Battery pack

Abstract

A battery pack includes a battery pack positive terminal, a battery pack negative terminal, a cell assembly, a bar strip, and an electrical path. The cell assembly includes battery cells. The bar strip has a collector tab and a battery tab. And the battery connecting piece is electrically connected with the battery cell closest to the current collection lug. An electrical path extends between the collector tab and the battery tab. The electrical path includes a first path portion extending between the collector tab and a region through which the battery tab passes, and a second path portion extending between the region through which the battery tab passes and the battery tab.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 487,083, filed on February 27, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to a rechargeable battery pack. More particularly, the present disclosure relates to a busbar for a battery pack having a plurality of battery cells. Background Art

[0004] In a battery pack with multiple cells, the cells must be coupled to the terminals and any other components of the pack. A common problem with these connections is that one cell may have a shorter path, and therefore, the resistance between the cell and the component to which it is connected is different than the other cells in the pack. This imbalance in the connections to each cell can result in hot spots due to the different resistance of the electrical paths from one or more cells. Hot spots can lead to unbalanced performance between cells, premature failure of the battery pack, and even fire. Utility Model Content

[0005] In some aspects, the technology described herein relates to a battery pack comprising: a positive battery terminal; a negative battery terminal; a cell assembly having a plurality of battery cells; a battery strip having a current collector tab and a battery connecting tab, the battery connecting tab being electrically connected to the battery cell closest to the current collector tab; and an electrical path extending between the current collector tab and the battery connecting tab, the electrical path comprising a first path portion extending between the current collector tab and an area passing through the battery connecting tab and a second path portion extending between the area passing through the battery connecting tab and the battery connecting tab.

[0006] In some aspects, the technology described herein relates to a battery pack wherein the battery band includes an inner band and an outer band.

[0007] In some aspects, the technology described herein relates to a battery pack in which an inner band is electrically connected to an outer band at a weld, and a first path portion is connected to a second path portion at the weld.

[0008] In some aspects, the technology described herein relates to a battery pack in which an inner band is formed of a first material and an outer band is formed of a second, different material.

[0009] In some aspects, the technology described herein relates to a battery pack in which the battery strip is an integral unit.

[0010] In some aspects, the technology described herein relates to a battery pack wherein the tab strip includes another battery connection tab electrically connected to the battery cell farthest from the current collector tab, and the battery pack further includes another electrical path extending between the current collector tab and the other battery connection tab.

[0011] In some aspects, the technology described herein relates to a battery pack in which a resistance of another electrical path is within 10% of a resistance of the electrical path.

[0012] In some aspects, the technology described herein relates to a battery pack in which a resistance of another electrical path is within 5% of a resistance of the electrical path.

[0013] In some aspects, the technology described herein relates to a battery pack, wherein the tab strip includes an intermediate battery connecting plate that is electrically connected to an intermediate battery cell located between a battery cell closest to a current collecting tab and a battery cell farthest from the current collecting tab, and the battery pack further includes an intermediate electrical path extending between the current collecting tab and the intermediate battery connecting plate.

[0014] In some aspects, the technology described herein relates to a battery pack in which the resistance of an intermediate electrical path is within 10% of the resistance of the electrical path.

[0015] In some aspects, the technology described herein relates to a battery pack, comprising: a battery pack positive terminal; a battery pack negative terminal; a cell assembly having a first battery cell, a second battery cell, and a third battery cell; and a flap band having a battery connection area and a slender extension, the battery connection area having a petal connected to the first battery cell and another petal connected to the second battery cell and / or the third battery cell, the petal and the other petal being connected at the petal connection area, and the slender extension being connected to the battery connection area adjacent to the petal connection area.

[0016] In some aspects, the technology described herein relates to a battery pack, wherein the elongated extension has a current collection tab, and the current collection tab is configured to be electrically connected to one of a battery pack positive terminal and a battery pack negative terminal.

[0017] In some aspects, the technology described herein relates to a battery pack in which a first battery cell is a first distance from an elongated extension, a third battery cell is a third distance from the elongated extension, and the first distance is shorter than the third distance.

[0018] In some aspects, the technology described herein relates to a battery pack wherein a first battery cell is configured to define a first electrical path from the first battery cell to an elongated extension, the first electrical path having a first voltage, and a third battery cell is configured to define a third electrical path from the third battery cell to the elongated extension, the third electrical path having a third voltage, and the third voltage is within 5% of the first voltage.

[0019] In some aspects, the technology described herein relates to a battery pack in which a flap strip has a mounting tab located between a petal and another petal.

[0020] In some aspects, the technology described herein relates to a battery pack comprising: a tab strip having a current collecting tab and a plurality of battery connecting tabs; and a plurality of battery cells connected to the plurality of battery connecting tabs of the tab strip, wherein each of the plurality of battery cells is configured to transfer electricity along a corresponding electrical path through a corresponding battery connecting tab among the plurality of battery connecting tabs to the current collecting tab, each corresponding electrical path having a path resistance, and a maximum path resistance being less than 170% of a minimum path resistance.

[0021] In some aspects, the technology described herein relates to a battery pack in which a maximum path resistance is less than 140% of a minimum path resistance.

[0022] In some aspects, the technology described herein relates to a battery pack in which a maximum path resistance is less than 130% of a minimum path resistance.

[0023] In some aspects, the technology described herein relates to a battery pack in which a maximum path resistance is less than 110% of a minimum path resistance.

[0024] In some aspects, the technology described herein relates to a battery pack in which a maximum path resistance is less than 106% of a minimum path resistance.

[0025] Features and aspects of the present disclosure will become apparent through consideration of the following detailed description and accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a schematic cross-sectional view of a battery pack according to embodiments disclosed herein.

[0027] Figure 2A and 2B It is a three-dimensional diagram of a battery pack.

[0028] Figure 3A is a front view of a negative terminal strip according to embodiments disclosed herein.

[0029] Figure 3Bis a perspective view of a positive terminal strip according to embodiments disclosed herein.

[0030] Figure 3C yes Figure 3A Schematic diagram of the electrical path of the negative terminal band.

[0031] Figure 4 It shows that FIG. 3A to FIG. 3C A graph of the temperature of cells in a battery pack with end bands.

[0032] Figure 5A With electrical bypass Figure 3A A stereogram of the negative terminal strip.

[0033] Figure 5B With two electrical bypass paths Figure 3B A stereogram of the positive terminal strip.

[0034] Fig. 6A yes Figure 5A Front view of the negative terminal strip attached to the battery pack.

[0035] Figure 6B yes Figure 5B Front view of the positive terminal strip attached to the battery pack.

[0036] Figure 7 It shows that FIG. 5A to FIG. 5B A graph of the temperature of cells in a battery pack with end bands.

[0037] Fig. 8A It shows that FIG. 3A to FIG. 3C Thermal map of the cell temperatures in a battery pack with end bands.

[0038] Figure 8B It shows that Figure 5A and Figure 5B Thermal map of the cell temperatures in a battery pack with end bands.

[0039] Fig. 9A and Fig. 9B is a front view of another embodiment of a negative terminal strap according to embodiments disclosed herein.

[0040] Fig. 10A and Fig. 10B are front and back views of another embodiment of a negative terminal strap according to embodiments disclosed herein.

[0041] Fig.11 yes Fig. 10A and Fig. 10B Front view of the outer band of the negative end band.

[0042] Fig.12 yes Fig. 10A and Fig. 10BRear view of the inner band of the negative end band.

[0043] Fig.13 yes Fig. 10A and Fig. 10B Schematic rear view of the electrical pathway with the negative terminal strip.

[0044] Fig.14 It shows Fig. 10A and Fig. 10B A graph of the resistance values ​​of the electrical path with the negative terminal.

[0045] Fig.15A and Fig. 15B are front and back views of another embodiment of a positive terminal strip according to embodiments disclosed herein.

[0046] Fig.16 yes Fig.15A and Fig. 15B Front view of the outer band of the positive end band.

[0047] Fig.17 yes Fig.15A and Fig. 15B Rear view of the inner band of the positive end band.

[0048] Fig.18A and Fig.18B yes Fig.15A and Fig. 15B Schematic diagram of the electrical path of the positive terminal band.

[0049] Fig.19 It shows Fig.15A and Fig. 15B A graph of the resistance values ​​of the electrical path with the positive terminal.

[0050] Fig. 20A and Fig. 20B are front and back views of another embodiment of a positive terminal strip according to embodiments disclosed herein.

[0051] Fig.21A and Fig.21B yes Fig. 20A and Fig. 20B Schematic diagram of the electrical path of the positive terminal band.

[0052] Fig. 22 It shows Fig.24A and Fig. 24B A graph of the resistance values ​​of the electrical path with the positive terminal.

[0053] Fig.23A is a front view of another embodiment of a positive terminal strip according to embodiments disclosed herein.

[0054] Fig. 23B It shows Fig.21A and Fig.21B as well as Fig.23A A graph of the resistance values ​​of the electrical path with the positive terminal.

[0055] FIG. 24A to FIG. 24B are front and back views of another embodiment of a positive terminal strip according to embodiments disclosed herein.

[0056] Fig.25A and Fig.25B yes Fig.24A and Fig. 24B Schematic diagram of the electrical path of the positive terminal band.

[0057] Fig.26A and Fig.26B are front and back views of another embodiment of a positive terminal strip according to embodiments disclosed herein.

[0058] Fig.27A and Fig.27B yes Fig.26A and Fig.26B Schematic diagram of the electrical path of the positive terminal band.

[0059] Fig.28 is a front view of an embodiment of a positive end strap according to embodiments disclosed herein.

[0060] Fig.29 yes Fig.28 Schematic diagram of the electrical path of the negative terminal band.

[0061] Fig.30 is a front view of another embodiment of a negative terminal strap according to embodiments disclosed herein.

[0062] Fig.31 yes Fig.30 Schematic diagram of the electrical path of the negative terminal band.

[0063] Fig.32A and Fig.32B are front and back views of another embodiment of a positive terminal strip according to embodiments disclosed herein.

[0064] Fig.33A and Fig.33B yes Fig.32A and Fig.32B Schematic diagram of the electrical path of the positive terminal band. DETAILED DESCRIPTION

[0065] Before explaining any embodiment of the present disclosure in detail, it should be understood that the present disclosure is not limited in its application to the construction details and component arrangements set forth in the following description or shown in the accompanying drawings. The present disclosure can have other embodiments and can be implemented or performed in various ways. In addition, it should be understood that the words and terms used herein are for descriptive purposes and should not be considered as limiting.

[0066] Figure 1 is a schematic diagram of an exemplary battery pack 10. The battery pack 10 includes a housing 14 supporting a cell assembly 18, a positive battery terminal 22, and a negative battery terminal 26. The battery pack 10 is configured to be electrically connected to a load (e.g., a power tool) through the positive battery terminal 22 and the negative battery terminal 26.

[0067] The monomer assembly 18 includes a plurality of monomers 30 and (in Figure 2A 1 and discussed in more detail below). In the illustrated embodiment, the monomer assembly 18 includes fifteen monomers. More specifically, the illustrated monomer assembly 18 includes three rows (AC) and five columns (1-5) of monomers 30. Each of the plurality of monomers 30 may be named based on the row and column in which the monomer is located (e.g., 1A-5C). Each monomer 1A-5C includes a monomer positive terminal 34 and a monomer negative terminal 38. In other embodiments, the monomer assembly 18 may have a different number of monomers.

[0068] refer to Figure 2A and Figure 2B , the cell bar-piece assembly 40 includes a plurality of bar-piece straps 46. Each bar-piece strap 46 electrically connects the cells 30 in each column 1-5 so that electricity can be transmitted from the cells 30 to the bar-piece straps. The plurality of bar-piece straps 46 include a positive terminal strap 50 and a negative terminal strap 54. The positive terminal strap 50 is connected to the cell positive terminal 34 of the battery cells 30 in the first column (e.g., cells 1A, 1B, 1C), and the negative terminal strap 54 is connected to the cell negative terminal 38 of the battery cells 30 in the fifth column (e.g., cells 5A, 5B, 5C). The positive terminal strap 50 and the negative terminal strap 54 may have a different configuration from other bars in the plurality of bar-piece straps 46.

[0069] The cell bar assembly 40 may be connected to the terminal bar assembly 42 such that an electrical path exists between the cells 30 and the battery pack terminals 22 , 26 .

[0070] Figure 3A A negative terminal strip 54 is shown, and Figure 3BA positive end strap 50 is shown. The negative end strap 54 and the positive end strap 50 can have similar components, but they can have different configurations (e.g., body shapes). The end straps 50, 54 include a strap body 58 that connects a plurality of battery connection tabs 62 and extensions 70. The strap body 58 can also include a set of mounting tabs or mounting holes 66 that secure the end straps 50, 54 to the battery pack 10 and the cell assembly 18. The strap body 58 can have a generally flat or sheet-like shape.

[0071] The plurality of battery connection tabs 62 include at least a first battery connection tab 90 connected to the battery cells 30 in the first row (e.g., 1A, 5A), a second battery connection tab 94 connected to the battery cells 30 in the second row (e.g., 1B, 5B), and a third battery connection tab 98 connected to the battery cells in the third row (e.g., 1C, 5C). Some of the plurality of battery connection tabs 62 may form the outer peripheral edge of the strip 58 (e.g., the third battery connection tab 98), and some of the plurality of battery connection tabs 62 may be disposed in the middle of the strip 58 (e.g., the first battery connection tab 90). The battery connection tabs 62 may be recessed relative to the strip 58 so that the plurality of battery connection tabs 62 may be connected to the battery cells 30. In some embodiments, each of the battery connection tabs 62 has a semicircular shape. In other embodiments, each or some of the battery connection tabs 62 may include a contact dimple 102 ( Fig. 9A and Fig. 9B ) and / or a slit 106 that increases the flexibility of the battery connecting piece.

[0072] The extension 70 defines an end of the strip 58 opposite the third battery connection tab 98. The extension 70 may include a current collector tab 78 disposed at the end of the extension 70. The current collector tab 78 electrically connects the extension 70 and the end strips 50, 54 to the terminal bar assembly 42, so that a plurality of battery cells (e.g., 1A-1C or 5A-5C) connected to the end strips 50, 54 are electrically connected to the battery pack positive terminal 22 or the battery pack negative terminal 26.

[0073] refer to Figure 3C The end bands 50, 54 have: a first power path or first electrical pathway 110 extending between the first battery connection tab 90 and the current collector tab 78; a second power path or second electrical pathway 114 extending between the second battery connection tab 94 and the current collector tab 78; and a third power path or third electrical pathway 118 extending between the third battery connection tab 98 and the current collector tab 78. Each electrical pathway 110, 114, 118 has a pathway resistance value.

[0074] Each electrical path 110, 114, 118 in the negative terminal strip 54 has its own path resistance value. The first electrical path 110 has a first resistance of 646 micro-ohms. The second electrical path 114 has a second resistance of 951 micro-ohms. The third electrical path 118 has a third resistance of 1044 micro-ohms. The current bias of the first resistance is 75.4%; the current bias of the second resistance is 16.14%; and the current bias of the third resistance is 8.46%. The maximum path resistance (e.g., the third resistance) is less than 170% of the minimum path resistance (e.g., the first resistance). The maximum path resistance is about 161% of the minimum path resistance.

[0075] Each electrical path 110, 114, 118 in the positive terminal strip 50 has its own path resistance value. The first electrical path 110 has a first resistance of 282.48 micro-ohms. The second electrical path 114 has a second resistance of 531.84 micro-ohms. The third electrical path 118 has a third resistance of 802.66 micro-ohms. The current bias of the first resistance is 69.4%; the current bias of the second resistance is 21.59%; and the current bias of the third resistance is 9%. The maximum path resistance (e.g., the third resistance) is about 284% of the minimum path resistance (e.g., the first resistance).

[0076] Figure 4 and Figures 7 to 8B The advantage of having electrical paths with similar resistance in the end straps is illustrated. Figure 4 and Fig. 8A The temperature of the end strips having electrical paths of non-uniform lengths (eg, end strips 50, 54) are shown. The temperature of cells 1A and 5A is higher than the remaining cells because these cells have shorter electrical paths and lower resistance than the remaining cells.

[0077] In order to reduce the temperature difference between the monomers 1A, 5A and the remaining monomers, an electrical bypass 122 ( FIG. 5A to FIG. 6B ). The electrical bypass 122 connects the third battery connection piece 98A to the extension 70A. The electrical bypass 122 serves as another electrical path between the third battery connection piece 98A and the extension 70A, thereby reducing the resistance in each path. The electrical bypass 122 makes the electrical paths have similar resistance. In some embodiments, the end bands 50A, 54A can have two electrical bypasses 122 to further reduce the resistance of the electrical path from the third battery connection piece 98A to the extension 70A.

[0078] Figure 7 and Figure 8BThe temperature of cells connected to end straps 50A, 54A via electrical bypass 122 is shown. The temperature of cells 1A and 5A is closer to the temperature of the remaining cells. When the electrical paths from the battery tabs to the current collector tabs have similar resistance, the temperature differences between cells are minimized.

[0079] refer to Fig. 9A and Fig. 9B , another embodiment of a negative end band 1054 is shown. Many features of the negative end band 1054 are similar to the features discussed above in connection with the first embodiment of the negative end band 54. As such, many of these features will not be discussed in detail below. Features similar to those discussed above will be labeled with reference numerals that are 1000 higher in value than the corresponding features discussed above.

[0080] The negative terminal strip 1054 has an integral strip body 1058 with a battery connection region 1126 and a current collection region 1130. The battery connection region 1126 includes a first battery connection tab 1090, a second battery connection tab 1094, and a third battery connection tab 1098. The current collection region 1130 includes an extension 1070 with a current collection tab 1078. The strip body 1058 has a curved shape so that the battery connection region 1126 is located on one plane and the current collection region 1130 is located on a second plane. In the illustrated embodiment, the battery connection region 1126 is perpendicular to the current collection region 1130.

[0081] Negative terminal strap 1054 has a first electrical pathway 1110 extending between first battery connection tab 1090 and current collector tab 1078 , a second electrical pathway 1114 extending between second battery connection tab 1094 and current collector tab 1078 , and a third electrical pathway 1118 extending between third battery connection tab 1098 and current collector tab 1078 .

[0082] The first battery connecting piece 1090 is a first length away from the current collecting tab 1078. The second battery connecting piece 1094 is a second length away from the current collecting tab 1078. The third battery connecting piece 1098 is a third length away from the current collecting tab 1078. The second length and the third length are within 10% of the first length. In some embodiments, the distances between the battery connecting pieces 1090, 1094, 1098 and the current collecting tab 1078 are equal, so that the electrical paths 1110, 1114, 1118 have similar resistances.

[0083] refer to FIG. 10A to FIG. 14 , another embodiment of a negative end band 2054 is shown. Many features of the negative end band 2054 are similar to the features discussed above in connection with the first embodiment of the negative end band 54. As such, many of these features will not be discussed in detail below. Features similar to those discussed above will be labeled with reference numerals that are 2000 higher in value than the corresponding features discussed above.

[0084] The negative terminal strap 2054 includes a strap body 2058 having an inner strap 2134 and an outer strap 2138. The inner strap 2134 is connected to the outer strap 2138 by a weld 2142. The inner strap 2134 is electrically connected to the outer strap 2138 only at the weld 2142. The inner strap 2134 is adjacent to the cell assembly 18. The inner strap 2134 defines a cell connection region 2126 and the outer strap defines a current collection region 2130.

[0085] The inner band 2134 includes a first battery connection piece 2090, a second battery connection piece 2094, and a third battery connection piece 2098. The first battery connection piece 2090 is electrically connected to the battery cell (e.g., battery cell 5A) closest to the current collecting tab 2078. The second battery connection piece 2094 is electrically connected to the middle battery cell (e.g., battery cell 5B). The third battery connection piece 2098 is electrically connected to the battery cell (e.g., battery cell 5C) farthest from the current collecting tab 2078.

[0086] The first battery connecting piece 2090 is a first length away from the weld 2142. The second battery connecting piece 2094 is a second length away from the weld 2142. The third battery connecting piece 2098 is a third length away from the weld 2142. The second length and the third length are within 10% of the first length. In some embodiments, the battery connecting pieces 2090, 2094, 2098 are at equal distances from the weld 2142.

[0087] The outer band 2138 includes an extension 2070 having a current collector tab 2078 and a cutout portion 2146. In the illustrated embodiment, the cutout portion 2146 is aligned with the first battery connection tab 2090. The cutout portion 2146 reduces the amount of material in the outer band 2138. The outer band 2138 extends along the inner band 2134 to an area adjacent to the second battery connection tab 2094.

[0088] Negative terminal strap 2054 has a first electrical pathway 2110 extending between first battery connection tab 2090 and current collector tab 2078 , a second electrical pathway 2114 extending between second battery connection tab 2094 and current collector tab 2078 , and a third electrical pathway 2118 extending between third battery connection tab 2098 and current collector tab 2078 .

[0089] The first electrical path 2110 includes a first path portion 2110A and a second path portion 2110B connected at the weld 2142. The first path portion 2110A extends between the collector tab 2078 and the region passing through the first battery connection tab 2090. More specifically, the first path portion 2110A extends between the collector tab 2078 and the weld 2142. The second path portion 2110B extends between the region passing through the first battery connection tab 2090 and the first battery connection tab 2090. More specifically, the second path portion 2110B extends between the weld 2142 and the first battery connection tab 2090.

[0090] Second electrical pathway 2114 includes first pathway portion 2114A and second pathway portion 2114B connected at weld 2142. First pathway portion 2114A may be identical to first pathway portion 2110A of first electrical pathway 2110. Second pathway portion 2114B may extend between weld 2142 and second battery connection tab 2094.

[0091] The third electrical pathway 2118 includes a first path portion 2118A and a second path portion 2118B connected at the weld 2142. The first path portion 2118A may be the same as the first path portion 2110A of the first electrical pathway 2110. The second path portion 2118B may continue to extend between the weld 2142 and the third battery connection tab 2098.

[0092] The first electrical pathway 2110 has a first length. The second electrical pathway 2114 has a second length. The third electrical pathway 2118 has a third length. The second length and the third length are within 10% of the first length. In some embodiments, the second length and the third length are within 5% of the first length. In some embodiments, the third length is within 1% of the first length.

[0093] Each electrical path 2110, 2114, 2118 has its own path resistance value. The first electrical path 2110 has a first resistance of 759.11 micro-ohms. The second electrical path 2114 has a second resistance of 721.15 micro-ohms. The third electrical path 2118 has a third resistance of 759.98 micro-ohms. The current bias of the first resistor is 34%; the current bias of the second resistor is 33%; the current bias of the third resistor is 32%. The maximum path resistance (e.g., the third resistance) is less than 110% of the minimum path resistance (e.g., the second resistance). The maximum path resistance is less than 106% of the minimum path resistance. The maximum resistance may be within 105% of the minimum path resistance. The maximum resistance may be within 103% of the minimum path resistance. The maximum resistance may be within 101% of the minimum path resistance. The maximum resistance may not exceed 100% of the minimum resistance.

[0094] refer to FIG. 15A to FIG. 19 , another embodiment of a positive end band 2050 is shown. Many features of the positive end band 2050 are similar to the features discussed above in connection with the first embodiment of the positive end band 50. As such, many of these features will not be discussed in detail below. Features similar to those discussed above will be labeled with reference numerals that are 2000 higher in value than the corresponding features discussed above.

[0095] The positive terminal band 2050 includes a band body 2058 having an inner band 2134 and an outer band 2138. The inner band 2134 is electrically connected to the outer band 2138 by a first weld 2142 and a second weld 2166. The inner band 2134 is adjacent to the cell assembly 18. The inner band 2134 defines the battery connection area 2126 and the outer band defines the collector area 2130. In the illustrated embodiment, the first weld 2142 has a generally circular shape, while the second weld 2166 is smaller and generally rectangular in shape. In other embodiments, the first weld 2142 may be smaller than the second weld 2166 or the same size as the second weld. In other embodiments, the first weld 2142 and the second weld 2166 may have other shapes (e.g., square, diamond, oval, etc.). In other embodiments, the first weld 2142 and the second weld 2166 may have the same shape.

[0096] The inner band 2134 includes a first battery connection tab 2090 (e.g., the closest battery connection tab), a second battery connection tab 2094 (e.g., the middle battery connection tab), and a third battery connection tab 2098 (e.g., the farthest battery connection tab). The first battery connection tab 2090 and the second battery connection tab 2094 are positioned so that they extend toward the extension 2070, while the third battery connection tab 2098 is positioned so that it extends away from the extension 2070. The first weld 2142 is positioned between the first battery connection tab 2090 and the second battery connection tab 2094 adjacent to the second battery connection tab 2094. The second weld 2166 is located on the other side of the second battery connection tab 2094.

[0097] The outer band 2138 includes an extension 2070 having a current collector tab 2078 and a plurality of cutout portions 2146. The extension 2070 is opposite the third battery connection tab 2098. In the illustrated embodiment, one of the plurality of cutout portions 2146 is aligned with the first battery connection tab 2090, and another of the plurality of cutout portions 2146 is aligned with the mounting hole 2066 so that the mounting pin can extend through the outer band 2138 and the inner band 2134. The plurality of cutout portions 2146 reduces the amount of material in the outer band 2138. The outer band 2138 extends along the inner band 2134 to the second battery connection tab 2094.

[0098] Positive terminal strip 2050 has a first electrical pathway 2110 extending between first battery connection tab 2090 and current collector tab 2078 , a second electrical pathway 2114 extending between second battery connection tab 2094 and current collector tab 2078 , and a third electrical pathway 2118 extending between third battery connection tab 2098 and current collector tab 2078 .

[0099] The first electrical path 2110 includes a first path portion 2110A and a second path portion 2110B connected at the weld 2142. The first path portion 2110A extends between the current collector tab 2078 and the weld 2142. The second path portion 2110B extends between the weld 2142 and the first battery connection tab 2090.

[0100] The second electrical path 2114 includes a left path having a first path portion 2114A and a second path portion 2114B and a right path having a first path portion 2114C and a second path portion 2114D. The first path portion 2114A and the second path portion 2114B are connected at a first weld 2142, and the first path portion 2114C and the second path portion 2114D are connected at a second weld 2166. The first path portion 2114A extends between the collector tab 2078 and the first weld 2142, and the first path portion 2114C extends between the collector tab 2078 and the second weld 2166. The first path portion 2114A of the left path may be the same as the first path portion 2110A of the first electrical path 2110. The first path portion 2114C of the right path may be located on the opposite side of the second battery connection tab 2094. The second path portion 2114B may extend between the first weld 2142 and the second battery connection tab 2094 , and the second path portion 2114D may extend between the second weld 2166 and the second battery connection tab 2094 .

[0101] The third electrical pathway 2118 includes a first path portion 2118A and a second path portion 2118B connected at the weld 2142. The first path portion 2118A may be the same as the first path portion 2110A of the first electrical pathway 2110. The second path portion 2118B may continue to extend between the weld 2142 and the third battery connection tab 2098.

[0102] The first electrical pathway 2110 has a first length. The second electrical pathway 2114 has a second length. The third electrical pathway 2118 has a third length. The third length is within 10% of the first length. In some embodiments, the third length is within 5% of the first length. In some embodiments, the third length is within 1% of the first length.

[0103] Each electrical path 2110, 2114, 2118 has its own path resistance value. The first electrical path 2110 has a first resistance of 923.21 micro-ohms. The second electrical path 2114 has a second resistance of 859.16 micro-ohms. The third electrical path 2118 has a third resistance of 867.91 micro-ohms. The current bias of the first resistor is 34%; the current bias of the second resistor is 33%; the current bias of the third resistor is 32%. The maximum path resistance (e.g., the first resistance) is less than 140% of the minimum path resistance (e.g., the second resistance). The maximum path resistance is less than 110% of the minimum path resistance. More specifically, the maximum resistance can be within 107% of the minimum path resistance.

[0104] refer to Fig. 20A Turning to FIG. 23 , another embodiment of a positive end band 3050 is shown. Many of the features of the positive end band 3050 are similar to the features discussed above in connection with the second embodiment of the positive end band 2050. As such, many of these features will not be discussed in detail below. Features similar to those discussed above will be labeled with reference numerals that are 1000 higher in value than the corresponding features discussed above.

[0105] The positive terminal strip 3050 includes a strip body 3058. The strip body 3058 has an inner strip 3134 and an outer strip 3138. The inner strip 3134 includes a first battery connection tab 3090, and the outer strip 3138 includes a second battery connection tab 3094, a third battery connection tab 3098, and an extension 3070 having a current collecting tab 3078. The inner strip 3134 extends between an area adjacent to the third battery connection tab 3098 and the current collecting tab 3078. The extension 3070 may be a stepped surface. The inner strip 3134 may be thicker than the outer strip 3138.

[0106] The inner band 3134 is connected to the outer band 3138 by a plurality of welds. The plurality of welds include a first group of welds 3194A partially surrounding the first battery connection tab 3090, a second group of welds 3194B adjacent to the second battery connection tab 3094, a third group of welds 3194C adjacent to the third battery connection tab 3098, a fourth group of welds 3194D between the second battery connection tab 3094 and the third battery connection tab 3098, and a fifth group of welds 3194E located on the extension 3070. The inner band 3134 may be electrically connected to the outer band 3138 only at the weld positions 3194A-3194E.

[0107] The positive terminal strip 3050 has a first electrical pathway 3110 extending between the first battery connection tab 3090 and the current collector tab 3078 , a second electrical pathway 3114 extending between the second battery connection tab 3094 and the current collector tab 3078 , and a third electrical pathway 3118 extending between the third battery connection tab 3098 and the current collector tab 3078 .

[0108] The first electrical path 3110 includes a first path portion 3110A extending along the outer weld 3138 and a second path portion 3110B extending along the inner band 3134. The first path portion 3110A of the first electrical path 3110 extends between the collector tab 3078 and the fifth set of welds 3194E. The second path portion 3110B of the first electrical path 3110 extends between the fifth set of welds 3194E and the first battery connector 3090.

[0109] The second electrical path 3114 extends along the outer tape 3138. The third electrical path 3118 extends along the outer tape 3138.

[0110] The first electrical pathway 3110 has a first length. The second electrical pathway 3114 has a second length. The third electrical pathway 3118 has a third length. The first electrical pathway 3110 may be longer than the first electrical pathway and the second electrical pathway.

[0111] Each electrical path 3110, 3114, 3118 has its own path resistance value. The first electrical path 3110 has a first resistance of 335.37 micro-ohms. The second electrical path 3114 has a second resistance of 532.79 micro-ohms. The third electrical path 3118 has a third resistance of 803.58 micro-ohms. The current bias of the first resistor is 62.87%; the current bias of the second resistor is 26.21%; and the current bias of the third resistor is 10.9%. The maximum path resistance (e.g., the third resistance) is less than 240% of the minimum path resistance (e.g., the first resistance).

[0112] Fig.23A and Fig. 23BThe resistance values ​​of the end band 3050' having an inner band 3134' formed of a first material and an outer band 3138' formed of a second, different material are compared to the resistance values ​​of the positive end band 3050. The dual material end band 3050' has a similar shape to the positive end band 3050. The resistance of the dual material end band 3050' is lower than the resistance of the positive end band 3050. The first material may be a material having a high resistance, such as FAS 680, and the second material may be a material having a low resistance, such as EFTEC 550. The dual material end band 3050' has a first electrical pathway 3110' extending between the first battery connecting tab 3090' and the current collecting tab 3078', a second electrical pathway 3114' extending between the second battery connecting tab 3094' and the current collecting tab 3078', and a third electrical pathway 3118' extending between the third battery connecting tab 3098' and the current collecting tab 3078'. The first electrical path 3110' has a first resistance of 306.3 micro-ohms. The second electrical path 3114' has a second resistance of 336.87 micro-ohms. The third electrical path 3118' has a third resistance of 486.65 micro-ohms. The current bias of the first resistor is 49.9%; the current bias of the second resistor is 35.36%; and the current bias of the third resistor is 14.74%. The maximum path resistance (e.g., the third resistance) is less than 160% of the minimum path resistance (e.g., the first resistance). More specifically, the maximum path resistance is less than 158% of the minimum path resistance.

[0113] refer to FIG. 24A to FIG. 25B , another embodiment of a positive end band 4050 is shown. Many features of the positive end band 4050 are similar to the features discussed above in connection with the third embodiment of the positive end band 3050. As such, many of these features will not be discussed in detail below. Features similar to those discussed above will be labeled with reference numerals that are 1000 higher in value than the corresponding features discussed above.

[0114] The positive terminal strip 4050 includes a strip body 4058. The strip body 4058 has an inner strip 4134 and an outer strip 4138. The inner strip 4134 includes a first battery connection tab 4090 and a second battery connection tab 4094, and the outer strip 4138 includes a third battery connection tab 4098 and an extension 4070 having a current collecting tab 4078. The inner strip 4134 extends between an area adjacent to the third battery connection tab 4098 and the current collecting tab 4078. The inner strip 4134 may be thicker than or have the same thickness as the outer strip 4138.

[0115] The inner band 4134 is connected to the outer band 4138 by a plurality of welds. The plurality of welds include a first group of welds 4194A adjacent to the first battery connection tab 4090, a second group of welds 4194B adjacent to the second battery connection tab 4094, a third group of welds 4194C adjacent to the third battery connection tab 4098, a fourth group of welds 4194D between the first battery connection tab 4090 and the second battery connection tab 4094, and a fifth group of welds 4194E located on the extension 4070. The inner band 4134 may be electrically connected to the outer band 4138 at weld positions 4194A-4194E. The first group of welds 4194A, the second group of welds 4194B, and the fourth group of welds 4194D may include only one weld.

[0116] The positive terminal strip 4050 has a first electrical path 4110 extending between the first battery connection tab 4090 and the current collector tab 4078, a second electrical path 4114 extending between the second battery connection tab 4094 and the current collector tab 4078, and a third electrical path 4118 extending between the third battery connection tab 4098 and the current collector tab 4078. Although not shown in the figure, the positive terminal strip 4050 may have more electrical paths extending through the weld points 4194A-4194E between the inner strip 4134 and the outer strip 4138.

[0117] The first electrical path 4110 includes a first path portion 4110A extending along the outer band 4138 and a second path portion 4110B extending along the inner band 4134. The first path portion 4110A of the first electrical path 4110 extends between the current collector tab 4078 and the fifth set of welds 4194E. The second path portion 4110B of the first electrical path 4110 extends between the fifth set of welds 4194E and the first battery connector 4090.

[0118] The second electrical path 4114 includes a first path portion 4114A extending along the outer band 4138 and a second path portion 4114B extending along the inner band 4134. The first path portion 4114A of the second electrical path 4114 extends between the collector tab 4078 and the fifth set of welds 4194E. The second path portion 4114B of the second electrical path 4114 extends between the fifth set of welds 4194E and the second battery connector 4094.

[0119] Unlike the first electrical pathway 4110 and the second electrical pathway 4114 which extend along both the outer band 4138 and the inner band 4134 , the third electrical pathway 4118 extends only along the outer band 4138 .

[0120] The strip body 4058 can be formed to increase the cross-sectional area between the second battery connection tab 4094 and the current collector tab 4078. The larger cross-sectional area reduces the resistance in the second electrical path 4114 and the resistance in the third electrical path 4118. In addition, the outer strip 4138 can have fewer cuts to reduce the resistance in the outer strip 4138 compared to other embodiments of the positive terminal strip (e.g., the positive terminal strip 2050).

[0121] refer to FIG. 26A to FIG. 27A , another embodiment of a positive end band 5050 is shown. Many features of the positive end band 5050 are similar to the features discussed above in connection with the third embodiment of the positive end band 3050. As such, many of these features will not be discussed in detail below. Features similar to those discussed above will be labeled with reference numerals that are 2000 higher in value than the corresponding features discussed above.

[0122] The positive terminal strip 5050 includes a strip body 5058. The strip body 5058 has an inner strip 5134 and an outer strip 5138. The inner strip 5134 includes a first battery connection tab 5090, and the outer strip 5138 includes a second battery connection tab 5094, a third battery connection tab 5098, and an extension 5070 having a current collecting tab 5078. The inner strip 5134 has a first leg extending between an area adjacent to the third battery connection tab 5098 and the current collecting tab 5078, and a second leg extending between an area adjacent to the second battery connection tab 5094 and the current collecting tab 5078. The extension 5070 may include a stepped surface.

[0123] The inner band 5134 is connected to the outer band 5138 by a plurality of welds. The plurality of welds include a first group of welds 5194A partially surrounding the first battery connection tab 5090, a second group of welds 5194B adjacent to the second battery connection tab 5094, a third group of welds 5194C adjacent to the third battery connection tab 5098, and a fourth group of welds 5194D located on the extension 5070. The inner band 5134 may be electrically connected to the outer band 5138 only at the weld positions 5194A-5194D.

[0124] The positive terminal strip 5050 has a first electrical pathway 5110 extending between the first battery connection tab 5090 and the current collector tab 5078 , a second electrical pathway 5114 extending between the second battery connection tab 5094 and the current collector tab 5078 , and a third electrical pathway 5118 extending between the third battery connection tab 5098 and the current collector tab 5078 .

[0125] The first electrical path 5110 includes a first path portion 5110A extending along the outer band 5138 and a second path portion 5110B extending along the inner band 5134. The first path portion 5110A of the first electrical path 5110 extends between the current collector tab 5078 and the fourth set of welds 5194D. The second path portion 5110B of the first electrical path 5110 extends between the fourth set of welds 5194D and the first battery connector 5090.

[0126] The second electrical path 5114 extends along the outer tape 5138. The third electrical path 5118 extends along the outer tape 5138.

[0127] refer to Fig.28 and Fig.29 , another embodiment of a positive end band 6050 is shown. Many features of the positive end band 6050 are similar to the features discussed above in connection with the first embodiment of the positive end band 1050. As such, many of these features will not be discussed in detail below. Features similar to those discussed above will be labeled with reference numerals that are 5000 higher in value than the corresponding features discussed above.

[0128] The positive terminal strip 6050 includes a strip body 6058. The strip body 6058 includes a battery connection portion 6126 and a current connection portion 6130. The strip body 6058 is a whole.

[0129] The battery connection portion 6126 includes a first lobe 6174 and a second lobe 6178. The first lobe 6174 includes a first battery connection piece 6090, and the second lobe 6178 includes at least a second battery connection piece 6094 or a third battery connection piece 6098. In the illustrated embodiment, the second lobe includes a second battery connection piece 6094 and a third battery connection piece 6098. The first lobe 6174 is connected to the second lobe 6178 at a lobe connection area 6182. The lobe connection area 6182 is located between the first battery connection piece 6090 and the second battery connection piece 6094. The first battery connection piece 6090 is a first distance from the current connection portion 6130. The second battery connection piece 6094 is positioned at a second distance from the current connection portion 6130. The third battery connection piece 6098 is a third distance from the current connection portion 6130. The length of the first distance can be the same as or longer than the length of the second distance. The first distance is longer than the third distance.

[0130] The current connection portion 6130 includes an extension portion 6070 and a current collecting tab 6078. The extension portion 6070 has a generally elongated shape. The current collecting tab 6078 is located at one end of the current connection portion 6130.

[0131] The battery connection portion 6126 and the current connection portion 6130 are connected to each other at a connection area 6190. The connection area 6190 is adjacent to the petal connection area 6182. The connection area 6190 is opposite to the current collection tab 6078 on the current connection portion 6130.

[0132] The positive terminal strip 6050 has a first electrical pathway 6110 extending between the first battery connection tab 6090 and the current collector tab 6078, a second electrical pathway 6114 extending between the second battery connection tab 6094 and the current collector tab 6078, and a third electrical pathway 6118 extending between the third battery connection tab 6098 and the current collector tab 6078. The third electrical pathway 6118 includes a first path extending along one side of the second battery connection tab 6094 and a second path extending along the other side of the second battery connection tab 6094. The electrical pathways 6110, 6114, 6118 can all have voltages within 5% of each other.

[0133] The strap 6058 may include a plurality of mounting protrusions or mounting holes 6066. One of the mounting holes 6066 may be located between the first lobe 6174 and the second lobe 6178. Another of the mounting holes 6066 may be located between the second battery connection tab 6094 and the third battery connection tab 6098.

[0134] refer to Fig.30 and Fig.31 , another embodiment of a positive end band 7050 is shown. Many features of the positive end band 7050 are similar to the features discussed above in connection with the sixth embodiment of the positive end band 6050. As such, many of these features will not be discussed in detail below. Features similar to those discussed above will be labeled with reference numerals that are 1000 higher in value than the corresponding features discussed above.

[0135] The positive terminal strip 7050 includes a strip body 7058. The strip body 7058 includes a first battery connection piece 7090, a second battery connection piece 7094, a third battery connection piece 7098, an extension 7070 having a current collection tab (not shown), and a mounting protrusion or mounting hole 7066.

[0136] The positive terminal strip 7050 has a first electrical path 7110 extending between the first battery connection piece 7090 and the extension 7070, a second electrical path 7114 extending between the second battery connection piece 7094 and the extension 7070, and a third electrical path 7118 extending between the third battery connection piece 7098 and the extension 7070. The third electrical path 7118 includes a first path extending along one side of the second battery connection piece 7094 and a second path extending along the other side of the second battery connection piece 7094.

[0137] The strip 7058 is designed so that the resistance of the first electrical path 7110 is the same as the resistance of the second and third electrical paths 7114, 7118. More specifically, because the first battery connection tab 7090 and the second battery connection tab 7094 are closer to the extension 7070, the strip 7058 is wider near the first battery connection tab 7090 and the second battery connection tab 7094. Because the third battery connection tab 7098 is farther from the extension 7070, the strip 7058 is narrower near the third battery connection tab 7098.

[0138] In addition, strip 7058 can be designed so that the amount of material used can be minimized. Strip 7058 is similar to strip 6058, but additional material is removed to form new strip 7058. Topology optimization tools can be used to help balance the electrical pathways and display additional, unnecessary material to form the shape of strip 7058.

[0139] refer to FIG. 32A to FIG. 33B , another embodiment of a positive end band 8050 is shown. Many features of the positive end band 8050 are similar to the features discussed above in connection with the third embodiment of the positive end band 3050. As such, many of these features will not be discussed in detail below. Features similar to those discussed above will be labeled with reference numerals that are 5000 higher in value than the corresponding features discussed above.

[0140] The positive terminal strip 8050 includes a strip body 8058. The strip body 8058 has an inner strip 8134 and an outer strip 8138. The inner strip 8134 includes a first battery connection tab 8090, and the outer strip 8138 includes a second battery connection tab 4094, a third battery connection tab 8098, and an extension 8070 having a current collecting tab 8078. The inner strip 8134 extends from an area above the second battery connection tab 8094 to the extension 8070.

[0141] The inner band 8134 is connected to the outer band 8138 by a plurality of welds. The plurality of welds include a first group of welds 8194A partially surrounding the first battery connection tab 8090, a second group of welds 8194B between the second battery connection tab 8094 and the first battery connection tab 8090, and a third group of welds 8194C located on the collector tab 8078. The inner band 8134 can be electrically connected to the outer band 8138 at the welding positions 8194A-8194B.

[0142] The positive terminal strip 8050 has a first electrical pathway 8110 extending between the first battery connection tab 8090 and the current collector tab 8078 , a second electrical pathway 8114 extending between the second battery connection tab 8094 and the current collector tab 8078 , and a third electrical pathway 8118 extending between the third battery connection tab 8098 and the current collector tab 8078 .

[0143] The first electrical path 8110 includes a first path portion 8110A extending along the outer band 8138 and a second path portion 8110B extending along the inner band 8134. The first path portion 8110A of the first electrical path 8110 extends between the current collector tab 8078 and the third set of welds 8194C. The second path portion 8110B of the first electrical path 8110 extends between the third set of welds 8194C and the first battery connector 8090.

[0144] The second electrical path 8114 extends along the outer tape 8138. The third electrical path 8118 extends along the outer tape 8138.

[0145] Various features of the present disclosure are set forth in the appended claims.

Claims

1. A battery pack, characterized in that: include: Battery pack positive terminal; Negative terminal of battery pack; A cell assembly having a plurality of battery cells; A battery strip having a current collecting tab and a battery connecting tab, wherein the battery connecting tab is electrically connected to a battery cell closest to the current collecting tab among the battery cells; as well as An electrical path extends between the current collector tab and the battery connecting tab, the electrical path comprising a first path portion extending between the current collector tab and a region passing through the battery connecting tab and a second path portion extending between the region passing through the battery connecting tab and the battery connecting tab.

2. The battery pack according to claim 1, wherein: The strip includes an inner strip and an outer strip.

3. The battery pack according to claim 2, wherein: The inner band is electrically connected to the outer band at the weld, and The first path portion is connected to the second path portion at the weld.

4. The battery pack according to claim 3, wherein: The inner band is formed from a first material and the outer band is formed from a second, different material.

5. The battery pack according to claim 1, wherein: The bar belt is a whole.

6. The battery pack according to claim 1, wherein: The tab strip includes another battery connecting tab electrically connected to the battery cell farthest from the current collecting tab among the battery cells, and The battery pack further includes another electrical pathway extending between the current collection tab and the other battery connection tab.

7. The battery pack according to claim 6, wherein: The resistance of the other electrical path is within 10% of the resistance of the electrical path.

8. The battery pack according to claim 6, wherein: The resistance of the other electrical path is within 5% of the resistance of the electrical path.

9. The battery pack according to claim 6, wherein: The tab strip includes an intermediate battery connecting piece, the intermediate battery connecting piece being electrically connected to an intermediate battery cell located between a battery cell closest to the current collecting tab and a battery cell farthest from the current collecting tab, and The battery pack further includes an intermediate electrical path extending between the current collection tab and the intermediate battery connector tab.

10. The battery pack according to claim 9, wherein: The resistance of the intermediate electrical path is within 10% of the resistance of the electrical path.

11. A battery pack, characterized in that: include: Battery pack positive terminal; Negative terminal of battery pack; A cell assembly, the cell assembly comprising a first battery cell, a second battery cell and a third battery cell; as well as A flap band having a battery connection area and a slender extension, the battery connection area having a flap connected to the first battery cell and another flap connected to the second battery cell and / or the third battery cell, the flap and the other flap are connected at the flap connection area, and the slender extension is connected to the battery connection area adjacent to the flap connection area.

12. The battery pack according to claim 11, wherein: The elongated extension has a current collecting tab, and The current collection tab is configured to be electrically connected to one of the battery positive terminal and the battery negative terminal.

13. The battery pack according to claim 11, wherein: The first battery cell is a first distance away from the elongated extension, The third battery cell is a third distance from the elongated extension, and The first distance is shorter than the third distance.

14. The battery pack according to claim 13, wherein: The first battery cell is configured to define a first electrical path from the first battery cell to the elongated extension, the first electrical path having a first voltage, The third battery cell is configured to define a third electrical path from the third battery cell to the elongated extension, the third electrical path having a third voltage, and The third voltage is within 5% of the first voltage.

15. The battery pack according to claim 11, wherein: The flap strip has a mounting protrusion located between the flap and the other flap.

16. A battery pack, characterized in that: include: A battery strip having a current collecting tab and a plurality of battery connecting tabs; as well as A plurality of battery cells connected to the plurality of battery connecting pieces of the bar strip, in, Each of the plurality of battery cells is configured to transmit power along a corresponding electrical path through a corresponding battery connection tab of the plurality of battery connection tabs to the current collection tab, Each corresponding electrical path has a path resistance, and The maximum path resistance is less than 170% of the minimum path resistance.

17. The battery pack according to claim 16, wherein: The maximum via resistance is less than 140% of the minimum via resistance.

18. The battery pack according to claim 17, wherein: The maximum via resistance is less than 130% of the minimum via resistance.

19. The battery pack according to claim 18, wherein: The maximum path resistance is less than 110% of the minimum path resistance.

20. The battery pack according to claim 19, wherein: The maximum path resistance is less than 106% of the minimum path resistance.

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