Balancer in supercapacitor

hi all of world
What is the use of balancer in super capacitor?
What to do balancer in supercapacitor?
please help me about balancer?
Thanks.

Balancing is required when 2 or more capacitors are connected in series to prevent one or more capacitor from an overvoltage condition. Ideal capacitors of equal value connected in series will have equal voltages applied to each capacitor. A major reason for mismatch of voltages is mismatch in leakage current. The capacitor with the lowest leakage current (Highest equivalent parallel resistance) will have more voltage applied. To avoid this problem you can connect resistors in parallel with each capacitor such that the resistor current is much larger than the leakage current. There are also active balancers that waste less power than the resistor method. Another reason for voltage mismatch is mismatch in capacitance. For two capacitors C1, C2 connected in series, and applied voltage V, the voltage across C1 will be V(C2/(C1 + C2)). If C1 and C2 are equal, then the voltages will be equal.

hi kral
Thank you for your help
please more explanation about this subject "There are also active balancers that waste less power than the resistor method".

ali.masho,
The idea behind active balancing is to equalize the voltage across capacitors connected in series without drawing excessive current. This site provides some information, along with links to other sites.

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Kral said:

ali.masho,
The idea behind active balancing is to equalize the voltage across capacitors connected in series without drawing excessive current. This site provides some information, along with links to other sites.

Click to expand...

Here is the link that I forgot to include in my previous post:
http://www.instructables.com/id/Lets-learn-about-Super-Capacitors-A-Practical-G/step7/Balancing-Your-Series-Banks/
Sorry about the omission.

From what I have experenced you need a sharing resistor across each cap to make the lower ESR resistors charge and hence share.