Abstract:
An apparatus and method for marking a battery as charged or uncharged, comprising a manually changeable label attached to a battery in a pocket region defined about a battery positive contact button, wherein the label may be changed by a user to indicate either charged or uncharged battery status.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
   This application claims the benefit of U.S. Provisional Application Ser. No. 60/491,659, filed Jul. 29, 2003. 

   BACKGROUND OF THE INVENTION 
   There is a need for a charge indicator that can be used on common nickel metal hydride cylindrical rechargeable batteries, also known as “NIMH cells.” Typical sizes and styles are known as AAA, AA, C, D and 9-volt style package. These batteries are typically manufactured in Nickel Metal Hydride (Nimh) and Nickel Cadmium (Nicad). These rechargeable batteries can replace their counterparts being known as zinc and alkaline and can be recharged many times over, typically one thousand times, thus saving the user a considerable amount of expense for battery power over the life of these rechargeable types. 
   Utilizing these types of batteries presents the problem of keeping track of the charged batteries, and distinguishing them from discharged batteries. Prior art approaches include battery holder packs that can be marked charged and discharged, wherein a user needs to keep the batteries in these holders to identify their state. There are patents (such as U.S. Pat. No. 6,483,275) and designs that have the batteries themselves indicate their status of charge, a technique that requires circuits onboard and the like. 
   There is a growing use of battery power in the world for equipment like digital cameras that use a great deal of power and also need the portability of a small powerful universal battery. The market is growing very quickly. Battery manufacturers, as well as battery charger manufactures, have realized this and it would appear that this need for vast amounts of renewable power will continue for some time. 
   There is a need to identify a battery&#39;s state of charge so as not to place a discharged battery in with freshly charged batteries. This is also not wise due to discharging among themselves to level out the charge state of the group being used in the equipment. What is needed is a way to easily mark each individual battery before and after use in the equipment. It is really not necessary to know the exact state of the battery charge in most cases. The equipment in use typically has built in charge indicators, such as digital cameras to identify the level of the batteries. A typical user only cares to know that the batteries have been fully charged and that they are discharged after removing them from the equipment in use. This is why each battery needs to have an indicator. Typical charge indicators look at voltage levels, but NIMH batteries have a very distinctive discharge curve that keeps the battery at a given voltage level just before running out of power in an abrupt manner. Due to the sudden power drop-off characteristic of NIMH and Nicad batteries, prior art self-testing systems incorporated within or onto the battery cannot reliably indicate to a user whether the battery has a full usable charge. 
   SUMMARY OF THE INVENTION 
   An apparatus and method for marking a battery as charged or uncharged, comprising a manually changeable label attached to a battery in a pocket region defined about a battery positive contact button, wherein the label may be changed by a user to indicate either charged or uncharged battery status. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of typical rechargeable batteries. 
       FIG. 2  is a perspective view of another typical rechargeable battery altered to accept the present invention. 
       FIG. 3  is a perspective view of one element of the present invention. 
       FIG. 4  is a perspective view of the rechargeable battery of  FIG. 2  incorporating the element of  FIG. 3 . 
       FIG. 5  is a perspective view of another element of the present invention. 
       FIG. 6  is a perspective view of the rechargeable battery of  FIG. 4  incorporating the element of  FIG. 5 . 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The present invention is a system and method to provide an indicator with each battery as they are being manufactured for only pennies cost to the manufactures, yet a wealth of convenience to end users by efficiently providing a way of knowing the state of each battery. This concept could potentially increase manufacturers&#39; sales a great deal through the simplicity, low cost and novel method used for such an indicator. 
   Referring now to  FIG. 1 , the rechargeable batteries  10  and  12  in discussion are manufactured in typically the same manor. The present invention takes advantage of spaces in the top portions  30  and  32  of each battery  10  and  12 , respectively, where the can bodies  20  or  22  are crimped to top portion gaskets  40  and  42  of each cell  10  and  12 . In this area, the two polarities of the battery are separated by the gaskets  40  and  42 , which act as a seal and an insulator, as is well known in the art. 
   Referring now to  FIG. 2 , according to the present invention, the gasket  40  is removed to create a pocket  246  around the contact positive button portion  248  of the top area  30  of the battery  10 . This top area  30  is where venting is done by the battery  10 , and most manufacturers typically place an insulating cardboard disc  40  on the top and shrink a portion of the outer battery label  20  around a portion of the disc  40  to prevent shorting of the battery poles by end users, as well as to improve appearance. 
   Inherently, there is a pocket space  246  left under the prior art disc  30 , and referring now to  FIGS. 3 through 6 , the present invention utilizes this circular pocket space  246  to provide space for application of an improved insulating indicator  300 . It is important to note that batteries are typically designed around standards for size, and manufacturers use the maximum amount of space available for the battery material to achieve the most powerful batteries they can for a package size. Taking space for things like indicators and reducing capacity would not be acceptable in the market. Thus, it is an advantage of the present invention that the application space utilized is a by-product of the manufacturing process and does not interfere with the function or performance aspects of the battery being manufactured. 
   The indicator  300  is preferably made up of two components: a top modified insulating disc  304  and a bottom indicator  302 . The disc  304  has a disc central post aperture  305  and indicator  302  has an indicator central post aperture  303  formed to encircle the contact positive button portion  248 . The insulating disc  304  may have similar material characteristics as used in current battery manufacturing. One embodiment is cardboard. What is new is that an indicator aperture  306  is formed in the disc  304 . The bottom indicator  302  is a plastic or other non-conductive disc that is placed in the void area  246  under the insulating disc  304 , preferably as the battery  10  is being finished. This indicator  302  has two distinct markings  310  and  312 . It is preferred that the marking involve two contrasting colors, for example, a red ink area  310  and a green ink area  312 . 
   The disc  304  also forms an engaging aperture  320 , preferably on the other side, across the disc from the aperture  306 . An engaging element  322  on the indicator  302  is aligned with the engaging aperture  320 . Exemplary engaging element  322  embodiments include a hole aperture punched in the indicator  302  (not shown) and a raised knob  324  preferably formed from injection molding or press forming. The insulating disc  304  is now not just a plain flat round piece of cardboard, but a disc that has a unique indicator aperture  306  punched in it for viewing of the indicator disc  302  underneath. 
   With the indicator  302  residing in the cavity  246  under the uniquely punched insulating disc  304 , a user is now able to see either a red or a green dot  330  through the indicator aperture  306 . Across the insulating disc  304  is either a hole (not shown) or the raised knob  324  in the bottom indicator  302  that protrudes up through the engaging aperture  320 . This knob  324  now becomes an activator, which can rotate along the engaging aperture  320 , which is preferably an arch slot punched in the top cardboard insulating disc  304 . The reason for the rotation is to allow the user the ability to rotate the bottom indicator  302  from side to side and cause either the red area  310  dot or the green area  312  to appear as a colored “dot”  330  in the aperture  306  window as punched in the top cardboard insulating disc  304 . 
   It is preferable to use a raised embossed portion or injection molded part  324  rather than a flat disc with a hole for adjusting (not shown). A flat disc could be less expensive but would require a tool, like a pen, to rotate the disc. It would also not have the stops inherent of a raised section like button on the bottom disc and would also act as stops in the arch region, so as not to become lost in a continuous circular rotation under the top disc. Finally, the battery label is applied, and captures the two discs in the same way the label captures the one in typical battery production. 
   Although the present invention requires human intervention, and does not really tell the actual status of the battery  210 , it is preferable over automated prior art indicators. A user of the battery  210  simply rotates the indicator  302  after charging the battery  210  and is now aware that they have performed the charge operation. The battery  210  can be transported in any fashion desired and in any holder or camera pack without regard to keeping these separate from discharged batteries. After using the batteries in the equipment, the user simply rotates the indicator  302  to the discharged position and will be aware of its condition so as not to mix this battery  210  with other charged batteries. The design and concept are just as robust and cost compliant as the design of the ordinary battery, and should last the life of the rechargeable battery itself. 
   As for the implementation of smart batteries that monitor themselves, this approach is not cost effective. Some human intervention, such as rotating the indicator  302  to change the status condition of the battery  210 , is very simple and cost effective. 
   AFTERMARKET OPTION. Knowing that there may be some lack of interest for large battery manufacturers to change their processes and/or feel that the value of implementing the indicator may cost too much, the present invention may also be embodied as an optional “stick on” label style of indicator. The way it would work would be a circular ring type label (not shown) with a clear hole in the center for the positive button of the battery to protrude through. The label would be made in three pieces; one would be a bottom that had an adhesive on it to bond to the top of the battery cell. The second layer would be similar to the rotating indicator disc  302  with an embossed projection  324  on it to rotate the disc and the two red and green color areas  310  and  312  screen printed on it opposite the embossed projection  324 . The third layer would be a top insulating disc  304  with the slot  320  for rotating the disc and window  306  for viewing indicator dot  330 . The end user could apply this label to any number of batteries they desired and it can be manufactured to accommodate all cell sizes. 
   The present invention can also be made to accommodate rectangular 9-volt batteries by making the indicator  302  a rectangular laminated label rather than a circular label. This one would be placed on the bottom of 9-volt type batteries but could also become generic and be used for many other kinds of rechargeable batteries, such as cordless drill batteries and the like. The market for the aftermarket label could exceed the OEM style label in places like do it yourself home stores. 
   While preferred embodiments of the invention have been described herein, variations in the design may be made, and such variations may be apparent to those skilled in the art of battery manufacture and charge indicating systems, as well as to those skilled in other arts. The materials identified above are by no means the only materials suitable for the manufacture of the invention, and substitute materials will be readily apparent to one skilled in the art. The scope of the invention, therefore, is only to be limited by the following claims.