摘要:
In primary cells, the addition of gaseous carbon dioxide to the nonaqueous electrolyte has beneficial effects in terms of minimizing or eliminating voltage delay and reducing Rdc build-up when the cell is subjected to pulse current discharge conditions. For secondary systems, carbon dioxide provided in the electrolyte benefits cycling efficiency. The problem is that carbon dioxide readily degases from an electrolyte prepared under an ambient atmosphere. To prevent this, the carbon dioxide-containing electrolyte is prepared and stored in a carbon dioxide atmosphere. Also, the thusly prepared electrolyte is filed into the casing in a carbon dioxide-containing atmosphere. This prevents degassing of the additive from the electrolyte.
摘要:
A rechargeable alkali metal electrochemical cell, and preferably a lithium-ion secondary cell, constructed of low magnetic susceptibility materials, is described. The non-magnetic characteristics enable the secondary cell to be used within the confines of a Magnetic Resonance Imaging system. The cell includes an electrolyte solution comprising ethylene carbonate, dimethyl carbonate, ethylmethyl carbonate and diethyl carbonate.
摘要:
A method of making electrodes with distributed material loadings used in rechargeable electrochemical cells and batteries is described. This method controls electrode material loading (mass per unit area) along the electrode's length while maintaining uniform compaction throughout the electrode. Such prepared electrode maintain sufficient mechanical flexibility for winding and are compact and robust to have high energy density and long cycle life in rechargeable cells and batteries.
摘要:
An electrochemical cell comprising a lithium anode, a cathode comprising a blank cut from a free-standing sheet of a silver vanadium oxide mixture contacted to a current collector. The active material has having a relatively lower surface area and an electrolyte activating the anode and the cathode is described. By optimizing the cathode active material surface area in a SVO-containing cell, the magnitude of the passivating film growth at the solid-electrolyte interphase (SEI) and its relative impermeability to lithium ion diffusion is reduced. Therefore, by using a cathode of an active material, in a range of from about 0.2 m2/gram to about 2.6 m2/gram, and preferably from about 1.6 m2/gram to about 2.4 m2/gram, it is possible to eliminate or significantly reduce undesirable irreversible Rdc growth and voltage delay in the cell and to extend its useful life in an implantable medical device.
摘要:
A hermetically sealed coin cell is described. The coin cell has the opposite polarity terminals isolated from one another by a glass-to-metal seal. Glassing a conductive disc inside a ring of greater diameter and height forms this seal. The height of the ring is equivalent to the desired height of the cell. The disc acts as one cell terminal, which can be positive or negative, and the ring serves as the other terminal. In plan view, both terminals are on the same side of the cell. This allows for easy mounting and connection to an electric circuit board, and the like.
摘要:
It is known that reforming implantable defibrillator capacitors at least partially restores and preserves their charging efficiency. An industry-recognized standard is to reform implantable capacitors by pulse discharging the connected electrochemical cell about once every three months throughout the useful life of the medical device. A Li/SVO cell typically powers such devices. The present invention relates to methodologies for significantly minimizing, if not entirely eliminating, the occurrence of voltage delay and irreversible Rdc growth in the about 25% to 70% DOD region by subjecting Li/SVO cells to novel discharge regimes. At the same time, the connected capacitors in the cardiac defibrillator are reformed to maintain them at their rated breakdown voltages.
摘要翻译:众所周知,重组可植入除颤器电容器至少部分恢复并保持其充电效率。 行业公认的标准是通过在医疗设备的整个使用寿命期间每三个月大约一次脉冲地排放连接的电化学电池来重建可植入电容器。 Li / SVO单元通常为这些设备供电。 本发明涉及通过使Li / SVO细胞经受新颖的放电方式,在大约25%至70%的DOD区域中显着地最小化(如果不是完全消除)电压延迟和不可逆Rdc生长的方法。 同时,将心脏除颤器中连接的电容器进行重整,以将其维持在额定击穿电压。
摘要:
A new cathode design has a first cathode active material of a relatively low energy density but of a relatively high rate capability contacted to a first cathode current collector and a second cathode active material having a relatively high energy density but of a relatively low rate capability in contact with a second cathode current collector, is described. The first and second cathode current collectors are connected to a common terminal lead. The present cathode design is useful for powering an implantable medical device requiring a high rate discharge application.
摘要:
A lithium ion electrochemical cell having high charge/discharge capacity, long cycle life and exhibiting a reduced first cycle irreversible capacity, is described. The stated benefits are realized by the addition of at least one phosphate additive having the formula: (R1O)P(═O) (OR2) (OR3) and wherein R1, R2 and R3 are the same or different, wherein at least one, but not all three, of the R groups is hydrogen, or at least one of the R groups has at least 3 carbon atoms and contains an sp or sp2 hybridized carbon atom bonded to an sp3 hybridized carbon atom bonded to the oxygen atom bonded to the phosphorous atom.
摘要:
The present invention is directed to at least partially replacing PC and/or DME with a linear carbonate, preferably dimethyl carbonate, and a linear mono-ether, the most preferred being diisopropyl ether, in electrolytes useful for activating alkali metal-containing cells. This electrolyte has improved conductivity and provides electrochemical cells with enhanced discharge performance. A most preferred electrolyte comprises 1,2-dimethoxyethane, propylene carbonate, dimethyl carbonate and diisopropyl ether.
摘要:
An alkali metal secondary electrochemical cell, and preferably a lithium ion cell, activated with an equilibrated quaternary solvent system, is described. The solvent system comprises a mixture of dialkyl carbonates and cyclic carbonates, and preferably a quaternary mixture of dimethyl carbonate, diethyl carbonate, ethylmethyl carbonate and ethylene carbonate with dimethyl carbonate, diethyl carbonate and ethylmethyl carbonate in an equilibrated molar mixture. Lithium ion cells activated with this electrolyte have good room temperature cycling characteristics and excellent low temperature discharge behavior.