NOVELTY - An electrochemical cell (200), comprises an anode (210), a cathode (220) containing a gas diffusion electrode and having first and second surfaces, an inlet for gaseous oxidant that is in contact with the first surface of the cathode, a channel (240) that is contiguous with the anode and with the second surface of the cathode, and a liquid electrolyte in the channel, where water generated at the cathode is transported by osmosis into the liquid electrolyte. The cathode comprises a blocking layer at the second surface.    USE - As electrochemical cell e.g. fuel cell such as methanol fuel cell for generating electricity (claimed), electrolyte membrane fuel cells, alkaline fuel cells, phosphoric acid fuel cells, molten carbonate fuel cells, and solid oxide fuel cells useful in e.g. portable and mobile fuel cell systems and other electronic devices, such as in cellular phones, laptop computers, DVD players, televisions, personal data assistants (PDAs), calculators, pagers, hand-held video games, remote controls, cassette players, compact disc (CD) players, radios, audio recorders, video recorders, cameras, navigation systems, and wristwatches.    ADVANTAGE - The liquid electrolyte having sufficient osmotic pressure into an electrochemical cell can allow the in situ removal of liquid water or prevention of liquid water from or within the cathode of the electrochemical cell. The blocking layer between the liquid electrolyte and the cathode provides a reduction in the crossover of fuel to the cathode. The electrochemical cells incorporating the liquid electrolyte can operate under neutral water conditions without using parasitic external water management devices such as condensers or evaporators. Coating or layer present on the side of the gas diffusion electrode (GDE) facing the electrolyte preferably allows the conduction or permeation of ions to the catalyst layer and for back-permeation of water to the electrolyte, without allowing significant liquid breakthrough or hydraulic flooding of liquid electrolyte into the gas flow stream channels. The electrochemical cell produces a current density of 200 mA/cm2 without cathode flooding, in the absence of external water management component. The electrochemical cell minimizes the risk of fuel crossover to the cathode by using a barrier layer between the cathode and liquid electrolyte and/or by using two liquid streams within the liquid electrolyte.    DETAILED DESCRIPTION - An electrochemical cell (200), comprises an anode (210), a cathode (220) containing a gas diffusion electrode and having first and second surfaces, an inlet for gaseous oxidant that is in contact with the first surface of the cathode, a channel (240) that is contiguous with the anode and with the second surface of the cathode, and a liquid electrolyte in the channel, where water generated at the cathode is transported by osmosis into the liquid electrolyte. The liquid electrolyte has an osmotic pressure of at least 1.2 (preferably at least 10) MPa. The liquid electrolyte is transported in the channel at a rate of at least 0.1 ml/sec. The cathode comprises a blocking layer at the second surface. The blocking layer comprises a catalyst, and a polymer electrolyte membrane. The cell further comprises a porous separator between the first and second streams. The second stream further comprises a fuel. The fuel comprises a liquid electrolyte. An INDEPENDENT CLAIM is included for generating electricity from the electrochemical cell involving flowing gaseous oxidant through the inlet in contact with the first surface of the cathode, flowing the liquid electrolyte through the channel, and contacting the anode with a fuel, where complementary half-cell reactions take place at the cathode and anode.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic representation of fuel cell.    electrochemical cell (200)    anode (210)    cathode (220)    liquid electrolyte (230)    channel (240)    electrolyte inlet (242)    fuel channel (250)    fuel inlet (252)    oxidant channel (260)    oxidant inlet (262)    blocking layer. (270)