Battery pack with sealing unit

Abstract

The invention relates to a battery pack, in particular a replaceable battery pack, having a housing, the housing having at least two housing parts, a sealing unit for sealing the housing, the sealing unit having at least one sealing element, the sealing element being received in a receiving space between the housing parts. According to the invention, the sealing element has exactly two sealing lips.

Description

Technical Field

[0001] The invention relates to a battery pack, in particular a replaceable battery pack. Background Art

[0002] DE 10 2021 206 828 A1 describes a battery pack having a lip sealing ring. Summary of the invention

[0003] The invention relates to a battery pack, in particular a replaceable battery pack, having a housing, wherein the housing has at least two housing parts, and a sealing unit for sealing the housing, wherein the sealing unit has at least one sealing element, which is received in a receiving space between the housing parts. It is proposed that the sealing element has exactly two sealing lips. Advantageously, the sealing element can ensure, in particular in the case of housing parts with thin wall thickness, that minimal or insignificant deformation of the housing parts occurs due to the sealing element and thus the surface pressure is optimized.

[0004] The battery pack is in particular a part of a system assembled from a battery pack and an electrical consumer, wherein the electrical consumer is supplied with energy during operation by the battery pack. The battery pack can be configured, for example, as a handheld machine tool battery pack or an electric bicycle battery pack. The battery pack is in particular configured as a replaceable battery pack, which is preferably detachably configured with the electrical consumer without tools. Alternatively, it is also conceivable that the battery pack is firmly mounted or integrated into the housing of the electrical consumer. Tool-free separation should also be understood as separation by a lock, such as a bicycle lock. The lock can be configured, for example, to be able to be manipulated by a key or an electric actuator. The battery pack is in particular configured to be able to be connected to a charging device for charging the battery pack. Alternatively or additionally, the battery pack can also be configured so that it can be charged in a state connected to the electrical consumer.

[0005] The electrical consumer can be designed in particular as a garden tool, such as a lawn mower or hedge trimmer, as a household appliance, such as an electric window cleaner or a handheld vacuum cleaner, as a handheld power tool, such as an angle grinder, a screwdriver, a drill, a hammer drill, etc., as an electric propulsion device, such as an electric bicycle in the form of a pedelec or an E-Bike, as an electric scooter or as a measuring tool, such as a laser distance meter. In addition, it is also conceivable that the electrical consumer is designed as another, particularly portable, appliance, such as a construction site lighting device, a vacuum cleaner or a construction site radio.

[0006] At least one battery cell is arranged in the housing of the battery pack. 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 to an electrical consumer and / or a charging device via a mechanical interface. The housing preferably has at least one housing part, which is configured as an outer housing part. The outer housing part separates the battery pack from the outside and can be touched by the user. In addition, the housing can have at least one inner housing part, which is completely surrounded by at least one housing part. The two outer housing parts are preferably connected to each other in a force-locking and / or form-locking manner. This can be achieved, for example, by a screw connection, a clamping connection or other connection types known to those skilled in the art.

[0007] The battery pack preferably has a cell holder for receiving a battery cell. The cell holder of the battery pack is particularly configured as a housing component, preferably as an inner housing component. However, it is also conceivable that the cell holder is partially or completely configured as a housing component. The housing of the battery pack can have one or more cell holders. The housing components, especially the cell holders, are connected to each other in a force-locking, form-locking and / or material-locking manner. The cell holder can also have a sleeve-shaped insert, which is in turn assigned to the protection unit and has at least one reinforcing element and / or a weakening element. The cell holder is preferably made of plastic, especially thermoplastic. The cell holder is preferably made of temperature-resistant plastic, preferably made of fiber-reinforced plastic. Alternatively, it is also conceivable that the cell holder is made of a metal material. The cell holder is particularly one-piece or integrally constructed. Other materials, such as ceramics, can also be considered. In the context of the present application, "integrated" should be particularly understood as a component composed of one piece, rather than a component composed of multiple components connected to each other in a material-locking and / or force-locking and / or form-locking manner. Therefore, an integral component is made of a single material. In the context of the present application, "one-piece" is to be understood as a plurality of components which are connected to one another in a materially bonded manner, for example by two-component injection molding or materially bonded. Thus, a one-piece component can consist of one or more materials. Alternatively, it is also conceivable that the cell holder is designed in multiple parts, wherein the different parts are connected to one another in a force-locking and / or form-locking manner. The battery pack can have one or more cell holders arranged next to one another and / or one after another.

[0008] The battery pack can be connected to the electrical load in a force-locking and / or form-locking manner via a mechanical interface. Advantageously, the mechanical interface comprises at least one operating element, via which the connection of the battery pack to the electrical load and / or the charging device is detachable. For example, the operating element can be designed as a lock, a button, a lever or a key. The operating element can be arranged on the battery pack or the electrical load. In addition, the mechanical interface can include a guide element for guiding the battery pack during the connection process and / or a centering element for centering the battery pack during the connection process.

[0009] In addition, the battery pack has at least one electrical interface, through which the battery pack can be electrically connected to an electrical load and / or a charging device. The battery pack can be charged and / or discharged, for example, via the electrical connection. Alternatively or additionally, it is also conceivable that information can be transmitted from the battery pack to the electrical load via the electrical interface, and vice versa. The electrical interface is preferably configured as a contact interface, in which the electrical connection is achieved by physical contact of at least two electrically conductive components. The electrical interface preferably includes 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 to transmit additional information to the electrical load 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 element can be configured, for example, as an elastic contact element in the form of a contact tulip or as a flat contact in the form of a contact blade. Alternatively or additionally, the electrical interface can have an auxiliary charging coil element for inductive charging. The mechanical interface and the electrical interface can be integrated or designed separately from one another.

[0010] In addition, the battery pack preferably includes an electronic device. The electronic device may, for example, have a circuit board, a computing unit, a control unit, a transistor, a capacitor and / or a storage unit. Additionally or alternatively, it is also conceivable that information is obtained by the electronic device. The electronic device is configured to control or regulate the battery pack and / or the electrical appliance. The electronic device particularly includes a BMS (battery management system), which is configured to monitor the battery pack. The BMS is particularly configured to prevent overcharging and / or deep discharge of the battery pack. Preferably, the BMS is configured for correct battery cell balancing. The electronic device may also have one or more sensor elements, such as a temperature sensor for obtaining the temperature in the battery pack or a motion sensor for obtaining movement. Alternatively or additionally, the electronic device may have a coding element, such as a coding resistor. The electrical contact elements of the electrical interface of the battery pack may be arranged on a circuit board of the electronic device or connected to the circuit board. In the context of the present application, a circuit board should be understood as a circuit carrier having an organic or inorganic substrate, such as an IMS. The circuit board may be configured as a rigid circuit board or a flexible circuit board. In addition, the circuit board may be an equipped or unequipped circuit board. The printed circuit board can have a single-layer or multi-layer design.

[0011] The battery cell can be constructed as a primary cell, which has a structure in which one cell pole is located at one end and the other cell pole is located at the opposite end. In particular, the battery cell has a positive cell pole at one end and a negative cell pole at the opposite end. The battery cell is preferably constructed as a nickel-cadmium or nickel-metal hydride battery, particularly preferably as a lithium-based battery or a lithium-ion battery. Alternatively, it is also conceivable, for example, that the battery cell is constructed as a soft-pack cell or a prismatic cell. The battery voltage of a battery pack is usually a multiple of the voltage of a single battery cell and is derived from the circuit (parallel or series) of the battery cells. Therefore, in the case of a common battery cell with a voltage of 3.6V, for example, a battery voltage of 3.6V, 7.2V, 10.8V, 14.4V, 18V, 36V, 54V, 108V, etc. is generated. Preferably, the battery cell is constructed as an at least substantially cylindrical round cell, wherein the battery cell poles are arranged at the ends of the cylindrical shape.

[0012] The sealing element is in particular made of plastic, preferably elastic plastic. The sealing element is in particular designed to be elastic in such a way that the sealing element, in particular the sealing lip, is designed to be deformed and / or compressed in the assembled state. In particular, the sealing unit has a single sealing element between each two housing parts. Preferably, the sealing element is made of rubber. The sealing element is preferably designed in one piece. In the assembled state, the sealing element is in particular arranged and pressed in the receiving space in such a way that no moisture or splashing water can enter the interior of the battery pack through the receiving space. The sealing element can be designed as a sealing ring.

[0013] The sealing lips preferably extend substantially parallel to one another. The sealing lips are arranged on a base body which extends substantially along a joining surface between the housing parts. The sealing lips preferably consist of the same material.

[0014] Furthermore, it is proposed that the sealing element is arranged radially between the first housing part and the second housing part. Advantageously, an optimized sealing effect can be ensured thereby.

[0015] Furthermore, it is proposed that the first housing part is configured as an end cap and the second housing part is configured as an especially tubular base body. Here, the end cap essentially closes the base body, especially on one side.

[0016] It is further proposed that the second sealing lip has a smaller height than the first sealing lip. Advantageously, the pressure acting on the housing via the sealing unit can be reduced thereby. The height of the second sealing lip is in particular in the region between 50% and 99% of the height of the first sealing lip, preferably in the region between 75% and 95% of the height of the first sealing lip. Preferably, the height of the second sealing lip is a few tenths of a mm smaller than the height of the first sealing lip, for example 0.2 to 0.3 mm.

[0017] It is further proposed that the second sealing lip has a smaller width than the first sealing lip. Advantageously, in particular, the pressure acting on the housing can be further optimized. The width can be the width of the respective sealing lip at the root, for example at the base of the sealing element. Alternatively, the width can also be the half-value width of the sealing lip in the middle of the respective sealing lip. In particular, the second sealing lip has a width that is reduced by at least 5%, preferably by at least 10%, advantageously by at least 25%.

[0018] Furthermore, it is proposed that the distance between the first sealing lip and the second sealing lip is smaller than the width of the first sealing lip. Advantageously, the pressure applied to the housing is further optimized thereby. In particular, the distance is designed such that the sealing lips are always spaced apart from one another in the assembled state, even if the sealing lips are bent.

[0019] Furthermore, it is proposed that the receiving space has constant dimensions in the region of the sealing element, in particular in the region of the first sealing lip. In particular, the sealing element, preferably the region of the first sealing lip, is enlarged. Advantageously, the extrusion pressure of the sealing element on the housing can thereby be optimally adjusted.

[0020] It is further proposed that the enlargement is designed in the region of 5% to 50%, preferably in the region of 10% to 20%. Advantageously, the sealing element can thereby be further optimized.

[0021] Furthermore, it is proposed that the second sealing lip varies in its dimensions. Advantageously, the sealing element can be further optimized as a result. Alternatively, it is also conceivable that the second sealing lip is designed to be constant in its dimensions.

[0022] It is further proposed that the sealing element has a connecting element for connecting the sealing element to the first housing part and / or the second housing part in a force-locking and / or form-locking manner. Advantageously, the assembly and positioning of the sealing element can be improved thereby. The housing of the battery pack preferably has at least one corresponding connecting element. The connecting element and the sealing element are preferably constructed in one piece.

[0023] Furthermore, it is proposed that the second housing part is made of a metallic material and has a thickness of less than 1.1 mm, preferably less than 0.8 mm. Advantageously, a particularly compact battery pack can thereby be provided.

[0024] Furthermore, it is proposed that the second housing part is made of plastic and has a thickness of less than 2.0 mm, preferably less than 1.5 mm. Advantageously, a particularly light battery pack can thereby be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Further advantages emerge from the following description of the drawings. The drawings, the description and the claims contain combinations of several features. A person skilled in the art will also expediently consider these features individually and combine them into further meaningful combinations.

[0026] The accompanying drawings show:

[0027] Figure 1 : A three-dimensional view of an electric bicycle having a battery pack according to the present invention;

[0028] Figure 2 : A three-dimensional view of the battery pack;

[0029] Figure 3 : Cross section of the housing component of the battery pack;

[0030] Figure 4 : Sealing components of battery packs;

[0031] Figure 5 :according to Figure 4 A top view of the sealing element of a battery pack. DETAILED DESCRIPTION

[0032] exist Figure 1 1 shows a perspective view of an electrical load 10 having a battery pack 100. The electrical load 10 is designed, for example, as an electrically driven propulsion device 12, in particular as an electric bicycle 14. The electric bicycle 14 can be designed, for example, as an electric assisted bicycle or E-Bike.

[0033] The electric bicycle 14 has a frame 18 or bicycle frame. Two wheels 20 are connected to the frame 18. In addition, the electrical load 10 has a drive unit 22, which includes an electric motor. The electric motor is preferably designed as a permanent magnet excited brushless DC motor. The electric motor is designed, for example, as a mid-mounted motor, wherein hub motors and the like are also conceivable.

[0034] The drive unit 22 comprises a control unit (not shown) which is designed to control or regulate 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 crankshaft (not shown).

[0035] The control unit and the drive unit 22 are arranged together with the electric motor and the pedal crankshaft in a drive housing 26 connected to the frame. The drive movement of the electric motor is preferably transmitted to the pedal crankshaft via a transmission (not shown), wherein the amount of assistance by the drive unit 22 is controlled or adjusted by means of the control unit.

[0036] The electrical load 10 is electrically and mechanically connected to a battery pack 100 designed to supply energy to the drive unit 22, the battery pack 100 being designed, for example, as a replaceable battery pack 102. The battery pack 100 is, for example, completely accommodated in the frame 18 of the electric bicycle 14 in the connected state. The connection can be achieved by axially inserting the battery pack 100 into the lower tube of the frame 18 or by laterally pivoting the battery pack 100 into the frame 18. Alternatively, it is conceivable that the battery pack 100 is designed in such a way that the battery pack 100 can be fixed on the outside of the frame 18.

[0037] exist Figure 2 1 shows a perspective view of the battery pack 100. The battery pack 100 has a housing 104, which is designed as an outer housing. The housing 104 of the battery pack 100 is designed, for example, so that when connected to the frame 18 of the electric bicycle 14, the frame 18 is also partially closed to the outside. This is achieved by Figure 2 The shielding element 106 is realized by a shielding element (not shown) which can be connected to the housing 104 , for example, via a longitudinal groove 105 .

[0038] The battery pack 100 has a charge state display 106, which is arranged on the housing 104 of the battery pack 100 and is designed to display the charge state of the battery pack 100. The charge state display 106 is connected to the electronic system (not shown) of the battery pack. The electronic system is arranged in the housing 104 of the battery pack 100 and includes, for example, a battery management system.

[0039] Housing 104 comprises a housing part 108 which is designed, for example, in the form of a tubular base body 110 and extends substantially over the entire length of battery pack 100 .

[0040] Furthermore, the housing 104 of the battery pack 100 has two housing parts 108, for example in the form of connecting plates 112. The connecting plates 112 are made, for example, of plastic, in particular hard plastic. The connecting plates 112 are connected, in particular screwed, for example, to the tubular base body 110 of the battery pack 100 in a force-fitting and / or form-fitting manner. The connecting plates 112 form end caps that close the base body 110 at the end.

[0041] The first connecting plate 112 comprises a locking unit (not shown) which can be connected to a corresponding locking unit (not shown) of the electric bicycle 14. The second connecting plate 112 comprises an electrical interface 114 with a socket for electrically connecting the battery pack 100 to the electric bicycle 14. In addition, the second connecting plate 112 comprises, for example, three connecting and / or centering elements 116 for connecting the battery pack 100 to the electric bicycle 14.

[0042] exist Figure 31 shows a cross section of the housing 104, in particular the base body 110. The base body 110 is constructed, for example, from a metal material, in particular aluminum. Here, the thickness of the base body 110 is in the region between 0.8 mm and 1.1 mm, for example 1.1 mm. Due to the thin wall, the rigidity of the housing 104, in particular the housing part 108 in the form of the base body 110, is reduced.

[0043] As a result of the reduced rigidity, the housing part 108 has, for example, four regions 118 which experience increased deformation in the assembled state.

[0044] exist Figure 4 1 shows a section through two housing parts 108 in the form of a base body 110 and one of the connecting plates 112. The connection of the housing parts 108 results in gaps 120 which are sealed by sealing units 122. The geometry of the housing parts 108 results in, for example, axial gaps 124 and radial gaps 126.

[0045] The sealing unit 122 has a sealing element 128, which is designed to seal the gap 120, in particular the radial gap 126. The sealing element 128 is designed, for example, as a sealing ring 130. The sealing element 128 is, for example, arranged substantially completely in a receiving space 132 of the housing 104 between the two housing parts 108. In the embodiment shown, the sealing element 128 is designed for radial sealing, wherein it is conceivable, alternatively or additionally, that the sealing element or another sealing element is designed for axial sealing.

[0046] The sealing element 128 has a substantially annular base body 134 . The base body 134 extends along the entire radial gap 126 .

[0047] Furthermore, the sealing element 128 has exactly two sealing lips 136. The sealing lips 136 extend in a particularly radial direction starting from the base body 134 of the sealing element 128. The sealing lips 136 extend continuously along the entire circumference of the sealing element 128, for example.

[0048] The first sealing lip 138 is configured as a main lip, wherein the water that penetrates from the outside through the gap 120 first loads the first sealing lip 138 or the main lip. The second sealing lip 140 is configured as an auxiliary lip, wherein the water that penetrates from the outside through the gap 120 must first be guided from the main lip before acting on the auxiliary lip. Through the subordinate arrangement of the auxiliary lip, the auxiliary lip is subjected to less stress than the main lip. Alternatively, it is also conceivable that the sealing element 128 has at least two second sealing lips 140 or at least two auxiliary lips. In the assembled state, the first sealing lip 138 is constructed in a compressed manner. For example, the second sealing lip 140 is constructed in an uncompressed manner in the assembled state, wherein it is also conceivable that the second sealing lip 140 is also constructed in a compressed manner in the assembled state. In particular, the compression of the first sealing lip 138 is greater than the compression of the second sealing lip 140.

[0049] The first sealing lip 138 has a first height 142 and a first width 143, which are different from the second height 144 and the second width 145 of the second sealing lip 140. The first height 142 of the first sealing lip 138 is, for example, approximately 10% greater than the second height 144 of the second sealing lip 140. Furthermore, the first width 143 of the first sealing lip 138 is approximately 30% greater than the second width 145 of the second sealing lip 140. These values ​​refer to the uncompressed state, wherein the height decreases due to compression and the width increases due to compression.

[0050] The receiving space 132 has, in particular, substantially the same height in the region of the sealing lips 138, 140, so that in the region of the second sealing lip 140 in the assembled state, the force exerted on the second sealing lip 140 by the housing 104 is always smaller than the force exerted on the first sealing lip 138. Figure 5 1 shows a top view of the sealing element 128. The sealing element 128, in particular the base body 134 of the sealing element 128, corresponds substantially to the base body 134 of the sealing element 128. Figure 3 1 shows a cross section of a base body 110 of a housing 104 of a battery pack 100 .

[0051] The dimensions of first sealing lip 138, in particular first height 142, are designed to vary. Sealing element 128 has connecting elements 150, which correspond to connecting elements (not shown) of housing 104 of battery pack 100 and hold sealing element 128 when mounted on at least one housing part 108. Sealing element 128 has, for example, four connecting elements 150, which are designed in a T-shape and extend inwardly from base body 134 of sealing element 128 perpendicularly to sealing lips 138, 140.

[0052] Corresponding to the region 118 of the housing 104 where the increased deformation of the housing 104 occurs, the sealing element 128 has a region 152 of increased size, in particular increased height. In this case, the increase in the middle of the corresponding region 152 of the sealing element 128 is, for example, a maximum of 20%.

[0053] The sealing unit 124 has a second sealing element (not shown) which seals the housing 104 in the region of the further connecting plate.

Claims

1. A battery pack, in particular a replaceable battery pack, having A housing (104), wherein The housing (104) has at least two housing parts (108), A sealing unit (122) for sealing the housing (104), wherein the sealing unit (122) has at least one sealing element (128) which is received in a receiving space (132) between the housing parts (108), It is characterized in that The sealing element (128) has exactly two sealing lips (138, 140).

2. The battery pack according to claim 1, characterized in that: The sealing element (128) is arranged radially between the first housing component (108) and the second housing component (108).

3. The battery pack according to claim 2, characterized in that: The first housing part (108) is designed as a connecting plate (112) and the second housing part (108) is designed as an especially tubular base body (110).

4. The battery pack according to any one of the preceding claims, characterized in that The second sealing lip (140) has a smaller height (144) than the first sealing lip (138).

5. The battery pack according to any one of the preceding claims, characterized in that The second sealing lip (140) has a smaller width (145) than the first sealing lip (138).

6. A battery pack according to any one of the preceding claims, characterised in that A distance between the first sealing lip (138) and the second sealing lip (140) is configured to be smaller than a width of the first sealing lip (138).

7. A battery pack according to any one of the preceding claims, characterised in that The receiving space (132) has constant dimensions in the region of the sealing element (128), in particular in the region of the first sealing lip (138).

8. A battery pack according to any one of the preceding claims, characterised in that The sealing element (128), in particular the first sealing lip (138), is enlarged in area.

9. The battery pack according to claim 8, characterized in that: The enlargement of the first sealing lip (138) is configured in a range between 5% and 50%, preferably in a range between 10% and 20%.

10. A battery pack according to any one of the preceding claims, characterised in that The second sealing lip (140) varies in its dimensions.

11. A battery pack according to any one of the preceding claims, characterised in that The sealing element (128) has at least one connecting element (150) for connecting the sealing element (128) to the first housing part (108) and / or the second housing part (108) in a non-positive and / or positive manner.

12. A battery pack according to any one of the preceding claims, characterised in that A single sealing element (128) is arranged between the two housing parts (108).

13. A battery pack according to any one of the preceding claims, characterised in that The second housing part (108) consists of a metallic material and has a thickness of less than 1.1 mm, preferably less than 0.8 mm.

14. A battery pack according to any one of the preceding claims, characterised in that The second housing part (108) consists of plastic and has a thickness of less than 2.0 mm, preferably less than 1.5 mm.

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