good meter now (I'm at work).
-Garry
Wow, that’s too much IMHO 
Overcharge circuit kicks in before 4.32/33V ± 0.03/05V (i.e. ± 1%) if I remember well.
I would contact who ever you got it from Garrybunk and let them know what its doing once you verify your meters reading.
That could be dangerous with a older cell with high internal resistance.
The higher terminated voltage is also shortening the life of your cells permanently . It would be better if it terminated early.