Abstract: A metal-air battery pack is disclosed for external assembly to a portable electronic device with a battery compartment. The battery pack electrically connects to the electronic device through an existing connector of the device that is located in the battery compartment of the device.

Abstract: An improved cathode is described which comprises an air-permeable, top coat deposited on the face of the cathode current collector screen. The top coat contains a CO.sub.2 absorber such as magnesium hydroxide which absorbs CO.sub.2 from the air and prevents CO.sub.2 from reacting with or neutralizing the electrolyte. The layer is composed of a dispersion of metal hydroxide in a hydrophobic binder such as polytetrafluoroethylene. The top coat is preferably formed of a first, outer gas flow limiting layer of hydrophobic material absent any CO.sub.2 absorber and a second, inner layer adjacent the current collector of hydrophobic binder containing a CO.sub.2 absorber.

Abstract: An air manager system for a metal-air battery cell having an air cathode, the air manager system producing a flow of air through the air manager system and battery cell and directing a first air flow adjacent to the air cathode to provide reactant air and directing a second air flow adjacent to a portion of the battery cell isolated from the air cathode to provide cooling of the battery cell, preferably near the anode. The air manager system may be used with multiple cell metal-air battery packs. Heat exchange between the isolated air flows may be facilitated, and the reactant air may be recirculated for uniform cooling.

Abstract: A zinc anode plate is completely wrapped in a cloth anode separator containing liquid electrolyte. A hydro-gel material packed in an inert mesh separator is sandwiched between the wrapped anode and an air cathode which is in the form of a carbon membrane. The gel material is sufficiently permeable to oxygen to allow oxygen flow therethrough during charging and discharging cycles of the battery, and provides chemical reactive communication between the air cathode and the electrolyte in the anode separator without allowing electrolyte to pass therethrough. The permeability of the gel material is selected such that during charging of the battery, oxygen generated by the anode exerts sufficient pressure at the interface of the anode separator and gel material to cause electrolyte to be recirculated through the edges of the cloth anode separator to the opposite layer thereof, thereby preventing depletion of electrolyte to the anode.

Abstract: A consumable anode of a reactive metal such as lithium is provided as a layer on a flexible, conductive substrate. The anode is preferably in the form of an elongated tape wound on a reel. The anode tape is fed from the reel into and through an elongated electrolyte reaction chamber formed between the surface of the anode tape and an opposed cathode. The ends of the compartment contain seals for retaining electrolyte between the electrodes. The tape is rewound on a driven take up reel.

Abstract: A metal-air battery power supply for powering a device includes an enclosed container having an air inlet, an air outlet, and an array of connected metal-air battery cells therein. The container is sealed during non-use. When a power switch is turned on, the air inlet and air outlet are opened. At the same time, the residual low power of the battery cells is used to start a fan positioned near the air inlet. The fan initiates an air flow across the battery cells to further increase the power supply output. The power supply output is limited to the use requirement of the device by varying the fan speed in response to instructions from the device. Precise control of the battery cells' exposure to air extends the lifetimes of the cells.

Abstract: A metal-air battery has a base for containing the active battery materials and a lid located on top of and fitted with the base. The flexible bottom surface of the base is curved to permit an expansion of the battery container during battery discharge. The air cathode is retained by a ledge in the base as well as by channels in the lid to prevent separation between the electrolyte and the air cathode membrane during battery discharge. An air chamber housing having inlet and outlet air ducts is located above the air cathode membrane for continuous air flow and optimal battery operation. The air ducts are sealed during storage to extend the shelf life of the battery.

Abstract: The intrinsic nonuniformity of a radioisotope camera having an array of photomultiplier tubes viewing a scintillator crystal assembly is improved by comparing an internally generated correction factor from 1 to n, assigned to a location where a radiation event has been detected, to a random number between 1 and n and then discarding the radiation event datum if the correction factor is less than the random number. Correction factors are first generated by comparing the count at each location with an average minimum count in the presence of a uniform flood source.