This is cool. But now I want a power bank with hot swappable batteries/modules. Or better yet a connector that you can attach multiple power banks to and it gives power if at least one non-empty powerbank is connected.
> But now I want a power bank with hot swappable batteries/modules
I think it’s possible to build one. Get a bunch of 18650 cells from a reputable brand (or just an old laptop battery, if you’re brave enough), then look for a 18650 powerbank kit on AliExpress – some of these would be with slots you can just plug the cells into, without welding/soldering.
I'll elaborate. You'd think that by putting N powerbanks daisy chained together (except i imagine at either end) you get ~N times the mAh or runtime but i think you get probably .25N or less. the "last" powerbank in the chain, the one you'd charge to charge them all, would run out of power first, and about 15% of seconds more afterward, the second one, then the next, with the "first" powerbank, the one you're using for its USB ports to power a load lasting about 2x as long, no matter how many powerbanks you put in a row.
this is a supposition, but i don't think the numbers are very far off. Most powerbanks are 18650 or 26650 inside - flatter or "better" ones are lifepo or lipoly or whatever, instead of cylindrical Li-Ion. anyhow those are 4.2V nominal and USB wants 5V so all single cell or parallel'd 18650/26650 power banks are going to use a boost converter to get the voltage to 5.1V nominal at the USB terminal (assuming a dumb power bank, a power bank with power delivery will boost that even higher but also probably has multiple batteries in series, but that doesn't matter, it makes efficiency worse for our daisy chain regardless!). So these boost circuits "charge" something and store it until there's the correct number of electrons to equal whatever charge/joules is required to run the load. There is >15% wasted as heat either in the capacitor or the inductor (depending on the style of boost converter). There's another ~15% or so lost in the charging circuit, as it has to take 5.0VDC in and run a charging circuit (similar to mppt) on the battery at different voltages and/or amperages which again waste is generated as heat. Cable losses in the daisy chain probably account for a percent or two each, the indicator lights across all the power banks, plus all the microprocessors/etc inside of them probably waste another couple percent.
You'd lose a lot in efficiency. A power bank designed for this would have 2 cables and 1 or 2 wires, power transfer cables and sense/control wires. My engineering brain says "don't do this it's stupid and I think OP was making a joke I don't get"
There are a good amount of lower power ones (e.g. with an N100 CPU) that draw ~15W usually and not that much more at full bore, and some of them are starting to come with USB-PD power inputs (even if they come with a DC power adapter some will accept USB-PD on another port).
i have a passively cooled Quieter 4C [1] with N100 and a 4TB [dram-less] nvme [2] and it draws 4.5W total at idle running EndeavourOS w/ KDE Plasma. at full load (Handbrake 1440p transcode) it draws ~10W.
i left it at stock bios settings and did not put it into higher TDP mode though, since i use it as an htpc and it mostly idles, i'd rather it stay at more comfortable operating temps.
the nvme cost me more than the pc, which for $207 includes 16GB ram, 512GB nvme, and a Win11 Pro license. insane.
i'm mostly converting 4k from a phone to 1440p and cutting [backup] storage by 6x. most of these vids are < 3min, and i can do quite a few in a batch job overnight. im in no rush. it does about 4fps with the 1080p30 HQ preset with the only additional change to up the res to 1440p. i would not use it for batching feature length films, but you can do one in a pinch :D
I've wanted this for ages, Laptop ergonomics are horrible. When traveling I use a portable monitor, keyboard, mouse. Yes it's annoying to travel with all that but worth it not to end my work days with neck pain and a migraine.
I need a somewhat powerful GPU for work, so I'm seriously considering buying one of the more powerful handhelds with removable controllers and just taking them off. The screen would be superfluous but it's probably the most powerful travel PC, at least for the price, that's available right now.
I don't even need the battery that much. But all the options I've seen for SFF PCs that would fit in a backpack look fragile and I wouldn't feel confident carrying them around often. Plus, they're either expensive (because it's a tiny market) or geared towards office work.
On the other hand, the Mac Mini exists and is exactly what I'd want in terms of hardware. Why don't us Linux/Windows folks have this option?
Plenty of NUC hardware is pretty beefy, most more tough than most of those gaming handhelds. I've dropped a couple of Intel NUCs down concrete stairs and they only got a few scratches. They've also had really good Linux support for ages, and had Intel's Iris Pro GPUs for a while. Unsure they'd really fit your needs though. AMD sells a number of APU boards though, they've got modern GPUs. Still not breaking any benchmarks though.
Also, those gaming handhelds are pretty power and temperature limited. They're often a good bit less powerful than a halfway decent gaming laptop, just a more convenient form factor for portable gaming.
What you'd want is a NUC with AMD. With an iGPU of 780M or higher, you'd equal or beat a Legion Go. You'll find plenty of NUCs like this from Beelink, Minisforum, etc. Usually at $400-800. Depending on sales.
Intel's Lunar Lake is another option. The iGPU on that line will match or exceed a Legion Go too. Right now, it's mostly in laptops but some NUC models have been announced.
> I've wanted this for ages, Laptop ergonomics are horrible. When traveling I use a portable monitor, keyboard, mouse. Yes it's annoying to travel with all that but worth it not to end my work days with neck pain and a migraine.
Have you considered dropping the portable monitor for an angled laptop stand that will elevate the screen to eye level? I've got one that collapses down small enough to fit in a reasonably deep pocket.
I do actually use the laptop as a second screen in this way most of the time. However, it's amazing how many hotels lack any table deep enough to place a 15" laptop on a stand with a keyboard in front of it.
Fwiw, with my 15", unfolding flat and standing vertical, with keyboard etc in front, gave a plausible screen position. So I just kludged vertical-ish stands (and fretted over an eventual tip and crash). I considered hanging a portable monitor off the side (brick of a thinkpad, accustomed to gaff taped extensions), but didn't get to it.
I have one and my main gripe with it is how large the power brick is. It's practically like carrying a second mini pc; I didn't take this into account when I got it, lesson learned.
considering https://streacom.com/products/nano160-fanless-psu/ stuff like microPSU, miniPSU, and nanoPSU exist, this is unacceptable. I've used these mini PSUs - which are a barrel power jack, a hdd molex power cable, and the N pin ATX plug on a breadboard the rough size of the N pin ATX connector from large PSU - in remote inaccessible locations to do "in box UPS" for vm hypervisors on intel atoms/celerons and the like. Plug this in to the board, wire in a 12v stamped aluminum PSU that takes a battery as backup (used to be like $22 on amazon) and a SLA battery, toss that in one of those "mini desktop" cases - not the elitedesk - like the ones you saw in every office 10 years ago.
anyhow you can get a 12V PSU that does whatever amps (12? 15?) in a pretty small formfactor, and the "additional" stuff the motherboard needs is, as shown above, insignificant. The PSU can be pretty dirty, as in in the US do literal 10:1 winding to get 12V out (i know it'd be slightly different winding amount to account for losses in rectification and lines and whatnot but 10:1 looks nice to the math) and rectify it straight into one of those nanoPSUs. believe me i've seen me do it.
also don't ask to see my laptop DC-DC supply for running straight off a solar panel... it's larger than most NUCs, too. oh wait, you still need a laptop brick, plus the DC-DC. So you gotta DC-DC -> DC-DC -> laptop which -> DC-DC and probably DC-DC again (1.2v/3v3 rail probably clocked off 5v rail, that's what i'd do naively)
those "dashes" in "DC-DC" are doing a lot of heavy lifting
Yeah they look good. Unfortunately from what I've seen they have limited availability outside of the US and EU. I could probably get hold of one but not sure if they'd cover the warranty outside of their sales area.
"not very power efficient" -- definitely some of the most power efficient x86 machines you can find today. Until the latest generation, Ryzen APUs provide better performance with lower power consumption than Intel ones. And you can lower CPU frequency if you want -- even at base frequency, they run fast enough for everyday tasks with fan almost completely quiet. Of course this is oversimplifying things a bit.
There is a bunch of AMD-based tiny boxes for under $1k, and fancier boxes from HP or Zotac with discrete NVidia GPUs for $3-4k. They are somehow larger than a Mac Mini, but still very much the form factor of a small box to push into a backpack.
For their CES coverage they said they used MacBooks. They just also brought a Mac mini along that they hooked up to fast internet in a nearby e-sports venue that they used as a backup option to remote into and edit videos from.
They don't, but they do idle as low a 4W for the whole system[1] so running one off a large portable battery would be possible (if not exactly elegant).
You'd need a battery with UPS-like functionality (and doesn't beep when it's taken off power), otherwise every time you plug and unplug it your mac would restart.
Which is surprisingly hard to find for a portable (usb-C) battery.
I assume they meant why is the power interrupted if it switches from charging to not, and I believe the answer is "it's cutting from just vampire tapping the incoming power to feed outgoing, and it would need either chunky capacitors or to be constantly wearing on the battery to not do that".
For gaming, I'd also rather have the Steam Brick, I think. You have a large company with strong interest in the drivers for built-in hardware and external controllers all working smoothly. We also know video over USB will just work. And USB-C power so I don't need a barrel connector to travel, not sure where NUCs are at on that one.
I could accept Pi, with case, storage and battery in single enclosure. That is singular unit with relevant ports open to use and it being usable while charging.
It's hard to tell with a lot of NUC style devices whether they support USB PD as the device being charged but I would much rather have one or two USB power banks as my battery/UPS for the NUC, phone and laptops than anything more specific or inverted up to mains, etc.
