lipo balance problem

[dolby]

It looks like I might have a faulty battery.
I just did a charge on one of my packs (just a regular charge 5amps) and noticed that as it was charging there was a difference of 0.5 volt between the highest and lowest cell. I then stopped the charging process immediately and went to do a balance charge. After about 5 minutes I got an error message "battery voltage - cell high vol'. I checked the cell voltages and they are:
C1-4.15 ,C2-2.53, C3-5.00, C4-4.13, C5-4.16, C6-4.13

It looks like cell 2 is dead. I see no puffing from the pack. Is this pack a throw away? Should I discharge the pack since cell 3 looks very high?

(moderator edit: merged your duplicate thread in another forum with your original. One thread per topic please.)

 

[dolby]

It looks like I might have a faulty battery.
I just did a charge on one of my packs (just a regular charge 5amps) and noticed that as it was charging there was a difference of 0.5 volt between the highest and lowest cell. I then stopped the charging process immediately and went to do a balance charge. After about 5 minutes I got an error message "battery voltage - cell high vol'. I checked the cell voltages and they are:
C1-4.15 ,C2-2.53, C3-5.00, C4-4.13, C5-4.16, C6-4.13

It looks like cell 2 is dead. I see no puffing from the pack. Is this pack a throw away? Should I discharge the pack since cell 3 looks very high?

(moderator edit: merged your duplicate thread in another forum with your original. One thread per topic please.)

 

[dolby]

It looks like I might have a faulty battery.
I just did a charge on one of my packs (just a regular charge 5amps) and noticed that as it was charging there was a difference of 0.5 volt between the highest and lowest cell. I then stopped the charging process immediately and went to do a balance charge. After about 5 minutes I got an error message "battery voltage - cell high vol'. I checked the cell voltages and they are:
C1-4.15 ,C2-2.53, C3-5.00, C4-4.13, C5-4.16, C6-4.13

It looks like cell 2 is dead. I see no puffing from the pack. Is this pack a throw away? Should I discharge the pack since cell 3 looks very high?

(moderator edit: merged your THIRD duplicate thread in another forum with your original. One thread per topic please. Do not continue posting new identical topics every few minutes! Be patient and wait for someone to be able to reply to you!)

 

[dogman dan]

I would define the very low cell, and the very high cell as too damaged to be safe anymore. Cell 2 and cell 5 break the lipo rules. The other three cells could be salvaged.

Edit, cells 2 and 3. Not cell five, the one at five volts.

 

[2moto]

How does cell 5 break the LiPo rules? Did you mean cell 3?

 

[dnmun]

yep, typo. since they are adjacent i bet it is a loose balance lead inside. he started three threads and vanished.

 

[dolby]

Interesting now I have had the same problem charging my last pack. Exact same error message on the charger with the virtually the same cell voltages. C2 : 2.42v and c3 : 5.00v. Maybe I have a prob with my charger?

 

[dnmun]

if that happened to a different pack, then it is your charger. you should actually measure them directly since the charger voltmeter may not be accurate.

 

[dolby]

if that happened to a different pack, then it is your charger. you should actually measure them directly since the charger voltmeter may not be accurate.

You are correct! I turned the charger power off and on and now all cells are balanced again. I wonder if it is safe to charge now?

 

[dnmun]

so you don't have a voltmeter?

 

[dolby]

Yes I do but I don't want to cut open the packs since they are only a week old and would void any warranty.

 

[dnmun]

you don't have to cut them open if they have balance leads. you can measure the voltage at the plug on the balance leads. did you ever use that balancing charger before this?

 

[dolby]

you don't have to cut them open if they have balance leads. you can measure the voltage at the plug on the balance leads. did you ever use that balancing charger before this?

Ok I will measure across balance leads. I have been using this balance charger for the last week.

 

[dogman dan]

Duhh, I'll go edit that.

The too high, and too low cell have each become dangerous. I'm not saying unusable, just dangerous to use.

Oh, and before you tear the whole pack apart, peel just the top off the shrink, and confirm the voltage readings by probing directly on the solder. It could just be jst plug wierdness.

In fact, it's quite possible the whole thing was caused by a poor contact at the chargers jst plug. More typical though, is a 0v reading on a cell for that. Not a 5v reading.