
Basically, this. IMHO this doesn't make them "better".
I've used both box and tube shaped mods; I prefer the tube form factor because it is more comfortable in my hand and fits easier in my pants pocket.
Let your internal box mod battery charge dies out, and you can't vape unless you have your charger and a wall socket nearby. Let your external tube mod batteries die out, if you carry a couple of spares with you you can continue vaping.
I've used mods that use either internal batteries (box mods) or external batteries (tube mods). I prefer external batteries because I get to choose exactly which batteries I use and not depend upon the manufacturer's choice (who IMHO doesn't necessarily know which battery is better or safer).
The internal batteries used in most box mods are LiPo chemistry -- not a safe chemistry. These depend upon the protection circuitry of the mods' chip to be safe to use. The external batteries used in tube mods are IMR or Li-Mn lithium batteries -- a safe chemistry which don't go up in flames or explode when they short out.
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The internal batteries in box mods are not replaceable, so when the battery dies the entire mod will need to get thrown out. The external batteries in a tube mod can be replaced inexpensively, costing only $5 - $10, last 1 - 2 years, and allowing the owner to continue to use their expensive mod.
That's my
Advancing Up the Vaping Ladder
Battery Basics for Mods