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DIY 18650 20 bay Arduino managed Charger
#21
Thank you very much Wolf..

The earlier I learn the less time I spend doing the wrong thing.
One item of note is your methodology of treating the hibernating cells. I think your term Hibernating is the closest to what is accurate.
Correct me anyone if this point of view is wrong. 99% of commercially produced battery chargers are targeted to the end user that wishes to re-charge his/her new batteries for their Drone, Camera, Skateboard and other equipment. They were not really built for us scavengers.

That is obvious in the fact that they will not adjust to a nice low 50ma current, or even recognize a cell under 2v ish. The LittoKala I have can only be set to a min of 300mw
As I said my 3 Sanyo turned into heaters @ 500mw.. Further proof that building a "Reconditioning Unit" over a bought charger is the smart thing to do.

Now you have me convinced that having these extra 2 bays that can be programmed with specific CV/CC over the standard TP4056 units is a damn good idea.As construction has not quite started I may up the ante from 2 specialist bays to 6 now.

Cheers.. Mike
100kwh-hunter likes this post
YOLO is wrong, You live every day. You only Die once so it should be YODO. Angel
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#22
Bag of HW586's arrived this morning.. another step closed to assembly stage....

Am thinking of adding another Arduino to look after the 6 hibernation cell bays. I dont feel comfortable leaving cells online with nothing to monitor the charge if I get busy or called away.. what do you guys think?
YOLO is wrong, You live every day. You only Die once so it should be YODO. Angel
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#23
My experience with using hw586 is not great so far.
The one I tested overead the capacity (it gave figures much higer than a new cell ever had) and was inconsistent from one test to the next.
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#24
(03-11-2019, 02:22 AM)Gremlin Wrote: Bag of HW586's arrived this morning.. another step closed to assembly stage....

Am thinking of adding another Arduino to look after the 6 hibernation cell bays. I dont feel comfortable leaving cells online with nothing to monitor the charge if I get busy or called away.. what do you guys think?
Gremlin,

When I put 20 cells in parallel on my 20p recovery (hibernation wake up) board I am charging at 50mA per cell. I do check IR initially to see if there is a very hi IR cell and those don't make it initially. The highest °C I have ever seen a cell get is ~25°C that is with the others at ambient 19°C. So as far as leaving cells unattended it is never a good idea with unknown cells. I personally have a pretty good feel now at what will be a "Heater" or not so I do leave the 20p unattended. At 50mA I personally don't see a lot of harm can come of it. Thats what I do. Even if 1 cell where to be a "VAMP" cell and use all of the 1A charge current (highly unlikely) it still wouldn't cause a meltdown. That is the advantage of doing the parallel charging method. Single cell charger boards, those can be a bit more difficult. Like the TP4056 board will charge at 1A unless you change a resistor on them to throttle them down. I have a 40 slot unit that I built with that chip and use that on >3V cells. For the <3V cells the CC/CV boards and holders are not that expensive to build a parallel charger so that would be my suggestion. The Arduino idea I like let me know how you make out.

Wolf
If 18 X 650 = 2200+mAh then we have power! 
May all your Cells have an IR of 75mΩ or less Smile
Last count as of 8/7/2019
Total Number of Cells Recorded and processed                 6149
Total Cells required for PowIRwall                                   2856
Total Cells ≥2200mAh, ≥80%, ≥35mΩ, ≤75mΩ, ≥4.12V   2760
For Info Google Drive
Not your average Wolf       
            Cool
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#25
Sure I will let you know, thats what its all about, helping each other is it not.

Now today I spent some time with a knowledgeable fella, with his guidance and a few handful's of old laptop chargers (the internal ones in the packs). He walked me through a circuit that will allow me to use the temp sensors from them in the 6 slot area of the unit I am making.
Using the second Arduino I have been shown how I can monitor the unknown cells for temp, so even if I walk away the cell will be isolated once a yet to be determined temp threshold is exceeded. Is it necessary, no. Is it nice to have? Definitely!. Considering the cost to include this in the 6 bay special area is less than a dollar, why the hell would one not do this?
I may even up-grade the normal 20 slots at some time in the future. I have tested a handful of the free thermistors today and selected 8 (2 spares) that checked out withing single digit ohms of each other.
A swift google search pointed me to a 10K resistor being the correct partner for the voltage divider at 5v supplay and viola! instant accurate temp sensor for the ugly cells section.

So for those reading that do not have temp sensors, and you strip laptop packs, Know now that you are throwing one or two free ones away with every case you strip out

Cheers for now.. Mike
Wolf likes this post
YOLO is wrong, You live every day. You only Die once so it should be YODO. Angel
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#26
Stripping cell packs has resulted of me probably having over 600 Temp sensors. LOL
I strip all the electronics and nickle strips and sort them accordingly to make it easier to recycle.
Same with the plastic most of the cases are recyclable.

Wolf
If 18 X 650 = 2200+mAh then we have power! 
May all your Cells have an IR of 75mΩ or less Smile
Last count as of 8/7/2019
Total Number of Cells Recorded and processed                 6149
Total Cells required for PowIRwall                                   2856
Total Cells ≥2200mAh, ≥80%, ≥35mΩ, ≤75mΩ, ≥4.12V   2760
For Info Google Drive
Not your average Wolf       
            Cool
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#27
Hokay, more stuff has arrived, still not got all that I ordered as yet though.

Thats the biggest hold up, you order something from China, they run around for a week, then pack the stuff, give it to a one legged rickshaw driver . He runs across the country with it, delivers it to the guy at the docks. He jumps in the water and swims to a freighter anchored off shore, they take it on board, set the sails and paddle to Australia with it.

If china ever fires a missile at anyone, you can expect a 40-65 day delivery.

end_rant/

Sigh..
Have a great day people.
Grumplestiltskin, Geek, Korishan And 1 others like this post
YOLO is wrong, You live every day. You only Die once so it should be YODO. Angel
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#28
(03-18-2019, 07:58 AM)Gremlin Wrote: Hokay, more stuff has arrived, still not got all that I ordered as yet though.

Thats the biggest hold up, you order something from China, they run around for a week, then pack the stuff, give it to a one legged rickshaw driver . He runs across the country with it, delivers it to the guy at the docks. He jumps in the water and swims to a freighter anchored off shore, they take it on board, set the sails and paddle to Australia with it.

If china ever fires a missile at anyone, you can expect a 40-65 day delivery.

end_rant/

Sigh..
Have a great day people.

Then it shows up a counterfeit item!

So if China fires a missile at anyone, it will take 45-65 days to reach its destination, and it will be full of sand!
Gummiadler and Grumplestiltskin like this post
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#29
Progress update:

All cell holders are mounted, All the Reverse polarity circuits are built on strip board and fitted into 3D printed trays to make them a bit neater.
The INA219's are still lost in the void known as China postage, however the trays to hold them in groups of four are now being layered up in the printer.

The second buck converter to run power to the relays has arrived, and the second batch of 10 HW586's has been ordered.

A question, actually two.

Do the HW586 retain the setting between battery swaps? EG do you need to program the cutoff point every time you swap out a cell?.
And the second question. Is it possible to get an Arduino to press the "go" button?

The reason I ask this is I would like to set up my unit to cycle charges. Again, EG slot a cell in, set the GUI to 3. and the unit runs a charge discharge cycle 3 times.
The OK button seems to only monetarily bridge a simple circuit to ground.

This of course is useless to me if the lower cut off point needs to be reprogrammed on each cell change.

Mike.
YOLO is wrong, You live every day. You only Die once so it should be YODO. Angel
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#30
If no one else posts before, I will try to look at this for you tonight (Sydney time).
.
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