Raspberry Pi Battery Power

Running a Raspberry Pi on batteries -- specifically a 12V lead acid battery and a USB power bank. Video includes expected battery life calculations and battery life tests and for a Raspberry Pi 4, Raspberry Pi Zero, and other Pi models.
The Raspberry Pi Foundation power consumption page is here:
www.raspberrypi.org/documenta...
If you enjoy this video, you may be interested in my recent Raspberry Pi project videos:
Raspberry Pi Weather Station:
• Raspberry Pi Weather S...
Raspberry Pi Anemometer:
• Raspberry Pi Anemomete...
More videos on SBCs, computing and related topics can be found at:
/ explainingcomputers
You may also like my ExplainingTheFuture channel at: / explainingthefuture
Chapters:
00:00 Introduction
00:52 Five Pis
02:41 USB power bank
05:34 Power bank tests
12:34 Lead Acid battery
19:37 Wrap
#RaspberryPi #Batteries #BatteryPower #ExplainingComputers

[@qc15pvetter]

These videos are like what Saturday morning cartoons use to be to me when I was a kid.

[@dougcox835]

Except very few children would watch this on a Saturday morning. I will say though that when I was a kid on saturday mornings there were times when the cartoons were not interesting and I would switch over to the PBS station where they would play educational videos for the local community college. I learned a lot from watching those boring college course supplemental videos.

[@nosuchthing8]

Yes!

[@tedoyle61]

I look forward to each one he creates.

[@Whipster-Old]

I wish I'd been watching Professor Barnatt when I was a kid. Hell yeah.

[@Matrxmonky]

Yup, woke up at 10, got some clothes on and the PC warmed, had the lovely better half brew a coffee, and we begin our Sunday with the dulcet tones of Mr. Barnatt.

[@RaviRJoshi]

Videos like this is what makes world a better place, and EC a popular channel. Prof.

[@ExplainingComputers]

Thanks. :)

[@RyanGonTV]

Agreed

[@PhG1961]

Indeed !

[@kev7345]

Rumour has it that Chris is running a P Zero off a car battery .. he hopes to show us the results on his 85th birthday...

[@TwoTonTaft]

So, like a month or two? (this guy's got jokes for days)

[@QWERTASDFG303]

Umm, everyone knows Chris is a vampire. Make that his 385th birthday.

[@michealkinney6205]

Lol, how about running it off a 159lb 12v 255ah AGM Lead Acid Solar Battery (that a ridiculous 3.06kWh's of capacity). In retrospect, that's 36 times more than the Lead Acid battery tested (12V @ 7Ah = 84 wH). That power a RPi for nearly a year, in theory (Lead Acid tested lasted 187 hours x 36 = 6732 / 24 hours == 280.5 Days). There's a "fun" or boring video for you, depending on how you look at it. Just some food for thought!

[@acromatfpv894]

"Inconceivable!" 😄

[@grimuk3817]

Rumor has it Chris is running a car off a P Zero ...

[@aryantiwari1945]

This video was incredible. This must have taken a lot of effort! Lead acid FTW!

[@An.Individual]

re table at 5:15 A power bank is rated at it's nominal voltage which is 3.7V for lithiums cells. So the energy in a 10,000mAh battery is 37 watt hours (10A * 3.7V) The current consumed by the Pi is rated at 5V. runtime for Pi4 is (3.7 * 10 * 75%) / (5 * 0.6) = 9.25 hours

[@michealkinney6205]

I agree, but nominal power of a Lithium battery is actually 3.6 volts. Lithium Power Bank: (3.6 * 10 * 0.75) / (5 * 0.6) = 9 hours Lead Acid Battery: (12 * 7 *.75) / (5 * 0.6) = 21 hours (2.33 times more energy) But I also expect a slightly higher efficiency for the Lead Acid batteries "capacity" over the Lithium battery bank as the differential between maximum and minimum voltages is greater, and there is a step down converter in the power bank, so the efficiency loss also needs to be considered. This accounts for the Lead Acid battery getting nearly 3X the time.

[@techntell6684]

As this experiment went on, you could hear his enthusiasm diminishing with each run 😄 It probably felt like the universe would come to an end before production was finished! Kudos and great video!

[@bananus815]

We shouldnt forget Mr.Scissors. He helps to get all reviews

[@ExplainingComputers]

True.

[@ddegn]

Mr. Scissors' witty humor is the main reason I watch this channel.

[@bananus815]

@@ddegn noice

[@Uniblab8]

...forgot to mention...my Sunday mornings are not complete unless I view and digest your videos. Well done.

[@xjet]

Perhaps the lead-acid results were skewed because without an intelligent voltage cut-off, the lead-acid battery would exhaust its entire capacity, well below the safe minimum. The power-bank is smart enough to disconnect the load when the battery is down to the safe minimum voltage but that simple buck converter will likely keep going down to almost 5V of input voltage.

[@CampGareth]

There isn't much energy in a lithium ion battery below safe cutoff voltage, something like 5% of the rated capacity if I remember my curves. But yes, the lead acid depth of discharge here is far too much for that battery to have a long life.

[@Avocettech]

Yes - a nice add on feature for lead-acid applications would be some sort of RPi power down and then complete power switch off when the battery approaches 12.3 Volts.

[@RealJonDoe]

@@Avocettech a voltage divider on an analog input should be able to accomplish this.

[@arthurhardy]

That is exactly what happens, And every time you run the lead acid down that far you reduced the capacity and skewed the numbers for subsequent tests

[@nid274]

@Abstractism I learned that lead acid battries should not discharged below 10 to 9.5v in the worst case.

[@msulemanf]

Love it, solar next? Easily one of my top 10 channels - consistently delivering well produced, interesting, accurate, exhaustive & kind-spirited videos. Thank-you.

[@RaviRJoshi]

Yep. I used to run Rpi 4 on a mobile battery. I guess I'll power that battery from solar, soon.

[@AdrieKooijman]

Solar? Running a RPI until the sun runs out? 😜

[@AdrieKooijman]

@@flethacker at night time the sun is hidden for some of us, not 'out'

[@jacobcastro1885]

Solar is perfect for charging and maintaining these batteries. The best channel on KZbin is DIY SOLAR POWER with Will Prowse.

[@dang48]

@@RaviRJoshi I did some research a couple of years ago and if I remember correctly, a 9W panel could power a pi. (That would be the model 3B).

[@BryanBenoit]

I absolutely love every single video on this channel. Thanks a million !

[@xjet]

It is also worth nothing that the mAH capacity of many power-banks is not what you might think. Many of them use the mAH capacity of the battery in the bank and since that capacity is at a lower voltage (nominal 3.7V) then you do not get anywhere near that at the 5V the power bank sends out the USB port. To deliver 1A at 5V the battery will see a drain of (@4V)) 1.2A. This means that a 10,000 mAH power bank has a deliverable capacity of significantly less than the 10,000mAH at which the battery is rated. Then there are the efficiency losses of the boost converter that steps the voltage up from a nominal 3.7V to 5V.

[@michealkinney6205]

Exactly what I was thinking. So the actual number of the power bank would be 3.6V nominal (though advertised as 3.7V which is misinformation, which someone smarter than me pointed out years ago) x 10Ah = 36 Watts / 5V = 7,200 mAh. That and, I expect a slightly higher efficiency for the Lead Acid batteries "capacity" (84 wH / 5V is 16.8 Ah) over the Lithium battery bank as the differential between maximum and minimum voltages is greater. And then calculate the internal boost converters loss (boost conversion is slightly worse than step down efficiency) as you suggest, and bob's your uncle, the numbers are nearly spot on, lol. Anything left over can be attributed to "estimates" in efficiency and usage. I love math, especially as it applies to energy.

[@Lord_Legolas_Greenleaf]

Was the current draw of the LED accounted for? What 15mA or less? The power draw of anything is a general guideline. Components specification's are a guideline as well. Not all components are equal - some will draw more than rated, some will draw less. But this is only part of the equation. The other part is when the battery starts to drain; it's ratings get worse with the condition (remaining charge) of the battery as the condition goes down. And here again the 'components' of the battery comes into play. As for that converter - I doubt it's efficiency is 90%! I saw similar converters with a google search and they're 'unknown manufactures.' I would guess that if your lucky they're "approaching" 90%! YES! Having worked with fire alarms and security systems that all use those types of batteries they are great! And especially since these 'uses' aren't 'critical' it doesn't really matter. Since I am an Electronics/Computer Technician I would use 'dependable' & "reliable" parts from known and trusted manufacturers. And then there comes 'component' availability! If you can only get certain parts - then that's what you'll use! But @ExplainingComputers is correct! Test before you put it out into the real world.

[@ddegn]

Without knowing the voltage of those mAH, the figure it pretty much meaningless. mWH is what should be used in comparisons like this. The 75% is pretty close to what you get if you're assuming 5V from a 3.7V battery.

[@nickpelov]

@@Lord_Legolas_Greenleaf A led can be clearly visible at just 1-2 mA

[@santoshstudy5812]

Actually, what it really means is instead of specifying battery capacity in mAH, it should be specified in volts*amps*time I e. In Joules. A 10,000 mAH at 3.6v will amount to 10Amp*3.6v*3600sec = 129 K Joules of energy. Just a comparison, 1 kg of gasoline has 40M Joules of energy. So, the 10,000mAh battery above is really only worth 3 grams of gasoline. Just shows how energy dense fossil fuels are and why humans are so addicted to it. And if he runs pi-0 on a full tank worth of gasoline (like 50kg or so), it indeed may last till his 85th birthday, may even last till his son's 85th birthday.

[@FuzzyElf]

From one Christopher to another: Thank you very much for sharing your knowledge and creativity -- and humor -- in your remarkable videos.

[@duytdl]

Can always count on EC for no-nonsense to the point videos on these subjects. Well done sir!

[@mikecarlson6416]

this is absolutely pure fun to see the experiment result, thanks a lot

[@shawn8054]

Always enjoy waking up to a new video from you!

[@ritmo1130]

What a great video! Always wanted to see something like this. Thanks!!

[@gregadams558]

Always love the dry humor.

[@piconano]

When my daughter moved in her apartment, I garbed the small alarm controller the previous owner left behind. It had a battery like yours making 3/4 of the enclosure, and it was only 2 years old. It now provides power to my RPi2B+ Rpi Noir camera, running RPi-Cam-Web-Interface on Raspbian, making the best IP security camera in the world for $50 !! I connected a beefier 5V @5A buck converter than what you show in your video to power the setup 24/7. That's all I had. Fortunate for me, the internal 12V SLA charger circuitry can supply 1A to charge the battery (~12W). Running a Rpi is a walk in the park for the built-in charger. When I lose power the charger will stop, but the 12V battery is fully charged and ready to go. I never tested how long it would take for the system to run down. Now I've got a pretty good idea. Thanks to your video.

[@emilrasmussen7429]

This is by far the best video I have found on KZbin, thank you so much!

[@markdonnelly1913]

Your videos never disappoint, well done again. I nearly choked on my coffee with your reasoning for not testing all the devices though, hilarious!

[@jeyendeoso]

Excellent video, Chris, I wasn't expecting battery benchmarking hahaha Now I can't wait for the greenhouse video!

[@iwinrar5207]

I was just researching this topic. This brings it all into one easy place. Thanks!

[@drewswoods]

Really appreciate these types of videos. Learning more and more about my new computer.

[@deechvogt1589]

Awesome practical application testing Chris. I will remember the buck converter if I ever have a need for long term away from main power application for my Raspberry Pi. Thanks Chris. Cheers and as always stay well.

[@dj_paultuk7052]

Great Scott setup a SBC to water his greenhouse a few weeks back. His also manually activates via a txt message from a mobile phone.

[@roembol]

This is exactly the video I needed. I rarely like a video these days, but this one deserves it!

[@theoriginaldylangreene]

This is really interesting data, very useful. Thank you for putting in a huge amount of time and effort to collect it! Every time someone asks about battery endurance with a RPi, I will link them to here.

[@spiders-tours]

Your next project would be interesting if a solar panel (which should be usable in a greenhouse) can charge the battery whilst it's in use. The application could work for a very long time indeed. Nice tests, thanks for the video.

[@MicrobyteAlan]

Excellent I’ve been wanting to control my garden railroad with a Raspberry Pi.

[@ExplainingComputers]

Then this may help make it happen!

[@ronb6182]

I thought the train ran on AC. St least all mine do.

[@robloxianfilipinocsgcars]

I'm grateful that you did all of these test. Now I know what power source is the best for my raspberry pi project.

[@HermannKerr]

This is probably one of the most interesting videos you have put out. I am really impressed. Thanks it was very informative and liked how you programmed the test.

[@treshanremolano159]

Rushed in to watch this, learned a lot in under 10 to 20 minutes of video!

[@plica06]

This video must have taken weeks to make.. now that is dedication!

[@ExplainingComputers]

Yes, many patient weeks were involved! :)

[@BeOurBee]

This is fantastic, exactly the kind of thing I always wondered about but never found satisfactory information for on the web. Until now!

[@Coyotehello]

Your videos are always such a treat! Thank you.

[@TheTechieScientist]

Whatever happens in the world ....EC is always there to support us and get our spirits up on sundays.. 😁...thank you

[@W4RR4NTW0LF]

Really interesting figures! In relation to the PiZeroW, I regularly use one running at full load, with an e-ink display off a 12,000mAh LiPO bank and I generally get about 50-55hrs of use from it. It's neat to see your figures fitting in so well with my experience on a number of Pi systems. :)

[@corpliner1506]

Wow, I am doing the exact same thing. Odd coincidence

[@nathanisip]

Kudos to going through all the effort of testing! I was thinking of some fancy gpio interfacing to a monitor pi and had to do a face palm when you discussed writing to a spreadsheet, simple and elegant!

[@michaelgkellygreen]

Brilliant tests and presentation. I have loved looking back through your older videos. Learned so much, Thanks

[@insanemainstream3633]

Woohoo happy Sunday morning everyone!

[@nosuchthing8]

Dude, your icon...

[@frankligas2249]

Thanks for the video. Design experience idea. Back in the mid 1990's I had a project where a laptop needed to run a weather station for one month. This was out in a remote farming location. I set up the laptop to run from two 12 volt marine deep cycle boat batteries. The batteries were connected with wires soldered onto the power connection ports of an APC brand battery backup unit designed to run the computer when the power failed. So by starting with a battery backup unit, that took almost all of the engineering out of the equation. APC battery backups run on a 12 volt, lead acid battery identical to the one you show in this video. The build was simple. Buy a battery backup unit. Open it up and remove the small 12 volt battery and solder longer wires that would connect to the two bigger boat or car batteries. Then take the battery backup apart and cut the alarm buzzer off of the circuit board. When the backup unit is not plugged into the wall, it runs on batteries. the annoying alarm is buzzing as a needless warning. Other than that, the only other thing to do was to put the whole thing in a waterproof box, and connect the ground wire to a grounding rod in the field. We ran these laptops for years this way. The trick of having two batteries was so that when we were swapping out the batteries on a monthly basis, we could keep one battery connected while swapping out the other. This allowed for the laptops to run without needing to be shut down. Later, around 1997 small 12 volt solar pannels started to show up in local auto parts stores. We bought one and connected that to the batteries as well. This allowed us to run the laptops off-grid for six months until the whole thing was blown to a million pieces by a direct strike of a lightning strike. : ) Also, to charge the spare batteries I was swapping out, I used a second modified battery back up as the battery charger to recharge the batteries. This just needed some longer wires with alligator clips soldered onto them.

[@SuperWiseacre]

This episode is pure gold, I really learnt so much things

[@alerey4363]

Excellent real-world tests and comparison in a key department for SBCs; it also covers both bases: small-portable-lightweight powerbank vs heavy bulky durable lead acid battery

[@Evaldas65]

I was hoping you'd touch on power level sensing (that is, the pi shuts down safely once the power level gets very low), perhaps in part 2 of this video? :)

[@pavan13]

A raspberry pi video after a long time

[@ExplainingComputers]

They always return. :) And two weeks today there will be a Raspberry Pi Pico video.

[@TheTechieScientist]

@@ExplainingComputers Yay

[@horseradishpower9947]

This will be helpful, because it likely help me out in the questions I have in home made portable computing. Thanks for making this video.

[@arthurmint]

im glad you got this video out before the universe came to an end, very helpful !

[@apflewis]

"Lets go and get started", Noooo, I want to take a closer look!

[@lemailpoubel6210]

🤣🤣🤣🤣👍👍👍

[@CTCTraining1]

Yes, but is the ‘closer look’ indicating an unboxing rather than ‘getting started’ on a project?

[@lawrenceallwright7041]

@@CTCTraining1 You've been watching this channel too long!

[@gutwallst6645]

Right!

[@Plasros]

So!

[@parkamark]

Is the lead acid battery going to be re-charged from sunlight in that greenhouse? That would make an awesome little project!

[@volvo09]

Perfect "cheap and easy" chemistry for a diy solar setup or first battery project to get you learning. You can add a cheap pwm solar charge controller and 12v panel from amazon, and in the states you can find those batteries locally in home depot.

[@filthylucreonyoutube]

@volvo09 Right on! I've been doing a bit of that and it's amazing how useful and affordable the new panels and controllers are now. Practical and economical solar power has definitely arrived for low and moderate power consumption projects.

[@ajantis.ilvastarr]

I was acutally thinking about installing Pi in my car connected to power bank which would be charged by solar panels. Would that work?

[@volvo09]

@@ajantis.ilvastarr you could if you wanted to do it for fun, but since it's in a car if you drive the car enough, keep the pi's battery charged when you run your car (and use solar to keep it going for long term storage). use the separate isolated battery for the pi to keep from draining your cars battery. You may be able to get away with keeping it powered off your cars battery alone, but those batteries are not designed to be run down and they fail wuickly with even little draws, so having the 2nd battery would be ideal... Then just pick your method of charging. Your setup would be a smaller version of what rv's use... The main vehicle battery stays seperate, and the house batteries run independently and charge when plugged in or the vehicle is on.

[@theflyingsmiley01]

I have always wondered about powering R-pis with batteries. You did a great job on this video!

[@larrywebber2971]

Immensely and timely video for me Chris. Thanks!

[@mohnkhan]

Lead Acid chemistry is strange yet useful. The rate at which we draw the current determines how much useful capacity you can make of it. May be you should run a video series on battery chemistries and how to select a right battery type. Its an interesting subject.

[@dougcox835]

It is interesting but I think it's a bit of a stray from "explaining computers". I think he has other channels that he might put stuff like that on. If you look around youtube I think you will find lots of videos on batteries. Including people who make their own from individual cells. There's one guy who shows how you can use an old battery case and make your own lead acid battery. It's actually pretty simple, but messy with the sulphuric acid.

[@zackaboy1236]

I’m all up for this but maybe on a separate channel as this channel is mainly for computers/technology.

[@g-r-a-e-m-e-]

@@dougcox835 Who is the person you are thinking of?

[@Aaron-hg8jo]

I would watch that.

[@diogenesdevletoglou6190]

Lead acid is obsolete, bulky and very heavy. Your best bet here is to buy 4 Li-ion 1.5Volt rechargeable AAs connected in series and then add the simplest linear regulator which is just one small resistor in series as a voltage divider. Benefit of Li-ion chemistries are light weight, energy dense, and a very stable discharge curve (

[@ahmad-murery]

Interesting indeed how old-tech lead-acid batteries still performing very well, 14:33 That was a very useful formula to calculate the output amps, for your greenhouse, you maybe can extend your battery runtime by charging it using a small solar panel, Thanks Chris,

[@tomhath8413]

Or just buy another inexpensive battery and swap them out every few days.

[@tanyoivanov-personal]

Thank you. It was useful to me. I thought to use an acid battery and now I know how long should work with it. Great help.

[@techman2471]

You were extarordinarily "Energized" about this project. I learned i can do the projects I want to do on my Pis. Thanks!

[@sandeepkulkarni3695]

Due to low space constraints and Higher Power Requirements of Raspi 4 (1GB RAM) I had to design a converter for 3 Li-ION cells in series (3.7*3=11.1V) and then stepping down this voltage to 5V using a buck converter at nearly 2A! Happy to see similar work Chris!!

[@ExplainingComputers]

We are clearly both on the same page!

[@littlechestnutorchard]

@@ExplainingComputers if anyone is interested Lidl and Aldı sells 20v 4 and 5 Amp cordless tool batteries, the prices are £25 and £30 respectedly, sometimes it comes with charger or if you want to buy it seperatelyi it is usually £12. These batteries are very compact and protection circuits are included in the casing , great for portable, mobile applications. I have been using them last couple of years for remote water reservoir level control and charging them with a small solar panel and very happy about the results .

[@sandeepkulkarni3695]

@Shogun Zoro Sure

[@zackaboy1236]

@@sandeepkulkarni3695 ur not even a good youtuber tho

[@sandeepkulkarni3695]

@@zackaboy1236 Though I am a capable Electrical Engineer

[@slawomirkortas]

This was exactly what I was pondering for a remote Pi setup. But that's half of my puzzle. The other half is a small solar panel installation that would charge the battery during the day. Could you include that scenario in your next video?

[@OriginalRaveParty]

Very handy reference for RPI remote project builders. Thank you.

[@lorderectus1849]

Those spectacles look 👀 absolutely electrifying!

[@gigteevee6118]

Gratuitous use of Mr Scissors! That bag of "magic beans" had a tear option.

[@ExplainingComputers]

Tear options often may a bay more difficult to reuse, and more difficult to control in close-up on camera! :) And Mr Scissors would be upset.

[@Aaron-hg8jo]

@@ExplainingComputers Mr. Scissors is that last person I would want to upset.

[@klaxoncow]

@@Aaron-hg8jo I don't know. I'd be more worried about upsetting Mr. Stanley Knife than Mr.Scissors, personally.

[@adrianschneider1977]

Nice video! According to my knowledge, lead acid batteries should not be discharged below 50% on a regular basis as this would shorten their life. So ideally implement some battery monitoring that prevents too deep discharging.

[@petertwiss4215]

Thank you! A clear demonstration. I did this and then modified to connect to Google sheets though their API. This means that when the power fails, the spreadsheet will not corrupt and also I can view from anywhere.

[@DeusinMachina]

I've been super interested in figuring out the raspberry pi's capabilities on batteries, so this video was perfect!

[@OwtDaftUK]

You can buy a USB cable that has a power switch. Which is good for power since they tend to not do data. It might help with the auto on thing.

[@georgemaragos2378]

Hi, my PI3b+ came with one, when i looked at it i thought very high tech like a bedroom table lamp - but it has its uses

[@markconger8049]

Regarding the small lead acid battery seen in this video they can be found at Walmart stores in the US in the fishing equipment section. Otherwise, I’ve had to order from Amazon.

[@Aaron-hg8jo]

Thanks!

[@ernestgalvan9037]

Walmart, Academy, Tractor Supply, Northern Tools, Home Depot, Lowe’s, Cabela’s. To name a few places that sell those small batteries. They are used in alarm systems, deer feeders, emergency back-up lighting, small trolling motors… etc

[@dakotadanderson]

Excellent forethought on the use case when testing the battery life!

[@spikekent]

Fantastic as always Chris. Looking forward to the remote watering project.

[@jmctoob2]

I am sure you know this, especially since you calculated this for the lead acid. The 74% of listed capacity is because that is the cell capacity at 3.7v. When running at 5v the mAh will be lower by a ratio of 3.7/5.0=0.74. A better capacity rating is Watt hours (Wh).

[@Matbombardier6985]

a small solar panel (something for automotive since its already small, mobile, and setup for 12v... I've seen 'em with banana clips) should be in your near future

[@johnsonlam]

Thanks for the hard work, spent lot of time to get the numbers.

[@marksterling8286]

Absolutely fantastic video, i think you must be a mind reader, I started last weekend thinking about a project to power a raspberry pi4 running retropie in the back of my car, to allow the children to play games on long journeys, the thing i was working on was to have a power bank power the pi after the car ignition was turned off to allow the pi to shutdown nicely. I have designed a circuit that charges the power bank from the car, and the pi from the power bank but when the cars power is lost it signals the pi via a gpio pin to shutdown the pi. Looking at the test results I am tempted to just have the pi’s power from the power bank and then just change the power bank when the car is running. Really great video Chris. Thank you so much.

[@ElmerFuddGun]

_"Usable capacity"_ at 4:39 is not 75% but actually based on the *false advertising* of USB battery pack manufactures. The manufactures get their claimed capacity from the li-ion battery's capacity at a _nominal_ 3.7V *NOT* at 5V. You will not get 10,000mAh at 5 or 5.1V on the USB output. You need to convert that 10Ah (10,000mAh) at 3.7V to watt hours (37Wh) then divided it by 5V (or 5.1V) then multiply by the boost or buck converter efficiency (~87-95%). *Yes, all USB battery capacities should be claimed in watt-hours.* I hope this helps to clarify why you are not getting "10,000mAh".

[@ElmerFuddGun]

Also remember "10,000" can be a model _name_ and is often an approximation of the total of the batteries. Better manufactures will round down while others "round" up quite a bit. Cheap manufactures can also use batteries that vary greatly depending on when and who they got them from so the capacity of one USB battery pack with the same markings can be much different than the next.

[@ahoj113]

19:52 Really looking forward to that! :)

[@conororeilly5492]

I'm really excited to see the greenhouse project video

[@BQQBIES]

Heat death of the universe, I can wait.

[@jub8891]

interesting tests! although running down a lead acid battery can reduce its capacity- will you be using the battery for general rasp pi computing?

[@MrPitki]

My favourite pi video so far! Very useful test indeed

[@henryl200]

this information is so use full to have it was nice that you took the time to figguer this all out.

[@MWPdx]

0:45 Woah! Here I was, ready to take a closer look, and suddenly we're getting started? Idk if I can handle this emotional roller coaster.

[@Felixvioleta]

Now I'm curious how many Raspberry pi's do you even have? and should make a video about it?

[@TheMadRocker]

I use a Pi for ADSB flight tracking. Adding a solar panel and charge controller to a 35amp hr SLA battery has been on my to do list. Thanks for the vid with real world numbers.

[@RaspberryPiGirls]

this video is so professional. I only tried 18650 batteries for my raspberry pi4.

[@jaykayenn]

You seem to have overlooked the capacity calculation for the powerbank, as they are rated at 3.7v not 5v. Otherwise, fantastic video! That surely took a lot of patience.

[@BruceWayneReal]

So you're telling me that lead acid batteries store for ages and you can run a pi with them for ages? Noted

[@georgemaragos2378]

Hi, each product has its own advantage and disadvantage In this case lead acid battery was a similar price to the battery pack and the lead acid unit purchased is able to last 3 times longer The negative aspect is you loose simple portability, while you could mount it all in a small box the usb charger unit can still sort of fit in your pocket or be hand held I believe chris mentioned the lead acid battery will take 12 hours to recharge, i dont know what the usb power bank will require in recharge time but some quick google mentions 2-3 hours So to me if you want portability use the USB powerbank if you want it stationary and less frequent maintenance use the lead acid, is you need it 24/7 then use 2 x lead acid batteries and use battery A when empty plug to battery b then charge A for 12 hours and disconnect - you could do it all with small jumper leads Regards George

[@hansoak3664]

Excellent tests. Thank you for the real world data.

[@Mister_Stork]

Excited for that greenhouse video! 😍

[@warrengibson7898]

My takeaway: the time has come to say goodbye to Fortran and learn Python!

[@hxhdfjifzirstc894]

What's wrong with PASCAL, buddy?

[@David_P132]

Gee do they still use Fortran? I learned it when I first started in IT back in 1971 - thought it would be only a historical curiosity by now.

[@tophlaw4274]

@@David_P132 you'd be surprised that Fortran is still alive and kicking! There are a lot of legacy systems out there as I've recently learned (last year) when an astrophysicist acquaintance asked me if I could look at their system for an upgrade (formula modification) as his programmer was unreachable at the time.

[@ernestgalvan9037]

@@David_P132 ..Lordy, I started on FORTRAN back in 1970… along with COBOL and RPG. Then dived into assembler. All on an IBM 1130… 8k core, 500k single-plater HD. Punch-card. 🤓

[@David_P132]

@@ernestgalvan9037 We're showing our age guys! Back when we learned IT from the zeros and ones upwards eh?

[@alextrusk1713]

I use a zpm from stargate to power my raspberry pi

[@ExplainingComputers]

Ah, a very wise move. I here they last a long time.

[@Dweesil]

This video was great! I found it very interesting. I'm looking forward for the raspberry greenhouse video!

[@Reziac]

Lesson learned: when testing battery capacity vs a low-draw computing device, run that device at max CPU, because otherwise it won't finish until sometime after the heat death of the universe. Didn't know Belkin was making that little power bank; I'm looking for another one so there we go.

[@simpletongeek]

Yeah. I was wondering about that. I'd have the RaspiZero at max CPU and WiFi. Then run a cronjob at every minute and hour logging "date >>hour|minute.log" May even do it every second as well While true: sleep 1; date>>second.log Or something like that.

[@martyburgess341]

Perhaps even add a small solar panel to the greenhouse to make it low maintenance 🙂

[@oznerriznick2474]

Very useful information..thank you!

[@bartniaux8630]

Bonjour Chris. This is a timely video as I am planning to build a local remote power source for my project. I was planning to use a LiPo battery with a solar panel for recharging. This video changed my mind to switch to a lead acid power unit instead of the planned LiPo battery. Great timing. Thank you.

[@bartniaux8630]

@@bgeery Thank you for the info/feedback. Since the Solar panels will be charged daily, I hope that the battery will last longer like in an automobile.

[@commentingpausedtoprotectus]

I now know which battery to use for my long-term raspberry pi 0 lapel camera project, nice one!

[@Boxpeoplez]

This is just the best channel ever.

[@ExplainingComputers]

Thanks :)

[@mgilrosa]

terrific job!

[@cocopalma3072]

Excellent video

[@randallmassey1696]

Awesome! This is exactly the video I wanted to see. Thanks for all you do.

[@philiprobinson999]

Great video, thanks for posting it. I use multiple Pi's to feed adsb data to various sits and found it to be very useful indeed.