Opus battery tester charging rate?


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Hookie

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May 29, 2017
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4
Hi Guys,

I've been reading this post with interest, because I have 3000 batteries to process. Currently I'm using four Foxnovo 4S chargers to discharge/charge sixteen batteries concurrently. Given it's taking twelve hours to complete, I'll be here nearly one hundred days!

May I ask, has anyone found a much faster method? I'm thinking choices are either buy more Foxnovo chargers or find another method. I have IMAX chargers, but don't know how to set up nor the pro's and con's.

Can someone please advise.

Many thanks.

Neil
 

The-J-Man

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May 2, 2017
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260
Scepterr said:
Next set of cells, these numbers don't jive
Over an hour at 1A, only about 600mah pulled?

Ok...wtf, it seems stop discharging for some period of time and starts again, it's barely warm

At 2 hours, it's at 1000mah pulled, so it seems to avg 500mahdischarge even at 1000 setting? Is mine broken or is this how it's supposed to behave? With the 4S I would see 1000mah pulled at the 1 hour mark

Im pretty sure you have a broken unit.

Im using 3 of them and they are doing just fine. Takes about 2h - 2h 30minto discharge my 2200mAh hoverboard cells and they show capacites of 2150-2350mAh. These are inflated numbers buts thats well known for the opus (10-15%)

The units have big variences in accuracy though. I have gone through 5 units to have 3 that are as accurate as possible. My first one is a bit high in measured voltage, so a full cells of 4.2 is displayed as 4.22-4.23. The other 2 units I have are nearly spot on.

I also have 2 foxnovo 4s units that I am only using to charge the cells as its quicker to pop the cells in and start the charging process.

With this setup im knocking out 12 cells every 2.5hrs max. (my cells are mainly all the same) at the moment.

The thing with the unit stopping discharging is because of heat. It has temp sensors for the cells and if they get too hot during discharge it will stop the process and then continue it after its cooled down.
Is the cooling fan running normally?
To stop the units from pausing the process I have a USB fan blowing over the chargers and I have my units placed on a notebook cooler, gives it a nice angle and blows some cooler air into the bottom vents of the units. The fan keeps the cells a bit cooler and they discharge without stopping.

image_spyzmg.jpg
 

Scepterr

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Feb 19, 2017
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J-Man I'm guessing mine was broken, it never got hot hardly even warm, I sent it back. If you wanna speed up the initial charge I would suggest leaving the pairs of cells together, I've gone through 400 like that, the last 200 I got I charged the packs directly through the bms
 

The-J-Man

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May 2, 2017
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260
Scepterr said:
J-Man I'm guessing mine was broken, it never got hot hardly even warm, I sent it back. If you wanna speed up the initial charge I would suggest leaving the pairs of cells together, I've gone through 400 like that, the last 200 I got I charged the packs directly through the bms

I did that with the first 5 packs I disassembled. These were over discharged to between 8 and 18V. I took them apart and separated them into pairs, revived one pair at a time with my iMax and then placed them into the 4s. I saved time overnight obviously as it charged double the amount of cells.
However,I found that taking them apart, carefully cutting the nickel strip without damaging the cell wrap, thenputting them in the charger in pairs, charging them and then taking them apart before discharge took me longer then just stripping them apart completely and doing it singly. I also clean my cells from the glue residue at disassembly.
But that was only my observation of course.
I also label my cells by pack, I was not always able to write the pack number on each cell when in pairs depending on how they are rotated. After taking them apart I would have to then think about labelling some again.I currentlyhave 80 of the hoverboard packs, and im up to pack 45 in testing now. Barely did any testing these last two weeks, otherwise I would be done by now.
My idea behind labeling them by pack number is that those 20 cells will be close to identical condition. I am then grouping the cells together in my build. If in the future 1 or more cells from a certain pack of 20 fails its easy to replace other cells from the same pack of 20 if they too are about to fail. If I bunch them all up and then put them together I might end up having 1 cell in each of my 14 final packs fail (if that original hoverbaord pack had problems) resulting in a lot of maintenance work.
 

Joost2

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Jun 21, 2017
Messages
117
I have no problems at all.

My 8 opus chargers are mounted at a wooden wall and cutoff the original adaptors. The opus are connected too a 750W power supply. I'm cooling it with a 12cm computer fan. I made from cardboard a tunnel too forces the cool air cool al the opus. Not one battery gets hot.

The only problem I have is that not ever battery will charged at 4.2v but 4.15/8v. Too solves this I took them out notes the capacity on the battery and put them back too charge at 300mah. After it shows full I put them out and let them rest for one day and measure the voltage.
 

daromer

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Oct 8, 2016
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5,662
Its just one problem when you cool the cells. Will you have the same type of colling on the wall?
If not i do suggest that you dont cool them for the testing phase it self. Because you would want to know what cells that do get warm.

On the other hand the capacity may differ and if so perhaps run 2 tests. 1 with cooling and 1 without.
 

Joost2

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Jun 21, 2017
Messages
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X Got the cells heating from internal resistance or discharging?

I have no heating camera so how can I judge it right....?


Normally when you discharge the pack you have only the internal resistance that creates heat and not a big resistor like at the back of the opus. I try too charge two cells and two cells discharge at the same time too avoid heating.

I trust my alc 8500 experts battery stations internal resistance results instead of the opus. With my alc experts I can messure the internal resistances at different load test, like 1A too 10A.

What are yourinternal resistance?
 

Korishan

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You don't need a thermal camera to know if a cell is to hot. If you can't put the back of your hand/fingers on the cells for longer than a second, it's way to hot. The other thing would be to get a thermal gun w/o the camera portion. They cost less than $20USD. You just need to make sure you take a reading really close, as in touching the cells to get accurate readings since the cells are so close.
For the thermal reading, 125F (50C) is about as hot as you wanna go on cell temps. Hotter than that they are getting into the danger zone for the type of work we do.


As a bugging, for my brain keeps goin nuts when I see it. 99% of the time you use "too" instead of "to". My brain keeps tryin to put "also" meaning to the word "too" :p
 

daromer

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On discharge the internal resistance can create heat but I dont think thats the big issue compare to the heat from the charger itself. So cooling on discharge may be totally fine. But on charge on the other hand I have only seen the cells heat up. But they also generally end up with very low capacity or a very very long charging time :)
 

Chiptosser

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Jul 2, 2017
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After reading through this tread twice, I still do not know which 4s charger is being referenced. Some clarification, Please!
 

Korishan

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The Opus charger was mentioned multiple times. But also Foxnovo is talked about with similarities.
 

Chiptosser

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Jul 2, 2017
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Yes, but the sound of the conversation: ( I would charge at the lower rate initially. but I do the discharge testing at 1000 ma setting on the digital charger 4s, which is similar to the opus)
I don't know how you guys copy other peoples posts over.

Sounded like another unit was being referred to too. Because, I have a, digicharge 4s, charger, but it does not have discharge ability.

I wanted to make sure , Is there a list of charger- discharger units on the market?
 

TheBatteries

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Chiptosser said:
Sounded like another unit was being referred to too. Because, I have a, digicharge 4s, charger, but it does not have discharge ability.

The "Digital Charger 4s" is different than the "Digi Charger 4s". This is the Digital Charger 4s (by Foxnovo) that most people are using.
http://www.ebay.com/itm/151833464430
 
Joined
Jul 22, 2017
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So far I'm not worried about dealing with 100's of cells a day, so my system may not be that efficient. However, it is fairly simple to expand.

I use this charger (a Hitech RC charger) http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXGHSD&P=0 for charging and resistance testing. I took 4 of the 4 cell holders and soldered them in parallel so I can charge 16p at 6 amps. Yes, I know that is a slow charge, but it works for me for now. If you have several Imax b6 chargers, I imagine you could do the same charging setup. It isn't as fast as having 4 different chargers doing 4 cells each, but takes much less space, and I don't have the problem of 100's of cells to test every day. If anyone wants to help me change that....I'm game ;-)

I then use multiple ZB2L3 resistor based capacity testers to check capacity at 500 mA drain. I am in the process of building out a discharging board/station that will have 16 of these on it. Since I only drain to 3v, they take about 2.5-4 hours depending on battery capacity.

Eric
 
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