Ask Lemmy
A Fediverse community for open-ended, thought provoking questions
Please don't post about US Politics. If you need to do this, try [email protected]
Rules: (interactive)
1) Be nice and; have fun
Doxxing, trolling, sealioning, racism, and toxicity are not welcomed in AskLemmy. Remember what your mother said: if you can't say something nice, don't say anything at all. In addition, the site-wide Lemmy.world terms of service also apply here. Please familiarize yourself with them
2) All posts must end with a '?'
This is sort of like Jeopardy. Please phrase all post titles in the form of a proper question ending with ?
3) No spam
Please do not flood the community with nonsense. Actual suspected spammers will be banned on site. No astroturfing.
4) NSFW is okay, within reason
Just remember to tag posts with either a content warning or a [NSFW] tag. Overtly sexual posts are not allowed, please direct them to either [email protected] or [email protected].
NSFW comments should be restricted to posts tagged [NSFW].
5) This is not a support community.
It is not a place for 'how do I?', type questions.
If you have any questions regarding the site itself or would like to report a community, please direct them to Lemmy.world Support or email [email protected]. For other questions check our partnered communities list, or use the search function.
Reminder: The terms of service apply here too.
Partnered Communities:
Logo design credit goes to: tubbadu
view the rest of the comments
Or, I mean, it could just wire all the positives together and all the negatives together and hook that right into your target device.
It'd be the same output voltage regardless. A little less internal resistance, and lower step down in the later phases, but neither should make a difference in what you're powering.
Kinda like how there were those converters for the GameBoy back in the day that let you put C batteries into it. Same principle.
It's probably not possible to do that safely because USB power supplies aren't just dumb batteries. They actively communicate with the device receiving power about how much current the device wants, and should only supply 500mA if they fail to do so.
USB-A ports aren't supposed to receive input power, which is effectively what would happen in that arrangement after a powerbank shuts off to prevent over-discharge of its batteries. The resulting behavior is, as I recall unspecified and might result in damage to the powerbank. Worse, it could interfere with the over-discharge protection and damage the batteries. Charging damaged Li-ion batteries is bad, where bad may include fire, explosion, and/or emission of toxic gas.
Yeah, I should work on my reading comprehension.
I deff read the prompt as having a bunch of rechargeable AA style Li-ion batteries, and how to utilize them without having to swap out to a new pair or whatever.
Deff don't want to do this with a bunch of disparately sized smart batteries providing power over USB. Very different problem.
Thank you for the great reply!
You can still just crack open the banks and wire the cells together in parallel or series (depending on your needs), then hook them up to one of the controllers. I bet they're just a bunch of 18650s
Sure, but you probably shouldn't build a DIY battery pack out of salvaged 18650s of varying brands, capacities, and conditions unless you really know what you're doing because that's dangerous if you get it wrong.
So I could actually get a couple of old short usb cords together cut the ends off, strip the positive and negative wires and hook them in series without it changing the output voltage?
No...please do not do this.
The voltages of the output ports are probably not all exactly the same and you could end up damaging the device (or worse, starting a fire). They MIGHT have reverse current protection on them, but I've seen some pretty sketchy power banks.
You can't just wire them in parallel. USB has communication pins that help boost circuits in the battery change voltages levels. Even if it all works, you're going to get extremely poor charge times.
I don't believe it's out of the realm of EE to design something that allows you to plug in multiple power banks though, but I've never seen any
The fact that you're having to ask means you shouldn't do it.
You need to take a minute to research before you burn your house down.