1. Technical Field
Embodiments of the subject matter disclosed herein relates to batteries. Other embodiments relate to packaging configurations for multi-cell array batteries.
2. Discussion of Art
Multi-celled batteries for storing energy are often packaged in a manner that makes it difficult to manufacture, and later service, the batteries. For example, a vacuum can be pulled between an inner battery box, housing an array of electrochemical cells, and an outer battery housing for thermal insulating purposes. The inner battery box can be sealed inside the outer battery box via welding to maintain the vacuum. As such, the outer battery housing is typically cut open to service elements within the outer battery housing, destroying the outer battery housing and, possibly, other elements as well.
Furthermore, during the manufacturing process, the cells of the array of electrochemical cells are to be accurately positioned with respect to each other. Also, each cell can have an electrically insulating plasma coating applied, or the cells can have pieces of mica material placed between them to electrically insulate the cells from each other. Such positioning and insulating methods can add complexity to the manufacturing process and can add material to the battery, thus increasing the cost of the battery.
It would therefore be desirable to develop a battery with features and characteristics that make the battery more easily manufactured and serviced versus batteries that are currently available.
In an embodiment, a cell alignment structure for an electrochemical device is provided having an array of electrically insulating cell receptacles, each cell receptacle configured to receive and support at least a bottom portion of an electrochemical cell. The array of cell receptacles is configured to provide a determined spacing between adjacent electrochemical cells received, in the cell receptacles.
In an embodiment, an inner battery packaging assembly for an electrochemical device is provided having the cell alignment structure disclosed above herein. The inner battery packaging assembly also provides a base plate configured to be disposed below the cell alignment structure, and a cover configured to fit over the cell alignment structure and removably attach to the base plate.
In an embodiment, an outer battery packaging assembly is provided having the inner battery packaging assembly disclosed above herein and an outer support plate configured to be disposed below the inner battery packaging assembly. The outer battery packaging assembly also provides a thermal insulating material removably surrounding at least a portion of the inner battery packaging assembly. The outer battery packaging assembly further provides an outer battery cover configured to fit over the inner battery packaging assembly, and over the thermal insulating material, and removably attach to the outer support plate.
In an embodiment, an insulated cover for an electrochemical device is provided having an inner battery cover configured to fit over an inner battery assembly. The insulated cover also has an outer battery cover nested over the inner battery cover, where the outer battery cover is attached to a base portion of the inner battery cover along a perimeter portion of the outer battery cover forming a sealed space therebetween. The insulated cover also has a thermal insulating material occupying at least a portion of the sealed space.
In an embodiment, an electrochemical device is provided having an array of electrically insulating cell receptacles. The device also provides a plurality of electrochemical cells, the cells having bodies and top and bottom portions at distal ends of the bodies, wherein the bottom portion of the cells are respectively received in and supported by the cell receptacles. The device further provides a stabilizing section engaging the top portions of the cells, and a base plate positioned under the array of electrically insulating cell receptacles. The device also provides a cover positioned over the stabilizing section and being removably attached to the base plate.
Reference is made to the accompanying drawings in which particular embodiments of the invention are illustrated as described in more detail in the description below, in which:
FIGS. 17. 18A-18B, and 19A-19C illustrate an embodiment of a battery configuration that includes an outer battery cover and an inner battery cover that are integrated into a single cover with thermal insulation therebetween to form a vacuum lid “top hat” configuration.
Embodiments relate to packaging configurations for multi-cell array batteries that are operated at high temperatures (e.g., 300° C. or more). In general, a multi-cell array battery has an inner battery packaging assembly (containing a plurality of electrochemical cells) that resides within a larger (e.g., outer) battery packaging assembly. The inner and outer packaging assemblies are configured such that the assemblies and/or the multi-cell array battery are more easily manufactured and serviced than batteries that are currently available.
With reference to the drawings, like reference numerals designate identical or corresponding parts throughout the several views. However, the inclusion of like elements in different views does not mean a given embodiment necessarily includes such elements or that all embodiments of the invention include such elements.
Embodiments of such electrochemical cells can have dimensions of about 37 mm×27 mm×240 mm, any of which dimensions may vary by up to +/−50%, in accordance with various embodiments. In embodiments, the chemistry of a cell is of the sodium-metal-halide type, where NaCl and Ni are converted to Na and NiCl7 during battery charging. The energy capacity of a cell can range from about 30 amp*hours to about 250 amps*hours.
An array of cells can be packaged into a housing to form a battery having typical dimensions of about 400 mm×500 mm×300 mm, any of which dimensions may vary by up to +/−50%, in accordance with various embodiments. In accordance with various embodiments, cooling channels are provided within the battery having a height ranging from about 2 mm to about 50 mm. Similarly, the width of a cooling channel can range from about 2 mm to about 50 mm. The operating temperature range of the cells can range between about 270° C. and about 350° C. in accordance with various embodiments.
The cell insertion section 110 also includes an array 150 (mid-region array) of electrically insulating cell guides 151 acting as a mid-cell stabilizing portion. Each cell guide 151 aligns with a corresponding cell receptacle 131, and each cell guide 151 is configured to mechanically stabilize a mid portion of an electrochemical cell 140 received in one of the receptacles 131. The base array 130 and the mid-region-array 150 each provide a determined spacing between inserted, adjacent electrochemical cells and are connected by vertical posts 111 at the four corners of the arrays. In accordance with certain embodiments, the resultant spacing of adjacent cells 140 within the cell alignment structure 100 is 1-4 millimeters, for example. Other spacings are possible as well, in accordance with other embodiments.
In embodiments, the outer cover of a cell is conductive and is at the established negative electrical potential of the cell (i.e., is effectively the negative terminal of the cell). By being electrically insulating, the cell alignment structure 100 eliminates the need for placing electrically insulating sheets of mica between rows of cells 140, or for plasma coating the cells, for example. Furthermore, the cell alignment structure 100 provides mechanical support and stability for the cells, reduces vibration of the cells during operation, establishes a defined cell-to-cell separation (which allows for use of multi-cell circuit connectors), relieves stress on cell-to-cell circuit connections, provides for better thermal equilibrium by sharing heat between cells, and allows for easier assembly/disassembly of the battery,
The upper stabilizing section 120 is electrically insulating and is configured to fit over a top portion of the plurality of electrochemical cells 140 held by the cell insertion section 110. The upper stabilizing section 120 is further configured to accept electrodes 145 of the plurality of electrochemical cells therethrough (e.g., through apertures or channels in the section 120). For example, as shown in
In general, electrical connectors are provided to connect the electrodes 145 of the cells 140 in series, parallel, or some combination thereof. As an option, electrical connections can be embedded within the stabilizing section 120, providing the desired electrical connections between the electrodes 145 of the cells 140.
The cell alignment structure 100 can be an extruded structure (e.g., extruded aluminum that is coated with an electrically insulating material), an injection molded structure (e.g., silicone thermoset), a die-cast structure (e.g., diecast aluminum that is coated with an electrically insulating material), a folded structure (e.g., folded sheet metal that is coated with an electrically insulating material), a rolled structure, or a stamped structure, in accordance with various embodiments. Furthermore, the cell alignment structure 100 can be made of a plurality of stamped or formed parts which fit together or interlace together with or without attachments, or which are welded or glued together, for example, in accordance with various other embodiments.
Furthermore, the cell alignment structure 100 can be made of an anodized aluminum material, a silicone thermoset material, a porcelain-coated mild steel material, or some combination thereof, in accordance with various embodiments. Other materials are possible as well, in accordance with various other embodiments, as long as they provide an electrically insulating capability, either naturally or via an applied coating (e.g., an aluminum oxide coating) and can withstand the high temperatures (e.g., 350° C. or more) of the battery environment. In accordance with an embodiment, a first cell alignment structure may be configured to include complementary features (e.g., mating features), allowing a similar cell alignment structure to be stacked onto the first cell alignment structure.
In accordance with an embodiment, the bias devices 310 are built-in on (or otherwise attached to) all four sides of a cell receptacle 131 and all four sides of the cell guide 151 in an interleaved (interlaced) configuration 320 of bias devices as shown in
As an alternative to bias devices, an adhesive can be used to adhere the cells 140 into the cell receptacles 131. However, with bias devices, a cell can be readily removed from a cell receptacle whereas, with an adhesive, a cell may not be readily removed. Furthermore, the adhesive has to be thermally stable, even at the high temperatures (e.g., 300° C.) at which a battery is operated. Some examples of high temperature adhesives include Armco Ceramabond 668, Aremco Ceramabond 671, Rutland Black, and Deacon Crow Seal 4022.
As another example, the bottom portion of a cell 140 can be configured with a bolt 540 and the cell receptacle 131 can include an aperture for the bolt 540 to penetrate therethrough. A locking nut 550 can be threaded onto the bolt 540 to mate the cell 140 to the cell receptacle 131. Furthermore, a cell receptacle can be lined with a flexible, adhering material 560 that effectively grips the cell 140 when the cell 140 is inserted into the cell receptacle 131. Other mating configurations are possible as well, in accordance with various embodiments.
The dashed arrows in
The vertically oriented gaps in the cell alignment structure 630 can be deliberately formed (e.g., via molding, casting, integrated cooling panels or tubes), in accordance with various embodiments. Alternatively, the gaps in the cell alignment structure 630 can simply be a residual artifact of the manufacturing process of the structure 630. For example, referring to
In accordance with an embodiment, the interconnecting portions 730 snap and lock together as shown in
Each inner battery packaging assembly 1210 and 1220 includes a thermally insulating aerogel material 1240 above the heater 860, although other high temperature thermal insulators may be substituted. Furthermore, each inner battery packaging assembly 1210 and 1220 includes an inner box support frame 1250 configured to support the cells 840 in the cell alignment structure 810 on the base plate 820, and configured to mount to a stacking support frame 1260. The inner battery packaging assembly 1220 is mounted to the stacking support frame 1260 above the inner battery packaging assembly 1210 which is also mounted to the stacking support frame 1260. In accordance with an alternative embodiment, the inner box support frame 1250 of each of the inner battery packaging assemblies 1210 and 1220 includes complementary features (e.g., mating features), allowing the support frame 1250 of one assembly 1210 to mount to the support flame 1250 of the other assembly 1220. Such an alternative embodiment may allow the elimination of the stacking support frame 1260.
The entire stacked configuration 1200 is enclosed in an external enclosure 1270, and a high temperature, thermally insulating material (e.g., vacuum insulated panels, or aerogel) 1280 surrounds the interior sides of the external enclosure 1270 to thermally insulate the entire stacked configuration 1200. The bus bars 920 from each of the inner battery packaging assemblies 1210 and 1220 are routed out of the stacked configuration 1200 to a battery management system (BMS) 1290, in accordance with an embodiment. Alternatively, two BMS's can be provided, one for each inner battery packaging assembly.
The stacked configuration 1200 provides a modular configuration of inner battery packaging assemblies that can be easily assembled and serviced. Stacked configurations of three or more inner battery packaging assemblies are possible as well, in accordance with various other embodiments. Such dense vertical stacking reduces the outer surface area, minimizes the footprint, requires less insulation, and is more thermally efficient than having two separate, unstacked configurations, for example.
The assembly 1300 includes an inner battery packaging assembly 1310 (e.g., similar to the inner battery packaging assembly 800 of
The assembly 1300 also includes a removable outer battery cover 1340 configured to drop down and fit over the inner battery packaging assembly 1310, and over the surrounding thermal insulating material 1330, and removably attach to the outer support plate 1320 (e.g., via bolts 1321). In accordance with an embodiment, the battery cover 1340 is made of stainless steel, although other materials are possible as well. The removable cover allows service personnel to more readily access the insulating material and the inner battery packaging assembly.
The assembly 1300 further includes a battery management system (BMS) 1350 configured to be mounted to the outer battery cover 1340 (e.g., via bolts 1341) and to operatively interface with components disposed within the inner battery packaging assembly 1310 (e.g., via bus bar leads 1311, control signal electrical leads, monitored parameter electrical leads, voltage sensing wires, heater leads, etc., which are routed through the insulating material 1330). The bus bar leads 1311 can be insulated solid metal leads (e.g., flat or round), or insulated cables that are stranded and flexible, in accordance with certain embodiments.
In accordance with an embodiment, certain leads and wires can be routed through a cooling channel of the battery packaging assembly 1300 (e.g., a cooling channel of the inner battery packaging assembly 1310) to provide access for measurement of internal parameters of the packaging assembly. For example, a resistive thermal device (RID) or thermocouple can be located, within the inner battery packaging assembly 1310 for the purpose of measuring temperature. Wires from the RTD can be routed through a cooling channel and out to the BMS 1350. In accordance with an alternative embodiment, a dedicated channel that is not used for cooling can be configured within the battery packaging assembly 1300 to provide access for measurement of internal parameters. The BMS 1350 is the controller of the battery and serves to control temperature of the battery and the charging and discharging of the battery.
The stacked configuration 1600 includes five outer battery packaging assemblies 1300 vertically stacked using the rack assembly 1610. A bottom rack support plate 1630 serves to support the entire assembly 1600 and is bolted to the lowest sub-assembly 1620 through the lowest support plate 1320, in accordance with an embodiment. A top rack plate 1640 can be mounted to the upper-most sub-assembly 1620 at the top of the assembly 1600 for providing added stability and protection from above.
The stacked configuration 1600 provides a modular configuration of batteries that can be easily modified (i.e., batteries can be added or taken away) as application requirements change. Furthermore, the stacked configuration 1600 minimizes the footprint of the multiple packaging assemblies 1300. In accordance with an alternative embodiment, the outer packaging assembly is configured to have complementary features (e.g., mating features) allowing the outer packaging assembly to be vertically stacked within a rack with other similar battery packaging assemblies.
In accordance with an alternative embodiment, a battery configuration 1700 includes an outer battery cover 1710 and an inner battery cover 1720 that are integrated into a single cover with a thermal insulating material 1730 vacuum insulated panels) therebetween, as shown in
The integrated cover 1701 fits over an inner battery assembly 1740 having a battery tray assembly 1920 of electrochemical cells, mica sheets 1930, a heater 1910, etc. The inner battery assembly 1740 rests on a bottom thermal insulation layer 1750 above a bottom support plate 1760. In accordance with an embodiment, the integrated cover 1701 is bolted to the bottom support plate 1760 via perimeter bolts 1770, and the wiring 1780 (e.g., bus bar cables, heater leads, and the like) is routed out of the inner battery assembly 1740 through cut-outs 1790 in the bottom support plate 1760.
In any of the embodiments herein where elements are perpendicular, such elements may be generally perpendicular, meaning 90 degrees plus or minus 3 degrees, to account for relatively minor manufacturing variances/tolerances. Similarly, in any of the embodiments herein where elements are parallel, such elements may be generally parallel, meaning 0 degrees plus or minus 3 degrees, to account for relatively minor manufacturing variances/tolerances.
In the appended claims, the terms “including” and “having” are used as the plain language equivalents of the term “comprising”; the term “in which” is equivalent to “wherein.” Moreover, in the following claims, the terms “first,” “second,” “third,” “upper,” “lower,” “bottom,” “top,” etc, are used merely as labels, and are not intended to impose numerical or positional requirements on their objects. Further, the limitations of the following claims are not written in means-plus-function format and are not intended to be interpreted based on 35 U.S.C. §112, sixth paragraph, unless and until such claim limitations expressly use the phrase “means for” followed by a statement of function void of further structure. As used herein, an element or step recited in the singular and proceeded with the word “a” or “an” should be understood as not excluding plural of said elements or steps, unless such exclusion is explicitly stated. Furthermore, references to “one embodiment” of the present invention are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Moreover, unless explicitly stated to the contrary, embodiments “comprising,” “including,” or “having” an element or a plurality of elements having a particular property may include additional such elements not having that property. Moreover, certain embodiments may be shown as having like or similar elements, however, this is merely for illustration purposes, and such embodiments need not necessarily have the same elements unless specified in the claims.
As used herein, the terms “may” and “may be” indicate a possibility of an occurrence within a set of circumstances; a possession of a specified property, characteristic or function; and/or qualify another verb by expressing one or more of an ability, capability, or possibility associated with the qualified verb. Accordingly, usage of “may” and “may be” indicates that a modified term is apparently appropriate, capable, or suitable for an indicated capacity, function, or usage, while taking into account that in some circumstances the modified term may sometimes not be appropriate, capable, or suitable. For example, in some circumstances an event or capacity can be expected, while in other circumstances the event or capacity cannot occur—this distinction is captured by the terms “may” and “may be.”
This written description uses examples to disclose the invention, including the best mode, and also to enable one of ordinary skill in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differentiate from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.