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1. Embed this notice
   Rich Felker (dalias@hachyderm.io)'s status on Monday, 17-Feb-2025 05:39:31 JST Rich Felker

   Lazyweb, is there any decent DC-DC UPS (no inverter) with USB PD outputs up to at least 20V & 65W profile?

   • Embed this notice
     Rich Felker (dalias@hachyderm.io)'s status on Monday, 17-Feb-2025 05:41:31 JST Rich Felker

     in reply to

     Found a powet bank by "CUKTECH" 😂 that looks like it'd almost work but only 45W (not a problem) and 15V (problem, I need 20).

   • Embed this notice
     Brian Campbell (unlambda@hachyderm.io)'s status on Monday, 17-Feb-2025 05:42:55 JST Brian Campbell

     in reply to

     @dalias The usual term for these is USB power bank, and yes there are power banks that meet those specs and more: https://www.anker.com/products/a1340-250w-power-bank?variant=43739694465174

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     Rich Felker (dalias@hachyderm.io)'s status on Monday, 17-Feb-2025 05:44:48 JST Rich Felker

     in reply to

     • Brian Campbell

     @unlambda Power banks have lots of problems like often not supporting passthru or renegotiating and power cycling your device every time input power status changes. That's why I specifically said uninterruptible.

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     Rich Felker (dalias@hachyderm.io)'s status on Monday, 17-Feb-2025 05:46:16 JST Rich Felker

     in reply to

     • Brian Campbell

     @unlambda Also, $180 price tag is absurd. I could build this from about $15 in parts excluding batteries.

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     Rich Felker (dalias@hachyderm.io)'s status on Monday, 17-Feb-2025 05:49:45 JST Rich Felker

     in reply to

     • Brian Campbell

     @unlambda Cheap 65W buck based PD modules $3 each, BMS $12. Might also want a boost module to avoid needing >20V input & 7S pack.

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     Brian Campbell (unlambda@hachyderm.io)'s status on Monday, 17-Feb-2025 05:50:09 JST Brian Campbell

     in reply to

     @dalias Hmm, fair enough, I guess I usually use them for either extending the range of things that already have batteries, or things that I don't really care if they power cycle. I have used my power banks on passthrough power before without noticing any issues, but as mentioned it was nothing critical.

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     Rich Felker (dalias@hachyderm.io)'s status on Monday, 17-Feb-2025 05:51:23 JST Rich Felker

     in reply to

     • Brian Campbell

     @unlambda I need it for modem/router, which has no battery.

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     Rich Felker (dalias@hachyderm.io)'s status on Monday, 17-Feb-2025 05:51:42 JST Rich Felker

     in reply to

     • Brian Campbell

     @unlambda And the fucking ISP provided thing uses USB C in but won't accept anything that doesn't give 20V, so none of my existing banks will power it.

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     Wanja (muvlon@hachyderm.io)'s status on Monday, 17-Feb-2025 08:41:25 JST Wanja

     in reply to

     • Brian Campbell

     @dalias @unlambda Yes, I am in a similar pickle because I'd like to power my Odroid H4 home server and I tried all of my power banks already: None of them support passthrough :/ Neither the cheap generic ones nor the nice brands. It seems like a really boutique feature, even though it wouldn't be that hard to provide I feel.

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     Rich Felker (dalias@hachyderm.io)'s status on Monday, 17-Feb-2025 13:15:22 JST Rich Felker

     in reply to

     Hmmm... there's a module based on SW2303 negotiation IC & PL5501 DC-DC that looks promising. Any idea if that's gonna be a real boost that can output 20V from lower input voltage or if you need to supply it over 20V for full output coverage?

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     Rich Felker (dalias@hachyderm.io)'s status on Monday, 17-Feb-2025 13:17:37 JST Rich Felker

     in reply to

     If that module works with low voltage input, car battery and trickle charger would make a full UPS out of it.

   • Embed this notice
     Brian Campbell (unlambda@hachyderm.io)'s status on Monday, 17-Feb-2025 15:02:21 JST Brian Campbell

     in reply to

     @dalias OK, after digging around a bit to verify that things are properly uninterruptible and support passthrough, I found https://voltaicsystems.com/v88/

     A bit big and not cheap, but it looks like it meets all your requirements. They have smaller/cheaper ones but that don't support USB-C PD or not up to 20V.

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     Rich Felker (dalias@hachyderm.io)'s status on Monday, 17-Feb-2025 20:48:25 JST Rich Felker

     in reply to

     • Brian Campbell
     • LisPi

     @lispi314 @unlambda I also want the output & battery/input sides separate because I don't trust the companies making these things not to have the two sides talking in stupid ways that breaks the "uninterruptible" property. 🤦

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     LisPi (lispi314@udongein.xyz)'s status on Monday, 17-Feb-2025 20:48:26 JST LisPi

     in reply to

     • Brian Campbell
     @dalias @unlambda That's been my general though about a lot of those larger power stations.
     
     Unfortunately I am somewhat wary of screwing up if I DIY. I'd *still* prefer to use either sealed lead-acid, LiFePO or something else less fussy than lithium-ion.
     
     Most such power stations seem to *insist* on using lithium-ion which isn't cool.
   • Embed this notice
     Rich Felker (dalias@hachyderm.io)'s status on Tuesday, 18-Feb-2025 01:26:28 JST Rich Felker

     in reply to

     This looks potentially appealing as a closed box finished product (except the battery, easy to do separately): https://www.aliexpress.us/item/3256808213097600.html

   • Embed this notice
     RealGene ☣️ (realgene@hachyderm.io)'s status on Tuesday, 18-Feb-2025 01:48:42 JST RealGene ☣️

     in reply to

     @dalias
     Yeah, I'm going to trust a $1,500 phone to this...

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     Rich Felker (dalias@hachyderm.io)'s status on Tuesday, 18-Feb-2025 02:09:30 JST Rich Felker

     in reply to

     • RealGene ☣️

     @RealGene Any decent device is not going to care about faults that might deliver full voltage. It's prepared to convert the full range to operating & cell charging voltages and just requests highest it can get for more power over the current capacity of the cable.

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     Rich Felker (dalias@hachyderm.io)'s status on Tuesday, 18-Feb-2025 02:11:37 JST Rich Felker

     in reply to

     • RealGene ☣️

     @RealGene And hey, DykRadio sounds marginally better than CUKTECH. 😂

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     Rich Felker (dalias@hachyderm.io)'s status on Tuesday, 18-Feb-2025 04:15:11 JST Rich Felker

     in reply to

     • RealGene ☣️

     @RealGene Looks like vs the SW2303/PL5501 modules though this lacks boost, so needs 24V input. So it's like a worse version of 2 of those modules packaged together, for higher price...

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     Rich Felker (dalias@hachyderm.io)'s status on Tuesday, 18-Feb-2025 04:57:12 JST Rich Felker

     in reply to

     • RealGene ☣️

     @RealGene OK, ordered a couple of these modules. https://www.aliexpress.us/item/3256804201390760.html 🤞

     I'll try powering modem with one and see if it works, and add battery once I confirm what voltages it accepts. Even if not, it should make a great phone charger or even laptop power supply. 🤷