Altoids tin charger mod - (Pic heavy)

One of my inspirations in fact! I actually was planning on using one of those chargers, but changed my mind after buying one from RMM

I had a similar thought but I don’t know if it’s really a concern. Both TP4056 boards push current into the battery at a max of 1A with the chips regulating the flow. Just as long as your USB charger can provide the full 2A I don’t think it’s an issue. From what I gather the chips step down the current as it approaches the cutoff as well. With both in parallel it simply means it’ll get to the cutoff voltage faster with higher current (still below 2A total). I was concerned that power would feed from one board to the other but then I thought the battery could just as well do that with a single board especially if you want to charge a fully charged battery. Then I thought what if both chargers terminate at slightly different voltages? Then I realized that probably didn’t matter either since it would simply mean one charger would stop before the other. I think putting in a USB meter alleviated a lot of concern with initial testing and configuration. It’s not necessary anymore but it’s nice to see the validation that it’s still working. Housing it in an Altoid’s metal container would just be extra cautious. Great work!

I bought 2 types of “TP4056” boards before realizing that there are fake 4056 chips out there. I’m ordering a 3rd batch off of Aliexpress now to see if there’s any difference. (Can’t beat ~$1 for 5 boards shipped). I built my own 10180 charger replacing the regulating resistor so it outputs ~50mA instead of 1A.

Nice. These mc1 are really cheap and slide very nice, I also have one bought for few dollars in one of the last sales. How does the stock circuit board look like?
And how did you open the mc1?
I haven’t seen the two parallel modules but I have thought about it too.
You could also use a potentiometer to adjust the current, just replace the stock current selecting resistor with a pot and you would be able to charge even small batteries…

Sorry I didn’t really look at the MC1 circuit before I stripped it all off and soldered my wires on. The MC1 is just glued around the seam; I used a razor and started at the microusb port and slowly worked my way around.

I thought about having a way to charge at a lower rate, but I really don’t use anything smaller than a 14500. I have single 10440 that I rarely use, so my VP2 will be fine for that. Mainly I wanted something faster than the VP2 for big 18650’s, and more portable. Then halfway through the project I decided to use the little omten to disable one of the chargers for 14500 duty. I’m starting to use my TG06 and L1A more than anything.

This is what I want to see on BLF all the time, thanks for sharing, great build!!

Group buy!

Sweet!!! That is very cool indeed.

Very nice work there. Congrats

Now… If just my phone hadn’t a 4.35V battery I would use it to charge the spare ones

Also, would this work with a variable resistor? Or has the resistance to be fixed at the datasheet’s values?

Nice charger on Steroids :bigsmile: the TP4056 is my favourite small charger board for Li-Ion cells. The smallest one i built was this one: Wallet-sized LiIon Charger build for pennies!

Is 1A not too much for a 14500?
I use the mc1 stock with 500mA for my efest imr16340 and I thought it is to much?
That’s why I wanted to use a charger board with pot….?
I wasn’t sure how to select the current until I have seen your post and the idea with the build in USB power meter.

I just checked a fishermans friend tin box and it is a bit too small to fit well…

Well all of the TP4056 boards that I have topped out at 0.9amp instead of the full 1amp. The recommended charge rate for my 14500’s is 0.8amp, so it’s a little high still. I’ll probably lose some charge cycles I guess. Some 14500’s even state they can take a full 1amp.

Those efest 16340’s have a recommended rate of 0.5amp, so you’re fine with the MC1 I think. I could always have swapped the resistor on one of my boards to tune it down a tiny bit, but I’m not too worried about 0.1amp.

I just opened mine, I just slipped one or two times and after cutting half the seam it popped and I could crack the rest open very easyly.
I will mod my charger just with a pot. It seems to use two 4057 giving 250mA each in stock so it could also be modded to 1A just by swapping two resistors.

I have plenty of time as I usually Play around some hours before sleeping and so I can recharge my edc 18350 a couple of hours with no problem with 0.5C.

I usually charge my 18650 with less than 1A and my smaller batteries with 300mA.

Could one of the 4057's be removed to halve the charge current to 250 mA?

Yes. Or just one of the resistors. I will make a mc1 mod thread in a few minutes….

Thanks.

Nice PD68!

What did you want to add? If you mentioned it, I missed it somehow.

Also, the KEWEISI USB meter, how low can the voltage go and have it still work, give accurate readings?

One thing I thought about adding was a powerbank controller and full USB out, but I would’ve had to use a bigger tin. The other thing was a second omten switch just before the MC1. That way I could store a cell in the holder with it completely locked out for travel. You can actually see the white omten in the wiring picture, but I had to take it out. It wasn’t secure and the wire didn’t fold correctly with the hinge. Instead I just store a small piece of un-shrunk shrink tubing that I can slip over the slider to isolate it from the battery if I ever want to travel with “one in the chamber”.

The way I tested the meter was to check a cell with my DMM then put it in the charger to see what it read. I also poked the ‘out’ pads of the chargers with my DMM while it was running. Both showed it was accurate. Because of those methods, I never tested very low of voltages. It is rated down to 3v though.

Applauds pilotdog68 , i love those DIY customs stuff of yours indeed

O.T

May i give you an idea for your next project? An Iphone 6S DIY charger 500mA: this way youll prolly get 1-10 mill in a day or two cause there are too many Apple fans PLUS you can immeadiately start at least 20 court cases vs all charger producers for stealing an Apple innovation: as we all know its the Apple who indented the first charger 350 years ago :wink: