An electrochemical system can include transition metal nanoparticles as a promoter for an electrode. The transition metal nanoparticles can include molybdenum (Mo), chromium (Cr), and/or the oxides thereof, which can lower recharge potentials and enhance the efficiency. These promoters promote especially the generation of oxygen and this for several cycles of usage of the electrochemical system which is, as a result, rechargeable.

Example biosensor devices having wake-up batteries and associated methods are disclosed. One example device includes a biosensor that has a first electrode for insertion into a subcutaneous layer beneath a patient's skin, and a second electrode coupled to the first electrode for insertion into the subcutaneous layer, and a first battery to apply a voltage across the first and second electrodes, the first battery at least partially electrically decoupled from the electrodes. The device also includes a second battery having an anode material coupled to the first electrode for insertion into the subcutaneous layer, and a portion of the second electrode. The second battery is activatable upon immersion in an electrolytic fluid. The device also includes a wake-up circuit to receive a signal from the second battery and, in response, to electrically couple the first battery to the first and second electrodes to activate the biosensor.

Disclosed is a battery with an open bottom, comprising a battery assembly and an electrolyte storage box for accommodating an electrolyte. Said battery assembly comprises at least one battery pack, and said at least one battery pack can move between a first position and a second position relative to said electrolyte storage box; in the first position, said at least one battery pack contacts said electrolyte so as to enable said battery with an open bottom to generate electricity, and in the second position, said at least one battery pack is separated from said electrolyte such that said battery with an open bottom is turned off. The battery pack of the battery with an open bottom in the present invention can move between the first and the second positions relative to the electrolyte storage box so as to rapidly contact and react with the electrolyte.

A self-rescuer device comprises an intake pump that creates a gas stream. The gas stream enters a first sieve that separates carbon dioxide, carbon monoxide, and oxygen from the gas stream to create a mixture. The remaining gas stream flows to a second sieve that separates nitrogen from the remaining gas stream and vents the residual gas to outside of the self-rescuer device through a residual output. The separated mixture is directed to a gas processor separates the oxygen from the mixture. A nitrogen storage canister coupled to the separated output of the second sieve stores the separated nitrogen, and an oxygen storage canister coupled to the separated output of the first sieve stores and concentrates the separated oxygen until a purity threshold is met. Habitable nitrogen and oxygen are metered from their storage canisters and supplied to a user of the device through a breathing mask within an exterior mask shell.

Example biosensor devices having wake-up batteries and associated methods are disclosed. One example device includes a biosensor that has a first electrode for insertion into a subcutaneous layer beneath a patient's skin, and a second electrode coupled to the first electrode for insertion into the subcutaneous layer, and a first battery to apply a voltage across the first and second electrodes, the first battery at least partially electrically decoupled from the electrodes. The device also includes a second battery having an anode material coupled to the first electrode for insertion into the subcutaneous layer, and a portion of the second electrode. The second battery is activatable upon immersion in an electrolytic fluid. The device also includes a wake-up circuit to receive a signal from the second battery and, in response, to electrically couple the first battery to the first and second electrodes to activate the biosensor.