PCT No. PCT/IB95/00936 Sec. 371 Date Jun. 5, 1998 Sec. 102(e) Date Jun. 5, 1998 PCT Filed Oct. 31, 1995 PCT Pub. No. WO97/16838 PCT Pub. Date May 9, 1997A plurality of series-connected elements are arranged, as parallel elongated stripes, on a common electrically insulating transparent substrate (1). Each element comprises a photoanode (4), a porous counterelectrode or cathode (6) and an intermediate electrically insulating porous layer (5) separating the photoanode (4) from the cathode (6). The pores of the intermediate layer (5), the photoanode (4) and the cathode (6) are at least partially filled with an electron transferring electrolyte. An intermediate layer (2) of a transparent electrically conducting material is interposed between the substrate (1) and each photoanode (4). The cathode (6) of the first photovoltaic element of the series is electrically connected with a first terminal (9) of the battery. The cathode (6) of each following element is connected with the intermediate conducting layer (2) of the preceding element, over a gap (3) separating the respective intermediate layers (2) of these two elements.