Phantom Battery Discharger Mode 3.85v /50% ?

[dazultra]

Hopefully some more tech savvy people out there can help me on this?

I've just purchased a phantom battery discharger from bangood.com
TMS Battery Discharger 3-6S 12V Light Bulb For DJI Phantom 2/3 DJI Inspire1

When i use it in mode 1, it discharges the battery to 3.8v, apparently this is fine to prevent the battery swelling up when stored for long periods according to bangood.

According to Dji, I need to store the battery with 40-50% capacity when storing it
Phantom 2-Preparing the Flight Battery - DJI Wiki

After using the discharger in mode 1 and I check how much charge is left, my batteries show 75% (3 Lights flashing). So I've been switching to mode 2 to drain further and watching the batteries as they discharge to 50% (only 2 lights flashing), this means I have to keep an eye on it for ages, which doesn't seem right to me.

My question is, is the discharge to 3.8v fine, and my extra discharge unnecessary?
Or is there a better solution out there that I'm unaware of, I don't want to risk more expensive batteries getting ruined.

Thanks for your help!

 

[Mark The Droner]

Haha... I have exactly the same discharger you do.

Discharging to a good storage level isn't something we do often. But once in a while we need to bring a battery down for whatever reason.

Personally I am not comfortable leaving the battery at the storage level where the discharger leaves it. It tends to shut down at 65-70% which isn't low enough in my opinion. I've even noticed a slight swelling in one of my batteries that I left in the 65-70% range. So now I take it down past 50%. So yeah, I hit the mode 2 button and take it down a little more just like you do. I always set a timer for 17 minutes so I don't forget to stop the deep discharge. After 17 minutes the timer beeps reminding me to disconnect the discharger. This brings my battery down to 40-50%.

 

[dazultra]

Why didn't I think of that! Sometimes I would forget and let it run too far, a timer is a great idea, definitely makes it less painful. Awesome thanks!

 

[dirtybum]

That discharger rules i'm goin to pick me up one!

 

[DroneGolfer]

Where would you get one of these for a P2 battery.?

 

[Mark The Droner]

phantom 2 battery discharger | eBay

 

[DroneGolfer]

Thanks so much!

 

[Sparkywest]

I have this one from Amazon, it works great.
Crazepony® Intelligent Battery Discharger for 3-6S Lithium Battery DJI Phantom 2

Here is a link.
Amazon.com : Crazepony® Intelligent Battery Discharger for 3-6S Lithium Battery DJI Phantom 2 : Camera & Photo