BATTERY CELL FILLING DEVICE AND METHOD

Description

[0001] The invention relates to a fully automatic filling device for battery cells, in particular lead-acid accumulator cells. Furthermore, the invention relates to a method for filling battery cells, in particular lead-acid accumulator cells, using a fully automatic filling device according to the invention.

[0002] In principle, filling devices for battery cells are known from the prior art. They can be used to fill battery cell types that require a liquid electrolyte, such as an aqueous electrolyte solution, with electrolyte.

[0003] With known devices and processes, it has been standard practice to produce the required electrolyte solution in appropriate systems using a batch process and then either store it or feed it to a separate dosing system in which the battery cells are subsequently filled with electrolyte solution.

[0004] This process has proven to be comparatively inflexible and requires intensive planning. Depending on the type and size of the battery cell, electrolyte solutions with different qualitative and / or quantitative adjustments are required, all of which, according to existing methods, must be pre-produced and, if necessary, stored awaiting later use. A further disadvantage is that the quality of electrolyte solutions decreases with increasing storage time.

[0005] Furthermore, it is not possible to correct any errors in the production of the electrolyte batch, so that inferior electrolyte solution must be discarded.

[0006] There is therefore a vital economic interest in eliminating the aforementioned disadvantages and making the manufacturing and dosing processes more flexible and economical.

[0007] The invention is therefore based on TaskThe aim is to eliminate the disadvantages known from the state of the art.

[0008] To SolutionTo achieve this aim, the invention proposes a fully automatic filling device for filling battery cells, in particular lead-acid accumulator cells, with electrolyte solution, in particular an electrolyte solution containing sulfuric acid, comprising a mixing unit, in particular a mixing cylinder, for producing electrolyte solution from a plurality of components, a dosing unit for introducing the electrolyte solution into the battery cell, the dosing unit being fluidly connected to the mixing unit and being arranged downstream of the electrolyte solution in the flow direction, and comprising a control / regulation unit for the fully automated control and regulation of at least the mixing unit and the dosing unit, comprising a digital data processing device, a digital data memory, and sensors and actuators connected to the mixing unit and / or the dosing unit for data transmission purposes.

[0009] The fully automatic filling device according to the invention enables the production and filling of battery cells in a coherent, continuous process using a single device. In contrast to the prior art, the required electrolyte solution is prepared from the required reactants in the mixing unit immediately before filling the battery cell. Complex storage of the electrolyte solution in large quantities and its transport from the mixing system to the dosing system are completely eliminated. Only the starting materials for the electrolyte solution need to be provided. Furthermore, the device according to the invention allows for flexible control of the electrolyte composition via the control / regulation unit and the adjustment of the concentrations of the individual components depending on predeterminable target values. This is a decisive advantage, particularly with regard to lead-acid battery cells.This is because the acid density (mass concentration in g / cm3) can be kept constant or changed as needed by the control unit, even during dosing into the battery cell. For this purpose, the control unit is preferably connected via sensors to the dosing unit on the one hand and the mixing unit on the other.

[0010] The device according to the invention is preferably intended for filling high-performance batteries formed from lead-acid accumulator cells with electrolyte solution. A battery block is typically formed from six battery cells. The device according to the invention is preferably designed to fill the six cells of a battery block simultaneously. For this purpose, the battery cells combined to form battery blocks are fed to the device according to the invention, filled, and removed block by block. By appropriate scaling, however, it is also possible to fill single-cell batteries or battery blocks with up to 12 battery cells simultaneously. For transporting the battery blocks, the device according to the invention preferably has automatically controllable conveying means, in particular conveyor belts.

[0011] The dosing unit according to the invention serves to introduce the electrolyte solution previously prepared in the mixing unit into the battery cells. If the battery cells to be filled are grouped together to form battery blocks, the introduction can either be staggered in any predefined order. Alternatively, simultaneous filling of all battery cells of the battery block is preferably possible. In this regard, the dosing unit can have a robot-supported, movable nozzle head that approaches the battery cells in the predefined order and fills them one after the other. Alternatively, a number of nozzle heads corresponding to the number of battery cells to be filled simultaneously can be provided. A combination is also conceivable in which, for example, two nozzle heads are provided, each of which approaches a predefined number of battery cells to introduce the electrolyte solution.

[0012] According to a preferred feature of the invention, the mixing unit is designed as a mixing cylinder. This results in advantageous flow conditions in the cylindrical interior of the mixing unit, which ensure improved mixing of the electrolyte solution. The mixing unit is preferably connected to the control / regulation unit via sensors and control technology. Furthermore, it is designed to allow the production of electrolyte solution at extremely low temperatures between -25 °C and 0 °C. The electrolyte solution produced in the mixing unit is preferably suitable for use in a lead-acid storage battery. This electrolyte solution is composed in particular of sulfuric acid, water, and silica. The concentration of the components can be freely adjusted and regulated using the control / regulation unit depending on the desired acid density.

[0013] According to a preferred feature of the invention, the device comprises a reservoir for storing electrolyte solution, which is fluidically connected to the mixing cylinder and / or the dosing unit. The reservoir serves the purpose of holding a certain excess of electrolyte solution and keeping it available for later use, in particular for filling the next battery block in the production process or for compensating for differences in the fill level between cells of a battery block. The reservoir is therefore not comparable to the storage tanks known from the prior art, which, in contrast, store electrolyte solution for many production batches of battery blocks. The reservoir according to the invention is preferably designed to store electrolyte solution at temperatures of up to -25°C.

[0014] According to the invention, a vibration unit is provided for generating high-frequency mechanical vibrations in the electrolyte solution. The vibration unit can preferably be designed as a vibrating plate on which the battery block is arranged. According to this embodiment, the electrolyte solution is thus indirectly set into high-frequency vibration via the battery block arranged on the vibrating plate. According to an alternative embodiment of the vibration unit, this has ultrasonic probes, one of which can be inserted into a battery cell filled with electrolyte solution. In this way, the electrolyte solution can be directly set into vibration by the ultrasonic probes. Regardless of the alternative used, it has been shown that the transmission of vibrations to the electrolyte solution improves its penetration into parts of the battery cell, in particular separators and electrodes.In particular, the electrolyte penetrates deeper into the pore structure of separators and electrodes. The penetration process is also advantageously accelerated by the high-frequency vibration of the electrolyte solution. The vibration unit is preferably designed to cause the electrolyte solution to vibrate at high frequencies during and / or after introduction into the battery. In particular, to accelerate the process, the vibration unit can be activated as soon as a predefined fill level is reached in the battery cells, but the filling process is not yet complete.

[0015] According to a preferred feature of the invention, a pressure generating unit is provided for setting a negative and / or positive pressure in the battery cell. The pressure generating unit is preferably designed to allow negative pressure, in particular a vacuum, and positive pressure to act on the battery cell in alternating time. This advantageously further improves the penetration depth and speed of the electrolyte solution into parts of the battery cell, such as separators and electrodes. The pressure generating unit preferably comprises a diaphragm pump.

[0016] According to a preferred feature of the invention, the device comprises a housing in which preferably all components of the device, at least the mixing unit and dosing unit, are arranged. In particular, it can be provided that the storage container, control / regulation unit, pressure generation unit, and / or vibration unit are also arranged in the housing.

[0017] According to a further feature of the invention, the control / regulation unit is designed to continuously compare actual values ​​with a retrievably stored nominal value and, if at least one actual value falls below and / or exceeds the nominal value, to initiate control measures to adjust the actual values ​​to the nominal value. In particular, the control / regulation unit is capable of sensor-based detection of actual values ​​with regard to concentrations, temperature and / or weight and comparing them with nominal values ​​stored retrievably in a digital data memory. In the event of a deviation from the nominal value within predeterminable tolerances, the control / regulation unit controls the mixing unit and / or the dosing unit in such a way that the measured variable associated with the actual value is adjusted to the nominal value in terms of value.For example, the acid density of the electrolyte solution is measured by a sensor using a flow measurement in the dosing unit. This is then compared with a stored target value. If a deviation exceeds or falls below the tolerance range, the control unit activates the mixing unit to adjust the acid density back to the target value.

[0018] The control / regulation unit has sensors for recording actual values, a digital data storage device for retrievably storing target values, a data processing device for performing a target / actual comparison, and a control connection with corresponding actuators for influencing the variables to be controlled, such as concentration, temperature, and / or fill volume. Actuators within the meaning of the invention include, for example, valves, agitators, and the like.

[0019] To SolutionIn order to achieve this object, the invention further proposes a method for the fully automatic filling of battery cells by means of a fully automatic filling device according to the invention, in which an electrolyte solution is produced from a plurality of components in a mixing unit, the concentrations of the individual components being automatically adjusted to predeterminable values ​​by means of the control / regulation unit, and in which the electrolyte solution is introduced into the battery cell by means of a dosing unit, the filling quantity of the electrolyte solution in the battery cell being automatically adjusted to a predeterminable value by means of the control / regulation unit.

[0020] The method according to the invention, in conjunction with the device according to the invention, allows the production and filling of battery cells in a coherent, continuous process. In contrast to the prior art, the required electrolyte solution is produced from the required reactants in the mixing unit immediately before filling the battery cell. The complex storage of large quantities of electrolyte solution and its transport from the mixing system to the dosing system are completely eliminated. Only the starting materials for the electrolyte solution need to be provided. Furthermore, the device according to the invention allows for flexible control of the electrolyte composition via the control / regulation unit and the adjustment of the concentrations of the individual components depending on predeterminable target values. This is a decisive advantage, particularly with regard to lead-acid battery cells.This is because the acid density can be kept constant or changed as required by the control / regulation unit, even during dosing into the battery cell.

[0021] The invention is explained below using an exemplary embodiment. Fig.1 a fully automatic filling device according to the invention.

[0022] Figure 1 shows a fully automatic filling device 1 according to the invention. The filling device 1 is used in this case for filling lead-acid batteries with electrolyte solution having a predeterminable acid density. The batteries to be filled consist of a battery block of six battery cells. Each battery cell is already equipped with separators and electrodes at the time of filling.

[0023] The filling device 1 has a housing 2. Arranged in the housing 2 are a mixing unit 3, a dosing unit 4, a control / regulation unit (not shown), a conveyor belt 5, a vibration unit (not shown), and a pressure generation unit (not shown).

[0024] In the mixing unit 3, which in this case comprises a plurality of mixing cylinders 6, the electrolyte solution is prepared from sulfuric acid, water, and silica. After preparation, the electrolyte solution is directly fed to the dosing unit 4, by means of which the electrolyte solution is introduced into the battery cells.

[0025] In this case, a conveyor belt 5 is used to transport the battery cells to, through and away.

[0026] In this case, the acid density and fill level can be measured by sensors and adjusted or regulated to a predefined target value by means of the control / regulation unit (not shown) through a target / actual value comparison and the subsequent activation of corresponding actuators. The actual value is measured by means of corresponding sensors, which are located in particular in the dosing unit 4 and / or the mixing unit 3.

[0027] The pressure generation unit (not shown) is used to apply a vacuum and / or overpressure to the battery cell. This improves the electrolyte absorption of the separators and electrodes arranged in the battery cells.

[0028] The device 1 according to the invention further comprises a vibration unit in the form of a vibrating plate integrated into the conveyor belt. The vibration unit serves to improve electrolyte uptake by separators and electrodes arranged in the battery cells.

[0029] In principle, all work steps in device 1 are fully automated. The individual components are controlled by the control / regulation unit. For this purpose, the control / regulation unit has a data processing unit that controls the device components based on a control program executed on the data processing unit.

[0030] In addition, device 1 features a fully automated self-cleaning function, which is also controlled by the control unit. This significantly improves work safety. Reference symbol

[0031] 1Filling device 2Housing 3Mixing unit 4Dosing unit 5Conveyor belt 6Mixing cylinder

Claims

1. Fully automatic filling device for filling battery cells, in particular lead-acid accumulator cells, with an electrolyte solution, in particular a sulfuric electrolyte solution, the device comprising a. a mixing unit, in particular a mixing cylinder, for preparing an electrolyte solution from several components at temperatures between -25°C and 0°C; b. a dosing unit for introducing the electrolyte solution into the battery cell, wherein the dosing unit is fluidically connected to the mixing unit and arranged downstream thereof in the direction of flow of the electrolyte solution; c. a controlling / regulating unit for fully automatic control and regulation of at least the mixing unit and the dosing unit, the controlling / regulating unit comprising a digital data processing means, a digital data storage as well as sensors and actuators connected to the mixing unit and / or dosing unit in data transmitting manner, characterized by a vibration unit for generating high-frequency vibrations within the electrolyte solution.

2. Filling device according to claim 1, characterized by a reservoir fluidically connected to the mixing cylinder and / or dosing unit, for storage of the electrolyte solution at temperatures of up to -25°C.

3. Filling device according to one of the claims 1 or 2, characterized by a conveyor means, in particular a conveyor belt, for feeding the battery cells to the dosing unit.

4. Filling device according to claim 1, characterized in that the vibration unit is designed to oscillate the electrolyte solution at a high frequency during and / or after the introduction into a battery cell.

5. Filling device according to any of the preceding claims, characterized by a pressure generating device for setting an under- and / or overpressure in the battery cell.

6. Filling device according to any of the preceding claims, characterized in that the controlling / regulating unit is designed to continuously compare actual values with a retrievable stored setpoint and when at least one actual value falls below and / or exceeds the setpoint, to effect control-related measures in order to adjust the actual values to the setpoint.

7. Filling device according to any of the preceding claims, characterized by a housing in which at least the mixing unit and the dosing unit are accommodated.

8. Method for fully automatically filling battery cells using of a fully automatic filling device according to any of the preceding claims, in which method an electrolyte solution from several components is prepared in a mixing unit, wherein the concentrations of the individual components are set by means of the control / regulating unit automatically to pre-definable values, and in which the electrolyte solution is introduced by means of the dosing unit into the battery cells, wherein the filling amount of the electrolyte in the battery cells is set is an automated manner by means of the control / regulating unit to a pre-definable value.

9. Method according to claim 8, characterized in that the electrolyte solution is introduced into the battery cells under application of a vacuum and / or an overpressure.

10. Method according to any of claims 8 or 9, characterized in that the electrolyte solution in the battery cells is oscillated at a high frequency by means of vibration.

11. Method according to any of claims 8 to 10, wherein the electrolyte solution in the mixing unit is prepared within a temperature range between -15°C and 0°C.

12. Method according to any of claims 8 to 11, characterized in that for an automated setting of the concentration of the components in the electrolyte solution and / or the filling level of the electrolyte in the battery cells, actual values are continuously compared with retrievable stored setpoints and when at least one actual value falls below and / or exceeds the setpoint, control-related measures are effected on behalf of the control / regulation unit in order to adjust the actual values to the setpoint.