Introduction: How to Save a 7s Battery With One Dead Cell?

By GensTattu
About: I'm a UAV player, I attention most news about UAV, And I know much about UAV or UAV accessories, like batteries, cameras, motor and so on

This article is mainly tell you how to save your Lipo battery with one dead cell.

Lipo batteries are also used for RC cars or drones, and it is very popular in some RC car or FPV races. High voltage battery can offer high speed for your rc cars or drones, but what to do to a 7s pack with one dead cell?

Notice: Don't do this if you don't know what you are doing. Very dangerous.
Before these, we should know some basic Lipo batteries knowledge; as we know, a LiPo cell has a nominal voltage of 3.7V, and a lipo cell = 1 cell = 1S = 3.7V. For the 25.9V battery above, that means that there are four cells in series (which means the voltage gets added together). This is sometimes why you will hear people talk about a “7S” battery pack – it means that there are 7cells in Series. So a four-cell (7S) pack is 25.9V, a three-cell (3S) pack is 11.1V, and so on.

So I had a 7s lipo that got one dead cell...
1v after constant 10 hours doing charging and dischargin...I gave up..she's dead.

I will use these 7S Lipo battery to make one 4S batteryand one 2S battery(of course I can make two3S batteries or one6S battery)

Step 1: So What to Do?

Decided to remove the dead cell and make 2 lipos... one 4s and a 2s pack.

  1. Removed the balance plugs with a pin, and put the right ones on a new 2s balance plug...and going to do the same for the new 4s lipo to!
  2. And wire everything correctly for a 4s and 2s packs... The warped in plastic is the dead one...was showin 0,2v now... lol
  3. Taged and warped the others to know what they are.
  4. Now I have a 2s pack for new new build Exo Terra from Axial :P, and a 4s for the Xray 808e SCT, or whatever comes up...And don't need to trow into the right dumpster a lipo.

At last, you must noticed this again: make sure it's dangerous and people need to know what lipos are and what they are doing. If not... don't do it! I do it cause i have "experience" and know what i am doing in RC stuff!

Step 2: