power bank as ups

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wle
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power bank as ups

Are there power banks (portable battery powered USB supplies) that can be used as a UPS?

The problems are:
1. some require a button to be pressed, to start the output
2. some assuming they are ONLY charging a battery and may quit supplying current when the load falls below a threshold

I think the key word is “pass-through”, that is supposed to mean they can charge and discharge at the same time

But they would also need to satisfy 1. and 2. above..

(What is the use? USB powered cameras, for instance, for security systems.. internet routers. (so you still have a phone if your phone is via internet).

So instead of powering via the regular USB 5V supply, you would use one of these things instead.

Would also be nice if they were cheap.

I’ve seen things on Amazon in the $40 range, that is too much.

wle

e1000
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They do exist, although not very popular.

https://www.amazon.com/dp/B013JHYQNC/

There are also USB power banks that have passthrough charging function, although it’s not very widespread and not always advertised

wle
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yeah $125 is a lot
i was thinking more like $25

wle
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i see this for $6

https://www.amazon.com/Simpiz-5000mAh-portable-charger-external/dp/B015H...

seems like it would work

if you don;t need a lot of mah

e1000
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There you go. Like I said, they do exist, even in lower priced banks, it’s just not a widely implemented or advertised feature.

Scallywag
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They make things like this but I haven’t tried harder to find one in-stock somewhere. Battery backup for a small device run off an 18650.

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wle
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so i have a liitokala engineer charger

it occurred to me that it has a usb out, powered by cells that are in the charging bay

it doesn;t work as a UPS for 2 reasons

1. load has to be OVER X ma, and X is like 50 or 100

2. it does not work when wall-wart power is active

so it would not continuously supply 5V in either case

wle

BT100
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Does anybody know of any powerbanks with pass-through charging?

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The TP5100 chip used in the BLF LT1 lantern for charging can input/output at the same time. In fact, the lantern will be able to work without batteries if a power supply is plugged into the USB charging port.

Here is a simple charging board available on eBay which uses the TP5100 chip.

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will34
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BT100 wrote:
Does anybody know of any powerbanks with pass-through charging?

I think the gen2 xiaomi 20,000mAh have 5V pass through but not sure if there is a switching
when input power is disconnected. Most UPS doesn’t have switching but DIY solar controller + 12V battery charger 2in1 does. I can check it out and let you know which powerbank in my collection have non-switching pass through (always on or separated buck-boost controller).

BT100
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@ Will34,
Thanks, would appreciate that!