Opus BT-C3100 v2.2 charger

[Robert B]

Thought I'd throw this out there. Anyone who's been looking at purchasing this charger, Gearbest is having a sale on them right now for the next few days.@ $33.00. Just ordered one for myself. Have heard nothing but good things about this charger.

Merry Christmas !

 

[Jon@LiionWholesale]

We just got them in too a couple weeks ago. I was wondering why were weren't selling that many! Our price is quite a bit higher, but of course we're not in china. But if you're willing to wait that's a really good deal so go for that.

I've been using them around here. It is a pretty awesome charger. Has lots of other extra capabilities like testing and discharging batteries. It's even got an internal switch that can be set to 3.7V max, 4.2V max, or 4.35V max, so I'm also using one to set batteries to 3.7V for storage.

 

[Robert B]

The sale is only going on for less than a week, then it's back up to 49. I really like the option to cycle the batteries, and the 4.35v ability. Some say it's a PITA to unscrew the bottom to get to the voltage switch, but I plan on cutting a circular hole in the bottom for quick access.

Is there an actual automatic 3.7v storage function? Or do you just run the discharge cycle and wait for them to come up to 3.7v?. An auto function like that would be friggin awesome.

 

[Jon@LiionWholesale]

It's super easy to open, it's 4 easy to get to standard small phillips screws, open it, flip switch, close it again. Took me maybe a minute tops. But if you're going to be constantly changing it I agree drilling a hole would be best. I just have some set to 3.7V and some set to 4.2.

I also wish there was a automatic storage function. It's only on the charging side though. So if it's in 3.7V mode then it takes a battery below 3.7V and charges it up to 3.7V. If it's above 3.7, then you have to do discharge first (which if you just leave it will discharge down to 2.8 or something before stopping), and once it gets below 3.7 change it to charge mode. It's really cool how all 4 are independent though, so I can discharge on some channels and charge on others.

 

[Robert B]

Someone over at candle-power-forums posted this picture. Exactly what I'm going to do for access to the switch.

 

[caman24]

quick question i heard some people complain about the fan noise. Whats your guys thoughts? is really that noisy? i am still on the fence if i should order another xstar or go with this one

 

[Robert B]

I heard in the candlepower forums that they fixed the noisy fan problem with v2.2 with a re-design. Mine should be here in a few days and will let you know.

 

[Jon@LiionWholesale]

the fan noise is honestly a little annoying, to me, when it's sitting right beside me and charging all day. It's pretty quiet so I'm not sure why it's annoying, I could see other people not being bothered at all by it. Obviously it's to be expected in any discharge tester that it will sound like this, but while it's charging it's really not necessary.

But if I have it in the room next to the one I'm in I don't even hear it, even in a quiet room. So that's generally how I use these.

 

[Robert B]

the fan noise is honestly a little annoying, to me, when it's sitting right beside me and charging all day. It's pretty quiet so I'm not sure why it's annoying, I could see other people not being bothered at all by it. Obviously it's to be expected in any discharge tester that it will sound like this, but while it's charging it's really not necessary.

But if I have it in the room next to the one I'm in I don't even hear it, even in a quiet room. So that's generally how I use these.

You have more than 1 charger going at the same time, don't you? Personally, I'm not charging batteries 12 hours a day, so not worried about it even if it is noisy.

BTW, thanks for getting my 4 LG MJ1 button-top's shipped out so quick. I have a 4000 lumen flashlight waiting for them to fully charge.

 

[Jon@LiionWholesale]

Like I said I wouldn't call it noisy, it's a small pretty quiet fan, which is why I'm not sure why it mildly annoyed me. I barely noticed it at first but around the 6 or 7 hour mark was when I started to think that I'm not so sure about how I feel about it. At the time it was just one of them. Then again I do have it on a shelf literally a foot away from my ear all day long. Will be curious to see what you think.

Glad you got your MJ1's quick . Those are a really good pack and flashlight battery. Just got the NCR18650GA added to the site today and yesterday, we'll see which one sells more.

 

[Flightmedic76]

Just got my 3400 yesterday. Seems like it is well made and very little difference from the 3100. I decided to take 3 of my 25r's and "marry" them for my RX200. I used the "discharge and refresh" mode. Unless I read it wrong it is supposed to drain and fill them 3 times. I started it around 1000 yesterday at work and at 0600 today it was still running (was just starting to drain them again). They were almost full when I started, but at almost 20 hours it seems a bit excessive. I switched it to "charge". When they were done I just yanked them. One read 2550mah, one 2475, and the third 2455. The first one is almost brand new, and the others are about 2 months old. Any ideas? Sorry, not trying to hijack the thread...

 

[Robert B]

Jon would have a better idea on cycling the batteries since I haven't received mine yet. The 3400 is the same as the 3100 v2.1. It was branded "3400" for a specific dealer.

 

[Jon@LiionWholesale]

That actually cracks me up that they had it rebranded with a higher number. Marketing at its finest. But yes it's the same 3400 vs 3100.

You should be able to change the current level using the "current" button after starting. The default is very slow like you mentioned, I think it's 200mA. You can go up to 1000mA.

 

[Flightmedic76]

The model number is higher, so it must be better lol. I've saved your site for future needs . I'll give it another whirl just out of curiosity when I'm back on shift tomorrow morning. I checked on it throughout my shift, it just seems like it had to have ran more than 3 complete cycles. I could be very wrong since I was in and out, just wondering. If it is just a matter of using a higher current are there any cons to a quicker charge rate?

 

[Robert B]

Got my Opus BT-C3100 v2.2 in. And yes, the fan is fairly noisy. It's only a 1inch diameter fan, so it's more the pitch of the noise than the loudness.

Right now, I'm discharging a couple of 18650's, and the fan stays on constantly even at the lowest discharge setting.

 

[Robert B]

Gotta say, this charger is pretty cool. Two 18650's on the left were fully discharged, and now charging them back up to 3.7v for storage. At the same time discharging two 18350's.

 

[Jon@LiionWholesale]

Agreed. It can be kinda clunky at first, the interface isn't the best, but once you get the hang of it it is a very cool little device.

 

[judo]

Can the discharge be set to a specific level or is there a default dischcharge?
if defaulted, what does it stop at?

 

[Robert B]

Agreed. It can be kinda clunky at first, the interface isn't the best, but once you get the hang of it it is a very cool little device.

It would be really cool if you could control each slot to the voltage you wanted, have a auto discharge/recharge setting. So for example, you could have 1 slot charging normally to 4.2v, 1 slot charging to 4.35v, another slot auto discharging/recharging to 3.7v for storage, and one slot refreshing/cycling a battery.
I'd pay a lot more for a charger like that.

 

[Robert B]

Can the discharge be set to a specific level or is there a default dischcharge?
if defaulted, what does it stop at?

I think the manual says 2.9volts, then it automatically starts a trickle charge as to not let the battery get any lower.

 

[Jon@LiionWholesale]

I also really wish I could set a specific discharge level, so I didn't need to do two steps, discharge, then charge to 3.7V.

 

[Robert B]

I also really wish I could set a specific discharge level, so I didn't need to do two steps, discharge, then charge to 3.7V.

The flashlight forum guys seem to know the guy who designed the opus, and updates it. Maybe we could request he build "the ultimate charger", lol

 

[Jon@LiionWholesale]

The flashlight forum guys seem to know the guy who designed the opus, and updates it. Maybe we could request he build "the ultimate charger", lol

And I could call it the BT-3,000,000,000z

 

[Robert B]

Could have him build one with all the options we are talking about. Would be cool too, the ability to daisy chain a couple more dumb 4 bay battery holders controlled by the main unit, where you could have up to 12 batteries going at once. The extra holders could be sold as add-on options.

 

[Jon@LiionWholesale]

Interesting idea. I would think the dumb battery holders would be basically the same cost as the whole charger though. You need the FETs for discharging and the power electronics for charging on each bay.

Having one that could discharge to 3.7 though, especially without having to use an internal switch, that I would pay money for.

 

[Robert B]

I don't know, I would think most all the electronics could be in the main unit, and the dumb terminals connect via cable with amphenol connectors. You wouldn't want long cables for sure. Power and signals can be sent through something like these.

Or maybe have the main unit where the side panels come off, and the dumb terminal plugs into the side via a card slot.

 

[Robert B]

Would certainly be better than this.

 

[Jon@LiionWholesale]

doing the charging specifically I could see it maybe working. The discharging for sure you wouldn't be able to do with dumb channels, without adding more cost and complexity.

 

[Robert B]

Ta Da... easy access to the switch now

 

[judo]

The reason I was asking about where the discharge stops at is because I did a full test on some
new 25r's the other day (lii-500 charger) to see how much juice was getting charged into the new
batteries and they are getting around 2050-2150 mh. Given that they are 2500 capacity I figured
they would get around 2500. So then I remembered they are rated from 2.5-4.2 V.... so my charger
cuts out automatically at 2.8-2.9 v....the volt difference between 2.5 and 2.8 is where im missing
the 300-400 mh to get 2500 mh?

 

[Jon@LiionWholesale]

The reason I was asking about where the discharge stops at is because I did a full test on some
new 25r's the other day (lii-500 charger) to see how much juice was getting charged into the new
batteries and they are getting around 2050-2150 mh. Given that they are 2500 capacity I figured
they would get around 2500. So then I remembered they are rated from 2.5-4.2 V.... so my charger
cuts out automatically at 2.8-2.9 v....the volt difference between 2.5 and 2.8 is where im missing
the 300-400 mh to get 2500 mh?

What discharge rate were you doing, or does that charger do?

At high discharge rates there's probably 300-400mAh left below 3V but usually these testers use low discharge rates like 0.2-1A and at those rates you should have 2400-ish or more even going to 2.9-3.

 

[judo]

This charger discharges at 250 and 500 ma, I believe I was using the 500ma setting.
edit.

 

[judo]

Well tried another full test yesterday. 1 battery took 1955ma and the other took 2029ma.
Charger was set to discharge at 500ma and charge at 1a. These two batteries are new
and maybe have been fully charged 15 times. I think they were made in mid 2015. They
don't look fake...could they just be a poor run of 25r's if that's possible? maybe the charger
is crap.

 

[Jon@LiionWholesale]

i'd be more inclined to believe a charger problem. Have you measured the voltage when they're "empty"?

 

[judo]

I haven't been able to catch it when its at the end of a discharge cycle.
My evic mini and sigelei 150 power off around 3.3-ish if im not mistaken,
I have check them on a multi meter and the they are within .1-.2 V of what
the evic mini says the volts are, the sigelei just gives a % indication but tends
to cut out around 35% which for some reason reads around 3.3V on my multi-
meter.

 

[Jon@LiionWholesale]

Well if it's for example 3.3V then that would explain it.