Originally Posted by SoaringDude

. I just posted a review from a local newsletter article I did about this: http://www.f5j-usa.com/article-smart...harger-review/ Hope it helps.


Chris

I haven’t read your review, but that discharger has lots of bad reviews. Seems to like to quit working in just a few uses

Been working great for me and a few others I know. I use it all the time now.

I just picked a ISDT D2 dual port A/C charger, it has discharge as well as storage modes,, gives a wealth of info on its very bright LCD screen, my fav though is it shows resistance of each individual cell when charging, and also tells you when battery is at 90% so you can terminate charging there if you wish

Ps edit : maybe I should start putting my batteries into storage charge when not using for awhile??

Just saw these, smarty quad kids...
https://www.racedayquads.com/collect...ery-discharger

Originally Posted by Bmwjoon

Just saw these, smarty quad kids...
https://www.racedayquads.com/collect...ery-discharger

Thanks for the link!
I ordered and just received a few of them.
Quick shipping, nice web-site and service.
I wish the discharge power was higher.
I will test them at home.

--

Originally Posted by olgol

Thanks for the link!
I ordered and just received a few of them.
Quick shipping, nice web-site and service.
I wish the discharge power was higher.
I will test them at home.

--

Share a little review, I might get some of these as well. Sort of the solution I was looking for. The lower wattage is way safer especially on older packs.

I wonder what's in those things. Could it be just a zener diode and something to limit current, like a resistor?? In that case:

https://www.digikey.com/product-deta...BCT-ND/7899990

They have something smart enough to stop drawing current when storage voltage is reached with a pretty tight voltage tolerance, so I don't think it as simple as a diode and resistor. Looks like many more components on the board.

No 3S XT60 version unfortunately. The XT30 is a bit small for over 35A for me, although I suppose the quad guys push them much harder than that.

I guess a faster discharge rate would make more heat which might not be great for carrying around, and likely would be too much for the tiny surface mount components.

Kevin

The LipoSuction gadgets worked as intended.
One battery I charged slightly above storage voltage (maybe 15.6V). The gadget sucked it down to 15.4V and turned off. Very slowly though, it took a lot of time just for 0.2V.
The second battery I charged up to full voltage 16.8V. The gadget sucked it down to 15.5V on the next day when I checked it after work, and it was off also. So it works as designed.
The circuit board was quite warm when plugged in.
Not sure why they sell the 3D printed covers for the gadgets, and insist on using them. They are blocking heat dissipation IMO. Maybe to protect the fingers from the potential burns. But they do not get hot enough for that.

Are you saying that zener diodes don't have tight enough voltage tolerances? If I understand correctly, they conduct on the order of micro or nanoamps once the critical voltage is reached, so I don't think we have to worry too much about the cutoff.

Originally Posted by kcaldwel

They have something smart enough to stop drawing current when storage voltage is reached with a pretty tight voltage tolerance, so I don't think it as simple as a diode and resistor. Looks like many more components on the board.

No 3S XT60 version unfortunately. The XT30 is a bit small for over 35A for me, although I suppose the quad guys push them much harder than that.

I guess a faster discharge rate would make more heat which might not be great for carrying around, and likely would be too much for the tiny surface mount components.

Kevin

Why not just use the "storage charge" function built into most better chargers these days---if the pack voltage is high it gets discharged---if low it is charged---and ends up getting balanced in the process.

Steve

Originally Posted by lincoln

Are you saying that zener diodes don't have tight enough voltage tolerances? If I understand correctly, they conduct on the order of micro or nanoamps once the critical voltage is reached, so I don't think we have to worry too much about the cutoff.

If I read this data sheet correctly (possibly not!), a Zener you might use for a 3S battery (PDVZ 10B) with a desired storage voltage of 11.1V, has a range from 10.0V to 11.2V. The next one up has a range from 11.0V to 12.3V.

I guess that coresponds with the stated tolerance of +/-5.58%. That would be about 1.2V at 11V.

Maybe there are ones with tighter ranges?


Kevin

There are some which are tighter, though I'd argue even the one you mentioned is better than no discharge. How about this one?:
https://www.digikey.com/product-deta...ICT-ND/3451586

Originally Posted by Airman74

I just picked a ISDT D2 dual port A/C charger, it has discharge as well as storage modes,, gives a wealth of info on its very bright LCD screen, my fav though is it shows resistance of each individual cell when charging, and also tells you when battery is at 90% so you can terminate charging there if you wish

Ps edit : maybe I should start putting my batteries into storage charge when not using for awhile??

I grabbed one of these 10 months ago, loved it, until it died. Now getting support has been really hard, they sent me a replacement PCB which I had to replace myself. After a short runtime the new PCB blew the display. I am waiting to hear back, hoping they just send out a complete new unit as I don't want to continue swapping parts...

Tom

Originally Posted by tporter416

I grabbed one of these 10 months ago, loved it, until it died. Now getting support has been really hard, they sent me a replacement PCB which I had to replace myself. After a short runtime the new PCB blew the display. I am waiting to hear back, hoping they just send out a complete new unit as I don't want to continue swapping parts...

Tom

Yikes!!! Hope mine keeps working