Storage battery pack

Abstract

The invention relates to a battery pack, in particular a replaceable battery pack, comprising a housing in which at least one battery cell, a first cell holder for receiving at least one first battery cell, and a second cell holder for receiving at least one second battery cell are arranged. According to the invention, the first cell holder and the second cell holder are connected to each other in a force-fitting and / or form-fitting manner by means of at least one fastening element.

Description

TECHNICAL FIELD

[0001] The application relates to a battery pack, in particular a replaceable battery pack. BACKGROUND

[0002] A battery assembly having a plurality of battery cells is described in DE 10 2020 201 165 A1, wherein tie rods are provided for exerting a pre-tension on the battery pack. SUMMARY

[0003] The application relates to a battery pack, in particular a replaceable battery pack, having a housing in which at least one battery cell is arranged, a first cell holder for receiving at least one first battery cell and a second cell holder for receiving at least one second battery cell. It is proposed that the first cell holder and the second cell holder are connected to one another in a force- and / or form-locking manner by at least one fixing element. Advantageously, the stability of the battery pack can thereby be improved.

[0004] The battery pack is in particular part of a system consisting of the battery pack and an electric consumer, wherein the electric consumer is supplied with electrical power by the battery pack during operation. The battery pack can for example be configured as a hand-held power tool battery pack or as an e-bike battery pack. The battery pack is in particular configured as a replaceable battery pack, which is configured to be detachably connected to the electric consumer, preferably without the need for tools. Alternatively, it is also conceivable that the battery pack is fixedly installed or integrated in the housing of the electric consumer. The battery pack is in particular connectable to a charging device for charging the battery pack. Alternatively or additionally, the battery pack can also be configured such that it can be charged in the state of connection to the electric consumer.

[0005] The electric consumer is in particular configured as a garden tool, for example a lawnmower or a pruning shear, as a household appliance, for example an electric window cleaner or a hand-held vacuum cleaner, as a hand-held power tool, for example an angle grinder, a screwdriver, a drill, a drill hammer, etc., as an electric propulsion device, for example in the form of a Pedelec or an E-Bike, an electric scooter or a measuring tool, for example a laser distance meter. Furthermore, it is also conceivable that the electric consumer is configured as another, in particular portable, appliance, for example a construction site lighting device, a vacuum cleaner or a construction site radio.

[0006] The battery pack has a housing in which the battery cells are received. The housing of the battery pack is preferably configured as an outer housing. The battery pack, in particular the housing of the battery pack, can be configured to be detachably connected or fixedly connected with the electrical consumer and / or the charging device by means of a mechanical interface. The housing of the battery pack can have one or more housing components. The housing has at least one housing component which is configured as an outer housing component. Preferably, the housing consists entirely of outer housing components. The outer housing components here shield the battery pack from the outside and can be touched by the user. Furthermore, the housing can have at least one inner housing component which is completely surrounded by at least one housing component. The housing of the battery pack can consist of a metallic material and / or a plastic.

[0007] The cell holder of the battery pack is in particular configured as a housing component, preferably as an inner housing component. However, it is also conceivable that the cell holder is configured partially or entirely as an outer housing component. The housing of the battery pack can have one or more cell holders. The housing components, in particular the cell holders, are connected to one another in a force-locked, form-locked and / or material-locked manner. The cell holder preferably consists of a plastic, in particular of a hard plastic, preferably of a thermoplastic. The cell holder preferably consists of a high-temperature-resistant plastic, preferably of a fiber-reinforced plastic. Alternatively, it is also conceivable that the cell holder consists of a metallic material. The cell holder is in particular configured in one piece or integrally. Other materials, such as ceramics, are also conceivable. In the context of the present application, "integral" is in particular to be understood as a component which consists of one piece and not of a plurality of components which are connected to one another in a material-locked and / or force-locked and / or form-locked manner. Thus, an integral component consists of a single material. In the context of the present application, "in one piece" is to be understood as a plurality of components which are connected to one another in a material-locked manner, for example by means of two-component injection molding or material-locked. Thus, a component in one piece can consist of one or more materials. Alternatively, it is also conceivable that the cell holder is configured in multiple pieces, wherein the different parts are connected to one another in a force-locked and / or form-locked manner. The battery pack has a plurality of cell holders which are arranged next to one another and / or successively.

[0008] The battery pack can be connected to the electrical consumer in a force-locked and / or form-locked manner by means of a mechanical interface. Advantageously, the mechanical interface comprises at least one handling element by means of which the connection of the battery pack to the electrical consumer and / or the charging device is detachable. The handling element can be configured, for example, as a lock, a button, a lever or a key. The handling element can be arranged on the battery pack or on the electrical consumer. Furthermore, the mechanical interface can comprise a guide element for guiding the battery pack during the connection and / or a centering element for centering the battery pack during the connection.

[0009] Furthermore, the battery pack has at least one electrical interface through which the battery pack can be electrically connected to an electrical consumer and / or a charging device. Through the electrical connection, for example, the battery pack can be charged and / or discharged. Alternatively or additionally, it is also conceivable that information can be transmitted from the battery pack to the electrical consumer and vice versa through the electrical interface. The electrical interface is preferably configured as a contact interface in which the electrical connection is effected by physical contact of at least two electrically conductive components. The electrical interface preferably comprises at least two electrical contact elements. In particular, one of the electrical contact elements is configured as a positive contact and the other electrical contact element is configured as a negative contact. Additionally, the electrical interface can have at least one additional contact which is configured for transmitting additional information to the electrical consumer and / or the charging device. The additional contact can be configured as a signal contact, a coding contact, a temperature contact, a bus contact, etc. The electrical contact elements can be configured, for example, as spring contact elements in the form of contact tulips or as flat contact elements in the form of contact blades. Alternatively or additionally, the electrical interface can have a secondary charging coil element for inductive charging. The mechanical interface and the electrical interface can be configured integrally or separately from one another.

[0010] In particular, the battery pack has electronics. The electronics of the battery pack can have, for example, a circuit board, a computing unit, a control unit, transistors, capacitors, sensor elements, light-emitting diodes, memory units, etc. Additionally or alternatively, it is also conceivable that information is derived by the electronics. The electronics are in particular configured for controlling or regulating the battery pack and / or the electrical consumer. The electronics in particular comprise a BMS (English: battery management system) which is configured for monitoring the battery pack. The BMS is in particular configured for preventing overcharging and / or deep discharging of the battery pack. Preferably, the BMS is configured for correct cell symmetrization. The electronics can also have one or more sensor elements, for example a temperature sensor for deriving a temperature within the battery pack or a movement sensor for deriving a movement. Alternatively or additionally, the electronics can have a coding element, for example a coding resistor. The electrical contact elements of the electrical interface of the battery pack can be arranged on or connected to a circuit board of the electronics. In the context of the present application, a "circuit board" is to be understood as a circuit carrier having an organic or inorganic substrate, for example an IMS. The circuit board can be configured as a rigid circuit board or a flexible circuit board. Furthermore, the circuit board can be a populated or an unpopulated circuit board. The circuit board can be configured with a single layer or with multiple layers.

[0011] The battery cells can be configured as primary cells, which have a structure in which one battery pole is located at one end and the other battery pole is located at the opposite end. In particular, the battery cells have a positive battery pole at one end and a negative battery pole at the opposite end. Preferably, the battery cells are configured as NiCd or NiMh battery cells, particularly preferably as lithium-based battery cells or lithium-ion battery cells. Alternatively, it is also conceivable, for example, that the battery cells are configured as soft-pack battery cells or prismatic battery cells. The battery voltage of the battery pack is generally a multiple of the individual battery cell voltage and results from the manner in which the battery cells are connected (in parallel or in series). For battery cells of the common voltage of 3.6 V, exemplary battery voltages of 3.6 V, 7.2 V, 10.8 V, 14.4 V, 18 V, 36 V, 54 V, 108 V, etc. thus result. Preferably, the battery cells are configured as at least substantially cylindrical round cells, wherein the battery poles are arranged on the end of the cylindrical shape.

[0012] The securing element is preferably configured as a separate component which is connected to the cell holder during assembly. The securing element is preferably configured in one piece or in one piece. The securing element is preferably composed of a different material than the cell holder. It is particularly conceivable that the securing element is composed of a material which is more elastic than the cell holder. The connection of the securing element is at least partially or completely carried out directly, such that the securing element is directly applied against the cell holder to be connected. The force-locked connection is preferably achieved here by a press fit.

[0013] In the context of the present application, the first cell holder and the second cell holder are particularly to be understood as different cell holders which are arranged next to one another.

[0014] It is furthermore proposed that the first cell holder and the second cell holder are configured substantially identically. In particular, the cell holders are configured for receiving the same number and / or type of battery cells.

[0015] It is furthermore proposed that the securing element is configured for force-locked securing of the battery cells in the cell holder. Advantageously, the stability of the battery pack can thereby be further improved.

[0016] It is furthermore proposed that the cell holder has at least one wall for each battery cell, which delimits a receiving space for the respective battery cell. The wall is particularly configured such that the battery cell lies against the wall in an area-like or line-like manner. Preferably, the securing element lies against the wall such that a radial force is exerted onto the battery cell by the wall. In particular, the securing element is configured such that the securing element regionally deforms the wall.

[0017] It is further proposed that the first cell holder has at least one first fixing element receptacle and the second cell holder has at least one second fixing element receptacle, which are arranged in alignment. Advantageously, a compact design can thereby be achieved. The fixing element receptacles can be arranged close to one another or spaced apart from one another.

[0018] It is further proposed that the fixing element is configured rod-like and is arranged in the first fixing element receptacle and in the second fixing element receptacle in the connected state. Advantageously, an effective fixing can thereby be achieved. Preferably, the fixing element loads the first battery cell and the second battery cell in the fixing element receptacle with a radial force, such that the first cell holder is connected with the second cell holder.

[0019] It is further proposed that the battery pack has a further fastening device, which is configured for fastening the cell holders to one another. Advantageously, the stability of the battery pack can thereby be further improved. The fastening device is configured in particular separately from the fixing element. The fastening device is preferably configured for axially pressing the cell holders. The fastening element can be configured for example as a tension rod.

[0020] It is further proposed that the fixing element is configured as a curved rod. Advantageously, the assembly can thereby be optimized.

[0021] It is further proposed that the fixing element consists of plastic, in particular of polyamide. It is alternatively also conceivable that the fixing element consists of carbon fiber or a similar material. It is alternatively or additionally also conceivable that the fixing element consists of metal, in particular of aluminum or steel.

[0022] It is further proposed that the fixing element consists of a thermally conductive material. Advantageously, the heat dissipation in the battery pack can thereby be optimized.

[0023] It is further proposed that the fixing element is formed on the first cell holder and has a length of at least 50%, preferably at least 75%, of the length of the adjacent second cell holder. In particular, the fixing element is configured integrally or in one piece with the first cell holder or the second cell holder. BRIEF DESCRIPTION OF DRAWINGS

[0024] Further advantages emerge from the following description of the drawings. In the drawings, embodiments of the application are shown. The drawings, the description and the claims contain a plurality of features in combination. The person skilled in the art can also consider the features individually in accordance with the object and summarize them into further, meaningful combinations.

[0025] The drawings show:

[0026] Figure 1 : perspective view of an electric bicycle with a battery pack;

[0027] Figure 2 perspective view of an exemplary battery pack;

[0028] Figure 3 perspective view of a single cell holder with at least one fixing element;

[0029] Figure 4 front view of a single cell holder according to Figure 3

[0030] Figure 5 schematic side view of a plurality of single cell holders interconnected by fixing elements and fastening means. DETAILED DESCRIPTION

[0031] In Figure 1 a perspective side view, an electrical consumer 10 with a battery pack 100 is shown. The electrical consumer 10 is configured, for example, as an electrically driven forward movement device 12, in particular as an electric bicycle 14. The electric bicycle 14 can be configured, for example, as a Pedelec or an E-Bike.

[0032] The electric bicycle 14 has a frame 18 or a bicycle frame. Two wheels 20 are connected to the frame 18. Furthermore, the electrical consumer 10 has a drive unit 22, which comprises an electric motor. The electric motor is preferably configured as a brushless direct-current electric motor with permanent magnet excitation. The electric motor is configured, for example, as a mid-motor, it being possible for a hub motor or a similar motor to also be considered.

[0033] The drive unit 22 comprises a control unit (not shown), which is configured for controlling or regulating the electric bicycle 14, in particular the electric motor. The electric bicycle 14 has a pedal crank 24. The pedal crank 24 is connected to a pedal crank shaft (not shown).

[0034] The control unit and the drive unit 22 with the electric motor and the pedal crank shaft are arranged in a drive housing 26, which is connected to the frame. The drive movement of the electric motor is preferably transmitted to the pedal crank shaft by means of a transmission (not shown), wherein the degree of assistance by the drive unit 22 is controlled or regulated by means of the control unit.

[0035] The electrical consumer 10 is electrically and mechanically connected to a battery pack 100, which is configured for supplying the drive unit 22 with electrical power. The battery pack 100 is configured, for example, as a replaceable battery pack 102. The battery pack 100 is received, for example, in the connected state completely in the frame 18 of the electric bicycle 14. The connection can be achieved here by pushing the battery pack 100 axially into a lower tube of the frame 18 or by pivoting the battery pack 100 into the frame 18 from the side. It is alternatively also possible for the battery pack 100 to be configured in such a way that the battery pack 100 can be fastened on the outside of the frame 18, for example on a lower tube or seat tube of the frame 18. ​

[0036] In Figure 2 A perspective view of the battery pack 100 is shown in Fig. 1. The battery pack 100 has a housing 104 which is configured as an outer housing. The housing 104 has, for example, a base body 105 which extends between two end plates 103, wherein the end plates 103 close the base body 105 at the end sides. The base body 105 has, for example, a rectangular cross section and extends essentially over the entire length of the battery pack 100. The base body 105 is composed, for example, of a metallic material, for example of aluminum. The end plates 103 of the housing 104 are composed, for example, of a plastic, in particular a hard plastic.

[0037] The battery pack 100 has a charge status display 106 which is arranged on the housing 104 of the battery pack 100 and is configured for displaying the charge status of the battery pack 100. Furthermore, the housing 104 of the battery pack 100 is connected with two connection plates 108. The connection plates 108 are connected, for example, with the housing 104 of the battery pack 100 by means of a screw connection, however it is also conceivable that the connection plates 108 are connected with the housing 104 by means of another connection or are configured integrally with the housing 104 of the battery pack 100. The first connection plate 110 comprises here a locking unit 113 which can be connected with a corresponding locking unit (not shown) of the e-bike 14. The second connection plate 112 comprises an electrical interface (not shown) for electrically connecting the battery pack 100 with the e-bike 14. It is also conceivable that the connection plates 108 and the end plates 103 are configured integrally or in one piece with one another.

[0038] In Figure 3 A partial perspective view of a cell holder 200 of the battery pack 100 is shown in Fig. 2. The battery pack 100 has at least two, for example four, cell holders 200 which are configured for receiving battery cells 202 of the battery pack 100. The battery cells 202 are configured, for example, as cylindrical round cells. The cell holders 200 of the battery pack 100 are configured essentially identically. The cell holders 200 are configured, for example, each for receiving ten battery cells 202, wherein, for example, only three battery cells 202 are shown.

[0039] Here, the battery cells 202 are received, for example, in individual cell receptacles 204 of the cell holder 200, such that the battery cells 202 are arranged individually and separated from one another in the cell holder 200. The individual cell receptacles 204 have a wall 205 which delimits the individual cell receptacle 204. The shape of the wall 205 is adapted here to the shape of the battery cell 202, for example, cylindrical.

[0040] The cell holder 200 is, for example, configured in multiple pieces and has a first cell holder part 206 and a second cell holder part 208. The cell holder parts 206, 208 are, for example, configured as cell holder housing halves, wherein it is also conceivable that three or more cell holder parts constitute the cell holder 200. The cell holder parts 206, 208 are, for example, plugged into one another and fastened to one another in a form-locked manner in at least one direction. It is, however, also conceivable that the cell holder parts 206, 208 are clipped to one another or are screwed to one another. It is alternatively also conceivable that the cell holder 200 is configured in one piece or integrally.

[0041] The individual cell receptacles 204 have, for example, two openings 210 each, wherein the battery cells 202 are configured to be pushed into the individual cell receptacles 204 through at least one opening 210. In the assembled state, the openings 210 are closed by means of an intermediate plate 212 arranged at the end side of the cell holder 200.

[0042] The cell holder 200 is connected to one another in a force-locked and form-locked manner by means of fixing elements 214. The fixing elements 214 are, for example, configured as rods, in particular as curved rods 216. The fixing elements 214 are, for example, composed of plastic, in particular of an elastic plastic. Preferably, the fixing elements 214 are composed of a plastic that conducts heat. It is, however, also conceivable to be made of metal, in particular steel or copper, or a pairing of different materials. The fixing elements 214 are configured as separate components, which are connected to the cell holder 200 in the assembly process. The connection is, for example, achieved here by inserting the fixing elements 214 into fixing element receptacles 218 of the cell holder 200.

[0043] The cell holder 200 has, for example, six fixing element receptacles 218. The fixing element receptacles 218 are formed by the cell holder 200. The fixing element receptacles 218 are, for example, arranged in the two cell holder parts 206, 208. The fixing element receptacles 218 are essentially identically configured and, for example, have a triangular cross section, wherein other cross sections, for example quadrangular or circular, are also conceivable.

[0044] In Figure 4 A cross section of the battery pack 100, in particular of the cell holder 200, is shown in Fig. 6. In the assembled state, the fixing elements 214 essentially completely fill the fixing element receptacles 218.

[0045] In a cross section perpendicular to the longitudinal extension of the battery pack 100, in particular of the cell holder 200, two of the six fixing element receptacles 218 are arranged centrally, while four of the six fixing element receptacles 218 are arranged at the edge side.

[0046] The fixing element receptacle 218 is here, for example, configured such that the wall 205 of the individual cell receptacle 204 also delimits the fixing element receptacle 218. Thus, in the region 220 on one side of the wall 205, the individual cell receptacle 204 is arranged, and on the other side, the fixing element receptacle 218.

[0047] In the region 220, the wall 205 can be configured such that the fixing element 214 exerts a force on the wall 205 in the direction towards the battery cell 202 arranged in the individual cell receptacle 204, wherein the wall 205 is deformed in the region 220 such that the battery cell 202 is loaded with a force radially and is thereby fixed in the individual cell receptacle 204. This can be achieved, for example, by an elastic material of the wall 205, a smaller material thickness of the wall 205 in the region 220 or by other suitable measures known to the person skilled in the art. Thus, the fixing element 214 and the fixing element receptacle 218 can be configured such that by inserting the fixing element 214 the fixing element receptacle 218 is opened, thereby activating a retaining spring which presses radially onto the battery cell 202. Advantageously, the battery cell 202 is thereby also held in its position under dynamic and impact loads.

[0048] In Figure 5 A schematic side view of five cell holders 200 in a state of mutual connection is shown in

[0049] For the assembly, the cell holders 200 are, for example, in a first step, connected to one another by the fixing elements 214. In a second step, the cell holders 200 are additionally connected by the fastening elements 222, in particular pressed against one another axially. The fastening elements 222 can be configured as tension rods, in particular as described in DE 10 2020 201 165 A1. The fastening elements 222 here extend essentially over the entire cell holder and load the intermediate plate 224 of the end side of the cell holder 200 with a force, so that the cell holders 200 are pressed against one another by the intermediate plate 224 of the end side. The fastening elements 222 are here guided by the fastening element receptacles 226 of the cell holders 200, wherein the fastening elements 222 are preferably arranged spaced apart from the cell holders 200 and in particular do not contact the cell holders 220. This can disadvantageously result in that a force acting radially onto one of the cell holders 200 can cause a lateral relative movement or tilting of one of the cell holders 200.

[0050] The fixing elements 214 are, for example, also configured to extend essentially along the length of the battery pack 100, in particular at least along the length of the cell holders 200. Thus, the fixing elements 214 connect all cell holders 200 to one another.

[0051] Since, unlike the fastening elements 222, the securing elements 214, in the state in which they are received in the securing element receptacles 218, rest on the cell holders 200, in particular substantially fill the securing element receptacles 218, stability is advantageously increased when a radial force is exerted on the cell holders 200 and lateral relative movement of the cell holders 200 relative to one another is prevented. By means of the securing elements 214, the cell holders 200 as a whole are reinforced, wherein a higher resonance frequency is advantageously produced and the robustness with respect to vibration loads is thereby increased.

Claims

1. A battery pack, in particular a replaceable battery pack, having: a housing (104) in which at least one battery cell (202) is arranged, a first cell holder (200) for receiving at least one first battery cell (202), a second cell holder (200) for receiving at least one second battery cell (202), characterized in that the first cell holder (200) and the second cell holder (200) are connected to one another in a force- and / or form-locking manner by at least one fixing element (214). The first cell holder (200) and the second cell holder (200) are identically configured. The second cell holder (200) is arranged axially behind the first cell holder (200). The cell holder (200) is composed of plastic, in particular hard plastic. The fixing element (214) is configured for force-locked fixing of the battery cell (202) in the cell holder (200). The cell holder (200) has at least one wall (205) for each battery cell (202), which delimits a receiving space (204) for the corresponding battery cell (202).

2. The battery pack of claim 1, wherein The fixing element (214) bears against the wall (205) such that a radial force is exerted onto the battery cell (202) by the wall (205).

3. Accumulator pack according to any of the preceding claims, characterized in that The first cell holder (200) has at least one first fixing element receptacle (218) and the second cell holder (200) has at least one second fixing element receptacle (218), which are arranged in alignment.

4. Accumulator pack according to any of the preceding claims, characterized in that The fixing element (214) is configured as a bar and is arranged in the first and second fixing element receptacles (218) in the connected state.

5. Accumulator group according to any of the preceding claims, characterized in that, The battery pack (200) has further fastening means (222) configured for fastening the cell holders (200) to one another.

6. Accumulator pack according to any of the preceding claims, characterized in that The fixing element (214) is configured as a bent bar (216).

7. The battery pack of claim 6, wherein The fixing element (214) is composed of plastic, in particular polyamide.

8. Accumulator pack according to any of the preceding claims, characterized in that The fixing element (214) is composed of metal, in particular aluminum or steel.

9. The battery pack of claim 8, wherein, The fixing element (214) is composed of a material that can conduct heat.

10. Accumulator group according to any one of the preceding claims, characterized in that, The fixing element (214) is formed on the first cell holder (200) and has a length that has at least 50%, preferably at least 75%, of the length of an adjacent second cell holder (200).

11. Accumulator pack according to any of the preceding claims, characterized in that ​ 12. Accumulator pack according to any of the preceding claims, characterized in that ​ 13. Accumulator pack according to any of the preceding claims, characterized in that ​ 14. Accumulator group according to any one of the preceding claims, characterized in that, ​ 15. The battery pack of any of the preceding claims, wherein, ​

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