charging with nano charger

Sakkath

Newly Enlightened
Joined
Feb 27, 2007
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Sweden
Hello!

I have Aw's Nano charger and protected RCR's (750mah).

I tried to charge a battery last night for the first time. I was a little nervous after reading of the various battery accidents with Li-ion batteries:poof:.

So before the charge I bought a 6kg fire extinguisher (dry powder) "chemical gloves", safety googles, and a halv-mask breathing protection for organic vapours.. might be a bit overkill but i wanted to be on the safe side :naughty:

How long time does the charge take? I don't know exactly how long I charged the battery.. but I think i started around 18:30 and charged the battery to 22:40 then I had to go to bed so I unplugged it. I'm not sure but I think the Diode on the charger went from red to a more orange tint in the end (could be me tired as well).

Is it harmfull to the battery in any way to "unplug" it before it is ready? The diode should go from RED to GREEN when it's ready, right?

Another question, can I check the Battery with the Ztester?
 
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I use two Nano-chargers to charge the rechargeable 123-cells I have, both protected and non-protected.
I also have the Ultrafire 139, but have not yet modded it to take the 123-cells, nor do I have the spacers needed.
The Ultrafire 139 also have a high charge-current compared to the Nano's, so for a quick charge the 139 would be better.
But a rechargeable 123 cell, taken from a light when it dims or blink, and inserted in the Nano-charger, takes about 24 hours to reach 4.20 Volts!
So for safety, the Nano is great!
It does go over 4.20 Volts if left too long in the charger, but should take some hours to make much over the recommended 4.20 Volts.
I check the batteries with a Volt-meter while still in the charger, and also some time after the charge has ended with my ZTS-tester.
So far my Li-ion batteries are fairly new, not much over one year any of them,so the Volt-meter readings are giving as much reliable state-of-health-status as the ZTS is.
But when they grow older, and gets to the point where they start failing, and will have to be replaced, the ZTS will be more valuable.
Of course, better sooner than sorry! But the risk with these batteries is a bit overemphasized!
Try having the charger while charging someplace not too close to very flammable objects, maybe just put a metal-plate under it for safety (I have a computer with a metal-cabinet under it.), be sure there is fresh air being supplied (Not in a closed closet!), and don't leave the charger unattended for too long.
I have not found any information that partial charging of these Li-ion cells is damaging to the cells.
They age, and loose capacity gradually from the time they are manufactured, but else they don't "learn" as older type rechargeable batteries are known to do.
 
I use two Nano-chargers to charge the rechargeable 123-cells I have, both protected and non-protected.
I also have the Ultrafire 139, but have not yet modded it to take the 123-cells, nor do I have the spacers needed.
The Ultrafire 139 also have a high charge-current compared to the Nano's, so for a quick charge the 139 would be better.
But a rechargeable 123 cell, taken from a light when it dims or blink, and inserted in the Nano-charger, takes about 24 hours to reach 4.20 Volts!
So for safety, the Nano is great!
It does go over 4.20 Volts if left too long in the charger, but should take some hours to make much over the recommended 4.20 Volts.
I check the batteries with a Volt-meter while still in the charger, and also some time after the charge has ended with my ZTS-tester.
So far my Li-ion batteries are fairly new, not much over one year any of them,so the Volt-meter readings are giving as much reliable state-of-health-status as the ZTS is.
But when they grow older, and gets to the point where they start failing, and will have to be replaced, the ZTS will be more valuable.
Of course, better sooner than sorry! But the risk with these batteries is a bit overemphasized!
Try having the charger while charging someplace not too close to very flammable objects, maybe just put a metal-plate under it for safety (I have a computer with a metal-cabinet under it.), be sure there is fresh air being supplied (Not in a closed closet!), and don't leave the charger unattended for too long.
I have not found any information that partial charging of these Li-ion cells is damaging to the cells.
They age, and loose capacity gradually from the time they are manufactured, but else they don't "learn" as older type rechargeable batteries are known to do.

Thanks for the replies, some followup questions:
When the Nano is done, it should turn green. Charging colors first RED, then it was yellowish, then it was yellowish+green (I thought it was green at first but up close it looked more yellowish?) As I thought it was GREEn I unplugged it, although i'm sure I have not chaged it for 24 hours, maybe half that time.

So the Ztester can test RCR's? The model I have says "3V lithium cr123a, cr2 and crv3". So I'n my feeble brain it would mean by putting say a 70-80% charged cell to the Ztester would still show 100% charged, am i wrong??

I have a multimeter too, never used it though. Exactly how do u test the battery when it's in the charger?
 
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Thanks for the replies, some followup questions:
When the Nano is done, it should turn green. When I charged it was first RED, then it was yellowish, then it was yellowish+green (I thought it was green at first but up close it looked more yellowish?)

It should be green when the charger is reaching the destined max voltage, I seem to remember this on my Nano's is somewhere around 4.15 Volts.
But it could be kept there still a few hours, I count about 1.5 hour per. 0.1 Volts up from here, up to around 4.20 Volts, getting slower all the time.
This is trickle charging, and most chargers will increase the voltage on the batteries over time after the selected voltage cutout is reached, this is due to the nature of these chargers.

So the Ztester can test RCR's? The model I have says "3V lithium cr123a, cr2 and crv3". So I'n my feeble brain it would mean by putting say a 70-80% charged cell to the Ztester would still show 100% charged, am i wrong??

No, your tester can not test the rechargeable 3.7 Volts batteries!
Only the new one have this capability!

I have a multimeter too, never used it though. Exactly how do u test the battery when it's in the charger?

Just use the meter in DC Volt measuring-mode, select the voltage range the closest over the voltage of the batteries you are testing ( 3 Volt batteries, range 1-10 Volts if this is the closest range to your battery voltage on your meter ), and use the probes to measure voltage over the battery itself, from + to -.
In the Nano, the battery poles are very easy accessible when the battery is still in the charger.
I take them out when 4.20 Volts is reached, this is maximum capacity voltage of these cells, but 4. 22 is not dangerous just not recommended.
 
OK! Thanks!:thumbsup:

I'll try to measure with the multimeter then..
 
Ok, a little problem :duh2:

There are three holes for the probes:
10ADC, COM and V(something)ma

Wich goes where? :naughty:
 
Ok, a little problem :duh2:

There are three holes for the probes:
10ADC, COM and V(something)ma

Wich goes where? :naughty:

The black probe goes to COM, this is the one you connect to the - side of the battery.
The red probe goes to V, this is the one you connect to the + side of the battery.
The 10ADC is for measuring DC Amperes/current, up to maximum 10 Amps.
But I don't think you should use this feature before you have done some reading about the use of a multimeter and current measurements!
The voltage measuring part is no problem, current measurements involve also putting a load on the battery, and should be done only if you know what you are doing.
 
The black probe goes to COM, this is the one you connect to the - side of the battery.
The red probe goes to V, this is the one you connect to the + side of the battery.
The 10ADC is for measuring DC Amperes/current, up to maximum 10 Amps.
But I don't think you should use this feature before you have done some reading about the use of a multimeter and current measurements!
The voltage measuring part is no problem, current measurements involve also putting a load on the battery, and should be done only if you know what you are doing.

Thanks again! I will read up some on measuring current :thumbsup:
 
It should be green when the charger is reaching the destined max voltage, I seem to remember this on my Nano's is somewhere around 4.15 Volts.
But it could be kept there still a few hours, I count about 1.5 hour per. 0.1 Volts up from here, up to around 4.20 Volts, getting slower all the time.
This is trickle charging, and most chargers will increase the voltage on the batteries over time after the selected voltage cutout is reached, this is due to the nature of these chargers.
Shouldn't this be 0.01 Volts up from there? My AAA size Nano charger scales like that.
 
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Shouldn't this be 0.01 Volts up from there? My AAA size Nano charger scales like that.

Different charger, different batteries equals different values.
Yours is the AAA Nano-charger, we are talking the RCR123 3.7 Volt Nano-charger with RCR123 cells.
Using the same charger and 18650 cells, the recharge time from normal depleted to 4.20 Volts is about 48 hours!
And the figure is a rough estimate, getting lower the higher up from 4.15 Volt you get.
From around 4.20 Volt, 0.01 Volt is more correct than 0.1 Volt.
 
Hmm

I used the multimeter on the battery.

Put red probe on +
And black on -

It showed 4.06V

But now It's not showing anything, when I place the probes it's:
"0.00V"

Did I break it?
 
I doubt you ruined anything!
Just be sure you have good metal-contact between the probe-ends and the battery-poles when measuring.
Maybe turn the meter on and off, if you left it on without using it for a while.
 
It showed 4.06V

But now It's not showing anything, when I place the probes it's:
"0.00V"

Did I break it?



good idea, when you are taking an important measurement, or when you get a 0V measurement, is to FIRST switch your meter to the resistance scale (with or without audible continuity buzz/beep/sound/noise/etc.) and touch your meter leads together and make sure that one of your meter leads has NOT developed an OPEN. this often happens right at the high flex/high-stress area near where it enters the probe or, less frequently, at the connector where it plugs into your meter.

you'd be surprised, if you use your meter a lot, how often this can occur.

let's say one of them (extremely rare for both of them to go bad AT THE SAME TIME - did they both get cut somehow??? even more embarassing is are they both plugged into the meter? --- DON'T ASK!!!) not sure which lead has the problem? two solutions: 1) test each lead individually for continuity with another meter, or 2) gently, but firmly tug/pull on each lead's wire near the probe and connector, while holding the connector or probe with the other hand, and look for the lead's insulation to stretch a bit - that's the sign that the wires within are broken.

very easy to fix, generally, but your leads become progressively shorter by an inch or two or three each time your repair them. i have some VERY OLD and somewhat shorter leads on some of my favorite OLD meters. however, if they ever get too short, it's generally a simple matter to afix new leads to the original probes and connectors.


***DON'T FORGET TO SWITCH YOUR METER'S SCALE/FUNCTION BACK TO *VOLTS* OR VDC SCALE/FUNCTION BEFORE CHECKING THE VOLTAGE OR YOU CAN KISS YOUR METER'S FUSE...

'TA-TA'/Adios/GoodBye/Aloha/Sayonara/Zai Jian/An nyung he ke seo/Do yi di nyah/Arrivederci/Dos Vedanya/Auf Wiedersehen/Au Revoir....

i think you get the idea. (don't ask how i KNOW this!!! you'll always find extra fuses with MY meters - you can't always teach this old dog new tricks!!! best to learn from my absentmindedness!)
 
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I doubt you ruined anything!
Just be sure you have good metal-contact between the probe-ends and the battery-poles when measuring.
Maybe turn the meter on and off, if you left it on without using it for a while.

I don't know what I'm doing wrong.. I have good metal contact, tried switching on and off. Same result every time. I place the positive probe in the vent hole and the negative on the metal plate on the back.

But it can't be completely dead. I got it up to 0.07V when I tried the last time.. ?
 
Did you do the test as instructed in the above post?
To make sure your test-leads is not broken?
 
check the fuse in the meter. it may be blown. were you doing anything but performing a voltage measurement with the leads in the correct jacks? if you set your leads or meter up incorrectly for whatever measurement you were taking, you could have blown the fuse in the meter performing some measurements improperly or with the meter incorrectly set up.

check the meter's fuse if you haven't done so already.

set you meter up for VAC and see if you can measure the voltage at the wall outlet. NO? if the LED on the charger is illuminated, your meter is NG. Check the fuse.
 
Ok, i managed to open the meter.
I don't know what a broken fuse looks like. At first I thought it might have blown. But when I ispected it a bit closer I noticed a barely visible spiderline thin thread, seemed intact.

Another thing I noticed inside the meter: The plastic area above the "COM" hole has burnmarks! :eek:oo:
The black test lead has slight burns on the metal insert part from sitting in the "COM" hole.:eek:

I have not been meassuring on anything else, just the battery. And the meter is brand new..:thinking:
 
Ok, i managed to open the meter.
I don't know what a broken fuse looks like. At first I thought it might have blown. But when I ispected it a bit closer I noticed a barely visible spiderline thin thread, seemed intact.

Another thing I noticed inside the meter: The plastic area above the "COM" hole has burnmarks! :eek:oo:
The black test lead has slight burns on the metal insert part from sitting in the "COM" hole.:eek:

I have not been meassuring on anything else, just the battery. And the meter is brand new..:thinking:

A couple of things that are important to remember about a DVM:A DVM set to measure voltage presents a very high impedence (1 Meg-Ohm or so). Voltage measurements are taken ACROSS a circuit. Little to no current flows through the meter. Its difficult to damage anything with a DVM set to read voltage.A DVM set to measure current presents a SHORT. Current measurements are taken IN the circuit. All of the current flows through the meter. It is extremely easy (and very common) to damage things with a DVM set to read current.So, if you set your DVM to read current and place the leads across the circuit-of-interest you just shorted out the circuit and most or all of the available supply current will have passed through your meter.The DVM has 3 connections: V, Common and A. The impedence between V and Common is about 1 Meg. The impedance between A and Common is about 1 milli-ohm, basically a dead short (actually it is a shunt).
 
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