Patent Application
20240380031
This nonprovisional application claims priority under 35 U.S.C. § 119(a) to German Patent Application No. 10 2023 204 259.2, which was filed in Germany on May 9, 2023, and which is herein incorporated by reference.
The invention relates to a battery cell.
A generic battery cell includes a completely rigid cell housing, which has a housing base part and a housing cover, which is rigidly connected to the housing base part. The housing base part and the housing cover limit an electrode receiving chamber, in which an electrode stack is arranged. The electrode stack changes its thickness, depending on the state of charge of the battery cell. The rigid cell housing is repeatedly mechanically stressed, i.e., with each charge cycle, due to the change in thickness. The rigid cell housing may withstand this mechanical stress only for a limited number of charge cycles until the cell housing undergoes structural failure.
US 2019/0173065 A1 discloses a hybrid battery cell module. A prismatic battery cell including a pouch battery cell is known from KR 10-1546661 B1. KR 10-0795781 B1 discloses a secondary battery cell and a method for its manufacture.
It is therefore an object of the invention to provide a battery cell, whose cell housing is subjected to less mechanical stress with a change in the thickness of the electrode arrangement.
According to an example of the invention, a battery cell is proposed, which includes a cell housing and at least one electrode arrangement, the cell housing including a housing base part and a housing cover, and the housing base part, together with the housing cover, limiting an electrode receiving chamber, in which the electrode arrangement is arranged. According to the invention, the housing cover is movably connected to the housing base part via a preferably flexible and/or elastic and/or permanently elastic sealing element. Due to the flexible connection of the housing cover to the housing base part, the cell housing is subjected to much less mechanical stress—with the same change in thickness of the electrode arrangement—than is the case of the cell housing described at the outset. The cell hosing may therefore withstand many more charge cycles without damage.
The aspects mentioned below primarily relate to the battery cell according to the first example, and the aspects mentioned below may also relate to a battery cell according to further examples.
The housing base part can be trough-shaped and/or dimensionally stable.
The housing base part can include a housing base as well as, preferably exactly four housing side walls.
The housing side walls can each be connected to the housing base and/or are connected to the housing base in a materially uniform manner and/or as a single piece.
Each housing side wall can have a side wall end face.
For example, the housing cover can be designed to be essentially plate-shaped and/or dimensionally stable and/or rigid, and/or the housing base is designed to be essentially plate-shaped and/or dimensionally stable and/or rigid. The use of a rigid plate-shaped housing cover has the advantage that a homogeneous pressure may be easily applied to the electrode arrangement via the housing cover.
The cell housing can be formed by an essentially prismatic, preferably cube-shaped, cell housing.
The housing base part and/or the cell housing can be rotationally symmetrical with respect to a rotational symmetry axis of the cell housing.
The sealing element can be formed by a sealing strip or by a cured and/or cross-linked and/or permanently elastic sealing material. The sealing material particularly preferably has the advantage that manufacturing tolerances between the housing base part and the housing cover may be easily compensated for. In the case of minor thickness changes, in particular, the permanently elastic sealing material may be particularly advantageously used. In the case of greater thickness changes, the sealing strip has advantages compared to the sealing material.
For example, the sealing element or the sealing strip or the cured and/or cross-linked and/or permanently elastic sealing material may each have the shape of a closed ring.
The electrode arrangement can be in direct contact connection with a cover surface of the housing cover on the inside of the housing and/or with the housing base, preferably in each state of charge of the electrode arrangement.
The housing cover can extend in parallel to the housing base, preferably in each state of charge of the electrode arrangement.
An annular gap, which runs in the circumferential direction with respect to a rotational symmetry axis of the housing base part or with respect to a rotational symmetry axis of the cell housing, can extend between the housing cover and the housing side walls of the housing base part. It may preferably be provided that the sealing element is arranged in the annular gap and extends along the entire annular gap, preferably without interruption. The annular gap has the advantage that no narrow manufacturing tolerances need to be maintained between the housing cover and the housing base part.
The sealing element can be connected to the cover surface of the housing cover on the inside of the housing and/or to the narrow end surfaces of the housing cover.
The sealing element can be partially or completed connected to inner surfaces of the housing side walls and/or to the side wall end faces of the housing side walls.
The sealing element can seal the electrode receiving chamber to the outside, preferably gas-tight, preferably in the region of the annular gap. The electrode receiving chamber is thus reliably sealed against the penetration of, for example, moisture or dirt.
The housing cover may at least partially projects over the housing base part when the electrode arrangement is approximately fully charged or fully charged. Further, it may be provided that the housing cover can close upwardly flush with the side wall end faces of the housing base part when the electrode arrangement is approximately fully charged or fully charged. The housing cover can extend completely on the side of an end face plane facing the housing base when the electrode arrangement is approximately fully charged or fully charged. For example, the side wall end faces can extend in the end face plane, for example, outside of recesses.
The sealing element can bulge and/or press outwardly over the housing base part, preferably radially to the outside, preferably with respect to a rotational symmetry axis of the housing base part and/or to the greatest extent, and/or the housing cover can extend completely on the side of an end face plane facing the housing base when the electrode arrangement is approximately fully discharged or fully discharged, and/or the sealing element can be connected to the housing base part and the housing cover in such a way that the sealing element is in a stretched state, preferably in the direction of the housing base, when the electrode arrangement is at least approximately discharged. Due to the fact that the sealing element bulges and/or presses radially to the outside, the displacement of the sealing element into the electrode receiving chamber may be prevented. A mechanical damage of the electrode stack by the sealing element may be prevented thereby.
Also, in the region of the side wall end faces, the housing side walls may limit groove-shaped and/or cuboid recesses, into which the sealing element may be displaced, preferably when the electrode arrangement is approximately fully charged or fully charged. The sealing element may thus not only press or bulge radially to the outside, but also simultaneously be displaced into the region of the recesses. This ensures with a particularly high degree of certainty that the electrode stack may not be damaged by the sealing element.
The sealing element can be connected to the housing base part and the housing cover in such a way that the sealing element is in an unstretched and/or compressed state when the electrode arrangement is approximately fully charged or fully charged.
The battery cell can changes its thickness when the state of charge of the electrode arrangement changes. This may also be referred to as “breathing.”
A housing base part depth of the housing base part and/or the electrode stack is dimensioned in such a way that the housing cover projects over the housing base part by a projection when the battery cell is approximately fully charged or fully charged, and/or the housing cover does not project out of the housing base part when the battery cell is approximately fully charged or fully charged. The recesses may be optionally provided in both cases.
According to the invention, an arrangement is proposed, which includes a first battery cell according to the first example and a second battery cell according to the first example, the housing base of the first battery cell and the housing base of the second battery cell being arranged congruently to each other, and the housing base of the first battery cell and the housing base of the second battery cell being connected to each other, preferably in a materially uniform manner and/or as a single piece and/or over a wide area. Two battery cells may thus be easily combined with each other in a space-saving manner.
It may be provided, for example, that the housing cover, the cover surface has the cover surface on the inside of the housing, a cover surface on the outside of the housing, and preferably exactly four narrow side surfaces.
According to the invention, a battery cell is proposed, which includes a cell housing and at least one electrode arrangement, preferably as described above, the cell housing including a housing base part, preferably as described above, as well as a housing cover, and the housing base part, together with the housing cover, limiting an electrode receiving chamber, for example, as described above, in which the electrode arrangement is arranged. According to the invention, the housing cover is formed by a preferably non-rigid and/or flexible and/or pouch foil-like foil. Due to the fact that the housing cover is provided with a non-rigid and/or flexible design, the mechanical stresses occurring during the charge cycles are absorbed by the expansion of the foil. A structural failure of the cell housing may thus be avoided.
It may be provided, for example, that the material of the housing base part can be entirely or partially plastic, preferably fiber-reinforced plastic, and/or the material of the housing base part can be entirely or partially metal, and/or the material of the housing base part includes metal and preferably fiber-reinforced plastic.
It may be provided by way of example that the housing base part can include a housing base and preferably exactly four housing side walls, each having an outer surface, and the foil is fastened directly or indirectly with an intermediate layer of a plastic coating to one, two, three, or all outer surfaces of the housing side walls, preferably glued or sealed to one, two, three, or all outer surfaces of the housing side walls.
According to the invention, an arrangement can be provided, which includes a first battery cell according to the second example and a second battery cell according to the second example, the housing base of the first battery cell and the housing base of the second battery cell being arranged congruently to each other, and the housing base of the first battery cell and the housing base of the second battery cell being connected to each other, preferably in a materially uniform manner and/or as a single piece and/or over a wide area. Two battery cells may thus be easily combined with each other in a space-saving manner.
The foil of the first battery cell and the foil of the second battery cell can be connected in a materially uniform manner and/or as a single piece.
The foil of the first battery cell and the foil of the second battery cell can be fastened to one and the same outer surface of one of the housing side walls and/or are glued to one and the same outer surface of one of the housing side walls.
The housing base of the first battery cell and the housing base of the second battery cells can each project over the housing side walls radially to the outside, preferably in an annular manner, preferably with respect to a rotational symmetry axis of the cell housing, forming an annular projection, and the annular projection is not covered by the foil(s) and/or not by the plastic coating.
The aspects mentioned below also relate to the battery cell according to the first example as well as to the battery cell according to the second example.
It may be provided, for example, that the electrode arrangement can include at least two preferably plate-shaped or cuboid electrodes and one preferably plate-shaped separator.
It may be provided by way of example that the electrodes and the separator can be stacked one on top of the other along the rotational symmetry axis of the cell housing, it preferably being able to be provided that the separator is arranged between the electrodes, and/or the electrodes are separated by the separator, preferably electrically and/or electrochemically.
An electrode arrangement which is formed by multiple electrodes stacked one on top of the other along the rotational symmetry axis of the cell housing may be referred to as an electrode stack.
The electrodes and the separator can be wound around a common winding axis, it being preferably able to be provided that the two electrodes are separated by the separator, preferably electrically and/or electrochemically.
The housing base part and/or the cell housing can be rotationally symmetrical, preferably in a two-fold or four-fold manner, with respect to the rotational symmetry axis of the cell housing, it preferably being able to be provided that the rotational symmetry axis extends orthogonally to the housing base.
The housing base part can be a component manufactured in a materially uniform and/or one-piece and/or integral manner. It may alternatively be provided that the housing base is joined to the housing side walls.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes, combinations, and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:
A battery cell 1 according to a first example is shown in
An annular gap 15 having an annular gap width b extends between housing cover 13 and housing side walls 11. A sealing element 17 formed by a cured and/or cross-linked and/or permanently elastic sealing material extends in annular gap 15, with the aid of which housing cover 13 is flexibly and/or movable connected to housing base part 7 in such a way that housing cover 13 is essentially displaceable in parallel to housing base 9.
Housing base part 7, housing cover 13, and sealing element 17 together limit an electrode receiving chamber 19, in which electrode arrangement 5 is arranged. Electrode arrangement 5 is formed by electrodes 21 and separators 23, one of separators 23 being arranged in each case between two adjacent electrodes 21. Housing base part 7 and the cell housing are each rotationally symmetrical, preferably in a two-fold or four-fold manner, with respect to a rotational symmetry axis A.
Sealing element 17 is connected to housing side walls 11 in the region of side wall end faces 25 of housing side walls 11. Sealing element 17 is additionally connected to a cover surface 27 of housing cover 13 on the inside of the housing and to narrow side surfaces 29 of housing cover 13.
Sealing element 17 seals electrode receiving chamber 19 gas-tight to the outside and, due to the flexible connection of housing cover 13 to housing base part 7, permits a height of electrode receiving chamber 19 to be adapted to a stack thickness of electrode arrangement 5, which increases as the state of charge of electrode arrangement 5 increases. Electrode arrangement 5 has its maximum stack thickness d1 when the battery cell is fully charged. At the same time, electrode receiving chamber 19 has its maximum height. This state of charge is illustrated, for example, in
A housing base part depth t (cf.
A side view of housing side walls 11 is illustrated in
An arrangement 35 is illustrated in
A battery cell 41 according to a second example is illustrated in
Battery cell 41 includes housing base part 7 as well as electrode arrangement 5. Housing base part 7, together with a housing cover 43, limits an electrode receiving chamber 45.
In comparison to the first example, housing cover 43 in the case of this battery cell 41 is formed by a preferably non-rigid and/or flexible and/or pouch foil-like foil.
Housing base part 7 is manufactured from metal and is provided with a plastic coating 47 on outer surfaces of housing side walls 11, to which housing cover 43 formed by the foil is glued.
An arrangement 51 is illustrated in
As illustrated in
The foils of the two battery cells 41 may be connected to each other in a materially uniform manner and/or as a single piece, and they may both be glued to a plastic coating 47 applied to an outer surface of housing side walls 11.
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2023 204 259.2 | May 2023 | DE | national |
