Yeah so true pass-through charging would allow the device to function even if the battery is completely fried, or possibly even removed. It's a really solid idea for a device without a removable battery to have that feature, bringing much longer-term value to the product. As USB-C can carry so much power it creates interesting use cases. It can easily replicate batteries with headroom for charging. I've run units with a USB-C PD triggered at 12V converted to 4.2V, for up to 60-100W it is cheap and simple to do. No more sagging power rails and still portable-ish with battery banks.
My thoughts are that if pass-through charging is the case here with Nano, turning the heat cycle on with the charger plugged in might increase the load on the USB lines by the full wattage of the normal operation, because the power going to the battery charge will be added to or regulated with the power drawn from the heater. It will require circuitry to bypass the battery to supply inlet power on demand to the heater. Hence the term pass-through? Normally a term used for battery banks or laptops etc. when they can accept a charge and simultaneously charge something plugged into them.
If there isn't a difference of charge current on a powered up Nano, then the battery is just running the heater whilst charging, that isn't true pass-through, it's just charging.
And that 'use while charging', despite being a typical no-no for battery health/longevity, for this device I think it will be both useful and not as big of a deal as with other more expensive units. Definitely not ideal, but it's great not getting stuck in the present by creating only a small cost in the future. If nothing else it is a good discovery and handy to know about.
For my expected usage, it will be really useful if, when plugged in, it does indeed operate immediately after going flat and showing red lights and refusing to function. 'Use while charging' is a good feature for a cheap and occasional EDC type ultra portable. I know I'll forget to charge it ready a lot of the times it's going to be wanted. It might be flat atm.
Because of the 1000mAh battery and run time, I assume this is pulling something like 30-60W max. which is a lot of current at 5V, so I think it's more likely that power will always be pushed from the partially discharged and charging cell. And when I test I expect to see the charging current remaining fairly constant despite the heating cycle.
But, there is every chance for some interesting USB-C trickery.
However, given the price and recommendation of using a 5V1A source for charging. I think that's telling that whatever BMS is in this thing it's only fairly basic.
But that's what I like about the V3 Nano, so far it seems to be this really nicely considered basic vape. You put herb in, you click it on, wait for a while, and just let it do its thing, which it just does.
If it does that thing as soon as I plug it in when it reports being 'flat', that's a win in my books.
If it does the thing in several years if plugged in when the cell is old, decrepit and ballooned, it's still a problem to get the battery out, and for landfill.
As for performance with this thing, it's a pretty nice little unit. I took it out the other day to use on my way home. The next day I took the TM2 with pill cooling stem.
The Xmax took a lot longer to do the thing but it did do it.
The TM2 was fast and effective, definitely more so, but at 7X the cost.
The Nano really shines against a dynavap, where it's maybe more inline with that signature wlthout the manual heat up. And it gets hotter as you go, for longer, while vapcaps begin cooling immediately. Stealthy to boot, a nice subtle out-and-about unit.
The filling/emptying isn't nearly as clean though. But it's no slouch. I've given away my V3 Pros, I think the Nano suits me better but the Pro is the better unit. But it does give me the same performance that got me buying a second V3 Pro so I could claisen adapter them up.
Ultimately my preference is for a rapid and thorough high temp blast, where the TM2 has saved the day. But actually the more mellow style is still ample and unless you're already stuck on higher temps it is practically a viable option. And it's fairly warm at 220°C, ABV is a touch beyond tan but still far from scorched.
I like that it's so small and simple, has a nice bowl size, and performs gradually and effectively.
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