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6 hours ago, WI_Hedgehog said:

How can this be? Well, as the battery terminal voltage approaches the charge cutoff voltage (such as 4.20V for a 1S battery) the charge slows down. If the charge voltage was 4.20V, the battery would form a surface charge of 4.2V and stop charging. As the surface charge dissipated the true battery voltage would be 4.18V (or something similar). Therefore, the charge voltage for 4.2V is something higher, say 4.4V and the current cutoff is set at some percentage of the charge current, related to the charge voltage.

This effect can also be seen nicely in the "(almost) standard charge graph" of the ncr18650ga (cells used for veteran?) from https://lygte-info.dk/review/batteries2012/Sanyo NCR18650GA 3500mAh (Red) UK.html Sanyo%20NCR18650GA%203500mAh%20(Red)-Cha

Charging is performed with 1A ~0.3C and stopped at ~0.1C. Cell voltage settles within some half hour/hour to a bit below 4.2V.

If the chargery charger really has some smart fast charging mode, that uses higher charge voltage than 4.2V per cell this would be an explanation for premature charge input cut off - as each EUC BMS cuts of once any cell reaches 4.2XV!

So such a mode should will not work with any EUC, not only Veteran!

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I'm wrong, the Chargery reportedly uses 4.20V as do other EUC chargers. Simple, cheap, light, and fairly safe. Fast--no, but "faster."

From the information I've seen I would guess the Veteran BMS does seem to stop the charge cycle to check the battery state and if the battery test comes back "sane" the BMS continues charging the battery, which works fine with a standard power supply that doesn't care about the lack of current draw and continues supplying power as needed. 

The Chargery, from the manufacturer's site, seems to be a smart charger in the respect that when the charger detects output current has fallen below a certain setting it stops the charge to prevent trickle charging the battery, so a "sanity check" by the BMS is causing the Chargery to stop charging.

I have to thank @Chriull, @mrelwood, and @RagingGrandpafor continuing to help me understand how EUC chargers & BMS units work vs. what I'm used to. It's a constant "you've got to be kidding me" situation. I'm happy to lean though, and they've been great.

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