Bipolar lead acid battery cells with increased energy density

A bipolar lead acid battery comprising:

• a stack of at least two cells electrically arranged in series with a positive face of each cell contacting a negative face of an adjacent cell, wherein each of the cells comprises:
• a negative electrode including a negative electrode plate and negative active material;
• a positive electrode including a positive electrode plate and positive active material, the positive plate comprising a metal foil with an electrically conductive film thereon;
• a separator between the electrodes, wherein the separator includes an electrolyte;
• and
• a cell enclosure surrounding the negative and positive electrodes and the separator that seals the cell so as to contain the electrolyte within the cell, the cell enclosure comprising a plurality of perforations therein that provide for electrical connectivity between adjacent cells.