Nano R123 Charger -- Updated on 06/02/2005 Rev. 4

[Spacemarine]

This is the charger I bought from AW here:

Linkt to B/S/T non flashlights


Shipping from Hongkong to Germany took about 5 days and the charger and the four batteries arrived safely and without any problems.

So far, I've tested the charger with two of the R123a batteries I also got from AW. Without any battery installed, the voltage of the charger is 4.25V.

An empty cell (discharged to 3V) is charged with a current of 150mA and the charger gets noticably warm while doing that. Measuring the current a few times while charging indicates that the current drops steadily the whole time until it is around 15 mA when the LED turns green. The voltage is around 4.09V then.

If you leave the cell in the charger after the LED turned green, the charger will continue to charge, but the current gets very low because of the high voltage of the cell.

Approx. 8 hours after the LED turned green, the cell is at 4.20V and is still charged with a current of about 2mA.

I also discharged two of these cells with 0.2A down to 3V in my X-Peak 3 charger which has a display and can show me the discharged capacity. A cell which I took off the charger the moment the LED turned green had a capacity of 595 mAh (about 3-4 hours charging time. After a few more cycles, I got about 680 mAh out of a cell which was charged up to 4.2V (about 10-12 hours charging time)

I think 680 mAh is ok for a 700 mAh battery, the remaining 20 mAh could very well be a inaccuracy of my charger.

Here are bigger versions of the pictures:
backside
frontside
top

On the pictures you can see some tape wrapped around the charger, that is because I opened the charger and since it is only glued and not screwed, I wasn't able to close properly.

The big "1" on the first picture is also made by me to distinguish the cells, so yours won't have that.

Conclusion on charger:

Very nice and small charger, in my opinion worth the price. The only drawback for me is that I need an adaptor to plug it into my wall, and that is it doesen't have a cut off ability, although this feature is advertised on the packaging.
So if you have the time to charge your batteries over night and don't forget to unplug them the next day, you will find this charger very useful.

 

[4sevens]

Re: Nano R123 Charger

wow! nice thanks!
this thing definitely is NOT UL listed /ubbthreads/images/graemlins/smile.gif
but it works great for me /ubbthreads/images/graemlins/smile.gif

what is that sharp chip?

 

[Doug S]

Re: Nano R123 Charger

[ QUOTE ]
4sevens said:
wow! nice thanks!
this thing definitely is NOT UL listed /ubbthreads/images/graemlins/smile.gif
but it works great for me /ubbthreads/images/graemlins/smile.gif

what is that sharp chip?

[/ QUOTE ]
That 4 pin Sharp component on the power input side of the board is an optoisolator. Undoubtedly it is used in some feedback loop from the lower voltage portion of the board to the higher [input] side of the board.

 

[Spacemarine]

Re: Nano R123 Charger

[ QUOTE ]
Doug S said:

That 4 pin Sharp component on the power input side of the board is an optoisolator.

[/ QUOTE ]

Are you sure of that? The package says "Microprocessor controlled auto cut off"

If that isn't the microprocessor, I can't find it...

 

[4sevens]

Re: Nano R123 Charger

that pc837 is an optocoupler - it's not a microprocessor.

I don't believe there is a microprocess inside. Those transistors
are regulating the charging.

Soo.... despite the word microprocessor showing up TWICE on the
packaging, it's not true. Actually it doesn't need microprocessor.

Regardless, it's still a very nice charger. I haven't opened mine up,
I was just looking at spacemarines pictures /ubbthreads/images/graemlins/smile.gif

 

[Doug S]

Re: Nano R123 Charger

[ QUOTE ]
Spacemarine said:
Are you sure of that?

[/ QUOTE ]
Yes.

PC817 .pdf

 

[Billson]

Re: Nano R123 Charger

[ QUOTE ]
4sevens said:
that pc837 is an optocoupler - it's not a microprocessor.

I don't believe there is a microprocess inside. Those transistors
are regulating the charging.

Soo.... despite the word microprocessor showing up TWICE on the
packaging, it's not true. Actually it doesn't need microprocessor.

Regardless, it's still a very nice charger. I haven't opened mine up,
I was just looking at spacemarines pictures /ubbthreads/images/graemlins/smile.gif

[/ QUOTE ]

I'm clueless about such things so in this case, is it still a smart charger?

Thanks.

 

[AW]

Re: Nano R123 Charger

It is still considered a smart charger because it has regulated charging current and voltage.

 

[Spacemarine]

Re: Nano R123 Charger

[ QUOTE ]
AW said:
It is still considered a smart charger because it has regulated charging current and voltage.

[/ QUOTE ]

I'm not sure of that. Neither the current nor the voltage seems to be regulated. The only thing the charger seems to do is outputting a voltage of 4.25V with a high internal resistance, so that while charging the current starts at 150mA and drops to 12mA when the LED turns green at around 4.08V.


I also updated the review once more with my newest measurements about the capacity of the cells and the current and voltage of the charger a few hours after the LED turned green.

I've heard often that trickle charging can hurt the cells and that the current should be cut off when the cell is fully charged (just as advertised on the packaging, but not true with the charger). Is this also true when the cell is only charged with 3-4 mA at 4.18V?

 

[4sevens]

Re: Nano R123 Charger

I verified the charging rate to be 140ma with the cell at 3.6v.
I wonder if the 220v source will charge it faster /ubbthreads/images/graemlins/grin.gif

 

[Spacemarine]

Re: Nano R123 Charger

I just updated the review once more (and perhaps the last time)

I rewrote the section on the batteries, which now perform very good, 685 mAh was the best I got out of them. I also added two pics and a conclusion. Please tell me if you have any suggestions or ideas or want to know something about the charger.

Andre

 

[modamag]

Re: Nano R123 Charger

A great review for a very nice charger.
First it's collecting flashlights now I'm starting to collect charger ...
Vanson, Panasonic, Pilas, batterystation, Triton, LaCrosse, and now this ...
This wallet's is gonna stretch really thin now /ubbthreads/images/graemlins/mpr.gif

 

[Halibut]

Re: Nano R123 Charger

I received my Nano + R123 package from AW yesterday. Fired up my Aleph 2/NG1000/TWOK on a partially depleted cell (read 3.99V on the Fluke) and it ran in full regulation for about 30 minutes. No flickering on low. Outstanding cells, great little charger. Thanks, AW!

-Dan

 

[wptski]

Re: Nano R123 Charger

[ QUOTE ]
Spacemarine said:
[ QUOTE ]
AW said:
It is still considered a smart charger because it has regulated charging current and voltage.

[/ QUOTE ]

I'm not sure of that. Neither the current nor the voltage seems to be regulated. The only thing the charger seems to do is outputting a voltage of 4.25V with a high internal resistance, so that while charging the current starts at 150mA and drops to 12mA when the LED turns green at around 4.08V.


I also updated the review once more with my newest measurements about the capacity of the cells and the current and voltage of the charger a few hours after the LED turned green.

I've heard often that trickle charging can hurt the cells and that the current should be cut off when the cell is fully charged (just as advertised on the packaging, but not true with the charger). Is this also true when the cell is only charged with 3-4 mA at 4.18V?

[/ QUOTE ]
The Duratrax ICE charger has a Li-Ion/Li-Poly trickle charge also based on constant voltage. It appears to start at 90ma and stops when the cell draws less than 30ma. The Triton charger stops when the cell draws less than 100ma.

 

[PeLu]

Re: Nano R123 Charger

[ QUOTE ]
4sevens said:
I wonder if the 220v source will charge it faster

[/ QUOTE ]

I do not think so. charge rate will be independent from the input volatge in the given range.

But what all of these inexpensive Li-Ion chargers do I've seen so far:
The do not slow charge a deep discharged cell and they do not shut off current completely at a fully charged cell, that means that you have to remove the cell after maybe 8 hours to prevent damage in the long run.

 

[Doug Owen]

Re: Nano R123 Charger

[ QUOTE ]
4sevens said:
that pc837 is an optocoupler - it's not a microprocessor.



[/ QUOTE ]

Yup, the little rascal is part of a switcher. The stuff to it's right are 'mains related' and a serious shock hazard. The opto coupler is the light link between the battery charger (safe) side and the input (lethal) side of the transformer upper right. The give away is the cap laying on it's side, 4.7 mfd at *400 Volts*. That's rectified mains voltage (220 Vrms times 1.414 for peak). The stuff on the right runs on this voltage.

A fun thought came to mind WRT the concern about low trickle current when the cell was fully charged. How about putting say 2,000 ohms across the battery so you drain that same 2 mA away?

Doug Owen

 

[rikvee]

Re: Nano R123 Charger

Left a 700mAh R123 in my Nanocharger for a few days, it came out reading 4.29V..... oops!
How much does that shorten battery life by?

 

[AW]

Re: Nano R123 Charger

For a few days ??? A charge of 4.29V won't kill your cell instantly. However, long term mileage certainly will suffer. I can't say how much but you should expect no less than 15% shorter life ( reduced cycles and/or lowered capacity ). Good luck!

 

[goldserve]

Re: Nano R123 Charger

Got my Nano charger today too. Nice review. I have a charger coming from djpark. That one is truely microprocessor controlled and runs off usb. Waiting to get it now =D

 

[MY]

Re: Nano R123 Charger

goldserve, please post a link to the djpark charger. thanks.

Regards.