XTAR recently got in touch with me and sent me a Moon RC2 (which I reviewed here), and a SV2 Rocket charger for a review. I really liked that Moon RC2, so let’s see how this SV2 Rocket does!
Thanks to XTAR for sending these items for review!!
XTAR SV2 Rocket Charger Official Specs:
- Li-ion, Ni-MH, and Ni-Cd charging
- 1.5h to charget two 2500mAh 18650 batteries
- 0.25A for small cells
- LCD screen
- Big slots (fits 10440 to 32650, or AAAA to D size)
- Universal Charger compatible with 10440, 14500, 14650, 16340, 17335, 17500,17670, 18350, 18490, 18500, 18650, 18700, 22650, 25500, 26650, 32650 3.6/3.7V Li-ion/IMR/INR/ICR batteries and AAAA, AAA, AA, A, SC, C, D, Ni-MH/Ni-CD batteries
- 0V Activation Function: Revive “damaged” (low voltage) batteries. Bring your overly discharged batteries back to life
- Cut-Off Voltage: Li-Ion: 4.2V & Ni-MH/Ni-CD: 1.45V
The above section contains the manufacturer’s descriptions and claims, not my impressions or results.
Fast charging well built versatile charger. I’m happy that it does Ni-MH as well as Li-ion – that makes it a charger I can just leave in the house to charge any of my cells!
- Versatility – charges more than just Li-ion
- Charges many sizes
- Fast charging
- LCD display showing charge percentages
- XTAR SV2 Rocket
- Charging cable
- Cigarette lighter cable (!)
Manual and Packaging
The packaging is quite large
but there’s a lot inside there! The back of the box,
much like the XTAR Moon RC2, has a lot of useful information about the product. The sides
are mostly fluff, but still have a fine design.
The manual is one long sheet, that I’ve broken into 4 parts:
there’ll be a little overlap, but you’ll get the idea). The main operation is on pages 5-7 – it’s all very straightforward.
Build Quality, Durability, and Disassembly
The build quality of this unit is fine, but not exceptional. (I’d consider the Nitecore F1 to be exceptional – I believe the terminals on it are gold plated). Still, the SV2 Rocket
is good quality. The slides/springs are pretty smooth. All the plastic parts fit together very well, and are high quality plastic (unlike some other units I’ve reviewed), and the LCD is exceptional
I did have one slight problem – I was inserting a cell, and squeezed the negative terminal almost all the way as far as it’d go. It popped broken. This prompted me to get a closer look at the disassembly of the SV2. I took it apart to see what was broken.
Disassembly is easy. There are 6 rubber “feet”
on the unit. They’re stuck over a hole, under which is a phillips screw. Removing all those screws allowed the SV2 to open easily, and I could see what was broken. The post that holds the spring in place, for the slide/return of the negative terminal, is plastic and had broken. I contacted XTAR about this and they said I was the first to report this problem, and they sent me a replacement unit. They took the serial number of the unit and I believe did a fair amount of internal research to see what might go wrong, and what could be done to prevent this in the future. I’ll add that since I was inside the unit, I took out the broken parts and the other bay of this charger still works as intended. So while it was annoying, it wasn’t catastrophic. And if a user had that problem, I expect XTAR would support you just like it did me, with great customer service.
The SV2 comes with two power cables. One for AC power from the wall, and one to be powered by a cigarette lighter. The wall cable
outputs the needed 12.0V ⎓ 2.0A.
As the max charge amperage of the SV2 is 2A, the SV2 requires the incoming power to be high enough to supply 2A out. Ie you will not be charging at 2A from a small solar cell. Energy ain’t free, yo.
The cord on the wall wart is a bit short – approximately a meter.
User Interface and Operation
There’s one button for the whole operation.
It operates both bays, which can be operated independently. When a cell is inserted, the SV2 immediately begins to check to what “percentage” the cell is charged. From there, clicking the button cycles the choice of charge speed – 0.5A, 1.0A, 2.0A. 0.25A is available too, but that requires a quick double tap on the button. To turn the display off, just hold the button til it turns off (charging will continue). The button is just slightly slow to respond. Just slow enough that a lot of time I think it didn’t register, so I click it again, only to overshoot the A I was aiming for.
I am honestly not sure what exactly is meant by the percentage. A proper analyzing charger will have to go through a few cycles to get a really accurate estimation on what the cells capacity is, and at what stage the cell is toward being “full.” For example, I’ve just tested on the Opus BTC 100 a bunch of laptop pulls. I’ll “charge test” which discharges, and then charges, and tells me how many mAh is put into the cell. Only then do I know what the capacity is.
Furthermore, I’m iffy on how accurate the percentage is. For example, I can remove a cell reading 95% and reinstall it immediately and it’ll read 87%. The unit does seem to spend a few seconds trying to decide what percentage the cell is, and so it does bounce around.
One possibility is that the SV2 estimates percentage based on the voltage of the cell. Battery University is full of great information and what I read there supports my presumption that the SV2 uses cell voltage for the percentage readout. For example, the cell I have beside me now, reads 83%, and I just checked the voltage at 4.03 with a DMM.
There’s also the possibility that the SV2 has a built in load tester, which works how load testers work, and the result is the SV2 telling me a percentage.
Truthfully for me it’s not that important – And I’m probably more of the market this unit is aimed at than a bunch of the really technical guys around here. I find the percentage to be close enough, though I do wish there was at least some more information given. If it was load testing the cells, at least report the associated info to me (for example, cell internal resistance). And it doesn’t seem like a huge leap as technical as it already is, to throw in some mAh reporting as well…. This big blue display is just too nice not do do more!!
Other sources do mention a 100mAh trickle charge, but I was not able to confirm this in the manual or package.
Here’s what charging looks like.
In that image, both cells are charging. Note that only one charge speed can be selected – both cells in this case, being charged at 0.25A.
Once you’ve left the unit alone for a little while (30 seconds or so), it will dim the display
slightly, to what I’d consider a “night-room-safe” brightness. And by holding the button for about a second, the [display can be turned off completely.
I really wish there was a way to set this (or maybe even the dim option as default. Truth be told I’d like the choice to have any option be default – this is an area I believe most chargers could improve….
All of that said, the display on this thing is absolutely fantastic.
The manual states that the SV2 considers battery temperature and won’t over-temp a cell in order to achieve the desired current input. For example if a cell gets too hot when you’ve selected 2.0A, the unit will smartly throttle. I don’t have a way to test that but in my experience with the SV2, cells really didn’t seem to get too hot even at 2.0A anyway.
After charging those two cells pictured (one unprotected 18650, and one protected 16340), the voltages were as follows:
16340: 4.18V (read “100%”)
18650: 4.19V (read “99%” – never went to 100)
For the range of cells this SV2 charges, the size is to be expected. It’ll charged D cells side-by-side…. So it has to be big enough! The LCDs don’t seem to take up too much unnecessary space, so all in all, a reasonably sized charger.
What I like
- Charges many size cells
- Charges multiple chemestries
- Fast charging
- 0.25V charge option
- LCDs switches to lower brightness automatically (unlike nitecore D4) and can be turned off
- Comes with cigarette plug power cable
What I don’t like
- Lack of further info from the very nice LCDs
- No auto switch to 0.5V or 0.25V when cell is nearly full
- Manual could be much more detailed
- LCD can’t be turned to default off
- Competitors can actually charge at 3A
- No powerbank capability
- Can’t set charge rate per-cell
This is a fine little fast charger, and I really appreciate that it supports Ni-MH as well as Li-ion. And the array of sizes it can accommodate as well make it very appealing!
mmmm gurl look at that body