Test/Review of Charger NiteCore Intellicharger i4 2014

[size=+3]Charger NiteCore Intellicharger i4 2014[/size]





This is an updated version of the i4 charger as can be seen below, the box is marked 2014 version. The charger is a 4 channel charger that can handle both LiIon batteries and NiMH batteries.
One of the visible updates is the metal rail for the battery slider.



The cardboard box lists lot of specifications, battery types and features.



The box contains the charger, a mains cable, manual and a warranty card.



The charger has two power connectors, one for mains input (100-240VAC 50/6+Hz) and one for 12 VDC input.



The charger has a blue led in the corner, that is on when power is on. For each battery there are 3 yellow leds to show the charge state or flash due to an error.
The scale on the yellow leds are not very linear, the first one will only flash a short time.



The slots uses the usual construction and works well. They can handle batteries from 30mm to 69.3 mm long.
That excludes some of the longest batteries, especially some protected 26650.








The charger can handle 69.3 mm long batteries, inclusive flat top cells.
With C and 26xxx batteries there are some restrictions due to battery size.
With smaller batteries the charge current can be too high, this will reduce the lifetime of the batteries. There is a trick to get around this, see below.



[size=+2]A look inside the charger[/size]

Nitecore asked me to show the inside of the charger:



The screws was placed under the four feet, this is very common praxis.



The 3 leds for each battery is on a separate circuit board.









[size=+2]Measurements[/size]

• Discharges with 0.8mA when not connected to power
• Charges with 0.2mA when LiIon battery is full.
• Will not restart if battery voltage drops.
• With a empty battery the charger will flash the 3 yellow leds and pulse the current.
• At 0.8 volt the charger will assume NiMH and start charging.
• The charger will assume NiMH below 2 volt and LiIon above 2 volt.
• Charge will restart charging after power loss or battery insertion.
• C batteries are best charged in center slots, in the outer slots the plus pole slides off the plus terminal. This limits the charging to one C cell at a time.
• The charger has two charge circuit, one is serving slot #1 and #3, the other is serving slot #2 and #4.
• When a charge circuit has batteries in both slots, in will use 2 second on each in a 4 second cycle.

[size=+1]LiIon charging[/size]



The charger does a simulated CC/CV charger with a 50mA termination, this is fine.
I do not know where the jump in current comes from, it does make the charging a bit slower, but does not affect the quality of the charging.





The other channels has the same CC/CV curve, but without the jump. I wonder about the variations in the termination current.




There is not much variation in charge time for the different capacities.



The old 16340 cell, does also have a jump in current, here the reason is obvious: The voltage gets too high and the charger has to do a fast adjustment in the current.




The two other small batteries are also charged fine. It looks like the jump in current is used when the charger detect a high voltage.



With more batteries in the charger it will alternate between the slots and the effective charge rate is halved. Due to the low charge rate, there is not that much heat.



When using the DC input the charger needs slightly above 0.8A. Notice the temperature is about the same with DC supply as with mains supply, i.e. the build in mains supply do not generate much heat.



M1: 54,5°C, M2: 38,0°C, M3: 38,6°C, M4: 36,3°C, M5: 33,0°C, HS1: 71,4°C



M1: 55,0°C, M2: 35,8°C, M3: 36,5°C, M4: 34,4°C, M5: 31,6°C, M6: 48,4°C, HS1: 60,9°C
It is interesting to see where the heat is and the look at the circuit board photo. It looks like the heat is generated around the two inductors marked "101", that is the charging circuits.



When powered on, the charger needs some time to startup. As can be seen it uses about 20 seconds, before engaging full charge current.



A closer looks at the pulsing when charging.



When a charge channel charges two batteries it will use 50% of the time on each.



When one of the batteries are full, it will use the full current on the other battery. I wonder if it is a software bug that the pulses are very fast.



[size=+1]NiMH charging[/size]



The NiMH charging stops on voltage, not -dv/dt, this means the batteries may not be fully charged. To compensate for that the charger is using a fairly high trickle charge current.
This works, but it not the best charge algorithm and it is a good idea to remove the batteries within a few hours when they are full.





All channels works the same.



The eneloop XX needs a bit more time and it looks like it was just about full (There is a small temperature rise). The trickle charger stays at a high level.



The AAA cell does charge fine. The manual warns against charging a NiMH AAA cell at full current, but that is not really a problem as long as the battery is removed when the charger is finished.



The charger is very fast to detect a full cell.



With four cells, the charge current is halved.



Charging NiMH uses less current on the DC input, compared to LiIon cells, only about 0.5A.



M1: 40,2°C, M2: 40,5°C, M3: 37,3°C, M4: 34,2°C, M5: 53,2°C, HS1: 74,0°C



M1: 37,6°C, M2: 37,7°C, M3: 35,3°C, M4: 33,1°C, M5: 51,0°C, M6: 47,1°C, HS1: 61,0°C



NiMH needs about 30 second to start.



The pulses looks the same as on LiIon.



With two NiMH the charger uses 50% of the time on each.



The trickle charge uses smaller current pulses, this looks like the same type of pulses that is used during startup.



[size=+1]LiIon+NiMH charging[/size]



With one NiMH battery and 3 LiIon batteries, the charger has no problem with charging the NiMH.



With one LiIon and 3 NiMH batteries, the LiIon is also charged fine.
The temperature curve is for one of the NiMH batteries and it can be seen that when they are finished, there is slightly more current for the LiIon charging.



When the charger is finished with a LiIon battery, it will usual redirect the current to the other slot on the charging circuit, but not when a NiMH battery is included.



It is the same the other way around.



Even with two NiMH batteries.
It is easy enough to see why with NiMH, it needs the charger circuit to trickle charge, but I wonder why it also does it with a LiIon cell.

This brings me around to the trick that can be used when charging small LiIon batteries: Simply put a NiMH battery in the other slot, it does not really matter if it is full or empty (A old worn out NiMH is perfect).
I.e. to charge a small LiIon in slot #1, but a NiMH in slot 3.
I.e. to charge a small LiIon in slot #2, but a NiMH in slot 4.




Testing the mains input with 2500 volt and 5000 volt between mains and low volt side, did not show any safety problems.



[size=+2]Conclusion[/size]

The charger does a good charging on LiIon, with NiMH it is best to remove them a few hours after the charger has finished.
I would have liked the slots 2 mm longer, some protected 26650 are rather long.

Compared to the V2 i4 the charger has gotten metal rails for the sliders (nice) and a changed NiMH charging. With the added trickle charging the batteries will be filled, if they are left in the charger, but they will also be over charged if left to long, due to the high trickle current.

The i4 is still a good universal charger, if you have the patience for it.



[size=+2]Notes[/size]

The charger was supplied by a Nitecore for review.

Review of old i4 (V2)

Here is an explanation on how I did the above charge curves: How do I test a charger

Thanks for this review HKJ!

Excellent review. HKJ! :thumbsup:

Thanks a lot for doing this test for all of us.

here they claim -dv/dt

seems like yet another nitecore false claim

Overclocker said:

here they claim -dv/dt

seems like yet another nitecore false claim

Click to expand...

Not necessarily, they have probably just placed the maximum voltage limit a bit low.
A very good example of this is the SKY charger, out of the box it terminates on maximum voltage, but if the maximum voltage limit is raised a bit it will use -dv/dt (The SKY charger has some unusual settings possibilities). You can see it in my review: http://lygte-info.dk/review/Review Charger SkyRC NC2500 UK.html

Other brands of batteries may terminate using -dv/dt, because the maximum voltage varies slightly with brand (and with temperature).

If I find a quality brand with lower maximum voltage, I will add it to my tests in the future, but at the current time I do not have much time to experiment (There are way to many chargers in queue).

HKJ said:

Charger NiteCore Intellicharger i4 2014

Conclusion

The charger does a good charging on LiIon, with NiMH it is best to remove them a few hours after the charger has finished.

Click to expand...

I know nothing about battery chargers, but am doing my research. Never used rechargeable AA batteries either. What is meant by "with NiMH it is best to remove them a few hours after the charger has finished"?

It sounds like charging is done when all lights are solid green, but when the charging is done, how long can you leave them in the charger before removing them?

wingspar said:

I know nothing about battery chargers, but am doing my research. Never used rechargeable AA batteries either. What is meant by "with NiMH it is best to remove them a few hours after the charger has finished"?

It sounds like charging is done when all lights are solid green, but when the charging is done, how long can you leave them in the charger before removing them?

Click to expand...

Most NiMH chargers does not turn completely off when finished charging, but continues to apply a small current, this is called trickle charge.
With old types of rechargeable batteries it was a good idea, but more modern NiMH batteries will slowly wear down.
There is not any fixed time limit on how long they can stay in the charger, but it will slowly reducing their lifetime

HKJ said:

Most NiMH chargers does not turn completely off when finished charging, but continues to apply a small current, this is called trickle charge.
With old types of rechargeable batteries it was a good idea, but more modern NiMH batteries will slowly wear down.
There is not any fixed time limit on how long they can stay in the charger, but it will slowly reducing their lifetime

Click to expand...

Thanks for the quick reply. I've been using rechargeable batteries in my high end cameras for years, and I never put them in the charger unless I am going to be home and can take them out fairly soon after they are done charging, but I won't sit there and watch it, so it could be up to an hour, maybe a little more before I take them out. Sounds like an hour or so won't hurt. I do know I am going with some Eneloop batteries, but there are so many chargers out there, and I know so little that it is taking me some time to do the research. I see more negative comments on the NiteCore chargers than on others. How would this charger compare to the Sanyo MQR06?

wingspar said:

Thanks for the quick reply. I've been using rechargeable batteries in my high end cameras for years, and I never put them in the charger unless I am going to be home and can take them out fairly soon after they are done charging, but I won't sit there and watch it, so it could be up to an hour, maybe a little more before I take them out.

Click to expand...

An hour is not a problem, but days is.
When you check my reviews you will also see that there are differences in the trickle charge current, some are down to 10mA, others (like this) uses 100mA. The 10mA is, of course, much better.

wingspar said:

Sounds like an hour or so won't hurt. I do know I am going with some Eneloop batteries, but there are so many chargers out there, and I know so little that it is taking me some time to do the research. I see more negative comments on the NiteCore chargers than on others. How would this charger compare to the Sanyo MQR06?

Click to expand...

I have not tested the Sanyo and do not know how it works.
One reason there may be many negative comments, is because there are many i4 in circulations. There will always be a few bad devices from any manufacturer.
With the old generation there also was the problem with voltage termination, if that voltage is to high, the battery will get hot. This 2014 version is supposed to have -dv/dt termination also, that will prevent most of that.

Thank you for the review, HKJ! These are so helpful for us when choosing a charger.

HKJ said:

An hour is not a problem, but days is.
When you check my reviews you will also see that there are differences in the trickle charge current, some are down to 10mA, others (like this) uses 100mA. The 10mA is, of course, much better.

I have not tested the Sanyo and do not know how it works.
One reason there may be many negative comments, is because there are many i4 in circulations. There will always be a few bad devices from any manufacturer.
With the old generation there also was the problem with voltage termination, if that voltage is to high, the battery will get hot. This 2014 version is supposed to have -dv/dt termination also, that will prevent most of that.

Click to expand...

Thanks for the replies. It helps a lot. I was considering starting a thread on chargers, asking questions about this charger and the Sanyo MQR06. I've been taking notes for a couple of days before starting the thread.

How new is the 2014 version of the NiteCore Intellicharger i4? I've only been able to find the 2014 version on Amazon.

wingspar said:

How new is the 2014 version of the NiteCore Intellicharger i4? I've only been able to find the 2014 version on Amazon.

Click to expand...

I do not know when they released it, but they contacted me late May about the review.

HKJ said:

I do not know when they released it, but they contacted me late May about the review.

Click to expand...

Sounds like it may be too new to be out there widely yet. I found a place that has 10 reviews on the unit between June 26 and July 22 (yesterday). 7 gave it 5 stars, 2 gave it 4 stars and 1 gave it 1 star. Too early for any long time use reviews. $18 seems pretty reasonable. The Maha Powerex MH-C9000 seems like overkill for me. Wouldn't this charger do just as well? I'm trying to keep it simple. Battery terminology is over my head.

wingspar said:

Sounds like it may be too new to be out there widely yet. I found a place that has 10 reviews on the unit between June 26 and July 22 (yesterday). 7 gave it 5 stars, 2 gave it 4 stars and 1 gave it 1 star. Too early for any long time use reviews. $18 seems pretty reasonable. The Maha Powerex MH-C9000 seems like overkill for me. Wouldn't this charger do just as well? I'm trying to keep it simple. Battery terminology is over my head.

Click to expand...

The MAHA cannot charge LiIon, but it can tell you about the conditions of your cells. There are many other chargers with that function, like the BM100 I has just reviewed and it does not cost more than the i4.

The i4 is designed to be a simple charger to use for both LiIon and NiMH cells, it is slow but get the job done.

Thanks for a very comprehensive review! I got a I4 a couple if weeks ago, just checked the box and it says 2014. I didn't know there was a difference, so nice to learn about it.

HKJ said:

The MAHA cannot charge LiIon, but it can tell you about the conditions of your cells. There are many other chargers with that function, like the BM100 I has just reviewed and it does not cost more than the i4.

The i4 is designed to be a simple charger to use for both LiIon and NiMH cells, it is slow but get the job done.

Click to expand...

How slow is slow?

I ordered a bunch of Eneloop AA batteries today. This will be my first foray into rechargeable batteries other than camera batteries. Simple is best for me, so the i4 is looking good to me.

I don't know anything about Li-Ion batteries, (other than my camera batteries that I just stick in the charger that comes with the camera and leave in till the light stops blinking) but the i4 will allow me to keep my options open as I learn about Li-Ion batteries, which I haven't even looked into yet.

wingspar said:

How slow is slow?

Click to expand...

If you look at the charts, you can get the precise time (it is 3 to 6 hours).

HKJ said:

If you look at the charts, you can get the precise time (it is 3 to 6 hours).

Click to expand...

I've read somewhere here on the forum that slow can be better than fast, but there may have been more to what I read than I remember.

I've never timed any of my camera batteries, but sometimes they seem to take a very long time, and sometimes not. Must depend on how depleted they are?

wingspar said:

I've never timed any of my camera batteries, but sometimes they seem to take a very long time, and sometimes not. Must depend on how depleted they are?

Click to expand...

With most chargers the charge time depends on how depleted the battery is.
With NiMH batteries the charger may also miss termination and charge a long time (This is bad for the batteries).

I just ordered the "NITECORE i2 (New 2014 version)" from Amazon, only cost me 16 cents because I had a balance left over from a gift card I earned previously

Being on a tight budget it gave me a chance to get a smart charger after having just regular everyday chargers ! (except for the basic low cost li-ion charger that came with the 14500s, which wasn't a smart charger)

I do occasionally use a 14500 battery for my Coast HP1, but mostly will be using NiMH AA rechargeables for my flashlights.