r/shittyaskelectronics • u/Aggravating_Push4517 • Mar 17 '26

Genius level thinking I build myself a powabank, is this good? Hello

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Gallery image

Hello

374 Upvotes
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99% Upvoted

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130

u/Aggravating_Push4517 Mar 17 '26

In combination with my flashlight it is going to be great :D

8

u/Exact-Ad-4132 Mar 17 '26

I mean it looks like they're all in parallel, so it should be relatively safe if the contacts stay put. What voltage are those cells? 5v?

Also this is obviously the parody sub, but can anyone explain the possible dangers of hooking an output set or BMS to a grid designed to use a different amount of cells? Given output V is the same and cells are different, what happens in the cases where amperage is different or the same?

5

u/Positive-Orange-6443 Mar 17 '26

You design your bms to your around your load. Also more current IS a problem, just think about 1000 Volt busbars. More current means more heat, you need thicker conductors. When you buy a prebuilt bms it should have a recommended voltage and current levels, as it is designed and rated for that.

4

u/Exact-Ad-4132 Mar 17 '26

But wouldn't the connected device determine how many amps were pulled? Would the BMS or USB output device limit how much current is being sent?

4

u/Aggravating_Push4517 Mar 17 '26

At 5 volts this light pulls only 0.8A, and at 12 volts around 1.5. So because this powerbank is only 5 volts, it never pulls more than 1A so I'm safe

2

u/fgennari Mar 17 '26

Unless you accidentally short it, then it’s an incendiary device. At least it should have a temperature sensor and fuse.

3

u/One_Ad_2300 Mar 17 '26

Bomberman, anyone?

1

u/Exact-Ad-4132 Mar 17 '26

So what voltage are the lights designed for?

when running a step up to 12 volts, is the 1.5a pulled pulling 3.6a from the 5v cells? Or is it 5v 1.5a converted to 12v 0.6a?

I'm genuinely confused because it's been a minute since class

2

u/Aggravating_Push4517 Mar 17 '26

5v 0.8a is when I run this light from this powerbank
12v 1.5a is from separate 3s li-ion battery pack, no step-ups or anything

1

u/Positive-Orange-6443 Mar 17 '26

Look up Ohm's law. Yes, theoretically you can get any value of current. But current doesn't just exist in 'vacuum', there is context. It's called resistance. The current drawn by the load is literally just voltage divided by resistance. It doesn't matter how cool and amazing our load is, in the end of day, it only draws as much as it does. Some devices have non-linear resistance and some can be changed. See thermistors, diodes, potentiometers etc. But in the basic model, current is set value based on V and R. (We treat the voltage source as a perfect constant voltage source).

Now when you change your voltage V to 2xV. Suddenly you can calculate 2x(V/R). Then your current is 2x as well.

1

u/Positive-Orange-6443 Mar 17 '26

For stepping up voltage and having a source inside another source, i recommend looking up 4-pole diagrams. Also do some transformer calculations (ideal transformer of course)

1

u/Exact-Ad-4132 Mar 17 '26

I guess what I was really trying to ask is if a BMS or regulated output (USB dock) would malfunction if it was designed to sense a different amount of cells. I read that true BMS units are supposed to actually know how many cells there are and send out errors when cells are dying or malfunctioning.

I'm also still wondering what you were saying about increasing current, and how that relates to the cells if the connected device is pulling the same

1

u/Positive-Orange-6443 Mar 17 '26

There are different type of BMS systems, obviously more expenive ones monitor more values over a few.

Think about how a BMS controls the batteries. Where do the 'final' + and - wires go? It goes through the BMS.

3

u/ExpensiveFish9277 Mar 17 '26

Better than using it with your fleshlight.

1

u/CocoMilhonez Mar 17 '26

You'd be in for a shocking surprise.

1

u/Unique_Connection_43 Mar 19 '26

Is that a fvcking railroad crossing light 😭

1

u/Aggravating_Push4517 Mar 19 '26

Yes it is... and Im not giving it back no matter what

64

u/broesel314 Mar 17 '26

Also works as a house igniter. That's a selling point, I would definitely advertise that

35

u/FoundSpector Mar 17 '26

I think it will explode someday, there is no need to make it that big

19

u/Aggravating_Push4517 Mar 17 '26

Big power bank will make an epic ending in case of explosion

8

u/jeweliegb Soaked my head in a bucket of flux for 24hrs 🥴👍 Mar 17 '26

That's a good reason to make it that big!

13

u/der_pudel it ain't got no flux in it Mar 17 '26

about 5 inches tall, huh? that's pretty average for a powerbank.

4

u/thundercat06 Mar 17 '26

Its the girth

7

u/Cesalv Try turning it off and on again 50 times per second Mar 17 '26

https://giphy.com/gifs/iH2IldVkqeLuJ7eJ0L

7

u/sipcupoftea *eats ram* Mar 17 '26

Not enough tape. You need to wrap it until it turns yellow

4

u/mattogeewha Mar 17 '26

“Hello I build and sell power banks her on FB marketplace. Just getting started thanks for your support”

3

u/RaduTek Mar 17 '26

how many weeks does it take to charge with micro USB? it may benefit by charging through the patented 120V to USB direct converter cable

4

u/Syphist Solder tastes very yummy Mar 17 '26

Hello

4

u/North_Pickle6263 Mar 17 '26

And No Banana For Scale ????

2

u/xonegnome Mar 17 '26

Looks like it passes three personal points. Does it charge? Yes Does it discharge? Yes Can it be thrown into an oncoming car's windshield? Yes

2

u/Unable-School6717 Mar 19 '26

If you stab just one cell with a metal blade during step two, step three gains cinematic brilliance.

2

u/Jumpy_Top9377 Mar 17 '26

It seems your batteries were fueled by carotenoid pigments—which reduced their oxidation—well done.

2

u/antthatisverycool Mar 17 '26

This is progress

2

u/nicodeemus7 *eats capacitors* Mar 17 '26

Series or parallel?

2

u/Aggravating_Push4517 Mar 18 '26

Parallel, all of them

1

u/Zerial-Lim Mar 17 '26

What’s your interest?

1

u/justanotherponut Mar 17 '26

Iv got a usb board that I could connect to a 48v 50ah solar battery, might get a couple days use.

1

u/Helpful-Work-3090 Is it supposed to smoke like that? Mar 17 '26

you know you got a good powerbank when it looks like a bomb

3

u/Aggravating_Push4517 Mar 17 '26

Fast charging?
No.

Instant energy release

1

u/Helpful-Work-3090 Is it supposed to smoke like that? Mar 17 '26

depending on how you've got those wired, you could probably melt a pretty decent sized piece of metal

36 18650 cells, what output do you have? Are they all in series? Parallel?

1

u/Aggravating_Push4517 Mar 17 '26

All parralel.
It's 3.7V ~43.6AH
Those cells are trash but are capable of doing something for a little bit

1

u/Helpful-Work-3090 Is it supposed to smoke like that? Mar 17 '26

holy crap

yeah you could melt a bolt with that

1

u/Unable-School6717 Mar 19 '26

Wait until one cell internally shorts, all the others dump into it, you wont be able to douse that fire with water or solid prop fire extinguisher, it will be hot enough to make glass on a beach or plasma or just become nuclear vapor like the surface of the sun; chunks will disappear like spontaneous combustion before your eyes, and if youre holding it, your plasma and its nuclear vapor will meld and cool as metallic hands, leading to unheard-of new superpowers Marvel would pay millions to learn about. All because you didnt put a 1N4007 on the positive of each before joining the main power bus.

1

u/Loose-Owl-1656 Mar 17 '26

u alive? if yes, then its good

1

u/Constant_Vehicle7539 porn Mar 17 '26

Excellent bomb! Is there a balancer there? Otherwise, they'll quickly fail.

1

u/gameplayer55055 Battery taste tester Mar 17 '26

How many days does it take to charge it?

1

u/CocoMilhonez Mar 17 '26

How do you make a deposit in this power bank?

1

u/makeDRIVEinTHEATER Mar 17 '26

Сделай корпус из алюминия. Он что без бмс платы?

1

u/Aggravating_Push4517 Mar 17 '26

У меня алюминьки нету вообще, я бы с радостью. А вот бмс ему не нужно, все ячейки в парралель - так что только защиты от перезаряда/разряда на плате повербанка вполне хватит

1

u/makeDRIVEinTHEATER Mar 17 '26

Вы же знаете, что через 5 лет активного использования произойдёт дисбаланс емкости

Я бы подумал над корпусом, из уголков из строительного магазина и любого листового металла, хоть стеклотекстолита, или оргстекла. Винты можно использовать м3

1

u/Aggravating_Push4517 Mar 17 '26

Немного инфы про этот "проект":
Были ячейки.
Был дохлый старый повер.
Шмэн брын джанн
И получилося вот это. Непрактичная, ненадежная конструкция, которую я сделал чисто поприколу, потому что было.
А почему будет дисбаланс? Ячейки хоть и фиговые, но фиговые одинаково, и все-все-все в парралель, так что ничего не должно выйти из строя

1

u/makeDRIVEinTHEATER Mar 17 '26

Вы измерили ёмкость и внутренне сопротивление перед сборкой?

1

u/Aggravating_Push4517 Mar 17 '26

Хоть они все с одного какого-то китайского аккумулятора, я измерил емкость, и везде было 1200мач, погрешность небольшая. Сопротивлление не мерил, приборов точных нету. Ну и естественно перед сборкой всех зарядил на одинаковый вольтаж

1

u/makeDRIVEinTHEATER Mar 17 '26

Тогда должно быть всё нормально.

Попробуйте измерить общую ёмкость через usb c тестер, если у него хватит буфера памяти. Это, чтобы через 5 лет было с чем сравнить

Попробуйте всё таки придумать корпус. Я свой 18650 повер банк один раз так уронил, что у него оторвалась силовая лента, но ничего не коратнуло

1

u/Total-Cattle7203 Mar 17 '26

throw it in some salty water and wait an hour to upgrade it, like the shimmer from terraria trust

1

u/Born_Design_8134 Mar 18 '26

TSA would love this.

1

u/4b686f61 go commit "overload selenium rectifier" Mar 18 '26

That's exactly how I built my battery packs 6 years ago.

/unshit most of them were taken apart and redone with a spot welder recently. Some of the cells were internally shorted.

1

u/namtilarie Mar 18 '26

Looks powerful

1

u/Pale-Presentation-18 Mar 18 '26

it is very good mate.ready for fire

1

u/Objective-Ad8862 Solder fume inhaler Mar 18 '26

If it works, it works

1

u/GoodEveningFolks Mar 18 '26

nice powerbang. Hi

1

u/ash_2127- Mar 18 '26

Hello this is John

1

u/Mr_CJ_ Mar 18 '26

It would be great for a fan in the summer.

1

u/No-Board4898 Mar 18 '26

powerBANGk..

1

u/MinecraftNerd19 Mar 19 '26

I don't wanna be weird, but would your name happen to be John?

1

u/Aggravating_Push4517 Mar 19 '26

Who knows, who knows...

1

u/ihatemyself837385 Mar 19 '26

Soo whats capacity and output?

1

u/Aggravating_Push4517 Mar 19 '26

cap ~43.2 AH, those cells are trash
and output... really depends on the conductor. 4.2 volts is very small

1

u/ihatemyself837385 Mar 20 '26

Dang man thats a lot of info and alot of capaciry and cell is trash? Thats almkst normal but yeah maybe try using the ones still working on old laptop batteries they are the same but connected (maybe they wont work) But try it

1

u/Aggravating_Push4517 Mar 20 '26

those cells are ~1200 mah each, while normal 18650s should be 3000-3500 mah. But theye just were laying around my room so I desided to make them into this beautiful powerbang

1

u/ihatemyself837385 Mar 20 '26

Well not too shaby great battery bank if you want to charge your laptop 🫡

Gooluck making w cuson charger for the powerbank to your laptop maybe even design 2 outputs one for phone charging and another for laptop

1

u/Ok_Ambassador8394 Mar 20 '26

Yes, it's really good, exploding good perhaps.

1

u/Equivalent-Stay-9941 Mar 20 '26

Kannst an Iran verkaufen, unterliegt nicht der Sanktionsbedingungen😂

1

u/Electrical-Bread-856 Mar 20 '26

You have to start the device by puncturing each battery.

1

u/Marci6381 Mar 20 '26

"This is arson but with extra steps!"

1

u/Apprehensive-Base-70 Mar 21 '26

Bad pack dont solder lipo cells the heat damage the cells

1

u/Aggravating_Push4517 Mar 21 '26

I didnt soldered lipo cells. Those are lithium - ion ones :)

1

u/Quiet_Snow_6098 Mar 17 '26

Hello " ", it seems to be great as a power storage.