The XTAR VC4S charger was sent to me directly from XTAR for review.

For product features and technical data: www.xtar.cc/charger/vcseries/2019/0430/411.html
Main features of the XTAR VC4S:
• See clearly what is happening with the batteries
• Broadly compatible
• Quick charge QC3.0, Max 3A for each slot
• Try the actual battery capacity, maximize battery life
• Micro USB input, charge anywhere
• Intelligent detection to save time
• Automatically detects the type of battery
• Multiple protections guarantee safe charging
• High precision, auto-off when fully charged
• Activation "0V", restores excessively discharged batteries
Specifications:
Model: VC4S
Entry: QC3.0 (5V-3A / 9V-2A)
Constant current: 3Ax1 / 2Ax2 / 1Ax4 / 0.5Ax4
Automatic charge interruption (Voltage): 4.2 ± 0.05V / 1.45 ± 0.1V
Automatic charge interruption (Amperage): =120 mA
Use Temperature: 0-40 ° C
Dimensions: length 149 mm x width 115 mm x height 35 mm
Weight: 212 grams
Compatible with 3.6 V / 3.7 V Li-ion / IMR / INR / ICR batteries:
10440 14500 14650 16340 17335 17500 17670 18350 18490 18500 18650 18700 20700 21700 22650 25500 26650 32650.
1.2VNi-MH / Ni-CD: AAAA / AAA / AA / A / SC / C / D
Note: 20700/21700 protected batteries cannot be charged.

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The Packaging:
The XTAR VC4S came in a white cardboard box. On the four sides of the box are highlighted, in 5 European languages, the main characteristics that distinguish the new XTAR VC4S charger.
The photo of the XTAR VC4S with the product name, connection type (USB), display (LCD) and supported battery type (Li-ion, Ni-MH) stands out earlier.
Later, other basic product features are listed.


On the two sides of the box we find other XTAR VC4S information such as battery compatibility.

Once the box is open we find chargers and accessories in a foldable gray plastic bag (Hop-pocket), with the “XTAR” logo printed on it, useful for transport.
Inside are present:
- XTAR VC4S
- Micro USB cable
- Manual


The USB/Micro USB cable, present in the package, is 80 cm long and has the writing "XTAR" on the USB connector and the 2.5A writing on the MicroUSB one. The USB connector has the classic orange color that distinguishes compatibility with the QC3.0 fast charge protocol.


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The XTAR VC4S Charger:
After the release of the VC2S battery charger, the XTAR presents the version with four charging stations, namely the VC4S.
With the XTAR VC4S, we can charge batteries of various types and sizes such as Li-ion / IMR / INR / ICR (3.6V / 3.7V) and Ni-MH / Ni-CD (1.2V).
The XTAR VC4S supports the QC3.0 protocol and provides a maximum of 3A for each individual charging slot. It is equipped with a large color LCD screen that displays the charge status in real time and has protection against short circuit, overload and overheating. It is made of fire-resistant ABS material. It is also possible, with the VC4S, to reactivate excessively discharged low voltage batteries.
Below the display we find two keys, with a clearly audible click. The left button with the word "Disp." above is used for switching the display to: Capacity, Current and Internal resistance, while the right one with the word "Mode" above is used to choose the modes that are: Charging, Evaluation and Storing.


Laterally we find openings to dissipate the heat produced during the exercise.

The sleight where the batteries to be recharged are placed, have a smooth run and the right resistance. The two side compartments (CH1 and CH4) can accommodate large batteries, such as the 32650 Li-ion batteries, with a diameter of up to 32 mm, while in the two central units (CH2 and CH3) I managed to get both a 21700 and a 18650 simultaneously. All the compartments are possible, as written in the specifications, also recharge 20700 or 21700 (but unprotected) batteries with lengths up to 70mm.


The XTAR VC4S charger is equipped with a Micro USB input (QC3.0), compatible with USB adapters, Power bank and Solar energy.

Also in the rear part of the XTAR VC4S we find openings, on almost the entire width of the charger, which help to dispose of the heat thanks to 6 rubber feet that slightly raise the VC4S and give stability avoiding slipping.
The lower part shows the plate data and a white label with the XTAR identification data.


Operation:
The XTAR VC4S charger has three operating modes that can be selected with the right "Mode" button:
1 - Charging Mode. In this case it recognizes the type of battery and is adjusted by setting everything automatically.
2 - Evaluation Mode (Grading Mode) to have the effective capacity of the battery through a process of charging, discharging and recharging the battery.
3 - Storage Mode (Store) in case you need to store the battery at a nominal voltage (1.2V o 3.7V) to safeguard its duration if it is not used for a long period.
Let's see the behavior of the XTAR VC4S with the Charging Mode:
Once the USB/Micro USB cable is connected to a compatible power source (it can also be the classic cell phone power supply) and to the battery charger, the VC4S display turns on in stand-by, showing CH1, CH2 , CH3 and CH4 in green which correspond to the four available channels.
Meaning of the LED indicator colors:
Green: stand-by / fully charged / evaluation or storage process terminated.
Red: auto-exam / charge / activation.

The display shows four circles, resembling clock dials, which show the battery voltage (0V to 4.2V - blue part) and the charging current (0.5A to 3.0A - in blue).
Above these circles we have a small blue writing that indicates, in charging mode, capacity (CAP), current (CUR) or internal resistance (IR), while below we have the indication of the charging mA and the type of battery chemistry ( Li-ion or Ni-ME).
When using the QC3.0 adapter, inserting a battery, if its internal resistance is low enough, the recharge will be at the maximum of 3A. If we charge two batteries at the same time then it will be 2A per battery. If the adapter does not support QC3.0 fast charge, the charging current will be 2Ax1 for single battery and 1Ax2 for two batteries.
Let's try to see what changes once a battery is inserted (in this case a 18650 Li-ion battery with adapter QC3.0).
The XTAR VC4S automatically recognizes the type of battery inserted and adjusts accordingly, in this case setting a maximum charge of 3A. We see that the light indicator of the channel used becomes red (CH4). Then we see on the display the indication, in real time, of the battery voltage and the set charging speed (3A), we then have the indication of the type of battery chemistry (Li-ion). With this charger it is not possible to manually set the charge speed (mAh).
Changing, with the "Disp." button, the information displayed, we read other data such as the mAh loaded and the internal resistance of the battery (mΩ).



At the end of the charge the display shows the word FULL alternating with the charge current which results at 0 mA, moreover the luminous indicator of the channel (CH4) becomes green.


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We see the indications on the display by inserting a battery of different chemistry, in this case a 1.2V Ni-MH AA.
In this case we have a variation of the scale on the circular indication which will now be from 0V to 1.55V, and the word Ni-MH which identifies the chemistry of the battery. I'm doing other tests, but it happens that if I charge low resistance AA batteries the charger sets the charge at 2A.
I just hope it's an error on the display but it's not real.



Finally we see the initial indications of the XTAR VC4S display when we are in Evaluation Mode (Grading Mode) and at the end when the display flashes showing the word "donE" and the battery capacity found.




...... and in Storage Mode (Store).


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The XTAR VC4S with the four slots occupied by four different sized batteries:
from left: 16340, AA, 18650 and 21700 (unprotected).

Conclusions:
Good performance of the XTAR VC4S charger, simple to use, versatile and fast. With this charger we can recharge a cell quickly to a maximum of 3A thanks to the compatibility with the Quick Charge 3.0 protocol. Too bad there is no possibility to choose the charging speed in case you prefer to manually set the mAh to be charged. From the tests made in these days I have found that the speed regulation depends in particular on the internal resistance of the battery.
In addition to the standard recharge, we also have the possibility of evaluating and storing the battery obtaining information on the actual capacity of the battery and bringing it to a nominal voltage, for its protection, in case it is not used for a long period or for safety in transport case.
The XTAR VC4S also has the 0V activation function to restore excessively discharged batteries.
In conclusion, a charger with multiple functions recommended, in particular, for those who need a fast tool with automatic settings.
Thank you for reading the review.
