Voltage supply device
The device and method manage sodium-ion battery cell voltages by switching cells in or out of the circuit to maintain the total voltage within the 10.5 V to 15 V range, addressing the voltage range challenge of sodium-ion batteries and ensuring stable operation of 12 V appliances.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- BOS BALANCE OF STORAGE SYST
- Filing Date
- 2025-11-04
- Publication Date
- 2026-05-15
AI Technical Summary
Sodium-ion battery cells exhibit a wide voltage range, making it challenging to achieve the nominal voltage ranges of 12 V appliances, as a series connection results in voltages outside the required 10.5 V to 15 V range, especially when fully discharged or fully charged.
A device and method using a series circuit with battery cells connected in series, where individual cells or groups can be switched in or out via a bypass line and switching elements to maintain the total voltage within the nominal range, controlled by a control unit based on measured voltages and currents.
The solution ensures that the total voltage of the series circuit remains within the desired nominal range by selectively activating or deactivating cells, allowing uniform charging and discharging without exceeding voltage limits, thus supporting the operation of 12 V appliances.
Smart Images
Figure EP2025081849_15052026_PF_FP_ABST
Abstract
Description
[0001] BOS Balance of Storage Systems AG Industriestr. 12, 89081 Ulm
[0002] Device for power supply
[0003] TECHNICAL AREA
[0004] The present invention relates to a device for supplying voltage to at least one load with a nominal voltage range by means of several battery cells connected in series. The invention also relates to a method for controlling the total electrical voltage of a series circuit and a method for controlling the charging voltage of battery cells connected in series in at least one series circuit.
[0005] Whenever this application refers to a "nominal voltage range," it always means a specific range of values. For a nominal voltage of 12 V, this refers to a range of approximately 10.5 V to approximately 15 V. The same applies to applications and vehicle electrical systems with a nominal voltage of 24 V, 36 V, or 48 V, where the respective nominal voltage range is also limited by a lower and an upper limit.
[0006] Where this application refers to a "battery cell", this may also include a group of several battery cells connected in parallel, whereby the parallel battery cells are then connected in series in groups.
[0007] STATE OF THE ART
[0008] Currently, lead-acid or lithium-ion batteries are primarily used to power electrical appliances in motorhomes and caravans. These batteries, with 12V or multiples thereof (24V, 48V), are also commonly used as starter and auxiliary batteries in vehicles, construction equipment, and boats. In modern vehicles with regenerative braking, the distinction between starter and auxiliary batteries becomes blurred.
[0009] 102396-WO1 GWI Keller Schneider
[0010] November 4, 2025 Patent and Trademark Attorneys This is increasingly being lifted, which can lead to a limited lifespan, especially for lead-acid batteries. These batteries deliver an operating voltage that fluctuates only slightly, regardless of the state of charge, and which covers the nominal voltage range of common consumers specified above. Alternatively, the standard nominal voltage range of many devices was adapted to the operating voltage of lead-acid batteries and did not need to be adjusted for the use of lithium-ion batteries.
[0011] The use of sodium-ion battery cells offers several advantages in the automotive sector, particularly as starter or auxiliary batteries in motorhomes and caravans:
[0012] • Insensitive to complete discharge and operation at extremely low or high temperatures
[0013] • High C rates, i.e., particularly fast charging and discharging, such as charging a caravan battery in half an hour or briefly operating inverters or large consumers with several kW of power on small batteries.
[0014] A disadvantage is that the battery cell has a wide voltage range: When completely discharged, it has 0 V (without being damaged), and the typical operating range is approximately 2 V to 4 V per cell. Therefore, the nominal voltages of 12 V known from lead-acid batteries, with an operating range of approximately 10.5 V to 15 V, cannot always be achieved with a standard series connection of sodium-ion battery cells. For example, a series connection of five such sodium-ion battery cells would be discharged at approximately 10 V and fully charged at approximately 20 V, which does not match the nominal voltage range of many common 12 V appliances.
[0015] This problem was already described in document CN000115053377A, which proposed a DC / DC converter as a solution. This converter is either integrated into the battery pack or connected between the battery and the application. This approach—using a DC / DC converter to adapt the wide voltage range of PV modules to the relatively narrow operating voltage range—is already known as state of the art in other applications, such as charging a battery from PV modules. It is also used, for example, in MPPT charge controllers to adapt the fluctuating PV voltage to the relatively constant battery voltage.
[0016] 102396-WO1 GWI Keller Schneider
[0017] November 4, 2025 Patent and Trademark Attorneys TASK
[0018] Based on the prior art described above, the object of the present invention is to provide a device for supplying voltage to at least one consumer operable in a nominal electrical voltage range by means of at least one series circuit with several battery cells connected in series, a method for controlling the total electrical voltage of a series circuit of battery cells connected in series within the nominal voltage range of at least one consumer, and a method for controlling the charging voltage of several battery cells connected in series in at least one series circuit, which enables the production of a desired total voltage in a predefinable nominal voltage range using simple means.
[0019] REVELATION OF THE INVENTION
[0020] The problem is solved by a device for supplying power according to claim 1 and with regard to the methods by the features of claims 8 and 9. Further developments of the invention are the subject of the dependent claims.
[0021] What applies to the device and the method for supplying power also applies, conversely, to the charging process of several battery cells connected in series. The invention is therefore suitable for both the discharge management of a series connection of battery cells and for their charging management.
[0022] According to the invention, a device for supplying voltage to at least one consumer operable within a nominal electrical voltage range is characterized by at least one series circuit with several battery cells connected in series in that all battery cells connected in series in a series circuit, when fully charged, generate a total voltage that is above the nominal voltage range of the at least one consumer, and that individual battery cells or groups of battery cells can be switched into or out of the series circuit by means of at least one bypass line arranged in parallel to the series circuit and several switching elements arranged in the series circuit and / or the bypass line, in order to bring the current total voltage of the series circuit into conformity with the nominal voltage range of the at least one consumer.
[0023] 102396-WO1 GWI Keller Schneider
[0024] November 4, 2025 Patent and Trademark Attorneys As described in the introduction, the invention relates in particular to battery cells whose voltage fluctuates significantly depending on the state of charge. Battery cells are considered to fluctuate significantly depending on the state of charge if the difference in voltage between a single battery cell and its empty state of charge alters the overall voltage of the series connection in such a way that the limits of the nominal voltage range are exceeded or fallen below. The cell voltage of the individual batteries fluctuates significantly, especially within a state of charge of 10% to 90%. Particularly preferably, a fluctuation of at least 20%, preferably at least 50%, and most preferably at least 80% of the lower value within a state of charge of 10% to 90% is considered to be significant.If the cell voltage is, for example, 2V at a charge level of 10%, the cell voltage at 90% will be at least 2.4V, 3V or 4V.
[0025] Sodium-ion battery cells are particularly important in this context, as their cell voltage can fluctuate between, for example, 0 V and 4 volts. Alternatively or additionally, zinc-manganese and / or zinc-carbon battery cells can also be used. Hybrid forms of these battery cell types – even with other battery technologies – can also be connected in series or parallel circuits.
[0026] In particular, all battery cells connected in series in a series circuit, when almost empty or at the start of charging, produce in sum at least a total voltage that is within the nominal voltage range, in particular above the minimum nominal voltage, of at least one consumer.
[0027] In other words, all battery cells connected in series in a series circuit, when fully charged, produce a total voltage that is at least 120%, and particularly preferably at least 150%, above the nominal voltage range, especially the maximum nominal voltage, of at least one consumer.
[0028] Thus, according to the invention, the total electrical voltage, provided all battery cells are fully charged, can be reduced by temporarily switching off individual battery cells.
[0029] 102396-WO1 GWI Keller Schneider
[0030] November 4, 2025 Patent and trademark attorneys selectively reduce cells or groups of battery cells and increase them again when the charge level of the active battery cells decreases by selectively switching on previously deactivated battery cells.
[0031] In a preferred embodiment of the present invention, the total voltage and / or the voltage of the individual battery cells or groups of battery cells is measured using a voltmeter.
[0032] Particularly preferably, the device includes a control unit to which the total voltage and / or the values of the individual voltmeters of the battery cells can be supplied as input values via at least one measuring line.
[0033] According to an advantageous embodiment of the invention, the control unit is connected to the switching elements for their control via at least one control line. The control line can be designed as a data bus, so that the control commands are recognized by the respective switching element via an addressing code. Alternatively, each switching element can be connected to the control unit via a separate control line.
[0034] In a program memory of the control unit, at least one algorithm is preferably stored which, depending on the measured actual voltage values of the individual battery cells, the total voltage and preferably the nominal voltage, in particular the nominal voltage range, of the consumer, selectively switches individual battery cells or groups of battery cells into the series circuit or switches them out of it using the bypass line.
[0035] Optionally, current measurement is also performed if the voltage changes depending on the charging or discharging current, in order to be able to switch using the algorithm depending on voltage and current.
[0036] The switching elements, also referred to as switches in the description, are particularly preferably formed by a relay, a transistor or one or more MOSFETs, with switching elements with a low required control current for controlling the switching operations being particularly preferred.
[0037] 102396-WO1 GWI Keller Schneider
[0038] November 4, 2025 Patent and Trademark Attorneys An inventive method for controlling the total electrical voltage of a series-connected battery cells to the nominal voltage range of at least one consumer comprises the following process steps, wherein at least some of the battery cells (B1....B6) are sodium-ion battery cells and / or zinc-manganese (Zn-Mn) battery cells and / or zinc-carbon (Zn-C) battery cells:
[0039] Measuring the total voltage and / or the individual voltage values of the battery cells and supplying these measured values to a control unit,
[0040] Program-controlled coupling of at least one battery cell from the series circuit by means of at least one switching element arranged in the series circuit and / or in a bypass line arranged parallel to the series circuit by the control unit, in particular depending on the nominal voltage range of the at least one consumer.
[0041] An inventive method for controlling a charging voltage of several battery cells connected in series in at least one series circuit, wherein at least part of the battery cells (B1....B6) are sodium-ion battery cells and / or zinc-manganese (Zn-Mn) battery cells and / or zinc-carbon (Zn-C) battery cells, is characterized by the following process steps:
[0042] Measuring the total voltage and / or the individual voltage values of the battery cells and supplying these measured values to a control unit,
[0043] Program-controlled coupling of at least one battery cell from the series circuit by means of at least one switching element arranged in the series circuit and / or in a bypass line arranged parallel to the series circuit by the control unit.
[0044] Optional adjustment of parameters such as the charging voltage to the currently selected series connection, for example, adjusting the maximum permissible charging voltage depending on the selected series connection, for example to prevent overcharging of individual cells during load changes or sudden load shutdown.
[0045] 102396-WO1 GWI Keller Schneider
[0046] November 4, 2025 Patent and Trademark Attorneys In these methods, a control unit is particularly advantageously used, to which at least the total voltage of the series circuit and optionally the voltage values of individual battery cells or groups of battery cells determined by means of voltmeters can be supplied as input values, and which is connected to the switching elements via at least one control line on its output side. Further input values optionally include the charging or discharging current, and a further output of the control unit is preferably a control line for controlling a charger.
[0047] BRIEF DESCRIPTION OF THE DRAWINGS
[0048] Further features, advantages, and embodiments of the invention will become apparent from the following description of embodiments of a device with reference to the figures. These show:
[0049] Fig. 1 shows a first embodiment of a device according to the invention with a series connection of six battery cells, which can be selectively switched into or out of the series connection via a bypass line and two switching elements assigned to each battery cell;
[0050] Fig. 2 shows a second, simplified embodiment with a series connection of five battery cells, of which three battery cells are permanently connected in series, while the remaining 2 battery cells can be switched into or out of the series connection by means of a bypass line and switching elements;
[0051] Fig. 3 shows a three-dimensional schematic representation of a first parallel arrangement and a second parallel arrangement of battery cells that can be connected in series with it, and their arrangement in the immediate vicinity of a circuit board on which the switching elements and the control unit are placed, with a first variant of connectors; and
[0052] Fig. 4 shows a variant of Fig. 3 with a second variant of connectors.
[0053] FORMS OF EXECUTION OF THE INVENTION
[0054] 102396-WO1 GWI Keller Schneider
[0055] November 4, 2025 Patent and Trademark Attorneys Fig. 1 shows a series circuit 20 arranged between a ground line 10 and a supply line 40, consisting in this example of a total of six battery cells B1, B2, B3, B4, B5 and B6 connected in series, wherein at least some of the battery cells (B1....B6) are sodium-ion battery cells and / or zinc-manganese (Zn-Mn) battery cells and / or zinc-carbon (Zn-C) battery cells.
[0056] The series connection 20 can be interrupted after each of the battery cells B1, B2, B3, B4, B5 and B6 by a switching element S1, S2, S3, S4, S5 and S6.
[0057] Parallel to the series connection 20, a bypass line 30 is provided, which is connected to the series connection 20 by a connecting line after each battery cell B1, B2, B3, B4, B5 and B6.
[0058] In the bypass line 30, a switching element S11, S12, S13, S14, S15 and S16 is provided after each connecting line, by means of which the bypass line 30 can be selectively interrupted section by section.
[0059] Each of the battery cells B1, B2, B3, B4, B5 and B6 is assigned a voltmeter V1, V2, V3, V4, V5 and V6, with which the current voltage of each battery cell can be determined. Additionally, preferably another voltmeter is provided between the ground line 10 and the supply line 40 to determine the current total voltage Vges.
[0060] The voltages of all voltage meters V1, V2, V3, V4, V5, V6 and Vges are fed to a control unit SG via a measuring line ML.
[0061] The control unit SG is connected on its output side via a first control line SL1 to the switching elements S1, S2, S3, S4, S5, and S6, and via a second control line to the switching elements S11, S12, S13, S14, S15, and S16. The control line can be configured as a data bus, so that the control commands are recognized by the respective switching element via an addressing code. Alternatively, each switching element can be connected to the control unit SG via a separate control line.
[0062] 102396-WO1 GWI Keller Schneider
[0063] November 4, 2025 Patent and Trademark Attorneys The control unit SG has a program memory in which a calculation program, depending on a predefinable target total voltage Vges with corresponding lower and upper threshold values and the actual values of the voltage meters V1, V2, V3, V4, V5, V6 and Vges supplied to the control unit via the measuring line ML, switches individual battery cells or groups of battery cells B1, B2, B3, B4, B5 and B6 from or into the series circuit 20 by actuating the switching elements S1, S2, S3, S4, S5 and S6 or S11, S12, S13, S14, S15 and S16 in order to achieve the desired actual total voltage Vges, which corresponds to the nominal voltage range Vn required by the electrical consumers C1, C2 connected to the supply line 40.The nominal voltage range Vn for electrical consumers C1, C2 with a nominal voltage of 12 V is limited, for example, by a lower threshold of 10.5 V and an upper threshold of 15 V.
[0064] The algorithm of the computer program preferably ensures that the state of charge of battery cells B1, B2, B3, B4, B5, and B6 is adjusted by selectively switching them on and off. This allows individual cells to be deliberately kept at a lower state of charge and thus a lower voltage, in order to generate smaller voltage differences during switching or to provide more suitable combinations. The voltage differences between the various battery cells are kept as small as possible so that the switching steps are smaller than the voltage of a single cell. For example, in a series connection of three active battery cells, each with 3.7 V (total V = 11.1 V), switching to four active battery cells, each with 3 V (total V = 12 V), can be performed.
[0065] In the embodiment shown in Figure 1, when using sodium-ion battery cells, the active series connection of all six battery cells B1, B2, B3, B4, B5, and B6 would result in a total voltage Vtotal of 12 V when the battery cells are nearly discharged and have a cell voltage of 2 V. With nearly fully charged battery cells and a cell voltage of 4 V, the total voltage Vtotal would be 24 V, which can be reduced to 12 V by disconnecting three of the six battery cells. As soon as the voltage drops to, for example, 10.5 V due to a decrease in the charge capacity of the three active battery cells, one of the previously active, partially discharged battery cells can then be disconnected from the series connection and replaced by one of the previously passive, still fully charged cells.
[0066] 102396-WO1 GWI Keller Schneider
[0067] November 4, 2025 Patent and trademark attorneys Battery cells are connected in series, so that the total voltage Vges then increases again.
[0068] Table 1 below illustrates an example charging process for the even charging of the six battery cells in eighteen steps, whereby at least part of the
[0069] Battery cells (B1...B6) of sodium-ion battery cells and / or of zinc-manganese (Zn-
[0070] Mn) battery cells and / or zinc-carbon (Zn-C) battery cells are formed: In the first state, shown in the first row of the table, all six cells are largely empty, with cells B1 to B5 having a voltage of 2 V and cell B6 having a voltage of 1.9 V. This results in a total voltage Vtotal of 11.9 V.
[0071] During the subsequent charging in the second row of the table, all six cells are charged to a voltage of 2.5 V, or 2.4 V for cell B6, resulting in a total voltage Vges of 14.9 V, which is just below the upper threshold of the nominal voltage range of 15 V.
[0072] 102396-WO1 GWI Keller Schneider
[0073] November 4, 2025 Patent and Trademark Attorneys To prevent the total voltage Vges from exceeding the upper threshold, the control unit SG now disconnects battery cell B1 from the series circuit 20 by opening switch S1 and simultaneously closing switch S11. This reduces the total voltage Vges to 12.4 V, as shown in the third line of Table 1. In this configuration, cells B2 to B5 are then charged to a cell voltage of 2.9 V each, and cell B6 to a cell voltage of 2.8 V, resulting in a total voltage Vges of 14.4 V, as shown in the fourth line of Table 1.
[0074] According to the fifth line of Table 1, cell B1 is now connected to the series circuit 20 by closing switch S1 and opening switch S11, and simultaneously cell B5 is disconnected by opening switch S5 and closing switch S15. The total voltage Vtotal thus temporarily drops to 14 V.
[0075] In this state, according to the sixth line of Table 1, the battery cells currently actively connected in series (20) are each charged by 0.2 V further, whereby the total voltage Vges rises to 15 V up to the upper threshold of the nominal voltage range.
[0076] By switching according to the seventh row of Table 1, cell B1 is disconnected from the series circuit by opening switch S1 and closing switch S11, and cell B6 is disconnected by opening switch S6 and closing switch S16, so that only cells B2 to B5 are active, resulting in a total voltage Vtotal of 12.2 V. According to the eighth row of Table 1, the cell voltage of cells B2 to B5 is increased by 0.2 V each time, so that the total voltage Vtotal is then 13 V.
[0077] Now, according to the ninth row of Table 1, cell B1 is reactivated in series 20 by opening switch S11 and closing switch S1, while cells B5 and B6 are removed from series 20 by opening switches S5 and S6 and closing switches S15 and S16. In this example, cell B5 is deliberately removed from series 20 earlier to allow for a favorable combination later in row 15. If all cells are equally good, this cell will not be completely full.
[0078] 102396-WO1 GWI Keller Schneider
[0079] November 4, 2025 Patent and Trademark Attorneys According to the tenth line, the cell voltage of the active cells B1 to B4 is increased by 0.2 V each, so that the total voltage Vges increases to 13.2 V.
[0080] According to the eleventh row of Table 1, cell B2 is now disconnected from series 20 by opening switch S2 and closing switch S12, while simultaneously cell B6 is connected to series 20 by closing switch S6 and opening switch S16. The total voltage Vtotal temporarily drops to 12.7 V. Further charging, as described in the twelfth row of Table 1, increases the cell voltage of each active cell by 0.3 V, raising the total voltage Vtotal to 13.9 V.
[0081] Now, according to the thirteenth row of Table 1, cell B2 is connected to series 20 by opening switch S12 and closing switch S2, and cell B4 is disconnected from series 20 by opening switch S4 and closing switch S14. The total voltage Vtotal is thus temporarily reduced to 13.6 V. By further charging the now active cells by 0.3 V each, as per row 14 of Table 1, the total voltage Vtotal increases to 14.4 V.
[0082] According to line fifteen, cell B3 is now disconnected from series 20 by opening switch S3 and closing switch S13, and cell B5 is reconnected to series by opening switch S15 and closing switch S5. The total voltage Vtotal thus temporarily drops to 13.5 V and increases by 0.3 V at a time with further charging, according to line sixteen, to 14.7 V.
[0083] According to line seventeen, cell B2 is disconnected from series 20 by opening switch S2 and closing switch S12, and cell B4 is connected to series 20 by opening switch S14 and closing switch S4. The total voltage Vtotal is then 14.5 V. By further charging by 0.1 V per active cell, the total voltage Vtotal is increased to 14.9 V, according to line seventeen.
[0084] The table explained above in individual steps shows how the state of charge of individual battery cells can be increased uniformly by alternately switching them on and off, without exceeding the permissible total voltage Vges above the upper threshold of the
[0085] 102396-WO1 GWI Keller Schneider
[0086] November 4, 2025 Patent and trademark attorneys to increase the nominal voltage range Vn. The same procedure in reverse order (i.e., in Table 1 from bottom to top, from row 18 to row 1) can be used equally well for a uniform discharge of battery cells B1 to B6.
[0087] It is understood by the expert that the selected numerical values and sequences are only examples and that the uniform charging and discharging of battery cells B1 to B6 can also be achieved by other sequences of switching operations.
[0088] The nominal voltage of 12 V with the associated threshold for the nominal voltage range is also only an example. Using the invention, other series circuits 20 for nominal voltage ranges of, for example, 18 V, 24 V, 36 V or 48 V can also be effectively controlled.
[0089] Another embodiment for a nominal voltage range of 11 V to 13.8 V is illustrated in Table 2 below. Again, the empty fields represent disconnected cells, so the table is self-explanatory, as described in Table 1 above. In this example, according to the sixteenth row, even three battery cells, B1, B4, and B6, are sufficient to generate the minimum required total voltage Vtotal of 11 V.
[0090] Table 2 Example for 11 V - 13.8 V nominal voltage range
[0091] 102396-WO1 GWI Keller Schneider
[0092] November 4, 2025 Patent and Trademark Attorneys | 16 | Plus 0.1 I _ wj _ I _ I _ w] _ I _ w] _ nJ
[0093] Figure 2 shows a simplified alternative to the embodiment according to Figure 1, in which five battery cells B1, B2, B3, B4, B5 are connected in series between a ground line 10 and a supply line 40 in a series circuit 20, wherein at least some of the battery cells (B1...B5) are sodium-ion battery cells and / or zinc-manganese (Zn-Mn) battery cells and / or zinc-carbon (Zn-C) battery cells. The first three battery cells B1, B2, and B3 are permanently arranged in the series circuit 20, while the other battery cells B4 and B5 can be selectively connected to or from the series circuit 20 via switching elements S4 and S5 and via a bypass line 30 and switching elements S14 and S15 located therein.
[0094] In this case, the control unit SG receives measured values from the voltmeters V1-3, V4, V5, and Vges, and preferably also the current values of the individual battery cells. On the output side, a control line SL1 controls the switching elements S4 and S5, and a control line SL2 controls the switching elements S14 and S15. The control lines SL1 and SL2 can be configured as a data bus, so that the control commands are recognized by the respective switching elements S4, S5, S14, and S15 via an addressing code. Alternatively, each switching element S4, S5, S14, and S15 can be connected to the control unit SG via a separate control line.
[0095] The simplified embodiment shown in Figure 2 assumes that battery cells B1, B2, and B3 will always be required to generate the desired total voltage Vges, while, as the charge level of these battery cells decreases, the additional battery cells B4 and / or B5 can be selectively connected. Corresponding to the shorter connection time, the capacity of battery cells B4 and B5 can also be selected to be correspondingly smaller than the capacity of B1, B2, and B3.
[0096] As can be seen from Figure 3, preferably many battery cells B1 to B6 are connected in parallel to one another and selectively switchable into a series connection 20 in the manner described above by means of the switching elements S1 - S6 and S11 - S16, arranged directly on and / or under a circuit board P on which the switching elements S1 - S6 and S11 - S16, the ground line 10, the lines for the series connection 20, the bypass line 30, the positive-
[0097] 102396-WO1 GWI Keller Schneider
[0098] November 4, 2025 Patent and trademark attorneys Line 40, the control lines SL1, SL2 and SL3, the current measuring paths, the voltage meters V1 - V6 and Vges with the measuring lines ML, the connections for the consumers C1 and C2 and the charger L as well as the control unit SG are integrated.
[0099] As can be seen from Figures 3 and 4, the parallel-connected battery cell packs B1 to B6 are connected away from the circuit board P by means of connectors 50, which preferably also provide mechanical support for the battery cell packs B1 to B6 relative to the circuit board P. The battery cell packs B1 to B6 are contacted towards the circuit board P by means of connectors 60 or spring contacts 70, which are arranged in the immediate vicinity of the switching elements S1 - S6 and S11 - S16 located on the circuit board P.
[0100] For the sake of simplicity, Figures 3 and 4 show only the first battery cell packs B1 and the second battery cell packs B2 with the switching elements S1 and S2. It is understood by those skilled in the art that further battery cell packs B3 to B6 can be connected to battery cell packs B1 and B2 on the same side of the circuit board P and on the opposite side. The number of three parallel-connected battery cells B1 or B2 is also only exemplary and kept small for the sake of simplicity. Depending on the desired total capacity, the parallel connection of battery cell packs B1 and B2 can include significantly more than three battery cells.
[0101] The number of six or five battery cells (packages) chosen in the embodiments according to Figures 1 and 2 is also only exemplary and can be significantly higher in practice, especially with a higher nominal voltage of the consumers CI, C2 of 18V, 24V, 36V or 48V.
[0102] The connectors 50 and / or 60 can preferably be connected to the battery cell packs B1 to B6 by means of a spring connection in order to enable a secure electrical connection and at the same time to compensate for tolerances in case of different lengths of the battery cells.
[0103] As already mentioned at the outset, the device and method according to the invention can be used to implement a discharge management system for an equal-
[0104] 102396-WO1 GWI Keller Schneider
[0105] November 4, 2025 Patent and trademark attorneys to provide moderate discharge or charge management for charging multiple battery cells connected in series. In any case, the C-rate must be taken into account so that the maximum charge or discharge current can still be provided, especially with smaller B4 and B5 cells.
[0106] 102396-WO1 GWI Keller Schneider
[0107] November 4, 2025 Patent and Trademark Attorneys REFERENCE MARK LIST
[0108] 10 Ground wire
[0109] 20 series connection (multiple battery cells B1 - B6)
[0110] 30 Bypass line
[0111] 40 Plus line
[0112] 50 connectors
[0113] 60 connectors
[0114] 70 contacts
[0115] B1 - B6 battery cells (20 connected in series)
[0116] C1, C2 Consumers
[0117] Total flow (out of 20)
[0118] L charger
[0119] P board
[0120] 51 - S6 switching element (for interrupting the series circuit 20)
[0121] S11 - S16 switching element (for bypassing one battery cell each B1 - B6)
[0122] SG control unit
[0123] SL1 Control line 1 (for controlling the switching elements S1 - S6)
[0124] SL2 Control line 2 (for controlling the switching elements S11 - S16)
[0125] SL3 Control line 3 (for controlling the charger L)
[0126] ML measuring line
[0127] V1 - V6 Voltage meter of the individual battery cells B1 - B6
[0128] Total voltage (between positive lead 40 and ground lead 10)
[0129] VL charging voltage
[0130] Vn nominal voltage range (of consumers C1, C2)
[0131] 102396-WO1 GWI Keller Schneider
[0132] November 4, 2025 Patent and Trademark Attorneys
Claims
REQUIREMENTS 1. Device for supplying voltage to at least one load (C1, C2) operable within a nominal electrical voltage range (Vn) by means of at least one series circuit (20) with several battery cells (B1....B6) connected in series, wherein all battery cells (B1....B6) connected in series of a series circuit (20) in a fully charged state generate a total voltage (Vges) which is above the nominal voltage range (Vn) of the at least one load (C1, C2), and wherein individual battery cells (B1....B6) or groups of battery cells (B1....B6) can be switched into or out of the series circuit (20) by means of at least one bypass line (30) and several switching elements (S1....S6; S11 S16) in order to bring the total voltage (Vges) of the series circuit (20) into conformity with the nominal voltage range (Vn) of the at least one load (C1, C2), wherein at least a part of the battery cells (B1....B6) is formed by sodium-ion battery cells and / or zinc-manganese (Zn-Mn) battery cells and / or zinc-carbon (Zn-C) battery cells.
2. Device according to claim 1, characterized in that the voltage of the individual battery cells (B1....B6) or groups of battery cells (B1....B6) is measured by means of voltmeters (V1.... V6).
3. Device according to claim 2, characterized by a control unit (SG) to which the total voltage (Vges) and / or the values of the individual voltage meters (V1.... V6) and / or the total current (Iges) and / or the partial currents (I 1....I6) generated by the battery cells (B1....B6) can be supplied as input values via at least one measuring line (ML).
4. Device according to claim 3, characterized in that the control unit (SG) is connected to the switching elements (S1.... S6; S11 S16) or a charger (L) via at least one control line (SL1, SL2; SL3) for their control. 102396-WO1 GWI Keller Schneider November 4, 2025 Patent and Trademark Attorneys 5. Device according to one of the preceding claims, characterized in that individual battery cells (B1....B6) or groups of battery cells (B1....B6) are permanently arranged in series (20).
6. Device according to one of the preceding claims, characterized in that the switching elements (S1.... S6; S11 S16) are formed by a relay, a transistor or one or more MOSFETs.
7. Device according to at least one of the preceding claims, characterized in that the switching elements (S1.... S6; S11 S16) and / or the battery cells (B1....B6) and / or the control unit (SG) are arranged on or at least near a circuit board (P) and are in direct contact with its conductor tracks via connectors (50; 60) or, in particular, spring contacts (70).
8. Method for controlling the total electrical voltage (Vtotal) of a series connection (20) of series-connected battery cells (B1...B6) to the nominal voltage range (Vn) of at least one load (C1, C2), in particular using a device according to one of the preceding claims, wherein at least some of the battery cells (B1...B6) are sodium-ion battery cells and / or zinc-manganese (Zn-Mn) battery cells and / or zinc-carbon (Zn-C) battery cells, characterized by the following method steps - Measuring the total voltage (Vges) and / or the individual voltage values (V1.... V6) of the battery cells (B1....B6) and / or the total current (Iges) and / or the partial currents generated by the battery cells (B1....B6) and supplying these measured values to a control unit (SG), - Program-controlled coupling of at least one battery cell (B1....B6) from the series connection (20) by means of at least one switching element (S1.... S6; S11 S16) arranged in the series connection (20) and / or in a bypass line (30) arranged in parallel to the series connection (20) by the control unit (SG). 102396-WO1 GWI Keller Schneider November 4, 2025 Patent and Trademark Attorneys 9. Method for controlling a charging voltage of several battery cells (B1....B6) connected in series in at least one series connection (20), wherein at least some of the battery cells (B1....B6) are sodium-ion battery cells and / or zinc-manganese (Zn-Mn) battery cells and / or zinc-carbon (Zn-C) battery cells, characterized by the following method steps - Measuring the total voltage (Vges) and / or the individual voltage values (V1.... V6) of the battery cells (B1....B6) and / or the total current (Iges) and / or the partial currents (11....16) generated by the battery cells (B1....B6) and supplying these measured values to a control unit (SG), - Program-controlled coupling of at least one battery cell (B1....B6) from the series connection (20) by means of at least one switching element (S1.... S6; S11 S16) arranged in the series connection (20) and / or in a bypass line (30) arranged in parallel to the series connection (20) by the control unit (SG). 102396-WO1 GWI Keller Schneider November 4, 2025 Patent and Trademark Attorneys