The 8hr thing is myth and a spill over from old battery chemistry. Although many batts will not come fully charged, once placed in a charger and the light goes green, they are fully charged..
It is and it isn’t..
I agree the batteries do come charge and lithium ion batteries do not have a memory so giving them a full charge is not by the book..
BUT…
From time to time I get a customer who says their battery out of the box isn’t working. It lasts for 5 mins and starts flashing, so they charge it, takes maybe 5 mins light turns green on the charger, but same problem, it lasts 5 mins then it is dead.
How I solve that problem is I tell the customer to charge it for 8 hours uninterrupted. Ignore the green light on the charger. This seems the “reset” the battery. What happens if you have 8 hours to kill to watch it LOL is over that 8 hours it will cycle, slowly between green charged and red.
Yes I know, that’s not how lithium ion works, but I think it has something to do with the electronics of the PV itself. I think when shipped it discharges a bit too much and trips the voltage stop?? Who knows.. What I do know is about 1 out of 100 eGO batteries have this problem out of the box. Of those 95% can be corrected with this method.
I also recommend that as often as possible the user charges their eGO battery overnight. Again giving that good 8 hour charge. Reason for that is not based on the science of lithium ion but on the fact that the eGO batteries I use, the paint is starting to fall off them I’ve had them sooo long..
Theory.. Maybe the electronic in the PV there is double protection. One circuit measures absolute voltage, while another measures the change in voltage. While shipped the battery creeps down in voltage, throwing on the voltage difference protection circuit. So you try and use it, it trips on circuit on the way down, and the other on the way back up.. Might not be right on the money on this one, but I bet its something close to that.