Battery pack having at least one protective element

Abstract

The invention relates to a battery pack, in particular for a hand-held power tool, comprising a housing in which at least one battery cell and at least one protective element are arranged, said protective element being designed to protect the battery pack when a force acts and / or punctures. According to the invention, the protective element is arranged on the outer side of the housing of the battery pack.

Description

Technical Field

[0001] The invention relates to a battery pack, in particular a battery pack for a handheld power tool. Background Art

[0002] DE 10 2018 210 663 A1 describes a handheld power tool having a protective element, wherein the protective element is accommodated in a housing of the handheld power tool. Summary of the invention

[0003] The invention relates to a battery pack, in particular a battery pack for a handheld power tool, comprising a housing in which at least one battery cell is arranged, and at least one protective element, which is designed to protect the battery pack in the event of force and / or puncture. It is proposed that the protective element is arranged on the outer side of the housing of the battery pack. Advantageously, this can achieve effective protection of the battery pack.

[0004] The battery pack is in particular part of a system composed of a battery pack and an electrical consumer, wherein the electrical consumer is supplied with energy during operation via the battery pack. The battery pack is in particular configured as a portable power tool battery pack. The battery pack is in particular configured as a replaceable battery pack. The battery pack is in particular configured to be connectable to a charging device for charging the battery pack. The battery pack is in particular configured as a replaceable battery pack. Alternatively, the electrical consumer may also be configured as a forward device, such as an electric bicycle, a household appliance, such as a vacuum cleaner, a gardening tool, such as a hedge shear or a measuring tool.

[0005] The housing of the battery pack is preferably configured as a shell. The battery pack, in particular the housing of the battery pack, can be detachably connected to an electrical consumer and / or a charging device via a mechanical interface. The housing of the battery pack may have one or more housing parts. The battery pack may have a cell holder, which is configured to receive and / or fix a battery cell in the housing. The cell holder preferably has a single cell receiving portion, which is respectively configured to receive a single battery cell. Preferably, the cell holder is configured as one of the housing parts. The housing parts are connected to each other in a force-locking, form-locking and / or material-locking manner. The cell holder is preferably composed of plastic, in particular thermoplastic. The cell holder may partially constitute the housing of the battery pack. The cell holder is preferably constructed in one piece or in one piece. In the context of the present invention, "in one piece" should be understood in particular as being composed of one piece, rather than being composed of a plurality of components that are connected to each other in a material-locking and / or force-locking and / or form-locking manner. Therefore, the integral component is composed of a single material. In the context of the present invention, "one-piece" is to be understood in particular as a one-piece component or a plurality of components that are connected to one another in a material-locked manner, for example by two-component injection molding. Alternatively, it is also conceivable that the one-piece holder is constructed in multiple parts, wherein the different parts are connected to one another in a force-locking and / or material-locking manner.

[0006] The battery pack can be connected to the electrical load by force locking and / or form locking via a mechanical interface. Advantageously, the mechanical interface includes at least one operating element, through which the connection between the battery pack and the electrical load and / or the charging device is detachable. The operating element can be configured as a button, a lever or a key, for example. In addition, the battery pack has at least one electrical interface, through which the battery pack can be electrically connected to the electrical load and / or the charging device. The battery pack can be charged and / or discharged, for example, via an electrical connection. Alternatively or additionally, it is also conceivable that information can be transmitted via the electrical interface. The electrical interface is preferably configured as a contact interface, in which the electrical connection is achieved by physical contact between 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. Alternatively or additionally, the electrical interface may have a secondary charging coil element for inductive charging. Furthermore, at least one battery cell may be arranged in the housing of the battery pack, which battery cell can be electrically connected to an electrical load via an electrical contact arrangement.

[0007] The battery cell can be constructed as a galvanic 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. The battery voltage of the battery pack is usually a multiple of the voltage of the individual battery cells and is obtained from the circuit (parallel or series connection) of the battery cells. Thus, in the case of a common battery cell with a voltage of 3.6V, a battery voltage of 3.6V, 7.2V, 10.8V, 14.4V, 18V, 36V, 54V, 108V, etc. is generated, for example. Preferably, the battery cell is constructed as an at least substantially cylindrical round cell, wherein the cell poles are arranged at the ends of the cylindrical shape.

[0008] In addition, the battery pack preferably includes an electronic device. The electronic device may include a storage unit on which information is stored. Additionally or alternatively, it is also conceivable that the information is obtained by the electronic device. This information may be, for example, the state of charge of the battery pack, the temperature in the battery pack, the coding or the remaining capacity of the battery pack. It is also conceivable that the electronic device is configured to regulate or control the charging and / or discharging process of the battery pack. The electronic device may, for example, have a calculation unit, a control unit, a transistor, a capacitor and / or a storage unit. 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. The electronic device may alternatively or additionally have a coding element, such as a coding resistor.

[0009] The outer side of the housing faces away from the inner side of the housing of the battery pack. The inner side of the housing faces the battery cells. The protective element is designed in such a way that, for example, if the battery pack falls on the ground or on a sharp or pointed object, such as a nail, the impact on the housing is particularly significantly reduced. The protective element is preferably made of a different material than the battery pack housing. The protective element is designed in particular in such a way that the forces acting on the battery pack housing are reduced by elastic and / or plastic deformation of the protective element. The deformation can be reversible or completely irreversible.

[0010] It is further proposed that the battery pack has a placement surface arranged on the side of the battery pack opposite the mechanical interface. In particular, at least one protective element is arranged in the region of the placement surface. Advantageously, protection can be optimized thereby. Alternatively or additionally, it is conceivable to arrange it in the edge region or on the side adjacent to the placement surface of the battery pack. Alternatively or additionally, it is also conceivable that at least one protective element is arranged in the region of the mechanical interface.

[0011] In addition, it is proposed that at least one protective element is configured to be materially or forcefully locked and / or form-locked with the housing of the battery pack. The material lock can be achieved, for example, by bonding. In addition, the protective element can also be configured to be partially injection-molded by the housing of the battery pack and / or to be injection-molded onto the housing of the battery pack.

[0012] Furthermore, it is proposed that the protective element is connected to the housing in a movable, in particular rotationally movable manner. Advantageously, the force effect can be reduced by the relative movement of the protective element relative to the housing.

[0013] It is further proposed that the protective element is designed such that a cavity is formed between the protective element and the housing, wherein at least one side of the cavity is open, wherein at least one side of the cavity is open, wherein the open side of the cavity extends in particular along at least the longitudinal extension of the battery cell. Preferably, the cavity is open on at least two, preferably at least three adjacent sides. The protective element is designed in particular such that the cavity decreases when a force acts.

[0014] Furthermore, it is proposed that the protective element only partially covers the placement surface. In this case, the coverage is in particular less than 90% of the placement surface, preferably 50% of the placement surface, advantageously 30% of the placement surface. Advantageously, the weight of the battery pack can be reduced thereby.

[0015] Alternatively or additionally, it is proposed that at least one protective element is formed integrally with the housing. In particular, the protective element extends obliquely to the placement surface of the battery pack.

[0016] Preferably, the protective element extends in a range between 20° and 60° relative to the placement surface, in particular in a range between 25° and 45° relative to the placement surface. The protective element is preferably designed as a flat surface with a constant slope relative to the placement surface. The housing can have a plurality of protective elements, wherein all protective elements preferably have the same slope. Alternatively, it is also conceivable that the protective elements have different slopes.

[0017] Furthermore, it is proposed that the battery pack has at least one further protective element, wherein the further protective element is arranged in the battery pack, wherein the further protective element is arranged between at least one battery cell and the placement surface. Advantageously, the protection of the battery pack can thereby be further optimized. Therefore, the further protective element is designed as an internal protective element.

[0018] Furthermore, it is proposed that the further protective element is designed to radially load at least one battery cell in the cell receptacle. Here, the cell receptacle is in particular part of a cell holder for receiving the battery cell. Advantageously, the fixation of the battery cell and its protection can be improved thereby.

[0019] Furthermore, it is proposed that the further protective element has a greater hardness than the housing and / or the in particular outer protective element, wherein the further protective element is in particular made of plastic. In particular, the further protective element is made of an entropic elastic material, preferably rubber. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Further advantages are obtained from the following description of the drawings. The drawings, the description and the claims contain a combination of multiple features. It is expedient for a person skilled in the art to consider these features individually and combine them into other meaningful combinations. The substantially corresponding reference numerals of the features of the different embodiments of the invention are provided with the same numbers and letters indicating the embodiment.

[0021] The accompanying drawings show:

[0022] Figure 1 : A schematic side view of a handheld power tool having a battery pack;

[0023] Figure 2 : Exploded view of the battery pack;

[0024] Figure 3 : Cross section of the battery pack in the area of ​​the protective element;

[0025] Figure 4 : In the tilted state of the protection element according to Figure 3 The cross section of the battery pack;

[0026] Figure 5 : Another embodiment of a battery pack having a protection element;

[0027] Figure 6 :according to Figure 5 A longitudinal section of a battery pack;

[0028] Figure 7 :according to Figure 5 Cross section of a battery pack. DETAILED DESCRIPTION

[0029] exist Figure 11 shows a side view of a system 10, which consists of an electrical load 14 configured as a handheld power tool 12 and a battery pack 18 configured as a battery pack 16 for a handheld power tool. Therefore, the handheld power tool 12 is configured as a battery handheld power tool and is supplied with energy by the battery pack 18 during operation. The handheld power tool 12 and the battery pack 18 each have a mechanical interface 20, 22, via which the two components of the system 10 are detachably connected to each other. Therefore, the battery pack 18 is configured as a replaceable battery pack and can be replaced by an identical or similar battery pack. The handheld power tool 12 is configured as a hammer drill, for example. Via the mechanical interface 22 of the battery pack 18, the battery is configured to be detachably connected to a charger (not shown).

[0030] The handheld power tool 12 has a housing 26, on the rear end of which a handle 28 with an operating switch 30 is arranged, which is used to switch the handheld power tool 12 on and off. A tool receptacle 31 is arranged at the front end of the housing 26 of the handheld power tool 12, which is provided for receiving an insertion tool 32. A drive unit 38 having an electric motor 34 and a transmission 36 is arranged between the handle 28 and the tool receptacle 31. The transmission 36 includes an impact unit 40 and is arranged above the electric motor 34. The impact unit 40 includes a pneumatic impact mechanism. An electronic component 42 is arranged below the electric motor 34, by which the handheld power tool 12 can be adjusted or controlled. The battery pack 18 is arranged below the handle 28 and adjacent to the electronic component 42.

[0031] Battery packs 18 and 14 each have corresponding electrical connections 44, 46, via which battery pack 18 can be electrically connected to load 14, in particular to electronics 42 of load 14. In the connected state, battery pack 18 supplies load 14 with energy.

[0032] exist Figure 2 1 shows a battery pack 18 in an exploded view. The battery pack 18 has a housing 50. The housing 50 of the battery pack 18 is made of plastic, in particular hard plastic, for example. The housing 50 of the battery pack 18 includes a plurality of housing parts 52, which are connected to each other, for example, by connecting means 54 in the form of screws.

[0033] The upper housing part 52 is configured as an interface housing part 56 and comprises the electrical interface 44 and the mechanical interface 22 of the battery pack 18. The interface housing part 56 is largely covered by the handheld power tool 12 when connected to the handheld power tool 12. The mechanical interface 22 has two guide elements 58, for example in the form of guide rails, which are configured to be guided in corresponding guide elements of the power consumption device 14 during the connection process. In addition, the battery pack 18 has a locking device with a locking element 62. The locking element 62 is configured, for example, as a movable, especially rotatable locking element 62 and is preloaded in the direction of the locking position by means of a spring element (not shown). The locking device also has an operating element 64 that is configured to be manually operable. The operating element 64 is also supported, for example, linearly movable, in the housing 50 of the battery pack 18, in particular in the interface housing part 56.

[0034] The battery pack 18 has, for example, ten battery cells 66 (see Figure 3 ). The battery cells 66 are received in the cell holder 70. The cell holder 70 is, for example, constructed in one piece and made of plastic. The cell holder 70 has an individual receiving portion per battery cell 66, into which the battery cell 66 can be inserted along its longitudinal extension. The individual cell receiving portions are, for example, constructed in a substantially closed manner. The battery cells 66 are, for example, constructed as cylindrical lithium-ion round batteries. The cell holder 70 can also be constructed in multiple pieces and / or in a partially open manner, so that the battery cells 66 are partially exposed laterally and are spaced apart from the walls of the cell holder 70.

[0035] The cell holder 70 also forms part of the housing 50 and thus forms the housing part 52. The cell holder 70 forms, for example, the region of the housing 50 opposite the connecting housing part 56 and partially forms the placement surface 68 on which the battery pack 18 can be placed by itself and / or in a state connected to the handheld power tool 12.

[0036] The housing 50 has a total of four housing parts 52, wherein the cell holder 70 is connected to the interface housing part 56 via two side housing parts 71. The connection is made, for example, by a screw connection, by means of connecting means 54. In addition, the housing 50 also has connecting means for a positive connection, for example, a cylindrical recess in the side housing part 71, for connecting to the cell holder.

[0037] An electronic device 72 is also arranged in the housing 50 of the battery pack 18. The electronic device 72 is arranged, for example, between the cell holder 70 and the interface housing part 56. The electronic device 72 includes a circuit board 74, which includes electronic components and, for example, five electrical contact elements 76. The electrical contact elements 76 are, for example, configured as contact tulips. The two external electrical contact elements 76 are, for example, configured as power contacts for energy supply. The internal electrical contact element 76 is, for example, configured as a signal contact, which is configured to transmit information to the handheld power tool 12 and / or a charger.

[0038] exist Figure 3 2 shows a cross section through a battery pack 18 . The battery pack 18 has, for example, two protective elements 80 which are designed to protect the battery pack 18 .

[0039] The battery pack 18 has, for example, two protective elements 80 which extend substantially parallel to the battery cells 66 and are arranged in the region of the placement surface 68. The length of the protective elements 80 corresponds substantially to the length of the battery cells 66. Advantageously, the protective elements 80 thus partially form the placement surface 68. The protective elements 80 are, for example, made of a material different from that of the housing 50 of the battery pack 18. The protective elements 80 are connected to the housing 50, for example, in a force-fitting and form-fitting manner. In particular, the protective elements 80 are partially arranged in a, for example, V-shaped groove 82 of the housing 50, in particular the cell holder 70, and are clamped between the two side housing parts 71.

[0040] The protective element 80 is made of thermoplastic, for example. The plastic can be PA-GF, PC / ABS or the like.

[0041] The protective element 80 is located substantially linearly in the groove 82. Due to the partial support of the protective element 80, a cavity 84 is formed between the protective element 80 and the outer side of the housing 50, in particular the outer side of the cell holder 70. Advantageously, this allows a relatively large surface area of ​​the cell holder 70 connected to the battery cells 66 to be exposed for heat conduction, so that the cell holder 70 can be cooled by air flowing around it.

[0042] If the battery pack 18 strikes an object on the ground, such as a nail or a stone, in the event of a fall, the force applied to the housing 50 or the impact energy is reduced by the protective element 80 in that the protective element 80 deforms and / or moves in the direction of the cell holder 70, so that the cavity 84 becomes smaller. The movement of the protective element 80 is in particular designed as a rotational movement, wherein the axis of rotation 83 is defined by a groove 82 in which the protective element 80 is arranged. Advantageously, foreign objects can be directed away by the movement of the protective element 80, so that the force applied to the battery cells or the damaging / puncturing forces are minimized. Figure 48 shows the protective element 80 in an inclined state.

[0043] The protective element 80 has a substantially W-shaped cross section. The protective element 80 has a V-shaped cutout 88 in the middle. The cutout 88 is designed in such a way that in the event of an intermediate force or a nail hitting in the middle, it is guided into a region of the protective element 80 and / or housing 50 where the material thickness is greater.

[0044] It is also conceivable that protective element 80 is designed as an optional element of battery pack 18 , so that battery pack 18 , in particular housing 50 of battery pack 18 , is fully functional even without protective element 80 .

[0045] exist Figure 5 1 shows an alternative embodiment of a battery pack 18a in a perspective view from below. The battery pack 18a has a similar structure to the battery pack 18 described above, but differs in the design of the protective element 80a.

[0046] As described above, the housing 50a of the battery pack 18a has four housing parts 52a, wherein the protective element 80a is formed integrally with the cell holder 70a. Therefore, the protective element 80a is arranged on the bottom side of the battery pack 18a, wherein alternatively or additionally, it is also conceivable that the protective element 80a is arranged on the side or above.

[0047] The protective elements 80a are designed as pairs of inclined surfaces that converge toward one another in a V-shaped manner. The underside of the cell holder 70a is substantially completely covered by the protective elements 80a, wherein, for example, twelve protective elements 80a are arranged per battery cell for protection.

[0048] exist Figure 6 1 shows a battery pack 18a in cross section. The placement surface 68a here defines a plane from which the protective element 80a extends obliquely inward. The angle between the placement surface 68a and the protective element 80a here exceeds 30°, for example, approximately 35°. Alternatively, a larger inclination, for example exceeding 45°, is also conceivable in order to further increase the protection.

[0049] Viewed in cross section, protective element 80a is arranged such that it has a minimum distance from placement surface 68a in the middle region of battery cells 66a and a maximum distance from placement surface 68a between battery cells 66a. In particular, protective element 80a partially forms placement surface 68a.

[0050] Alternatively to the described one-piece embodiment of the protective element 80a, it is also conceivable that the protective element 80a is constructed as a coating with a harder or more elastic material, especially plastic. It is also conceivable that the protective element 80a is composed of metal, preferably a metal insert in a receiving portion of the housing 50a provided for this purpose.

[0051] It is also conceivable that a plurality of protective elements 80a are not distributed over the entire placement surface 68a but are used only at critical locations, such as where housing 50a of battery pack 18a , in particular cell holder 70a , has a weaker material thickness.

[0052] Furthermore, the rechargeable battery pack 18a has a further protective element 90a which is provided for protecting the rechargeable battery cells 66a.

[0053] The additional protective element 90a is particularly configured as an internal protective element, which is arranged inside the housing 50a of the battery pack 18a, in particular on the inner side of the housing 50a of the battery pack 18a. For example, the housing 50a of the battery pack 18a has a protective element receiving portion 92a on its inner side, which is configured to receive the additional protective element 90a. The protective element receiving portion 92a is adjacent to the single cell receiving portion 94a of the cell holder 70a. The single cell receiving portion 94a of the cell holder 70a is configured to receive a single battery pack 66a respectively. The single cell receiving portion 94a is configured in a hollow cylindrical shape and its diameter substantially corresponds to the diameter of the battery cell 66a. The single cell receiving portion 94a has an axial opening (not shown) for receiving the battery cell 66a and a radially surrounding wall 96a. The wall 96a is substantially closed and, for example, is only interrupted by the protective element receiving portion 92a.

[0054] The additional protective element 90a is, for example, made of elastic plastic, in particular soft plastic. In particular, the additional protective element 90a has greater elasticity than the housing 50a, in particular the cell holder 70a. Preferably, the additional protective element 90a is made of an entropy elastic material, which has an increased robustness due to the favorable distribution of the introduced energy when a damaging object is pierced. The additional protective element 90a is also configured so that a radially inwardly directed force is applied to the battery cell 66a by the additional protective element 90a, in order to fix the battery cell 66a in the individual cell receiving portion 94a.

[0055] The battery pack 18a may have one or more additional protective elements 90a per battery cell 66a. Figure 7 As shown in cross section in FIG. 1 , the battery pack 18 a has two further protective elements 90 a per battery cell 66 a which extend coaxially with respect to one another along the longitudinal extension of the battery cell 66 a .

[0056] Alternatively, it is also conceivable that further protective element 90a has a greater hardness than housing 50a of rechargeable battery pack 18a, in particular cell holder 70a. This can be achieved, for example, by a plastic or metal, in particular a metal sheet, having a higher hardness.

[0057] In order to optimally protect the battery cells 66a against damage, the further protective element 90a and the protective element 80a are arranged on different sides of the housing 50 , in particular of the cell holder 70a , relative to one another.

Claims

1. A battery pack, in particular a battery pack (18) for a handheld power tool (12), comprising: a housing (50) in which at least one battery cell (66) is arranged, at least one protective element (80) which is designed to protect the battery pack (18) in the event of force and / or puncture, It is characterized in that The protective element (80) is arranged on an outer side of a housing (50) of the battery pack (18).

2. The battery pack according to claim 1, characterized in that: The battery pack (18) has a mechanical interface (22) for detachably connecting to an electrical load (14), in particular a handheld power tool (12).

3. The battery pack according to any one of the preceding claims, characterized in that The battery pack (18) has a placement surface (68) which is arranged on a side of the battery pack (18) opposite the mechanical interface (22).

4. The battery pack according to any one of the preceding claims, characterized in that The at least one protective element (80) is arranged in the region of the placement surface (68).

5. The battery pack according to any one of the preceding claims, characterized in that The at least one protective element (80) is designed to be integrally bonded or forcefully and / or positively bonded to the housing (18) of the battery pack (18).

6. A battery pack according to any one of the preceding claims, characterised in that The protective element (80) is connected to the housing (50) in a movably, in particular rotationally, manner.

7. A battery pack according to any one of the preceding claims, characterised in that The protective element (80) is designed to form a cavity (84) between the protective element (80) and the housing (50), wherein at least one side of the cavity (84) is open, wherein the open side of the cavity (84) extends in particular along at least a longitudinal extension of the battery cell (66).

8. A battery pack according to any one of the preceding claims, characterised in that The protective element (80) only partially covers the placement surface (68).

9. A battery pack according to any one of the preceding claims, characterised in that The at least one protective element (80a) and the housing (50a) are formed integrally.

10. A battery pack according to any one of the preceding claims, characterised in that The at least one protective element (80a) extends obliquely relative to the placement surface (68a).

11. A battery pack according to any one of the preceding claims, characterised in that The protective element (80a) extends in a range between 20° and 60° relative to the placement surface (68a), in particular in a range between 25° and 45° relative to the placement surface (68a).

12. A battery pack according to any one of the preceding claims, characterised in that The battery pack (18a) has at least one further protective element (90a), wherein the further protective element (90a) is arranged in the battery pack (18a), wherein the further protective element (90a) is arranged between the at least one battery cell (66a) and the placement surface (68a).

13. The battery pack according to claim 12, characterized in that: The further protective element (90a) is designed to act radially on at least one battery cell (66a) in a cell receptacle, in particular an individual cell receptacle (94a).

14. The battery pack according to claim 12 or 13, characterized in that: The further protective element (90a) has a greater hardness than the housing (50a) and / or the protective element (80a), wherein the further protective element (90a) is made, in particular, of plastic.

15. The battery pack according to any one of claims 12 to 14, characterized in that: The further protective element (90a) consists of an entropic elastic material, in particular rubber.

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