Review: XTAR DRAGON VP4 Plus Charger

Instead of rereading the whole review what is the charge % anomaly?

If they design the charger why not give it on the side where the plugs are external aluminium fins with 4x4x7cm
Or design parts of the body from aluminium for cooling

That would be fine to get enough heat dissipated for 4 times 2A discharge current

They design the plasic body to look as it cools, but it is useless

It could be designed like this home media PC

I actually like both brands. I have a couple of Xtr VC2's and recently got the smaller Opus BT-C100. My only complaint for the Xtar's is they don't seem to like charging 14500 cells. You have to get them in just right. The Opus I'm still experimenting with. It does seem to take a very long time testing quality 18650's. I do like the option of 1.6 Amp charging if I need one on the run.

I would still purchase either brand at the right price.

I will add a couple of things. Not seeing voltage would stop my buying if it is a charger designed for testing cells. However, even with on screen voltage once I remove a cell showing full at say 4.2. They never meter at that. I have more DMM's than I can keep up with and all get a reading of closer to 4.1. On the flip side I attribute this to using the standard leads that any given DMM came with. So I'm probably easily loosing that tiny amount due to the length of the lead wire.

Either way excellent review. Adding video was a great touch.

That as 1% charge is somewhere in the region of 3V (exact figure unknown) that the charger shows 1% for quite some time when discharging, which is done to 2.6V. A test yesterday saw around 400mAh discharged from a 2 protected GAs whilst on 1%.

yikes, thats crazy, i have not tested any discharging on this charger, just charging of various brands of li ion and NiMH cells.
When i first tried it i like the percent charge but having used it a few times i realized voltage is far superior, and i realized the percent can never be perfected in a one size fits all solution :frowning:

I would agree, too many idiosyncrasies for the % charge to be truly useful. Though, it would not stop me recommending this otherwise excellent charger. As mentioned in my review, I would much prefer voltage reading, and the bar graph graphic for approximate % full indication.

Have you noticed that chargers with digital readouts of charged voltage does not stop charging right away when 4.20v appears? My Opus and my iCharger shows that.

It’s because even if the voltage show 4.20v, I observed that about one-fourth of the mAh energy pumped into the cell is still in this stage, so while the voltage stays at 4.20v, you will notice that mAh is still pumped in while the ma or the rate of the charging slowly goes down to 1/10th of the chosen charging rate, eventually filling up the cell and showing Done or Full.

In others words, when 4.20v shows, we don’t take the cell out right away but still wait for the charger to detect a ‘full’ cell.

In short, a charger with voltage readout has no inherent advantage over a percentage one because we still have to wait ‘Full’ or ‘Done’ or the green led to show for a fully-charged cell.

This is part of the constant current/constant voltage algorithm. When the battery voltage reaches 4.2V the charger switches to constant voltage mode and starts reducing the current until the termination point in order to fully charge the battery.

Yes, I know, and that’s my point, no real worry or agrument to whether it’s percentage or voltage, since we still have to wait for the CC stage to drop to 1/10th for the charger to terminate, even if the CV, whether in percentage (100%) or the 4.20v has just showed, as it’s not yet truly full.

It boils down to personal preference between digital readout or percentage.

They can improve the percentage algorithm, but they can’t get it perfect for one size fits all. For example 1.24V NiMH read 0, 0 is actually 0.9-1.0V not 1.24V (which is about 75% on the batteries i tested)

Even if they changed % to be somewhere more realistic such as 1V, the discharge in test and refresh modes goes down to 0.85V, so there would be still be 01% displayed for a quite a while on discharge (note: when on discharge the % charge never goes to 00%).

My Lacrosse BC700 considers 0.9V to be empty, i don’t know how much energy there is between 0.9-1.0V but i can live with 0.9V as the cutoff point. Like i said there is no perfect one size fits all here, but i bet we agree that 1.25V is not empty.

If you have voltage and current reading then it is easier to see where you are. Once the 4.2V CV is reached you can watch the current drop. I’m sure Xtar have been suggested this but they don’t seem to listen unfortunately.

This is an old review. But I still found this review quite useful. Thanks to the author for posting his views in such clear to understand and helpful manner. He also covered several points of public interest which many reviews do not.

Thanks. The charger is still going well! Very reliable workhorse!

I am on the lookout for a 4-bay Li-ion + NiMH charger-cum-analyzer that has a discharge voltage termination set at or below 2.8V preferably.

Even better if the termination point can be determined & set by the user (above 2.55V for safety reasons.)

Are there any other such 4-bay chargers since 2016 when you wrote this review? I can’t seem to find any.

I also wonder at what voltage level the Miboxer C4-12A terminates its discharging cycle. This info isn’t easy to come by.

Does this Xtar unit allow for setting a target voltage like the SkyRC MC3000 does? Like say I want to charge a li-ion 18650 cell up to 4.1 instead of 4.2. Can I do this?

It does not.

Even after reading this review I still prefer the Opus BT C34100 v2.2 over this one. I like having individual slot controls. The only one I see better is the Charger SkyRC MC3000 but that is above my budget. The Opus at $50 right now is a super deal compared to this one with better control and the fan.

Does not seem like many battery charger changes in the last few years is there anything in this mid-range that you consider better than the Opus at this time?

I think it depends on your need and personal taste.

The Vapcell S4+ is also a good charger for LiIon and NiMH

Personal I´m not pleased with Xtar since I have the VC4SL, so I avoid to buy this brand again.