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Is there a UPS and lithium ion battery combo that works on the raspberry pi 5? I have looked around, but I can only find information on the RTC clock battery.

I know the voltage and ampere output for the rpi 5 are not the same as as for the rpi 4, and I can't find out if existing addons are compatible, and if not: are there options out there that work for the raspberry pi 5?

I am new to tinkering and this would be my first try to hook up a raspberry pi with a battery power control / UPS element. If I'm asking something stupid, or haven't asked something relevant. Feel free to share!

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Is there a UPS and lithium ion battery combo that works on the raspberry pi 5?

I'm sure there is, but the rules here on SE prohibit "shopping requests", so I'll leave that research to you. Instead, I'll try to answer your question by giving you some requirements for such a UPS.

RPis continue to increase their input power requirements, and the RPi 5 did not break that tradition. The "official" power supply for the RPi 5 is this 27W unit; 5.1 V at 5 Amps.

But this 27W requirement may not apply to your situation. The 27W specification is based (mostly) on:

  1. power for the RPi 5
  2. power for the USB peripherals

So - if your situation/use-case does not require heavy USB peripheral use, you may get by with a smaller UPS requirement. Your first step then, is to determine exactly how much power you need from your UPS, and how long it must support the RPi 5 at that power level.

The how long part will determine how much battery capacity you need, and this is the essence of sizing a UPS. For example, if you RPi power requirement is an average of 10W (5V, 2A), and it needs to operate from UPS power for 30 minutes, your base energy requirement is 5 W-hrs. Let's reflect that onto the battery; it means that the battery must have a rating in excess of 5 W-hrs - the excess is required to allow for losses in the system, dynamic battery characteristics, etc - all the "losses" in other words.

You'll find that batteries are typically rated in units of amp-hours or milliamp-hours. This rating is at some nominal battery voltage. For example, a Li-ion battery has a nominal voltage rating of 3.8V, so that can be converted to W-hrs by multiplying the amp-hr rating times the voltage. For a Li-ion battery with 2500 mA-hr rating, that equates to:

2.5A-hr * 3.8V = 9.5 W-hr

Now, you'll need to burden the battery to also carry the inefficiency of the system components. Let's assume that is a 25% burden, which means that your battery W-hr rating is reduced by 25%, or:

W-hr Rating = 9.5 W-hrbattery * 0.75 = 7.125 W-hr

So - that's the procedure. It's easy if you keep the concepts of Power and Energy clear in your mind: Energy is Power applied over Time.

Finally, if you're DIY-inclined, or if you can't find a UPS that meets your specs, this article may be of interest to you (disclaimer: I've not read it!)

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Is there a good UPS commercially available?
At the moment I am not finding any. Even PiJuice seems to be rare and I am unsure if PiJuice is suitable for the RPi 5. Running a RPI 4 or 5 without a UPS is asking for trouble in an environment where the Power Supply is unstable.

OK, I suppose given time I could build one myself...but time...!!

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  • If you have a new question, please ask it by clicking the Ask Question button. Include a link to this question if it helps provide context. - From Review
    – jsotola
    Commented May 2 at 21:08

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