# Nitecore Digicharger D4 or Opus BT-3400



## blinkjr (Dec 30, 2015)

Hi all. Hope everyone had a wonderful Christmas and wishing all a healthy and happy New Year!

I'm looking to get a new charger. Was ready to get a Nitecore Digicharger D4. This will be used almost exclusively for 18650 LiIon cells and AA/AAA NiMH cells. I came looking here to check one last time to see if I was missing an option and discovered the Opus BT-3400.

The main advantage I see to the Opus is the Conditioning option. I know this was always good for use on NiCd cells, but I will not be using those. Have I missed something that this is useful for NiMH and/or LiIon cells?

If not, then the lower cost of the D4 seems to be the deciding factor to me.

I know there are many on this forum far smarter than me when it comes to batteries, their chemistry, and the proper care and feeding of them. I look forward to my education!

Thank you in advance for your help!

blinkjr
guided by the light


----------



## andrewnewman (Dec 30, 2015)

If you feel you need a charger analyzer, the Opus is the way to go. If you mostly are a casual user of LSD NiMH (Eneloop etc...) as well as LiIon cells, you may never benefit from the advanced features of the Opus. The Opus has a much higher current rating (see HKG review for details). If you intend to regularly charge 3-4 18650s at once, I'd go for the Opus. Otherwise the D4 is a totally adequate charger, has a nice UI and plugs directly into the wall without the need for a wall-wart. (This last point can be a mixed blessing from a heat dissipation perspective but so far I haven't had any heat issues with my D4).

Good luck.


----------



## ven (Dec 30, 2015)

Opus no question for me, faster charging too, 1a x 4 bays for AA nimh and 18650's, bays 1+4 can be 1.5a/2a rates as well for 18650/26650 cells.
Rates of 0.2/0.3/0.5/0.7/1a/1.5a/2a

The 3100 v2.2 is pretty much the same other than name


----------



## swan (Dec 31, 2015)

Opus- the d4 is a bit slow.


----------



## gyzmo2002 (Dec 31, 2015)

I first bought the D4 for my first charger but 2 weeks later, I bough the Opus for the analising function. I bought a lot of battery from Asia and I like to know if they have the capacity listed. After tested, I discharge them to 3.7v for storing.


----------



## Glow808 (Dec 31, 2015)

Hi blinkjr

I've used the D4 charger for 18650 cells. Works fine, providing length of time taken to charge so far and amount of charge put into the cell in the form of increasing blinking horizontal bar(s) as the cell is charged.

Then discovered *XTAR VC4*, with additional info in the form of how much mAh is being put into the cell as it charges, so tells me if the cell is being charged to its specified capacity or not, e.g. time to replace new cells. Also read user reviews that this charger has the ability to "revive" dead / difficult to charge cells (as with chargers, I don't leave them plugged in charging and go out for safety reasons).

I've purchased the VC4 but have not used it yet and chose this over the D4 due to the additional feature as mentioned. 

Hope that helps.


(Newbie here, please feel free to add or correct anything I may have missed off  )


----------



## j333_76484 (Dec 31, 2015)

I have the D4 for my Nitecore Flashlight batteries and. LUC V4 for my Vaping batteries. One thing I have noticed. I have them both plugged into the same multi outlet strip. And that strip is plugged into the same outlet as my TV. When I charge batts with the D4, my TV screen gets some kind of interference. Gets staticky looking lines on the screen. Whereas I can use the V4 and not get them. Different build quality between the two I am guessing.


----------



## KeepingItLight (Dec 31, 2015)

Reading this review by Bill Cushman convinced me that the *LiitoKala Engineer Lii-500* is a good alternative to the *Opus BT-C3100*. It costs less, too. I saw one on sale today at GearBest for less than $25 USD.


----------



## bella-headlight (Jan 2, 2016)

Glow808 said:


> Hi blinkjr
> 
> I've used the D4 charger for 18650 cells. Works fine, providing length of time taken to charge so far and amount of charge put into the cell in the form of increasing blinking horizontal bar(s) as the cell is charged.
> 
> ...



That is the Nitecore i4 you are describing as the Nitecore D4 has digital readouts not flashing bars.


----------



## Glow808 (Jan 6, 2016)

bella-headlight said:


> That is the Nitecore i4 you are describing as the Nitecore D4 has digital readouts not flashing bars.




"That is the Nitecore i4 you are describing as the Nitecore D4 has digital readouts not flashing bars."


Nitecore D4 charger clearly has flashing bars as the cell charges (@ 1.40 onwards>):

https://www.youtube.com/watch?v=wb1tOy8tKpo


----------



## bella-headlight (Jan 6, 2016)

Sorry, yes the D4 has flashing bars but it also has digital read outs for each slot which show volts, mA & charge time.
The i4 only has flashing charge bars which is why I thought that it was the i4 you were describing.


----------



## ChrisGarrett (Jan 6, 2016)

I just bought the BT-3400 v. 2.2 from rdana on Ebay, Monday night and it should be here perhaps tomorrow, so I'll get to see what all the hoopla is about.

I've got the i4, the VC4, the Maha C9000, the LaCrosse BC-700 and the Xtar VP2, among other chargers, but it will be nice to have some basic analyzing features for my li-ions.

I bought the 3A 12vdc car adapter to go along with it. Price was just under $50 shipped. Hopefully the fan doesn't crap out on me, but rdana is has good product support and he's here in the States.

I don't think that I'll need the SkyRC M3-Billion, but I think that it's prudent to wait for a couple of iterations and updates, if I did.

Chris


----------



## bella-headlight (Jan 6, 2016)

I have just ordered the *LiitoKala Engineer Lii-500 as I want to analyze some 18650"s that I have just got from my first ever laptop pull, although for general 18650 charging I have found my D4 perfectly good.
I also have a "Powerex" (MAHA C900) that I have been using for a number of years for my AA & AAA NIMH"s which I have found to be very good.
I suppose I better get some more 18650 powered items to justify the new charger & laptop pulls now *:laughing:


----------



## tatasal (Jan 6, 2016)

ChrisGarrett said:


> I just bought the BT-3400 v. 2.2 from rdana on Ebay, Monday night and it should be here perhaps tomorrow, so I'll get to see what all the hoopla is about.
> 
> I've got the i4, the VC4, the Maha C9000, the LaCrosse BC-700 and the Xtar VP2, among other chargers, but it will be nice to have some basic analyzing features for my li-ions.
> 
> ...




The hoopla is all true, I'm confident of it.


----------



## ChrisGarrett (Jan 7, 2016)

tatasal said:


> The hoopla is all true, I'm confident of it.



I'll let ya'll all know once it arrives.

I have some old laptop pulls that I'll probably run through it, first.

Chris


----------



## uofaengr (Jan 7, 2016)

I've had to hold off from buying the 3100 v2.2 especially when it dropped to $35 on Amazon a couple days. If I had to do it over, I'd probably gotten the Opus from the start but I'm ok with my D4. I've had no issues with it so far and haven't had any hot batteries or overcharging when left on the charger and can live with the slower rate. It's really the nerd in me coming out wanting the Opus for its analyzing function just for curiosity sake to see my cells' behavior over time.


----------



## pov (Oct 13, 2016)

I'm late to the party but here goes.Just bought and used for the first time an Opus 3400 (after reading a LOT of reviews) I really like the functions it has and what it allows you to do. Time will tell.


----------



## ChrisGarrett (Oct 14, 2016)

swan said:


> Opus- the d4 is a bit slow.



Yeah...and the Opus does a lot more, but I'm biased as a BT-3400 owner.

Chris


----------

