摘要:
A lithium electrochemical cell of either a primary or a secondary chemistry activated with an electrolyte having a cyclic carbonate of a ring size equal to or larger than a six-member ring is described. The cyclic carbonate helps to make the anode passivation film ionically conductive to thereby eliminate voltage delay during pulse discharge and to reduce Rdc. Such a cell is particularly well suited for powering an implantable medical device, such as a cardiac defibrillator.
摘要:
An alkali metal/ solid cathode electrochemical cell, such as of a Li/SVO couple, having the cathode material supported on a titanium current collector screen coated with a carbonaceous material is described. The thusly-coated titanium current collector provides the cell with higher rate capability in comparison to cells of a similar chemistry having the cathode active material contacted to an uncoated titanium current collector.
摘要:
An alkali metal/ solid cathode electrochemical cell, such as of a Li/SVO couple, having the cathode material supported on a titanium current collector screen coated with a carbonaceous material is described. The thusly-coated titanium current collector provides the cell with higher rate capability in comparison to cells of a similar chemistry having the cathode active material contacted to an uncoated titanium current collector.
摘要:
A method for providing a physician with an elective replacement indicator (ERI) for an implantable medical device is described. The medical device is powered by an electrochemical having a lithium anode coupled to a sandwich cathode comprising the configuration: SVO/current collector/CF x , with the SVO facing the anode. The indicator is predicated on when the cell's discharge capacity is nearing end-of-life (EOL) based on the theoretical capacity and the discharge efficiency of the SVO and CF x active materials. This serves as an indicator when it is time to replace the medical device.
摘要:
An improved cathode material for nonaqueous electrolyte lithium electrochemical cell is described. The preferred active material is silver vanadium oxide (SVO) coated with a protective layer of an inert metal oxide (M x O y ) or lithiated metal oxide (Li x M y O z ). The SVO core provides high capacity and rate capability while the protective coating reduces reactivity of the active particles with electrolyte to improve the long-term stability of the cathode.
摘要:
A re-balanced lithium ion secondary cell, particularly one comprising LiCoO 2 cathode active material, is described. The preferred anode material is carbonaceous, and the couple is balanced to a ratio of the cathode active material to the anode material of from about 1.35 to about 2.25. This significantly improves the energy density of the secondary cell over that known by the prior art by increasing the charge voltage to at least 4.4V.
摘要:
A new sandwich positive electrode design for a secondary cell is provided comprising a "sacrificial" alkali metal along with a cathode active material. In the case of silver vanadium oxide, the sacrificial alkali metal is preferably lithium. Upon activating the cells, the lithium metal automatically intercalates into the silver vanadium oxide. That way, the sacrificial lithium is consumed and essentially lithiates the silver vanadium oxide. This means that cathode active materials, such as silver vanadium oxide, which before now were generally only used in primary cells, are now useful in secondary cells. In some use applications, silver vanadium oxide is more desirable than typically used lithiated cathode active materials.