Potting compound as cell holder in an accumulator

Abstract

Accumulator, in particular as an energy storage unit for a power tool, comprising at least one energy storage cell, a control unit, and an accumulator housing. The at least one energy storage cell is at least partially enclosed by at least a first portion of a first potting compound and retained in the accumulator housing.

Description

[0001] 2024I D00183

[0002] Hilti Aktiengesellschaft in Schaan

[0003] Principality of Liechtenstein

[0004] Potting compound as cell holder in accumulator

[0005] The present invention relates to a battery, in particular as an energy storage unit for a machine tool, comprising at least one energy storage cell, a control unit and a battery housing.

[0006] Furthermore, the present invention relates to a method for manufacturing an accumulator, in particular as an energy storage unit for a machine tool, comprising at least one energy storage cell, a control unit and an accumulator housing.

[0007] Rechargeable batteries with individual cells, securely held within a battery housing by a cell carrier, are a well-established, removable power supply for electric power tools. The battery cells serve to absorb, store, and release electrical energy. To discharge the battery, the electrical energy stored in the cells is transferred to a battery interface via a cell connector. To charge the battery, electrical energy is transferred from a charging device to the cells via the battery interface and the cell connector. Generally, commercially available rechargeable batteries are often too heavy and complex. Furthermore, these batteries do not offer optimal protection against moisture and dirt ingress.

[0008] The object of the present invention is therefore to solve the problem described above.

[0009] The problem is solved by the subject matter of independent claims 1 and 7. Further advantageous embodiments of the subject matter according to the invention are contained in the corresponding dependent claims.

[0010] The problem is solved in particular by an accumulator, especially as an energy storage unit for a machine tool, containing at least one energy storage cell, a control unit and an accumulator housing.

[0011] According to the invention, the at least one energy storage cell is at least partially enclosed by at least a first portion of a first potting compound and held in the battery housing. The potting compound can be a 1K or 2K potting compound made of PU (polyurethane), epoxy, silicone or the like.

[0012] The process of potting self-leveling materials into a designated cavity is called potting. This method is used, among other things, to shield sensitive electronics from harmful external influences or to protect components from espionage or fire hazards.

[0013] According to an alternative and advantageous embodiment, it may be possible for the control unit to be at least partially enclosed by at least a first portion of the first potting compound and held in the battery housing.

[0014] According to a further advantageous embodiment, it may be possible that the control unit is at least partially enclosed and held in the battery housing by at least a second portion of the first potting compound and / or by at least a first portion of a second potting compound.

[0015] In a further advantageous embodiment, it may be possible that at least one recess is included in the first and / or second potting compound, so that at least one cooling flow can flow to cool the first and / or second potting compound.

[0016] The recess can have an essentially circular cross-section. The recess can also be described as a bore, opening, or channel.

[0017] According to a further advantageous embodiment, it may be possible that at least one predetermined breaking point is included in the first and / or second potting compound for the targeted separation and release of the at least one energy storage cell and / or control unit from the first and / or second potting compound.

[0018] According to another advantageous embodiment, it may be possible for at least one energy storage cell to be designed in a cylindrical shape or in the form of a pouch cell.

[0019] According to a further advantageous embodiment, at least one reinforcing element may be included in the first or second casting compound. The reinforcing element may also be referred to as reinforcement or reinforcement. According to a further advantageous embodiment, the nominal voltage may be less than 80 volts.

[0020] Furthermore, the problem is solved by a method for manufacturing an accumulator, in particular as an energy storage unit for a machine tool, comprising at least one energy storage cell, a control unit and an accumulator housing.

[0021] The invention includes the following process steps:

[0022] - Inserting at least one energy storage cell into a battery casing;

[0023] - Introducing at least a first portion of a first potting compound into the battery housing to at least partially enclose the at least one energy storage cell, so that the at least one energy storage cell is held in the battery housing by the potting compound;

[0024] - Inserting a control unit into the battery housing;

[0025] - Introducing at least a first portion of a first and / or second potting compound into the battery housing to at least partially enclose the control unit, so that the control unit is held in the battery housing by the potting compound.

[0026] According to another advantageous embodiment, it may be possible to include the following process step:

[0027] - Introducing at least one recess into the first and / or second potting compound so that at least one cooling flow can pass through the first and / or second potting compound for cooling.

[0028] According to another advantageous embodiment, it may be possible to include the following process step:

[0029] - Introducing at least one predetermined breaking point into the first and / or second potting compound for the targeted separation and release of the at least one energy storage cell and / or control unit from the first and / or second potting compound. Further advantages will become apparent from the following description of the figures. The figures illustrate various embodiments of the present invention.

[0030] The figures, the description, and the claims contain numerous features in combination. A person skilled in the art will expediently consider these features individually and combine them into meaningful further combinations.

[0031] They show:

[0032] Figure 1 shows a side view of an accumulator according to a first embodiment of the invention, with an accumulator housing in a closed state;

[0033] Figure 2 shows a side view of an accumulator according to the invention in the first embodiment with the accumulator housing in an open state;

[0034] Figure 3 shows a side view of the accumulator according to a second embodiment of the invention;

[0035] Figure 4 shows a side view of the accumulator according to a third embodiment of the invention;

[0036] Figure 5 shows a side view of the accumulator according to a fourth embodiment of the invention;

[0037] Figure 5 shows a side view of the accumulator according to the invention in a fifth embodiment.

[0038] Figure 7 shows a side view of the accumulator according to a sixth embodiment of the invention; and

[0039] Figure 8 shows a side view of the accumulator according to the invention in accordance with a seventh

[0040] Design. Examples of implementation:

[0041] Figure 1 shows a sectional view through an accumulator 1 according to an exemplary embodiment of the invention.

[0042] The accumulator 1 can be used as a rechargeable power source with an electric power tool. The power tool could be a hammer drill, cordless screwdriver, saw, grinder, or similar device. The power tool is not shown in the figures.

[0043] The accumulator 1 essentially contains an accumulator housing 2, a control unit 3, cell connection devices 4 and a number of energy storage cells 5.

[0044] The battery housing 2 has a top surface 2a, a bottom surface 2b, and four side walls 2c. A battery interface 7 is positioned on the top surface 2a of the battery housing 2. The battery housing 2 also has a tray 2d and a cover 2e. As indicated in Figure 2, the cover 2e can be removed from the tray 2d in the direction of the arrow. When the cover 2e is removed from the tray 2d, the battery housing 2 is open, providing access to the interior of the battery housing 2 and the tray 2d. The battery interface 7 allows the battery 1 to be detachably connected to a machine tool. The machine tool is not shown in the figures. Furthermore, the battery interface 7 allows the battery 1 to be detachably connected to a charging device. The charging device is also not shown in the figures.

[0045] The control unit 3 serves to control and regulate the various functions of the accumulator 1. The control unit 3 is arranged in an upper part of the accumulator housing 2 in the direction of arrow R. Furthermore, the control unit 3 is connected to the accumulator interface 7 in such a way that electrical energy can be conducted from the control unit 3 to the accumulator interface 7 or from the accumulator interface 7 to the control unit 3.

[0046] The energy storage cells 5 can also be called accumulator cells, battery cells, secondary cells or energy cells and are arranged inside the battery housing 2.

[0047] The energy storage cells 5 serve to absorb, store, and release electrical energy. The energy storage cells 5 are cylindrical and based on lithium-ion technology. Each energy storage cell 5 has a first terminal contact at one end and a second terminal contact at the other. The first terminal contact can be referred to as the positive terminal and the second terminal contact as the negative terminal. The terminal contacts 5a and 5b serve to close an electrical circuit and to transfer electrical energy to or from the energy storage cell 5.

[0048] Alternatively, the energy storage cells can also be based on a different suitable technology than lithium-ion. It is also possible that different technologies are used in a single accumulator 1 for the energy storage cells 5.

[0049] Figure 1 shows an accumulator 1 according to a first embodiment. According to the first embodiment, the energy storage cells 5 are cylindrical and embedded in a first potting compound V1. The energy storage cells 5 are held solely by the first potting compound V1. Therefore, the accumulator 1 does not require a separate or independent cell holder to hold the energy storage cells 5 in position inside the battery housing 2. As also shown in Figure 1, the control unit 3 is positioned above the energy storage cells 5 inside the battery housing 2 in the direction of arrow A. The control unit 3 is embedded in a second potting compound V2. As indicated, a gap 8 is provided between the control unit 3 embedded in the second potting compound V2 and the energy storage cells 5 embedded in the first potting compound V1.The distance 8 between the control unit 3 and the energy storage cells 5 serves firstly for electrical insulation and secondly for a cooling current KS to cool the energy storage cells 5 and control unit 2.

[0050] As also indicated in Figure 1, the energy storage cells and the control unit are connected. The connection 6 is designed in the form of a plug and serves to transmit electrical energy and signals. Various data and information can be exchanged between the energy storage cells 5 and the control unit 3 using these signals. According to the first embodiment of the accumulator 1, the plugs for the connection 6 between the energy storage cells 5 and the control unit 2 are not potted with a potting compound.

[0051] The potting compound V1, V2 is a one-component epoxy potting compound. According to the first embodiment, the first and second potting compounds V1 and V2 consist of the same material. Alternatively, in an accumulator 1 according to the first embodiment, the first potting compound V1 can consist of a first material (e.g., epoxy) and the second potting compound V2 of a second material (e.g., silicone).

[0052] Figure 1 shows an accumulator 1 according to a second embodiment. The second embodiment of the accumulator 1 differs from the first embodiment in that a plurality of recesses 11 are contained in the first potting compound V1. Alternatively or additionally, such recesses 11 can also be contained in the second potting compound V2.

[0053] One or more cooling streams KS flow through the cutouts to cool the accumulator 1. A cooling stream KS can enter and exit the accumulator housing 2 through ventilation openings 9.

[0054] Figure 4 shows a battery 1 according to a third embodiment. The third embodiment of the battery 1 differs from the first embodiment in that the connection 6, designed as a plug, between the energy storage cells 5 and the control unit 2 is potted with a first potting compound V1. The potting of the connection 6 serves to protect it against moisture and dirt.

[0055] Figure 5 shows an accumulator 1 according to a fourth embodiment. The fourth embodiment of the accumulator 1 differs from the first embodiment of the accumulator 1 in that a number of predetermined breaking points 12 are included in the first potting compound V1. As indicated in Figure 5, the predetermined breaking points 12 are formed by a first and second row R1, R2 of recesses.

[0056] Figure 6 shows an accumulator 1 according to a fifth embodiment. The fifth embodiment of the accumulator 1 differs from the first embodiment in that a number of reinforcing elements 13a, 13b are contained in the first potting compound V1. In the present fifth embodiment, a first long reinforcing element 13a is inserted in an orientation along the direction of arrow C or D, and five short reinforcing elements 13b are inserted in an orientation along the direction of arrow A or B in the first potting compound V1.

[0057] Figure 7 shows an accumulator 1 according to a sixth embodiment. The sixth embodiment of the accumulator 1 differs from the previously mentioned embodiments in that the energy storage cells 5 are designed in pouch form. As indicated in Figure 7, a spacer mat 14 is provided between each pair of adjacent pouch-shaped energy storage cells 5. The pouch-shaped energy storage cells 5 are encased in a first potting compound V1. The control unit 2, arranged above the energy storage cells 5 in the direction of arrow A, is encased in a second potting compound V2.

[0058] Figure 8 shows an accumulator 1 according to a seventh embodiment. The seventh embodiment of the accumulator 1 differs from the sixth embodiment of the accumulator 1 in that the pouch-shaped energy storage cells 5 and the control unit 2 are only encased in the first potting compound V1. Support elements 10 are positioned between the pouch-shaped energy storage cells 5 and the control unit 2.

[0059] 1 accumulator

[0060] 2 battery housings

[0061] 2a Top of the battery housing

[0062] 2b Underside of the battery housing

[0063] 2c Side panel of the battery housing

[0064] 2d Battery housing tray

[0065] 2e Battery housing cover

[0066] 3 Control unit

[0067] 4 cell connection device

[0068] 5 Energy storage cell

[0069] 6 connection

[0070] 7 Battery interface

[0071] 8 Distance between control unit and energy storage cells 9 Ventilation opening in battery housing

[0072] 10 support elements

[0073] 11 recess

[0074] 12 Breakaway point

[0075] 13a, 13b Reinforcing element

[0076] 14 spacer mat

[0077] V1 first potting compound

[0078] V2 second potting compound

[0079] R1 first row of predetermined breaking points

[0080] R2 second row of predetermined breaking points

[0081] KS Cooling Stream

Claims

Patent claims 1. Accumulator (1), in particular as an energy storage unit for a machine tool, comprising at least one energy storage cell (5), a control unit (3) and an accumulator housing (2), characterized in that the at least one energy storage cell (5) is at least partially enclosed by at least a first portion of a first potting compound (V1) and held in the battery housing (2).

2. Accumulator (1) according to claim 1 , characterized in that the control unit (3) is at least partially enclosed by the at least first part of the first potting compound (V1) and held in the battery housing (2).

3. Accumulator (1) according to claim 1 or 2, characterized in that the control unit (3) is at least partially enclosed by at least a second part of the first potting compound (V1) and / or by at least a first part of a second potting compound (V2) and is held in the battery housing (2).

4. Accumulator (1) according to at least one of claims 1 to 3, characterized in that at least one recess (11) is included in the first and / or second potting compound (V1 , V2) so that at least one cooling flow (KS) can flow to cool the first and / or second potting compound (V1, V2).

5. Accumulator (1) according to at least one of claims 1 to 4, characterized in that at least one predetermined breaking point (12) is included in the first and / or second potting compound (V1, V2) for the targeted separation and triggering of the at least one energy storage cell (5) and / or control unit (3) from the first and / or second potting compound (V1 , V2).

6. Accumulator (1) according to at least one of claims 1 to 5, characterized in that the at least one energy storage cell (5) is configured in a cylindrical shape or in the form of a pouch cell.

7. Accumulator (1) according to at least one of claims 1 to 6, characterized in that at least one reinforcing element (13a, 13b) is contained in the first or second potting compound (V1, V2).

8. Accumulator (1) according to at least one of claims 1 to 7, characterized by the fact that the nominal voltage is less than 80 volts.

9. Method for manufacturing an accumulator (1), in particular as an energy storage unit for a machine tool, comprising at least one energy storage cell (5), a control unit (3) and an accumulator housing (2), characterized by the process steps: - Inserting at least one energy storage cell (5) into a battery housing (2); - Introducing at least a first portion of a first potting compound (V1) into the battery housing (2) to at least partially enclose the at least one energy storage cell (5), so that the at least one energy storage cell (5) is held in the battery housing (2) by the potting compound (V1); - Inserting a control unit (3) into the battery housing (2); - Introducing at least a first portion of a first and / or second potting compound (V1, V2) into the battery housing (2) to at least partially enclose the control unit (3), so that the control unit (3) is held in the battery housing (2) by the potting compound.

10. Method for manufacturing an accumulator (1) according to claim 9, characterized by the method steps: - Introducing at least one recess (11) into the first and / or second potting compound (V1, V2) so that at least one cooling flow (KS) can flow through the first and / or second potting compound (V1, V2) for cooling.

11. Method for manufacturing an accumulator (1) according to claim 9 or 10, characterized by the method steps: - Introducing at least one predetermined breaking point (12) into the first and / or second potting compound (V1 , V2) for the targeted separation and triggering of the at least one energy storage cell (5) and / or control unit (3) from the first and / or second potting compound (V1, V2).

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