Tutorial: how to use opus bt-c3100 to test capacity of prismatic liion batteries capacity

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USSR
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Tutorial: how to use opus bt-c3100 to test capacity of prismatic liion batteries capacity

 

  Hi,

I wanted to test the capacity of various mobile phone batteries to assess their realy vs stated capacity.

since opus accepts only cylinderical ones so i got an an idea to use my dead universal mobile phone battery charger as a holder for opus. i removed the circuit . soldered a nice wire from another charger (2 amps ) its hardly 5-6 inches pure copper wire. labeled  the positive terminal on the case . put some insulation on the soldering points and inserted a foam in the empty shell to give it fuller feel and press the wires to avoid them coming off or shorting togher.. 

as a first hastly trial i just insulated an 18650 dead cell and placed the wires with appropriate polarity against he cell in opus and started charging ..

TESTS:

1: Nokia BL-5CB 800mah  battery after 2 yeaqrs of use had 763 maH capacity.

2: A chinese BL-5C stating to be 1070mAH supposidely high quality ( Tely brand )   battery turns out to be 750mAh

3: Two other chinese after market supposidely 1200mah high qulaity batteries for samsung s5570 were tested one was 750mAH other 570maH.

 

 

 

 

here are pics ..

  http://imgur.com/a/a1762

 BUT THERE IS A CAVIATE tO IT. AVOID Shorting the battery .. later i will find some plastic to permantely hold the terminals for opus.

 

 

 

 

 

 

 

 

Edited by: USSR on 09/07/2015 - 06:27
tempo
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can you share the discharge graph of your phone battery?

USSR
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opus doesnt supports graph.

however opus sucks fixed constant current till battery reaches 3 volts.. so its graph is a rectangle and its area is the battery capacity .( mA x time in hours ) .. this is valid for discharge graph. 

 

 

tempo wrote:

can you share the discharge graph of your phone battery?

 

 

 

tempo
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this method works but there is nothing exemplary about it

you're pressing the bare wire against the Opus metal contacts to make electrical connection

i am sure that there are more elegant ways to connect black/red wires to the battery tray

flydiver
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I absolutely applaud this method! There are almost NO reviews of cellphone or digital camera batteries that have any objective data associated with it. 90%+ of the reviews on these things are mostly useless. People simply have no data. They either think they are fine or they are crap. What I’ve found it mostly they are modestly poor to miserable….so far.

I do a similar thing using an Accucell-6 (hobby charger), and a Universal battery charger.

I loop a couple small wires around the contacts, (contacts are adjustable to fit various batteries), run them to the charger, and I can do charge/discharge tests with pretty good accuracy, more than the Opus.

FWIW I’ve found that MOST aftermarket cellphone and camera batteries are seldom better than 50-75% of claimed capacity. Like Ultrafire, the higher the claim, the worse the battery. I did a minor test ordering only batteries that claimed no more than stock, and even a bit less in one case. They weren’t as terrible but neither were they up to spec.

To Air is Human, to Respire….Divine.

USSR
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tempo wrote:

this method works but there is nothing exemplary about it

you're pressing the bare wire against the Opus metal contacts to make electrical connection

i am sure that there are more elegant ways to connect black/red wires to the battery tray

yes this is pretty crude setup. it can definitely be improved. it was just first prototype.

 

gauss163 wrote:
What rate (current) did you test at? It is possible that cellphone batteries are rated at less than C/5 rate because they drain at much lower rates in phones. If so, you'd need to test at that lower rate to reproduce the nominal capacity rating.

 

 

they were tested at 300ma .. thre is slight difference if they are tested at 700ma.. hardly 40-60mah at most. 

 

 

 

dchomak
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This is a clever way to charge and test cells from devices that don’t use cells that the OPUS was designed for.
I say clever because I have been doing this too Smile

I would like to point out that when it comes to our flashlight cells, many of us have become anal about them. The most important cell we own and probably the one we use the most and recharge everyday is the cell in our cellphone. Yet how many of us know the charging current, the mAh capacity or the cutoff voltage?
How many have even wondered what they are?

snakebite
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check out the maha 777+2.might be hard to come by now.even a junker is nice to use for the base hooked up to a hobby charger.
i noticed the whateverfire effect on aftermarket phone packs long ago.
new oem packs always test slightly over the rated capacity.
easiest way to catch the lies is to measure the pack and see what the top capacity from a reputable brand of cell is.
then you can safely assume that whoflungdung pack that claims twice that capacity in the same size is BS!

flydiver
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Quote:
Normally Li-ion is rated at C/5, which for 800mAh would be 160mA. But I wouldn’t be surprised if cellphone batteries are rated at much lower rates typically used in a cellphone, e.g. C/20 (here 40mA) since this better reflects real-world usage, i.e. batteries last more than 5hrs, even more than 20hrs in typical cellphone usage.

I agree with this in principal. It can be difficult to do that without having some more elaborate technical equipment. The lowest my hobby charger can go is 100mA. For my cellphone rated at 2100mAh I used 200mA, and 100mA for the smaller stuff. I want to know if the cell is somewhere in the range specified or if it’s complete hype. It also gives you ammunition to go back to the seller with data and photos. I went through 4 poor fake Samsung batteries and finally the eBay seller just gave me a refund. Took me another month to find an authentic RayOVac on eBay for a reasonable price. That one is working out fine.

To Air is Human, to Respire….Divine.

USSR
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they were not much variation in readings ( charging/discharging at 700ma vs 300ma ) as per my tests.

also as shown in first post i tested a genuine bl-5cb which nokia rates as 800mAh battery.. at 500mA and at 300ma there were only slight differneces in capacity..

most phones from 2012 using high capacity batteries use 1A or 2 A chargers

 

 

flydiver wrote:
Quote:
Normally Li-ion is rated at C/5, which for 800mAh would be 160mA. But I wouldn't be surprised if cellphone batteries are rated at much lower rates typically used in a cellphone, e.g. C/20 (here 40mA) since this better reflects real-world usage, i.e. batteries last more than 5hrs, even more than 20hrs in typical cellphone usage.
I agree with this in principal. It can be difficult to do that without having some more elaborate technical equipment. The lowest my hobby charger can go is 100mA. For my cellphone rated at 2100mAh I used 200mA, and 100mA for the smaller stuff. I want to know if the cell is somewhere in the range specified or if it's complete hype. It also gives you ammunition to go back to the seller with data and photos. I went through 4 poor fake Samsung batteries and finally the eBay seller just gave me a refund. Took me another month to find an authentic RayOVac on eBay for a reasonable price. That one is working out fine.

 

 

 

ChibiM
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it smells like squirrels here.



chargers and squirrels go hand in hand

USSR
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ChibiM wrote:

it smells like squirrels here.

hargers and squirrels go hand in handTongue Out

can you check by changing your place ? but  all species have a characteristic smell and they have to live with it. 

:Davie

 

 

 

 

 

will34
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I have a similar setup, but for charging phone batteries. It uses a Xtar MC1 Plus and a USB power meter to measure real time voltage/current/capacity.

ReManG
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will34 wrote:
I have a similar setup, but for charging phone batteries. It uses a Xtar MC1 Plus and a USB power meter to measure real time voltage/current/capacity.

Now that is slick! This place has so many different ways to do things, part of the reason I love this forum….