I always carry 2 around.
I've been wanting to find out if I should drain my batteries completely before charging them, or if I should keep them near 100% at all times. Are you saying that they will last longer if I do the latter?
For long term storage it's best to keep them at half charge..otherwise charge them and use them..you don't have to wait until it's completely depleted with lithium batteries to charge them. I usually charge mine when they are dead though.
What I was saying is when using small batteries you will get more time out of them if you don't use one constantly. If you have 2 use one for awhile then use the other and keep switching them throughout the day. I puff on one for awhile then switch and I've found if I don't use any 1 battery for a long time they last a lot longer before they need charging.
I used to think it was best just draining a battery out and switching but found it's better to switch. It's really easy for me though as I use at least 7 different flavors a day and keep them ready to vape..so I grab one flavor puff for awhile when I want a change I grab another. When I'm out and about I usually just stick at least 1 auto in my pocket and a couple eGo's with different flavors in them.
I use a lot of different devices 5-eGo's, 2 auto mega 510's and my VV Tube. I only find myself charging 1 of the tube batteries every 2 days and I charge the autos maybe once a day. I charge an eGo or 2 a day (some days none and some 3 though).