Does being in ECO Mode (button pushed) in and of itself, use more battery (reduce the charge of the battery) faster/more quickly than being in Normal Mode?
Others correct me here, but I'd say no. ECO only dampens throttle response in the 1st half of gas pedal travel. In fact, since it also reduces AC priority, it will reduce current draw there. The RESULT may be more current draw if you use ECO to help maintain EV propulsion. Better use of ECO is to maintain EV GLIDE, which uses very little or no current. I don't think ECO really says "Use more battery." Just "Assume I didn't adjust throttle input quite so much."