Eachine Gemini 2100 and D800 Charger Review

Eachine's new Gemini 2100 and D800 AC/DC chargers are aimed at the budget minded while still offering some nice features that are worth a look. The Gemini 2100 is a dual output charger and the D800 has a single output...

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Introduction

There are a lot of chargers on the market and some offer more features than others with varied price ranges. Having a decent charger makes r/c life easier. Eachine's new Gemini 2100 and D800 AC/DC chargers are aimed at the budget minded while still offering some nice features that are worth a look. The Gemini 2100 is a dual output charger and the D800 has a single output. These two do have other differences that are important to keep in mind when choosing between them so read on to learn which charger might be suitable for you.

What's in the Box

D800

Inside the D800 box you'll find the charger, manual, battery lead with a T connector, AC power cable and DC power input cable.

Gemini 2100

Inside the Gemini 2100 box you'll find the charger, manual, AC power cable, DC Power Cable, two balance boards, two battery leads with a T connector on one and an XT60 connector on the other.

Specifications

D800

  • Input Power: AC 100-240V, DC 11-18V
  • Wattage: 80W Charge, 15W Discharge
  • Charge Current Range: .1-7A
  • Discharge Current Range: .1-1A
  • Balance Current Drain: 300mAH per cell
  • Lipo Cell Count: 1-6
  • NiCd/NiMH Cell Count: 1-15
  • Pb Voltage: 2-20V
  • Weight: 437g no cables
  • Dimensions: 136x172x56mm
  • Price: $42.99
  • Available at: Bangood

Gemini 2100

  • Input Power: AC 100-240V, DC 11-18V
  • Wattage:Dual 80W Charge, 15W Discharge
  • Charge Current Range: .1-7A
  • Discharge Current Range: .1-1A
  • Balance Current Drain: 300mAH per cell
  • Lipo Cell Count: 1-6
  • NiCd/NiMH Cell Count: 1-15
  • Pb Voltage: 2-20V
  • Weight: 930g no cables
  • Dimensions: 96x138x192mm
  • Price: $82.99
  • Available at: Bangood

How they work

Both chargers are capable of charging Lipos, NiCD/NiMH and lead acid batteries. Those are the most common battery types nearly any charger should be able to handle. Another chemistry type that both of these chargers can work with is LiFE. This is a newer cell type and not as widely used currently, but it's nice that both chargers have that capability. The D800 does have a leg up on the Gemini 2100 with its ability to charge High Voltage (HV) lipo packs. These batteries can be charged up to 4.35V per cell and the D800 has that ability. I'm not sure why the Gemini 2100 does not offer that feature, but that is something you should know before buying.

The user interface on both of these chargers and their operation is nearly identical and very common across many brands of chargers. You can easily set the battery type, charge rate, and cell count via the 4 buttons. The Gemini has an extra button on the front that changes the channels. There is a red LED light on either side that shows which channel the screen is currently showing. The screens are backlit and easy to read in both daylight and at night and it shows you important info like the charge rate, battery voltage, charge time and capacity put into the battery. While charging you can push the status increase button to change screens and see the individual cell voltages. When the charge is complete it says "full" and beeps for a moment to alert you that it is done.

The balancing works very well. I balanced charged an old battery that was out of balance and when the charge was complete, all 3 cells were reading 4.2V exactly. These chargers also offer programming features and allow you to store up to 5 different battery charge settings you so can quickly change the program without having to change the parameters every time you charge a different battery. Both chargers are 80W max power with the Gemini 2100 having two separate 80W channels. That means you can charge a 3S Lipo up to about 6A. A 6S lipo can only go up to about 3A. That's just something to keep in mind and if you have a lot of high capacity high cell count packs, you'll probably want a charger with more power. 80W is great for most applications though.

Video

Photos

Conclusion

I really like these two Eachine chargers for what they are. The D800 is fairly small and light and will take care of HV lipo packs just fine. The Gemini 2100 is also small and very convenient to travel with and the dual charger ports is a huge plus. Both chargers can operate on AC or DC input voltage making them versatile and easy to find a place to charge just about anywhere. I wish the Gemini 2100 had HV lipo support, but when you look at the cost of these chargers, the value is still exceptional. If the feature set of these chargers meets your needs, they are definitely worth a look.

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Mar 22, 2016, 12:20 PM
Gettin' back into flyin'
MartMX's Avatar
These chargers sure do have a different form factor, but still the basic 4 button interface. I would like to see a charger that requires the least amount of user interaction to charge a variety of batteries. Maybe slide switches to select LiPo, LiFe, NiMh and the cell count.

I want to be able to plug a battery in and balance charge it without pressing anything. My set of HobbyKing compact chargers will do that for LiPo, but not LiFe.
Mar 24, 2016, 12:19 AM
Permanently Banned
Isaac96's Avatar
The same firmware as the Accucell/Imax/SkyRC.
Mar 24, 2016, 07:47 PM
Registered User
Is the Dean plug that comes with the charger female?

(On the D800)
Last edited by DroneRequired; Mar 24, 2016 at 07:48 PM. Reason: Extra Info
Mar 24, 2016, 08:02 PM
RCG Staff
Jason Cole's Avatar
Quote:
Originally Posted by DroneRequired
Is the Dean plug that comes with the charger female?

(On the D800)
No it's a male plug.
Mar 24, 2016, 08:30 PM
Registered User
Quote:
Originally Posted by Jason Cole
No it's a male plug.
Ok, thank you.
Mar 24, 2016, 11:16 PM
Registered User
Could you know of a female t plug to female JST plug? So I can charge my 1s Lipos.

Edit: Found
Last edited by DroneRequired; Mar 26, 2016 at 04:42 PM.
Mar 25, 2016, 06:46 AM
RCG Staff
Jason Cole's Avatar
I'm sure someone sells that or you could make one.
Mar 26, 2016, 04:22 AM
Fan of just about anything RC
SoloProFan's Avatar
Jason, does your D800 offer 15W discharge? Mine won't go higher than 5W. Same with the Gemini, when I select 1A discharge on a 2S LiPo, the discharge current won't go higher than 0.6A, just like on a "vanilla" B6.

Also, while the D800 has the option to charge Li Hv, it has dropped support for Li-Ion as result.
Mar 26, 2016, 07:57 AM
RCG Staff
Jason Cole's Avatar
Hey Solo,
Good find. Mine only goes to .6A on a 2S as well. I don't even see why they have a discharge mode on these for Lipos anyway. There is no need to use it. The only time I ever discharge is using the Storage Mode. Otherwise I'm discharging in my aircraft the fun way.
Mar 26, 2016, 01:15 PM
Fan of just about anything RC
SoloProFan's Avatar
Quote:
Originally Posted by Jason Cole
Hey Solo,
Good find. Mine only goes to .6A on a 2S as well. I don't even see why they have a discharge mode on these for Lipos anyway. There is no need to use it. The only time I ever discharge is using the Storage Mode. Otherwise I'm discharging in my aircraft the fun way.

I was hoping it was just mine, but it seems that all are like this then. Does your D800 also show "Yuki Model Karate Charger" in the display, when it powers on?

I do see some use for a stronger discharge function. When cycling cells that have been "dormant" for a while, as these tend to be a little "lazy" the first few uses. I've had a few times one of my quads hitting early LVC, if a lipo had not been used for a while. A few cycles later it performed as normal. There are other ways to do a faster discharge, but if a charger is capable of fast discharge, that is even more convenient, as you can use the cycle program, and have the entire process run automatically.
Mar 26, 2016, 09:50 PM
RCG Staff
Jason Cole's Avatar
Quote:
Originally Posted by SoloProFan
Does your D800 also show "Yuki Model Karate Charger" in the display, when it powers on?
It sure does. Apparently these chargers know Kung Fu!!!
Apr 14, 2016, 10:22 AM
Registered User
I am realy disapointed with this charger, Lot of money , it is basic.
They advertise it but do not have USB wire for it.

Has anybody tried to hack one ?
Apr 15, 2016, 02:47 AM
Registered User
Here is my review:
https://www.rcgroups.com/forums/show....php?t=2645634
Apr 15, 2016, 03:23 AM
ancora imparo
jj604's Avatar
Mine for the 2100 is here.

https://www.rcgroups.com/forums/show....php?t=2641168

John


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