Chemistry: electrical current producing apparatus – product – and – Having movable mechanical means to provide relative motion... – Means moves electrolyte externally of electrode chamber
Reexamination Certificate
1999-05-04
2001-07-17
Brouillette, Gabrielle (Department: 1745)
Chemistry: electrical current producing apparatus, product, and
Having movable mechanical means to provide relative motion...
Means moves electrolyte externally of electrode chamber
C429S071000, C429S072000
Reexamination Certificate
active
06261714
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates generally to energy storing devices, such as batteries. More particularly, the present invention relates to a spill and leak containment system for zinc-bromine batteries, which are often used in transportable energy storage systems.
BACKGROUND OF THE INVENTION
Large-scale energy storage systems can be created by coupling a number of energy storing devices such as batteries to one another. Such systems are useful for storing power during off-peak times and supplying electric power to an electric power transmission system during times of peak usage. This process is known as “peak shaving.” A system that can be used to accomplish peak shaving is shown in U.S. Pat. No. 5,610,802 (the “'802 Patent”).
Systems such as the one in the '802 Patent are most often implemented with metal-halogen batteries such as zinc bromine batteries. While zinc-bromine batteries have several advantages over other types of batteries, most such batteries suffer from bromine leakage problems. Bromine leakage causes power losses and corrosion and handling problems. Handling problems can be particularly troublesome since bromine is hazardous to both plants and animals.
Often times bromine leaks occur through battery vents which are provided to allow the internal pressure to equalize with the ambient pressure outside the battery, and for the escape of gases that build up inside the battery. However, vents equipped with scrubbers can reduce the effects of such leaks. More troublesome are leaks which occur in the battery components due to improper sealing or joining. These leaks are often compounded when batteries or modules containing batteries are transported, as the motion and vibration associated with such movement tends to further separate imperfect joints and seals in a battery.
In response to these problems, methods of strongly sealing the electrodes and separators used to create the electrochemical cells in zinc-bromine batteries have been developed. However, other components such a pump mounts, plumbing, and reservoirs may be imperfectly sealed, joined, or constructed and leak bromine, whether in a liquid or gaseous form. To date, most attempts to address such leaks have focused on providing sumps and other basins to catch and collect liquid bromine. However, these attempts have not been completely effective. Thus, there is a need for improved designs that reduce and prevent spills and leaks of bromine from zinc-bromine batteries.
SUMMARY OF THE INVENTION
Therefore, an object of the present invention is to provide a bromine containment system for a zinc-bromine battery. Another object is to provide a bromine vapor containment system that reduces bromine emissions from a battery module.
These and other objects and advantages are achieved in a battery module which includes one-piece, electrolyte reservoirs. Constructed in such a fashion, the reservoirs in the present invention exhibit improved structural integrity over prior-art reservoirs that have seams, welds, or other junctures as a result of being manufactured from multiple components. In the preferred embodiment, the reservoirs are blow molded from high density polyethylene in a rotational fashion.
In addition to their one-piece design, the reservoirs in the present invention are designed with pump mountings or openings positioned near their tops. The pump openings are surrounded by sumps. Positioning the pump openings near the top of each reservoir reduces the amount of electrolyte that might spill out of the reservoirs in the event of a leak or breach in the seal between the pumps and pump openings. If there is a leak, the sumps contain the small amount spilled.
Each of the rotational molded reservoirs also includes one or two raised cylindrical openings mounted in a non-sump area that provide access to the interior of the reservoir. The openings are sealed with lids, which may have their own openings or ports for plumbing and other connections. Positioning the openings on the top of the reservoirs, instead of the sides or bottom, helps reduce the amount of liquid which may leak from the reservoirs in the event of a leak from or breach of the lids. In order to further reduce the leakage of vapor and liquid, the lids are fitted with one or two O-rings to provide an air tight seal.
Other features of the invention involve the sensors and ports on the reservoir. A float sensor is positioned within each electrolyte reservoir in order to monitor the electrolyte level. A controller (such as a microprocessor) monitors the levels and in the event of a non-normal level, the system shuts down until the unbalanced condition has been corrected. Ports in the lids for the cylindrical openings are used for filling the system with electrolyte and balancing the pressure of the system. In order to balance pressure in the system, a pressure equalization tube is coupled to the electrolyte reservoirs. Specifically, the tube is connected from the anolyte reservoir to the catholyte reservoir in order to equalize the pressure in the two electrolyte systems. This helps maintain an equal pressure in each of them. Furthermore, a fill tube can be coupled to electrolyte fill containers when each of the electrolyte reservoirs is being initially filled. This tube acts as a vapor transport tube and allows for the exchange of vapors to occur between the electrolyte container and the battery reservoir while electrolyte fluid is being transferred. This prevents electrolyte vapor from escaping into the atmosphere where it might be potentially harmful to personnel setting up the system.
Other features and advantages of the present invention will become apparent by reference to the detailed description below taken in combination with the accompanying drawings.
REFERENCES:
patent: 467372 (1892-01-01), Gendron
patent: 1354800 (1920-10-01), Butler
patent: 2346313 (1944-04-01), Keller
patent: 2584117 (1952-02-01), Elrod, Jr.
patent: 3357860 (1967-12-01), Stachurski
patent: 3900640 (1975-08-01), Vechiotti
patent: 3928078 (1975-12-01), Köthe et al.
patent: 3966870 (1976-06-01), Vecchiotti
patent: 3993507 (1976-11-01), Hardigg
patent: 4304823 (1981-12-01), Lemelson
patent: 4491625 (1985-01-01), Kantner
patent: 4550065 (1985-10-01), Fujii et al.
patent: 4614693 (1986-09-01), Hashimoto et al.
patent: 4614694 (1986-09-01), Manthis
patent: 4663251 (1987-05-01), Sasaki et al.
patent: 5168016 (1992-12-01), Hashimoto et al.
patent: 5498488 (1996-03-01), Stocchiero
patent: 5543243 (1996-08-01), Brecht
patent: 5601943 (1997-02-01), Eidler et al.
patent: 5607788 (1997-03-01), Tomazic
patent: 5610802 (1997-03-01), Eidler et al.
patent: 5813838 (1998-09-01), Bae et al.
patent: 5862830 (1999-01-01), Landau
Eidler Phillip A.
Lex Peter J.
Brouillette Gabrielle
Godfrey & Kahn S.C.
Kees Nicholas A.
Wills M.
ZBB Technologies, Inc.
LandOfFree
Spill and leak containment system for zinc-bromine battery does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Spill and leak containment system for zinc-bromine battery, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Spill and leak containment system for zinc-bromine battery will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2512447