Batteries are not balancing, bad charger?

[Erbing]

I have the Thunder AC6 charger, it use to balance my batteries no problem,now none of my 3 gens ace are balancing. Idont think its the battery as 1 is new and wont balance anymore, ex. 4.20 4.19 4.20..
Could my charger be going bad?

[Fink]

Originally Posted by Erbing

I have the Thunder AC6 charger, it use to balance my batteries no problem,now none of my 3 gens ace are balancing. Idont think its the battery as 1 is new and wont balance anymore, ex. 4.20 4.19 4.20..
Could my charger be going bad?

Odd that the charger would just go bad like that.

What happens when you try to balance?

Fink

[JohnRobHolmes]

Being .01v off isn't bad at all, don't even worry about that. The cells are starting to drift in resistance, as they get older it is normal.

[Fink]

Originally Posted by JohnRobHolmes

Being .01v off isn't bad at all, don't even worry about that. The cells are starting to drift in resistance, as they get older it is normal.

That's what I get for not reading the whole post.

Sir Holmes is right - .01v is nothing to worry about. Your charger and batteries are just fine.

Fink

[Draggermirage]

Adding to what they're saying.

If the cells are dangerously unbalanced for any reason, most (if not all) chargers will throw a warning message and attempt to balance (discharge or charge) the individual cells before being put into a charge mode.

Marcus

[Erbing]

Originally Posted by JohnRobHolmes

Being .01v off isn't bad at all, don't even worry about that. The cells are starting to drift in resistance, as they get older it is normal.

Thats good to know, Thanks

The charger shows no error or warning, it will just try to balance charge until the timer turns it off.

Thanks all for the help.

[JohnRobHolmes]

After 4.18v there isn't much capacity to shove in there anyway. Once the charger gets close to peak voltage it reduces the amperage to .1 or .2a, and since it probably can't balance faster than .1a the last little bit of balancing may not occur on older cells. I start to get concerned when my problem cells won't pull above 4.15v during balancing, assuming the charger is accurate enough. That is about 10% less capacity than 4.2v, so the runt cells start to get hurt if the pack is run down all the way.

Typically I set my voltage cutoff between 3.3 and 3.5v per cell depending on how hard I beat on the packs. If it is a 5000mah pack in a scaler, 3.5v is a great point to stop the discharge so there is at least 10% capacity left and no chance of hurting a runt cell. In a higher performance rig with a teeny pack, a lower voltage is better to avoid false cutoff under load. I know some guys turn off the voltage cutoff completely to avoid a shutdown during competition. Ruin a pack or finish the course- typically finishing the course is more important than the pack.