Patent ID: 7283349

Claim:
An electric double layer capacitor comprising: a pair of current collectors; a positive polarizable electrode which is provided on one of the pair of current collectors, constructed so as to include activated carbon of a weight W + , and has a capacitance C + ; a negative polarizable electrode which is provided on the other of the pair of current collectors, constructed so as to include activated carbon of a weight W − , and has a capacitance C − ; a separator interposed between the positive and negative polarizable electrodes; and an organic electrolytic solution which impregnates at least the positive and negative polarizable electrodes and the separator; wherein the capacitance C + of the positive polarizable electrode and the capacitance C − of the negative polarizable electrode satisfy the condition C − /C + =0.6 to 1.0, and the weight W + of the activated carbon included in the positive polarizable electrode and the weight W − of the activated carbon included in the negative polarizable electrode satisfy the condition W − /W + =1.1 to 2.0.