What's the real capacity of Power Banks/ Portable Batteries?

[@RedskullPro]

I am aware that this was not the most scientific testing done and there could have been more ways of finding the exact capacity of each power bank, however, if i would have started talking about watts, Amps, volts, Voltmeters, lithium ion battery cells or lithium polymer batteries, etc this video would get just too complicated for many. This way i was able to show the real life and real day to day usage and power banks capacity (give or take 5-10%).

[@MikeTrieu]

Redskull: That being said, you should occasionally make those "deep dive" videos with a disclaimer for the less tech savvy that the content will be highly technical. We shouldn't always "dumb down" content for the lowest common denominator.

[@RedskullPro]

+Mike Trieu (MegasChara) ive actually talked to an electrician before this video and i have written down over 2 pages of information regarding power banks that i didn't know. I honestly wouldn't have been able to record that video without literally reading from the paper. There is way more to talk about and it's not as simple as i made it sound in this video... But i totally understand what you mean...

[@MikeTrieu]

That's okay. I'm a big boy engineer. I can take it. Then again, I think EEVblog​ is light reading, so use that as a calibration reference 😄

[@MrRemus2509]

Redskull salut o întrebare din tutorial tau am văzut că beelink mini III 2 este cel mai bun la acel Pret.ceva puțin mai ieftin ce îmi recomandați ? pe la 30 sau 40 de dolari mulțumesc

[@RedskullPro]

+Remus Boila salut, si Mini M8S II merge foarte bine, dar vezi review-ul lui pe canal

[@geekehUK]

Quite a few of these look like they're giving their mAh capacity at 3.7v rather than at 5v

[@ayaanjudson94]

i know Im kind of off topic but does anybody know of a good place to watch new tv shows online?

[@melvinatlas8753]

@Ayaan Judson I would suggest flixzone. Just google for it =)

[@justicepatrick6366]

@Ayaan Judson lately I have been using Flixzone. You can find it by googling =)

[@thastinger345]

It is because the LiFePo battery technology used in there can't be discharged below 70%. The BMS within the portable bank prevents you from discharging beyond this point

[@212025510]

This video is very helpful. I have a question though: During my mini web research I found only 20% loss of capacity is to be expected from up and down voltage conversions. So the discrepancy is just manufacture's exaggerations, right?

[@davidbolha]

Indeed. False aldvertising. 😏😑

[@graxaimcongelado]

Friend. Help me here. When you measure the actual capacity in 5V the "mah" reduces, obviously. Buuuut, the cell phone battery is also a lithium 3.6V, then, the conversion back in the cellphone would not give back this total "mah" in 3 6V? Then, the only discounts in capacity would be the electric losses and resistances cable, right?

[@kelvink9999]

best is to use Wh. easy to compare apple for apple especially when you might have diff voltage

[@nitropoweredHpi]

That's why no matter which power bank or power station you measure it will always be around 80% of advertised capacity. A lot of the losses goes from the generated heat, especially with newer devices which are charged with higher voltage and higher amps like Samsung and Huawei. (p30 pro 10v 4amps)

[@gamingenthusiast1018]

Whilst manufacturers will exaggerate the capacity of the battery(ies) they use. There will also be other energy losses. These can include the cable you are using, how fast you are charging, the faster the charge rate the less efficient as more heat is generated. Not only that but the device you are charging might be using power while it is doing so eg a phone. The best example of measuring energy losses I have come across on a test of my own… I bought 2 power banks (they claimed they were 38,800 mah each), they were identical and from the same seller. These power banks had digital displays showing the percentage of the battery not just four or five leds showing in only 20 or 25% increments. I charged one to full and completely depleted the other then I charged the dead one with the full one. The dead one charged to 87% meaning all the losses accounted for 13% of the total capacity. It’s important to note that this does not indicate the true capacity of the battery being tested but the losses when charging so you can factor that in when charging a device with a known true capacity. This should help

[@Nessal83]

Is that why it seems when I charge at higher wattage that I get less amount of charges versus lower wattage? For example, I can get 2.5 charges out of my power bank at 15 watt versus only 2 charges at 45 watts?

[@kiko-lm1gp]

i appreciate the details you go through. good job

[@RedskullPro]

Thanks for watching!

[@vBDKv]

A powerbank is a 3.7v battery, but to charge stuff over usb you need 5v. So lets say you have a 20000mah powerbank and you need to charge your phone which has a 3400mah battery. In simple terms: 20000 ÷ 3.400 x 0.7 == 4 charges. That's a total of 13400mah, not even close to 20000.

[@loucipher7782]

then will those phone to phone wireless charging lose out 30% battery too during charge?

[@AchmadBadra]

Wireless charging is more worse.

[@msdoorbonilla5742]

Thank you Alex! That was a very informative video about a subject that I have not yet seen on here or anywhere else. Again I thank you for that video. Sincerely yours, Msdoor

[@RedskullPro]

im glad you found it useful! Thanks for watching!

[@sweetlittlescamp]

Thank you! I was really new at power bank rated/Real capacity and your video has been very helpful! 😊

[@tonytschanz5642]

thank you for making such an informative video!

[@Amir-dm6tf]

You have no idea how helpful this was thanks you very much

[@nigelh3253]

Wonderful! Fantastic! The myths about powerbanks exposed in this short, simple video. And the moral is - bigger is better!

[@RedskullPro]

My girlfriend says the same 🤣

[@rhettoracle9679]

Good work Alex! This topic is rarely discussed. Many cheap devices over claim capacity and under deliver. Anker seems to be a better brand than most. A USB voltage meter is a cheap device to test chargers, cables, power banks etc. Most assume everything is interchangeable, but that's not true and the USB power meter can help you identify what might cause problems or shorten the life of your battery or device if battery is built in. Even more important if your device is quick charge. Long and slow is better to prolong a battery.

[@RedskullPro]

Im glad you liked it. Well it isn't discussed too often because for sure you won't get to work with those manufacturers again :D I can only imagine they emails ill get on Monday when they see their products in there :) Personally i love power banks and i don't really care that much about the capacity.... they are very helpful in many situations.

[@rhettoracle9679]

Agreed, camping and power outages come to mind. I live on a sailboat, have a generator, but for short term power outages, power bank is nice screen time. LED light and USB fan...

[@RedskullPro]

Oh man, living on a sail boat! How cool is that?! Dam, Im jealous! Yeah, i use power banks for a lot of things. For example i use the big "22000mah" ones for charging the cameras while recording, very convenient not to have a cable on the floor

[@rhettoracle9679]

I use a nylon case on a carabiner on my belt to carry my phone and or 7" tablet. Bluetooth earphones, a small USB cable, a folding stand and a credit card size power bank are always in it.

[@rhettoracle9679]

Also run my Amazon dot on a power bank for outside music.

[@bibianakueh1737]

Super helpful and easy to understand for a powerbank novice! thank you!!

[@RedskullPro]

Such an old video :) Thanks for checking it out!

[@ib516]

You need to buy a USB power meter/monitor. Makes tests like these so much easier. It will monitor how many mAh pass through it.

[@RedskullPro]

yes, that would have been the easier and probably more accureate way :)

[@edrumsense]

-How to calculate real capacity *PowerBankCap x 3.7 / 5 * 0.81 = Real mAh delivered* -Where: 3.7 is the actual voltage of the inside batteries, 5 is the voltage output of the power bank, 0.81 is a PowerLoss Factor because the powerbank and the charged devices are not 100% efficient. that will give you an approximate of the real mAh it will deliver. In fact, the picture at 3:00 is giving you very accurate details, it's saying that its capacity is measured at 3.7V, and it gives you the amount os Watt*Hour it will deliver.

[@RedskullPro]

cool

[@DownhillAllTheWay]

I just came across an advert on Ebay for a 900,000mAh power bank for £12.95. This was obviously fraudulent, so I looked up "900,000mAh power bank", and found them all over the web. It could be that they have batteries that will give 900Ah at 0.1V, but the device is a USB charger, so anybody buying it would expect to get the stated capacity in Ah at 5V. No non-technical buyer is interested in what the device has inside it - they want it for what it can do for them - and anything it does has to be done at 5V. This sort of marketing hype is pure fabrication. Surely there are laws against this sort of thing? Anyway, why don't they use Wh to state capacity - then it's independent of voltage?

[@MrXaresx]

so what s good powerbank brand?

[@davidbolha]

There isn't. They all lie. 😒 Just instead buy yourself a 18650 power bank enclosure off eBay & disassemble a laptop battery to extract those cells (& put them in your enclosure that you purchased). 🤔😏

[@johnfish1194]

Just saw one that claimed to have NINE MILLION MAH. LOL. it was the size of a smart phone.

[@jamesalexander9870]

really love your effort for this video! keep up the good work, i'll be waiting for more :)

[@RedskullPro]

Im glad you liked it! Yeah, took quite some time to discharge those powerbanks!

[@spikep5r]

I got an Asus 10000 mAh power bank, it charges my S7 Edge for like 2 and a half times, which is really great giving the fact that the phone battery is 3600 mAh. However, when I charge it using the power bank, I tend to turn off any consumer like wifi, bluetooth, background apps and sometimes the phone itself (or put it in airplane mode).

[@RedskullPro]

+Ionut Dumitrescu brand names usually matter for power banks :) you lose very little compard to the ones i have here. The worst one was that 12000mAh Poweradd that lost almost 50% of the capacity.

[@stateg2]

Thanks for your video. It was very helpful, as I am buying a power bank for the first time.

[@RedskullPro]

Glad it helped

[@thenewgametv]

I'm so glad the I find your channel!!

[@ilaneanisaliane1898]

Found*

[@RedskullPro]

Im glad you liked it, thanks for watching!

[@thatguyfromca]

Can you verify the volt convertion?

[@TomPark1986]

They should only put the rated capacity on the battery.

[@peter_s]

Thank you very much for your easy to understand explanation.

[@carlos.deoliveirafilho]

someone knows where i can find a powerbank showing it's real capacity ? hahahaa

[@RedskullPro]

get any of them take 30% off and you know the real capacity :D

[@carlos.deoliveirafilho]

got it.. so I guess the calculation is like: (3,7/5,1) x (capacity showed in the ad)

[@douglas2510]

Is the moon.

[@universityofthrifting709]

Very informative.any lithium batteries Power Banks?

[@RedskullPro]

I haven't tried any

[@LupulTaz]

Thanks for a very good explanation and clarification about how power banks works. Very useful !

[@RedskullPro]

Thanks for checking out the video!

[@RythaSherrie]

Thank you! Wish you did for Oraimo 20,000mAh

[@cjdelphi]

ok, these power banks are delivering what they claim, a 20,000mah bank supplies 20,000mah at 3.7v once you boost you might see an 8 to 18% at most power loss stepping up to 5v for example 5v 1amp for 1 hour is 5watts, but at the battery end it would be 3.7v 1.35ah but the wattage is 5w, you'll find all your measurements are way out and they do deliver what they claim

[@danyala.1659]

Almost 30k subs, video has been out for like 10 minutes, and no views? I did not think this was possible.

[@RedskullPro]

KZbin counts in slow motion :)

[@msdoorbonilla5742]

You're more than welcome, Alex!!!

[@To_Anything]

Dont forget that brand new lithium batteries need to be worn in first, if you discharge and recharge each one 9 times you should reach the full potential of the battery

[@nicknice7580]

Interesting and useful video I never seen or hearing someone talking about this

[@RedskullPro]

Im glad you liked it :) Thanks for watching!

[@Malcolm_99]

Nice 33 hand signs

[@RedskullPro]

Could have been 40 or more

[@nikobelic6822]

then if you have build in cabled do you still waste power my thinking is there isnt usb cabel so it dosent need to change volts to 5 volts and to 3.5 again

[@RedskullPro]

but how do you power the device if you don't use a cable?

[@wjdc893]

Thanks for responding so quickly.

[@soempaing2436]

Will you be reviewing xiaomi bluetooth sport earbud?

[@RedskullPro]

+Soe M Paing im not sure yet...

[@hermifelder93]

super review ! hvala lepa

[@RedskullPro]

+Hermi Felder im glad you liked it, thanks for watching

[@IceAge20017]

I bought a 30,000 mah power bank from China, it's real capacity was 3,120 mAh. Lol. A loss of almost 90%

[@RedskullPro]

oh...!

[@thomasknight7734]

they lose some of the charge between the battery and the phone as well

[@RedskullPro]

+Thomas Knight yeah, you are correct

[@thomasknight7734]

they seem to lose around 30 percent efficiency I have a battery pack that probably puts out about 500 mAh lol it was just a pound in England

[@RedskullPro]

+Thomas Knight for for that price you can't go wrong!

[@thomasknight7734]

Redskull yeah lol I'm thinking about keeping the motherboard and replacing the battery with a bigger one

[@newsofthenerd]

Why you didnt open them up and see what the battery inside said. Because most just outright lie about there capacity

[@propfella]

Why are you adding what you lose during the recharging cycle? It makes no difference what's lost here, as long as the battery is fully charged, so what? It has no effect on it's charging capabilities.

[@R1_R]

Mann you should check out anker battery pack. My favorite brand of choice

[@RedskullPro]

+Radwan yeah, i heard that they are great

[@apurbapal1245]

Power Bank capacity review Gionee sansui

[@joybryant7001]

Great information very knowledgeable great job

[@RedskullPro]

I forgot that I made this video! Thanks for watching!

[@olivermadrigal4794]

Good vídeo bro!!!

[@RedskullPro]

+Oliver Madrigal hey, im glad you liked it! Thanks for watching!

[@danielmendelson6408]

No xiaomi mi power bank 20000mah?

[@RedskullPro]

i had that one at my parents place and i didn't feel like driving to go get it :)

[@anacronic5182]

Ești roman?

[@RedskullPro]

salut, da

[@wackyjacky7259]

Woooooow this video is a god sent. Thank you for doing this research

[@khinmaunghtoo-eb6mm]

Very useful information, Thanks 🙏

[@RedskullPro]

Glad it was helpful!

[@abobader4283]

Thank you! now I understand why this issue happened 😂

[@ahmd5]

Thanks..simple and helpful

[@RedskullPro]

Thanks for watching!

[@garrickkidd4508]

Soo we can conclude that every power bank has a 30% power loss, minimum. ... Damn

[@RedskullPro]

wow, I forgot I ever made this video! But yes, take about 30% from the capacity and that's what you get in reality

[@melllanes5574]

Great video again!.

[@RedskullPro]

Im glad you liked it! Thanks for watching!

[@therandomman2971]

The way you tested them is wrong, the capacity you got us way less than what the batteries probably have in them. The method isn't accurate because of the phones consumed power while they are being charged. The battery capacity indicator on your phone is a rough estimate. It's good for you, but really bad for calculations. What you could have used is one of the "Charge doctors" from ebay. They are decently accurate. There is a loss when ~4v from the power banks battery is boosted to 5V to the USB output and inside your phone it is stepped down to charge the internal battery. It is because of these losses that even if the battery is 20 000mAh it cannot charge a 5000mAh device 4 times.

[@RedskullPro]

this type of "testing" had nothing scientific about it. I thought about how it would be the easiest way to present the information without confusing people talking about watts that are amps x volts, etc. I thought that this was the simplest way to explain how this would translate in real life usage :)

[@SagarPatil-jr3bu]

Good to see different kind of video Great :)

[@RedskullPro]

im glad you liked it! Thanks for watching!

[@habeebsulaiman6167]

Very helpful video

[@RedskullPro]

Glad it was helpful!

[@1945herb]

Hello Alex, I enjoy your channel very much,you give great reviews, this topic is very interesting as I was always looking for away charge my cell phones half way through the day, now I use a auto ESP multifunction jump stater and get 3 charges plus when my phone runs out of juice , for $60:00 your can't do better right now.

[@RedskullPro]

great price considering that some of those power banks in the video were close to $50, thanks for sharing!

[@billaras41]

excellent as always!!! thank you for the info my friend!! now we know what is going one with the power banks !! I was so surprised to find out that really 30% we loose from the power bank when we charges a smartphone!! so far I was believe in that we loose around 5 to 10% wow impressive! ""!

[@RedskullPro]

before i started charging all those phones and tablets i thought the same...a maximum of 10% would be lost...but no...not even close. I almost feel that they should increase the capacity by 30% and mark the products with the "real life" value

[@propfella]

His math and electronics is sadly lacking. As I said previously, what's lost during the power bank's charging cycle has no effect on it's ohone's charging cycle

[@propfella]

@@RedskullPro Chinese sellers and Real Life don't mix. They will overstate everything they sell. It all started with NiCad Batteries and they've done the same thing with everything they've manufactured ever since.

[@andrewsilver7048]

Doesn't seem like a reliable test.

[@RedskullPro]

life isn't reliable

[@bvalkyy]

Ok , the producer write the capacity at 3.7 v and you obtaine 10000 capacity. Of course is a marketing strategy. Some onest producers write also the rated capacity , wich in my case is 7000 mAh at 5 v (TYP 1A) . So i have a 10000 mAh capacity battery at 3.7 v rated at 7000 mAh 5v ... 1A discharghing . In fast charghing mode the capacity 2A or 2.1A is even smaller , probably due the heat disipation . Also my battery say it support max 3.6A , which i belive because the battery turbocharge my phone , and my power adapter only fast charge my phone ( the phone came with a 18 w adapter ..but suport a 27w one ) So in this case the capacity is decreased again . Of course in time the cells loose their capacity , and if you have a 4000 mAh phone like me , you will be able to fully fast/turbo charge one time from 0 to 100 with a " 10000" mAh battery .

[@vishalagrawal8717]

Thanks for info bro...

[@RedskullPro]

+vishal agrawal thanks for watching!

[@ridicuze9065]

great video

[@alexs7491]

900000mAh Power Bank Portable sounds legit? they are on ebay

[@RedskullPro]

haha, i am sure that's a typo

[@abghere]

Great info!

[@RedskullPro]

Im glad you liked it, thanks for watching!

[@arkaleon1551]

Informative Thanks

[@oq2319]

How can I know the mAh capacity of a chinese power bank? because they always lie to their capacity, I know they have more sophisticated methods that uses a usb but I was wondering if I use a 1amp charger to charge a battery of a 3000mah cell phone and it takes 3 hours to charge (5v common charger) or be charged 1000 mah per hour could i find out the capacity of the power bank battery by the charging time of it? type if I use a 1amp charger and it takes 5 hours to charge 100% it would have 5000mah would not it? Of course this capacity would be from internal batteries to 3.7v and not from the actual carrying capacity with conversion to 5v which has a loss ....

[@INTEL965GAMES]

I love watch some people that use Power banks EVERYDAY, EVERYTIME...This Powerbanks are for EMERGENCY ONLY...I use it for Emergency Only not for PUT THE PHONE with him everyday....

[@RedskullPro]

a lot of people use them for many purposes. They are great if you are doing a time laps somewhere and you have the camera on for a few hours...they are useful for many things, but again, this is just a personal preference.

[@INTEL965GAMES]

I use this sometimes and if you continues using this everyday as NEW EXTRA BATTERY could be dead you batterry..I am not a person who is on the phone all the fcks days..Srry bad inglish

[@jjarry]

gfrp There nothing what say it only for emergency. You can use it as much as you like. Just cause you don't go on Facebook all day . Dose not mean other people can't.

[@wjdc893]

...but you didn't recommend the best one, c'mon. !!!

[@RedskullPro]

i use the 22400mAh EC Technology ones. I have 2 of them :)

[@arocomisgamusclademork1603]

Cheap powerbank loss true max capacity, what's difference buy Powerbank expensive price instead common marketing unlike Ankery?

[@65nightsofstatic]

You have a bit of Bulgarian accent

[@RedskullPro]

Just a bit? :) It is in fact a Romanian accent

[@65nightsofstatic]

Redskull 😀 at least my guess was geographically close enough

[@RedskullPro]

+65nightsofstatic yes, very close :)

[@jamiesucks7994]

That's because batteries degrade over time!

[@RedskullPro]

They were all new

[@thomasknight7734]

I tested my battery i got from pound land It had a whopping 520 mah Impressive, I know

[@RedskullPro]

+Thomas Knight wow! :) i could probably charge my phone 10%

[@thomasknight7734]

Lol yeah It works in a pinch but then again it was just a pound so what do you expect lol They advertised it at 1000 mah so that's a bit disappointing

[@thomasknight7734]

Redskull what phone is your daily It's the umi mix right?

[@RedskullPro]

+Thomas Knight you mean the Xiaomi Mi Mix, yes that's what i use now

[@thomasknight7734]

Yup

[@freesaxon6835]

You have been busy,! must be like a holiday away from those TV boxes I have heard that the Anker Power bank is good ( but expensive)

[@RedskullPro]

Yes!! it is like a holiday on the beach somewhere! :) I couldn't get a sample for review from Anker :)

[@Colinobi]

interesting video very useful

[@RedskullPro]

Im glad you liked it, thanks for watching!

[@gurjeetsingh8743]

You are great 👍

[@Pochoco310]

Excellent video.

[@RedskullPro]

me alegro que te gusto :)

[@paradox6736]

Русский?😂

[@bengure7766]

👍

[@wesjales5578]

Powerbank have about 30-40% inefficiency rate.

[@RedskullPro]

+Wesley Crabajales pretty much

[@TechSathvik]

First

[@RedskullPro]

indeed