There are many reasons why you want to discharge LiPo batteries. Maybe you have fully charged LiPo left after a flight session, or maybe you want to discharge the battery completely for disposal. In this article I will show you a few simple ways to discharge your LiPo batteries.
You may use your LiPo chargers to do it since most of them these days have discharging function. But they are normally only rated for a few watts and can take a very long time to discharge.
Further Reading: How to dispose LiPo batteries?
Table of Content
3in1 Battery Discharger
You can get the 3in1 discharger from:
This is one of the fastest and most economic dischargers. At 150W, it can discharge most batteries in a matter of minutes.
You can either discharge the battery completely, or set a voltage to stops the discharge (e.g. 3.80-3.85V per cell for storage). It is simple to use and even keeps all the cells balanced during the discharge.
One thing to watch out for is that the bulbs get really hot during the process. It’s important that you keep them away from anything that can melt or burn. Leave them on concrete floor is perfect.
DIY Light Bulb Discharger
Check out the tutorial: How to build a DIY halogen bulb discharger
This is possibly my favourite way to discharge batteries for disposal. It’s not expensive to make, and it’s a lot faster than using resistors of similar price.
These halogen light bulbs are rated at 12V, so in theory you can only discharge up to 3S batteries. However if you connect two in series you can do up to 6S, and this is what I did in my tutorial.
DIY Resistor Discharger
Check out the tutorial: How to build a DIY resistor discharger.
I really like this DIY tool for discharging old or damaged batteries. It’s cheap to make. Perhaps a bit slower, but it’s much safer for damaged batteries as it won’t build up heat in the battery and cause puffing.
If you have a LiPo charger that can be powered by a LiPo battery, you can do reverse charging :)
Basically you can use your fully charged LiPo to power your charger, and storage-charge your empty LiPo’s. You can even connected multiple fully charged packs on a parallel charging board to speed up the process.
This is a fast and great way to discharge your full LiPo to any voltage you want, and no energy is wasted.
Make sure to set minimum input voltage to 3.8V per cell, for a 4S that’s 15.2V, for a 6S that’s 22.8V. Maybe even slightly lower than that, due to the voltage sag under load, and voltage will normally come back up after resting.
- Jul 2018 – article created
- Mar 2019 – added reverse charging