Test/review of Charger NiteCore UM4

HKJ

Flashaholic
Joined
Mar 26, 2008
Messages
9,715
Location
Copenhagen, Denmark
[size=+3]Charger NiteCore UM4[/size]

DSC_4055.jpg


This is a USB QC powered 4 cell universal charger with adjustable current.

DSC_4056.jpg
DSC_4057.jpg




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

DSC_4050.jpg


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

DSC_4058.jpg


The charger has the USB connection on the back together with a plastic heat sink.

DSC_4060.jpg


The charger has two switches:
C: A short press will change slot and longer press will enter the charge and battery menu.
V: Step between displayed values and change settings in menu.

DSC_4192.jpg
DSC_4193.jpg

DSC_4194.jpg


When charging it will show chemistry (Li-ion), algorithm (CV), charged capacity, internal resistance, current, voltage and time.
The "Quick Charge" is present when the charger is power from a QC charger.

DSC_4196.jpg
DSC_4198.jpg


The charger supports 4.30V, this will undercharge 4.35V batteries slightly. LiFePO4 is shown as 3.7V and NiMH is shown as NiMH/NiCd with -dv/dt algorithm.

DSC_4197.jpg


Error.



The yellow label has the important specifications and is easy to read.

DSC_4061.jpg
DSC_4062.jpg


The slots uses the usual construction and works well. They can handle batteries from 30mm to 79.8 mm long, the new 21700 with protection will fit in the charger.

supportedBatteryTypes.png


supportedBatterySizes.png


DSC_4280.jpg
DSC_4281.jpg
DSC_4282.jpg
DSC_4283.jpg


DSC_4286.jpg
DSC_4287.jpg
DSC_4284.jpg
DSC_4285.jpg

DSC_4288.jpg
DSC_4289.jpg
DSC_4290.jpg
DSC_4291.jpg


The charger can handle 79.8 mm long batteries, inclusive flat top cells.



[size=+2]Measurements[/size]


  • Discharges LiIon with 0.3mA and NiMH with 0.06mA when not connected to power
  • Below 0.8 volt the charger will show EE and charge with about 1mA.
  • At 0.8 volt the charger will assume NiMH and start charging.
  • The charger will assume NiMH below 1.8 volt and LiIon above 2.0 volt.
  • Will not restart if battery voltage drops.
  • Charges with 0.05mA when LiIon battery is full.
  • Voltmeter readout freezes when charging is finished
  • Voltmeter is within 0.02 volt.
  • Change between 0.5A and 1A is around 56mm long batteries.
  • Charger uses 9V in QC mode and up to 2A current.
  • Charge will restart charging after power loss or battery insertion.
  • Slot #1 and #3 share a charge circuit.
  • Slot #2 and #4 share a charge circuit.
  • Power consumption from USB when idle without batteries is 35mA


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

Current can be adjusted from 0.3A to 1.5A in 0.1A step. Default is 1A with long batteries and 0.5A with short batteries.

Nitecore%20UM4%201A%20%28SA18650-33%29%20%231.png


This is a nice CC/CV charge curve with about 150mA termination current.
Display shows 2820mAh, 3:38, 232mOhm

Nitecore%20UM4%201A%20%28SA18650-33%29%20%232.png

Nitecore%20UM4%201A%20%28SA18650-33%29%20%233.png

Nitecore%20UM4%201A%20%28SA18650-33%29%20%234.png


The 3 other slots are similar, but there is a minor voltage difference.
Display shows 2907mAh, 3:44, 210mOhm for #2
Display shows 2815mAh, 3:54, 110mOhm for #3
Display shows 2847mAh, 3:51, 202mOhm for #4

Nitecore%20UM4%201A%20%28SA18650-26%29%20%231.png

Nitecore%20UM4%201A%20%28PA18650-31%29%20%231.png


The two other capacities are also charged fine.
Display shows 2350mAh, 2:58, 163mOhm and 2610mAh, 3:25, 152mOhm

Nitecore%20UM4%201A%20%28BE18650-26%29%20%231.png


This old cell is handled fine.
Display shows 1794mAh, 3:44, 500mOhm

Nitecore%20UM4%201.5A%20%28AP18650-26%29%20%231.png

Nitecore%20UM4%201.5A%20%28SA18650-33%29%20%231.png

Nitecore%20UM4%201.5A%20%28SA20700-30%29%20%231.png


Increasing charge current to 1.5A works without problems.
Display shows 2628mAh, 2:17, 176mOhm for AP18650
Display shows 3076mAh, 2:57, 161mOhm for SA18650
Display shows 2918mAh, 2:15, 112mOhm for SA20700

Nitecore%20UM4%200.5A%20%28SA18650-33%29%20%231.png


A lower current also works fine, but with the same termination current.
Display shows 2778mAh, 6:05, 258mOhm

Nitecore%20UM4%200.3A%20%28AW18350-IMR%29%20%231.png


This old and worn down cell I charged at lowest setting., the charger works fine, but a lower termination current would have worked better.
Display shows 116mAh, 0:32, 375mOhm

Nitecore%20UM4%200.5A%20%28KP14500-08%29%20%231.png


A 14500 with 0.5A charge current works, but again a lower termination current would have been better. The termination is also at the minimum voltage.
Display shows 604mAh, 1:39, 500mOhm

Nitecore%20UM4%201.5A%20QC%20%28AP18650-26%29%20%231.png


Boosting input voltage to the charger with QC do not make single cell charging faster.
Display shows 2640mAh, 2:08, 157mOhm

Nitecore%20UM4%200.5A%20%284xSA18650-33%29.png


With four cells in the charger the current is reduced to 0.5A for each cell.
Display shows 2966mAh, 6:56, 126mOhm for #1
Display shows 2880mAh, 6:38, 117mOhm for #2
Display shows 2896mAh, 6:55, 128mOhm for #3
Display shows 3003mAh, 6:47, 94mOhm for #4

Nitecore%20UMS4%202A%20QC%20%284xSA18650-33%29.png


With QC power the charge speed is faster, in this case around 1½ hour is saved.
Display shows 3101mAh, 5:31, 164mOhm for #1
Display shows 3016mAh, 5:13, 111mOhm for #2
Display shows 3038mAh, 5:29, 120mOhm for #3
Display shows 3028mAh, 5:13, 167mOhm for #4

Nitecore%20UM4%201A%200.5ohm%20%284xSA18650-33%29.png


Using a 0.5ohm resistor in series with 5V power to simulate a weak charger or long cable makes the charger real slow, but it will charge the batteries.
Display shows 2712mAh, 19:22, 223mOhm on #1
Display shows 2672mAh, 18:02, 146mOhm on #1
Display shows 2581mAh, 19:23, 229mOhm on #1
Display shows 2704mAh, 17:46, 123mOhm on #1

Temp6360.png


M1: 41.5°C, M2: 43.1°C, M3: 42.9°C, M4: 42.1°C, M5: 45.8°C, HS1: 51.9°C

Temp6361.png


M1: 48.4°C, HS1: 52.9°C

PoweronLiIon.png


The charger need some time to start a charge. The charger measured voltage with current off.

PoweronLiIonQC.png


Using QC do not change much, the charger is a bit faster to start, probably because the QC request is answered.

Charge1%2B3LiIon.png


The charger will timeshare the charging circuit when multiple slots are used, this means average charge current is halved.

CurrentChangeLiIon.png


When entering the current change menu the current is turned off and first resumed when leaving the menu.

Charge%20Solar%20LiIon.png


The charger has a small problem with a unstable power supply.



[size=+1]4.30V LiIon charging[/size]

Nitecore%20UM4%201A%20%28LG18650-30%29%20%231.png


The charger charges fine to 3.0V, but most "high voltage" batteries are 4.35V and they will be undercharged slightly.
Display shows 2564mAh, 3:10, 236mOhm



[size=+1]IFR (LiFePO4) charging[/size]

Nitecore%20UM4%200.5A%20%28SO14500-LiFePO4%29%20%231.png


Display shows 439mAh, 1:05, 560mOhm

Nitecore%20UM4%201A%20%2818650-LiFePO4%29%20%231.png


LiFePO4 is charged fine.
Display shows 1104mAh, 1:25, 185mOhm



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

Current can be adjusted from 0.1A to 1A in 0.1A step both with USB and QC power supplies. Default is 0.5A

Nitecore%20UM4%201A%20%28eneloop%29%20%231.png


This is a nice -dv/dt charge curve with a very short top-off at the end (Only a few minutes).
Display shows 1706mAh, 1:47, 480mOhm

Nitecore%20UM4%201A%20%28eneloop%29%20%232.png

Nitecore%20UM4%201A%20%28eneloop%29%20%233.png

Nitecore%20UM4%201A%20%28eneloop%29%20%234.png


The 3 other channels looks similar.
Display shows 1986mAh, 1:52, 423mOhm on #2
Display shows 1748mAh, 1:49, 500mOhm on #3
Display shows 1740mAh, 1:49, 263mOhm on #4

Nitecore%20UM4%201A%20%28eneloopPro%29%20%231.png

Nitecore%20UM4%201A%20%28leise25%29%20%231.png


The two high capacity cells are also handled nicely.
Display shows 2506mAh, 2:36, 500mOhm for Pro
Display shows 2581mAh, 2:41, 142mOhm for Leise

Nitecore%20UM4%200.5A%20%28eneloop%29%20%231.png


Termination works fine at 0.5A charge current on AA.
Display shows 1748mAh, 3:38, 464mOhm

Nitecore%20UM4%200.5A%20%28eneloopAAA%29%20%231.png


This makes it easy to charge a AAA battery.
Display shows 714mAh, 1:30, 500mOhm

Nitecore%20UM4%201A%20full%20%28eneloop%29%20%231.png


A full cell is detected in about 10 minutes, this is fairly fast for a -dv/dt charger.
Display shows 139mAh, 0:10, 197mOhm

Nitecore%20UM4%201.5A%20%28eneloop%29%20%231.png


The 1.5A charging also wors fine.
Display shows 1898mAh, 1:19, 223mOhm

Nitecore%20UM4%201.5A%20%284xeneloop%29.png


With four batteries I may select 1.5A, but the actual current will be around 0.75A
Display shows 1923mAh, 2:43, 480mOhm on #1
Display shows 1815mAh, 2:34, 266mOhm on #2
Display shows 1932mAh, 2:43, 187mOhm on #3
Display shows 1965mAh, 2:39, 204mOhm on #4

Nitecore%20UM4%201.5A%20QC%20%284xeneloop%29.png


There is no bonus for using a QC power supply here.
Display shows 1798mAh, 2:32, 313mOhm
Display shows 1898mAh, 2:40, 177mOhm
Display shows 1956mAh, 2:39, 208mOhm
Display shows 1940mAh, 2:42, 209mOhm

Temp6373.png


M1: 46.2°C, M2: 48.2°C, M3: 48.3°C, M4: 47.2°C, M5: 50.8°C, HS1: 66.2°C

Temp6374.png


HS1: 63.9°C

PoweronNiMH.png


The charger needs some seconds to initialize before it will start charging.

PoweronNiMHQC.png


Using QC do not change it.

Charge1%2B3NiMH.png


The charger will timeshare the charging circuit when multiple slots are used, this means average charge current is halved.


CurrentChangeNiMH.png


Charging is turned off while adjusting current.

Charge%20Solar%20NiMH.png


Unstable power supply do not work perfectly with NiMH either.



[size=+2]Internal resistance[/size]

The internal resistance measurement is not very impressive on this charger.

RiLiIon.png


This is for LiIon

RiNiMH.png


And NiMH.
Some of the readings are probably correct, but there are to many sporadic readings.



[size=+2]Conclusion[/size]

The charger works well with good default LiIon currents, it is possible to select a lower or higher current with some button presses. There is also the detail about time sharing, this means with 3 or 4 batteries in the charger the current is reduced.
The internal resistance measurement do not work very well.

I will rate the charger as good.



[size=+2]Notes[/size]

The charger was supplied by a Nitecore for review.

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

tripplec

Enlightened
Joined
Jun 2, 2013
Messages
397
Location
Belleville, Ontario
This an other USB chargers from Nitecore don't come with a power supply. So what did you use that supplied the required input high current needed. I was looking at a UMS4 last week on their site and on the internet and its the same situation. Also this charger appears to run very hot especially at the power input of the USB-C connect. How long it would last would be a concern. Although you mentioned the stat on temperature you did not comment on it.
 
Last edited:

HKJ

Flashaholic
Joined
Mar 26, 2008
Messages
9,715
Location
Copenhagen, Denmark
This an other USB chargers from Nitecore don't come with a power supply. So what did you use that supplied the required input high current needed. I was looking at a UMS4 last week on their site and on the internet and its the same situation. Also this charger appears to run very hot especially at the power input of the USB-C connect. How long it would last would be a concern. Although you mentioned the stat on temperature you did not comment on it.

I used a lab power supply for 5V and a Blitzwolf BW-S9 for QC testing. I do seldom comment on temperature when it stays below 50°C on the batteries, the electronic inside the charger may also be 70-90°C hot without any problems (Some parts are rated for 150°C). A significant part of the inside temperature will often show up on the battery connections pads and a USB connector, because they have good thermal contact to the circuit board.
 

tripplec

Enlightened
Joined
Jun 2, 2013
Messages
397
Location
Belleville, Ontario
Thats too hot for my liking but its personal. As for these charge ports for the power supply. What does Nitecore expect the owner to use with them. I would never use a C enabled computer to power it even if its rate around that. Stand alone power supply is not even offer as an accessory in the listing they have. The SC4 appears to be their only viable charger although the display doesn't seem as good.
 

richard13

Newly Enlightened
Joined
Feb 15, 2015
Messages
10
From the screenshot it looks like it comes with a standard Type-A USB to micro USB cable. You should be able to just plug this into a typical USB port on your computer.
 

HKJ

Flashaholic
Joined
Mar 26, 2008
Messages
9,715
Location
Copenhagen, Denmark
From the screenshot it looks like it comes with a standard Type-A USB to micro USB cable. You should be able to just plug this into a typical USB port on your computer.

That is not a good idea, the charger needs more power than a typical computer USB port can deliver.
 

tripplec

Enlightened
Joined
Jun 2, 2013
Messages
397
Location
Belleville, Ontario
From the screenshot it looks like it comes with a standard Type-A USB to micro USB cable. You should be able to just plug this into a typical USB port on your computer.

Don't ever do that. Its an almost sure way to blow the port in your computer, then what, warranty? I doubt it you'll fry the motherboard. It isn't safe computer accessories made to plug in are engineered to communicate with it and the port managing power.

You want and need an external PS and it would have to be one of substantially higher current at the sustained high load for the charge cycle.

As HKJ has already said and I have mentioned this before in another thread I am sure.
 

mlankton

Newly Enlightened
Joined
Feb 15, 2020
Messages
1
the display on the UM4 doesn't sleep? I just got this and as near as I can tell the display never shuts off like the D4 does. Is this correct? I don't like that.
 

alexbigmac

Newly Enlightened
Joined
Dec 5, 2020
Messages
1
Good afternoon, everyone.
I bought a Nitecore UMS4 charger to be used with a QC 2.0 mainly to charge 3 Molicel P42A 21700.
I've read extensively reviews and tests to many different chargers and this one seemed like the best in this price range to charge these batteries.
The only thing that I haven't fully understood is how does the timeshare work and what are the implications of it.
I read the manual available online and as far as I understood, the charger has 4 slots for charging the batteries but in reality 2 charging circuits – one for slots 1 and 3 and another for slots 2 and 4, efectively timesharing the charging between each slot.
As far as I understood, the charger charges at 2×2A (QC) / 2×1A (USB) alternating between each slot every 10s, ie., charges slot 1 at 2A during 10s and then charges slot 3 at 2A during 10s, efectively averaging 1A in each slot, and the same happens with the other slots. Is this correct?
Is the only drawback that instead of charging at 1A constant it charges at 2A every 10s and, once the charging phase switches from CC to CV, it actually reduces the average current? After all, once the charger begins charging at constant voltage, the current that the battery can take is reduced. And since it charges at, for example, 1,5A every 10s in each slot, the average current is 0,75A when it could be charged at 1A constantly without interruptions.
So, while the charger is at the CC phase, it is no different in charging time but once it reaches the CV, the charging time is actually increased. Am I thinking correctly?
Also, if one inserts two batteries at different charge levels in slots 1 and 3, for example, they can't be charged at the same current. How does the charge handle this situation? When it switches slots it also changes the current?
What are the drawbacks and advantages of this charging method?
I'm sorry for the long post but this is kind of complicated and I'm hoping someone could explain this to me since this charging method is new to me.
Cheers!



 
Last edited by a moderator:

sbj

Newly Enlightened
Joined
Feb 19, 2017
Messages
172
......... So, while the charger is at the CC phase, it is no different in charging time but once it reaches the CV, the charging time is actually increased. Am I thinking correctly?...
I think yes

......... Also, if one inserts two batteries at different charge levels in slots 1 and 3, for example, they can't be charged at the same current. How does the charge handle this situation? When it switches slots it also changes the current?...
It'll do it that way.

.........What are the drawbacks and advantages of this charging method?
I'm sorry for the long post but this is kind of complicated and I'm hoping someone could explain this to me since this charging method is new to me.
Cheers!
For the user, I don't see any advantage, rather a slight disadvantage, if all four slots are used, as you already recognized when charging during the CV phase.

For the manufacturer he has the advantage, that he saves two charging circuits and can still advertise the charger as a fast charger with four charging slots.:eek:
 
Top