Horses for courses and all that. I understand if people want a do-it-all charger but some don’t mind.
I infact prefer excellent dedicated chargers like the Maha that’s makes no excuses for its limited applications. I’d happily take a 18650 only charger that’s as good as the Maha is at AA’s.
Fact is the most common battery is the 18650 so if it’s only good for that, it’s not a problem but it should be stated.
Ferongr, I don’t think the USB supply (2.4A USBs are everywhere now and cheap) is a problem for a well designed two bay charger, it’s not like the terrible implementation of the Xtar VC4. Seems strange to complain the supply is too weak and then in the same paragraph complain the charge current is too high!
Let’s see what HKJ finds eventually or hope someone else can at least check termination in the mean time. Does it trickle at the end, discharge the cell or restart the charge?
Edit: nice input Ian, did you check the USB voltage at full load, perhaps it is sensitive like the Xtar. Maybe stick a power supply on the USB input instead and see if you keep it at the USB max standard ,5.25V iirc, that it still can only do an Amp per bay?
Interestingly enough the post above you states problems charging both slots at full speed with 5V USB. The problem is that the USB A connector is not designed for such high current. Just a bit of resistance in the connector will create a big voltage drop due to the high current, and with the low voltage, the real power reaching the charger is a lot lower. Furthermore, it’s not only current output that matters, but also voltage under load from the adapter, many of them drop below 5V at higher currents, causing another drop in output power.
I just added that in an edit reply after I saw Ian’s post. I suggest a power supply to see if this is the case, it’s a known issue with the Xtar. If it’s still a problem then efficiency may not be great I guess?
Two Li-Ions with a 4.2V termination with a charge current of 1.5A will require 12.6W of power to maintain constant charge current until the CV phase. A 5V, 2.4A adapter can only supply 12W of power in theory. With many of them that is an unattainable goal as they drop below 5V at those currents. Furthermore, the switching converter inside the charger itself will waste some power by itself. Assuming a very efficient converter with 90% efficiency, an adapter that maintants 5V and no losses in the USB connector and cable, you;’re left with 10.8W to use. Real life figures will probably be lower.
The more I look at the notes that I have made the more I think something is weird so I am going to test some more cells tomorrow but I am also going to test the same cells on a couple of other analysing chargers I have to compare with them also so my review will probably not be done till the weekend.
The USB supply I used is an ORICO 30 watt 5v supply, 2.4A max per outlet (I have tested this & can confirm it to be correct) & 6A total over the 4 outlets if they are all being used.
HKJ rates this USB supply as being good.
I tried a cheap 12v 2A supply I have but that I know to be good & 2 of my Lii-500, 12v 2A supplies.
All 3 12v 2A supplies allowed both bays to charge at 1.5A each.
I also have a Blitzwolf 5v 4.8A 24 watt 2 output USB & I will try that as well.
I will put my USB tester inline & see what is going on
There is a hollow plug to USB cable and a car adapter with 12/5V 2A output included
So you can pretty much connect most 12V power supplies to this charger which is good
They put at least that car adapter to the charger, XTAR and others come just with a cable, and its not bad having a 5/12V capable USB car adapter
The charger is designed to deliver max output when connecting a new USB wall supply which has 12V output as well
Nowhere does the charger state Qualcomm Quickcharge or USB-PD compliance, and I don’t think it has the necessary chip that is required to switch those adapters into higher voltages.
Ferongr, check HKJ reviews, protection on many kicks way over 2.4A for lots of quality USB supplies.
Check this Ravpower, 2.4A is tickling it, 11A protection, 8A continuos no problem at all… HKJ Ravpower test
The Anker uses individual output protection but still does over 3A… HKJ Anker review
Those aren’t cherry picked USB chargers, they are the bestseller manufacturers on Amazon.
With that once you finish CC the current drops away so you are not drawing 1.5A at 4.2V anyway. Many supplies can also maintain voltage no problem, my blitzwolf has triggered the OVP on my DP tech USB monitors before. It maybe pushing the limits but not much and nothing compared to Xtar putting a 4 bay on USB supply!
At that point, the charger is out of the USB spec and using it is inadvisable as you cannot be certain the power supply or USB connector will cope. I could discharge my NCR18650Bs at 15A too, but I’d gamble their condition and my safety.
I discharged an Efest 16340 (3.28v), and it settles in charging at .75A. No heat either. Must be some way this charger is sensing the cell’s ability to take a charge? Looking forward to what other’s have to say who own this charger.
Well I have put the pair of Basen 26650”s back in after discharging them down to 3.6v & am using my ORICO 5v 2.4A USB supply again this time with a USB meter in line.
So far, just over 2 hours into charging the cells are being charged at 0.45A each & the USB meter is showing 0.89A so pretty close.
Voltage reading on the USB meter is 5.04v & has been constant since the charging started.
Charger says there is about 2 hours 20 minutes to go on the cells.
I will note the highest charging current & the voltage & then when this has finished I will try the 12v supply again with the 26650”s after again discharging them & see what current it charges at.
You are just trying to argue now, as I’m sure you know, nearly everything is out of spec now, Apple/Samsung do it on every product nearly, 0.5A is the max allowed by traditional USB, see Wiki… USB Spec
No problem running more power, look at newer specs and they will do 5A, type C with the smaller connector is rated to 3A as it starts out.
Cell comparison is irrelevant argument.
We obviously have different opinions here. I would like to see a well implemented USB powered 2bay charger, you think it’s unsuitable, that’s fine. I like the 12V ability too, so be it if that’s the only way to get higher charging rates but the USB input I would personally find useful.
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Ian, thanks for posting results, doesn’t look promising at the minute then, what a shame.
Cells are up to 4.14v each now & the charger is saying 42 minutes charge left.
The highest charge currents I have seen is 0.50A & 0.55A, confirmed by my USB meter showing 1.04A draw.
The meter has shown the voltage between 5.01v-5.04v for the whole charge cycle & has not dropped below 5.01v.
When I used the 12v power supply both these cells were charged at 1.5A each as the manual states.
Without the USB meter I was seeing 1.0A per channel now it is only aeound 0.5-0.55A ?
When I put the cells into the charger they were at 3.68v each so I assume should have had about half their measured by me 4300-4400mah capacity.
This means they needed around 2000ma to reach full charge.
The charger showed a charge time of 4 hours 30minutes when the cells were put in which would be in line with 0.5A charging rate (4.5 x 0.5A =2250ma).
As opposed to 1.5A charge rate which would have charged the cells up in around 1.5 hours so should have shown a charge time of around 1 hours 30 minutes.
The cells are now fully charged & came off the charger, immediately tested as soon as it said FULL, at 4.188v & 4.189v.
The highest charge current I saw was 0.55A & voltage from the USB supply was between 5.01-5.04 all charge.
I am now discharging the cells & will take them down to 3.68v each, so as to compare, & do another charge using a 12v 2A supply.
