Total confusion re: 5V MAX 18650 Li-Ion battery charger with switching jack power

Other Hardware General Electronics
1

Hello!
Apologies in advance because I know this is a dopey question and especially, I don't even know how to correctly ask it...
Anyway,
I was looking for topics relating to what I put into the title here, and did find the following:

The above mentioned a "TP4056" <??> applied to something made in the past by Polulu, but my search on their website was not productive.

What I want to do is like what a phone does, but running a unit (consisting of two ATTiny85 microcontrollers that I program using my Arduino Nano, to control some LEDs), namely:
I want to charge a single 18650 Li-Ion battery while ALSO allowing the above-mentioned unit to function (light-up the LEDs).

That's it.

I do not know how to "remove the parts" from my old Samsung cell phone and get them to function...otherwise I'd try that...

I found a description of the concept here:
switches - Wiring power supply, battery and charger for portable speaker - Electrical Engineering Stack Exchange,
although I only want MAX 5 V and a pre-made "charger".
I looked up the various parts, and tried to learn more, so I could make it, but it turned into an informational rabbit-warren and I ended up becoming MORE confused with each new aspect I found and tried to look up.

To be honest, I don't want to make it from scratch and would be quite happy to at least consider buying one (depending upon the price), BUT all I've been able to find have been UPS units to be used with computers, and some other high-powered units.

So right now, I admit I am totally clueless.
ANY clue as to what such a thing would be called, or a diagram of how to assemble one, or heck, even how to use one out of an old cell phone!, that some kind soul might take pity upon me to offer would be more than I have now.....

Thank you in advance - and apologies where applicable...

The problem there is that I don't even know what a simple 4.7V-maxumum thing would be called... :frowning:

I know what I want to do CAN be done, but I have no idea how to put the pieces together for it to BE done...

2

You might want to look at this module from AliExpress.

https://www.aliexpress.us/item/3256806293904686.html

It includes the TP4056 charger, battery protection, and a 5V boost converter. And it has a "power sharing" circuit that lets you charge the battery and power your circuit at the same time.

It is missing two things. The first is a capacitor across the input of about 100uF, and the second is a power switch. The module has a place to wire in the switch, but doesn't come with the switch itself.

The input is microUSB, but the output is just through-holes to solder wires to. It will supply 1A of current at 5V.

Be sure to get the 5V version ("color") with the battery holder on the back. And then of course you'll need a battery.

Edit: There's a long-winded thread about this board:

https://forum.arduino.cc/t/at-last-18650-charge-boost-module-with-load-sharing/1164462

3

The post #2 is the best answer there is on this subject. Most people answering this will get it wrong. I have been studying this specific application an and off for over two years. I now have the ultimate solution and so do you.

4

Hello ShermanP and THANK YOU for your fast and informative reply!

I opened the links and I'll give them a close look after supper.

Thanks Again!

  • Kris
5

Hello sonofcy, Seeing it all together is pretty amazing, given all the chaos I ended up with while trying to track down all the different bits I saw online...!

I'll be giving a close look after I eat but I'm still at the stage of "Wow!!!"

I guess it doesn't take a whole lot to make me happy, LOL!

Have a good night -

  • Kris
6

I just ordered 10 of the boards for my game cameras.

7

I ordered 10 of the single cell, but now realize I really need 2 or 4 cells for longer life. I am assuming the 4 cell has a single 5V at 1Amp output.

Do you have a link to a board that is correctly made that does 2 or 4 18650 LiFe (3.7) or LiFePO4 (3.2V)

8

And did you order 10 capacitors and 10 on/off switches for the single cell boards?

So far as I know, these boards work only with lithium-ion 18650s.

Here is a link to the two-cell version:

https://www.aliexpress.us/item/3256805009119745.html

The two-cell board does not need a capacitor, but unfortunately it has no provision for adding a switch. That's a major omission because the boost converter will draw down the battery over time even if there is no load current.

I don't know of a four-cell board that works like these.

9

I want to know that if there is any powerful battery charger which tell us the battery percentage. Because I have use many charger for house lithium batteries which just indicate with their light color the charging of batteries.

10

Good Morning ShermanP - Thank you for posting that reminder regarding the capacitor!
I know you were answering sonofcy, but I also found that useful and thought I'd mention that.

I have a number of on-off switches but always am looking for ones that are easy on people's fingers. It's a small thing - no pun intended - but if anyone is making a thing for someone else, it's good to keep "ease of use" in mind.
One of the reasons I wanted pass-through power in fact, is that I have the impression the 18650 cells can pack a bit of a wallop, and I'm hoping that using a combined unit will mean the recipient/end-user will never have to touch the battery at all.

Meanwhile, I also want to say that one of the great things about the links you posted is that after looking closely at the items, and then going back to some of the "piecemeal" information I'd collected, the latter make much more sense now. So you helped me not only with finding a unit I can use, but also, with my learning! :smile:

I'm looking at the cells offered by https://imrbatteries.com which is not all that far from where I live, and recommended by several sources I found online.

Now the "only" thing I need to do :wink: is get all of the textured-glass pieces cut, ground, and assembled, LOL!

Again, thank you!

  • Kris
11

I discovered rather than a switch, a 2 pin header that can have a jumper or not does the trick and is what I will go with.
Remember to get UNprotected cells.

12

The module has protection built in, so you would need an unprotected 18650, preferably a flat-top cell, not a button top. Just be very careful that you don't put the battery in backwards. It's not clearly marked, but the positive end of the battery is at the same end of the board as the USB socket.

Well at least until the battery dies, which would be several years from now, he only has to recharge it periodically.

13

I should mention that both the single-cell and two-cell boards have a power-on indicator LED that you may not need, and it only uses up battery power. If you have on/off switch wired into the single-cell module, then the LED will only be on when the main device is switched on. With the two-cell module, it will be on whenever the battery is installed.

So in both cases, you might want to remove the LED, or just its current limiting resistor. On the single-cell module, it's R9, and on the two-cell it's R8.

Also, here's a modification to the two-cell module that would let you install an On/Off switch. Highly recommended.

On-Off mod for 2-cell module
On-Off mod for 2-cell module840×748 156 KB

14

Thanks again! I didn't even think about getting an unprotected battery! But that does make sense.
This is the problem I tend to run into with making plans first (that moment of "Oh gee wouldn't it be nifty if I did ), and then trying to figure out how to accomplish the goal <ahem...> It's worked out with most things but I'm cautious-bordering-on-paranoid :wink: when it comes to electricity. I remember that amperage is the most dangerous part so it gave me significant pause when I saw the 18650 cells that can push out surprisingly (to me) large amounts of amperage.

The great part of the Arduino world is that there are people like yourself who are generous with their knowledge and patient with those of us who aren't talented enough with math/linear-logic to quite get the "hang" of Electrical Engineering.

Well, so a big "Nichts" on "double protection", Heh! :wink:

I just wish shipping time was shorter.
OTOH, I just at this moment realized that I can make the star with a super-simple light unit and send the "upgrade" when the Module arrives and I get my project-unit assembled :smiley: I've designed it to open up so that should work.

I mention that just in case it might be a useful idea for someone else.

Have a good afternoon!

  • Kris
15

I also discovered that with 18650 batteries if you put the negative end in first then slide the positive end in it will short the positive to the battery case and it will be very loud. I now always place the positive end in first then slide down the negative. It mnay only be certain makes of battery, but once burned etc.

16

Well, you'll probably get a chuckle out of this but actually just ordered two from, of all places!, Walmart...because it supposedly arrives much sooner, and the description seems to mention the same functions. I don't think this one has the indicator LEDs, though; I'll see whether it comes with any instructions, and if so, whether they mention the capacitor. If not, I'll try it with and without.

If it's a "bust", Walmart at least processes returns.
Anyway, here is the link, just in case it's of interest:

https://www.walmart.com/ip/SunyaMood-DC-5V-Type-C-18650-Lithium-Battery-Charger-Board-Charging-Backup-Power-Supply-Camera-Outage-Life-Adapter-UPS-Uninterruptible/13174318515

17

I know nothing about the Walmart module. But good luck with it.

18

Some of the other products the WalMart seller has:

Screenshot 2024-12-05 at 9.21.37 AM
Screenshot 2024-12-05 at 9.21.37 AM2168×820 237 KB

Might make you go hmmm... about whether or not they are a good source. For example, the Cotton Eye Joe Cartoon Plush Chicken. :stuck_out_tongue_winking_eye:
Like you say though, they have a good return policy.

19

I found that module on AliExpress:

https://www.aliexpress.us/item/3256806963661477.html

Potentially it could be good. It has USB-C input, and it has USB-A output. And it has two inductors - not sure what that's about. No evidence of On/Off switch in the pictures.

20

I'm not interested in any of that, AND all sorts of places sell all sorts of things, some of them good and some of them just plain crap.

It's not like I'm too stupid to examine and assess various factors, decide which are and are not relevant to a specific matter, and decide in accordance with whichever factors matter the most to ME.

PLUS, there is absolutely nothing which guarantees AliExpress is any more reliable for the item I want for my project.

But hey, thanks for playing :roll_eyes: