My new Seidio 4000 battery will be here tomorrow. What is the best way to train it? Powered off, insert, full charge, turn on? How long past the point when the led turns green?
Or can I just plug in and play while it charges?
It is my understanding that LiPo batteries don't need to be "trained".
Past 4.2 VDC its chemical properties are prone to overheating and possible combustion. Your battery has circuitry that attempts to prevent that. Your phone's charging algorithm also will prevent that by shutting off the charge and letting the battery drain and charging again.
Discharging below 2.5 VDC, the battery may not ever hold a charge again. Just the nature of the LiPo. So it is not recommended to aggressively discharge the battery for "training" purposes.
LiPo's nominal voltage is 3.7 VDC. That means it likes to be in that range. So, the more times you reach that range, the better it is for the battery. That means frequent partial discharges are best.