** PROBLEM SOLVED**: Why is Nitecore i4 charger terminating at 4.11v?

HighlanderNorth

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>>>>>>>Ok. After returning to client's home, charging all 18650's on his new Nitecore i4 charger again, then testing the battery voltage with MY multimeter, I discovered that the charger WAS properly charging them all to around 4.21v. But when I tested them with the client's DMM as I'd done before, it was still reading them at 4.11 to 4.14v. So after all, the problem wasn't with the new charger, it was with the DMM that was bought at Lowe's just 1 month ago. I didn't expect that would be the cause because it had worked fine at testing continuity of the MAF sensor in his Buick Park Ave, and a few other non-voltage related applications. Apparently it's just not all that accurate when it comes to voltage! But I'm still happy to report that my $12 DMM that I bought 5 years ago works 100%. I wouldn't have expected this result, but at least 1 person posted that possibility in this thread, so once again, this forum was helpful. Thanks. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-----------------------------------------------------------------I recently sold one of my lights(Sunwayman T20CS) to a client for $40. I literally had less than 2-3 hours of runtime on it, and 90% of that was devoted to running on high while tailstanding on my night stand to reduce the voltage of 18650's for storage. So he also had a couple really cheap 18650 lights, with cheap no-name Li Ion batteries, so I told him to order 2 Panasonic NCR18650B batteries. I also gave him the Orbtronic 2900mah 18650 that I had in the T20CS. I told him to buy a new model Nitecore I4 charger.After receiving the batteries and charger, I placed the 2 new NCR18650B and the 5 year old barely used Orbtronic 18650 into the charger and turned it on. I had to leave before it finally finished charging. He left them in the charger until finished, then removed the batteries and reboxed the charger.The next time I was there was 1 week later. I tested the voltage of all 3 batteries, and they were all around 4.1v. I was there again yesterday, so I plugged 1 NCR18650B and the 2900mah Orbtronic battery into the charger and let it run until done. I pulled them off when finished, and once again measured 4.11v in both. I verified that the charger is genuine Nitecore, and I was using a new DMM that I picked out for him a few months ago at Lowe's. Any idea why this is happening? I have an old model I4 charger that I bought in 2012 and used daily for almost 4 years for ecigarette batteries with no issues.
 
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CelticCross74

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Re: Why is a new Nitecore i4 charger terminating 18650's charge at 4.11v?

could be a couple things. Most likely your 5 year old charger just has dirty contact points. DeOxit to the chargers contact points may take care of this issue. Also, a 5 year old Orbtronic? As good as Orbs are even they lose capacity over time. You use the I4 daily for ecig battery charging? I am trying to remember...I started out with the first I4 which was slooooow to charge but did the job. I also keep the positive and negative ends of my cells clean with DeOxit. 4.11v is low but not "something is defective" low. I vape as well and have quite a few high amp unprotected cells that at times I also charge daily. Then again I moved on from NC chargers to Xtar after seeing the interior build quality between the two. I will throw out this suggestion which has worked for my first Xtar VC4 that has gone through an easy couple thousand charge cycles. Clean the I4 up. Get a couple cans of DeOxit. I wiped down the admittedly very dirty VC4 with eyeglass cleaner spray which worked surprisingly well. Then I took the DeOxit to the contact points in each slot. All problems solved. The DeOxit took care of any corrosion, dirt and film build up on the contact points like magic. The extremely well used VC4 went from having contact points so dirty that a couple slots wouldnt even recognize a cell was even in it back to working like new.
 

HighlanderNorth

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Re: Why is a new Nitecore i4 charger terminating 18650's charge at 4.11v?

could be a couple things. Most likely your 5 year old charger just has dirty contact points. DeOxit to the chargers contact points may take care of this issue. Also, a 5 year old Orbtronic? As good as Orbs are even they lose capacity over time. You use the I4 daily for ecig battery charging? I am trying to remember...I started out with the first I4 which was slooooow to charge but did the job. I also keep the positive and negative ends of my cells clean with DeOxit. 4.11v is low but not "something is defective" low. I vape as well and have quite a few high amp unprotected cells that at times I also charge daily. Then again I moved on from NC chargers to Xtar after seeing the interior build quality between the two. I will throw out this suggestion which has worked for my first Xtar VC4 that has gone through an easy couple thousand charge cycles. Clean the I4 up. Get a couple cans of DeOxit. I wiped down the admittedly very dirty VC4 with eyeglass cleaner spray which worked surprisingly well. Then I took the DeOxit to the contact points in each slot. All problems solved. The DeOxit took care of any corrosion, dirt and film build up on the contact points like magic. The extremely well used VC4 went from having contact points so dirty that a couple slots wouldnt even recognize a cell was even in it back to working like new.

The charger in question is a brand new Nitecore i4 charger. The batteries are 2 brand new NCR18650B 3400mah batteries and an older Orbtronic 2900mah battery. All of them are coming off of the brand new charger at 4.11v.
 

TinderBox (UK)

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Re: Why is a new Nitecore i4 charger terminating 18650's charge at 4.11v?

How are you measuring the voltage, have you double checked with two dmm in case one is out.

John.
 

Enderman

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Re: Why is a new Nitecore i4 charger terminating 18650's charge at 4.11v?

Lithium batteries have a voltage drop of about .05-.1v, they do not stay at 4.2v long after charging.
Did you measure immediately after taking it off the charger?
Did you try measuring the charger voltage while charging?
 

HighlanderNorth

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Re: Why is a new Nitecore i4 charger terminating 18650's charge at 4.11v?

Lithium batteries have a voltage drop of about .05-.1v, they do not stay at 4.2v long after charging.
Did you measure immediately after taking it off the charger?
Did you try measuring the charger voltage while charging?

They were still in the charger, which was plugged in when I removed the batteries and immediately checked their voltage at 4.11v. Granted, the charger had terminated the charge cycle once finished charging, but they measured 4.11v at termination. I haven't tried re-testing them with a 2nd multimeter.
 

Enderman

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Re: Why is a new Nitecore i4 charger terminating 18650's charge at 4.11v?

They were still in the charger, which was plugged in when I removed the batteries and immediately checked their voltage at 4.11v. Granted, the charger had terminated the charge cycle once finished charging, but they measured 4.11v at termination. I haven't tried re-testing them with a 2nd multimeter.
Oh, you want to check them right when they finish, because sitting in a charger when finished charging will also lose a bit of voltage.
 

Lynx_Arc

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Re: Why is a new Nitecore i4 charger terminating 18650's charge at 4.11v?

I don't have a nitecore charger but my Opus BT-C100 was only charging 18650s to 4.14v until I did the "mod" to adjust the voltage. It now charges to 4.21v
 

Nev

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Re: Why is a new Nitecore i4 charger terminating 18650's charge at 4.11v?

What mod?
My opus 3100 v2.2 charges to 4.16.
 

SoCalTiger

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Re: Why is a new Nitecore i4 charger terminating 18650's charge at 4.11v?

FWIW, my XTAR VC4 has batteries coming off around 4.1V too. That's after sitting on the charger a few minutes past charge, though. I haven't measured them "right" when they finished. It doesn't bother me too much, personally. I'd rather have batteries undercharged than overcharged.
 

Lynx_Arc

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Re: Why is a new Nitecore i4 charger terminating 18650's charge at 4.11v?

What mod?
My opus 3100 v2.2 charges to 4.16.

You have to replace or solder a resistor (smd) in parallel on the circuit board. I found a thread on another forum that shows how to do it but I'm not sure if there is similar information for the 3100 model as the boards differ.
 

Nev

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Re: Why is a new Nitecore i4 charger terminating 18650's charge at 4.11v?

You have to replace or solder a resistor (smd) in parallel on the circuit board. I found a thread on another forum that shows how to do it but I'm not sure if there is similar information for the 3100 model as the boards differ.

Ok, thanks.
 

Nev

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Re: Why is a new Nitecore i4 charger terminating 18650's charge at 4.11v?

FWIW, my XTAR VC4 has batteries coming off around 4.1V too. That's after sitting on the charger a few minutes past charge, though. I haven't measured them "right" when they finished. It doesn't bother me too much, personally. I'd rather have batteries undercharged than overcharged.

On my xtar vc4 they come off at 4.2 but on one slot it's 4.19v.
 

hiuintahs

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Re: Why is a new Nitecore i4 charger terminating 18650's charge at 4.11v?

They were still in the charger, which was plugged in when I removed the batteries and immediately checked their voltage at 4.11v. Granted, the charger had terminated the charge cycle once finished charging, but they measured 4.11v at termination. I haven't tried re-testing them with a 2nd multimeter.
To know what is going on, if you could check the voltage across the battery right before the termination ends will tell me a lot. Either the charger has too low of a termination voltage or there is quite a bit of resistance between the battery and the charger electronics. On chargers with the spring loaded contacts, there is some resistance from the negative side of the battery through a metal spring back to the electronic circuit. Since most chargers terminate charge when the current is 1/10th of the original charge current, if you can measure the voltage across the battery just before it terminates, you should see near 4.20v. And right shortly after charge it will drop but not by much (ie: 0.01v to 0.02v). A charger set right should leave the battery around 4.17v to 4.18v when charging at a 1 amp rate and when charging at 250mA, will leave it around 4.19v after charge is over with.

If the charger uses some type of pulse charging, then its a little harder to measure what is going on. You will have to measure the battery right after charge is complete. If you have tried this on several batteries and get similar results, then my guess is that your DMM is off or the charger's CV (constant voltage) is set too low. It should be set to 4.20v, but sometimes it would be nice to bump it up a little due to the fact that the battery never sees that high of voltage when there is an impedance between battery and charger's electronics. 4.11v is too low in my opinion but no harm done to the battery. I am very comfortable with batteries that end up around 4.17v to 4.19v after charge is over with.
 
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herektir

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Re: Why is a new Nitecore i4 charger terminating 18650's charge at 4.11v?

My I4 charges 18650s to 4.12 volts after an hour rest from the charger. Thats fine to me, means I'll get 800+effective full cycles out of them if i also dont deep discharge them.
 
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CuriousOne

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Re: Why is a new Nitecore i4 charger terminating 18650's charge at 4.11v?

A lot of chargers use C/10 termination method. This is safe and manufacturer recommended method, but it might not deliver full juice to the cells.
 

Mr Baz

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Re: Why is a new Nitecore i4 charger terminating 18650's charge at 4.11v?

New i4 isn't a great charger I reviewed it gets very hot a problem for Ni-MH and it tends to undercharge Li-ion though my test it wasn't as much as that. The i2 was even worse
 

HighlanderNorth

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Re: Why is a new Nitecore i4 charger terminating 18650's charge at 4.11v?

New i4 isn't a great charger I reviewed it gets very hot a problem for Ni-MH and it tends to undercharge Li-ion though my test it wasn't as much as that. The i2 was even worse

Yeah I noticed my client's new i4 charger becoming very warm while charging.
 

HighlanderNorth

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Re: Why is a new Nitecore i4 charger terminating 18650's charge at 4.11v?

To know what is going on, if you could check the voltage across the battery right before the termination ends will tell me a lot. Either the charger has too low of a termination voltage or there is quite a bit of resistance between the battery and the charger electronics. On chargers with the spring loaded contacts, there is some resistance from the negative side of the battery through a metal spring back to the electronic circuit. Since most chargers terminate charge when the current is 1/10th of the original charge current, if you can measure the voltage across the battery just before it terminates, you should see near 4.20v. And right shortly after charge it will drop but not by much (ie: 0.01v to 0.02v). A charger set right should leave the battery around 4.17v to 4.18v when charging at a 1 amp rate and when charging at 250mA, will leave it around 4.19v after charge is over with.

If the charger uses some type of pulse charging, then its a little harder to measure what is going on. You will have to measure the battery right after charge is complete. If you have tried this on several batteries and get similar results, then my guess is that your DMM is off or the charger's CV (constant voltage) is set too low. It should be set to 4.20v, but sometimes it would be nice to bump it up a little due to the fact that the battery never sees that high of voltage when there is an impedance between battery and charger's electronics. 4.11v is too low in my opinion but no harm done to the battery. I am very comfortable with batteries that end up around 4.17v to 4.19v after charge is over with.

I haven't been back to the client's home since the day before I posted this thread. Ill be back there soon. With my old model i4 charger that I bought in 2012, it charged 18650's to about 4.21- 4.22v pretty much every time, and I'd get that measurement even after pulling the battery off the charger after it had been sitting there for awhile with its charge termination having finished awhile earlier.

I can understand a battery sitting around unused and losing a small amount of voltage over a few hours or several days, but no decent battery should drop from 4.21 to 4.11 while installed in an activated charger, after its charge cycle is terminated. I would think that, if a battery lost .1v while sitting in the charger after termination, that the charger should begin charging it to top off it's now reduced voltage. No?

Anyway, I'll check the charger and batteries again within a day or 2 with a 2nd multimeter.
 
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Mr Baz

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Re: Why is a new Nitecore i4 charger terminating 18650's charge at 4.11v?

I haven't been back to the client's home since the day before I posted this thread. Ill be back there soon. With my old model i4 charger that I bought in 2012, it charged 18650's to about 4.21- 4.22v pretty much every time, and I'd get that measurement even after pulling the battery off the charger after it had been sitting there for awhile with its charge termination having finished awhile earlier.

I can understand a battery sitting around unused and losing a small amount of voltage over a few hours or several days, but no decent battery should drop from 4.21 to 4.11 while installed in an activated charger, after its charge cycle is terminated. I would think that, if a battery lost .1v while sitting in the charger after termination, that the charger should begin charging it to top off it's now reduced voltage. No?

Anyway, I'll check the charger and batteries again within a day or 2 with a 2nd multimeter.

For Li-ion not really a good idea to do a top off charge it should just terminate and that's it, they don't lose a lot of voltage not like Ni-MH which drops a fair bit even in storage for a while assuming the cell is in good condition. I'm not shocked you get lower readings on the new i4 I did many tests on that and found it was also not charging Ni-MH (possibly slow detection of delta V) to their optimal level. It's not that it's a bit off (ie an acceptable level) but I found it below 4.15V in many charges. Ideally 4.20V I don't have a problem a bit less 4.18/4.19. Some cells might be a little off too. Bottom line for me if it's below 4.15V it's not fully charging the cells and well it is a charger. Some prefer lower to extend battery life but you can just make sure you don't let the cells drop right down to charge them (same thing more cycles)

I sold my new i4 and new i2 after I finished the reviews partly because the charging wasn't as good as it should be...the other reason was as I said the heat in the Ni-MH even at the modest charging rate for 4 cells wasn't really acceptable to my mind. D4 doesn't heat cells anywhere near there yet the same mAh charging rate for 4 cells. Ditto VC4 charging heat never a problem. Unless someone wanted the single channel faster charging I would just ignore those 2 models I've used plenty of better chargers and would always suggest the D4 despite the slower speeds it's quite accurate and properly charges batteries. No idea what went wrong with Nitecore evidently the SC2 also has problems with charging and that's a more premium 2 bay charger. Seems they are a bit off with more recent models.
 
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