We have developed a robust, powerful and feature rich battery power supply board designed to fit underneath your Raspberry Pi (e.g. Zero, Model 3, Model 4), which leaves the 40pin header on top of your Pi free for all the HATs and other connections that you may need for your projects.
As well as enabling your Pi projects to become portable, it provides software access to the battery voltage and current, as well as the ON button state, so you can safely shut down the device when needed. The ON button also provides the RUN/RESET function just in case your software really gets stuck - who says that doesn't happen?
The circuit design ensures that the battery is not under load whilst being charged, allowing the charging cycle to complete accurately, whilst the board only consumes 10uA when off (compared to some designs with CPU's that consume many mA's monitoring the ON button!), ensuring maximum battery life. But at the same time, our extreme testing shows a super steady 5.1v output when delivering over 4 Amps, with 1 board driving a Pi4, display, USB hub with keyboard, mouse, webcam, and at the same time charging the battery of another board under a Pi3, also with a display and both running a heavy graphics test case.
Designed for easy integration with all your projects, we are in the pre-launch phase for our Kickstarter campaign, launching soon. If you would like more information and register to be notified when the campaign goes live, please check out https://www.theredreactor.com for details, including pictures and a video of the extreme testing. We'd love to get your support to achieve our goal so we can make this board available to everyone! Of course, feel free to ask questions too. Thank you!
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Re: The Red Reactor Battery Power Supply
Hey, that sounds like a great project, a few question, i live in the middle of nowhere and the electric is not always reliable. I use Octopi coupled with a raspberry pi, with a screen and a camera. i tried multiple power board but none are able to handle powering all this equipment and make switching from wall power to battery without creating issues. Would your board be able to handle keeping the pi up and running even during a blackout? Also how does it handle disconnection from the power grid? thanks
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Re: The Red Reactor Battery Power Supply
We experienced the same problems with existing designs when under high load, hence our design is not only designed for much higher power, but has additional output capacitance to ensure a really smooth output voltage when switching.
In the extreme video test case, see https://www.youtube.com/watch?v=DS3TtVOnquk ,you can see the Red Reactor battery supply switching from external power to run off it's internal batteries, and everything just keeps going despite the very heavy load.
When external power is back, it switches cleanly back to that and starts charging the batteries.
The manual in github at https://github.com/Scally-H/RedReactor contains the instructions for modifying the /boot/config.txt and /boot/cmdline.txt files of your Octoprint installation to support the Red Reactor.
So it should power your setup with a display and webcam without problem, but also, because the Pi can read the battery status it will know when external power is gone, and when it is restored, hence you could have a script to monitor this and view this remotely, or have it notify you.
The Red Reactor will keep the Pi running, but if power is not restored and your batteries run low you can then execute a clean shutdown to avoid losing any data.
In the extreme video test case, see https://www.youtube.com/watch?v=DS3TtVOnquk ,you can see the Red Reactor battery supply switching from external power to run off it's internal batteries, and everything just keeps going despite the very heavy load.
When external power is back, it switches cleanly back to that and starts charging the batteries.
The manual in github at https://github.com/Scally-H/RedReactor contains the instructions for modifying the /boot/config.txt and /boot/cmdline.txt files of your Octoprint installation to support the Red Reactor.
So it should power your setup with a display and webcam without problem, but also, because the Pi can read the battery status it will know when external power is gone, and when it is restored, hence you could have a script to monitor this and view this remotely, or have it notify you.
The Red Reactor will keep the Pi running, but if power is not restored and your batteries run low you can then execute a clean shutdown to avoid losing any data.
Re: The Red Reactor Battery Power Supply
Sounds like what a lot of people have been looking for....
....now it just comes down to price.

....now it just comes down to price.

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Re: The Red Reactor Battery Power Supply
Thank you! Of course we hope you'll find the features good value, and we'd love your support to make it happen.
If you register your interest at our home page we can notify you when we launch the campaign and hopefully you can take advantage of the early bird discount as well.
If you register your interest at our home page we can notify you when we launch the campaign and hopefully you can take advantage of the early bird discount as well.
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Re: The Red Reactor Battery Power Supply
We have just completed some long-term testing of the Red Reactor.
When we used other battery power supply boards we found that there was a significant voltage drop even whilst the whole system was OFF, and realised that this was due to the current drawn by their on-board controllers. In one case this caused the voltage to drop by 0.2v (from 4.131 to 3.928) in just 6 days. So by that rate it would be dead in a month, and cause a reduction in battery life by going through many more charge cycles.
So we paid special attention to this aspect in our design, and in our long-term testing measured a voltage drop of only 0.03v over 6 weeks! (4.184 on 7/5/21, down to 4.155 on 15/6/21).
When you look at the self-discharge rate of lithium batteries, at approximately 2% per month, that represents most of the losses we measured on our board. So not only will it take over 9 months to drop by the same 0.2v on the Red Reactor, there would be far fewer charge cycles as well.
We settled on the 18650 type batteries because they have excellent performance and are much cheaper than the flat (Molex) connector based batteries used in some designs - for example, another brand charges £25 for their 5000mAh battery, whereas the 18650's can be found for around £5 each, thus reducing running costs and battery waste.
Thank you for registering your interest at https://www.theredreactor.com , it really helps us in setting our goals.
When we used other battery power supply boards we found that there was a significant voltage drop even whilst the whole system was OFF, and realised that this was due to the current drawn by their on-board controllers. In one case this caused the voltage to drop by 0.2v (from 4.131 to 3.928) in just 6 days. So by that rate it would be dead in a month, and cause a reduction in battery life by going through many more charge cycles.
So we paid special attention to this aspect in our design, and in our long-term testing measured a voltage drop of only 0.03v over 6 weeks! (4.184 on 7/5/21, down to 4.155 on 15/6/21).
When you look at the self-discharge rate of lithium batteries, at approximately 2% per month, that represents most of the losses we measured on our board. So not only will it take over 9 months to drop by the same 0.2v on the Red Reactor, there would be far fewer charge cycles as well.
We settled on the 18650 type batteries because they have excellent performance and are much cheaper than the flat (Molex) connector based batteries used in some designs - for example, another brand charges £25 for their 5000mAh battery, whereas the 18650's can be found for around £5 each, thus reducing running costs and battery waste.
Thank you for registering your interest at https://www.theredreactor.com , it really helps us in setting our goals.
Re: The Red Reactor Battery Power Supply
How can I read the ON button state in my software? On my current UPS it is a tiny built-in button and I do not have a way to know if it is being pressed, and how long for.
Re: The Red Reactor Battery Power Supply
Nice project. Just checked your video.I know this is an extreme case but, at around 1:49, just before the DC supply is switched off, there's the undervoltage warning bolt on the Pi4 screen (and the red LED on the board turns off). The same happens when switching the DC supply back on. Maybe a video with a more average usage showing the Red Reactor's capabilities might help to understand what it can give in normal circumstances.TheRedReactor wrote: ↑Sun Jun 13, 2021 4:47 pm
In the extreme video test case, see https://www.youtube.com/watch?v=DS3TtVOnquk ,you can see the Red Reactor battery supply switching from external power to run off it's internal batteries, and everything just keeps going despite the very heavy load.
When external power is back, it switches cleanly back to that and starts charging the batteries.
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Re: The Red Reactor Battery Power Supply
Thank you for the feedback. Indeed the goal is to show that even with one board supplying over 4.5 amps to both the Pi4 and the Pi3, both systems were able to continue running. But as you mention, the DC bench supply was struggling to deliver the current as it is only rated at 5 Amps, and you can see its display flickering before we switch to the battery and the lightning symbol disappears.
The board has quite a lot of on-board voltage smoothing capacitance but also additional mounting holes to support more in case of more extreme requirements.
The introduction video at https://www.youtube.com/watch?v=lbSTJwIG9jo shows some of the more 'normal' use cases where we have used it with a Pi Zero, Pi Model 3 and a Pi4, for example in our radio design, and a Pi4 driving a display and a USB hub connected to a keyboard, mouse and webcam. As per the beginning of the extreme test case video, the Pi4 boots and runs a maximum load without any under voltage issues.
The board has quite a lot of on-board voltage smoothing capacitance but also additional mounting holes to support more in case of more extreme requirements.
The introduction video at https://www.youtube.com/watch?v=lbSTJwIG9jo shows some of the more 'normal' use cases where we have used it with a Pi Zero, Pi Model 3 and a Pi4, for example in our radio design, and a Pi4 driving a display and a USB hub connected to a keyboard, mouse and webcam. As per the beginning of the extreme test case video, the Pi4 boots and runs a maximum load without any under voltage issues.
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Re: The Red Reactor Battery Power Supply
It is indeed awkward if the power supply uses such a tiny built-in button because typically it is in the wrong place when you come to build your project case, or it just doesn't go with the overall design.
But it is worse if you can't read the button state because then you need another button just for things like getting your software to go into stand-by, or use a longer press if you want your software to execute a software controlled shutdown.
The Red Reactor has a simple button interface, so you can choose a momentary switch and cable lengths to fit with your project. As well as turning everything ON, you can then read the state of this button via the provided GPIO port. With the example python code on our GitHub page it shows you how to set an interrupt to trigger a timer with which you can measure the length of the button press, for example, short, medium and long. If you hold it for 10 seconds though it will also pull the RUN signal low, in case you want to wire that to your Pi and use it to force a reset.
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Re: The Red Reactor Battery Power Supply
As part of our FAQ we answered a question about using the Red Reactor with a real time clock so you can completely shut down the Raspberry Pi system and then use a timed alarm to power everything back up again.
Not all projects need this feature of course, but if you're building something that only needs to wake up say once an hour, or once per day, then by shutting down completely, and with the fact that the Red Reactor only consumes a few micro-amps when OFF, you could potentially get many months of battery life for your monitoring applications.
Because our board provides easy access to the button interface, we decided to make a short video to show you how to make that work, which you can see at https://youtu.be/NvDd5q-TUnc
It is worth mentioning that if you don't power the system OFF before an alarm, your software will receive the alarm interrupt in the same way as our example button interface software shows. So you can use the same setup for projects that stay active and need a timed action interrupt, for example to shut everything down after midnight. The second alarm register of the DS3132 device could wake it all up again too!
We hope you'll find the video interesting!
Not all projects need this feature of course, but if you're building something that only needs to wake up say once an hour, or once per day, then by shutting down completely, and with the fact that the Red Reactor only consumes a few micro-amps when OFF, you could potentially get many months of battery life for your monitoring applications.
Because our board provides easy access to the button interface, we decided to make a short video to show you how to make that work, which you can see at https://youtu.be/NvDd5q-TUnc
It is worth mentioning that if you don't power the system OFF before an alarm, your software will receive the alarm interrupt in the same way as our example button interface software shows. So you can use the same setup for projects that stay active and need a timed action interrupt, for example to shut everything down after midnight. The second alarm register of the DS3132 device could wake it all up again too!
We hope you'll find the video interesting!
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Re: The Red Reactor Battery Power Supply
There are some use cases where you don't have easy access or system up-time is critical, yet consume too much power to run for long periods on batteries. So whilst a high performance battery back-up power supply is essential to ensure an orderly shutdown when there is an external power outage, you also want to restart everything as soon as the external power is restored.
Whilst the Red Reactor can easily support a Pi4 with accessories and cleanly switch to battery power, you can also use the Vin port and ON button interface to easily integrate additional functionality into your project. In a previous video on our channel we showed how to add an RTC alarm to manage timed power-on and power-off requirements.
We've now created a new short video at https://youtu.be/Ob2czPwil8o on how to add a simple circuit to detect when external power is restored, which connects to the Vin port and operates alongside an ON button to create a trigger (even if you're using USB as the power input). A simple script (here running on the Pi4 with display, USB hub, mouse and keyboard) will detect a power outage over I2C and perform a safe shutdown, whilst the system is automatically rebooted when external power returns!
Whilst the Red Reactor can easily support a Pi4 with accessories and cleanly switch to battery power, you can also use the Vin port and ON button interface to easily integrate additional functionality into your project. In a previous video on our channel we showed how to add an RTC alarm to manage timed power-on and power-off requirements.
We've now created a new short video at https://youtu.be/Ob2czPwil8o on how to add a simple circuit to detect when external power is restored, which connects to the Vin port and operates alongside an ON button to create a trigger (even if you're using USB as the power input). A simple script (here running on the Pi4 with display, USB hub, mouse and keyboard) will detect a power outage over I2C and perform a safe shutdown, whilst the system is automatically rebooted when external power returns!
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Re: The Red Reactor Battery Power Supply
Just wanted to give you a quick update on our progress. We were expecting our Kickstarter campaign https://www.kickstarter.com/projects/pa ... ly-matters to go live this week but unfortunately the world's shortage of ICs (as you've no doubt read about in the news) has affected one of the components on our board. We obviously don't want to present a delivery schedule that we cannot commit to, so we'll look at alternative suppliers and solutions first.
We'd be happy to hear if you know of suppliers' stock for this particular component (INA219AIDCNR/INA219BIDCNR) or had good results with comparable, alternative parts. We'll let you know how we get on!
We'd be happy to hear if you know of suppliers' stock for this particular component (INA219AIDCNR/INA219BIDCNR) or had good results with comparable, alternative parts. We'll let you know how we get on!
Re: The Red Reactor Battery Power Supply
Chip 1 ExchangeTheRedReactor wrote: ↑Fri Aug 06, 2021 9:39 amJust wanted to give you a quick update on our progress. We were expecting our Kickstarter campaign https://www.kickstarter.com/projects/pa ... ly-matters to go live this week but unfortunately the world's shortage of ICs (as you've no doubt read about in the news) has affected one of the components on our board. We obviously don't want to present a delivery schedule that we cannot commit to, so we'll look at alternative suppliers and solutions first.
We'd be happy to hear if you know of suppliers' stock for this particular component (INA219AIDCNR/INA219BIDCNR) or had good results with comparable, alternative parts. We'll let you know how we get on!
https://www.chip1.com/search?partno=INA219AIDCNR
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Re: The Red Reactor Battery Power Supply
Thank you for that, but despite registering there we did not get any response. We have located another supplier but are currently checking that they will be reliable. Hopefully we can launch soon!
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Re: The Red Reactor Battery Power Supply
These days, everything is controlled by software. In fact, even my DVD player's ON/OFF button is no longer hard wired into the power supply, and needs its software to decide that I really wanted to turn the thing off. Well, many a time that software gets completely stuck, refuses to obey my command, and the only option is to pull the power plug at the back. Not a pretty sight with all the dust and cobwebs, I can tell you!
Now imagine this happening with your Raspberry Pi project, but when the mains is backed up by battery power you can no longer just 'pull the plug'. And when your Pi is inside a nice case design, getting those batteries out is not going to be a quick and easy task.
That is why the Red Reactor has a nifty Hard Reset function built into the ON button interface, so all you have to do is wire the RUN port of the Red Reactor to the RUN port on your Pi. So now, a long press of that ON button sorts it all out for you, and no need to pull the plug on that pesky software!
This short video ( https://youtu.be/_gN_dDZBG0A ) shows you how the ON button and RESET functions are integrated together for all your projects, and I hope you'll find it useful! Please continue to register your interest at https://www.theredreactor.com , thank you!
Now imagine this happening with your Raspberry Pi project, but when the mains is backed up by battery power you can no longer just 'pull the plug'. And when your Pi is inside a nice case design, getting those batteries out is not going to be a quick and easy task.
That is why the Red Reactor has a nifty Hard Reset function built into the ON button interface, so all you have to do is wire the RUN port of the Red Reactor to the RUN port on your Pi. So now, a long press of that ON button sorts it all out for you, and no need to pull the plug on that pesky software!
This short video ( https://youtu.be/_gN_dDZBG0A ) shows you how the ON button and RESET functions are integrated together for all your projects, and I hope you'll find it useful! Please continue to register your interest at https://www.theredreactor.com , thank you!
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Re: The Red Reactor Battery Power Supply
We’re pleased to announce the first release of our Red Reactor Battery Widget for the Raspberry Pi OS, so you can see the battery status right from your desktop screen! Perfect for when you use the Red Reactor to make your Pi project portable, or you just want to make sure all is well in case you loose mains power.

The battery icon will show you the percentage charge, and during charging and discharging you can also see the battery current and voltage in the tool-tip when you hover over the icon, as well as the estimated time to full charge or how long you can keep going till you run out of juice!
The code is designed for use with the Red Reactor battery power supply, and is available from our Github repository. For more information about the battery charging and discharge profiling results head over to our blog at https://www.theredreactor.com/2022/01/2 ... ry-widget/
Feel free to post comments here or on our website blog, we'd love to hear from you!

The battery icon will show you the percentage charge, and during charging and discharging you can also see the battery current and voltage in the tool-tip when you hover over the icon, as well as the estimated time to full charge or how long you can keep going till you run out of juice!
The code is designed for use with the Red Reactor battery power supply, and is available from our Github repository. For more information about the battery charging and discharge profiling results head over to our blog at https://www.theredreactor.com/2022/01/2 ... ry-widget/
Feel free to post comments here or on our website blog, we'd love to hear from you!
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Re: The Red Reactor Battery Power Supply
Thank you for continuing to track our progress (and for reading this far down this thread!). The world chip supply shortage is still causing a problem for us, but we are hopeful that we can launch soon as things are slowly improving.
In the meantime, we have developed a Flask based web application that will enable you to monitor your battery status and usage remotely via a web browser, configure the monitoring process and even perform a remote reboot or shutdown. Perfect for when your Pi is used remotely or running without a display!

For more details please head over to our update on https://www.theredreactor.com/2022/04/0 ... onitoring/, and you can download the code with install instructions from our Github page at https://github.com/Scally-H/RedReactor.
*** UPDATE *** We added the output from vcgencmd into the status report, so you can see if/when the CPU/GPU is affected by temperature throttling etc. A handy tool tip explains the result values when you hover over the value. We hope it gives you enough example code to extend it for your own projects with the Red Reactor!
In the meantime, we have developed a Flask based web application that will enable you to monitor your battery status and usage remotely via a web browser, configure the monitoring process and even perform a remote reboot or shutdown. Perfect for when your Pi is used remotely or running without a display!

For more details please head over to our update on https://www.theredreactor.com/2022/04/0 ... onitoring/, and you can download the code with install instructions from our Github page at https://github.com/Scally-H/RedReactor.
*** UPDATE *** We added the output from vcgencmd into the status report, so you can see if/when the CPU/GPU is affected by temperature throttling etc. A handy tool tip explains the result values when you hover over the value. We hope it gives you enough example code to extend it for your own projects with the Red Reactor!
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Re: The Red Reactor Battery Power Supply
Just a quick update to tell you about our Power of Standby experiment, which we documented on https://www.theredreactor.com/2022/03/0 ... f-standby/
We had a Raspberry Pi Zero powered by the Red Reactor using 2x 3000mAh batteries, set up with an RTC alarm to boot up every 4 hours to take a moisture sensor reading, email it out and turn itself completely off again. With these measurements we could show the benefit of the Red Reactor's ultra-low standby current (few uA) for sensor applications, and our setup was able to take 481 separate readings (it took 6 readings per day) before finally signing off from duty today.
So, if you just needed 1 reading per day, we've shown that it could run for well over 1 year on batteries. It’s funny, I kinda got to like seeing emails from my Pi every day…
We had a Raspberry Pi Zero powered by the Red Reactor using 2x 3000mAh batteries, set up with an RTC alarm to boot up every 4 hours to take a moisture sensor reading, email it out and turn itself completely off again. With these measurements we could show the benefit of the Red Reactor's ultra-low standby current (few uA) for sensor applications, and our setup was able to take 481 separate readings (it took 6 readings per day) before finally signing off from duty today.
So, if you just needed 1 reading per day, we've shown that it could run for well over 1 year on batteries. It’s funny, I kinda got to like seeing emails from my Pi every day…
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Re: The Red Reactor Battery Power Supply
We're pleased to announce our collaboration with Fogstar Ltd (https://www.fogstar.co.uk/), the number 1 battery supplier in the UK and Europe who provide genuine, tested batteries at extremely competitive prices. As part of our Kickstarter campaign we will be able to offer a special discount voucher for use with any batteries purchased from Fogstar Ltd, giving you a substantial and very worthwhile saving on adding a complete, robust battery power supply system to all your projects!
Whether your project needs large capacity batteries for extended portable use, high power delivery for a server or accessories, or simply reliable performance for remote applications, you can choose the best, genuine battery from a wide range of brands including Samsung, Sony/Murata, LG, Molicel, BAK and more.
And if you register with us now at https://www.theredreactor.com/contact/, we'll be very happy to send you an amazing 20% discount voucher to use at Fogstar in the meantime.
For more news and information as we continue to get closer to launch, please visit us at https://www.theredreactor.com/news/
Whether your project needs large capacity batteries for extended portable use, high power delivery for a server or accessories, or simply reliable performance for remote applications, you can choose the best, genuine battery from a wide range of brands including Samsung, Sony/Murata, LG, Molicel, BAK and more.
And if you register with us now at https://www.theredreactor.com/contact/, we'll be very happy to send you an amazing 20% discount voucher to use at Fogstar in the meantime.
For more news and information as we continue to get closer to launch, please visit us at https://www.theredreactor.com/news/
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Re: The Red Reactor Battery Power Supply
We're very pleased to have been accepted into PCBWAY's Crowdfunding Project Sponsorship Programme, and with their excellent support this has enabled us to proceed with our final prototypes and set our target Kickstarter campaign launch date for September! We're waiting for our new boards to arrive and all being well with testing we hope to have everything ready for launch!
You can find more details on this in our latest update at https://www.theredreactor.com/2022/07/0 ... aunchdate/ - we know it's been a long wait but thank you all for your continued support!
You can find more details on this in our latest update at https://www.theredreactor.com/2022/07/0 ... aunchdate/ - we know it's been a long wait but thank you all for your continued support!
Re: The Red Reactor Battery Power Supply
what a coincidence that's gonna be very helpful for a lot of people like me i was looking about it for a long time and here we go i found it.