The non-@F02321@ associated with the charging of the @I03084@ at an electrode-solution @I03082@, given by: \[i_{\mathrm{DL}}=\frac{\mathrm{d}(\sigma \ A)}{\mathrm{d}t}\] where \(\sigma \) = @S06159@ of the double layer, \(A\) = area of the electrode-solution @I03082@ and \(t\) = time. Capital letters should be used as subscripts to avoid the possibility of confusing this symbol with that for the @L03534@.