Two TP4056 Questions

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Eric Koshinsky

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Joined
Jul 22, 2017
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75
Hey everyone,

Been a while since I've posted anything, but now I'm back with another couple of quetsions re: tp4056 chip chargers.

Question 1: Is there any way to easilyuse these to charge up to storage state (3.7v) and stop? I don't really want to add an arduino or anything...just a simple solution if possible.

Background for Question 2: I have watchedmany videos of people building charging stations using 5 - 50 of the TP4056and powering them off of a 5v power supply with positive and negative bus bars to get the power out to all the chargers. I have seen lots where the 5V power supply only puts out 5 amps but is being used for 10+ chargers. The video makers claim that the TP4056 charge at 1 amp (which they do) so now in their charging stations they have 10+ TP4056 charging at 1 amp. To me this math doesn't work.

Question 2: Am I right in thinking that if I build a charging station with 10 TP4056 powered by a 5V 5A power supply, each TP4056 will really only be charging at 500mA? If I want to have 10 TP4056 charging at a full 1A each I'd need to have a 5V 10A power supply - right?I know that I'm using rough math here since the TP4056 is only going to 4.2V there would be a little more amperage...I'm just too lazy to do the math right now.

Thanks,

Eric
 
1: No, it always goes to 4.2V

2: If the power supply limits to 5A while keeping the voltage up, then yes. If not then you will overload the power supply or the TP4056 will just shut down because the voltage will drop. Or both. For ten of these you want a 5V power supply with 10A at least, yes.
 
Q1: I would have to agree with DarkRaven. This is very difficult (I believe) to change. Maybe some kind of feedback to trick the TP4056 into thinking the voltage is higher, but then, this would change the charging curve, too.

Q2: The PSU will put out a CV/CC (on most of them, anyways). The TP4056 will use as much available Amps as it can. However, we have to also take into consideration of the charging current curve. It's not a flat line like lead acid. So, it is quite possible to have 10 units charging and they all together be pulling less than 10amps; just depends on where they are at in the charging cycle.
 
I always spec out a slightly higher Amp rating PS for the max load of tp4056's Right now I have 10 of them and 5 Zb2l3 Dischargers on a 40Amp 5V PS Max draw I have seen has been 10.5Amps
 
Thanks for the info folks. All as I expected. Good to clarify though.

Hey jdeadman.... do you have a link or name/brand for that 40A 5V power supply? Max I can find around here is 12A.

Thanks.

Eric
 
EricKoshinsky said:
Question 1: Is there any way to easilyuse these to charge up to storage state (3.7v) and stop? I don't really want to add an arduino or anything...just a simple solution if possible.
Click to expand...

I stop mine charging at 4V using aschottky diode, with a 0.2V forward voltagein series with the battery. I also added a switch across the diode so I can easily choose 4V for storage or 4.2V for testing.
It seems to confuse the TP4056 slightly in that boththe red and green leds light up sometimes when it hits 4V, but other that that it works great.
I guess a diode with a FV of 0.5V may work to get you 3.7V, but I haven't tried it.

This is my rig:
The two cells on the left arecharging to 4V as they are tested and the other two are switched for charging to 4.2 ready to go into the Opus.

image_gaztpy.jpg

image_nujwdj.jpg


I didn't need to use those huge diodes (40L15CW), but I had free access to some, so they were the right ones. :D
 
Eric Koshinsky said:
Thanks for the info folks. All as I expected. Good to clarify though.

Hey jdeadman.... do you have a link or name/brand for that 40A 5V power supply? Max I can find around here is 12A.

Thanks.

Eric
Click to expand...
Not with me but it's just a 350w computer power supply. So I get 18amps of 12v and 40amps of 5v. Max load which I would never run close to.
 
crap...I wish I new more and had more experience with this stuff. Your setup looks like a nice simple and elegant solution. My lack of knowledge/experience means I can't even think up a solution like that.

Thanks watts-on. now I just have to figure out how to build it from the pics.... (or ask nicely if you have sketch plans ;-)

Cheers.

Eric
 
I use my RC charger and LiPo storage charge to store my batteries. You can parallel batteries if you like. I have found this charger to be very accurate for a cheap unit. It is great for charging batteries, I parallel up to 8 at a time, it will charge at 6a, and discharge at 1a. It also does capacity checking and cycling. Its a great companion for my Opus. Reverse polarity protection, and even thermal protection, if you buy a temp sensor.
 
watts-on said:
EricKoshinsky said:
.... (or ask nicely if you have sketch plans ;-)
Click to expand...

Ok, since you asked nicely... :blush:


image_zrcruk.jpg
Click to expand...

This is exactly what Rudy and I were talkin about in slack channel :) Thanks for answering it!

@Eric: You might wanna double check your ratings of the PSU's you've been looking at. When advertised, the PSU's are usually rated at 12V @ X Amps. But when you look at the specs of it, the 5V rail is usually a lot higher. So the 12A one you looked at might be on the 12V rail. Check to see what the 5V rail is rated at.
 
That is what I have been doing with my hobby charger - 12 in parallel. Works fine. Problem is I have about 1200 batteries to put into storage charge and one hobby charger. I have 60 TP4056 I could possibly use to speed up the process.
 
watts-on said:
EricKoshinsky said:
Question 1: Is there any way to easilyuse these to charge up to storage state (3.7v) and stop? I don't really want to add an arduino or anything...just a simple solution if possible.
Click to expand...

I stop mine charging at 4V using aschottky diode, with a 0.2V forward voltagein series with the battery. I also added a switch across the diode so I can easily choose 4V for storage or 4.2V for testing.
It seems to confuse the TP4056 slightly in that boththe red and green leds light up sometimes when it hits 4V, but other that that it works great.
I guess a diode with a FV of 0.5V may work to get you 3.7V, but I haven't tried it.


I didn't need to use those huge diodes (40L15CW), but I had free access to some, so they were the right ones. :D
Click to expand...

Hi Watts-on, do you find the 0.2 volt drop quite consistent? Are all your charge circuits ending up accurately at 4.0 volts? Do the diodes affect the charge cut off feature?
 
Korishan, you're correct if talking about PSU's made for desktop computers (other one's too I imagine). I haven't tried using one yet for our 'non-standard' purposes. I'm not sure about the wiring in them and don't want to get myself into electrical trouble. It's probably easier than I think though.
 
EricKoshinsky said:
Korishan, you're correct if talking about PSU's made for desktop computers (other one's too I imagine). I haven't tried using one yet for our 'non-standard' purposes. I'm not sure about the wiring in them and don't want to get myself into electrical trouble. It's probably easier than I think though.
Click to expand...

That it is. Easy as. Just Google atx pinout. Don't forget you may need a 12v load. YouTube has hundreds of videos on using atx psu for bench supply
 
Basically this all depends on how old the power supply is. Newer ones usually don't need a 12V load but don't have much oomph at 5V because that is rarely needed with recent hardware. Older ones have quite chunky 5V rails (and 3.3V for that matter) because back in the days much more stuff inside a computer ran on 5V. And those old ones need any 12V load to start sometimes.
 
Geek said:
EricKoshinsky said:
Korishan, you're correct if talking about PSU's made for desktop computers (other one's too I imagine). I haven't tried using one yet for our 'non-standard' purposes. I'm not sure about the wiring in them and don't want to get myself into electrical trouble. It's probably easier than I think though.
Click to expand...

That it is. Easy as. Just Google atx pinout. Don't forget you may need a 12v load. YouTube has hundreds of videos on using atx psu for bench supply
Click to expand...

no magic, no need for pinout: black=ground, yellow=12V, red=5V, orange=3.3V. And don't forget to connect the green wire to ground in order to turn it on ;) . I recommend using a 12V load in order to stabilize the other voltages, i.e. OPUS chargers:


image_yceriw.jpg
 
Korishan said:
This is exactly what Rudy and I were talkin about in slack channel :) Thanks for answering it!
Click to expand...

I've no idea what slack channel is, but, your welcome. :)

Rad said:
Hi Watts-on, do you find the 0.2 volt drop quite consistent? Are all your charge circuits ending up accurately at 4.0 volts?
Click to expand...

I just finished storage charging half a dozen cells and the final voltages are:
4.040 4.020 4.038 4.032 4.045 4.020
So, for my purposes that is certainly close enough.

Rad said:
Do the diodes affect the charge cut off feature?
Click to expand...

I haven't done any thorough analysis of exactly whats happening. It was just a mad idea I had one day, tried it and presto.. charging stops ~4V. :cool:
 
Oooh. Thank you. This is awesome. Never thought about it.
 
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