First of all yes I know the only right way to discharge a lipo is to fly it.  

But sometimes it can happen that due to bad weather or stress at work and or with the family and so on, you have full lipos and now you have to find a way to unload, and I finally found a solution that seems good to me and that for less than 25dollars!
This will be an ongoing tutorial, so this is only the first try and I will update it as often as possible.

Video of the tool and how the mod is built and works.

1. Description of the Tool URUAV Lipo Killer Discharger
2. How to Hack/Improve the Discharge time – Description
3. What to you need for the mod
3a. How to Build
4. Danger and Saefty
5. How to Discharge a Lipo Battery for disposal

1. Description of the Tool URUAV Lipo Killer Discharger

So let’s start this little tool the URUAVUR4 Lipo Killer Discharger

You can find it on Banggod link for about $6.80 in flash deal for the next few days.

The tool has two functions, the XT60 on the right is a 0 Volt Discharger this is useful for half-dead lipos after a crash and you want to discharge this 0 before you can put it in the trash. (it takes about 24 hours)

The balance plug on the other side is the 4.0 to 3.0 Volt Balance Discharger 1-6S.
Yes, you read correctly that it balances the cells and this is one of the great advantages compared to other dischargers on the market.
Another advantage is that once the URUAVUR Lipo Discharger reaches the final discharge voltage, it automatically shuts down without fan noise.

Here a short description from Banggood

Usage Instruction:
0V Discharger– Plug your battery’s XT60 Connector in the yellow connector ( on the right side of board)- Then 0V LED will keep lighting untill finishing dischager- 0V LED Light goes off, which points at battery dischager to 0V.- Discharging to 0V need 24 hours above4.0V-3.0V Discharger Balancer– Plug your battery’s balance pin head in the Pin connector ( On the left side of boaed )  

Notice: The battery’s black cable points at “ G“ ( The word showed on the board)
DONT plug in opposite side.- Then this lipo killer will test how many cells of your battery and counterpart LED will light on.  1S-6S Discharge LED will keep light. ( The lighting LED Number depends on your battery’s Cell)- Press “ Set „ button to set the voltage you want to discharge. ( 3/ 3.2/ 3.4/ 3.6/ 3.8/ 4V Optional)  Notice: The voltage you set must lower than your battery’s present voltage- 1S-6S Discharge LED goes off while finishing discharging- Discharging from 4.2V to 3.8V need about 5 hours ( take example as 1300mAh Lipo Battery)
As you can see above from a full 1300mha Lipo to 3,8 Storage it took around 5 hours (this is really long)
In my own tests, it took longer and depends on the mAh from Lipo more mAh more time.
But the best part is that the Tool discharge full automatic to the set Volt and then turn off and this balanced on all leads from 1 to 6S and that is really great.

2. How to Hack/Improve the Discharge time – Description

According to the description it takes about 5 hours and more for
larger lipos and that’s not really fast, safe and without noise, but not
fast, so I was looking for a solution to shorten the discharge time.
That’s why I looked at how this tool works, I saw that the resistors on
the bottom of the tool are separated for all 6 wires, always two of
them. From my other discharge projects in the past I know that I can use
lamps (G4 sockets and lamps) to improve the speed, but this time the
discharge channels are switched on and off with electronics, so we have
to be careful that the lamps don’t overload the electronics, it worked
with up to 10W lamps without any problems in my previous tests. 

Video Link

With 10 Watt G4 lamps I have discharged a 1550mhA Lipo from 100% to
below 20% (3.6Volt) in about 2 hours (you can see this in the video)
with 5 Watt lamps, it took about 3 hours (also in the video). So we can
say for the normal 3.8v memory voltage that it takes about an hour and a
half or less with a 1550mhA Lipo and that’s a nice speed, isn’t it?

3. What to you need for the mod

one (or more) URUAV UR4 Lipo Killer Discharger Bangood Link

6x G4 Lamps 5 to 10 Watt 12 V (10x Lamps in Package) https://amzn.to/2UYwYlD

6x G4 Keramik Sockets with leads (5x Socket in the Package) https://amzn.to/2I2vvr5

Optional my Designed 3D Printed frame thingverse Link https://www.thingiverse.com/thing:3522226

With the Packages from Amazon, you can build one 6S and one 4S Discharger or two 4S and one 2S and so on.

3a. How to Build

To build it is very easy and is shown in the Video around 4:38.
As described above, there are always two resistors in a row. (left to right)

for one cell of your battery, the lamps leads will soldiers on both sides of the two resistors.

Then install the lamps and finish.

For each cell of your battery, the lamp leads are soldered to one end of the resistors.

Then plug in the lamps and you’re done.

With the 3D printing it looks like this, but the design is not finally a work in progress any more better ideas are welcome!

4. Danger and Saefty

First of all, take care of your lipos and always check them for
damage, always keep an eye on the lipos and this tool and never leave
them alone in the room.

ATTENTION THE LAMPS GET VERY HOT, DO NOT TOUCH!

Use a smoke detector!

5. How to Discharge a Lipo Battery for disposal

There are other ways but at the moment this is one of the easiest ways I found to Discharge a lipo to Disposal Voltage.

Most of the current charger can Discharge a lipo but mostyl only with a view watt/h and it takes forever to finish

There is also a Discharger from ISDT (I have on here) this was also
great but I realy get anoyed by the small fan the noise is realy loud.

6. Updates and whats next

I tested this tool now for over 3 Weeks with around 45 lipos from
2S to 6S what I Looking now is can it handle safe 15 or 20Watt lamps
(this will boost the time) but what also has to considert the Balance
leads from the lipos are only good for a view amps so more testing has
to be done.

What I found is when lamps has higher Watts the drifft of the
voltage regulatet is getting bigger maybe I can mod the hardware to make
that less.

I also working on an Datasheet where I but in my Discharge times
but this is in earlier not finished status so please give me time

:)

Thanks for reading hope you like this tool and the mod and you can get a use out of that.