System and method for arranging battery cells based on groupings of prime numbers of cells connected in parallel

Abstract

An arrangement of cells for a battery module includes forming a basic unit of battery cells having a number of cells that equals a prime number, and the basic units are arranged to form the battery module. Each basic unit has three rows of cells arranged in a tangent arrangement, an inner row and adjacent outer rows, where the number of cells in the inner row and each of the outer rows is determined based on a breakdown of the prime number. The basic units are arranged with other basic units such that the cells of outer rows of adjacent units are in direct arrangement as are cells on the ends of rows of adjacent basic units. Battery modules arranged in this manner require fewer types of busbars to connect the cells of units in parallel and the units in series.

Description

SYSTEM AND METHOD FOR ARRANGING BATTERY CELLSBASED ON GROUPINGS OF PRIME NUMBERS OF CELLS CONNECTED IN PARALLELRELATED APPLICATION DATA

[0001] This application claims the benefit of priority of U.S. Provisional Patent Application Serial No. 63 / 605,040, filed December 1, 2023, and titled “System and Method for Arranging Battery Cells Based on Groupings of Prime Numbers of Cells Connected in Parallel”, which is incorporated by reference herein in its entirety.FIELD OF THE DISCLOSURE

[0002] The present disclosure generally relates to the field of battery modules. In particular, the present disclosure is directed to a system and method for arranging battery cells based on groupings of prime numbers of cells connected in parallel.BACKGROUND

[0003] At present, two arrangements are widely used for grouping cylindrical battery cells in battery modules. In the first, as illustrated in FIG. 1 (prior art), cells 104 (e.g., 104a, 104b) of battery module 100 are arranged perpendicular to each other (i.e., the included angle is 90 degrees) with equal spacing. The distance (B) between the centers of adjacent cells 104 is equal to the diameter of cylindrical cells (d) and the spacing (L) between the cells (i.e., B = d + L). When the spacing between adjacent cells 100 is zero, i.e., when L = 0, any battery cell can be tangent to, at most, four other cells. For example, cell 104a is tangent to cells 104b, 104c, 104d, and 104e. This arrangement will be referred to as a direct arrangement.

[0004] In the other common way to group battery cells, as illustrated in FIG. 2 (prior art), a battery module 200 includes battery cells 204 (e.g., 204a, 204b) that are arrayed at equal intervals where the included angle is 60 degrees. When the spacing is zero, i.e., L = 0, a battery cell is tangent to, at most, six adjacent batteries. For example, cell 204a is tangent to cells 204b-204g. This arrangement will be referred to as a tangent arrangement.SUMMARY OF THE DISCLOSURE

[0005] A battery module includes a plurality of cylindrical battery cells and a plurality of basic units, in which each of the plurality of basic units includes N of the plurality of cylindrical batterycells connected in parallel and in a tangent arrangement. Each of the plurality of basic units includes a first outer row, a second outer row, and a middle row between the first outer row and the second outer row, wherein N is a prime number greater than 7, wherein the first and second outer row each include N / 3 +1 battery cells if N / 3 is odd and N / 3 battery cells if N / 3 is even, where N / 3 is rounded down to a nearest whole number, wherein the middle row has N / 3 battery cells if N / 3 is odd and N / 3 + 1 battery cells if N / 3 is even, where N / 3 is rounded down to a nearest whole number, and wherein the plurality of basic units are arranged such that each cell of an outer row of a basic unit is in a direct arrangement with each cell of an outer row of an adjacent basic unit facing the outer row.

[0006] Additionally or alternatively, the plurality of cylindrical battery cells are connected with no more than three types of busbars.

[0007] Additionally or alternatively, N is 11.

[0008] Additionally or alternatively, there are 14 basic units connected in series.

[0009] Additionally or alternatively, each of the plurality of basic units is arranged such that the middle row does not extend beyond an end of the first outer row or the second outer row by more than a diameter of one of the battery cells and such that neither the first outer row nor the second outer row extends beyond the middle row by more than the diameter of one of the battery cells.

[0010] Additionally or alternatively, each cell of each outer row is in tangent arrangement with two cells of the middle row.

[0011] A method of arranging battery cells to form a battery module includes arranging a plurality of cylindrical battery cells into a plurality of basic units, wherein each of the plurality of basic units includes N cells connected in parallel and in a tangent arrangement, wherein N is a prime number greater than 7, wherein each of the plurality of basic units includes a first outer row, a second outer row, and a middle row between the first outer row and the second outer row, wherein the first and second outer row each include N / 3 +1 battery cells if N / 3 is odd and N / 3 battery cells if N / 3 is even, where N / 3 is rounded down to a nearest whole number, and wherein the middle row has N / 3 battery cells if N / 3 is odd and N / 3 + 1 battery cells if N / 3 is even, where N / 3 is rounded down to a nearest whole number, and arraying the plurality of basic units such that each cell of an outer rowof a basic unit is in a direct arrangement with each cell of an outer row of an adjacent basic unit facing the outer row. The plurality of cylindrical battery cells are connected with not more than three different types of busbars.

[0012] Additionally or alternatively, the plurality of basic units are arrayed such that endmost cells of basic units are in direct arrangement with respective endmost cells of adjacent basic units facing the endmost cells.

[0013] Additionally or alternatively, the N cells of each of the plurality of basic units are connected in parallel and connecting the plurality of basic units in series.

[0014] In another aspect, a method of arranging battery cells in a battery module includes selecting a number, N, of cells to group into each of a plurality of basic units, wherein N is a prime number greater than 7, and arranging, for each of the plurality of basic units, N cells into three subgroups of cells, including a first outside subgroup and a second outside subgroup, each having N / 3 +1 cells aligned if N / 3 is odd and N / 3 cells aligned if N / 3 is even, and a middle subgroup having N / 3 cells aligned if N / 3 is odd and N / 3 + 1 cells aligned if N / 3 is even, where N / 3 is rounded down to a nearest whole number. The N cells of each of the plurality of basic units are connected in parallel and the plurality of basic units are connected in series.

[0015] Additionally or alternatively, the connecting includes not more than three different types of busbars.

[0016] Additionally or alternatively, each cell of the first outside and the second outside subgroup of each basic unit is in tangent arrangement with two cells of the middle subgroup.

[0017] Additionally or alternatively, the plurality of basic units are arrayed such that each cell of an outer row of a basic unit is in a direct arrangement with each cell of an outer row of an adjacent basic unit facing the outer row.

[0018] Additionally or alternatively, the plurality of basic units are arrayed such that endmost cells of basic units are in direct arrangement with respective endmost cells of adjacent basic units facing the endmost cells.

[0019] In another aspect, a battery module includes a plurality of battery cells and a plurality of basic units, each of the plurality of basic units including N of the plurality of battery cells connected in parallel, wherein each of the plurality of basic units includes a first outer row, a second outer row, and a middle row between the first outer row and the second outer row, wherein N is a prime number greater than 7, wherein the first and second outer row each include N / 3 +1 battery cells if N / 3 is odd and N / 3 battery cells if N / 3 is even, where N / 3 is rounded down to a nearest whole number, wherein the middle row has N / 3 battery cells if N / 3 is odd and N / 3 + 1 battery cells if N / 3 is even, where N / 3 is rounded down to a nearest whole number, wherein each of the first and second outer row battery cells are in tangent arrangement with two inner row battery cells, and wherein the plurality of battery cells are connected with no more than three types of busbars.

[0020] Additionally or alternatively, each of the plurality of basic units is arranged such that the middle row does not extend beyond an end of the first outer row or the second outer row by more than a diameter of one of the battery cells and such that neither the first outer row nor the second outer row extends beyond the middle row by more than the diameter of one of the battery cells.

[0021] In addition, a battery module of the present disclosure may include a plurality of cylindrical battery cells and a plurality of basic units of cells formed from the plurality of cylindrical battery cells, wherein each of the plurality of basic units includes a group of N of the plurality of cylindrical battery cells connected in parallel and in a tangent arrangement, wherein each of the plurality of basic units includes a first outer row, a second outer row, and a middle row, wherein N is a prime number greater than 7, wherein the first and second outer row each include N / 3 +1 battery cells when N / 3 is odd and N / 3 battery cells when N / 3 is even, where N / 3 is rounded down to a nearest whole number, and wherein the middle row has N / 3 battery cells when N / 3 is odd and N / 3 + 1 battery cells when N / 3 is even, where N / 3 is rounded down to a nearest whole number. The plurality of basic units are arranged such that outer row battery cells of facing rows of adjacent basic units are aligned in a direct arrangement manner.

[0022] Additionally or alternatively, the plurality of basic units are arranged such that one or more corresponding battery cells at ends of rows of adjacent basic units are aligned in a direct arrangement manner.

[0023] Additionally or alternatively, the plurality of cylindrical battery cells are connected with no more than three types of busbars.

[0024] Additionally or alternatively, the plurality of basic units are aligned in two groups of 7.

[0025] Additionally or alternatively, each of the plurality of basic units is arranged such that the middle row does not extend beyond an end of the first outer row or the second outer row by more than a diameter of one of the battery cells and such that neither the first outer row nor the second outer row extends beyond the middle row by more than the diameter of one of the battery cells.

[0026] Additionally or alternatively, there are S basic units connected in series.

[0027] Additionally or alternatively, the plurality of basic units are aligned in two groups of S / 2.BRIEF DESCRIPTION OF THE DRAWINGS

[0028] For the purpose of illustrating the disclosed embodiments, the drawings show aspects thereof. It is to be understood, however, that the teachings of the present disclosure are not limited to the precise arrangements and instrumentalities shown in the drawings, wherein:

[0029] FIG. 1 is a schematic illustration of a prior art direct arrangement of battery cells in a battery module;

[0030] FIG. 2 is a schematic illustration of a prior art tangent arrangement of battery cells in a battery module;

[0031] FIG. 3 is a schematic illustration of a prior art direct arrangement of battery cells in a battery module in which groups of eleven cells are connected in parallel and the number of series connections is 14;

[0032] FIG. 4A is a schematic illustration of a top view of a prior art direct arrangement of battery cells showing different busbar types required to connect groups of eleven cells in parallel where the number of series connections is 14;

[0033] FIG. 4B is a schematic illustration of a bottom view of a prior art direct arrangement of battery cells showing different busbar types required to connect groups of eleven cells in parallel where the number of series connections is 14;

[0034] FIG. 5 is a schematic illustration of a prior art tangent arrangement of battery cells in a battery module in which groups of eleven cells are connected in parallel and the number of series connections is 14;

[0035] FIG. 6A is a schematic illustration of a top view of a prior art tangent arrangement of battery cells showing different busbar types required to connect groups of eleven cells in parallel where the number of series connections is 14;

[0036] FIG. 6B is a schematic illustration of a bottom view of a prior art tangent arrangement of battery cells showing different busbar types required to connect groups of eleven cells in parallel where the number of series connections is 14;

[0037] FIG. 7 depicts a basic unit of a group of battery cells arranged in rows in accordance with an aspect of the present disclosure;

[0038] FIG. 8 depicts another basic unit of a group of battery cells arranged in rows in accordance with an aspect of the present disclosure;

[0039] FIG. 9 depicts an arrangement of the basic units of the kind shown in FIGS. 7-8 in a battery module in accordance with an embodiment of the present disclosure;

[0040] FIGS. 10A-10B are schematic illustrations of a top view (10A) and bottom view (10B) of the battery module of FIG. 9 connected by only three different busbar types required to connect basic units of eleven cells in parallel where the number of series connections is 14;

[0041] FIG. 11 depicts another basic unit of a group of battery cells arranged in rows in accordance with an aspect of the present disclosure; and

[0042] FIG. 12 depicts twelve of the basic units of FIG. 11 arranged to form a module in accordance with an aspect of the present disclosure.DETAILED DESCRIPTION

[0043] There are drawbacks of both the direct arrangement and the tangent arrangement. For example, a battery module may be arranged such that 21,700 single battery cells are grouped in a way so that groups of 11 cells are connected in parallel and the number of series connections is 14. If the battery cell gap is assumed to be L = 1.5 mm throughout, the volume after grouping does not exceed length x width x height, which, in this example, is 450 mm x 190 mm x 85 mm (7,268 cm3).When the direct arrangement is used for such a module, a portion of which is depicted in FIG. 3 showing a battery module 300 with groups 311 (e.g., 311a, 311b) of eleven battery cells 304 (e.g., 304a), the volume is 448.5 mm x 178.5 mm x 70 mm (5,604 cm3). In this arrangement, in order to connect the cells 304 in groups 311 of 11 in parallel with 14 series connections, at least six different types of busbar are needed, as shown in FIGS. 4A (top view) (e.g., 316a-316b, 317a-317c, 318a- 318b, 319a) -4B (bottom view) (e.g., 320a-320d, 321a-321c). The lead-out copper bars 316 (e.g., 316a, 316b) are distributed at both ends of the module and will typically appear as if flipped vertically with respect to each other when viewed from above in a battery module.

[0044] When a tangent arrangement is used for this example set of cells, a battery module 400, as shown in FIG. 5, has a volume of 448.5 mm x 157.4 mm x 70 mm (4,942 cm3). Groups 411 (e.g., 411a, 41 lb) of eleven battery cells 404 (e.g., 404a) are connected in parallel. In this arrangement, as shown in FIGS. 6A (top view) -6B (bottom view), at least six different types of busbars (e.g., 416a, 417a-417b, 418a, 419a-419b, 420a, 421a) are required to connect the cells in groups of 11 in parallel with 14 series connections.

[0045] As such, both the direct arrangement and the tangent arrangement require at least six different types of busbars in order to connect the cells such that groups of cells are connected in parallel with the groups connected in series. Using six different types of busbars increases the complexity and cost of design and manufacturing of the battery module, e.g., the design and assembly are more difficult and the costs associated with molds are higher.

[0046] A battery module arrangement according to the present disclosure, in contrast, requires fewer types of busbars than conventional direct and tangent arrangements by forming a basic unit of battery cells having a number of cells that equals a prime number value and arranging those cells and basic units in a manner described below. In a preferred embodiment, the battery cells are cylindrical batteries and the prime number is greater than 7, preferably greater than 9, and up to 199.

[0047] A basic unit of battery cells may be considered as a building block of the battery module comprising a prime number of cells to be connected in parallel with one another. Each basic unit has three rows of cells in a tangent arrangement, where the number of cells in the inner row and each of the outer rows is determined based on a breakdown of the prime number, and in which each cell of each outer row is in tangent arrangement with two cells of the inner row. In the example shown inFIG. 7, the prime number is 11 for basic unit 501a and the outer rows 502 (502a, 502b) have four cells 504 (504a-504d and 504h-504k) each and the inner row 506a has three cells 504 (504e-504g). Each unit that has the same number of cells will have the same arrangement, as can be seen in FIG. 8, in which another basic unit 501b has four cells (5041-504o) in outer row 502c, four cells in outer row 502d, and three cells in inner row 506b. (As used herein, “row” may be a line of cells vertically (as depicted in the figures) or horizontally, and it will be understood that such descriptions are for explaining the arrangements and not limiting in terms of spatial orientation.)

[0048] The basic units 501 are then grouped with other basic units to form modules, e.g., module 500 as shown in FIG. 9. For example, to create an 11 parallel, 14 series module, these basic units 501 with 11 cells connected in parallel may be arranged with outer cells of adjacent units in a direct arrangement alignment. This may be done in any suitable manner, including having two rows of equal numbers of subunits aligned next to each other, as shown in FIG. 9. For example, as shown in FIG. 7, cells 504h-504k of outer row 502b of unit 501a are in direct arrangement alignment with cells 5041-504o of outer row 502c of unit 501b (FIG. 8).

[0049] In these arrangements, fewer types of busbars are required to connect the cells due to the spatial relationship of the cells and cell terminals in each basic unit, as well as the spatial arrangement of the basic units. As can be seen in FIGS. 10A-10B, only three types of busbars are required to connect the cells in this arrangement for the 11 parallel, 14 series module of this example. To connect the 14 basic units (i.e., 501a-501n), only twelve of a first type of busbar 522 (522a-5221), two of a second type of busbar 523 (523a-523b), and two of a third type of busbar 524 (524a-524b) are required to connect all the cells / units in the desired manner.

[0050] Basic units of different numbers of cells can be formed. The number of cells in the inner row and the outer rows for any basic unit is determined as follows. A prime number, N (wherein N is preferably greater than seven) is selected as the parallel number for the basic unit and the series number, S, can be an even or odd number. The total number of batteries in the module would then be N x S. These battery cells are first formed into basic units having N cells each in which the number of cells in the inner row and the outer rows is determined by breaking down the prime number N into three numbers that sum to N, where each of the numbers corresponds to the number of cells in a row.

[0051] These arrangements of basic units depend on the fact that prime numbers can be disassembled as the sum of two times a number plus an adjacent number. If N is a prime number (N > 3), then N is equal to the sum of a number and twice an adjacent number. The number of cells in each row is determined, for each selected prime number, by Equations 1 or 2, below, depending on whether the value of N / 3 (rounded down to the nearest whole number as used throughout) is odd or even. For these purposes, the value [N / 3] is rounded down to the nearest whole number throughout. Thus, the number of cells in the inner and outer rows depends on N and whether the value of [N / 3] is odd or even. The number and adjacent number used depends on whether [N / 3] is an odd or even number, and can be expressed as follows:If [N / 3] is odd, then N = [N / 3] + 2*([N / 3] + 1) (Equation 1)If [N / 3] is an even number, then N = [N / 3]+l + 2*[N / 3] (Equation 2) where N is a prime number greater than 3 and as noted the value [N / 3] is rounded down to the closest whole number.

[0052] For the basic units, if [N / 3] is odd, the inner row will have [N / 3] cells; if [N / 3] is even, the inner row will have [N / 3] + 1 cells. The outer rows will have [N / 3] + 1 cells if [N / 3] is odd and will have [N / 3] cells if [N / 3] is even. For example, the basic unit 501a shown in FIG. 7 has N = 11. Since [N / 3] is 3 and thus odd, the inner row has N / 3 (i.e., 3) cells, and the outer rows each have N / 3 + 1 (i.e., 4) cells. In another example, as shown in FIG. 11, a basic unit 601a is shown for an N value of 13, where basic unit 601a includes an inner row 606 (e.g., 606a) with five cells 604 (e.g., 604a-604e) and outer rows 602 (e.g., 602a, 602b) with four cells 604 (e.g., 604f-604i and 604j- 604m) each. As can be seen, the cells of the inner rows and outer rows of each basic unit are in tangent arrangement (e.g., 604b is in tangent arrangement with 604g).

[0053] With a series number of 12, the basic units 601 are arrayed such that cells of the outer rows 602 of adjacent basic units 601 are aligned in a direct arrangement manner, as are the outermost cells on the ends of adjacent basic units, as can be seen in module 600 in FIG. 12.

[0054] In this way, the number of different types of busbars required to connect the cells are reduced compared to the number of different types of modules with the same number of cells andconnections arrayed in direct or tangent arrangements. In addition, compared with a direct arrangement or tangent arrangement, the grouped cells have a smaller aspect ratio, which is advantageous for certain space cell arrangements (e.g., arrangements that are not long and narrow).

[0055] For example, for an 1 IP, 14S battery arranged in a direct arrangement, a regular tangent arrangement, and an arrangement disclosed herein (as shown in the example in FIG. 9), the arrangement disclosed herein requires fewer types of busbars and results in a smaller length to width ratio, as summarized in Table 1 below.Table 1

[0056] It will be understood that similar arrangements may be made with prismatic cells as well, except that instead of a tangent arrangement of rows of cells, an offset arrangement is used wherein the offset is preferably one-half of the dimension of the cells in the row direction. In addition, although the arrangements described herein have been based on basic units having a prime number of cells, basic units having a non-prime number of cells may be possible.

[0057] Various modifications and additions can be made without departing from the spirit and scope of this disclosure. Features of each of the various embodiments described above may be combined with features of other described embodiments as appropriate in order to provide a multiplicity of feature combinations in associated new embodiments. Furthermore, while the foregoing describes a number of separate embodiments, what has been described herein is merely illustrative of the application of the principles of the present disclosure. Additionally, although particular methods herein may be illustrated and / or described as being performed in a specific order,the ordering is highly variable within ordinary skill to achieve aspects of the present disclosure. Accordingly, this description is meant to be taken only by way of example, and not to otherwise limit the scope of this disclosure.

[0058] Exemplary embodiments have been disclosed above and illustrated in the accompanying drawings. It will be understood by those skilled in the art that various changes, omissions and additions may be made to that which is specifically disclosed herein without departing from the spirit and scope of the present disclosure.

Claims

What is claimed is:

1. A battery module comprising: a plurality of cylindrical battery cells; and a plurality of basic units, each of the plurality of basic units including N of the plurality of cylindrical battery cells connected in parallel and in a tangent arrangement, wherein each of the plurality of basic units includes a first outer row, a second outer row, and a middle row between the first outer row and the second outer row, wherein N is a prime number greater than 7, wherein the first and second outer row each include N / 3 +1 battery cells if N / 3 is odd and N / 3 battery cells if N / 3 is even, where N / 3 is rounded down to a nearest whole number, wherein the middle row has N / 3 battery cells if N / 3 is odd and N / 3 + 1 battery cells if N / 3 is even, where N / 3 is rounded down to a nearest whole number, and wherein the plurality of basic units are arranged such that each cell of an outer row of a basic unit is in a direct arrangement with each cell of an outer row of an adjacent basic unit facing the outer row.

2. The battery module of claim 1 , wherein the plurality of cylindrical battery cells are connected with no more than three types of busbars.

3. The battery module of claim 2, wherein N is 11.

4. The battery module of claim 3, wherein there are 14 basic units connected in series.

5. The battery module of claim 2, wherein each of the plurality of basic units is arranged such that the middle row does not extend beyond an end of the first outer row or the second outer row by more than a diameter of one of the battery cells and such that neither the first outer row nor the second outer row extends beyond the middle row by more than the diameter of one of the battery cells.

6. The battery module of claim 2, wherein the middle row has m cells and the first outer row and the second outer row each have m +1 cells.

7. The battery module of claim 2, wherein the middle row has m + 1 cells and the first outer row and the second outer row each have m cells.

8. The batery module of claim 2, wherein a space utilization ratio of the battery module in a width direction is 178.5 / 190.

9. The batery module of claim 2, wherein each cell of each outer row is in tangent arrangement with two cells of the middle row.

10. A method of arranging batery cells to form a battery module, comprising: arranging a plurality of cylindrical batery cells into a plurality of basic units, wherein each of the plurality of basic units includes N cells connected in parallel and in a tangent arrangement, wherein N is a prime number greater than 7, wherein each of the plurality of basic units includes a first outer row, a second outer row, and a middle row between the first outer row and the second outer row, wherein the first and second outer row each include N / 3 +1 batery cells if N / 3 is odd and N / 3 battery cells if N / 3 is even, where N / 3 is rounded down to a nearest whole number, and wherein the middle row has N / 3 battery cells if N / 3 is odd and N / 3 + 1 batery cells if N / 3 is even, where N / 3 is rounded down to a nearest whole number; arraying the plurality of basic units such that each cell of an outer row of a basic unit is in a direct arrangement with each cell of an outer row of an adjacent basic unit facing the outer row; and connecting the plurality of cylindrical battery cells with not more than three different types of busbars.

11. The method of claim 10, further including arraying the plurality of basic units such that endmost cells of basic units are in direct arrangement with respective endmost cells of adjacent basic units facing the endmost cells.

12. The method of claim 10, further including connecting the N cells of each of the plurality of basic units in parallel and connecting the plurality of basic units in series.

13. A method of arranging batery cells in a battery module, comprising: selecting a number, N, of cells to group into each of a plurality of basic units, wherein N is a prime number greater than 7; arranging, for each of the plurality of basic units, N cells into three subgroups of cells, including a first outside subgroup and a second outside subgroup, each having N / 3 +1 cells aligned ifN / 3 is odd and N / 3 cells aligned if N / 3 is even, and a middle subgroup having N / 3 cells aligned if N / 3 is odd and N / 3 + 1 cells aligned if N / 3 is even, where N / 3 is rounded down to a nearest whole number; connecting the N cells of each of the plurality of basic units in parallel; and connecting the plurality of basic units in series.

14. The method of claim 13, wherein the connecting includes not more than three different types of busbars.

15. The method of claim 13, wherein each cell of the first outside and the second outside subgroup of each basic unit is in tangent arrangement with two cells of the middle subgroup.

16. The method of claim 15, further including arraying the plurality of basic units such that each cell of an outer row of a basic unit is in a direct arrangement with each cell of an outer row of an adjacent basic unit facing the outer row.

17. The method of claim 16, further including arraying the plurality of basic units such that endmost cells of basic units are in direct arrangement with respective endmost cells of adjacent basic units facing the endmost cells.

18. A battery module comprising: a plurality of battery cells; and a plurality of basic units, each of the plurality of basic units including N of the plurality of battery cells connected in parallel, wherein each of the plurality of basic units includes a first outer row, a second outer row, and a middle row between the first outer row and the second outer row, wherein N is a prime number greater than 7, wherein the first and second outer row each include N / 3 +1 battery cells if N / 3 is odd and N / 3 battery cells if N / 3 is even, where N / 3 is rounded down to a nearest whole number, wherein the middle row has N / 3 battery cells if N / 3 is odd and N / 3 + 1 battery cells if N / 3 is even, where N / 3 is rounded down to a nearest whole number, wherein each of the first and second outer row battery cells are in tangent arrangement with two inner row battery cells, and wherein the plurality of battery cells are connected with no more than three types of busbars.

19. The batery module of claim 18, wherein N is 11.

20. The batery module of claim 19, wherein there are 14 basic units connected in series.

21. The batery module of claim 18, wherein each of the plurality of basic units is arranged such that the middle row does not extend beyond an end of the first outer row or the second outer row by more than a diameter of one of the batery cells and such that neither the first outer row nor the second outer row extends beyond the middle row by more than the diameter of one of the batery cells.

22. The batery module of claim 18, wherein the middle row has m cells and the first and second outer rows each have m +1 cells.

23. The batery module of claim 18, wherein the middle row has m + 1 cells and the first and second outer rows each have m cells.

24. A battery module comprising: a plurality of cylindrical battery cells; and a plurality of basic units of cells formed from the plurality of cylindrical batery cells, wherein each of the plurality of basic units includes a group of N of the plurality of cylindrical batery cells connected in parallel and in a tangent arrangement, wherein each of the plurality of basic units includes a first outer row, a second outer row, and a middle row, wherein N is a prime number greater than 7, wherein the first and second outer row each include N / 3 +1 batery cells when N / 3 is odd and N / 3 battery cells when N / 3 is even, where N / 3 is rounded down to a nearest whole number, and wherein the middle row has N / 3 batery cells when N / 3 is odd and N / 3 + 1 battery cells when N / 3 is even, where N / 3 is rounded down to a nearest whole number, wherein the plurality of basic units are arranged such that outer row batery cells of facing rows of adjacent basic units are aligned in a direct arrangement manner.

25. The batery module of claim 24, wherein the plurality of basic units are arranged such that one or more corresponding batery cells at ends of rows of adjacent basic units are aligned in a direct arrangement manner.

26. The batery module of claim 25, wherein the plurality of cylindrical battery cells are connected with no more than three types of busbars.

27. The batery module of claim 25, wherein N is 11.

28. The batery module of claim 27, wherein there are 14 basic units connected in series.

29. The batery module of claim 28, wherein the plurality of basic units are aligned in two groups of 7.

30. The batery module of claim 26, wherein each of the plurality of basic units is arranged such that the middle row does not extend beyond an end of the first outer row or the second outer row by more than a diameter of one of the battery cells and such that neither the first outer row nor the second outer row extends beyond the middle row by more than the diameter of one of the batery cells.

31. The batery module of claim 26, wherein there are S basic units connected in series.

32. The batery module of claim 31, wherein the plurality of basic units are aligned in two groups of S / 2.

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