You’ll need a fan for that. Not that I’m against adding a fan. Just sayin
For LiIon sure, for NiMH not. At least I have some chargers which allow discharge of 4x 1A like Keeppower L4, Powerex MH-C9000(Pro)
I think a charger with size of VP4 Plus Dragon should allow to discharge 4x 0,75A with LiIon, at least LiitoKala Lii-600 can do it, Vapcell S4+ can also do 3A with LiIon, 2x1A and 2x0,5A
Never doubt it.
But the most Xtar LiIon 1,5V-charger are not really chargers, more power supplies, the charge electronic is in the cells, not in the “charger”. Only MX4 and new L4/L8 (juest see it on Xtar-page without much info) can charge 1,5V LiIon and also some other chemistries, and it´s all very basic chargers, not analyzers.
And I´m talking about existing chargers which are able to discharge (via Grad, e.g. VC4SL, VP4 Plus, VC8S)
VC8S and VP4L Plus are very new and don´t charge 1,5V LiIon
Xtar still don´t give us details, did they want to modify existing chargers or build a new one with discharging?
BTW, most competitors offer discharge function in many cheaper chargers
It has aluminum heatsinks for each of the 1A slots and temperature sensors on all 4 of them tho. And it still gets too hot without a fan.
*(I accidentally edited this post thinking I was typing a reply to the post below lol. Whoops. I think I put it back to how it was)
Dunno, used max. the 2x 1A discharge for LiIon. Yes, for me it get´s to warm if I compare with the charging, but I don´t think it gets hot.
In the Lii-600 I used max 2x 750mA and 1x 500mA for LiIon, in this case I would say the temp is harmless.
And the VP4 Plus is bigger than these chargers, I guess with a good pasive cooling concept the 4x 750mA should work
Well, you might have better A/C than I do, but I think it gets too hot. The owner’s manual tells you to avoid full load on all 4 slots for too long, I think that’s somewhat telling.
What temperature would you say is hot? I’ve got a temp gun and cells I don’t care about, I’ll see where I can get it lol
In this case more than 50° Celsius is hot, measured with an infrarot thermometer. And I rarely discharge LiIon, with NiMH is no hot problem 
Temp here depends on the seasons 
1 Thank
Agreed, 45°C-50°C is a good max for cells to avoid really accelerated cell aging. I can accept 70°C for external temps for a plastic-cased device (won’t burn skin) as long as the highest internal temp isn’t much higher.
So much depends on where the temp is being measured, the thermal resistance of the path from the heat source to where the heat is being measured, and whether it’s the charger or the cell being measured.
If the temp is measured at 50°C*** but it has dropped by 100°C from the heat source to where it’s being measured (high thermal resistance path) then there is a big problem. If reading the heat source directly = 50°C then all is good.
The outside temp of a plastic-cased device can easily be 100°C lower than the junction temp of the hot components of a charger’s power supply or discharge circuitry. I’ve measured that, and worse, in chargers I’ve tested.
***making sure that 100% of the IR gun’s FOV is within the tiny area you want to measure.
2 Thanks
Overall it´s hard to measure, I drift very slow over the cells and take a look at the max. temp.
The temp in the charger itself I can´t measure exactly, if I insert small cells I can maybe measure between the cells but it´s maybe not the place where are the discharge-resistors are located.
I hope the charger-designer and technicans test if their chargers are made for the max. discharge-current
1 Thank
I have the Vapcell S4+ and use all its functions. I want even more settings. Specifically, I want to:
- charge, setting current and max voltage
- discharge, setting current and min voltage
- grade, setting current and min voltage.
- storage - optional (if charge/discharge have max/min voltage)
You used all slots, max. discharge rate?
Xtar asked about the discharge function, can´t imagine they want to design a completely new charger.
Even if I hope they bring a charger with functions all other manufacturer already have 
1 Thank
Yeppers
OK, that will generate more heat than my 2x 1A
I don´t think it´s not critical for the cells, but in a passive cooled charger it´s getting very hot
Do you plan a new charger with discharge, current setting or you want to modify an existing charger which have already testing function?
Thanks for the comment. We are still working on it. If modifying the existing xtar chargers, which one and features you prefer?
1 Thank
I would vote for the VP4(L) Plus Dragon.
Because:
- IMHO it´s the best Xtar-charger
- it already has the possibility to discharge via “Test”
- the frame size should make the heat distribution easier than with a smaller housing…
- … and because of this I think it would be possible to add higher discharge rate like 4x 0,75A or 2x1A + 2x 0,5A for LiIon and 4x 1-1,5A for NiMH without active cooling
But a new charger in that/similar size with some other features would also welcome
- individual slot settings
- voltage display instead of %
- some details for all slots, maybe with auto-switching like Skyrc or via button
2 Thanks
Good list 
With this features it would be a very interesting charger I would buy instantly if not absoluty overpriced.
I know some chargers which have some or most of the features but not all.
Edit: Please don´t use the VC4SL for it, the NiMH-charge is to bad for me to buy it again, even it would have such features
I would also like (and be willing to pay for) a discharge function. Also, the ability to set the discharge current. For example, I do a lot of location sound recording, and the recorder I use is powered by 8 AA batteries. It draws a lot of power when I have 8 microphones. I would like to be able to test various batteries to see how long they will last in practical use in the field, when recording. So, I need to be able to discharge at 1200 ma to duplicat actual field conditions. I am not aware of any 8-bay analyzer/charger that provides that functionality.
Also, rather than have two separate 4-bay chargers that are packaged together, I would suggest to have an 8 bay charger that acts as a single charger. For example, it should be able to grade all 8 slots in one go. (Not just 4 slots at a time.)
Also, I’d like to see a charger that can charge at .5C in all 8 slots. For 2700mah AA batteries, that would be 1300 or 1400 ma. For AA NIMH batteries that power requirement is well within the capability of a 45W power supply. (500ma, UNADJUSTABLE, is just too little for a 2700mah AA NIMH cell!)
Thank you.
Regards,
DG
This is very good functionality to have. I use it quite a bit on my MC3000. I would welcome it on a less expensive charger.
A storage function that discharges to about 3.7 volts is great.
One that can be configurable to stop at a user assigned voltage, even better. I like to test cell capacity in accordance with the data sheets. These do have varying specifications for the lowest termination voltage and the current to use on discharge. So, good to be able to adjust these parameters.