When you say get the battery to a low state, do you mean to 30%, at the Low Battery Warning? Or do you mean even lower than that?
I meant Low Battery warning that kicks in at 15 miles of range left. I usually drive a few miles at this point to get home. I never got below that (like in turtle mode) , it would be too daring. Interesting observation, I usually disable Eco mode at low battery and drive it like I stole it for a few miles, because of I know I could get home just in time. Try to go accelerate uphill in Eco mode and then half way turn off Eco mode. It would create an effect like somebody drops a sledge hammer. There is no way you can modulate this quickly with accelerator, the Eco On/Off is instant. This help to remind me this car is no slug at all. So when you get home with less than 15 miles left, let it sit for a while - this will allow cells to rebalance in low state. I plug the L2 charger, but charging (timer #1 configured this way) starts at 1:00AM and stops at 6:00AM. Someone also mentioned after this low to 100% charge cycle, let it sit for a few hours and then re-connect charger to top it off to complete the cell balancing.
There was a discussion how to keep battery healthy for a long time and there was one post about how one owner keeps battery in good shape for long time and this was suggested. Unfortunately, I could not find this post, but just remember the procedure. Anyway, being a mechanical engineer, I found it very reasonable suggestion. This is not every charge cycle, it was suggested to do it once every 2-3 month. I would do it when opportunity presents itself, so 2-3 month is plenty time to catch those moments.