MakerFocus Raspberry Pi 4 Battery Pack UPS, V3Plus Expansion Board with 10000mAh Battery, Type-C Interface for RPI 5 4B 3B+ 3B 2B+

I replaced their original version 1 UPS with this new V3P version. It cleared all of the low voltage warnings I have always gotten with the V1 circuit. My Raspberry Pi 4B is loaded with a 4-Port USB to RS-232 Serial Adapter Hub, two RF wireless USB mice, and its Pimoroni Fan Shim cooling fan. Running OpenCPN navigation program, no problem. During my boat's diesel engine 600A start, pulling battery voltage supply to the board to very low, the UPS powers the RPi and its loads with no interruption or reset or Pi low voltage warnings. This upgrade to deliver a max output current of 3A, just like the official RPi AC wall plug power supply, has made all the difference. FYI, I supplied both the old and this new board from a 12VDC to 5VDC Dual-Port USB Car Charger Adapter, 4.8 Amp, 24W, using a Dual USB Male Jack Y Splitter Data Charger Cord to supply the two 2.4A channels in parallel as 4.8A to this UPS circuit. That is, supplying 5 x 4.8 = 24W to the board enables it to deliver 5.1V x 3A = 15.3W output power to the RPi. With the old V1 board output under load was 4.8-4.9VDC. With the new board it is 5.2V+. Perfect!

I was really excited about this power module, but it has two flaws, one major, one not as big of a deal but still an oversight. First the big one: It does not have any low voltage protection for the Lithium battery. If you leave your Pi running, it will eventually brown out, however the circuit does not shut down to protect the battery. You can see the LEDs pulsing as it is trying to stay alive, far below a voltage it can operate at. The major problem with this is, it will absolutely kill the Lithium battery if you allow it to do this more than a couple times, as they cannot handle a deep discharge. I measured the cell after it had been left on overnight, and it was at 2.78v. The second problem is when you have it powering your Pi and also plugged in to USB to charge (which it will if you supply it 2.5A source), when you unplug the charging source, it briefly interrupts power to the Pi causing a reset. I feel like this could be easily solved by the circuit designer. If you're just looking for a battery backpack for your Pi to run for several hours, this will totally do the job, but dont plan on leaving it sitting around on battery, as it will eventually kill its' own battery from deep discharge.EDIT: The manufacturer contacted me and let me know they revised the board to fix these two issues, and they sent me a new one. It now doesn't drop out when unplugging or plugging in. Also it does properly shut down the circuit when the li-po gets down to 3.2v.

I used this to run a raspberry pi 4b for a mobile project I was working on and it's a good battery, but it can die fast

I've been working on a project that involves adding a UPS and Raspberry Pi 5 to an enclosure, so I've been doing some detailed testing of this UPS.Unfortunately I think I'm going to have to return it, as it struggles to stay charged with power attached and an idling Pi 5. If I use the Pi to do anything that increases current draw (e.g. running a music visualizer) it'll actually run down and turn off the Pi -- even with the power supply attached.But this still might be a good UPS for you!The good:- It's a great size, and very slim even with the battery attached- Two outputs- Much cheaper than alternatives- The UART interface gives detailed information (battery level and whether power is attached)The bad:- Can't sustain a load above ~1 amp, even when connected to USB power- Wastes quite a bit of power during normal plugged-in operation- Flashing LED on the back during normal operation- You have to solder the header for the UART interfaceIf you're looking for a UPS for a load that's consistently < 1 amp, this could be a great choice! Just be aware that a higher load will run down the battery and eventually turn off your device.I played around with a number of power supplies, cables, and power monitors. No matter what I swapped out I could never get it to pull more than 1.8a from the input. This number was quite constant.Connected to a load averaging 1a (mostly-idle RPi 5 with a few things attached) the reported charge drifts up and down (as gauged by both the LEDs on the back and the report via UART), and sometimes even drifts so low that it turns off the power output. It never seems to power the pi from USB power exclusively; it always has the battery in the loop. This constant charging and discharging seems to be wasting about 0.8 amps (4 watts) of power.I would love to figure out how to get it to pull the 2.5-3a mentioned in the product description, and forward this power while charging the battery instead of dissipating so much of it.

I needed UPS for a pi project I was using as a medical device. Most monitoring devices have a battery so I need one that was reliable.This has been rock solid for over a year and the scripts to help shutdown when battery is too low work great to help keep my SD card from corrupting.Battery life for a pi 4 with no screen attached and constant wifi is around ~4hrs with the 4000 mah battery. If I attached a 7" LCD it custs the time down to less than 1hr. So if you want it to last a long time do not power a screen off the battery or get a larger capacity battery.I made a custom enclosure to house the entire projects and it works great.Will definitely get more when I need them