Patent Description:
A common mechanism for providing battery power to portable electronic devices is by use of modular secondary battery packs. Such battery packs often employ rechargeable lithium-ion based battery cells, such as lithium-ion polymer battery cells, also known as Li-Poly, Li-Pol, or LiPo cells.

A protection circuit module (PCM) is usually included in the battery pack, being connected to the battery cell by a pair of electrodes to perform protective functions with respect to operation of the battery cell. Typical functions of the PCM include preventing overcharge, preventing over discharge, and preventing over-current of the battery cell.

In many electronic devices, including mobile devices such as mobile phones and wearable devices such as smart glasses, space is at a premium, demanding increasing space-saving in battery pack design. Space-saving in battery packs can, however, come at a cost when the available space/volume for PCM component are reduced to suboptimal levels.

Battery pack arrangements with included PCMs are described in <CIT>, <CIT>, and <CIT>.

The invention is a battery pack and method as defined in the appended claims.

Various ones of the appended drawings merely illustrate example embodiments of the present disclosure and cannot be considered as limiting its scope. To facilitate collation of numbered items in the description to the drawings, the first digit of each numbered item corresponds to the figure in which that item first appears. In the drawings:.

The headings provided herein are merely for convenience and do not necessarily affect the scope or meaning of the terms used.

<FIG> show an example of an existing battery pack structure. The conventional battery pack <NUM> of <FIG> includes a single lithium polymer battery cell <NUM> coupled to a safety circuit in the form of a protection circuit module (PCM) <NUM>. As mentioned previously, the PCM <NUM> provides power control functionality to the battery cell <NUM>, e.g. for safety purposes. Typically, the PCM prevents overcharge, over-discharge, and/or overcurrent in the battery cell <NUM>. The PCM <NUM> is connected to the battery cell <NUM> by a pair of electrodes <NUM> that project from the battery cell <NUM>. In conventional fashion, the pair of electrodes <NUM> are terminals of the battery cell <NUM>, consisting of a cathode and an anode.

The PCM <NUM> comprises a printed circuit board or protection circuit board (PCB) <NUM> and a plurality of PCM components mounted on the PCB <NUM>, the available volume for location of PCM components on the PCB <NUM> being indicated in the drawings by PCM block <NUM>. It will be appreciated that the PCB <NUM> comprises a rectangular substrate carrying an integrated protection circuit thereon for connection to the PCM components and to the battery electrodes <NUM>. To facilitate modular use of the battery pack <NUM>, the assembly consisting of the battery cell <NUM> and the PCM <NUM> is housed in a casing <NUM>, part of which provides insulation <NUM> covering or the PCM <NUM>. For clarity of view, the insulation <NUM> and its analogs are omitted from some of the schematic views with respect to a number of illustrated example embodiments.

Having a relatively thin, elongate rectangular shape, the PCB <NUM> has a pair of substantially rectangular major outer faces which are substantially parallel to one another and which face in opposite outward directions. In <FIG>, these opposite major faces are designated as a top face <NUM> and a bottom face <NUM>. Note that in this description, reference to the top and bottom faces do not indicate a particular orientation or spatial attribute of the respective faces, but is instead used as arbitrary designations to distinguish between these two faces in description.

The top and bottom faces <NUM>, <NUM> are connected by a peripheral edge face that extends transversely between them. The edge face includes a pair of end edge faces at the longitudinal end edges of the PCB <NUM>, and a pair of side edge faces <NUM>, <NUM> (<FIG>) at the lateral side edges of the PCB <NUM>. For clarity, the side edge faces (best seen in <FIG>) are designated as a front edge face <NUM> furthest from the battery cell <NUM>, and a rear edge face <NUM> closest to the battery cell <NUM>. The PCB <NUM> is oriented such that a widthwise dimension of the PCB <NUM> (i.e., the dimension extending between the side edge faces <NUM>, <NUM>) is substantially parallel to a lengthwise direction of the battery cell <NUM>. A lengthwise direction of the PCB <NUM> (i.e., the dimension of the PCB <NUM> that extends between its end edges) is oriented transversely to the lengthwise direction of the battery cell <NUM>. The thickness dimension of the PCB <NUM> (i.e., that dimension of the PCB <NUM> that extends between the top face <NUM> and the bottom face <NUM>), being normal to the widthwise dimension, is oriented transversely to the lengthwise direction of the battery cell <NUM>.

As seen in <FIG>, connections of the respective electrodes <NUM> to the PCB <NUM> are in the existing battery back <NUM> located on the top face <NUM> of the PCB <NUM>. Each electrode comprises a metal tab <NUM> that projects longitudinally (relatively to the lengthwise direction of the battery cell <NUM>) from the battery cell <NUM>, passes beneath the bottom face <NUM> of the PCB <NUM>, and is bent <NUM>° to fold over into contact with the top face <NUM> at respective terminal end portions <NUM>. The electrodes <NUM> are typically soldered to respective terminal pads provided on the PCB <NUM>.

Location of the electrode contacts on the top face <NUM> interrupts the available space for the PCM block <NUM>, so that the cumulative available volume for PCM components on the PCB top face <NUM> is given by the sum of three separate PCM sub-blocks, indicated as 118a, 118b, and 118c.

The description that follows includes devices, systems, methods, techniques, instruction sequences, and computing machine program products that embody illustrative embodiments of the disclosure. In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide an understanding of various embodiments of the disclosed subject matter. It will be evident, however, to those skilled in the art, that embodiments of the disclosed subject matter may be practiced without these specific details.

One aspect of the disclosure provides for a battery pack comprising two batteries sharing a single PCM. This provides an overall more compact protection circuit packaging, allowing additional system volume to be allocated to additional battery capacity or allows for a smaller, slimmer design by freeing up space for the same battery capacity.

The electrodes of the pair of battery cells of the battery pack may all be connected to a single, common PCB of the PCM. In some embodiments, the batteries are elongate and are longitudinally aligned with a spacing between adjacent ends of the batteries, the common PCM being located in the spacing between the batteries. The PCB is in some embodiments oriented "vertically" between the two batteries, by which is meant that the thickness dimension of the PCB (i.e., that dimension of the PCB which extends between its major outer faces) extends in the lengthwise direction of the batteries. Worded differently, the widthwise dimension of the PCB stands upright between the batteries, when the battery pack is seen in side view.

In some such embodiments, the respective pairs of electrodes may be connected to opposite major faces of the PCB, so that each of the major outer faces of the PCB is interrupted by a respective pair of electrode connections. In other embodiments, all four electrodes are connected to a single one of the pair of major faces, so that the other one of the major faces is uninterrupted by any electrode connection and is substantially entirely available for the placement of PCM components thereon.

In yet further embodiments, the electrodes of at least one of the batteries may be connected to the edge face of the PCB, so that both of the major faces are uninterrupted by any electrode connection and are substantially wholly available for receiving PCM components thereon. In a particular example embodiment, the PCB has an upright orientation (as described previously), with the electrodes of the respective batteries being connected to opposite side edge faces of the PCB.

A number of specific example embodiments will now be described in greater detail with reference to the <FIG>. For ease of understanding, the same reference numerals are used for indicating corresponding parts or elements in <FIG> and in <FIG>, even when there are in some instances differences between the specifics of the corresponding parts or elements.

<FIG> shows one example embodiment of a dual-cell battery pack <NUM> with a nested PCM arrangement. The battery pack <NUM> includes a pair of lithium polymer battery cells <NUM>, <NUM>' identical to that described with reference to <FIG>. Note that, in this description, the term battery refers to a battery cell together with its electrodes. As can best be seen in <FIG>, the battery cells <NUM>, <NUM>' are longitudinally aligned, in that their lengthwise dimensions are parallel and in line with one another, the battery cells <NUM>, <NUM>' lying substantially in a common plane. The battery cells <NUM>, <NUM>' are arranged end-to-end, with a longitudinal spacing between the adjacent ends of the batteries <NUM>, <NUM>'. Returning to <FIG>, it can be seen that a common, shared PCM <NUM> is located within the longitudinal spacing between the battery cell <NUM>, with respective electrodes <NUM>, <NUM>' being connected to a single PCB <NUM> forming part of the common PCM <NUM>.

The PCB <NUM> has an "upright," orientation in which the widthwise direction of the PCB <NUM> (i.e., that dimension of the PCB <NUM> that extends between its opposite lateral side edges) is normal to the lengthwise direction of the aligned battery cells <NUM>, <NUM>'. In other words, the thickness dimension of the PCB <NUM> (i.e., that dimension of the PCB <NUM> that extends between the opposite major outer faces <NUM>, <NUM>) extends in the lengthwise direction of the aligned battery cells <NUM>, <NUM>'. In the example embodiment of <FIG>, the electrode <NUM> of a first one of the battery cells <NUM> is connected to the bottom face <NUM> of the PCB <NUM>, while the electrode <NUM>' of a second one of the battery cells <NUM>' is connected to the top face <NUM> of the PCB <NUM>.

Terminal end portions <NUM>, <NUM>' of the respective electrodes <NUM>, <NUM>' are soldered or welded to the corresponding exposed gold contact pads <NUM>, <NUM>' are provided on the opposite major faces <NUM>, <NUM> of the PCB <NUM>. As can be seen in <FIG>, the terminal end portion <NUM>, <NUM>' of each battery cell <NUM>, <NUM>' is connected to the major face of the PCB <NUM> furthest therefrom. The battery cells <NUM>, <NUM>' are inverted, so that their respective electrodes <NUM>, <NUM>' are transversely misaligned relative to the longitudinal direction of the battery pack <NUM>. Thus, the electrode tab <NUM> of the electrode <NUM> of the first battery cell <NUM> projects longitudinally from the battery cell <NUM>, extends past a respective side edge of the PCB <NUM>, and thereafter bends substantially <NUM>° such that its terminal end portion <NUM> lies flat against the corresponding contact pad <NUM>' provided on the bottom face <NUM> of the PCB <NUM>. Each electrode <NUM>' of the second battery cell <NUM>' is similarly arranged, except that its electrode tab <NUM>' extends past the opposite side edge of the PCB <NUM>, and its terminal end portion <NUM>' is soldered or welded to the contact pad <NUM> of the opposite major face <NUM> of the PCB <NUM>.

Electronic PCM components <NUM> are mounted on both of the major faces <NUM>, <NUM> of the PCB <NUM>. As can best be seen in <FIG>, the available space for the PCM components <NUM> is on both major faces <NUM>, <NUM> interrupted by the respective electrodes <NUM>, <NUM>', so that the PCM block is on both faces separated into three sub-blocks, similar to the arrangement of the <FIG>. In this example embodiment, the PCM <NUM> provides a single protection circuit to which both battery cells <NUM>, <NUM>' are connected by their respective electrodes <NUM>, <NUM>', so that the PCM components <NUM> on the opposite faces <NUM>, <NUM> of the PCB <NUM> form part of a single, common, protection circuit. In other embodiments, the PCB <NUM> and PCM components <NUM> may be configured to provide separate protection circuits to separately control operation of the respective battery cells <NUM>, <NUM>'.

It is a benefit of the nested PCM arrangement of the battery pack <NUM> that it provides for space saving by reducing the length of the battery pack <NUM> without compromising either battery capacity or available space for PCM components <NUM>. <FIG> shows a comparison of, on the one hand, two of the earlier-described conventional battery packs <NUM>, <NUM>' arranged in an end to end configuration, and, on the other hand, the battery pack <NUM> with a common PCM in a nested configuration. Note that the respective battery cells <NUM>, <NUM>' of both of the illustrative configurations are identical, yet the overall length of the nested battery pack <NUM> is smaller than that of the conventional stack, as represented by the length difference Δx. Not only does the PCM sharing of the battery back <NUM> thus provide for space saving, but a larger volume for PCM mounting on the PCB <NUM> is provided by utilizing both major faces <NUM>, <NUM> of the PCB <NUM>. Note that, in other embodiments, the space saving achieved by the described PCM nesting can be utilized to increase battery length, and thus battery capacity, without increasing the dimensional parameters of the battery stack.

<FIG> shows another example embodiment of a dual cell battery pack <NUM> with a shared PCM arrangement. The battery pack <NUM> is largely similar in arrangement and configuration to the battery pack <NUM> described with reference to <FIG>, a major distinction being that the electrodes <NUM>, <NUM>' of both battery cells <NUM>, <NUM>' are connected to a single, common one of the major outer faces <NUM>, <NUM> of the PCB <NUM>. In this example embodiment, all of the electrodes <NUM>, <NUM>' are connected to the bottom face <NUM>.

In this example embodiment, the electrodes are connected to the bottom face <NUM> in a stacked arrangement, so that the electrodes <NUM> of only one of the battery cells <NUM>, <NUM>' are connected directly to the PCB <NUM>, the electrodes <NUM>' of the other battery cell being connected to the underlying electrodes <NUM>. As can be seen in <FIG>, the terminal end portions <NUM> of the electrodes <NUM> of the first battery cell <NUM> is in this example embodiment directly soldered or welded to respective exposed gold contact pads <NUM> on the bottom face <NUM>, the end portions <NUM> of the electrode tabs <NUM> lying flat against the bottom face <NUM>. The electrodes <NUM>' of the second the battery cell <NUM>' is connected to the electrodes <NUM> of the first battery cell <NUM>. In particular, the terminal end portions <NUM>' of the electrode tabs <NUM>' of the second battery cell <NUM>' lie flat against the end portions <NUM> of the first battery cell <NUM>, being soldered or welded thereto to provide a conductive coupling of the second battery cell's electrodes <NUM>' to the protection circuit of the PCM <NUM>.

Note that it is an advantage of the PCM arrangement of the battery pack <NUM> that the top face <NUM> of the PCB <NUM> is uninterrupted by any electrode connections, and is available in its entirety for the placement of PCM components <NUM> thereon. Thus, the battery pack <NUM> has a greater PCM block volume than the battery pack <NUM> described with reference to <FIG>. This may be leveraged in design of PCM component placement to achieve further reduction in the overall length of the battery pack <NUM>, e.g., by reducing the height by which the PCM block projects outwardly from the major faces <NUM>, <NUM>.

<FIG> shows yet a further example embodiment of a dual-cell battery pack <NUM> with a shared PCM <NUM>. The battery pack <NUM> is generally similar in configuration and arrangement to the example embodiment described with reference to <FIG>, a major distinction being that in the example embodiment of <FIG>, electrodes <NUM>, <NUM>' of respective battery cells <NUM>, <NUM>' are connected to the edge face of the PCB <NUM>. In particular, the respective battery cells <NUM>, <NUM>' are connected to different respective side edge faces <NUM>, <NUM>, with the PCB <NUM> having an "upright" orientation in which the opposite major faces <NUM>, <NUM> of the PCB <NUM> face towards the respective battery cells <NUM>, <NUM>' between which the PCM <NUM> is sandwiched.

As can be seen in <FIG>, the electrodes <NUM> of the first battery cell <NUM> is connected to a first one of the side edge faces <NUM>, with the electrodes <NUM>' of the second battery cell <NUM>' being connected to the opposite side edge face <NUM>. Turning briefly to <FIG> (which shows the PCM <NUM> during an intermediate stage of manufacture, as will be described later herein) it can be seen that each electrode <NUM> includes an elongated connective portion in the form of an electrode tab <NUM> of similar width to that described in the previous embodiments, and a widened terminal end portion <NUM>. Note again that, as can be seen in <FIG>, the peripherally extending edge face of the PCB <NUM> consists of a pair of opposite side edge faces <NUM>, <NUM> (only one of which can be seen in <FIG>) and, transverse thereto, a pair of opposite end edge faces <NUM> (only one of which can be seen in <FIG>).

The end portion <NUM> of each electrode <NUM> is connected by soldering or welding to a respective somewhat wider edge-mounted contact pad <NUM>. In this example embodiment, the contact pads <NUM> are provided by metal surfaces (in this embodiment, gold-plated surfaces) on the respective side edge faces <NUM>, <NUM>, connection of the electrodes <NUM> thereto being achieved by solder joint attachment of the terminal end portions <NUM> to the respective contact pads <NUM>. In other embodiments, the electrodes <NUM> can be welded to the exposed gold pads <NUM>. The contact pads <NUM> are conductively coupled to the integrated circuit of the PCB <NUM>. In this example embodiment, the increased width of the terminal end portions <NUM> and contact pads <NUM> are selected such that the contact surface between the terminal end portions <NUM> and the contact pads <NUM> are at least as great as the corresponding contact surface between the conventionally structured electrodes <NUM> and the PCB <NUM> of existing battery packs, such as the battery pack <NUM> described with reference to <FIG>.

Returning now to <FIG>, it can be seen that the electrode tabs <NUM>, <NUM>' are folded. Each electrode tab <NUM>, <NUM>' thus projects longitudinally from the corresponding battery cell <NUM>, extending past the corresponding side edge face <NUM>, <NUM> of the PCB <NUM>, whereafter it folds back on itself by about <NUM>° towards its soldered connection to the corresponding edge-mounted contact pad <NUM>.

Due to edge-mounting of the electrode connections, both major faces <NUM>, <NUM> of the battery pack <NUM> are substantially free of intrusion by any of the electrodes <NUM>, and are substantially wholly available for the placement of PCM components <NUM>. As discussed previously, the additional free area on the flat major faces <NUM>, <NUM> can be optimized for allowing a more compact PCM <NUM>, while achieving the previously discussed space-saving benefits arising from using a shared PCB <NUM> for the staggered battery cells <NUM>, <NUM>'. Instead, or in addition, the additional volume available for PCM components can be utilized to provide improved PCM functionality and/or reliability.

<FIG> are respective views of an intermediate step in the manufacturing of the respectively described dual cell battery packs. In each of the described embodiments, the respective electrodes <NUM>, <NUM>' are fixedly attached to the PCB <NUM> while the electrodes <NUM>, <NUM>' are in an unbent or pre-final condition, after which the PCB <NUM> is rotated into its final orientation, in the process bending or folding the electrodes <NUM>, <NUM>' into their final positions shown in <FIG>, <FIG> respectively. These different embodiments will now briefly be described separately.

<FIG> shows an intermediate step in the manufacturing of the battery pack <NUM> described and exemplified with reference to <FIG>. In a first step, PCM components <NUM> are connected to both major faces <NUM>, <NUM> of the PCB <NUM> such as to leave access to the respective contact pads <NUM>, <NUM>' (<FIG>) on the opposite major faces. Thereafter, while the respective electrode tabs <NUM>, <NUM>' are in a rectilinear, unbent condition, the respective terminal end portions <NUM>, <NUM>' are soldered to the contact pads <NUM>, <NUM>' on the respective major faces <NUM>, <NUM>. Because the electrode tabs <NUM>, <NUM>' project longitudinally from the battery cells <NUM>, <NUM>', the PCB <NUM> is oriented in a "horizontal" position during attachment, the widthwise dimension of the PCB <NUM> being longitudinally aligned with the battery cells <NUM>, <NUM>'. After such connection, the battery pack <NUM> is in the condition shown in <FIG>.

Thereafter, the PCB <NUM> is rotated through <NUM>° (being rotated counterclockwise in the orientation seen in <FIG>) into the position shown in <FIG>, in which the widthwise dimension of the PCB <NUM> is substantially normal to the lengthwise direction of the aligned batteries cells <NUM>, <NUM>'. Such rotation of the PCM <NUM> is in this embodiment achieved by folding the respective electrode tabs <NUM>, <NUM>' through about <NUM>° to create the respective bends or kinks therein, as shown in <FIG>. Finally, PCM insulation <NUM> is attached on opposite sides of the assembly, covering the longitudinal gap between the battery cells <NUM>, <NUM>' within which the PCM <NUM> is located.

It will be appreciated that a benefit of the described method of manufacturing is that access to the PCB <NUM> and the electrode end portions <NUM>, <NUM>' is easier in the position shown in <FIG> than in the final position of <FIG>. This is in part due to the fact that the longitudinal spacing between the adjacent ends of the battery cells <NUM>, <NUM>' decreases when the PCB <NUM> and the attached electrode end portions <NUM>, <NUM>' are rotated into their final positions. The exemplified method of manufacturing thus promotes manufacturing quality and requires less expensive tooling than would be the case if the electrodes <NUM>, <NUM>' were to be attached to the PCB <NUM> in their final shapes and positions.

<FIG> is analogous to <FIG>, in that it shows an intermediate step in the manufacturing of the battery pack <NUM> described and exemplified with reference to <FIG>. The above description with reference to <FIG> applies analogously to the steps for manufacturing the battery pack <NUM> consistent with <FIG>. A major distinction, however, is that the respective end portions <NUM>, <NUM>' of the electrodes <NUM>, <NUM>' are connected in common to a single one of the major faces of the PCB <NUM>, in this description indicated as the bottom face <NUM>.

Thus, with the PCB <NUM> in the orientation shown in <FIG>, in which its width is aligned with the lengthwise directions of the electrode tabs <NUM>, <NUM>', the end portions <NUM> of the electrode tabs <NUM> of the first battery <NUM> are soldered to respective contact pads <NUM> on the bottom face <NUM> of the PCB <NUM>. Thereafter, the end portions <NUM>' of the electrode tabs <NUM>' of the second battery <NUM>' are soldered to the end portions <NUM> of the first battery <NUM>. The remainder of the manufacturing method proceeds as previously, with the PCM <NUM> being rotated counterclockwise through about <NUM>° into the final position shown in <FIG>, in the process bending or folding the respective electrode tabs <NUM>, <NUM>' through about <NUM>°.

Finally, <FIG> illustrate an intermediate step in the manufacturing of the battery pack <NUM> such as that described previously with reference to <FIG>. Again, the manufacturing process is analogous to that described previously with reference to <FIG>.

In the manufacturing of the battery pack <NUM>, however, the respective end portions <NUM> of the electrode tabs <NUM>, <NUM>' are soldered to the edge-mounted contact pads <NUM> while the electrode tabs <NUM>, <NUM>' are rectilinear and extend in the directions indicated by dotted lines <NUM> in <FIG>. In this position, it will be appreciated that the PCB <NUM> is oriented relative to the battery cells <NUM>, <NUM>' such that its widthwise dimension is transverse to the lengthwise direction of the battery cells <NUM>, <NUM>'.

Thereafter, the PCM <NUM> is rotated through <NUM>° into its final position shown in <FIG>. This is achieved by folding the ends of the electrode tabs <NUM>, <NUM>' back on itself so that the electrode end portion <NUM>, <NUM>' point back towards the battery cell <NUM> from which it projects. To achieve this <NUM>° fold in the electrode tabs <NUM>, <NUM>', the electrode tabs are in this example given two separate closely spaced <NUM>° folds or angles. It will be appreciated that thus bending the electrode tabs <NUM>, <NUM>' draws the battery cells <NUM>, <NUM>' closer together, and rotates the PCM blocks <NUM> into their final positions shown in <FIG>.

<FIG> shows a schematic three-dimensional view of the end portions <NUM> of the electrodes <NUM> of the first battery cell <NUM><NUM> welded to their corresponding edge-mounted contact pads <NUM>, before folding of the electrode tabs <NUM> commences.

From the above-described example embodiments, it will be seen that one aspect of the disclosure provides for a battery pack comprising:.

In some embodiments, the batteries are elongate modular units that are longitudinally aligned with a longitudinal spacing between adjacent ends of the batteries, the PCM being located within the longitudinal spacing between the batteries. The PCB in some such embodiments has a pair of parallel major faces and a peripheral edge face extending transversely between the major faces, a thickness dimension of the PCB being defined by a transverse spacing between the parallel major faces. The PCB may be oriented such that the thickness dimension of the PCB extends in the lengthwise direction of the aligned batteries, each of the major faces of the PCB facing toward a respective one of the batteries between which the PCM is located. In some embodiments, the PCM components are mounted on both major faces of the PCB.

In some embodiments, the electrodes of a first one of the pair of batteries is connected to a first one of the major faces of the PCB, the electrodes of the second one of the pair of batteries being connected to a second, opposite one of the major faces of the PCB. In one such embodiment, for each of the pair of batteries, the electrodes of the battery is connected to the major face of the PCB that is furthest from the battery, facing away therefrom. The respective pairs of electrodes may extend from the respective batteries past opposite side edges of the PCB, the side edges of the PCB extending transversely to the lengthwise direction of the aligned batteries.

In other embodiments, connection of the electrodes to the PCB is such that a first one of the pair of major faces of the PCB is free of electrode connections, such that substantially the entirety of the first major face of the PCB is available for the placement of PCM components. Both pairs of electrodes may for example be connected to a second one of the pair of major faces, opposite to the first major face. In one such embodiment, the pairs of electrodes are connected to the PCB in a stacked configuration in which respective end portions of a first pair of electrodes lie flat against the second major face, and respective end portions of a second pair of electrodes lie flat against the corresponding end portions of the first pair of electrodes.

In yet further embodiments, at least one of the pairs of electrodes is connected to the edge face of the PCB. In some embodiments, both of the pairs of electrodes are connected to the edge face of the PCB. The edge face of the PCB includes a pair of side edge faces extending longitudinally along the PCB on opposite sides thereof, the side edge faces extending transversely relative to the lengthwise direction of the aligned batteries. In some embodiments, the respective pairs of electrodes are connected to opposite side edge faces, such that the electrodes of one battery are connected to one of the side edge faces, and the electrodes of the other battery are connected to the other side edge face.

The PCB made some such embodiments include a respective electrode contact pad on the edge face for connection to a respective electrode, each electrode contact pad having a width greater than a connective portion of a corresponding electrode tab extending between the battery and the electrode contact pad. Each of the electrode contact pads on the edge face may comprise a metal surface deposited on the edge face and connected to a protection circuit integrated in the PCB.

A further aspect of the disclosure provides for a method comprising, for each of a pair of physically separate electrochemical batteries, connecting a respective pair of electrodes of the battery to a protective circuit board (PCB) of a protection circuit module (PCM) that is configured to control one or more functions of the batteries, such that both of the batteries are connected to the single PCB in common. In some embodiments, the PCB has a pair of parallel major faces and a peripheral edge face extending transversely between the major faces, a thickness dimension of the PCB being defined by a transverse spacing between the parallel major faces. The method may in such cases further comprise:.

The connecting of the electrodes to the PCB in some embodiments comprises: connecting the electrodes of a first one of the pair of batteries to a first one of the major faces of the PCB; and connecting the electrodes of a second one of the pair of batteries to a second one of the major faces of the PCB.

In other embodiments, the connecting of electrodes to the PCB comprises: connecting the electrodes of a first one of the pair of battery to a first one major face of the PCB; and connecting the electrodes of a second one of the pair of batteries to the first major face of the PCB.

From the preceding description it will be seen that a number of example embodiments and combinations of example embodiments are disclosed. The disclosed embodiments include, but are not limited to, the enumerated list of example embodiments set out below.

Example <NUM>: A battery pack comprising:.

Example <NUM>: The battery pack of example <NUM>, wherein the pair of batteries are elongate modular units that are longitudinally aligned, with a longitudinal spacing between adjacent ends of the batteries, the PCM being located within the longitudinal spacing between the batteries.

Example <NUM>: The battery pack of example <NUM>, wherein:.

Example <NUM>: The battery pack of example <NUM>, wherein the PCM includes PCM components mounted on both major faces of the PCB.

Example <NUM>: The battery pack of example <NUM> or example <NUM>, wherein the electrodes of a first one of the pair of batteries are connected to a first one of the major faces of the PCB, the electrodes of the second one of the pair of batteries being connected to a second, opposite one of the major faces of the PCB.

Example <NUM>: The battery pack of example <NUM>, wherein, for each of the pair of batteries, the electrodes of the battery are connected to the major face of the PCB that is furthest from that battery, facing away therefrom.

Example <NUM>: The battery pack of example <NUM>, the respective pairs of electrodes extend from the respective batteries past opposite side edges of the PCB, the side edges of the PCB extending transversely to the lengthwise direction of the aligned batteries.

Example <NUM>: The battery pack of example <NUM> or example <NUM>, wherein connection of the electrodes to the PCB is such that a first one of the pair of major faces of the PCB is free of electrode connections, such that substantially the entirety of the first major face of the PCB is available for the placement of PCM components.

Example <NUM>: The battery pack of example <NUM>, wherein both pairs of electrodes are connected to a second one of the pair of major faces, opposite to the first major face.

Example <NUM>: The battery pack of example <NUM>, where in the pairs of electrodes are connected to the PCB in a stacked configuration in which respective end portions of a first pair of electrodes lie flat against the second major face, and respective end portions of a second pair of electrodes lie flat against the corresponding end portions of the first pair of electrodes.

Example <NUM>: The battery pack of example <NUM>, wherein at least one of the pairs of electrodes is connected to the edge face of the PCB.

Example <NUM>: The battery pack of example <NUM>, wherein both of the pairs of electrodes are connected to the edge face of the PCB.

Example <NUM>: The battery pack of example <NUM> or example <NUM>, wherein the PCB includes a respective electrode contact pad on the edge face for connection to a respective electrode, each electrode contact pad having a width greater than a connective portion of a corresponding electrode tab extending between the battery and the electrode contact pad.

Example <NUM>: The battery pack of example <NUM>, wherein each of the electrode contact pads on the edge face comprises a metal surface deposited on the edge face and connected to a protection circuit integrated in the PCB.

Example <NUM>: The battery pack of example <NUM> or example <NUM>, wherein each electrode comprises an electrode tab projecting from the corresponding battery, and a widened end portion connected to the corresponding electrode contact pad by a soldered or a welded connection.

Example <NUM>: A method comprising:
for each of a pair of physically separate electrochemical batteries, connecting a respective pair of electrodes of the battery to a protective circuit board (PCB) of a protection circuit module (PCM) that is configured to control one or more functions of the batteries, such that both of the batteries are connected to the single PCB in common.

Example <NUM>: The method of example <NUM>, wherein:.

Example <NUM>: The method of example <NUM>, wherein the connecting the electrodes to the PCB comprises:.

Example <NUM>: The method of example <NUM>, further comprising operations to form a battery pack according to any one of examples <NUM>-<NUM>.

Although individual operations of one or more methods are illustrated and described as separate operations, one or more of the individu al operations may be performed concurrently, and nothing requires that the operations be performed in the order illustrated.

Although an overview of the disclosed matter has been described with reference to specific example embodiments, various modifications and changes may be made to these embodiments without departing from the broader scope of embodiments of the present disclosure. Such embodiments of the inventive subject matter may be referred to herein, individually or collectively, by the term "invention" merely for convenience and without intending to voluntarily limit the scope of this application to any single disclosure or inventive concept if more than one is, in fact, disclosed.

Claim 1:
A battery pack comprising:
a pair of physically separate electrochemical batteries (<NUM>, <NUM>'), each battery being an elongate modular unit having a respective pair of electrodes (<NUM>, <NUM>') projecting therefrom, each battery being elongate in a lengthwise direction; and
a protection circuit module, PCM, (<NUM>) that is electrically coupled to both of the pair of batteries (<NUM>, <NUM>') and that is configured to control one or more functions of the batteries, the PCM (<NUM>) comprising:
a protective circuit board, PCB (<NUM>), electric coupling of the pair of batteries (<NUM>, <NUM>') to the PCM (<NUM>) being via connection of the respective electrodes (<NUM>, <NUM>') of both of the pair of batteries to the PCB; and
electronic PCM components (<NUM>) mounted on the PCB (<NUM>),
wherein the respective lengthwise dimensions of the pair of batteries (<NUM>, <NUM>') are parallel and in line with one another, the batteries lying substantially in a common plane, with a longitudinal spacing between adjacent ends of the batteries, the PCM (<NUM>) being located within the longitudinal spacing between the batteries (<NUM>, <NUM>');
wherein the PCB (<NUM>) has a pair of parallel major faces (<NUM>, <NUM>) and a thickness dimension, the thickness dimension being defined by a transverse spacing between the parallel major faces (<NUM>, <NUM>);
wherein the electronic PCM components (<NUM>) are mounted on both of the parallel major faces (<NUM>, <NUM>); and
wherein the PCB (<NUM>) is oriented such that the thickness dimension of the PCB (<NUM>) extends in the lengthwise direction of the aligned batteries and each of the major faces (<NUM>, <NUM>) of the PCB (<NUM>) faces toward a respective one of the batteries (<NUM>, <NUM>') between which the PCM (<NUM>) is located.