Over the last decade or so, battery technology has improved massively. While those lithium cells have enabled thin, powerful smartphones and quadcopters, [patrick] thought it would be a good idea to do something a little simpler. He built a USB power bank with an 18650 cell. While it would be easier to simply buy a USB power bank, that’s not really the point, is it?
This project is the follow-up to one of [patrick]’s earlier projects, a battery backup for the Raspberry Pi. This earlier project used an 14500 cell and an MSP430 microcontroller to shut the Pi down gracefully when the battery was nearing depletion.
While the original project worked well with the low power consumption Pi Model A and Pi Zero, it struggled with UPS duties on the higher power Pi 3. [patrick] upgraded the cell and changed the electronics to provide enough current to keep a high-power Pi on even at 100% CPU load.
The end result is a USB power bank that’s able to keep a Raspberry Pi alive for a few hours and stays relatively cool.
Care to sell these?
Yes, that’s the plan! Trying to get these in production ASAP for people who want to have a reliable UPS for the Pi 3, but I’m also making sure I do enough testing so I will be putting out a good product. You should be able to buy them on Tindie before the end of the year. :)
How about a version that can take power over ethernet.
How did testing go? Do you have a production model? I have a non-Pi project that this would work for.
You’d seriously pay for this? Its like $3 of electronics… If toy already have a Pi, you probably are at least somewhat into hobbyist electronics… Buy an 18650 cell holder for a buck off eBay, buy a 4.2v – 5v 1A or 2A USB charging board(not something that’d need some odd micro USB to micro USB cord like the one pictured would need). There ya go. You’ve completed this project(which is seriously nothing new, just talked up like its new to trick people exactly like yourself into thinking they’re buying something they couldn’t get before) and saved tons of money!
If you want to get more technical, add more batteries, add an actual buck/ boost circuit on some protoboard with a micro USB port to keep it topped up, add a small .36″ LED voltmeter to keep track of cell voltage, add an ammeter to keep track of current, etc. You could probably do all of that for still less than you’ll buy this simple replicant of hundreds of other peoples projects.
Thanks for dissing my hard work. *lol* I must be a complete idiot for having to have spent 2 years to perfect this to the point where it is now. I suggest you try what you write here and see how well it replicates the functionality I provide. For everyone else, I suggest you save yourself a lot of trouble. :)
I’m glad most people are not like you and are willing to support a small maker. Obviously in the small volumes I do right now I can’t compete with China.
Well anyone into electronics would have noticed you can put jumper pins on the board and not need a micro usb to micro usb cable. The micro usb is for charging. Just saying.
Also yea, if pay a few bucks for a device such as this in a clean form factor. It’s not the price I would be buying, it’s the product.
An underrated project. Could not recommend more – Raspberry Pi computers do need portability add-ons to make actually useful portable Pi projects, and currently there aren’t too much of the good ones. I hope to change that as well =)
There’s a difference between portability and portable power though. With a case it fits in your pocket. And it has sockets so u can plug a keyboard and monitor wherever u are. The os can run off an sd so u don’t need to carry around a portable HD even. It’s basically THE portable computing unit atm.
The portable power is basically the problem off the century (remember the Samsung horror few weeks ago with exploding batteries). This is
Well THE portable computing unit would probably be the newest Intel NUC. It’s got an i7 (although I’m not quite sure what you need an i7 for where you couldn’t get a laptop instead )
If you do not need an I7, the ARCHOS PC Stick, is much cheaper, you plug it into the screen, it does have wifi and run Windows10 like a pro
It is not just a LiPo 18650 – it is a LiFePo4!
That means it is inherently safer, has an even lower self discharge and more load cycles.
But near half of the volumetric energy density…
Yes, but much less explodey
I’m not usually shooting at my batteries or using them as a hammer, so Li-ion having double the working time is just perfectly safe for me. ;)
Li-Ion battery short circuit,overcharge,undervoltage EXPERIMENT
https://www.youtube.com/watch?v=bNNWbm681AI
Volumetric density of LiPos is overrated. Due to their short cycle life, they will have less capacity than LiFePO4 after a couple 100 or so cycles. Then after 500 or so they will be dead, while the LiFePO4 will keep chugging along for another 2000+ cycles.
these are nice and all but i have been powering my pis off of a 2 series cell pack and battery life is around 2 hours tops. of course im not getting full discharge since the smps drops out if i go below a certain voltage. i plan to go up to a 3 series pack. this will give me full discharge and an additional cell to boot. il have to throw on a safety board to keep from over discharging though.
Part of the reason for this project is to make sure the Pi is always gracefully shut down when power fails. Very necessary for projects that can’t risk corrupted SD cards.
i guess thats a nice feature for things like servers. i for one am still looking for a portable solution that has some staying power. none of the go to off the shelf solutions seem to cut it.
So wire in 5 more 18650 batteries in parallel and you have more capacity. That’s how all the USB battery packs do it.
Has anyone seen a project that uses 10+ 18650’s to power a Pi and a few add-on bits and pieces for (say for instance) 24 hours……I have purchased 20-18650’s and a VRUZEND.com battery caps kit (with a charger and balancer). In hopes of being able to acheive, 24 hrs, stand-alone, atonomous runtime with my RPi Project, that I have been working on for the last 2 years now….I left a message in the VRUZEND.com fourm 5 days ago and it is still “awaiting moderation”…Maybe they just dont like answereing questions of this type…..
I look forward to hearing your suggestions and ideas….thank you for your time reading this….
Alan
Good to see more projects like these, since they’re certainly useful. I’m surprised more folks haven’t tackled putting together something to take up the mantel of those PiUPS guys since their project went south. They promised us version 2, then went out of business…
This would pair nicely with the Stratux (Pi-based ADS-B/GPS receiver for light aircraft).
I like this approach lot, but I have 2 questions:
1. Is it open source? I did not find any sch/pcb files.
2. How much steady current can it provide?
Thanks!
I really like the circuit board!