Solved Shorted my lipo battery balance plug for a split second & some more questions

I shorted my lipo battery(1300mah, 3s, 45C) balance plug for a split second and some smoke came out but the lipo was still useable & chargeable. However I noticed that the 2nd cell was kind of weird… My multimeter(https://www.amazon.com/gp/product/B07RNPHJN6/?tag=lstir-20) said it was at 3.78 volts then 3.5volts then 3.75volts then 3.6volts then like 1.3volts and then showed cell 3 at like 6 volts and then back to around 3.76 volts. My other cells are at 3.815 volts and their voltage doesn't jump around that much only by like 0.002. Is the 2nd cell damaged? Also since I shorted my balance plug could that cause the C rating of my battery to go down?

I am going to retire that battery soon once I get enough money to buy another one...
 

CarolineTyler

Legendary member
I shorted my lipo battery(1300mah, 3s, 45C) balance plug for a split second and some smoke came out but the lipo was still useable & chargeable. However I noticed that the 2nd cell was kind of weird… My multimeter(https://www.amazon.com/gp/product/B07RNPHJN6/?tag=lstir-20) said it was at 3.78 volts then 3.5volts then 3.75volts then 3.6volts then like 1.3volts and then showed cell 3 at like 6 volts and then back to around 3.76 volts. My other cells are at 3.815 volts and their voltage doesn't jump around that much only by like 0.002. Is the 2nd cell damaged? Also since I shorted my balance plug could that cause the C rating of my battery to go down?

I am going to retire that battery soon once I get enough money to buy another one...
Sounds like you damaged the balance lead rather than the battery. If the main voltage stays solid but one cell shows off changing readings then it's the balance wire to that cell that is burnt up a bit.
Unless you're really good at soldering and have some kaptan tape to re-insulate the cells you could open up the pack and replace the balance lead. I would not advise it though.
 

Indy durtdigger

Elite member
Damaged battery = discharge and proper disposal of it. Or risk a Lipo fire and any collateral it takes with it when it goes up.
 

Bricks

Master member
I agree with @CarolineTyler, most likely damaged the balance lead not the cells. It’s your choice to make the repair or replace.


Have to agree I have taken 2 bad Lipos and made one good one out of them, soldering to the tabs is the hardest part if thee are tabs still left.
 

PsyBorg

Wake up! Time to fly!
If you are newer to the hobby or new to soldering the safest thing is drain and recycle the battery. I would not advise modifying or repair unless you are fully confident in your abilities. The risk to your safety and or house due to fire if done wrong is significant vs the cost of a lipo.
 
If you are newer to the hobby or new to soldering the safest thing is drain and recycle the battery. I would not advise modifying or repair unless you are fully confident in your abilities. The risk to your safety and or house due to fire if done wrong is significant vs the cost of a lipo.
Would the battery still be useable if only the balance lead is broken?
 
Yes. But it will go out of balance as you charge/discharge it and that can cause performance issues and may cause excess heat build-up in the battery - potential fire hazard!

Oh I see :( what kind of performance issues? I kind of want to get another battery but they are really expensive.
 

CarolineTyler

Legendary member
Oh I see :( what kind of performance issues? I kind of want to get another battery but they are really expensive.
When a cell is out of balance it creates a resistive load within the battery. Any sort of resistance in the battery reduces the amount of power the battery can supply and the difference is turned to heat in the battery. That's why most pilots balance charge their batteries.
 

PsyBorg

Wake up! Time to fly!
You can replace the connectors easily enough. You can find balance connector replacements with wires so all you do is splice them in. No need to open the pack. Getting a pack too far out of balance is one of the things that make them explode on the charger since the charger has no reference it charges to max voltage and you end up with over charged cells to compensate for under charged then POOF!!
 
You can replace the connectors easily enough. You can find balance connector replacements with wires so all you do is splice them in. No need to open the pack. Getting a pack too far out of balance is one of the things that make them explode on the charger since the charger has no reference it charges to max voltage and you end up with over charged cells to compensate for under charged then POOF!!

Oh I just gave up and the battery is now in a salt water bath right now
 

PsyBorg

Wake up! Time to fly!
Take it out... salt water bath does nothing but erode the contacts off. the charge potential remains. Drain it off using a light bulb or a dc motor.

 
Take it out... salt water bath does nothing but erode the contacts off. the charge potential remains. Drain it off using a light bulb or a dc motor.

Uhhh I'm probably going to leave it in the salt water bath for a week, clean it to make it safe and dispose of it at my local Home Depot… Idk why I did the salt bath in the first place but I guess I may as well do it.