Abstract: A proton conducting membrane (16) for a fuel cell comprises light-transmissive proton conducting material (102, 104) and light scattering material (106) for scattering light within the membrane, the membrane further comprising a light guide (108) through which light can enter the membrane. Also disclosed is a fuel cell comprising the membrane.

Abstract: A battery comprises electrodes formed from the same metal oxide and an electrolyte solution comprising a source of cations which can be intercalated into the metal oxide. The battery can store electrical charge by connecting one of the electrodes to an external power source to reduce at least some of the metal atoms in the metal oxide forming the electrode from a higher to a lower oxidation state through the uptake of intercalating cations from the electrolyte and thereby create a potential difference between the electrodes, which electrical charge can be discharged by electrically connecting the electrodes. The electrodes are preferably formed from a multi-valent transition metal oxide, such as a tungsten, vanadium, cobalt or molybdenum oxide, more preferably tungsten trioxide. The intercalating cations are preferably protons and the electrolyte an acid.

Abstract: A battery comprises electrodes formed from the same metal oxide and an electrolyte solution comprising a source of cations which can be intercalated into the metal oxide. The battery can store electrical charge by connecting one of the electrodes to an external power source to reduce at least some of the metal atoms in the metal oxide forming the electrode from a higher to a lower oxidation state through the uptake of intercalating cations from the electrolyte and thereby create a potential difference between the electrodes, which electrical charge can be discharged by electrically connecting the electrodes. The electrodes are preferably formed from a multi-valent transition metal oxide, such as a tungsten, vanadium, cobalt or molybdenum oxide, more preferably tungsten trioxide. The intercalating cations are preferably protons and the electrolyte an acid.

Abstract: A proton conducting membrane (16) for a fuel cell comprises light-transmissive proton conducting material (102, 104) and light scattering material (106) for scattering light within the membrane, the membrane further comprising a light guide (108) through which light can enter the membrane. Also disclosed is a fuel cell comprising the membrane.