Chemistry: electrical current producing apparatus – product – and – Preserving cell in storage feature
Reexamination Certificate
1999-06-25
2001-05-01
Bell, Bruce F. (Department: 1741)
Chemistry: electrical current producing apparatus, product, and
Preserving cell in storage feature
C429S057000, C429S059000, C429S060000, C429S163000, C429S231900, C429S231950, C029S623100
Reexamination Certificate
active
06224995
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates in general to electrochemical cells/batteries, and more particularly, to an electrochemical cell that comprises stackable lithium ion batteries which may have any three dimensional freeform geometric configuration and which require only a lightweight casing.
2. Background Art
Lithium ion rechargeable batteries for use in all types of applications are well known in the art. Generally, lithium batteries are desirable over other types of rechargeable batteries, including nickel cadmium and nickel metal hydride batteries, due to their lighter weight, energy density and overall efficiency, among other advantages.
Generally, it is desirable to have as light of a battery as possible. Indeed current lithium ion batteries have been produced which have the capacity and the cyclability for use in all types of consumer devices, including, but not limited to portable telephones and lap top computers. However, the current batteries utilize relatively heavy and cumbersome casings.
In particular, battery casings generally comprise a rigid and heavy material in a generally cylindrical or prismatic shape. The rigid material prevents buckling of the casing which is caused by internal pressures. The internal pressures are derived from the generation of gas through the decomposition of the electrolyte or of various constituents within the battery. In addition, the casings are typically nickel plated steel which reduces the likelihood of corrosion.
Further, especially in prismatically shaped cells, the individual cells that comprise a battery are generally strongly biased against each other through the use of spring plates. The use of strong spring plates increases the weight of the battery. In addition, the spring plates occupy space which could otherwise be used for additional cells which could then increase the capacity of the battery.
Lastly, these batteries, due to the necessary housings and spring plates to apply uniform pressure onto the cells, are generally available in common, simple configurations, such as cylinders, prisms, cubes and other box-like shapes and configurations. As such, where the battery container is of a shape that is not such a common shape, the prior art utilizes conventionally shaped batteries within the non-uniform battery container. As a result, a portion of the space within the battery container remains empty, and, in turn, comprises dead space.
SUMMARY OF THE INVENTION
The battery apparatus of the present invention comprises a casing, at least two stacked lithium ion cells, means for maximizing the utilization of the casing and means for substantially precluding inadvertent deformation of the casing. Each of the at least two stacked lithium ion cells are electrically associated with each other and positioned within the casing. The utilization maximizing means maximizes the utilization of the inner periphery of the casing by the cells. The deformation preclusion means is operatively associated with the lithium ion cells. The deformation preclusion means substantially precludes inadvertent deformation of the at least two lithium ion cells during cell cycling and storage.
In a preferred embodiment, the deformation preclusion means comprises means for substantially precluding gas generation within the cell. The gas generation preclusion means substantially precludes gas generation within the cell during decomposition of chemical constituents within the cells, during cell cycling and storage.
Preferably, the utilization maximizing means comprises the shaping of each of the cells independently, to the shape of the inner periphery of the casing. In one such embodiment, each of the at least two lithium ion cells comprises a freeform geometric configuration. In such an embodiment, the shape of any one of the cells is independent relative to any of the other cells.
In a preferred embodiment, the at least two stacked lithium ion cells comprise at least two groups of at least two stacked lithium ion cells. In such an embodiment, at least one group of at least two stacked lithium ion cells comprises a freeform shape that is different than the other of the at least two groups of at least two stacked lithium ion cells.
In another preferred embodiment, at least one of the at least two groups of stacked lithium ion cells comprises at least two stacked lithium ion cells which are formed in a monolithic construction. Inasmuch as the contemplated lithium ion cells are substantially precluded from the generation of the cells may be of a monolithic construction, or may otherwise be maintained in a stacked orientation, without requiring the aid of windings, springs, clamps or other rigid retaining structures.
The invention further includes a process for fabricating a battery apparatus. The process includes the step of forming a casing having a non-uniform periphery for housing the at least two stackable lithium ion cells. Next, the process includes the step of fabricating the at least two lithium ion cells. This step comprises the step of shaping each of the cells so as to maximize the utilization of the inner periphery of the casing and the step of associating a chemical compound within the cells. The chemical compound substantially precludes inadvertent deformation of the casing by the cells during cell cycling and storage, once the cells are positioned in the casing. Lastly, the process includes the step of positioning the at least two stackable lithium ion cells within the casing.
In another preferred embodiment, the step of shaping the cells comprises the step of shaping the cells in a free-form geometric configuration.
In yet another preferred embodiment, wherein each cell includes a first electrode having a carbonaceous surface, a second electrode and an electrolyte which includes a solvent, the step of associating a chemical compound comprises the step of associating the chemical compound with the carbonaceous surface of the first electrode. This forms a passivating layer which substantially precludes association of the solvent of the electrolyte with the carbonaceous surface. In addition, the step of associating a chemical compound further comprises the step of decomposing the electrolyte to form a passivating layer during cell cycling and storage without generating any significant amounts of gas during such decomposition.
REFERENCES:
patent: 1981533 (1934-11-01), Williams
patent: 4064329 (1977-12-01), Naylor
patent: 4186246 (1980-01-01), Sugalski
patent: 4278744 (1981-07-01), Athearn
patent: 4374186 (1983-02-01), McCartney et al.
patent: 4409304 (1983-10-01), Gerard et al.
patent: 4582767 (1986-04-01), Morioka et al.
patent: 4889777 (1989-12-01), Akuto
patent: 5134046 (1992-07-01), Chow et al.
patent: 5326653 (1994-07-01), Chang
patent: 5374490 (1994-12-01), Aldecoa
patent: 5401595 (1995-03-01), Kagawa et al.
patent: 5432017 (1995-07-01), Hassemer et al.
patent: 5445906 (1995-08-01), Hobson et al.
patent: 5503948 (1996-04-01), MacKay et al.
patent: 5621618 (1997-04-01), Komiyama
patent: 5704803 (1998-01-01), Oshima et al.
patent: 5744261 (1998-04-01), Muffoletto et al.
patent: 6040078 (2000-03-01), Fauteux et al.
Farina Michael
Fauteux Denis G.
Rounds, III Robert
Bell Bruce F.
Factor & Partners
Mitsubishi Chemical Corporation
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