[Review] Nitecore UM2 (2 slides, Li-ion, Ni-Mh, IMR, USB, microUSB, charge indicators)

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[Review] Nitecore UM2 (2 slides, Li-ion, Ni-Mh, IMR, USB, microUSB, charge indicators)

Hello to everyone laughing
Thanking them for the trust, today we will review the UM2 which was kindly provided by Nitecore itself.

CLICK HERE to go to the official product page on the Nitecore website.

I want to clarify that my reviews are made at an amateur level, so without the aid of science fiction tools or tests in secret laboratories and cutting edge. Therefore, among the lines that follow, there will be my humble observations and even my humble opinions.

Official features:

- intelligent USB dual-slot charger
- QC 2.0 input available
- capable of charging 2 batteries simultaneously and controlling each slot independently
- up to 1.500 mA charging speed in a single slot
- compatible with Li-Ion and Ni-Mh/Ni-Cd batteries with automatic detection
- automatic detection of battery power level anda automatic selection of the appropriate voltage and charging mode (LiFePO4 and 3,8 V Li-Ion batteries excluded)
- automatic selection between 3 charging modes (CC, Cv and -dV/dt)
- energy-efficient LCD display for real-time charging information
- capable of manually selecting the charging cut-off voltage and the charging current
- automatic detection of large/small capacity batteries and automatic selection of appropriate charging current
- automatic termination upon charging completion
- reverse polarity protection and short circuit protection
- over-discharfed battery activation
-  Li-Ion battery restoration
- overtime charging protection
- made from durable and fire-retardant PC materials
- optimal heat dissipation design
- certified by RoHS, Ce, FCC and CEC
- insured worldwide by Ping An insurance )Group) Company of China, Ltd.

Where to buy it

The Nitecore LC10 (when available) could be purchased from NitecoreStore.com

The packaging

I received the UM2 as a preview from Nitecore but it was sent to me without the packaging.

The only things I have received are:
- the UM2
- a USB-> microUSB cable just over 75 cm long

Most likely, only the multilingual manual and the warranty card are been added to the packages for sale.

A detail of the USB / microUSB plugs of the cable.

Here is the manual in the English and Italian languages only. You can view (and download) the entire manual at THIS address.

The charger

The UM2 is a new multichimic charger (able to accept both Ni-Mh and Li-Ion / IMR / LiFePO4) of Nitecore and is able to accommodate even the long 21700 protected. The charger body is built with the usual plastic material able to delay the flames.
The charger, like other high-end products of Nitecore, has a generous screen at the top (backlit but which will turn off automatically after 10 minutes of inactivity to save energy), two keys with which you can change some settings and 2 independent slides able to recharge well 2 different batteries at a maximum speed of 1500 mA per channel when you will power it with a power supply (not included in the package) with fast charging because the UM2 is compatible with the QC 2.0.

As I said before, under the screen there are 2 keys marked with a C and a V. With them we can recall the various information of one or the other channel and, when needed, change the settings as the cut-off voltage of Li-Ion batteries (automatically detects those at 4.2 V) or adjust the charging speed.
Between the two keys we find the name of the charger.

Immediately below are the two slides. On the plastic is engraved the design of a battery with + and -, just to remind to the user the polarity to be respected.

I also add a photo of the two positive contacts

and of the two negatives.

Both slides run smoothly and do not have any jamming. Their minimum extension is 2.94 cm and maximum of 7.8 / 7.9 cm, enough to accommodate many types of batteries.
Note that the Nitecore logo is engraved on the slide.

To power everything, you need of just a simple USB-> microUSB cable (included in the package) that will be attached to the corresponding port on the top of the charger. Also note the presence of deep fins that help to dissipate any heat produced.

On the opposite side, on the bottom, stand the Nitecore logo.

Looking sideways at the product, next to the screen, there are other dissipating fins. They are not very pronounced like those on the side of the USB port, but they have very small openings that let go out the heat generated by the electronic components placed inside.

In the back there are various information about the accepted batteries and data on the inputs and outputs. The CE, RoHS and FCC certifications are not to be missed.

Here below there are in detail the various types of batteries accepted:
- IMR / Li-Ion / LiFePO4: 10440, 14500, 14650, 16500, 16340 (RCR123), 16650, 17350, 17500, 17650, 17670, 17700, 18350, 18490, 18500, 18650, 18700, 20700, 21700, 22500, 22650, 25500, 26500, 26650, 26700
- Ni-Mh / Ni-Cd: AA, AAA, AAAA, C, D

We can then recharge from the small AAAA / 16340 up to the longest 21700 or 26700 wide, so that they are Ni-Mh or Ni-Cd as they are Li-Ion (including the powerful IMR) or LiFePO4 thanks to the fact that the UM2 is a multichymic charger.

At the bottom of everything, under other holes that improve ventilation, there is a yellow sticker on which it is specified that the UM2 has an input of 5V or 9V (at 2A), depending on whether or not we will use a power supply with the QC 2.0, and an output (always if we use a QC 2.0 power supply) of 1.5A per channel, for a total of 3A.

How does it work

The UM2 can be powered by any wall or car USB power supply but to be able to use its maximum power (and therefore reach 1.5A per channel) it is necessary to use a power supply with fast charge because this charger is compatible with QC 2.0 (if you use 3.0, nothing will change).
If you do not physically dispose of a power supply at least QC 2.0 but a common power supply that delivers 5V and 1A (therefore less than 2A required) you can use however the charger but the maximum speed that we can set on the single channel will be lower and will be divided between the 2 channels if we insert 2 batteries.
Doing this will increase the charging time.

The UM2 will communicate to us, thanks to a writing that appears at the top right of the display, whether or not we are taking advantage of the quick charge.

In detail the above mentioned writing when we will power the UM2 with 5V and 2A

and with a QC 2.0 power supply capable of delivering 9V and 2A (those required to operate at maximum). In the second case, the phrase "Quick Charge" will appears on the screen.

We have seen in the previous chapter that the charger has 2 keys, with the left one (C) you can switch from one channel to another to see how the recharging process proceeds. An arrow will also help us to quickly identify the selected channel. Because it is a multi-channel battery charger with independent channels, we can also simultaneously charge 2 different chemistry batteries at different speeds.

In this case on the 1st channel (Slot 1) I'm loading a Ni-Mh

while, in the second (Slot 2) I'm loading a Li-Ion.

As I said before, the charger will automatically detect if a Ni-Mh or a Li-Ion (4.2V) is been inserted on the slides but if you insert a battery with a different cut-off voltage it will may be necessary to manually set the charging parameters.
Nothing difficult. Once the battery/ies has been inserted, press C to go to the desired slot and keep pressed C again to enter the settings. Once done, the charging speed or the area concerning the cut-off voltages will start to flash. Press C will make us switch from one to the other setting. In the case of cut-off voltages, V will change the settings making us choose between 4.2V, 3.7V (LiFePO4) or 4.3V.

If we are in the recharge speed settings, with V we can instead select a speed between 100 mA and 1500 mA (with 100 mA steps) for each channel.
NW In automatic mode the UM2 detects even if the battery is more or less small in capacity, automatically setting a preset speed. 500 mA for small and 1000 mA for large.

Once the voltage and the desired speed has been selected, all that remains things is to hold down C to save the settings, insert the battery and wait that the charging process come to the end. Meanwhile, we can check how the recharge proceeds by observing the information on the screen. In fact, we can see the charging speed, the voltage at which the battery is,

the mAh charged and from what time it is charging.

Here is a table with the various recharging times I found on some cells at certain speeds.
Batteries used: nominal 5000 mAh 21700, nominal 4500 mAh 26650, nominal 3500 mAh 18650, nominal 750 mAh 18350 and nominal 1900 mAh Ni-Mh AA.

In case that we insert batteries in reverse polarity or we have a dead or with the PCB blocked cells, it may happen that the message "EE EE" starts to flash on the screen. In this case, if we are sure that the battery has not been inserted in reverse and we want to restore the battery, we can hold down the V key to start the Restoration Mode that will test the battery, restore it and start the charging process.

The batteries in the sleds

I take this opportunity and also take some pictures to show how some batteries fit in the slides of the UM2.

Here is a AAA and AA Ni-Mh,

a 18350 and a 14500,

a 26650 and a 18650 (2x26650 would enter without problems)

and 2x21700, one protected (SX) and one unprotected (DX).

Dimensions: weights and dimensions

The Nitecore UM2 measures 15.1 x 7.34 x 4 cm and weighs 148 gr.

Next here there is the dimensional comparison with a big BIC lighter and a 18650,

with a 20,000 mAh powerbank,

with the Nitecore SC4,

with the Opus BT-C3100,

and with the XTAR SV2.

Here is a video to show you in detail the charger and how the information is shown on the display

Personal considerations

The UM2 confirm the quality of Nitecore products. Even the compatibility with the new and large 21700 protected batteries is guaranteed.
The two independent channels and the high recharge speed are 2 excellent qualities, you have only to remember that it requires a fast power supply to operate at the maximum of its possibilities.
The space between the two sleds can accommodate even 2x26650 side by side, 2x21700 protected and with the recovery mode you can even think to restore dead or with the PCB locked
This UM2, for what it offers, is a great charger for all the users that looking for a great product but with that something extra that the automatic battery chargers do not offer. Those looking for something more professional and with more features should turn to look to other products.
The only flaws found are that during recharging, as also happens with the big brother SC4, you can hear a little "coil whine"(or noise) but does not affect the operation of the product and that you have to pay attention to the recharging of the smallest batteries (14500/16340) because can happen that, by inserting them in a hurry, they can not touch the poles well.
Overall, however, I would like to reiterate that it is a good product and therefore promoted to me.

What do you think of this UM2? Would you buy it?