Testing questionable LiPo Battery Charger Schematics I found on the internet!

You can get some decent LiPo chargers here (affiliate links):

Websites which were shown in the video:

In this episode of testing circuits I found on the internet I will be having a look at LiPo battery charger schematics. I will build up 2 very simple circuits which claim to charge a LiPo battery and test whether they can truly do that. One circuit is based around an LM317 adjustable regulator while the other one is based around an Op-Amp. I will show you the flaws of those simple design and while I am at it also show you my own super simple, very inefficient but safe LiPo charger. Let's get started!

Thanks to Altium for sponsoring this video.

Music:
2011 Lookalike by Bartlebeats

0:00 LiPo Battery charging in general
1:45 Intro
2:25 How to properly charge a LiPo battery
3:56 Testing circuit 1 (LM317)
7:58 Testing circuit 2 (OpAmp)
10:20 Making my own LiPo charger (CC/CV)
11:49 Verdict

[nothingtoseehere]

"Hold my beer, while I draw it up". Love the channel.

[jfk]

I find it kinda odd that Altium Designer gets marketed to makers. Like 95% can't afford it anyway!

[Asu]

GreatScott! "Which of these schematics should I pick?"
Donut Science: *exists*
GreatScott! "Donut Science it is!"

[navidmafi]

wow i was waiting for another video from "found on the internet" series. Great video!

[fiordhraoi]

I appreciate this, especially as a novice. It seems like the bane of all of my projects is trying to fit in Lipo charging/protection boards + a boost/buck converter, so I can understand the temptation to try to find an alternate approach. The fact that I am looking at making wearable things minimizes that temptation to move away from safety, though. :)

[KamranKhan-coox]

Scott can you please make one such video for audio amplifier circuits found on the internet?

[blanana_m]

Everytime I circuits built without a board, it makes me nervous as hell
one wire shorts and the whole thing just blows up

[Kyuunex]

Meanwhile ebay sellers: **wiring the USB plug directly to the battery**

[sunilkulkarni]

WAITING FOR GREAT SCOTT TO UPLOAD AND HERE WE GO!!!!

[chrisellingson]

I was going to say working with lithium is more nerve-racking compared to mains supply. 😂

These are missing an important feature; charge termination based on the cells specified termination current. If left in CV the cell will heat up, overcharge and swell/pop a CID.

[SirDella]

I'm glad the lovely tp4056 module exists, I'm using one as I watch the video

[Boogie_the_cat]

I really appreciate this topic.

The fire with lipo batteries is bad enough, but the huge amounts of toxic smoke they produce is another huge danger.

I see a lot of youtubers treating lipo batteries very casually, using very dodgy practices and not taking the risk seriously.

i have firsthand experience with a lipo battery fire. thank goodness, it occurred outside (due to the smoke) but wasn't near flammable vegetation.

[Katupiry]

With a single extra resistor on your Comparator charger setup, you can create hystheresis and end the oscillations.
Usually CV charging stages inside dedicated IC's are implemented in a similar way inside the chip dye

[princebanini]

It is always most important to understand how a circuit works before using it. That was cool

[iamdarkyoshi]

Isn't an "anti trickle charge" cutoff an important part of lithium charging? I thought that leaving them on a CV source for a while can cause issues, which is why the tp4056 shuts off once it decides the battery is charged

[Freenormable]

You sir are my favorite souce for information and learning. Thank you for your time.

[yigitsubutay]

Examining ccts, making some improvements this concept is very helpful for beginners and college students. I hope you continue this series. Thankss

[Eagle-mdku]

Please do more of this!!! Totally love these videos! You're sense of humor comes out and makes the video very fun to watch

[PaintmanJohn]

Dead Bug style would be better than all those parts suspended in MID AIR. I like to build ONE OFF designs without a breadboard. Simply mount your biggest parts that will support others to a piece of perf board, or even a sheet of plastic. I have used Double Sided tape, hot melt glue, Super Glue, NYLON nut & bolt hardware, and even just solder to hold parts to a copper sheet. Also makes a great RF shield. Others have used a piece of wood or GLASS to support parts, as well as insulate them. Some groups even get together for "UGLY CIRCUIT" CONTESTS ! Any takers ?

[fabianrudzewski]

Those lipo batteries should have a charge C rating printed somewhere. You get the max charge current by multiplying with the capacity.