Patent Publication Number: US-2010124688-A1

Title: Regulator Valve for a Fluid Consuming Battery

Description:
BACKGROUND OF THE INVENTION 
     The present invention generally relates to fluid regulating systems for batteries, and more particularly relates to a regulator valve for controlling the entry of fluid, such as air, into electrochemical batteries having fluid consuming electrodes. 
     Electrochemical battery cells that use a fluid, such as oxygen and other gases from outside the cell as an active material to produce electrical energy, such as air-depolarized, air-assisted and fuel cell battery cells, can be used to power a variety of portable electronic devices. For example, air enters into an air-depolarized or air-assisted cell, where it can be used as, or can recharge, the positive electrode active material. The oxygen reduction electrode promotes the reaction of the oxygen with the cell electrolyte and, ultimately, the oxidation of the negative electrode active material with the oxygen. The material in the oxygen reduction electrode that promotes the reaction of oxygen with the electrolyte is often referred to as a catalyst. However, some materials used in oxygen reduction electrodes are not true catalysts because they can be at least partially reduced, particularly during periods of relatively high rate of discharge. 
     One type of air-depolarized cell is a zinc/air cell. This type of cell uses zinc as the negative active material and has an aqueous alkaline (e.g., KOH) electrolyte. Manganese oxides that can be used in zinc/air cells are capable of electrochemical reduction in concert with oxidation of the negative electrode active material, particularly when the rate of diffusion of oxygen into the air electrode is insufficient. These manganese oxides can then be reoxidized by the oxygen during periods of lower rate discharge or rest. 
     Air-assisted cells are hybrid cells that contain consumable positive and negative electrode active materials, as well as an oxygen reduction electrode. The positive electrode can sustain a high discharge rate for a significant period of time, but through the oxygen reduction electrode, oxygen can partially recharge the positive electrode during periods of lower or no discharge, so oxygen can be used for a substantial portion of the total cell discharge capacity. This generally means the amount of positive electrode active material put into the cell can be reduced and the amount of negative electrode active material can be increased to increase the total cell capacity. Examples of air-assisted cells are disclosed in commonly assigned U.S. Pat. Nos. 6,383,674 and 5,079,106. 
     A number of approaches have been proposed to control the amount of air entering the cells. For example, valves have been used to control the amount of air such as those disclosed in U.S. Pat. No. 6,641,947, U.S. Patent Application Publication No. 2003/0186099 and U.S. Patent Application Publication No. 2008/0085443. However, some conventional valves are typically difficult to implement with batteries and require relatively complicated electronics or external means to operate the valves. 
     It is therefore desirable to provide for an air manager that allows for reliable and easy control of fluid entry to a fluid consuming electrode of a fluid consuming battery. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the present invention, a fluid regulator is provided for supplying fluid to a fluid consuming battery. The regulator includes a valve housing adapted to be in fluid communication with a fluid consuming electrode of a fluid consuming battery cell. The valve housing has an opening. The regulator also includes an axially movable valve member disposed in the opening of the housing and configured to move axially relative to the valve housing between an open valve position and a closed valve position as a portion of the valve member is moved along an angled surface that is not normal to an axis of axial movement, wherein fluid is allowed to pass to a fluid consuming battery in the open valve position. 
     According to another aspect of the present invention, a battery is provided that includes a housing having one or more fluid entry ports for allowing passage of fluid, and a fluid consuming electrode disposed in the housing and in fluid communication with the one or more fluid entry ports. The battery also includes a valve housing in fluid communication with the fluid consuming electrode. The valve housing has an opening. The battery further includes a valve member disposed in the opening of the valve housing and configured to move axially relative to the valve housing between an open valve position and a closed valve position as a portion of the valve member is moved along an angled surface that is not normal to an axis of axial movement, wherein fluid is allowed to pass to the fluid consuming electrode in the open valve position. 
     These and other features, advantages, and objects of the present invention will be further understood and appreciated by those skilled in the art by reference to the following specification, claims, and appended drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG. 1  is a top view of a fluid consuming battery having a screw-type fluid regulator for controlling fluid entry, according to a first embodiment; 
         FIG. 2  is an exploded assembly view of the battery and fluid regulator of  FIG. 1 ; 
         FIG. 3  is an exploded assembly view of the battery of  FIG. 1 , including a cross-sectional view of the fluid regulator taken through line III-III of  FIG. 1 ; 
         FIG. 4  is a cross-sectional view of the fluid consuming battery having the fluid regulator in the closed valve position, taken through line IV-IV of  FIG. 1 ; 
         FIG. 5  is a cross-sectional view of the fluid consuming battery shown in  FIG. 1  with the fluid regulator shown with in the open valve position; 
         FIG. 6  is a top view of a fluid consuming battery having a screw-type fluid regulator, according to a second embodiment; 
         FIG. 7  is an exploded cross-sectional perspective view of the fluid regulator employed in the battery of  FIG. 6 ; 
         FIG. 8  is a cross-sectional view of the battery taken through line VIII-VIII of  FIG. 8  with the regulator shown in the closed valve position; 
         FIG. 9  is a cross-sectional view of the battery shown in  FIG. 6  with the regulator shown in the open valve position; 
         FIG. 10  is a perspective view of a device employing a battery and a linear slide fluid regulator, according to a third embodiment; 
         FIG. 11  is a top view of the linear slide fluid regulator shown in  FIG. 10 ; 
         FIG. 12  is a cross-sectional view taken through line XII-XII of  FIG. 11  with the linear slide fluid regulator shown in the closed valve position; and 
         FIG. 13  is a cross-sectional view taken through line XII-XII of  FIG. 11  with the slide valve fluid regulator shown in the open valve position. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Embodiments of this invention include a battery that includes an electrochemical cell that utilizes a fluid (such as oxygen or another gas) from outside the cell as an active material for one of the electrodes. The cell has a fluid consuming electrode, such as an oxygen reduction electrode. The cell can be an air-depolarized cell, an air-assisted cell, or a fuel cell. The battery also has a fluid regulator for adjusting the rate of passage of fluid to the fluid consuming electrode (e.g., the air electrodes in air-depolarized and air-assisted cells) to provide a sufficient amount of the fluid from outside the cell for discharge of the cell particularly at high rate or high power, while minimizing entry of fluids into the fluid consuming electrode and water gain or loss into or from the cell during periods of low rate or no discharge. 
     As used herein, unless otherwise indicated, the term “fluid” refers to fluid that can be consumed by the fluid consuming electrode of a fluid consuming cell in the production of electrical energy by the cell. The present invention is exemplified below by air-depolarized cells with oxygen reduction electrodes, but the invention can more generally be used in fluid consuming cells having other types of fluid consuming electrodes, such as fuel cells. Fuel cells can use a variety of gases from outside the cell housing as the active material of one or both of the cell electrodes. 
     Referring now to  FIGS. 1-5 , a fluid consuming battery  10  is shown employing a screw-type fluid regulator  30 , in accordance with a first embodiment. The fluid consuming battery  10  generally includes a fluid consuming cell  12  connected to the fluid regulator  30 . The fluid regulator  30  is embodied as a screw-type valve that regulates the flow of fluid, such as air containing oxygen, to a fluid consuming electrode of the fluid consuming cell  12 . The fluid regulator  30  includes a valve member  32  that is rotatable by a user to select between open and closed valve positions to control the flow of fluid (e.g., air) to the fluid consuming electrode of the battery cell  12 . The fluid consuming battery  10  may be integrated within or employed separately from any of a variety of electrically powered devices, such as hearing aids, music players, flashlights and other devices to supply operating electrical power. 
     In the exemplary embodiment, the fluid consuming battery cell  12  is an air-depolarized cell that uses a metal active material in the form of zinc as the negative electrode active material and has an aqueous alkaline (e.g., KOH) electrolyte. The fluid consuming battery cell  12  includes an electrochemical cell that utilizes a fluid (such as oxygen or another gas) from outside the cell as an active material for one of the electrodes. The battery cell  12  has a fluid consuming electrode, such as an oxygen reduction electrode. It should be appreciated that the fluid consuming battery cell  12  may contain an air-depolarized cell, an air-assisted cell or a fuel cell, and the cell and battery may have other shapes (such as button, cylindrical, and square) and sizes, according to various embodiments. 
     The air-depolarized cell  12  as best seen in  FIGS. 4 and 5  includes a cell housing which may include a first housing component and a second housing component, which may include a can  14  and a cover  16 , respectively, and may have shapes or sizes differing from what would otherwise be considered a can or cover. For purposes of example, the first housing component is hereinafter referred to the can  14 , while the second housing component is hereinafter referring to as cover  16 . The can  14  and cover  16  are both made of an electrically conductive material, but are electrically insulated from one another by means of a gasket  26 . Can  14  generally serves as the external positive contact terminal for the fluid consuming cell  12 , whereas cover  16  serves as the external negative contact terminal. The cell  12  further includes a first electrode  20 , which may be the fluid consuming electrode, referred to as an air electrode in the disclosed embodiment, a second electrode  22 , which may be the negative electrode (i.e., anode) and a separator  24  disposed between the first and second electrodes. The first electrode  20  is electrically coupled to can  14 , whereas the second electrode  22  is electrically coupled to cover  16 . 
     The can  14  generally includes a surface in which a plurality of fluid entry ports  18  are provided so that fluid (e.g., air) may pass to the interior of the cell housing so as to reach the fluid consuming electrode  20 . In the embodiment shown in  FIG. 2 , the can  14  has six (6) fluid entry ports  18  provided in the top surface of can  14 ; however, it should be appreciated that any of a number of fluid entry ports  18  of various sizes and shapes may be employed to allow fluid to pass to the fluid consuming electrode  20  through an air distribution layer  28 , which provides for more even distribution of air access across the adjacent surface for the fluid consuming electrode  20 . 
     The fluid regulator  30  regulates the amount of fluid that may pass from the outside environment, enter through the fluid entry ports  18 , and reach the fluid consuming electrode  20  of the battery cell  12 . As such, the fluid regulator  30  is engaged to the exterior surface of the can  14  such that the flow of air from the outside environment to entry ports  18  is controlled by the fluid regulator  30 . The fluid regulator  30  includes a valve housing shown in one embodiment as a plate  42  secured to the surface of the can  14 . Valve housing  42  has a threaded opening  44  with first threads  46  provided in the walls defining opening  44 . Additionally, at least one and preferably a plurality of air inlet openings  48  are formed in the valve housing  42  extending from the top surface to the bottom surface to allow fluid, such as air, to pass through the valve housing  42  when the fluid regulator  30  is in the open valve position. The fluid regulator  30  also includes a screw valve member  32  which generally includes an enlarged head  33  and a threaded screw shaft  34  having second threads  36  provided thereon. Second threads  36  are sized with a diameter and turn ratio to cooperatively engage first threads  46  within opening  44  of the plate  42 , such that the valve screw member  32  may be rotated within opening  44  of valve housing  42  to open and close the fluid regulator valve. 
     To assist in actuating the fluid regulator  30 , a lever  38  is provided on the head  33  of valve screw member  32  for easy engagement with a user&#39;s fingers. It should be appreciated that the fluid regulator  30  further includes an annular seal  40  disposed in a slot near the periphery on the bottom side of head  33  of screw member  32 . The seal  40  provides a sealed closure between the screw member  32  and valve housing  42  when in the closed valve position such that fluid flow through openings  48  is prevented when the valve is in the closed valve position. Additionally, a seal  50  is provided between the battery cell can  14  and the valve housing  42  to provide sealing engagement between the valve housing  42  and the can  14 . 
     In this embodiment, the screw-type fluid regulator  30  is operated by a user engaging lever  38  and rotating valve screw member  32  between the open and closed valve positions. The movable valve member  32  moves axially when rotated by moving along an angled surface of the first and second threads  46  and  36  that is not normal to the axis of axial movement. The angled surface also is not parallel to the axis of axial movement. In this embodiment, the surface along which the portion of the valve member is moved is a curved surface defined by the threads. 
     In  FIG. 4 , the fluid regulator  30  is shown in a fully closed valve position when the valve screw member  32  is rotated clockwise such that it is fully inserted within opening  44  so that the seal  40  provides a sealed closure against valve housing  42  to prevent fluid from passing through openings  48  between the outside environment and the battery cell  12 . To open the valve of the fluid regulator  30 , a user engages the lever  38  and rotates the valve screw member  32  counterclockwise such that the valve screw member  32  moves axially away from the valve housing  42  and battery cell  12  as seen in  FIG. 5 . When the screw member  32  is sufficiently rotated counterclockwise, the enlarged head  33  of screw member  32  and seal  40  are moved sufficiently axially away from the valve housing  42  so as to provide an unobstructed fluid flow passage  52  to allow fluid from the outside environment to pass through openings  48  and into the fluid consuming battery cell  12  by way of fluid entry ports  18 , such that the fluid consuming electrode  20  receives air or other fluid. While rotational to linear translation of screw member  32  is achieved by clockwise rotation to close the valve and counterclockwise rotation to open the valve, it should be appreciated that the rotational directions may be reversed. 
     It should be appreciated that by rotating the screw member  32  and thereby moving the screw member  32  axially relative to the valve housing  42 , the fluid regulator  30  effectively opens and closes the fluid flow passage  52  to respectively allow or prevent fluid from passing through openings  48  to the inside of the battery cell  12 . When the battery  10  is not in use, a user may rotate the valve screw member  32  clockwise to move the valve screw member  32  axially toward the valve housing  42  until seal  40  closes the fluid flow passage  52  to prevent fluid from reaching the battery cell  12 . Thus, it should be appreciated that an easy to use and cost effective screw-type valve fluid regulator  30  is provided for use on a battery cell  12  so as to provide for an enhanced battery construction. 
     Referring to  FIGS. 6-9 , a fluid consuming battery  110  is illustrated having a fluid regulator  130  assembled to the fluid consuming battery  12 , according to a second embodiment. The fluid regulator  130  provides a screw-type regulator valve that regulates the ingress and egress of fluid to the fluid consuming battery cell  12  based on user rotation of a valve screw member  132 . In this embodiment, the screw valve member  132  is generally shown having a head portion  133  at the upper end with a pair of opposing levers  138  extending therefrom to allow a user to engage and rotate the screw member  132 . The screw member  132  also has a screw portion  134  extending downward. The screw member  132  also includes a central cavity  137  extending from the top head portion  133  to a plurality of openings  135  formed in a lower side wall of the screw portion  134 . The screw portion  134  also includes first threads  136  formed on the outer cylindrical wall. In this configuration, fluid is allowed to pass from the outside environment through the cavity  137  and out the openings  135  to the battery cell  12  when the fluid regulator  130  is in the open valve position. 
     The fluid regulating system  130  also includes a valve housing  142  shown as a plate having an opening  144  with second threads  146  formed in the side walls of the opening  144 . Second threads  146  are of a size and shape configured to matingly engage first threads  136  of the screw portion  134  of screw member  132 . The valve housing member  142  is sealingly engaged to the bottom side of can  14  of the battery cell  12  by way of a seal  150 . It should be appreciated that the valve housing  142  may be secured or fastened to the can  14  by way of brackets, fasteners, glue or other structural connection for example. 
     Referring to  FIG. 8 , the fluid regulator  130  is shown in the open valve position such that fluid (e.g., air) is able to flow from the outside environment through the cavity  137  and openings  135  such that the fluid passes through the screw member  132  into opening  144  shown by fluid flow path  152  to fluid consuming battery cell  12 . The fluid passing through the valve on fluid flow path  152  then enters fluid entry ports  18  to reach the fluid consuming electrode  20  of the battery cell  12 . In the open valve position, the screw member  132  is displaced axially from the plate  142  and battery cell  12  such that fluid is able to pass through the regulator valve to the battery cell  12 . The movable valve member  132  moves axially when rotated by moving along an angled surface of the first and second threads  136  and  146  that is not normal to the axis of axial movement. The angled surface also is not parallel to the axis of axial movement. In this embodiment, the surface along which the portion of the valve member is moved is a curved surface defined by the threads. 
     To close the valve, an operator may rotate the screw member  132  by engaging levers  138  and turning screw member  132  clockwise such that the first and second threads  136  and  146  translate rotational movement of the screw member  132  axially toward the valve housing  142  and battery cell  12 . Sufficient rotation of the screw member  132  will cause the angled bottom end  175  of the screw portion  134  to engage the corner  177  at the reduced diameter portion of the valve housing  142  so as to close off the air flow path  152  between the screw member  132  and valve housing  142 . This movement causes the regulator valve to close, such that fluid is not able to pass into the battery cell  12 . It should be appreciated that the screw member  132  may be rotationally actuated to open the regulator valve to allow air to flow to the battery cell  12  when continued operation of the battery  10  is desired. 
     Accordingly, the fluid consuming battery  110  employing the second embodiment of a screw-type fluid regulator  130  advantageously provides for a low cost, easy to use regulator valve for regulating the flow of fluid to a battery consuming cell  12 . The fluid regulator  130  is relatively easy to use and avoids the need for complex components. 
     Referring to  FIGS. 10-13 , a device  280  is shown employing a fluid consuming battery  210  and a slide-type fluid regulator valve  230 , according to a third embodiment. The fluid regulator valve  230  includes a valve housing  242  shown assembled to the device  280 . The device  280  may include an electrically operated device, such as a music player, cell phone, flashlight, laptop computer, hearing aid or other electronic devices. The device  280  has a battery compartment configured having a size and shape and electrical contacts adapted to receive a fluid consuming battery, such as an air-depolarized battery cell  12  having fluid entry ports  18  and a fluid consuming electrode  20  as described above. Thus, the battery cell  12  may be disposed within the battery compartment and covered by the regulator valve housing  242 . 
     The fluid regulator  230  in this embodiment includes a linear slide valve member  232  that is engageable and activated by a user from a closed valve position to an open valve position. The slide valve member  232  has a seal  245  that forms a sealed closure with the valve housing  242  when in the closed valve position. The slide valve member  232  follows a ramped surface on an inclined plane generally defined by an angled slot  290  formed in a side wall of the valve housing and engaged thereto with pins  292  such that the linear slide valve member  232  and seal  245  move axially away from the lower plate of valve housing  242  and battery cell  12  when sliding on the ramped surface from the closed valve position to the open valve position. In this embodiment, the slide valve  232  moves axially when slid by moving along an angled straight surface of the ramped surface that is not normal to the axis of axial movement. The ramped surface also is not parallel to the axis of axial movement. 
     As seen in  FIG. 12 , the regulator valve  30  is shown in the closed valve position with the linear slide valve member  232  at the bottom of the ramped surface in the closed valve position. In this position, fluid is prohibited from flowing from the outside environment to the fluid consuming battery cell  12  due to the seal  245 . To open the valve, a user engages the slide valve member  232  to move the slide valve member  232  from the bottom of the ramped surface up the ramped surface to the open position as shown in FIG.  13 . In doing so, pins  292  slide in slot  290  so that the slide valve member  232  and seal  245  move axially away from plate  242  and battery cell  12  so as to provide air flow path  252  leading to fluid entry ports  18  in the battery cell  12 . Accordingly, linear actuation of the slide valve member  232  translates to axial movement of the valve  232  and seal  245  to open and close the linear slide valve member. It should be appreciated that the amount of axially movement achieved with the linear movement of slide valve member  232  may depend upon the distance and the angle of the slope of the straight ramped surface. By providing a ramped surface, a small amount of linear movement may pull the slide valve member  232  and seal  245  away from the lower plate of the valve housing  242  to allow for fluid to flow through multiple paths into the fluid entry ports  18  of battery cell  12 . While a pin and slot arrangement are shown for providing the ramped surface, it should be appreciated that other matingly engaged surface connections may be provided to move the slide valve member  232  axially during linear movement thereof. 
     The fluid regulator can be mounted directly on the cell housing, as described above, incorporated into a separate battery casing, such as the casing of a battery containing a plurality of fluid consuming cells, or incorporated into a compartment in a device in which the fluid consuming battery is installed. 
     In addition to a fully opened open valve position, the fluid regulator can also have one or more intermediate open valve positions in which the fluid flow is partially restricted to meet less demanding power requirements than in the fully opened open valve position. 
     Accordingly, the various embodiments of the screw-type and linear slide fluid regulators advantageously provide for an easy to use and cost-effective regulator valve for controlling fluid, such as air, to a fluid consuming battery cell. The fluid regulators advantageously consume a small volume, having a relatively low height, few components, few complex fabricated components, and a relatively easy to use design that is cost affordable, without the need for complex spring bias. Additionally, the fluid regulators are easily actuatable by a user manually, or may be actuated with an actuator, according to other embodiments. 
     While a screw-type and a linear slide embodiment of the valve regulator  30 ,  130  and  230  have been shown and described herein, it should be appreciated that other fluid regulators may be employed without departing from the spirit of the present invention. 
     While the invention has been described in detail herein in accordance with certain preferred embodiments thereof, many modifications and changes therein may be affected by those skilled in the art without departing from the spirit of the invention. Accordingly, it is our intent to be limited only by the scope of the appending claims and not by way of the details and instrumentalities describing the embodiments shown herein.