[jtriangle]

I have little battery dock things, really dumb devices, but, USBC goes in, battery docks in, and it slow charges in about 8 hours. I've got 3 of them.

Also if you're talking about the world being dark for 3 years, not sure batteries are the thing to stock up on friend. We'd be well into mad-max mode after a few months I'd think, and after a year or so of that, well, nothing's going to come back for a good long time.

I'm much more concerned with making it, say, a week without being able to charge, which, I can easily do without thinking too much.

[evilduck]

I can also go several weeks off grid with literally any phone, a moderately sized power bank and a 40w solar panel hanging off my pack or over a tent without thinking too much. It's far more versatile for powering other devices and I never have to reboot my phone. If you want to carefully buy stuff you can even get a fully IP65 rated or better setup, which makes it actually survivable to the elements.

I can't see how juggling internal batteries is anything but the worst possible option. I can upgrade or replace any one component without obsoleting the rest. How many future phones will accept your stockpile of batteries?

[Terretta]

> if you're talking about the world being dark for 3 years, not sure batteries are the thing to stock up on friend

Friends don't let friends go camping with a bag full of replaceable phone batteries.*

A couple alternatives I like...

This costs considerably less per milliwatt-hour than even ~$20 replaceable phone batteries, and is rather more useful camping:

https://www.amazon.com/Anker-PowerCore-Portable-Retractable-...

If one needs more oomph, this is 6 lbs, so I wouldn't take it for a walk. Depends on the type of camping:

https://www.amazon.com/Anker-Portable-Generator-Traveling-Em...

For the little bank, something like Anker Solix PS30 Solar Panel charges like a wall wart with just a couple hours' midday sun in northern U.S. or southern E.U.:

https://www.amazon.com/Anker-Foldable-Resistance-Ultra-Fast-...

North of 40th, combo can get us through strings of rainy days off grid while not thinking about it.

To cost less, on Alibaba you can match case style, plug placements, and feature/functions to find the same OEM models as well-known portable power and solar brands for a fraction of price if one doesn't mind ship time.

* That said, this is all one's power eggs in one power basket. To your point, a bag full of batteries means one can fry half a dozen and still have a few juicy eggs to suck dry, but don't lose tools or phone bits and bobs on field replacements and one will still want a panel or two to top them off!

[jtriangle]

Sure sure, and I lose the ability to keep a phone going 6+ years because the battery is glued into the case. So I'm making 3x the e-waste for... really nothing honestly.

In terms of power banks, I'm currently hoarding my friend's disposable vapes which all have fairly high output LiPO batteries in them. All I need once I'm done harvesting is a few 3D printed parts, a aliexpress BMS, and some wiring, and I'll have way more capacity than I know what to do with for very, very cheap. BMS is the most expensive part really, the rest is a few bucks, and, if I kill a cell, well, there's an abundance of disposable vape batteries available.