Hacking a TP4056 charger module

R

Rad

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I have a bunch of TP4056 modules in my mass charger. I have noticed they charge to about 4.22 volts, range is 4.20 to 4.25 volts. This is quite a bithigher than I would like. Is there any way of reducing the charge voltage to say 4.05volts? It would be great to have one common reference voltage fed to all the TP4056 modules so they all charge to exactly the same voltage. Has any clever electronics person experimented with this?
 
It looks like TP4056 chip has fixed voltages built in & no options for changing, eg a resistor value.
You could put a schottky diode in series with the +B lead & get a drop of ~0.3V but it increases losses when charging.
 
Nope, voltage is an issue. schottky diode is probably the easiest and cheapest way of doing it. Altho, I think the diode would keep the TP from properly monitoring the cell, as well. Afterall, diodes only allow voltage in direction. So wouldn't the TP not see the voltage of the cell and either 'not' charge at all (thinking there is no cell) or still overcharge?
Perhaps putting a diode in both directions?

I'm not sure on that part as I haven't messed with them to that point. Just thinking outloud and trying to get clarification before you solder up a bunch of TP's for naught ;)
 
In my tampering with the 4056's ive learned that even placing an ammeter in series with the output affects the charging cycle in a decent way, which is probably why they recommend doing in on the input (I was doing wrong for ages!)
Regarding diodes, i dont know about that kinda thingbut my answer to everything is to MCU everything :p

Maybe have a Nano with a couple of additional ADC devices like the MCP3008 and some IO expander devices like the MCP23S17so you can measure the cell voltages during charge anddisable the chargers as they hit a certain voltage.
Thought the cells seem to settle downby about 0.15v after wards so maybe a limit of 4.20v to stop the cells continuing with constant voltage phase. May just give you the result you want. Its what i do anyway

How many TP4056 modules do you have in this mass charger?
 
Not a bad idea modding the charger and adding intelligence to it. It has 30 modules so would need at least 30 ADC input channels and 30 IO lines. I am in the process of building a 30 bay mass discharger, it could also do with some MCU.


image_xbdjil.jpg
 
Rad said:
Not a bad idea modding the charger and adding intelligence to it. It has 30 modules so would need at least 30 ADC input channels and 30 IO lines. I am in the process of building a 30 bay mass discharger, it could also do with some MCU.


image_xbdjil.jpg
Click to expand...

Very nice ;)I love a tidy job
In that case you'd need x3 MCP3008's (each give 8 analog inputs via SPI), x2 MCP23S17's (each gives 16 I/O's via SPI)
And that'll leave x10 digital I/O pinsspare and x2 analog inputs spare

There may be bigger expanders out therebut these are the only ones I've used.
The serial log can be sooo handy. If you wanted to log charging current though you'd need another x4 MCP3008's on top of it all :p
You may havea lot of wiring ahead of you if you choose this path!
 
Unfortunately TP4056 doesn't have an external reference input and the internal is fix 1.22V
Just add a resistor in series with the battery. The voltage gonna drop and you can change it with the resistor value. For example: a 0R05 resistor gives you -0.05V
Cutting the battery before reach a certain voltage(<4.2) is not recommended, it's gonna miss the CV stage!

Best option: use a different charger IC which perfect for your needs.
Best option2: Check your TP modules and use the good ones. You can measure the Voc without battery, that's a good indication.

BTW I'm not surprised on the voltage swing what you experienced, a lot of TP clones out there.
 
Thanks for the suggestions, yes it would add a fair bit of wiring, if I used thinribbon cable it could be quite neat though. I should have done the mods right in the beginning, I have now chargedabout 1900 cells out of 2600 so will soon start discharge testing soon.
 
FERCSA said:
Unfortunately TP4056 doesn't have an external reference input and the internal is fix 1.22V
Just add a resistor in series with the battery. The voltage gonna drop and you can change it with the resistor value. For example: a 0R05 resistor gives you -0.05V
Cutting the battery before reach a certain voltage(<4.2) is not recommended, it's gonna miss the CV stage!

Best option: use a different charger IC which perfect for your needs.
Best option2: Check your TP modules and use the good ones. You can measure the Voc without battery, that's a good indication.

BTW I'm not surprised on the voltage swing what you experienced, a lot of TP clones out there
Click to expand...
The 'hidden' reference voltage is a great pity, I think your option 2 would be great. Just buy heaps of them and test and sort them!
 
You could also take one TP board, put it in a test bench. Have the IC removed and the pads cleaned. Then buy a batch of 100pcs TP4056 SOP-8 ICs and place them on the pcb and press them firmly and do a test. These are supposedly genuine TP ic's. The logo is at least correct in the picture.

Then you could just replace all the boards you have with these ICs instead of buying a bunch of "expensive" (relative to this ICs) and tossing out the ones that are out of spec.
A good way to replace smd components is to use a flat cooking pan (one you wouldn't use for cooking afterwards), place the pcbs in the pan and heat it on the stove to 300C. This would give even heating across the whole pcb at a gradual increase in temps so the components won't get temp shocked or uneven heating. Then pull the old ICs off, drop the news on, and then move the pcb to a warm plate of around 150C to allow them cool down slowly for about 10mins, then remove them from the heat to finish cooling.
 
I did the same thing Korishan suggests. I use ebay for everything and i got 40 of theseTP4056's. I specifically asked the seller before purchase if they looked exactly the same as the picture and had the logo. Theystraight up lied to me. The "4056E" IC's that he sold me are just as dodgy as the "TC4056A" IC's they replaced.Id love to learn of reputable sellers that dont sell them for 1.50 each!
 
That's when you use the emails against them and hit them with ebay violation rule book. I've done it before and won't hesitate to fire the volley of ammo again.

It is frustrating that when you think you finally got the right part, order it, once it gets there and is inspected isn't what it was supposed to be. Parts like that, when getting the packages and you need very specific parts, only open them in front of a camera so you have video proof you didn't swap the parts.
 
StephenRyan said:
I did the same thing Korishan suggests. I use ebay for everything and i got 40 of theseTP4056's. I specifically asked the seller before purchase if they looked exactly the same as the picture and had the logo. Theystraight up lied to me. The "4056E" IC's that he sold me are just as dodgy as the "TC4056A" IC's they replaced.Id love to learn of reputable sellers that dont sell them for 1.50 each!
Click to expand...

Thanks Stephen I just had a close look at my TP4056 modules, the chip itself is marked TC4056A just like you found on yours. I wonder who the original manufacturer of the TP4056's chipsare.So....


The TP4056 charge voltage is not consistent and varies between 4.20 and 4.25, may be addressed by preselecting modules before building the charger.
The TP4056charge voltage is too high for what I would like,itcant be easily adjusted.

on the positive side:

I built a 30 bay charger for less than $30.
It has been very effective in getting through a lot of cells really fast.
 
Rad said:
Thanks Stephen I just had a close look at my TP4056 modules, the chip itself is marked TC4056A just like you found on yours. I wonder who the original manufacturer of the TP4056's chipsare.So....
Click to expand...

From what i can remember from thisforum,the genuine manufacturer of the TP4056 is Nanjing Top Power & the TC4056A's are clones made by Shenzhen Fuman. Still...as you said, 30 chargers for 30 quid. Cant complain too much ;)
 
thanks for posting this as mine were undervoltage. I will see what i have when i get home. I have about 20 to 30 more that are not inuse.
 
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