Since I have such a hard time finding that info again, apparently it's a very minor effect, since no one really bothers to do studies or talk about it much. Most of the concern is with charging too fast, rather than too slow. And using 15 amps is still 3X faster than people who are trying to turn it down as low as it will go at 5A, so I wouldn't worry about that much.Nuts, I may be killing my battery. I *mostly* charge DCFC at the free CHAdeMO in town. But I also charge off my solar panels, and in order to not pull from the grid when I charge I plug into 120v and drop the amps to 12-14. Saving money on free charging and eating my 3yo battery alive...