Patent Description:
Electrochemical cells, often simply called batteries, are commonly used as electrical energy sources. Small batteries are especially useful in powering consumer products. Small batteries come in a variety of cell types. Common small battery cell types include AAA, AA, B, C, D, 9V, CR2, and CR123A. Other types of small batteries known as button cells (also including wider cells sometimes referred to as coin cells) are frequently used to power a variety of products including but not limited to watches, cameras, calculators, key-less entry systems for vehicles and the like, laser pointers, glucometers, etc..

<FIG> illustrates the construction of a representative button cell <NUM> comprising a cathode <NUM> disposed within a cathode can <NUM> and an anode <NUM> disposed within an anode cup <NUM>. A separator <NUM> physically separates and electronically insulates the anode <NUM> from the cathode <NUM>. An insulating gasket <NUM> serves to seal the cell to prevent electrolyte loss and to prevent ingress of ambient atmospheric components into the cell and electronically insulate the cathode can <NUM> from the anode cup <NUM>. Button cells usually have a long service life, for example, typically well over a year in continuous use in a wristwatch. In addition, most button cells have low self-discharge such that they hold their charge for relatively long times when not placed under load.

While button cell batteries are common in many portable consumer electronic devices, the size, shape, and appearance of these batteries, particularly coin cells having a diameter of <NUM> such as CR2016 lithium cells and CR2032 lithium cells, can pose dangers, particularly to infants, toddlers, and pets. These dangers can result in bodily harm, especially if the cell is swallowed unbeknownst to others around. And some of these button cell batteries can pose a relatively greater danger than others, which consumers may not fully appreciate. For example, 3V coin cells batteries such as CR2016 3V lithium cells and CR2032 3V lithium cells, which are based on lithium-manganese dioxide chemistry, are sized such that they readily can become lodged in a human throat and thus cause electrolysis of body fluids and/or burning wet esophageal/organ tissue, for example, if swallowed. Of course, such batteries can also cause significant gastric distress if successfully swallowed.

<CIT> describes a coin-type battery (<NUM>) having an exterior body including a case (<NUM>), a sealing plate (<NUM>), a gasket (<NUM>), and a separator (<NUM>). The case (<NUM>) includes a bottom plate portion (1a) and side portions (1b) rising from the periphery of the bottom plate portion (1a). The sealing plate (<NUM>) has a top plate portion (6a) and a peripheral portion (6b) extending from the top plate portion (6a) to the inside of the side portion (1b) of case (<NUM>). A part of the gasket (<NUM>) seals the gap between the case (<NUM>) and the sealing plate (<NUM>) by being interposed between the side portion (1b) of the case (<NUM>) and the peripheral portion (6b) of the sealing plate (<NUM>), as discussed in paragraph [<NUM>] and <FIG> of the reference. The side end (1t) of the case (<NUM>) and the outer surface exposed portion (5t) of the gasket (<NUM>) are covered with an organic coating (<NUM>) that absorbs liquid and expands.

A battery with a safety mechanism adapted to protect against tissue damage and/or electrolysis, as specified in claim <NUM>, is provided. The battery comprises a housing comprising first and second poles. At least one electronic conductor is electronically coupled to one of the first and second poles. A spacer comprising an electronically insulating material is provided between the electronic conductor and the other of the first and second poles such that electronic coupling between the electronic conductor and the other of the first and second poles is prevented. The spacer is capable of undergoing a physical change in the presence of an aqueous solution such that electronic coupling between the electronic conductor and the other of the first and second poles can occur.

An additional exemplary battery with a safety mechanism adapted to protect against tissue damage and/or electrolysis is also provided. The battery with a safety mechanism comprises a housing comprising first and second poles, an electronic conductor and first and second spacers. The first and second spacers comprise an electronically insulating material. The first spacer is disposed between a first pole of the battery and the electronic conductor and the second spacer is disposed between a second pole of the battery and the electronic conductor, with the electronic conductor being disposed between and in contact with the first and second spacers. The spacers are capable of undergoing a physical change in the presence of an aqueous solution, and the electronic conductor are adapted to establish electronic contact with both the first and second poles in the presence of the aqueous solution.

While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter, which is regarded as forming the present invention, the invention will be better understood from the following description taken in conjunction with the accompanying drawings. The figures described below depict various aspects of the batteries disclosed herein. It should be understood that each figure depicts exemplary aspects of the batteries a safety mechanism adapted to protect against tissue damage and/or electrolysis disclosed herein.

Electrochemical cells, or batteries, may be primary or secondary. Primary batteries are meant to be discharged, e.g., to exhaustion, only once and then discarded. Primary batteries are described, for example, in<NPL>). Secondary batteries are intended to be recharged. Secondary batteries may be discharged and then recharged many times, e.g., more than fifty times, more than a hundred times, or more than a thousand times. Secondary batteries are described, e.g., in<NPL>). Batteries may contain aqueous or non-aqueous electrolytes. Accordingly, batteries may include various electrochemical couples and electrolyte combinations. Consumer batteries may be either primary or secondary batteries. However, because of the electrical charges stored in the batteries and because of the exposed poles, it is advantageous to protect consumer batteries, in particular small consumer batteries, against harming consumers when exposed to wet tissues. In particular, it is advantageous to protect batteries against exposing consumers to electrolysis or burns, both of which can occur when a battery is swallowed, for example. In this regard, if the positive and negative poles of a battery are exposed to wet bodily fluids, electrolysis of water can occur and result in the development of hydroxide ions and burning of tissues adjacent the negative pole, as well as potentially causing direct oxidation of tissues, particularly those tissues that are adjacent the positive pole (or cathode can). In addition, significant oxidation of the cathode can itself may lead to the formation of holes therein and thereby allow the toxic contents of the battery to be released. The present application provides safety mechanisms for shorting batteries in the presence of an aqueous solution. By shorting the batteries in the presence of an aqueous solution, the disclosed safety mechanisms advantageously reduce the cell voltage of a battery that is swallowed and thereby can effectively prevent tissue damage and other deleterious effects caused by the uncontrolled discharge of a swallowed battery.

A battery with a safety mechanism adapted to protect against tissue damage and/or electrolysis is provided. The battery includes a battery housing comprising first and second poles. At least one electronic conductor is electronically coupled to or in electronic contact with one of the first and second poles. It should be noted that the terms "electronically coupled" and "electronic contact" are used herein interchangeably to describe a relationship in which electron flow between the listed components can occur. The electronic conductor may be electronically coupled to one of the first and second poles because it is in direct physical contact therewith. Alternatively, there can be one or more additional intervening electronically conducting materials between the electronic conductor and the one of the first and second poles.

A spacer comprising an electronically insulating material is provided between the electronic conductor and the other of the first and second poles such that electronic coupling between the electronic conductor and the other of the first and second poles is prevented. The spacer is capable of undergoing a physical change (including but not limited to undergoing a chemical change leading to a change in physical properties) in the presence of an aqueous solution such that electronic coupling between the electronic conductor and the other of the first and second poles can occur.

Generally, the present disclosure provides batteries that are capable of being shorted, mechanically and/or electronically, by electronically coupling both battery poles or forming an electronic connection across both battery poles. The electronic connection across the positive and negative battery poles is formed only after the battery is exposed to a "safety condition", which refers to an ambient condition the battery encounters when becoming lodged in the throat of a person, an infant, or a pet animal. In these situations, when a person or infant or pet animal swallows a battery, the battery can be contacted with saliva, stomach fluids, or other aqueous fluids. Thus, the batteries with safety mechanisms adapted to protect against tissue damage and/or electrolysis are constructed and designed to short when in the presence of an aqueous solution. The resulting short-circuit is able to drop the voltage of the battery to below a desired threshold level to thereby reduce and/or effectively prevent the electrolysis of water and the accompanying formation of harmful electrochemically-generated ions (e.g., hydroxide ions). The desired threshold levels can vary, but in some examples detailed herein, the cell can be advantageously shorted to below <NUM>. 5V, including below <NUM>. 4V, below <NUM>. 3V, below <NUM>. 2V, below <NUM>. 1V, below <NUM>. 1V, and even to about 0V. Under "normal use conditions", such as when the battery is not in use, for example, when the battery is being stored or transported, or when the battery is in operation in an electronic device, formation of the electronic connection does not occur and battery shorting is avoided.

In one embodiment, a battery according to the disclosure includes an electronic conductor that is initially in electronic contact with only one of the first and second poles of the battery. A spacer comprising an electronically insulating material prevents the electronic conductor from establishing electronic contact across both of the battery poles under normal use conditions (i.e., before the battery is contacted with an aqueous solution). On the other hand, when the battery is exposed to or contacted with an aqueous solution such as saliva, stomach fluids, water, or other aqueous fluid, the electronically insulating material can undergo a physical change, for example, the electronically insulating material can dissolve because it is soluble in the aqueous fluid. The electronic conductor is biased towards electronic contact with the other pole of the battery, but the resistive force of the spacer is greater than or equal to the biasing force of the electronic conductor under normal use conditions. After substantial dissolution of the electronically insulating material, however, there is substantially no such resistive force and the electronic conductor can establish electronic contact with the other pole of the battery, thereby short-circuiting the battery. The electronic conductor may be biased, for example, during crimping of the cathode can (or an extension thereof) and/or during crimping of an electronic conductor that is a separate discrete component from the cathode can.

In another example, a battery according to the disclosure also includes an electronic conductor that is initially in electronic contact with only one of the first and second poles of the battery. A spacer comprising an electronically insulating material prevents the electronic conductor from establishing electronic contact across both of the battery poles under normal use conditions (i.e., before the battery is contacted with an aqueous solution). On the other hand, when the battery is exposed to or contacted with an aqueous solution such as saliva, stomach fluids, water, or other aqueous fluid, the electronically insulating material can undergo a physical change, for example, the electronically insulating material can swell and/or soften in the presence of the aqueous fluid because it is comprised of a polymer that swells when exposed to the aqueous solution. The electronic conductor is biased towards electronic contact with the other pole of the battery, but the resistive force of the spacer is greater than or equal to the biasing force of the electronic conductor under normal use conditions. After swelling and/or softening of the electronically insulating material, however, the spacer resistive force is significantly decreased and mechanical deformation, strain, or displacement of the spacer may be achieved because the biasing force of the electronic conductor "overcomes," strains, or displaces the electronically insulating material of the spacer and thereby establishes an electronic connection between the two poles and short-circuits the battery. In one refinement, the electronically insulating material is a hydrogel which, in the presence of an aqueous fluid, forms a gel that is incapable of resisting the biasing force provided by the electronic conductor. The electronic conductor may be biased, for example, during crimping of the cathode can (or an extension thereof) and/or during crimping of an electronic conductor that is a separate discrete component from the cathode can.

By way of example, the electronic conductors herein may be formed of metals, for example, the electronic conductors may be formed of any suitable electronic conducting materials. Suitable electronic conducting materials for forming the electronic conductors include but are not limited to (i) metal alloys including but not limited to steels such as stainless steel, nickel-plated steel, or zinc-plated steel, (ii) conductive ceramics including but not limited to carbides, oxides, nitrides, and combinations of the foregoing, (iii) conductive polymers, (iv) conductive composites, and any combinations thereof. The electronic conductor may be biased, for example, during crimping of the cathode can (or an extension thereof) and/or during crimping of an electronic conductor that is a separate discrete component from the cathode can.

The electronic conductors disclosed herein generally have a resistivity value of less than about <NUM>×<NUM>-<NUM> ohm·cm at <NUM>, or less than <NUM>×<NUM>-<NUM> ohm·cm at <NUM>, or from about <NUM>×<NUM>-<NUM> ohm·cm at <NUM> to about <NUM>×<NUM>-<NUM> ohm·cm at <NUM>. In some examples, the resistance of the electronic conductor is less than <NUM> Ohms, less than <NUM> Ohms, or less than <NUM> Ohms, for example, the resistance may be about <NUM> Ohms, about <NUM> Ohms, or about <NUM> Ohm. In some examples, the resistance of the electronic conductor is from about <NUM> Ohms to about <NUM> Ohms.

The resistance of the electronically insulating material is always greater than the resistance of the electronic conductor. In some examples, the resistance of the electronically insulating material is greater than <NUM> MOhms, greater than <NUM> MOhms, greater than <NUM> MOhms, greater than <NUM> MOhms, or greater than <NUM> MOhms, for example, the resistance of the electronically insulating material may be about <NUM> MOhm, about <NUM> MOhms, about <NUM> MOhms, or about <NUM> MOhms. In some examples, the resistance of the electronic conductor is from about <NUM> MOhms to about <NUM> MOhms.

The electronically insulating material of the spacer can be formed of any number of electronically insulating materials capable of undergoing a physical change (including but not limited to electronically insulating materials that undergo a chemical change leading to a change in physical properties) when in the presence of water including but not limited to suitable water-softenable materials, suitable water-soluble, and/or water-swellable materials. The term "water-softenable" as used herein refers to a material having a Young's modulus that decreases in the presence of an aqueous solution. Useful water-softenable materials have a Young's modulus that is sufficiently high to provide a resistive force greater than a biasing force of an electronic conductor under normal use conditions. Useful water-softenable materials, after being in the presence of an aqueous solution, also have a Young's modulus that is sufficiently low to allow the material to sufficiently deform when the biasing force of the electronic conductor is applied thereto, such that electronic coupling between the electronic conductor and the other of the first and second battery poles can be established. Useful water-softenable materials also generally have a Young's modulus that decreases to a range between. <NUM> and <NUM> GPa after being in the presence of an aqueous solution. Various testing systems can be used to determine the elastic modulus, for example, the <NUM> servohydraulic testing system available from Instron. The water-softenable material may be a water-soluble material. Useful water-soluble materials have a solubility in water of greater than <NUM>/L, greater than <NUM>/L, greater than <NUM>/L, or even greater than greater than <NUM>/L. Useful water-swellable materials generally are able to absorb more than <NUM> wt. % in pure water, preferably at least <NUM>% by weight in water. Useful water-swellable materials, after being in the presence of an aqueous solution, allow the material to sufficiently deform when the biasing force of the electronic conductor is applied thereto, such that electronic coupling between the electronic conductor and the other of the first and second battery poles can be established.

The electronically insulating material may be present in an amount between <NUM> wt. % and <NUM> wt. %, for example between <NUM> wt. % and <NUM> wt. %, between <NUM> wt. % and <NUM> wt. %, and/or between <NUM> wt. % and <NUM> wt. %, based on the weight of the spacer (i.e., based upon the weight of the solids used to provide the spacer). Any number of water-softenable, water-soluble, and/or water-swellable polymers may be used, alone or in combination, to form the spacer. Non-limiting examples of water-soluble, water-soluble, and/or water-swellable materials include but are not limited to sugar, polyethers such as polyethylene glycols (PEGs) and polyethylene oxides (PEO), polyacrylic acids (PAA), polyamides (PA), polyacrylates, polyvinyl alcohols and modified polyvinyl alcohols, acrylate copolymers, polyvinyl pyrrolidone, pullulan, gelatin, carboxymethyl cellulose (CMC), hydroxylpropylmethyl cellulose (HPMC), hydroxypropylcellulose, polysaccharides, natural polymers including, but not limited to, agar, guar gum, xanthan gum, locust bean gum, carrageenan, and starch, modified starches including, but not limited to, ethoxylated starch and hydroxypropylated starch, copolymers of the foregoing, salts thereof, and combinations of any of the foregoing. The water-softenable, water soluble and/or water-swellable material preferably is a biologically inert material, with no toxicity or little toxicity.

Benign solids such as NaHPO<NUM>, sodium chloride (NaCl), potassium chloride (KCl), baking soda, sugar, sugar-like substances, and citric acid optionally can be included in combination with the electronically insulating material so as to provide the spacer. The benign solids may be present in an amount between <NUM> wt. % and <NUM> wt. %, for example between <NUM> wt. % and <NUM> wt. %, between <NUM> wt. % and <NUM> wt. %, and/or between <NUM> wt. % and <NUM> wt. %, based on the weight of the spacer (i.e., based upon the weight of the solids used to provide the spacer).

<FIG> illustrate a battery <NUM>, which may be any type of primary or secondary battery and which is a coin cell type battery in the illustrated example. The battery <NUM> includes a battery housing surrounding the battery. The battery housing comprises a cathode can <NUM> and an anode cup <NUM>. A cathode <NUM> is disposed in the cathode can <NUM> and an anode <NUM> is disposed in the anode cup <NUM>. The cathode <NUM> and the anode <NUM> are separated electronically by a separator <NUM> within the battery <NUM>. Each of the cathode can <NUM> and the anode cup <NUM> forms a different pole of the battery <NUM>, with the cathode can <NUM> forming a positive pole and the anode cup <NUM> forming a negative pole.

The cathode <NUM> and the anode <NUM> are spaced apart by an insulating separator <NUM> extending across the lateral extent of the cathode <NUM>, e.g., substantially across a diameter of the battery <NUM>. The insulating separator <NUM> is fabricated from a material capable of freely conducting ions there through. An insulating gasket <NUM> electronically isolates the cathode can <NUM> from the anode cup <NUM>, the insulating gasket <NUM> preventing any part of the anode cup <NUM> from contacting the cathode can <NUM> and sealing the battery <NUM> to prevent electrolyte loss.

In the illustrated embodiment, the insulating gasket <NUM> extends into the cathode can <NUM> and entirely surrounds the anode cup <NUM> such that it cannot contact the cathode can <NUM>, but a reverse configuration in which the anode cup <NUM> surrounds the cathode can <NUM> and the insulating gasket <NUM> extends into the anode cup <NUM> and entirely surrounds the cathode can <NUM> may also be used. It should be understood that while each of the illustrated embodiments expressly shown herein (including as shown in <FIG>, <FIG>, <FIG>, <FIG>) includes the insulating gasket <NUM> (or corresponding reference no. ) extending into the cathode can <NUM> (or corresponding reference no. ) and entirely surrounding the anode cup <NUM> (or corresponding reference no. ) such that it cannot contact the cathode can <NUM> (or corresponding reference no. ), batteries with safety mechanisms in which the reverse configuration is used are contemplated.

The battery <NUM> further includes an exemplary safety mechanism adapted to protect against tissue damage and/or electrolysis according to the disclosure, the safety mechanism including an electronic conductor <NUM> extending entirely or partially around an outer edge of the cathode can <NUM>. The electronic conductor <NUM> may be formed of a metal, for example, a metal alloy material, as described above. The electronic conductor <NUM> includes an attaching segment <NUM> that is fixedly mounted to an outer surface of the cathode can <NUM>. The electronic conductor <NUM> may be mounted to the cathode can by any suitable interconnection. For example, the attaching segment <NUM> may be attached via an interference fit with a groove (not shown) along the exterior wall of the cathode can <NUM> for a mechanically secure attachment. In other examples, the attaching segment <NUM> may be attached to the exterior side wall of the cathode can <NUM> by application of an adhesive or by forming a welding joint.

In the reverse configuration (not shown, briefly described above) in which the insulating gasket <NUM> extends into the anode cup <NUM> and surrounds the cathode can <NUM> such that it cannot contact the anode cup <NUM>, the electronic conductor <NUM> extends entirely or partially around an outer edge of the anode cup <NUM> and may be secured thereto as described in connection with the cathode can <NUM> above.

As illustrated in <FIG>, the attaching segment <NUM> of the electronic conductor <NUM> is electronically coupled to the cathode can <NUM>. In the illustrated form, the electronic conductor <NUM> is in direct physical contact with the cathode can <NUM>. The electronic conductor <NUM> further includes a grounding segment <NUM> extending from the attaching segment <NUM>. Typically, the grounding segment <NUM> extends in an orthogonal or substantially orthogonal direction relative to the attaching segment <NUM>.

The grounding segment <NUM> is spaced from the anode cup <NUM> during normal operation of the battery <NUM>, so as not to electronically couple the positive and negative poles and thereby short the battery <NUM> during normal operation of the battery <NUM>. In the illustrated example, the spacing between the grounding segment <NUM> and the anode cup <NUM> is achieved by providing a spacer <NUM> comprising an electronically insulating material between the grounding segment <NUM> and the anode cup <NUM>. As illustrated in <FIG>, the spacer is disposed between an overhang portion of the grounding segment <NUM> and the other of the first and second poles, here the anode cup <NUM>, such that the grounding segment <NUM> of the electronic conductor <NUM> is not electronically coupled to the anode cup <NUM> (and thus the negative pole of the battery <NUM>) when the spacer <NUM> is present such as during normal use conditions. The spacer <NUM> may extend to or even beyond a distal overhang portion of the grounding segment <NUM>.

The spacer <NUM> may comprise a material capable of undergoing a physical change, e.g., by dissolution after being exposed to a safety condition, typically, saliva, stomach fluids, or other aqueous fluids, such that after dissolution of the spacer <NUM>, a biasing force of the electronic conductor <NUM> can cause the grounding segment <NUM> to come into electronic contact with the anode cup <NUM> (e.g., an upper top surface or a side wall surface thereof) to short out the battery <NUM>. In other examples, the spacer <NUM> may comprise a material capable of being overcome, strained, or displaced, for example, because the spacer <NUM> softens, swells, or otherwise mechanically weakens in response to being exposed to a safety condition, typically, saliva, stomach fluids, or other aqueous fluids. The spacer <NUM> may be mechanically weakened, for example, when an aqueous fluid comes into contact with the battery <NUM> and is absorbed by the spacer <NUM> such that the spacer <NUM> softens, swells and/or forms a gel. As a result of such mechanical weakening of the spacer <NUM>, a biasing force of the electronic conductor <NUM> can cause the grounding segment <NUM> to engage and come into electronic contact with the anode cup <NUM> to thereby short out the battery <NUM>, for example, during a safety condition (or other contact of the battery <NUM> with an aqueous fluid). As discussed above, a safety condition can occur when a person, infant, or pet animal swallows the battery <NUM>, exposing the battery <NUM> to an aqueous solution in the form of saliva or stomach fluid. In the illustrated embodiment, the insulating gasket <NUM> is shown as a separate component from spacer <NUM> such that it can remain intact after the battery <NUM> is contacted with an aqueous fluid and the spacer undergoes a physical change, keeping the cathode <NUM> and anode <NUM> materials inside the battery <NUM>. However, in another embodiment, the insulating gasket <NUM> and spacer <NUM> can be of unitary construction, with the spacer <NUM> functioning as and effectively providing an insulating gasket <NUM> as well. Thus, in this embodiment, a separate insulating gasket <NUM> is not present and the spacer <NUM> comprising an electronically insulating material, in addition to being disposed between the grounding segment <NUM> and the anode cup <NUM>, also extends into the cathode can <NUM> and entirely surrounds the anode cup <NUM> such that the anode cup <NUM> cannot contact the cathode can <NUM>. Of course, batteries with safety mechanisms in which the reverse configuration is used are contemplated as noted above.

As shown in the example illustrated in <FIG>, the electronic conductor <NUM> includes two segments, attaching segment <NUM> and grounding segment <NUM>. Each segment <NUM>, <NUM> is electronically coupled to a first pole of the battery <NUM> (e.g., the cathode can <NUM>) and each segment <NUM>, <NUM> is electronically isolated from a second pole of the battery <NUM> (e.g., the anode cup <NUM>) by the spacer <NUM>. In the illustrated embodiment, the attaching segment <NUM> is electronically coupled to (and indeed in direct physical contact with) the cathode can <NUM>, i.e., the positive battery pole, and the grounding segment <NUM> of the electronic conductor <NUM> is not in electronic contact with but is biased toward engagement with the anode cup <NUM>, i.e., the negative battery pole.

It will be appreciated that either of the positive pole or the negative pole of the battery <NUM> may be electronically connected to the electronic conductor <NUM>, with the other of the two poles being electronically isolated from the tensioned conductor <NUM> under normal use or storage conditions. It will be further appreciated that the spacer <NUM> may therefore be disposed adjacent to either the positive pole or the negative pole of the battery <NUM>, to prevent electronic contact of the electronic conductor <NUM> therewith under normal use or storage conditions. Thus, it is also contemplated that the electronic conductor <NUM> may alternatively be positioned about battery <NUM> such that it is electronically coupled to (e.g., in direct physical contact with) a top surface of the anode cup <NUM> and spaced away from a sidewall of the cathode can <NUM> by a spacer <NUM> disposed between the electronic conductor <NUM> and the cathode can <NUM> during normal use conditions.

Further still, while the attaching segment <NUM> and the grounding segment <NUM> are shown in the illustrated example as being of unitary construction and thus directly connected to one another such that they are continuously electronically coupled to one another, in other examples, the attaching segment <NUM> and the grounding segment <NUM> of a battery safety mechanism (not shown) may be electronically isolated from one another during normal operation of the battery, only to become electronically coupled to one another during a safety condition, such as in response to the presence of an aqueous solution or bodily fluid. Thus, in another example, the attaching segment <NUM> may be in electronic contact with either the positive pole or the negative pole of the battery <NUM> and the grounding segment <NUM> may be in electronic contact with the other of the positive pole and the negative pole of the battery <NUM>, with the spacer <NUM> comprising an insulator material being positioned between the two segments <NUM>, <NUM>, such that the segments <NUM>, <NUM> are not electronically coupled to one another (and thus the positive and negative poles are not electronically coupled to one another) during normal operation of the battery. After encountering a safety condition (or other contact of the battery <NUM> with an aqueous fluid) so as to effect dissolution, softening, and/or swelling of the electronically insulating material of the spacer <NUM>, the grounding segment <NUM> can engage and come into electronic contact with the attaching segment <NUM> to thereby short out the battery <NUM>. As discussed above, a safety condition can occur when a person, infant, or pet animal swallows the battery <NUM>, exposing the battery <NUM> to an aqueous solution in the form of saliva or stomach fluid.

<FIG> illustrates a plot of cell voltage versus time for two different batteries, a conventional button cell battery (in this example, a button cell battery DL2032 available from Duracell Inc. ) and a comparable button cell battery further equipped with a safety mechanism adapted to protect against tissue damage and/or electrolysis according to the disclosure, such as battery <NUM> depicted in <FIG>. After contacting the batteries with a <NUM> KCl solution for about <NUM> seconds, gassing started at the anode cup <NUM>, and the actual cell voltages of the tested batteries dropped, as the batteries began to short. In the conventional battery, the voltage drop stops at around <NUM>. 5V after around <NUM> seconds. 5V voltage, although reduced, is sufficient to cause the electrolysis of water and generation of hydroxide ions. Thus, even though reduced, this voltage can cause burning and damage to esophageal tissues should the battery should become lodged in a human throat. Of course, the battery could also cause significant stomach distress if successfully swallowed. The battery <NUM> with the safety mechanism adapted to protect against tissue damage and/or electrolysis, by contrast, is further shorted such that the electrolysis of water substantially no longer occurs at the anode cup <NUM>. Indeed, in the illustrated example, the safety mechanism further short circuits the battery <NUM> substantially completely to almost 0V. In the example illustrated in <FIG>, a spacer <NUM> comprising an electronically insulating material that is a water-soluble material capable of being dissolved in saliva, stomach fluids, or other aqueous fluid was used. Specifically, the spacer <NUM> of the battery <NUM> with safety mechanism illustrated in <FIG> comprised a benign solid, in this case a benign salt, specifically, NaHPO<NUM> (about <NUM> wt. %), and a water-soluble material, specifically, polyacrylic acid (about <NUM> wt.

In <FIG>, another example battery <NUM>, also illustrated as a button cell battery, includes a cathode can <NUM> and an anode cup <NUM>. A cathode <NUM> is disposed in the cathode can <NUM> and an anode <NUM> is disposed in the anode cup <NUM>. The cathode <NUM> and the anode <NUM> are separated electronically by a separator <NUM> within the battery <NUM>. Each of the cathode can <NUM> and the anode cup <NUM> forms a different pole of the battery <NUM>, with the cathode can <NUM> forming a positive pole and the anode cup <NUM> forming a negative pole. An insulating gasket <NUM> electronically isolates the cathode can <NUM> from the anode cup <NUM>, the insulating gasket <NUM> preventing any part of the anode cup <NUM> from contacting the cathode can <NUM> and sealing the battery <NUM> to prevent electrolyte loss. The battery <NUM> shares many of the same elements shown in connection with battery <NUM> described above in <FIG> and, as such, generally only the differences are discussed herein.

The battery <NUM> further includes a safety mechanism adapted to protect against tissue damage and/or electrolysis comprising a spacer <NUM>, the spacer <NUM> comprising an electronically insulating material that is capable of undergoing a physical change subsequent to exposure to an aqueous solution such as saliva, stomach fluids, water, or other aqueous fluid, and an electronic conductor <NUM> embedded or disposed within the spacer <NUM>. The spacer <NUM> is disposed above the insulating gasket <NUM>, and functions similarly to the insulating gasket <NUM> during normal operation, in that the spacer <NUM> electronically isolates the cathode can <NUM> from the anode cup <NUM>. In the illustrated example, the electronic conductor <NUM> embedded or disposed within the spacer <NUM> makes direct physical contact with and thus is electronically coupled to one of the first and second battery poles, here the anode cup <NUM>, while being electronically separated from the other of the first and second battery poles, here the cathode can <NUM>, by the spacer <NUM>. In this example, the electronic conductor <NUM> is electronically coupled to the anode cup <NUM> at contact location <NUM>. Similar to the electronic coupling between the cathode can <NUM> and the electronic conductor <NUM> illustrated in battery <NUM> shown in <FIG>, the electronic coupling between the electronic conductor <NUM> and the anode cup <NUM> can be a fixed direct physical connection maintained throughout operation of the battery <NUM>, both during normal operation and storage, and subsequent to the battery <NUM> encountering a safety condition. The connection between the electronic conductor <NUM> and anode cup <NUM> at contact location <NUM> can be fixed, for example, by a welding operation or a mechanical connection.

In the illustrated form, the electronic conductor <NUM> extends from the contact location <NUM> into two branching arm segments that traverse a portion of the distance between the anode cup <NUM> and the cathode can <NUM> and are biased towards engagement with the cathode can <NUM>. While in this example, only a single electronic conductor <NUM> is shown, one or more of such electronic conductors <NUM> may be included. After coming into contact with an aqueous solution such as saliva, stomach fluids, water, or other aqueous fluid, dissolution, softening, and/or swelling of the spacer <NUM> occurs, such that the electronic conductor <NUM> is able to deflect into electronic contact with the cathode can <NUM>, thereby electronically coupling the cathode can <NUM> to the anode cup <NUM>. As a result, the battery <NUM> is shorted and the consumer is protected during a safety condition, such as if the battery <NUM> has been swallowed by a person or pet animal. In the illustrated embodiment, the insulating gasket <NUM> is shown as a separate component from spacer <NUM> such that it can remain intact after the battery <NUM> is contacted with an aqueous fluid, keeping the cathode <NUM> and anode <NUM> materials inside the battery <NUM>. However, in another embodiment, the insulating gasket <NUM> and spacer <NUM> can be of unitary construction, with the spacer <NUM> additionally functioning as and effectively providing an insulating gasket <NUM> as noted with the spacer <NUM> and the insulating gasket <NUM> described in connection with <FIG> above.

In this example, the electronic conductor <NUM> may be partially or wholly embedded or disposed within the spacer <NUM>, as long as the resistive force of the spacer <NUM> is greater than or equal to a biasing force of the electronic conductor <NUM> such that the electronic conductor does not deflect into electronic contact with the cathode can <NUM> under normal use conditions. Thus, it should be noted the electronic conductor <NUM> can be biased toward engagement with the cathode can <NUM>, for example, the electronic conductor <NUM> can be biased towards engagement with an inner surface of the cathode can <NUM>. Of course, the opposite configuration in which the electronic conductor <NUM> makes direct physical contact with and thus is electronically coupled to the cathode can <NUM>, while being electronically separated from the anode cup <NUM> by the spacer <NUM> is also contemplated.

<FIG> illustrate an exemplary battery <NUM> with a safety mechanism adapted to protect against tissue damage and/or electrolysis according to the invention. The battery <NUM> includes a cathode can <NUM> and an anode cup <NUM>. A cathode <NUM> is disposed in the cathode can <NUM> and an anode <NUM> is disposed in the anode cup <NUM>. The cathode <NUM> and the anode <NUM> are separated electronically by a separator <NUM> within the battery <NUM>. Each of the cathode can <NUM> and the anode cup <NUM> forms a different pole of the battery <NUM>, with the cathode can <NUM> forming a positive pole and the anode cup <NUM> forming a negative pole. An insulating gasket <NUM> electronically isolates the cathode can <NUM> from the anode cup <NUM>, the insulating gasket <NUM> preventing any part of the anode cup <NUM> from contacting the cathode can <NUM> and sealing the battery <NUM> to prevent electrolyte loss. The battery <NUM> shares many of the same elements shown in connection with battery <NUM> described above in <FIG> and, as such, generally only the differences are discussed herein.

The first battery pole, here the cathode can <NUM>, includes an electronic conductor <NUM> that is integrated into the cathode can <NUM> as a continuation or extension thereof. Thus, whereas the electronic conductor <NUM> is illustrated in <FIG> as a component separate from the cathode can <NUM>, the electronic conductor <NUM> and the cathode can <NUM> are of unitary construction, for example, the electronic conductor <NUM> comprises a continuation or extension of the cathode can <NUM> that can electronically couple to the second battery pole, here an exterior surface of the anode cup <NUM>, in order to short the battery <NUM> subsequent to the battery being exposed to an aqueous solution such as saliva, stomach fluids, water, or other aqueous fluid. The electronic conductor <NUM> may have a protrusion (not shown) that will facilitate electronic contact with the other battery pole an outer wall of the anode cup <NUM> subsequent to the battery <NUM> encountering a safety condition.

In the embodiment illustrated in <FIG>, the electronic conductor <NUM> of the cathode can <NUM> is separated from the anode cup <NUM> by a spacer <NUM> comprising an electronically insulating material. The spacer <NUM> is integrated into a seal region of the battery <NUM>, the spacer <NUM> being disposed between the electronic conductor <NUM> and an outer wall of the anode cup <NUM>, thereby preventing electronic contact between the electronic conductor <NUM> and the anode cup <NUM>. Under normal use conditions, the spacer <NUM> may provide a further seal to the battery <NUM> that also includes a common insulating gasket <NUM> as mentioned above. In concert, the spacer <NUM> and the insulating gasket <NUM> prevent an electronic connection between the anode cup <NUM> and the cathode can <NUM>, such that these two components are electronically isolated from one another under normal use conditions. After the battery <NUM> is exposed to aqueous solutions or bodily fluids and upon dissolution, softening, and/or swelling of the electronically insulating material of the spacer <NUM>, the continuation or extension <NUM> of the cathode can <NUM> can be biased towards engagement with an outer wall of the anode cup <NUM> and can contact and thus become electronically coupled to the anode cup <NUM>. As a result, the battery <NUM> is shorted and the consumer is protected during a safety condition, such as if the battery <NUM> has been swallowed by a person or pet animal. In the illustrated embodiment, the insulating gasket <NUM> is shown as a separate component from spacer <NUM> such that it can remain intact after the battery <NUM> is contacted with an aqueous fluid, keeping the cathode <NUM> and anode <NUM> materials inside the battery <NUM>. However, in another embodiment, the insulating gasket <NUM> and spacer <NUM> can be of unitary construction, with the spacer <NUM> additionally functioning as and effectively providing an insulating gasket <NUM> as noted with the spacer <NUM> and the insulating gasket <NUM> described in connection with <FIG> above.

Typically, the integrated continuation or extension <NUM> of the cathode can <NUM> is formed during a crimping process when the battery <NUM> is manufactured. In the illustrated example, the continuation or extension <NUM> of the cathode can <NUM> is formed as an extending part of a sidewall of the cathode can <NUM>. The continuation or extension <NUM> includes a bend and is biased toward engagement with the anode cup <NUM>. The continuation or extension <NUM> can be pre-cut to form a biased electronic conductor, for example.

<FIG> illustrate an exemplary battery <NUM> with a safety mechanism adapted to protect against tissue damage and/or electrolysis according to the disclosure. The battery <NUM> includes a cathode can <NUM> and an anode cup <NUM>. A cathode <NUM> is disposed in the cathode can <NUM> and an anode <NUM> is disposed in the anode cup <NUM>. The cathode <NUM> and the anode <NUM> are separated electronically by a separator <NUM> within the battery <NUM>. Each of the cathode can <NUM> and the anode cup <NUM> forms a different pole of the battery <NUM>, with the cathode can <NUM> forming a positive pole and the anode cup <NUM> forming a negative pole. An insulating gasket <NUM> electronically isolates the cathode can <NUM> from the anode cup <NUM>, the insulating gasket <NUM> preventing any part of the anode cup <NUM> from contacting the cathode can <NUM> and sealing the battery <NUM> to prevent electrolyte loss. The battery <NUM> shares many of the same elements shown in connection with battery <NUM> described above in <FIG> and, as such, generally only the differences are discussed herein.

Battery <NUM> has features similar to those of batteries <NUM> and <NUM> (illustrated in FIGS. 3A, 3B, <FIG>). As shown in <FIG>, battery <NUM> differs from battery <NUM> in that the safety mechanism includes a second electronic conductor <NUM>, which may be embedded or disposed within spacer <NUM> and may extend around the entire circumference of the anode cup <NUM> or may extend along only a portion of the anode cup <NUM> circumference. The second electronic conductor <NUM> makes direct physical contact with and thus is electronically coupled to the anode cup <NUM>, while being electronically isolated from the first conductor <NUM> and thus the cathode can <NUM> by the spacer <NUM>. After the battery <NUM> is exposed to aqueous solutions or bodily fluids and upon dissolution, softening, and/or swelling of the electronically insulating material of the spacer <NUM>, the continuation or extension <NUM> of the cathode can <NUM> can be biased towards engagement with an outer wall of the anode cup <NUM> and can contact and thus become electronically coupled to the anode cup <NUM>. In addition, after the battery comes into contact with an aqueous solution such as saliva, stomach fluids, water, or other aqueous fluid, such that dissolution, softening, and/or swelling of the spacer <NUM> occurs, the electronic conductor <NUM> is able to deflect into electronic contact with the cathode can <NUM>, thereby electronically coupling the cathode can <NUM> to the anode cup <NUM>. As a result of these interactions, the battery <NUM> is shorted and the consumer is protected during a safety condition, such as if the battery <NUM> has been swallowed by a person or pet animal. In the illustrated embodiment, the insulating gasket <NUM> is shown as a separate component from spacer <NUM> such that it can remain intact after the battery <NUM> is contacted with an aqueous fluid, keeping the cathode <NUM> and anode <NUM> materials inside the battery <NUM>. However, in another embodiment, the insulating gasket <NUM> and spacer <NUM> can be of unitary construction, with the spacer <NUM> additionally functioning as and effectively providing an insulating gasket <NUM> as noted with the spacer <NUM> and the insulating gasket <NUM> described in connection with <FIG> above.

<FIG> illustrates an additional exemplary battery <NUM> with a safety mechanism adapted to protect against tissue damage and/or electrolysis according to the disclosure. The battery <NUM> includes a cathode can <NUM> and an anode cup <NUM>. A cathode <NUM> is disposed in the cathode can <NUM> and an anode <NUM> is disposed in the anode cup <NUM>. The cathode <NUM> and the anode <NUM> are separated electronically by a separator <NUM> within the battery <NUM>. Each of the cathode can <NUM> and the anode cup <NUM> forms a different pole of the battery <NUM>, with the cathode can <NUM> forming a positive pole and the anode cup <NUM> forming a negative pole. An insulating gasket <NUM> electronically isolates the cathode can <NUM> from the anode cup <NUM>, the insulating gasket <NUM> preventing any part of the anode cup <NUM> from contacting the cathode can <NUM> and sealing the battery <NUM> to prevent electrolyte loss. The battery <NUM> shares many of the same elements shown in connection with battery <NUM> described above in <FIG> and, as such, generally only the differences are discussed herein.

As shown in <FIG>, battery <NUM> includes a first electronic conductor <NUM> in electronic contact with a cathode can <NUM> and a second electronic conductor <NUM> in electronic contact with an anode cup <NUM>. A spacer <NUM> is disposed between the first electronic conductor <NUM> and the second electronic conductor <NUM>. After the battery <NUM> is exposed to aqueous solutions or bodily fluids and upon dissolution, softening, and/or swelling of the electronically insulating material of the spacer <NUM>, the second electronic conductor <NUM> can be biased towards engagement with the first electronic conductor such that the second electronic conductor <NUM> can contact the first electronic conductor <NUM> and thus electronically couple the cathode can <NUM> to the anode cup <NUM>. As a result of these interactions, the battery <NUM> is shorted and the consumer is protected during a safety condition, such as if the battery <NUM> has been swallowed by a person or pet animal. In the illustrated embodiment, the cathode can <NUM> and the first electronic conductor are shown as separate components, however, it should be understood that the electronic conductor <NUM> and the cathode can <NUM> may be of unitary construction such that the cathode can <NUM> itself additionally functioning and effectively providing an electronic conductor <NUM>. Thus, in this embodiment, a separate electronic conductor <NUM> is not needed.

illustrates an additional exemplary battery <NUM> with a safety mechanism adapted to protect against tissue damage and/or electrolysis according to the disclosure. The battery <NUM> includes a cathode can <NUM> and an anode cup <NUM>. A cathode <NUM> is disposed in the cathode can <NUM> and an anode <NUM> is disposed in the anode cup <NUM>. The cathode <NUM> and the anode <NUM> are separated electronically by a separator <NUM> within the battery <NUM>. Each of the cathode can <NUM> and the anode cup <NUM> forms a different pole of the battery <NUM>, with the cathode can <NUM> forming a positive pole and the anode cup <NUM> forming a negative pole. An insulating gasket <NUM> electronically isolates the cathode can <NUM> from the anode cup <NUM>, the insulating gasket <NUM> preventing any part of the anode cup <NUM> from contacting the cathode can <NUM> and sealing the battery <NUM> to prevent electrolyte loss. The battery <NUM> shares many of the same elements shown in connection with battery <NUM> described above in <FIG> and, as such, generally only the differences are discussed herein.

As shown in <FIG>, battery <NUM> includes a first spacer <NUM> and a second spacer <NUM>'. The spacer <NUM> may comprise discrete sections or a continuous circumferential layer about the cathode can <NUM>. Similarly, the spacer <NUM>' may comprise a continuous layer or discrete sections. The spacers <NUM> and <NUM>' are disposed between the cathode can <NUM> and the anode cup <NUM> (corresponding to first and second battery poles) and the electronic conductor <NUM>. After the battery <NUM> is exposed to aqueous solutions or bodily fluids and upon dissolution, softening, and/or swelling of the electronically insulating material of the spacers <NUM> and <NUM>', the electronic conductor <NUM> can be biased towards engagement with the cathode can <NUM> and the anode cup <NUM>, thus electronically coupling the cathode can <NUM> and the anode cup <NUM>. As a result of these interactions, the battery <NUM> is shorted and the consumer is protected during a safety condition, such as if the battery <NUM> has been swallowed by a person or pet animal.

Throughout this specification, plural instances may implement components or structures described as a single instance.

Some embodiments described herein use the terms "coupled" and/or "connected". For example, some embodiments are described using the term "coupled" or "connected" to describe two or more elements that are shown in direct physical or electronic contact. The terms "coupled" and "connected," however, may also mean that two or more elements are not in direct physical contact with each other, but still cooperate or interact with each other.

For example, an element A or B is satisfied by any one of the following: A is present and B is not present, A is not present and B is present, and both A and B are present.

In addition, use of the "a" or "an" are employed to describe elements and components of the embodiments herein. This is done merely for convenience and to give a general sense of the description. This description, and the claims that follow, should be read to include one or at least one and the singular also includes the plural unless it is obvious that it is meant otherwise.

Claim 1:
A battery (<NUM>) with a safety mechanism adapted to protect against tissue damage and/or electrolysis comprising:
a housing comprising a cathode can (<NUM>) and an anode cup (<NUM>), and a spacer (<NUM>) comprising an electronically insulating material, wherein the spacer (<NUM>) is provided between an extension (<NUM>) of the cathode can (<NUM>) and an outer wall of the anode cup (<NUM>) such that electronic contact between the cathode can (<NUM>) and the anode cup (<NUM>) is prevented, the spacer (<NUM>) being capable of undergoing a physical change in the presence of an aqueous solution such that the spacer (<NUM>) can dissolve, soften, or swell, a resistive force of the spacer (<NUM>) is reduced to less than a biasing force of the extension (<NUM>), and electronic coupling between the extension (<NUM>) and the anode cup (<NUM>) can occur wherein:
subsequent to the physical change, electronic coupling occurs based on (i) direct physical contact between the extension (<NUM>) and the anode cup (<NUM>) or (ii) indirect physical contact between the extension (<NUM>) and the anode cup (<NUM>) via one or more additional intervening electronically conducting materials disposed between the extension (<NUM>) and the anode cup (<NUM>),
wherein the extension (<NUM>) and the cathode can (<NUM>) are of unitary construction, and the extension (<NUM>) is biased towards engagement with an outer wall of the anode cup (<NUM>).