The Skystar is my first Aspire mod that has a battery meter. I previously used a few iPV single battery mods and when the battery meter reached 50% I noticed the heat and flavor was less. So it was just habit for me to remove the battery at 50% charge and put in a new battery. Now with the Skystar once the charge got to 50% I would remove the batteries out of habit, but now I'm noticing that I can use the batteries past 50%, right now the meter is at 25% and I still get good heat and flavor. I guess what I'm wondering is if the battery meter represents actual battery charge, or is it a countdown to when the battery should be charged.