These are very small sizes compared to a whole-house system or even one that could run my servers for 24 hours, but the NMC power bank could easily start a house on fire,

Can I ask if you've acquired a battery fire blanket or box that you could use in an emergency for your smaller packs?

and the LFP units could easily fill the room with highly toxic smoke.

This is my concern for my situation. Not only is the vapor produced highly toxic for inhalation, but also a very high concentration of hydrogen (35%-55%). I'd thought about trying to build in a ventilation system that I could engage, and then a follow-on detection system that could trigger the vent to run, but with that high a concentration of hydrogen, I'd be worried about the vent fan or relay igniting the hydrogen from a spark.

So today, I too and using the YOLO method. I've purchased really high quality UL 9540A Compliant LFPs, but that only goes so far.

In wildfire prone areas, a burning shed might be even a larger liability not only to the residence but also hundreds or thousands of homes in the area.

These are very small sizes compared to a whole-house system or even one that could run my servers for 24 hours, but the NMC power bank could easily start a house on fire, and the LFP units could easily fill the room with highly toxic smoke. YOLO I guess, but I'm definitely keeping an eye on battery development, and very excited for sodium-ion to become widespread.

(BTW, a big concern from LFP batteries in thermal runaway is that they can produce enough carbon monoxide to very quickly become life-threatening in enclosed areas... the risk of fire is less but the risk of being poisoned if there is an event is higher.)

At one time I was set on building out a large commodity 48v rack of LFP batteries for "big and cheap" storage of my excess solar power (instead of exporting to grid), but the cheap batteries are a wildly different in safety with no apparent way to know if you're getting a good safe system or a time bomb waiting to happen.

I've got 10KWh of high quality Enphase LFP batteries in use now, but scaling these expensive dedicated integrated solar batteries is very expensive.

I've been progressively downsizing my self-hosting stack, it's now all "1-liter" PCs with 35-watt CPUs and a couple tiny ARM boxes... that's a start, but at my budget I would probably need power banks that can automatically switch to the grid once exhausted to start powering my setup from solar. Or DIY some kind of power-switching solution on a little box that monitors the charge status of the power bank.