Chemistry: electrical current producing apparatus – product – and – Current producing cell – elements – subcombinations and... – Cell enclosure structure – e.g. – housing – casing – container,...
Reexamination Certificate
1999-05-28
2001-07-17
Brouillette, Gabrielle (Department: 1745)
Chemistry: electrical current producing apparatus, product, and
Current producing cell, elements, subcombinations and...
Cell enclosure structure, e.g., housing, casing, container,...
C429S224000, C429S229000
Reexamination Certificate
active
06261717
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention relates to batteries.
Batteries, such as alkaline batteries, are commonly used as energy sources. Generally, alkaline batteries include a cathode, an anode, a separator, and an electrolytic solution. The cathode is typically formed of an active material (e.g., manganese dioxide), carbon particles, and a binder. The anode can be a gel including an active material (e.g., zinc particles). The separator is usually disposed between the cathode and the anode. The electrolytic solution, which is dispersed throughout the battery, can be a hydroxide solution.
Alkaline batteries include the conventional AA, AAA, AAAA, C, and D batteries commonly sold in stores. These conventional alkaline batteries include a cylindrical container containing a central, cylindrical zinc gel anode surrounded by a ring-shaped manganese dioxide cathode.
It generally is desirable for a battery to have a long life. One measure of the life of a battery is the length of time the battery can discharge under a given load before the voltage drops to an unacceptable level.
Mick et al., U.S. Pat. No. 5,869,205 (“the Mick patent”) describes a battery which has an enhanced “service performance” (i.e., a longer life). According to Mick, the service performance in conventional alkaline batteries is limited by the restricted “anode-to-cathode interface area” in the alkaline batteries. The Mick patent gets around this restriction by replacing the center cylindrical cavity that, for example, is the zinc anode in conventional alkaline batteries with a plurality of cylindrical cavities that together make up the anode. By replacing, for example, a central zinc anode with a zinc anode including multiple cavities, the interface area between the zinc anode and the cathode is increased, providing the enhanced service performance.
SUMMARY OF THE INVENTION
The life, or service performance, of a battery also depends on the efficiency with which the battery uses the active materials of the anode and the cathode during discharge. This invention relates to a battery including multiple cavities which efficiently use the active materials in the anode and cathode.
More particularly, in one aspect the invention features a battery including a housing, a first electrode within the housing, a second electrode within the housing, and a separator between the first and second electrodes. The second electrode includes a plurality of cavities within the first electrode. The battery has a length and, at some position along the length of the battery, each of the cavities is a minimum distance (d
1
) from the housing and a minimum distance (d
2
) from each of the other cavities, with each ratio d
2
:d
1
for each cavity being between 1.5:1 and 2.5:1, preferably between 1.7:1 and 2.3:1, more preferably between 1.8:1 and 2.2:1, and most preferably between 1.9:1 and 2.1:1. Each ratio d
2
:d
1
can be the average ratio d
2
:d
1
along the length of the battery. The ratio can be determined, for example, at the mid-point along the length of the battery, or a third of the distance along the length of the battery, or two-thirds of the distance along the length of the battery. Preferably, at least 50 percent of, more preferably at least 75 percent of, and most preferably substantially the entire outer circumference of each cavity at that position fulfills this relationship. The housing preferably is cylindrical.
The minimum distance (d
1
) between a cavity and the housing can be measured by determining the minimum distance between a surface of the first electrode adjacent the cavity and a surface of the first electrode adjacent the housing. The minimum distance (d
2
) between two cavities is measured at the same position along the length of the battery by determining the minimum distance between a surface of the first electrode adjacent one cavity and a surface of the first electrode adjacent the second cavity.
Preferably, the ratio d
2
:d
1
, for each cavity is an average of between 1.5:1 and 2.5:1, more preferably between 1.7:1 and 2.3:1, and most preferably between 1.8:1 and 2.2:1 or even between 1.9:1 and 2.1:1.
In another aspect, the invention also features a battery including a housing, a first electrode within the housing, and a separator between the first and second electrodes. But this aspect of the invention, the second electrode includes two generally D-shaped cavities within the first electrode. Preferably, the flat side of the D-shaped cavities face each other, and the cavities have the ratio d
2
:d
1
discussed above.
In a third aspect, the invention again features a battery having a housing, a first electrode within the housing, and a separator between the first electrode and the second electrode. But this aspect of the invention, the second electrode includes three or more generally triangular-shaped cavities within the first electrode. Preferably, the housing is cylindrical and a corner of each cavity is directed towards the center of the battery, and when this is the case the side of the triangle generally aligned with the cylindrical housing is curved to match the curvature of the housing. Preferably, the cavities have the ratio d
2
:d
1
, discussed above.
In preferred embodiments, the first electrode is a cathode including manganese dioxide and the second electrode is an anode including zinc. The battery may be, for example, an AA, AAA, AAAA, C, or D battery.
The invention also relates to a battery in which the ratio d
2
:d
1
, described above is present at least once for at least one of the cavities.
Generally, the invention also relates to the current collector/seal arrangement that can be used with the multi-cavity batteries described above. The battery includes a top cap on an end of the battery, a seal between the top cap and the anode and cathode, and a multi-prong current collector. As end of each prong is electrically connected with the top cap, and each prong passes through the seal and into one of the anode cavities.
Other features and advantages of the invention will be apparent from the description of the preferred embodiments thereof, and from the claims.
REFERENCES:
patent: 2185756 (1940-01-01), Spicer
patent: 2980747 (1961-04-01), Daly
patent: 4281046 (1981-07-01), Davis, Jr.
patent: 4283470 (1981-08-01), Freeman et al.
patent: 4318968 (1982-03-01), Berger et al.
patent: 4360575 (1982-11-01), Brennan
patent: 5045415 (1991-09-01), Witehira
patent: 5248572 (1993-09-01), Shoji et al.
patent: 5294499 (1994-03-01), Furukawa et al.
patent: 5434019 (1995-07-01), Zhang et al.
patent: 5464709 (1995-11-01), Getz et al.
patent: 5472806 (1995-12-01), Meintjes
patent: 5482796 (1996-01-01), Wang et al.
patent: 5545492 (1996-08-01), Zito
patent: 5576116 (1996-11-01), Sanchez et al.
patent: 5639578 (1997-06-01), Urry
patent: 5674639 (1997-10-01), Urry
patent: 5677080 (1997-10-01), Chen
patent: 5682288 (1997-10-01), Wani
patent: 5821012 (1998-10-01), McCullough
patent: 5869205 (1999-02-01), Mick et al.
patent: 5948561 (1999-09-01), Urry
patent: 2 622 359 A1 (1989-04-01), None
patent: 1036156 (1966-07-01), None
patent: 2-295063 (1990-12-01), None
patent: 7-326347 (1995-12-01), None
patent: 7-326370 (1995-12-01), None
patent: WO 00/01022 (2000-06-01), None
Linden, D., Handbook of Batteries, Second Edition, Mc-Graw-Hill, Inc., NY, p. 8.6., 1995, No Month.
Luo Weifang
Patel Bhupendra K.
Shelekhin Alexander B.
Viveiros Gary T.
Vu Viet H.
Brouillette Gabrielle
Fish & Richardson P.C.
The Gillette Company
Tsang Susy
LandOfFree
Battery having an electrode within another electrode does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Battery having an electrode within another electrode, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Battery having an electrode within another electrode will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2558388