Pre-aging method for pre-aging a battery, and test method for testing sets of batteries

Abstract

The present invention relates to a pre-aging method (10) and to a pre-aging system (20) for pre-aging a battery (2) to a predetermined aging condition, a test method (30) and a test system (40) for testing sets of batteries according to a predetermined test plan, and a computer program product.

Description

[0001] Pre-aging procedures for pre-aging a battery and test procedures for testing battery packs

[0002] The present invention relates to a pre-aging method for pre-aging a battery to a predetermined aging state, a test method for testing battery sets according to a predetermined test plan, a computer program product, a pre-aging system for pre-aging a battery to a predetermined aging state and a test system for testing battery sets according to a predetermined test plan.

[0003] The aging behavior of newly developed batteries is of great interest. The usual method for determining aging behavior is to conduct aging measurement tests with artificial load profiles. The load profiles are defined by a sequence of charge / discharge cycles, followed by rest periods and a capacity and power test, as well as additional tests if necessary. The parameters of the artificial profiles can be varied to obtain information about aging behavior under different conditions.

[0004] The state of the art is to conduct the aging measurement test based on DOE (Design of Experiment) to obtain maximum information from the number of batteries used. A specific set of cycle parameters is applied to each individual battery, and the cycle begins with a new state until a predefined state of health (SOH) of, for example, 75% is reached.

[0005] With this method, the remaining capacity decreases over time depending on the selected load profile parameters. The resulting time to reach the desired SOH depends heavily on the selected load profile. This can lead to some batteries reaching the end of their service life very early, while others fail to reach the desired SOH value. A battery only provides information about one set of load profile parameters.

[0006] In addition to the achievement of different SOH values, the long duration of the known test procedure is a disadvantage. For example, to test batteries in an SOH range of 100% to 80% battery capacity, it is quite possible that they will have to undergo 1,000 or more cycles. The associated long durations are unavoidable when limiting the test to a single set of cycle parameters, since – in the case of cycle parameters that moderately influence aging – the aging of the battery or the achievement of an SOH of 0 can take a long time.

[0007] The object of the present invention is to at least partially remedy the disadvantages described above. In particular, the object of the present invention is to provide methods and systems that facilitate, and especially accelerate, battery testing in a cost-effective and simple manner.

[0008] The above object is achieved by a pre-aging method having the features of claim 1, a test method having the features of claim 9, a computer program product having the features of claim 13, a pre-aging system having the features of claim 14 and a test system having the features of claim 15. Further features and details of the invention emerge from the subclaims, the description and the drawings. Features and details described in connection with the pre-aging method according to the invention naturally also apply in connection with the test method according to the invention, the computer program product according to the invention, the pre-aging system according to the invention and the test system according to the invention and vice versa, so that with regard to the disclosure of the individual aspects of the invention, reference is or can always be made reciprocal.

[0009] According to the invention, a pre-aging method is provided for pre-aging at least one battery to a predetermined aging state. The pre-aging method according to the invention comprises the following steps:

[0010] - Specifying the ageing state of the battery to be achieved,

[0011] - Selecting at least one aging profile from a plurality of different aging profiles, wherein each of the aging profiles specifies at least one charging and / or discharging process with predefined aging parameters for the battery,

[0012] - Applying the previously selected at least one aging profile to the battery,

[0013] - Selecting at least one further aging profile from the plurality of different aging profiles, wherein the further aging profile differs in at least one of the predefined aging parameters from the previously selected aging profile applied to the battery,

[0014] - Applying the previously selected at least one further aging profile to the battery until the specified aging state of the battery is reached.

[0015] Compared to known aging processes, in which the same cycle is always applied to a battery, the pre-aging process according to the invention enables customized battery aging to a desired aging state. This is particularly useful when multiple batteries are aged in parallel. In this case, the pre-aging process according to the invention has the advantage that multiple batteries can be aged relatively evenly in terms of the required time due to the different aging profiles.

[0016] A particular application of the pre-aging process according to the invention is with regard to a preferably subsequent test method according to the invention, as explained in more detail below. For this purpose, batteries pre-aged with the pre-aging process according to the invention are advantageously used in order to utilize the advantages of rapid and uniform battery aging.

[0017] Nevertheless, it is also possible to use the pre-aging process as such as a test procedure, in which information about battery aging can be obtained through the application of aging profiles. In this respect, the pre-aging process can also be designed to obtain aging information for the various aging profiles. The aging state can be described by the so-called SOH (State of Health). Advantageously, the aging state can be specified solely by the SOH. The SOH is a measure of the battery's available capacity at the respective aging state—along with other influencing variables. It can be specified, in particular, as an indication of the available residual capacity of the battery in relation to the original battery capacity or the battery's design capacity.Another SOH influencing factor relevant for operation is the (relative) change in internal resistance with progressive battery aging (generally an increase in internal resistance over aging).

[0018] It was discovered through appropriate experiments that the SOH adequately describes the aging state of the battery. It was found that the SOH depends only insignificantly on the previous stress on the battery when operating within certain cell operating parameters (including, but not limited to, charge / discharge current, cell voltage limits, temperature). Instead, the aging state can be adequately described by the SOH, and the battery aging history can be neglected when operating within cell chemistry-dependent parameters. In this case, a single battery cell, for example, can be used as the battery. However, several interconnected battery cells or battery modules of a battery pack can also be used. And of course, it is also possible to use a battery pack as the battery, so that the entire battery pack with all its battery cells is pre-aged.The battery pack can, in particular, be a traction battery for an electric motor vehicle. With a cost-intensive traction battery, aging over the long service life of the vehicle plays a particularly important role, which must be investigated through tests before a battery is used in a vehicle.

[0019] In this context, an aging profile is understood to mean a specification of at least one charging and / or discharging process for the battery. An aging profile preferably comprises the specification of several charging and / or discharging processes defined on the basis of predefined aging parameters, in particular several charging and discharging cycles. For example, an aging profile can define 2 to 300, 4 to 200, 10 to 150, or the like, predefined charging and discharging cycles based on aging parameters. An aging profile thus specifies charging / discharging cycles for the battery, which are always applied to the battery under the same aging parameters for a predetermined number of cycles. The aging parameters are to be understood as parameters that can be adjusted and varied during the charging / discharging cycles and that influence the aging of the battery.These may in particular be external environmental parameters and / or electrical operating parameters of the battery.

[0020] In the pre-aging method according to the invention, at least two different aging profiles are provided, which are selected and applied to the battery. To differentiate between the aging profiles, the at least one second aging profile is referred to as at least one further aging profile. It differs from the other or all other aging profiles in one or more aging parameters. In order to decide when to switch between the aging profiles, a further step of determining an intermediate aging state can be provided. The intermediate aging state can also be compared with the predetermined aging state. It is also possible to predefine the aging parameters of the further aging profile depending on an intermediate aging state, in particular a comparison of the intermediate aging state with the predetermined aging state.

[0021] The application of the at least one further aging profile continues until the predefined termination criterion of the pre-aging process is met. The termination criterion is that the previously specified aging state is reached. The result is a battery that has been pre-aged quickly and evenly to the specified aging state and can now be used, in particular for the aforementioned test method according to the invention.

[0022] It is not necessary, but possible, for all method steps of the method according to the invention to be carried out in the order specified by their mention. Individual method steps can also be carried out in a different order or simultaneously. For example, the desired aging state of the battery can be specified even after the aging profile has been selected, or the desired aging state can be adjusted during the process as needed.

[0023] It is advantageous if, until the battery reaches its predetermined ageing state, further ageing profiles are selected from the multitude of different ageing profiles and applied to the battery, wherein the further ageing profiles differ from the previously selected and applied ageing profile in at least one or more of the predefined ageing parameters. The further ageing profiles can also differ from several or all of the previously selected and applied ageing profiles in at least one or more of the predefined ageing parameters. Thus, by applying even more different ageing profiles, an even more uniform and faster pre-ageing of the battery is achieved. In addition, more information about the ageing behavior can be obtained than with a fixed ageing profile.

[0024] It is further advantageous if at least one of the selected aging profiles is configured to age the battery at a first rate, and at least one other of the selected aging profiles is configured to age the battery at a second rate different from the first rate. Thus, aging is typically assumed to be faster under very intense loads than under low loads. For example, the first rate can be a typically slow aging rate with a low charging and / or discharging current, while the second rate can be a fast aging rate with a typically very high charging and / or discharging current.This ensures the aforementioned homogenization because not only are aging parameters changed between the aging profiles that ensure a similar and equally rapid aging, but aging profiles that age at different rates are actually applied to the battery.

[0025] Advantageously, the predetermined aging parameters are at least two of a temperature, a mechanical pressure, a charging current, a discharging current, a state of charge, in particular a delta state of charge, and a pulse frequency. Very particularly, they can also be at least three or more or all of the aforementioned. The environment of the battery can be influenced by the temperature and the mechanical pressure, so that these aging parameters can be regarded as external environmental parameters that can influence the aging of the battery. The remaining parameters are electrical operating parameters of the battery that can be adjusted during charging and / or discharging. The state of charge, for example, can be used as an aging parameter to specify how strongly the battery is charged and discharged between charge / discharge cycles. The state of charge can, for example, be predefined absolutely or relatively.Different predefinitions are also possible with regard to the other aging parameters, for example with regard to the discharge current and charging current, where it is possible, for example, to predefine the peak current and / or the average current.

[0026] It is advantageous if the specified aging parameters in the aging profiles lie within a specified parameter range. This parameter range can be restricted, particularly with regard to the battery design. This prevents the battery from being operated outside its design limits, for example, at temperatures below -40°C when the battery is only designed for a maximum of -40°C. This ensures that pre-aging does not cause damage to the battery, which may only become apparent later and render the pre-aged battery unusable, especially testable, as would be possible under proper real-world conditions.

[0027] Furthermore, it is preferred if the specified aging state is in the range of 95% to 70%, in particular 90% to 75%, residual capacity measured against the battery's design capacity. For example, SOHs of 95%, 90%, 85%, 80%, 75%, and / or 70% can be considered.

[0028] It is particularly preferred if several batteries are pre-aged in parallel. Advantageously, the predetermined aging state is the same for all batteries. For this purpose, the batteries can be located, for example, in a battery arrangement with a parallel connection of the batteries and a voltage source for charging the batteries and an electrical consumer for discharging the batteries. The batteries can preferably be identical in construction, but can also differ from one another, for example with regard to cell chemistry, structure, number of cells, etc. The batteries advantageously have the same battery capacity of 100% of the design capacity. By means of the pre-aging method according to the invention, all batteries can be brought to essentially the same aging state after an approximately equal period of time, because the different aging profiles used enable the aging of the batteries to be evened out.

[0029] The respective aging profiles can preferably be selected differently for all of the batteries pre-aged in parallel. As already mentioned, this also allows for testing the batteries, as different aging profiles are used, allowing more information to be gathered about the aging of the batteries, especially of the same type. Alternatively, the same aging profiles can be selected and applied for the respective batteries to ensure the most uniform aging possible.

[0030] It is also advantageous that, in order to achieve the specified aging state of all batteries, the aging profiles for the batteries are selected taking into account the interim aging states of the other batteries. As previously mentioned, an interim aging state can be determined or monitored, particularly in relation to the specified aging state. However, with multiple batteries, this can be used not only as feedback for selecting the aging profile of the battery with the interim aging state, but also for the other batteries. For example, it can be determined that one battery is aging comparatively faster than the others because the interim aging state of this battery is higher than that of the other batteries.An aging profile can then be selected for the other batteries which causes faster aging than the battery with the already high intermediate aging state, in order to equalize the batteries with regard to their intermediate aging states. By comparing the intermediate aging states in this way and feeding this feedback back to the pre-aging process for selecting the respective aging profiles, it is possible to keep the batteries within a predetermined battery capacity corridor which the batteries do not leave together during the pre-aging process. This enables active control of the pre-aging of several batteries based on the aging profiles. Ageing all batteries at the same average rate, i.e. implementing an average aging rate, is particularly advantageous.A further and crucial advantage is the ability to measure as many different combinations of aging parameters as possible at each current aging level (SOH). The information obtained from these measurements can be linked. For this purpose, a model can be created from the previously measured data regarding the relationship between the aging parameters and aging. Using this model, new aging parameter combinations can then be selected where little information is available, and, in particular, a specified aging rate corridor can be maintained.

[0031] The present invention also provides a test method for testing battery packs according to a predetermined test plan. The test method comprises the following steps:

[0032] - Providing a first battery set with at least one first battery having a first battery capacity,

[0033] - Providing at least one second battery set with at least one second battery having a second battery capacity different from the first battery capacity,

[0034] - Specifying the test plan for testing the battery sets, whereby the test plan specifies charging and / or discharging processes with predefined test parameters for the battery sets, and

[0035] - parallel testing of the two battery sets according to the specified test plan.

[0036] The test method according to the invention thus allows for a significant acceleration of testing batteries, in particular battery sets, according to a predetermined test plan. This is achieved by providing and testing batteries with different battery capacities. This allows batteries to be tested within a specific range of an aging state, in particular the SOH range, for example from 100% to 80%, without actually testing all batteries over the required number of cycles from 100% design capacity to 80% according to the test plan. The test plan can, in particular, be a DOE test plan. The batteries of the individual battery sets can, in particular, be identical batteries, i.e., in particular, with the same cell chemistry, the same cell structure, and / or the same design capacity.This allows a battery of a specific type to be tested with a comprehensive sample, allowing for inter-battery variability in the test procedure. Different test parameters can also be applied to different batteries, allowing different information regarding battery aging to be obtained during the aging of each battery.

[0037] Each of the at least two battery sets therefore preferably comprises several batteries, i.e., at least two, three, or more batteries, for example, two to ten or three to six batteries. This allows for a larger sample size for testing and thus more valid test results.

[0038] Battery capacity is understood, in particular, to mean the maximum capacity of a battery, which, as explained above, can be specified in relation to its design capacity. In particular, the battery capacities of the at least one first battery and the at least one second battery are residual capacities, wherein the batteries originally had essentially the same initial capacity or, in other words, were constructed with essentially the same design capacity.

[0039] Battery internal resistance generally increases with age, depending on the cell chemistry. This change in internal resistance influences, for example, battery performance. In conjunction with battery capacity determination, appropriate measurements provide a more complex picture for describing the effects of battery aging (performance, range).

[0040] The test parameters that can be used are, in particular, the same parameters, especially electrical operating parameters, as explained with regard to the aging parameters.

[0041] Preferably, the two battery sets have each been pre-aged to their battery capacities, in particular residual capacities, according to the pre-aging method according to the invention. This allows the battery sets to be provided with the batteries in a simple manner. In particular, several batteries of a battery set can, if possible, have the same predetermined aging state in the form of the same battery capacity if they have been pre-aged using the pre-aging method according to the invention for the test method according to the invention.

[0042] It is also possible to combine the test method according to the invention and the burn-in process according to the invention, with the burn-in process being performed before the test method. The burn-in process can be performed for at least one of the battery packs in the test method. Advantageously, the battery pack arrangements or circuits used for the burn-in process can also be used for the test method.

[0043] Preferably, the test parameters specified in the test plan are different for the batteries. This allows testing of identical batteries, especially at different SOHs, with different test parameters to obtain different aging information regarding the aging of the batteries as a result of the test.

[0044] For example, it can be found out how strongly battery aging is influenced by temperature if, for example, one battery is tested at 20 °C, another battery at 0 °C, and yet another battery at -20 °C according to the test plan. The test parameter by which the batteries differ is therefore the ambient temperature. This test can therefore provide different information regarding the aging behavior at different temperatures for a specific battery type. In addition, there is the advantage of providing battery sets with different battery capacities. If, for example, testing is to be carried out in an SOH range of 100% to 80% SOH, a first battery set with three first batteries is provided at 100% SOH and a second battery set with three second batteries at 90% SOH.These are tested according to the test plan, so that one battery from each battery set is tested at 20°C, at 0°C, and at -20°C. This allows the test time of the test procedure to be approximately halved compared to a test procedure in which a battery set with three batteries would have to be fully aged from 100% SOH to 80% SOH. Nevertheless, the same amount of aging information is obtained across the entire SOH range from 100% to 80%.

[0045] The present invention also relates to a computer program product comprising instructions which, when the program is executed by a computer, cause the computer to carry out the pre-aging method according to the invention and / or the test method according to the invention.

[0046] Thus, a computer program product according to the invention brings with it the same advantages as have been explained in detail with reference to the pre-aging method according to the invention and the test method according to the invention.

[0047] The computer program product can be a computer program itself or a product, such as a computer-readable data storage device, on which a

[0048] Computer program for carrying out the pre-aging process according to the invention and / or the test process according to the invention can be stored.

[0049] Furthermore, the aforementioned task is solved by a pre-aging system for pre-aging at least one battery to a specified aging state. The pre-aging system comprises the following modules:

[0050] - at least one specification module for specifying the ageing state of the battery to be achieved,

[0051] - at least one selection module for selecting at least one aging profile from a plurality of different aging profiles, each of the aging profiles specifying a charging and / or discharging process with predefined aging parameters for the battery, and for selecting a further aging profile from the plurality of different aging profiles, the further aging profile differing in at least one of the predefined aging parameters from the previously selected aging profile applied to the battery,

[0052] - at least one application module for applying the previously selected at least one aging profile to the battery and for applying the previously selected further aging profile to the battery, and - at least one determination module for determining whether the predetermined aging state of the battery has been reached.

[0053] Thus, a pre-aging system according to the invention brings with it the same advantages as have been explained in detail with reference to the pre-aging method according to the invention.

[0054] In particular, the pre-aging system can be configured to carry out the pre-aging method according to the invention.

[0055] Individual or all modules of the pre-aging system can, for example, each be implemented by a separate computer program code or jointly by a common computer program code and / or by separate or common functional units of a computer or electronic components. It is also possible for individual modules to be implemented in a common module. The pre-aging system can, in particular, comprise one or more computers or be formed by the one or more computers that the individual modules may have.

[0056] Finally, the task mentioned above is also solved by a test system for testing battery packs. The test system comprises the following modules:

[0057] - at least one provision module for providing a first battery set with at least one first battery having a first battery capacity and for providing at least one second battery set with at least one second battery having a second battery capacity different from the first battery capacity,

[0058] - at least one specification module for specifying the test plan for testing the battery sets, wherein the test plan specifies charging and / or discharging processes with predefined test parameters for the battery sets, and

[0059] - at least one test module for parallel testing of the two battery sets according to the specified test plan.

[0060] Parallel testing can, for example, be performed separately or jointly. This means that at least one test module can be used to test the two battery sets separately or in parallel. Thus, a test system according to the invention offers the same advantages as those explained in detail with reference to the test method according to the invention.

[0061] In particular, the test system can be configured to carry out the test method according to the invention.

[0062] The test system and the pre-aging system can also be combined into a common system, whereby individual modules, such as the specification module, can be provided only once and can be used for the test system and the pre-aging system.

[0063] Individual or all modules of the test system can, for example, each be implemented by a separate computer program code or jointly by a common computer program code and / or by separate or common functional units of a computer or electronic components. It is also possible for individual modules to be implemented in a common module. The test system can, in particular, comprise one or more computers or be formed by the one or more computers that the individual modules may have.

[0064] Further advantages, features, and details of the invention will become apparent from the following description, in which exemplary embodiments are described in detail with reference to the drawings. They show schematically:

[0065] Fig. 1 is a schematic representation of a battery circuit,

[0066] Fig. 2 is a schematic representation of a pre-aging process according to an embodiment of the invention,

[0067] Fig. 3 is a schematic representation of a pre-aging system according to an embodiment of the invention,

[0068] Fig. 4 is a schematic representation of the aging of batteries by an aging method according to the prior art, Fig. 5 is a schematic representation of the aging of batteries by the pre-aging method of Fig. 2 or the pre-aging system of Fig. 3,

[0069] Fig. 6 is a schematic representation of a test method according to an embodiment of the invention,

[0070] Fig. 7 is a schematic representation of a test system according to an embodiment of the invention,

[0071] Fig. 8 is a schematic representation of an alternative to the test system of Fig. 7;

[0072] Fig. 9 is a schematic representation of an alternative to the test system of Fig. 7, particularly in combination with Fig. 8;

[0073] Fig. 10 is a further schematic representation of the ageing of batteries by the pre-ageing method of Fig. 2 or the pre-ageing system of Fig. 3, and

[0074] Fig. 11 is a schematic representation of the aging of batteries during the test procedure of Fig. 6 or the test system of Fig. 7.

[0075] Identical or functionally equivalent elements are designated by the same reference numeral in Figures 1 to 11.

[0076] Figure 1 schematically shows a battery circuit 1 with several batteries 2 connected in parallel to a voltage source 3 for charging the batteries 2 and a load 4 for discharging the batteries 2. Switches 5 in the battery circuit 1 can be used to connect the voltage source 3 and the load 4, respectively. The batteries 2 can be identical in construction. The batteries 2 can be, for example, battery cells, battery modules, or battery packs.

[0077] As indicated in Fig. 1 by three continuation points each, more than the five batteries 2 shown by way of example can be connected in parallel. Alternatively, it is also possible for fewer than five batteries 2, for example only two or only one battery 2, to be provided in the battery circuit 1. Furthermore, it can also be provided that each of the batteries 2 is assigned its own voltage source 3, its own consumer 4 and / or its own switch 5, so that Fig. 1 shows only a simple variant of a possible battery circuit 1, which allows the pre-aging process 10 explained with regard to Fig. 2.

[0078] The pre-aging method 10 serves to pre-age one or more batteries 2 (referred to below) of the battery circuit 1 to a predetermined aging state. In a pre-aging step 11 of the pre-aging method 10, the desired aging state of the batteries 2 is specified.

[0079] In a first selection step 12, an aging profile is then selected from a multitude of different aging profiles. Each of the aging profiles specifies a specific number of charge / discharge cycles with predefined aging parameters for the batteries 2, which are carried out using the voltage source 3 and the load 4. The aging parameters can be, for example, environmental parameters such as temperature or mechanical pressure on the batteries 2 and electrical operating parameters such as charging and discharging current. In a first application step 13, the aging profile selected in the first selection step 12 is applied to the batteries 2.

[0080] The first selection step 12 and the first application step 13 are now essentially repeated by a second selection step 14 and a second application step 15, whereby further repetitions are also possible, as indicated in Fig. 2 by three continuation points, until the predetermined aging state of the batteries 2 is reached. In contrast to the first selection step 12, in the second selection step 14 and possibly further, i.e. third, fourth, etc., selection steps (not shown here), an aging profile different from the previously applied aging profile is selected. The aging profile differs in one or more of the predefined aging parameters, so that the batteries 2 are subjected to different loads in the different aging profiles.

[0081] Figure 3 shows a pre-aging system 20 as can be used to carry out the pre-aging method 10 of Fig. 2. The pre-aging system 20 has a specification module 21 for carrying out the specification step 11, a selection module 22 for carrying out the selection steps 12, 14, an application module 23 for carrying out the application steps 13, 15, and a determination module 24, which determines whether the pre-defined aging state of the batteries 2 has been reached and thus allows the termination of the pre-aging method 10.

[0082] Figure 4 shows the aging of five batteries 2 in a diagram of SOH (State of Health) indicating the remaining capacity of the batteries 2 compared to their design capacity (normalized to 100%) over the number n of charge / discharge cycles according to the prior art. In an aging process according to the prior art, a specific charge / discharge cycle is applied to each of the batteries 2, which remains the same throughout. On the one hand, this leads to individual batteries 2 taking a very long time to reach a certain aging state, for example, SOH = 80% (the top three batteries 2 in Fig. 4 need over n = 1,000 cycles). On the other hand, this leads to the visible uneven aging. Accordingly, it is not possible to age the batteries 2 evenly using the prior art process.

[0083] If the method shown in Fig. 4 is used as a test method in which aging information about the batteries 2 is obtained, this is unsatisfactory because after 1,000 cycles for all batteries 2, no statement can be made about their aging behavior depending on the specific charge / discharge cycles over the same SOH range of, for example, 100% to 75%.

[0084] The situation is different with the pre-aging process 10 according to the invention, the result of which is visible in the diagram in Figure 5. Here, the batteries 2 were pre-aged according to the pre-aging process 10 with the pre-aging system 20 and reached an SOH of approximately 80% more quickly (after approximately n = 1,000 cycles) and also aged much more evenly, so that their SOH is comparable.

[0085] When the pre-aging method 10, as used in Fig. 5, is used as a test method for obtaining aging information, all five batteries 2 could be tested over a SOH range from 100% to approximately 80% with different aging profiles, thus providing a greater wealth of information on aging. However, it is even more preferable to use the pre-aging method 10 before the actual test method 30, as shown in Fig. 6.

[0086] Figure 6 schematically shows a test method 30 for testing battery packs, such as the battery pack of Figure 1 comprising the five batteries 2 shown therein and another battery pack, not shown, which in turn comprises a plurality of batteries 2. Figure 7 shows a corresponding test system 40 by which the test method 30 can be carried out.

[0087] In a first provisioning step 31, a provisioning module 41 provides a first battery set comprising first batteries 2 having a first battery capacity, in particular residual capacity, for example connected in a battery circuit 1 such as that shown in Fig. 1. In a second provisioning step 32, the same provisioning module 41 of the test system 40 provides a second battery set comprising second batteries 2 having a second battery capacity that differs from the first battery capacity.

[0088] As can be seen in Fig. 7 and Fig. 11, the first battery set can, for example, have three batteries 2 with battery capacities of 100% SOH and the second battery set can, for example, also have three batteries 2 with battery capacities of 90% SOH, which have been pre-aged quickly and evenly with few cycles, in particular according to the pre-aging method 10 according to the invention.

[0089] In Fig. 7 it is indicated here that further provision steps (not shown) are possible in order to provide further battery sets with further batteries 2 in which the batteries 2 have other SOHs, for example 95% SOH and 85% SOH, whereby the test method 30 can be accelerated even further, as will become clear from the following.

[0090] A specification module 42 of the test system 40 then executes a specification step 33 to specify the test plan for testing the battery sets. The test plan specifies charge / discharge cycles with predefined test parameters for the battery sets, which vary for the batteries 2 being tested.

[0091] A test module 43 then performs a test step 34 in which the battery packs are tested in parallel according to the specified test plan. The result can be seen in Fig. 11, which shows that the batteries 2 in the SOH range from 100 to approximately 80% are fully tested in only 600 cycles, instead of over 1,000 cycles and only in a partially consistent SOH range from 100% to just under 95% of all batteries 2, as would be the case with an aging test according to Fig. 4.

[0092] Unlike what is shown in Fig. 7, the provision of battery sets 1 with different capacities (e.g., 95%, 90%, etc.) can also be carried out in parallel. Accordingly, the test method 30 can be performed on the different battery sets 1 with different capacities. Accordingly, different test systems 40 can also be used, on which the battery sets 1 with different capacities are tested in parallel or sequentially, as shown by way of example in Figs. 8 and 9, wherein the data from both test systems 40 of Figs. 8 and 9 can subsequently be combined.

[0093] Figure 10 shows a battery capacity corridor 50, as preferably maintained by a predefined parameter range for the aging parameters of the aging profiles. Alternatively or additionally, the battery capacity corridor 50 can be maintained by determining and providing feedback on intermediate aging states of the batteries 2. The feedback can be performed in selection step 14 and in further selection steps in order to select the further aging profile of the batteries 2 such that all batteries 2 are within the battery capacity corridor 50 and reach the predefined aging state as simultaneously as possible.

[0094] The above explanations of the embodiments describe the present invention exclusively by way of examples.

[0095] List of reference symbols

[0096] 1 battery circuit

[0097] 2 batteries

[0098] 3 Voltage source

[0099] 4 consumers

[0100] 5 switches

[0101] 10 pre-aging processes

[0102] 11 Default step

[0103] 12 first selection step

[0104] 13 first application step

[0105] 14 second selection step

[0106] 15 second application step

[0107] 20 Pre-aging system

[0108] 21 Specification module

[0109] 22 Selection module

[0110] 23 Application module

[0111] 24 Determination module

[0112] 30 test procedures

[0113] 31 first deployment step

[0114] 32 second deployment step

[0115] 33 further default step

[0116] 34 Test step

[0117] 40 test system

[0118] 41 Deployment module

[0119] 42 Specification module

[0120] 43 Test module

[0121] 50 battery capacity corridor

Claims

Patent claims 1. Pre-aging method (10) for pre-aging at least one battery (2) to a predetermined aging state, wherein the pre-aging method (10) is characterized by the following steps: - Specifying (11) the aging state to be achieved of the battery (2), - Selecting (12) at least one aging profile from a variety of different aging profiles, wherein each of the aging profiles specifies at least one charging and / or discharging process with predefined aging parameters for the battery (2), - Applying (13) the previously selected at least one aging profile to the battery (2), - Selecting (14) at least one further aging profile from the multitude of different aging profiles, wherein the further aging profile differs in at least one of the predefined aging parameters from the previously selected aging profile applied to the battery (2), - Applying (15) the previously selected at least one further aging profile to the battery (2) until the specified aging state of the battery (2) is reached.

2. Pre-aging method (10) according to claim 1, characterized in that, until the predetermined aging state of the battery (2) is reached, further aging profiles are selected from the plurality of different aging profiles and applied to the battery (2), wherein the further aging profiles differ in at least one of the predefined aging parameters from the previously selected aging profile applied to the battery (2).

3. Pre-aging method (10) according to claim 1 or 2, characterized in that at least one of the selected aging profiles is configured for aging the battery (2) at a first rate and at least one other the selected aging profiles for aging the battery (2) are set up with a second speed different from the first speed.

4. Pre-aging method (10) according to one of the preceding claims, characterized in that the specified aging parameters are at least two of a temperature, a mechanical pressure, a charging current, a discharging current, a state of charge and a pulse frequency.

5. Pre-aging method (10) according to one of the preceding claims, characterized in that the specified aging parameters in the aging profiles lie within a specified parameter range.

6. Pre-aging method (10) according to one of the preceding claims, characterized in that the predetermined aging state is in the range of 95% to 70% residual capacity measured against a design capacity of the battery (2).

7. Pre-aging method (10) according to one of the preceding claims, characterized in that several batteries (2) are pre-aged in parallel, wherein the predetermined aging state is the same for all batteries (2).

8. Pre-aging method (10) according to claim 7, characterized in that, in order to achieve the predetermined aging state of all batteries (2), the aging profiles for the batteries (2) are selected taking into account intermediate aging states of the other batteries (2).

9. Test procedure (30) for testing battery sets according to a specified test plan, wherein the test procedure (30) is characterized by the following steps: - Providing (31) a first set of batteries comprising at least one first battery (2) having a first battery capacity, - Providing (32) at least one second battery set with at least one second battery (2) having a second battery capacity different from the first battery capacity, - Specifying (33) the test plan for testing the battery sets, wherein the test plan specifies charging and / or discharging operations with predefined test parameters for the battery sets, and - parallel testing (34) of the two battery sets according to the specified test plan.

10. Test method (30) according to claim 9, characterized in that the two battery sets have each been pre-aged to their battery capacities according to the pre-aging method (10) according to one of claims 1 to 8.

11. Test method (30) according to claim 9 or 10, characterized in that each of the battery sets comprises several batteries (2).

12. Test method (30) according to one of claims 9 to 11, characterized in that the test parameters specified by the test plan for the batteries (2) are different.

13. Computer program product comprising instructions which, when the program is executed by a computer, cause it to execute the pre-aging process (10) according to any one of claims 1 to 8 and / or the test method (30) according to any one of claims 9 to 12.

14. Pre-aging system (20) for pre-aging at least one battery (2) to a predetermined aging state, wherein the pre-aging system (20) is characterized by the following modules (21 , 22, 23, 24): - at least one preset module (21 ) for specifying the aging state to be achieved of the battery (2), - at least one selection module (22) for selecting at least one aging profile from a plurality of different aging profiles, wherein each of the aging profiles specifies a charging and / or discharging process with predefined aging parameters for the battery (2), and for selecting a further aging profile from the plurality of different aging profiles, wherein the further aging profile differs in at least one of the predefined aging parameters from the previously selected aging profile applied to the battery (2), - at least one application module (23) for applying the previously selected at least one aging profile to the battery (2) and for applying the previously selected further aging profile to the battery (2), and - at least one determination module (24) for determining whether the specified aging state of the battery (2) has been reached.

15. Test system (40) for testing battery sets, wherein the test system (40) is characterized by the following modules: - at least one provisioning module (41) for providing a first battery set with at least one first battery (2) having a first battery capacity and for providing at least one second battery set with at least one second battery (2) having a second battery capacity different from the first battery capacity, - at least one specification module (42) for specifying the test plan for testing the battery sets, wherein the test plan specifies charging and / or discharging processes with predefined test parameters for the battery sets, and at least one test module (43) for testing the two battery sets in parallel according to the specified test plan.

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