Opus BT-C3100 Questions for a newbie

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Yourrid
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Opus BT-C3100 Questions for a newbie

So I went out and bought the new Opus BT-C3100 charger in hopes it will have all the functions I may need as time goes on. But I have a few questions regarding charging and discharging batteries.

I have 4 batteries so far (2 18650 unprotected, 1 26650 unprotected, 1 CR135A store bought Panasonic)

I really want to put the charger through it’s paces but I don’t want to damage the batteries. So here come the questions…

1) What is a good charge rate? Apparently this thing will charge from 200 to 2000 mA’s so I don’t want to burn them up

2) What is a good discharge rate? Is slower better than faster?

3) With the batteries being unprotected, should I worry about the charger killing my batteries or are there safeguards?

I want to use the charge/refresh mode and the above questions directly relate to me using that mode.

Thanks for any info!

dekelsey61
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Good charge or discharge rate is 1A or 1000ma.

Le_Zouave
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The good charge rate is 0.5C, which mean half of the rated capacity.
So let’s assume than your cells are rated more than 2000mAh, charging at 1000mA is good.
They certainly can stand 2000mA charging intensity but better be safe.

200mA is what you’ll use to charge AAA NiMH (even 300mA will do safely)

1/ 0.5C
2/ 0.5C, less intensity is better for battery life
3/ refresh mode is for NiMH, Li-ion don’t really need refreshing (I want to shout really loud when common people want to discharge their cellphone until it shutdown itself before charging)
There is safeguard in this charger, it won’t discharge too low (which will simply kill the li-ion). If the voltage is so low that it’s recognized as NiMH (below 1.5V), the li-ion battery is already dead. It only lack a thermal sensor on the battery (there is a thermal sensor on the charger, if the fan don’t work for example).

Yourrid
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Great info Le_Zouave, I’m still learning so I’m trying not to fry TOO many batteries.

Here is another question about the charger.
CR123A 3V battery seems to get really hot and never finishes charging (my 2900mAh 18650’s charge to full and the cr123a still says charging. It charges it up to about 3.45 volts but doesn’t seem to say “FULL” Is the charger compatible with 3v’s? I thought it was???

wight
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I never saw anything that indicated that the BT-C3100 was compatible with RCR123A's. They are RCR123A's, right?  Regular 123A cells are primary = not rechargeable.  

RCR123A cells are normally Lithium Ion cells which can/should have a diode to reduce their voltage and make them "compatible" with devices intended to run on regular 123A cells.  What we call a 16340 is similar but without the diode.  The charger does work with 16340's. 

Still fine, still on a break. One day I’ll catch up with you folks! previous wight catchup Wink
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cat eyes evil twin
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wight wrote:

I never saw anything that indicated that the BT-C3100 was compatible with RCR123A’s. They are RCR123A’s, right?  Regular 123A cells are primary = not rechargeable.  

RCR123A cells are normally Lithium Ion cells which can/should have a diode to reduce their voltage and make them “compatible” with devices intended to run on regular 123A cells.  What we call a 16340 is similar but without the diode.  The charger does work with 16340’s. 


i did not know this stuff.
so the RCR123A puts out 3V ????
how do you charge a RCR123A ?
thx
Yourrid
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wight wrote:

I never saw anything that indicated that the BT-C3100 was compatible with RCR123A’s. They are RCR123A’s, right?  Regular 123A cells are primary = not rechargeable.  

RCR123A cells are normally Lithium Ion cells which can/should have a diode to reduce their voltage and make them “compatible” with devices intended to run on regular 123A cells.  What we call a 16340 is similar but without the diode.  The charger does work with 16340’s. 

Well shiver me timbers… turns out my battery happens to be a lithium-ion CR123A NON-rechargable… who would have thought…

here is my exact battery. Didn’t know they made NON-rechargable lithium-ions. Figured they would have just made it a darn alkaline… Panasonic CR123A

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Oh wow, I’d put that cell outside ASAP! Primaries are nasty when they vent.

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Chloe wrote:
Oh wow, I’d put that cell outside ASAP! Primaries are nasty when they vent.

Like I said; trying not to fry TOO many batteries.

Looks like I’m in the market for a high capacity R CR123A 3v battery as I really don’t want to throw this one back in my $600 holographic weapon light Sad

wight
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Yourrid wrote:
Well shiver me timbers... turns out my battery happens to be a lithium-ion CR123A NON-rechargable... who would have thought... here is my exact battery. Didn't know they made NON-rechargable lithium-ions. Figured they would have just made it a darn alkaline... "Panasonic CR123A":http://www.batteryjunction.com/1pcencr3voph.html?gclid=CjgKEAjwn-WcBRD61... The correct term is "Lithium", so you could call it a lithium primary cell.  The battery you linked to is not a "Lithium Ion" cell.  Lithium primary chemistries have lots of nice things about them that Alkalines do not.  See here: http://en.wikipedia.org/wiki/Lithium_battery

"Lithium Ion" is a different thing and is a term used to describe a different family of Lithium chemistries (the rechargeable ones): http://en.wikipedia.org/wiki/Lithium-ion_battery

 

cat eyes evil twin wrote:
i did not know this stuff.

so the RCR123A puts out 3V ????

how do you charge a RCR123A ?

thx

Frankly I don't even know.  RCR123A cells are red-headed step children for a reason.  They are a bad solution to a problem that shouldn't really exist.  Critical things that expect Lithium primary cells should be fed lithium primary cells IMO.  Mission critical equipment such as firearm accessories, first responder gear, etc... if it's built for a 123A that's what I'd give it.  

On the other hand, if it's made to accept Lithium Ion cells then it can be fed the appropriate size Li-Ion like a 16340 or two, or an 18650, or whatever is called for.  

Yourrid wrote:
Like I said; trying not to fry TOO many batteries.

 

Looks like I'm in the market for a high capacity *R* CR123A 3v battery as I really don't want to throw this one back in my $600 holographic weapon light  :(

  • light or sight?  or is it both?
  • what model?
Like I said earlier, I'd just give it what it wants if it's a holographic sight.  A primary 123A should last a long time in one of those things and if that's what the manufacturer calls for...

Still fine, still on a break. One day I’ll catch up with you folks! previous wight catchup Wink
list of my drivers & variants (A17DD, FET+1 stuff, WIP stuff, etc)

Le_Zouave
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3V rechargeable kind of batteries are not compatible with this charger.
There is a switch inside (you need to open it), one for 3.7V (LiFePO4), one for 4.2V (regular li-ion) and one for 4.35V (li-on that can go up to 4.35V, mainly found in battery pull).
What he does automatically is to recognize NiMH from lithium because lithium battery that are under 2V are dead.

If you want to charge RCR123A, you need a dedicated charger.

Yourrid
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wight wrote:
light or sight?  or is it both?
  • what model?
  • Like I said earlier, I’d just give it what it wants if it’s a holographic sight.  A primary 123A should last a long time in one of those things and if that’s what the manufacturer calls for…

    Its an EOTech EXPS-3 holographic sight. After talking with you guys, I may just keep going with lithium primaries. I would really hate to fry a $600 sight because of a $5 batter. As much as I want to put my new charger to good use.

    wight
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    Yeah I took a look at the manual, I would stick with 123A. Those holographic sights get good battery life anyway right?

    Still fine, still on a break. One day I’ll catch up with you folks! previous wight catchup Wink
    list of my drivers & variants (A17DD, FET+1 stuff, WIP stuff, etc)

    Yourrid
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    wight wrote:
    Yeah I took a look at the manual, I would stick with 123A. Those holographic sights get good battery life anyway right?

    Hard to say. Unfortunately it doesnt have a low battery alert so you have no idea if it is going to work or not when you may need it most. I guess the next best thing would be getting a multi meter and check it periodically.

    wight
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    I’m not sure where they draw the line between big and little guns, I assume somewhere around 5.56 NATO and 7.62 NATO. Anyway my point is that the manual does say you should see the reticle start to blink on recoil as the battery gets low. IIRC it doesn’t mention how much of a heads up you are getting. That also doesn’t work for the “big” guns since the manual says it may blink with them anyway.

    Check section 2.1.4 of the manual (page 13). When the reticle starts blinking at power on you have between 2.5 and 5.0 hours of battery left. I’d say folks with critical applications may just replace the 123A every time they do a full teardown of the gun. With a 600hr battery life that should be enough if you do a teardown at least once a year.

    I can’t remember if you can get an accurate state of charge from a 123A while it’s “at rest” by using a multimeter. I don’t think you can. This is a tricky subject, a lot of chemistries won’t give you a reading that means much: they stay high until they are empty and then they drop like a rock.

    Still fine, still on a break. One day I’ll catch up with you folks! previous wight catchup Wink
    list of my drivers & variants (A17DD, FET+1 stuff, WIP stuff, etc)

    cat eyes evil twin
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    i used to charge rcr 123a with those cheap $2.00 chinese chargers-
    it all worked ok-
    when charging batteries, you use higher voltage current than the voltage of the battery-
    so it seems like you should be able to use the same charger to charge rcr123 as to charge 3.7v lions-
    what voltage would you use to charge a 9v alkaline cell ??

    i know it is obvious that i know nothing about this,
    but i am learning a lot by asking stupid questions

    wight
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    cat eyes evil twin wrote:
    i used to charge rcr 123a with those cheap $2.00 chinese chargers-

    it all worked ok- 
    when charging batteries, you use higher voltage current than the voltage of the battery- 
    so it seems like you should be able to use the same charger to charge rcr123 as to charge 3.7v lions-
    what voltage would you use to charge a 9v alkaline cell ??

    i know it is obvious that i know nothing about this,

    but i am learning a lot by asking stupid questions

    You DO NOT CHARGE "primary" chemistries such as Alkalines.  http://en.wikipedia.org/wiki/Primary_battery

    I'm not sure if what you were doing with the rechargeable RCR123A cells was OK or not - the $2 auto-detecting Chinese chargers are a special case.  I don't think they are recommended for anything, but I've used one before and it did function.  We've already established that I don't personally recommend RCR123A cells and I'll say that I also don't recommend the $2 universal chargers.

    Rechargeable cells intended to replace 9v alkaline cells come in a variety of chemistries, you should do some searching to bone up on this subject if rechargeable 9v batteries is what you are asking about.  NiMH units are available, LiFe units are probably available, maybe LiPo and maybe cylindrical Li-Ion.  I would stay away from the last two and also not be thrilled about the second one.  Really I'd stick with NiMH since you can't balance any of the others.  This is another scenario where I personally do not go:  If I need 9v I use a primary.  I try to avoid using 9v batteries but there is still plenty of equipment that asks for them and in that case I currently use name brand primary cells.  

    You are also confusing your terms - "you use higher voltage current than the voltage of the battery" simply does not make sense.  Current (amps) and Voltage (volts) are two different things, together they make Power (watts).  Look these things up if you need clarification, unfortunately I do not have a great tutorial to link to.  There are tons of acceptable places on the internet to learn a little though, you'll have no trouble turning one up.

    Still fine, still on a break. One day I’ll catch up with you folks! previous wight catchup Wink
    list of my drivers & variants (A17DD, FET+1 stuff, WIP stuff, etc)

    musicmagic
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    To add to the confusion, there is LiFePO4 16340 (same size as a 123 cell) which has a max charge voltage of 3.6v and a discharge voltage of 2.5v (and it behaves very differently from a normal li-ion during a discharge), and is often labeled as “123 compatible”. You would have to check your devices max voltage to see if it would work or not. If the max voltage is 3.0v, then a fully charged LiFePO4 would fry it.

    If you can’t blind them with your brilliance, baffle them with your bullcrap.

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    cat eyes evil twin
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    wight wrote:

    cat eyes evil twin wrote:
    i used to charge rcr 123a with those cheap $2.00 chinese chargers-

    it all worked ok- 
    when charging batteries, you use higher voltage current than the voltage of the battery- 
    so it seems like you should be able to use the same charger to charge rcr123 as to charge 3.7v lions-
    what voltage would you use to charge a 9v alkaline cell ??

    i know it is obvious that i know nothing about this,

    but i am learning a lot by asking stupid questions

    You DO NOT CHARGE “primary” chemistries such as Alkalines.  http://en.wikipedia.org/wiki/Primary_battery

    I’m not sure if what you were doing with the rechargeable RCR123A cells was OK or not – the $2 auto-detecting Chinese chargers are a special case.  I don’t think they are recommended for anything, but I’ve used one before and it did function.  We’ve already established that I don’t personally recommend RCR123A cells and I’ll say that I also don’t recommend the $2 universal chargers.

    Rechargeable cells intended to replace 9v alkaline cells come in a variety of chemistries, you should do some searching to bone up on this subject if rechargeable 9v batteries is what you are asking about.  NiMH units are available, LiFe units are probably available, maybe LiPo and maybe cylindrical Li-Ion.  I would stay away from the last two and also not be thrilled about the second one.  Really I’d stick with NiMH since you can’t balance any of the others.  This is another scenario where I personally do not go:  If I need 9v I use a primary.  I try to avoid using 9v batteries but there is still plenty of equipment that asks for them and in that case I currently use name brand primary cells.  

    You are also confusing your terms – “you use higher voltage current than the voltage of the battery” simply does not make sense.  Current (amps) and Voltage (volts) are two different things, together they make Power (watts).  Look these things up if you need clarification, unfortunately I do not have a great tutorial to link to.  There are tons of acceptable places on the internet to learn a little though, you’ll have no trouble turning one up.

    thanks.
    ok, i meant the voltage of the charging current has to be higher than the voltage of the cell, to charge the cell.
    and i really do recharge alkalines sometimes. it works if you are just topping them off from halfway dead. not so good if they are dead. so in an emergency, i think you could recharge an alkaline, or a button cell alkaline, from an li-ion.

    edit- i seem to remember that the last time i put an AA alkaline in a chinese charger, it made a loud POP.
    why did it do that ??

    wight
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    cat eyes evil twin wrote:
    wight wrote:

    cat eyes evil twin wrote:
    i used to charge rcr 123a with those cheap $2.00 chinese chargers-

    it all worked ok- 
    when charging batteries, you use higher voltage current than the voltage of the battery- 
    so it seems like you should be able to use the same charger to charge rcr123 as to charge 3.7v lions-
    what voltage would you use to charge a 9v alkaline cell ??

    i know it is obvious that i know nothing about this,

    but i am learning a lot by asking stupid questions

    You DO NOT CHARGE “primary” chemistries such as Alkalines.  http://en.wikipedia.org/wiki/Primary_battery

    I’m not sure if what you were doing with the rechargeable RCR123A cells was OK or not – the $2 auto-detecting Chinese chargers are a special case.  I don’t think they are recommended for anything, but I’ve used one before and it did function.  We’ve already established that I don’t personally recommend RCR123A cells and I’ll say that I also don’t recommend the $2 universal chargers.

    Rechargeable cells intended to replace 9v alkaline cells come in a variety of chemistries, you should do some searching to bone up on this subject if rechargeable 9v batteries is what you are asking about.  NiMH units are available, LiFe units are probably available, maybe LiPo and maybe cylindrical Li-Ion.  I would stay away from the last two and also not be thrilled about the second one.  Really I’d stick with NiMH since you can’t balance any of the others.  This is another scenario where I personally do not go:  If I need 9v I use a primary.  I try to avoid using 9v batteries but there is still plenty of equipment that asks for them and in that case I currently use name brand primary cells.  

    You are also confusing your terms – “you use higher voltage current than the voltage of the battery” simply does not make sense.  Current (amps) and Voltage (volts) are two different things, together they make Power (watts).  Look these things up if you need clarification, unfortunately I do not have a great tutorial to link to.  There are tons of acceptable places on the internet to learn a little though, you’ll have no trouble turning one up.

    thanks.
    ok, i meant the voltage of the charging current has to be higher than the voltage of the cell, to charge the cell.
    and i really do recharge alkalines sometimes. it works if you are just topping them off from halfway dead. not so good if they are dead. so in an emergency, i think you could recharge an alkaline, or a button cell alkaline, from an li-ion.

    edit- i seem to remember that the last time i put an AA alkaline in a chinese charger, it made a loud POP.
    why did it do that ??

    I don’t really have anything to say about charging primaries other than “don’t do it.” You could start your own thread about it. I’d recommend posting it in the Rechargeable Batteries subforum. That will get you much more exposure than posting the question(s) here.

    Still fine, still on a break. One day I’ll catch up with you folks! previous wight catchup Wink
    list of my drivers & variants (A17DD, FET+1 stuff, WIP stuff, etc)

    deckart
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    Yourrid wrote:
    Great info Le_Zouave, I’m still learning so I’m trying not to fry TOO many batteries.

    Here is another question about the charger.
    CR123A 3V battery seems to get really hot and never finishes charging (my 2900mAh 18650’s charge to full and the cr123a still says charging. It charges it up to about 3.45 volts but doesn’t seem to say “FULL” Is the charger compatible with 3v’s? I thought it was???


    If your cr123 is 3V, then 3.45V would be fully charged + a little extra.