NOVELTY - The method involves providing the cell container containing two one-piece or multi-piece electrodes and separator which is filled with flowable electrolyte. The amount of electrolyte to be filled in is determined before the electrolyte is filled in, while taking into account the actual thickness and the actual weights of the electrodes located in the cell container and the separator located in the cell container.    USE - Method for producing electrochemical cell such as secondary battery, double-layer capacitor, electrolytic capacitor or fuel cell (all claimed).    ADVANTAGE - The individual case quantity filled electrolyte is optimized based on model-based estimate of the free volume. The relationship between the thickness and weights of the components and the resulting free volume can be easily determined experimentally for the cells to be produced using statistical methods. The filling amount of electrolyte is calculated according to the model of input variables and the optimum electrolyte capacity. The to-be-filled amount of electrolyte is determined with both the volume and weight, in order to compensate measurement errors. The mathematical formula is determined for calculating the electrolyte quantity which is determined by parameters that influence the void volume within the cell in reality. The two-dimensional relationship allows fairly reliable determination of the amount of electrolyte be filled in a relatively simple way. The large series production can be achieved, since the variation in the free volume within production batch is not so great. The requirements on the dynamics of electrolyte capacity determination can reduced, which increases the process reliability and reduces the investment costs.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) electrochemical cell; and    (2) plant for producing electrochemical cell.    DESCRIPTION OF DRAWING(S) - The drawing shows a graphical view illustrating the size distribution of the actual free volume in product lot. (Drawing includes non-English language text)