Storage battery device supporting natural equalization

Abstract

The invention relates to the technical field of storage batteries, and discloses a storage battery device supporting natural equalization, comprising: an annular dislocation switch comprising N pairs of static contacts and M pairs of moving contacts which are annularly and correspondingly distributed, the N pairs of static contacts forming a first annular structure and maintained at a fixed position, and the M pairs of moving contacts forming a rotatable second annular structure Ngt; = M; the first battery pack comprises N first batteries which are sequentially connected in series, and positive electrodes and negative electrodes of the N first batteries are electrically connected to the N pairs of static contacts respectively; the second battery pack comprises M mutually independent second batteries, and the M second batteries are electrically connected to the M pairs of moving contacts respectively; the annular dislocation switch is provided with N designated positions, and when the second annular structure rotates to any designated position, each pair of moving contacts is electrically connected with one pair of static contacts, so that the corresponding first batteries and second batteries are naturally balanced through parallel connection. The invention provides an efficient and stable storage battery equalization scheme.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to battery balancing technology. Background Art

[0002] As lithium battery technology matures, its application in power drive and energy storage has gradually been widely recognized. The high energy density and long life of lithium batteries make them show great potential in multiple scenarios such as new energy vehicles, renewable energy storage and backup power. However, the voltage of a single battery cell is usually low. In order to meet the voltage requirements of different applications, it is common to connect multiple battery cells in series.

[0003] However, this series connection brings a significant problem. Since each battery cell has slight differences in capacity and performance during the production process, these differences will be amplified during the continuous charge and discharge process, resulting in uneven use between battery packs. Over time, some batteries may be overused or overcharged, while some batteries may fail to fully release their stored energy, thus affecting the performance and life of the entire battery pack.

[0004] In order to deal with this unevenness problem, researchers have proposed a series of balancing strategies, which can be roughly divided into two categories: active balancing and passive balancing. Regardless of which balancing strategy is used, the core idea is to add additional compensation circuits outside the battery pack to adjust the battery cells with inconsistent performance to ensure that the entire battery pack can work more evenly.

[0005] However, these traditional balancing strategies all have certain defects. In terms of efficiency, the external compensation circuit may consume extra energy, resulting in lower overall efficiency; in terms of cost, adding external circuits will increase manufacturing and maintenance costs; in terms of user experience, complex compensation mechanisms may make battery use and maintenance more complicated; and in terms of balancing effect, due to the different characteristics and usage of each battery cell, external compensation often fails to achieve the ideal balancing effect.

[0006] Therefore, even though lithium battery technology has developed for decades, the balancing problem of long strings of batteries remains a major challenge in the field, and an innovative and comprehensive solution is urgently needed. Summary of the invention

[0007] The purpose of the present application is to provide a battery device that supports natural equalization to solve the problems raised in the above background technology.

[0008] The present application discloses a battery device supporting natural equalization, comprising:

[0009] An annular staggered switch, comprising N pairs of stationary contacts and M pairs of moving contacts distributed in a ring shape in a corresponding manner, wherein the N pairs of stationary contacts constitute a first annular structure and are kept in a fixed position, and the M pairs of moving contacts constitute a rotatable second annular structure, wherein N is a positive integer greater than or equal to 2, and M is a positive integer greater than 1 and less than or equal to N;

[0010] A first battery group includes N first batteries connected in series in sequence, wherein the positive and negative electrodes of the N first batteries are electrically connected to the N pairs of static contacts respectively;

[0011] A second battery pack includes M second batteries that are independent of each other, wherein the M second batteries are electrically connected to the M pairs of moving contacts respectively;

[0012] The annular staggered switch has N designated positions. When the second annular structure rotates to any designated position, each pair of moving contacts is electrically connected to a pair of static contacts, so that the corresponding first battery and second battery are naturally balanced by parallel connection.

[0013] In a preferred embodiment, M=N.

[0014] In a preferred example, it also includes a driving device for driving the second annular structure to rotate from one designated position of the annular offset switch to another designated position, so as to achieve natural balance of each second battery in the second battery group by parallel connection with different first batteries.

[0015] In a preferred example, the driving device includes a motor and a controller;

[0016] The controller is used to control the motor to periodically drive the second annular structure to rotate from a specified position of the annular offset switch to the next specified position, and stay at each specified position for a predetermined period of time, so that each second battery in the second battery group is connected in parallel with each first battery in the first battery group to achieve natural balance.

[0017] In a preferred example, the single cell capacity of the first battery group is greater than the single cell capacity of the second battery group.

[0018] In a preferred example, the ratio of the single cell capacity of the second battery pack to the single cell capacity of the first battery pack ranges from 0.02 to 0.25.

[0019] In a preferred embodiment, the N pairs of static contacts are evenly arranged in a ring shape on the first ring structure;

[0020] The M pairs of moving contacts are evenly arranged in a ring shape on the second ring structure.

[0021] In a preferred example, the first annular structure and the second annular structure are coaxial, and the second annular structure can rotate around the axis.

[0022] In a preferred embodiment, it also includes lead-out electrodes for leading out the positive and negative electrodes of the first battery pack and electrically connecting them to an external power-consuming device or a charging device.

[0023] In a preferred example, the capacity of the storage battery device is the sum of the capacities of all batteries in the first battery group and the second battery group.

[0024] The embodiments of the present application have the following beneficial effects:

[0025] Battery balancing: Through the contact between the moving contact and the stationary contact, the first battery group and the second battery group can be connected in parallel, which helps to achieve balancing between the batteries. Balancing helps to increase the service life of the battery system and prevent some batteries from failing prematurely or causing thermal runaway.

[0026] Flexibility and adjustability: The rotating moving contact design provides the flexibility to connect or disconnect different battery packs, which means that balancing operations can be performed as needed. In addition, the motor and controller make the rotation of the rotating disk more accurate, flexible and controllable.

[0027] Material advantages: Using highly conductive materials (such as silver alloys) as contact materials can reduce contact impedance, thereby improving overall efficiency and reducing energy loss.

[0028] Selection of battery capacity: The design of the single battery capacity of the first battery group is greater than that of the second battery group, which means that when balancing between battery groups, the first battery group can provide more power to the second battery group. When the battery capacity of the first battery group is more than twice that of the second battery group, it provides the system with better series main circuit efficiency and takes into account the balancing requirements.

[0029] Output design optimization: The output terminal is configured by connecting the specific positive and negative electrodes of the first battery group so that the output voltage can reach the maximum to meet the needs of the external device or system.

[0030] In summary, this application provides an effective, reliable and safe battery equalization solution, which aims to extend the service life of the battery, improve its efficiency and ensure safety during use. This design is particularly suitable for battery systems that require long-term stable operation and high requirements, such as large energy storage systems, electric vehicles or other high-performance applications.

[0031] A large number of technical features are recorded in the specification of this application, which are distributed in various technical solutions. If all possible combinations of technical features of this application (i.e., technical solutions) are to be listed, the specification will be too long. In order to avoid this problem, the various technical features disclosed in the above-mentioned invention content of this application, the various technical features disclosed in the various embodiments and examples below, and the various technical features disclosed in the accompanying drawings can be freely combined with each other to form various new technical solutions (these technical solutions are all deemed to have been recorded in this specification), unless the combination of such technical features is technically infeasible. For example, in one example, feature A+B+C is disclosed, and in another example, feature A+B+D+E is disclosed, and features C and D are equivalent technical means that play the same role. Technically, only one can be used, and it is impossible to use them at the same time. Feature E can be combined with feature C technically. Then, the solution of A+B+C+D should not be deemed to have been recorded because it is technically infeasible, and the solution of A+B+C+E should be deemed to have been recorded. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 Schematic diagram of the structure of a battery device supporting natural equalization according to the first embodiment of the present application DETAILED DESCRIPTION

[0033] In the following description, many technical details are provided to help readers better understand the present application. However, those skilled in the art can understand that the technical solution claimed in the present application can be implemented even without these technical details and various changes and modifications based on the following embodiments.

[0034] After in-depth research, the inventors of the present application found that battery inconsistency is a common problem. But in fact, when inconsistent batteries work in parallel, they can be used normally without inconsistency problems. The battery voltage in a parallel circuit is the same, and the current is the same in a series circuit. In a series circuit, since the current is the same, regardless of the difference in capacity between the batteries, each battery works at the same rate, causing the battery with a smaller capacity to be exhausted faster. It can be understood that the physical and chemical principles of the battery determine that its internal voltage varies with the state of charge of the battery. When the batteries are connected in parallel, the voltages of each battery will tend to be consistent, that is, each battery will naturally synchronize and maintain the same state of charge, so that no additional balancing measures are required. This characteristic is called the "natural balance" of the battery.

[0035] Although it has been proposed in the past to use a switch array to convert batteries from series mode to parallel mode to achieve battery balancing, this method has not been widely used in actual commercial applications due to the contact loss and cost of the switch. This application is an innovative solution to this challenge. It not only retains the series connection mode of the battery, but also achieves "natural balancing" without additional losses regardless of the charging, discharging or storage state, fundamentally solving the problem of inconsistency of long strings of batteries.

[0036] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below in conjunction with the accompanying drawings.

[0037] The first embodiment of the present application relates to a battery device supporting natural equalization, the structure of which is as follows: Figure 1 As shown, the device comprises:

[0038] A ring-shaped staggered switch includes N pairs of static contacts distributed in a ring-shaped manner ( Figure 1 The black thick short line segment) and M pair moving contact ( Figure 1 Corresponding to the arrow of the thick black line segment), N pairs of static contacts form a first ring structure ( Figure 1 The outer ring) is kept in a fixed position, and the M pair of moving contacts forms a rotatable second annular structure ( Figure 1 The first ring structure is a ring structure with a plurality of pairs of moving contacts arranged in a circle. The second ring structure is a ring structure with a plurality of pairs of moving contacts arranged in a circle. The first ring structure and the second ring structure are coaxial, and the second ring structure can rotate around the axis.

[0039] The first battery group includes N first batteries connected in series in sequence, wherein positive and negative electrodes of the N first batteries are electrically connected to N pairs of static contacts respectively.

[0040] The second battery pack includes M second batteries that are independent of each other, wherein the M second batteries are electrically connected to M pairs of moving contacts respectively.

[0041] The annular staggered switch has N designated positions. When the second annular structure rotates to any designated position, each pair of moving contacts is electrically connected to a pair of static contacts, so that the corresponding first battery and second battery are naturally balanced by parallel connection.

[0042] Preferably, in one embodiment, M=N, that is, the number of batteries in the first battery group and the second battery group is the same, so that each battery in the first battery group can be connected in parallel with a battery in the second battery group to achieve balancing. In other embodiments, the number of batteries in the first battery group can also be greater than the number of batteries in the second battery group, so that although some batteries in the first battery group do not have corresponding second batteries during each parallel balancing, as the moving contact group rotates, each battery in the first battery group can also be connected in parallel with each battery in the second battery group in turn to achieve balancing.

[0043] Optionally, in one embodiment, a driving device is further included for driving the second annular structure to rotate from one designated position of the annular offset switch to another designated position, so that each second battery in the second battery pack is naturally balanced by being connected in parallel with different first batteries.

[0044] The drive device can be implemented in various ways.

[0045] Optionally, in one embodiment, the driving device includes a motor and a controller; the controller is used to control the motor to periodically drive the second annular structure to rotate from a specified position of the annular offset switch to the next specified position, and stay at each specified position for a predetermined period of time, thereby achieving natural balance by connecting each second battery in the second battery group in parallel with each first battery in the first battery group.

[0046] Optionally, in one embodiment, the driving device may also be a manual driving device, for example, driving the second annular structure to rotate through a rocker arm and a gear transmission mechanism.

[0047] Optionally, in one embodiment, the single cell capacity of the first battery group is greater than the single cell capacity of the second battery group. For example, the value range of the single cell capacity of the second battery group / the single cell capacity of the first battery group is 0.02 to 0.25. Of course, the relative size relationship between the single cell capacity of the first battery group and the single cell capacity of the second battery group can also be determined as needed.

[0048] In the above structure, the capacity of the storage battery device is the sum of the capacities of all batteries in the first battery group and the second battery group.

[0049] The structure of the above embodiment is described in further detail below.

[0050] As described above, the number of batteries in the first battery group and the second battery group is equal. However, the present application is not limited thereto, and in other embodiments, the number of batteries in the first battery group and the second battery group can be adjusted according to actual needs.

[0051] It should be pointed out that in the application of battery technology, the number of battery packs plays a vital role in the overall performance and stability. In some designs, in order to ensure balanced and stable energy output, we may choose to make the number of batteries in the first battery pack equal to that in the second battery pack. Such a configuration can ensure the energy transfer and complementarity between the two battery packs, thereby improving the overall output efficiency and stability.

[0052] However, actual application scenarios and requirements may be different, and the design concept of the present application is flexible enough to adapt to various situations. This means that even in the above preferred embodiment, the number of batteries in the two battery packs is equal, but in other embodiments, the number of batteries in the first battery pack and the second battery pack can be appropriately adjusted according to specific working conditions, battery performance or other relevant factors. For example, in high-load applications, the first battery pack may require more batteries to provide greater power, while the second battery pack focuses more on backup and supplementary functions, so the number of batteries in the second battery pack is relatively less than the number of batteries in the first battery pack.

[0053] In general, although a two-battery pack configuration of equal quantity may be ideal in some cases, the design concept of this application always focuses on practical application and flexibility to ensure that the best battery solution can be provided to users in various scenarios.

[0054] As mentioned above, in order to ensure the load capacity of the series main circuit, the capacity of the single cell of the first battery group is more than twice the capacity of the single cell of the second battery group, which can effectively reduce the switching energy consumption. In order to ensure the efficient and stable operation of the battery, when considering two battery systems, the configuration coefficient of its capacity is particularly important. Specifically, assuming that the capacity of the first group of batteries is A and the capacity of the second group of batteries is B, then its configuration coefficient is defined as: B capacity / A capacity. As mentioned above, this coefficient should be <0.5, and further, the optimal value range is 0.02 to 0.25. When the configuration coefficient falls within this range, it can ensure that the energy transfer between the two sets of batteries is more balanced, thereby improving the overall efficiency and service life of the battery pack.

[0055] Optionally, the main materials of the static contact and the moving contact are both made of copper material, and silver alloy contacts are used to obtain better electrical conductivity, thermal conductivity and longer life.

[0056] Optionally, the moving contact is designed to be able to rotate 360 ​​degrees. Optionally, the battery device supporting natural equalization of this embodiment is also equipped with a rotating disk, on which a second battery pack is fixed and connected to the moving contact. Optionally, in order to drive the rotation of the rotating disk, a motor is also equipped inside the device. A controller connected to the motor can control the motor, thereby adjusting the rotation speed and direction of the rotating disk.

[0057] Specifically, in this embodiment, the moving contact is not just a simple contact point, it has the function of being able to rotate in all directions, that is, 360 degrees. This all-round rotation design increases the flexibility of the contact and the static contact docking, ensuring that accurate docking can be achieved in various possible relative positions. This rotation design helps to improve the working efficiency and stability of the device, ensuring that excellent contact performance can be maintained under various working conditions. Further, in order to achieve this rotation design, a special rotating disk is introduced in this embodiment. This rotating disk is not only a supporting platform for the moving contact, but also used to fix the second battery pack. Through this design, the rotating disk, the moving contact and the second battery pack form a unified rotating module, which can ensure that the relative positions of the components remain stable during the rotation process. Further, in order to drive the rotating disk to rotate accurately, optionally, the device of this embodiment may further include a motor, which is the power source of the rotating module and is responsible for driving the rotating disk, the moving contact and the second battery pack to rotate. At the same time, in order to achieve precise control of the rotation, a controller is also introduced. This controller is directly connected to the motor, and can adjust the working state of the motor according to the needs of the system, thereby controlling the rotation speed and direction of the rotating disk. In this way, the device can dynamically adjust the rotation of the rotating disk according to actual working conditions and needs, ensuring that the battery packs can always achieve the best parallel working state.

[0058] Optionally, the positive output terminal of the storage battery device supporting natural balancing is connected to the negative electrode of the first battery in the first battery group, and the negative output terminal is connected to the positive electrode of the Nth battery in the first battery group.

[0059] Specifically, all the batteries of the first battery group are fixedly connected in series, and the positive and negative ends of the series battery group are respectively connected to the positive and negative output ends of the battery device to form a common main circuit. No other switches or resistors are introduced into the main circuit, ensuring efficient transmission and stable output of electric energy.

[0060] The working principle of the above embodiment is explained below:

[0061] Battery pack composition and contact function: The device of this embodiment includes two battery packs. The first battery pack is formed by a plurality of first batteries connected in series, and each first battery is equipped with a static contact of an annular structure. The second battery pack is composed of a plurality of independent second batteries, and each second battery is equipped with a movable contact of an annular structure, which is coaxial with the static contact. When it is necessary to realize the parallel connection of the first battery and the second battery, it is only necessary to rotate the movable contact to make it contact with the static contact.

[0062] Function of the staggered switch: In this embodiment, the staggered switch cooperates with the moving contact to ensure that when the moving contact is rotated, the positive or negative pole of the first battery and the second battery can be closed and connected. In this way, the moving contact not only relies on mechanical rotation to achieve contact, but also ensures the correct electrical connection, thereby connecting the two batteries in parallel.

[0063] Battery pack balancing: When there is a voltage difference between the cells of two battery packs, it means that the charge states of these cells are different. In this case, when the moving contact rotates to connect the first battery in parallel with the second battery, the current will flow from the battery with higher voltage to the battery with lower voltage, thus achieving natural balancing.

[0064] Specifically, for example, if a first battery in the first battery pack has a higher voltage, and a second battery in the second battery pack has a lower voltage, then when the moving contact rotates to connect the two batteries in parallel, the first battery with a higher voltage will supply power to the second battery with a lower voltage, thereby achieving voltage balancing.

[0065] This type of balancing is achieved by the natural flow of current between cells without the need for additional equalizers or converters. Hence, it is called “natural balancing”.

[0066] Advantages of the system: The structure of the moving contact and the static contact can quickly realize the parallel connection of the battery, so as to quickly respond to the voltage imbalance and realize the rapid equalization of the battery pack. In addition, this method does not require additional energy conversion or consumption, so it is more efficient.

[0067] The dynamic working process is further described below:

[0068] When the device is working normally, the N first batteries in the first battery group are connected in series in sequence and serve as the main power output of the device. The M second batteries in the second battery group are independent of each other and form a ring coaxial structure through the dynamic contact head and the static contact head. Unlike other balancing circuits, the balancing action of this method works all the time. Whether it is charging, discharging, or storage, the dislocation balancing action will be performed at the preset interval to keep all batteries in a balanced state all the time. When the interval time arrives, the control motor drives the dynamic contact head to rotate, and the battery in the second battery group is dislocated and connected in parallel with the next position battery in the first battery group through the control of the dislocation switch. The battery group connected in parallel will be naturally balanced. If there is a slight voltage difference between the first battery and the second battery connected in parallel, the battery with higher voltage will provide current to the battery with lower voltage to redistribute and balance the power. With the time interval, the staggered parallel balancing is continuously performed. By utilizing the transfer effect of the staggered parallel connection, all the batteries in the second battery group can be effectively balanced with the batteries in the first battery group, thereby achieving the balance of all the batteries, that is, the internal voltages of all the batteries are equal, that is, regardless of the capacity differences of the batteries, all the batteries are in the same state of charge (SOC). Further, it can be understood that the charging and discharging of the battery is lossy. So if one battery charges another battery, it is also lossy. However, since this method is full-time balanced, when the battery group is charged or discharged, in fact, as long as the balancing current is less than the working current of the battery charging and discharging, then in fact, there is no real situation that one battery discharges and charges another battery. It is just that the proportion of the working current they bear has changed. That is to say, when charging, the battery with a low voltage will obtain more power with a larger current, while the battery with a high voltage will only have a smaller charging current and charge slower, and then the two parallel batteries will reach balance. When discharging, it is similar. It can be seen from this that as long as the configuration parameters are reasonable, this balancing method can be achieved without consuming any energy. More importantly, since there is no charge from one battery to another, there is no loss of battery life. This is a completely free balancing method.

[0069] Overall, this patent achieves automatic dynamic balancing of the battery pack through innovative design.

[0070] Technical effects:

[0071] Natural balancing is achieved: Through the offset switch between the first battery group and the second battery group and the rotating structure of the moving and static contacts, different batteries are allowed to be connected in parallel, so that the batteries naturally reach a balanced state without the need for an external compensation circuit.

[0072] Specifically, the first battery group and the second battery group are connected by an offset switch. This offset switch can selectively connect different batteries in the two battery groups in parallel by controlling the contact of the moving and static contacts. If the voltage of some batteries in the first battery group is higher than that of the batteries in the second battery group, when the offset switch connects these first batteries with higher voltage in parallel with the second batteries with lower voltage, according to the principle of parallel circuit, when the two batteries are connected in parallel, the current will flow from the high voltage to the low voltage, the voltage will tend to be the same, and the state of charge will be balanced. In other words, the first battery with high voltage will provide current to the second battery with low voltage, and pass the excess power until the voltage and power of both are the same. Subsequently, the offset switch continues to change the parallel combination between the first battery group and the second battery group, and continues to connect other unbalanced batteries in parallel to achieve the purpose of full balance. The whole process is completely realized by the spontaneous current flow between the batteries, and no external circuit is required. This is what this patent calls "natural balance". Compared with the traditional technology of using external circuits to force balance, this natural balance method does not require additional energy and loss, and is simple, reliable and efficient. This is the core innovation and breakthrough of this patent.

[0073] Completely eliminate the hazards of inconsistent long strings of batteries: In short, inconsistent long strings of batteries will bring about the "short board effect" loss, and poor batteries will enter a vicious cycle, accelerate aging, and even cause thermal runaway, leading to spontaneous combustion.

[0074] At present, the voltage of long string battery packs, whether for power batteries or energy storage batteries, reaches 300V or even 500V, and dozens to hundreds of batteries are often connected in series. Assuming that there is a poor battery in a long string of 100 batteries, with a capacity of only 90% of the other batteries, then due to the short board effect, the total capacity of the entire string of batteries is equivalent to a 10% reduction, resulting in significant waste.

[0075] Then, because poor batteries will be discharged earlier and fully charged earlier than other batteries, and the life loss is most significant when the battery is close to being fully charged and discharged, as the use progresses, poor batteries will enter a vicious cycle and accelerate aging.

[0076] It should be noted that as the poor battery ages faster, the internal resistance will continue to increase. When other batteries are still healthy, due to the series connection, the full load current will cause the poor battery to heat up quickly, which is the root cause of the spontaneous combustion of aged batteries.

[0077] The full-time dynamic natural balance achieved by this method ensures that all batteries in the entire battery pack are in a synchronous state of equal voltage and balanced charge state at any time, regardless of charging, discharging, or storage. All batteries are fully charged and exhausted at the same time, completely eliminating the three major hazards of inconsistent long strings of batteries mentioned above, protecting investment and ensuring safety.

[0078] Natural balancing: Different from other methods, this method uses the physical and chemical properties of "natural balancing" inherent in parallel connection of storage batteries. This balancing is based on the internal voltage difference of the battery. Other methods all measure the battery terminal voltage externally, try to infer the internal voltage of the battery through the external voltage of the battery, and use this as a basis for external balancing compensation. However, due to the complexity of the internal structure and chemical reaction process of the battery, the external voltage in different working states is far from the internal voltage of the battery. The method of using unreliable external voltage for balancing compensation sometimes makes things worse and is counterproductive. This is also the fundamental reason why the market is helpless about balancing and has to spend a lot of effort on battery sorting. The problem is that the consistency of the factory may be achieved through sorting, but the inconsistency of the batteries formed during the aging process has become an unsolvable problem. This method adopts the method of full-time dynamic dislocation parallel balancing, which completely gets rid of the dependence on external voltage. Based on the most basic physical and chemical properties of the battery, it uses the parallel natural balancing ability of the battery itself, which determines that this method is absolutely accurate and reliable. Therefore, it completely solves the balancing problem of long strings of batteries, which is a subversive innovation.

[0079] Full-time balancing: As mentioned above, this method is not based on measuring external voltages, and balancing is performed only when the voltages are different. Instead, it is a continuous staggered balancing according to a plan. At any time, the first battery and the second battery are working in parallel, and are continuously staggered at planned intervals. In other words, regardless of whether the internal voltages of the batteries are the same, they are constantly staggered in parallel. When the voltages are equal, they work in parallel, and when there are differences in voltage, they are naturally balanced while working. Regardless of charging, discharging or storage, continuous staggered balancing is performed according to a plan, so in fact, each battery is kept in a completely synchronized state in real time, and the power differences caused by individual inconsistent batteries in a short period of time will be balanced in time. The capacity of all batteries can be fully used, and the life of all batteries is reduced synchronously.

[0080] Synchronous aging, eliminating vicious cycles: As mentioned above, this method can always keep the charge and discharge depth and life consumption of each battery in a synchronized state. Poor batteries will not be fully charged or discharged prematurely. The charge and discharge cycles of all batteries are exactly the same, and the aging degree is in step. Therefore, the problem of individual batteries entering a vicious cycle and accelerated aging is completely solved. The possibility of thermal runaway caused by this is eradicated.

[0081] Low switching energy consumption: The use of a suitable configuration ratio of the first battery and the second battery capacity can greatly reduce the current of the second battery through the staggered switch, while most of the working current is provided by the first battery group fixed in series. In this way, the energy lost on the switch contacts can be greatly reduced, and the grouping efficiency can be improved. The cleverness of this method lies in that, although the idea of ​​parallel connection of batteries is used to achieve natural balance, the introduction of the switch network into the main circuit is avoided. The main circuit of this method is consistent with the ordinary long string battery grouping method, that is, the first battery group fixed in series. The main configuration purpose of the second battery group with a small capacity is to provide balanced capacity for staggered parallel connection.

[0082] Reduce switch manufacturing cost: One clever thing about this method is that, although the total voltage of the battery pack can be as high as hundreds of volts, since the second battery is independent and not connected in series with other batteries, there is no large voltage difference between the second battery and the corresponding first battery in parallel. The disconnecting voltage of the staggered switch contact is actually just the external voltage difference between the two batteries, that is, the voltage at the millivolt level. Such a low voltage cannot generate electric sparks at all. Therefore, this staggered switch does not need to design arc extinguishing measures, which greatly reduces the manufacturing cost.

[0083] Improved efficiency: By avoiding the use of external compensation circuits, the overall system efficiency is improved and energy losses are reduced.

[0084] Specifically, in traditional battery pack balancing solutions, it is often necessary to set up an external compensation circuit to achieve balancing between batteries. For example, a resistor is connected in parallel to consume the power in the battery with a higher voltage, or the voltage of the high-voltage battery is converted and output to the low-voltage battery through a conversion circuit. However, the use of such an external compensation circuit also brings about a loss of efficiency. The compensation circuit itself needs to consume a certain amount of power to drive its operation, and at the same time, some electric energy will be lost and converted into heat energy during the process of power conversion and transmission. The technical solution in this application realizes natural balancing inside the battery pack through innovative design, and no external compensation circuit is required. Inside the battery pack, the high-voltage battery can directly provide current to the low-voltage battery to achieve power redistribution. In this process, there is no need for power conversion or consumption through resistors, so the efficiency loss caused by the external compensation circuit itself can be avoided. Direct current transmission is achieved inside the battery pack through parallel connection, which saves the loss of power conversion, thereby improving the efficiency of the overall system. In short, the technical solution proposed in this application realizes natural balancing by utilizing the characteristics of the battery itself, avoids the use of an external compensation circuit, and thus improves the efficiency of the overall system, effectively reduces energy loss and waste, and achieves more efficient battery pack management. This is an important improvement in efficiency of this application.

[0085] Reduced cost: No additional external compensation circuits and complex control strategies are required, which reduces costs in manufacturing and maintenance.

[0086] Specifically, the traditional battery pack equalization solution requires the setting of an external compensation circuit, which not only increases the complexity of the circuit, but also increases the manufacturing cost. The external compensation circuit requires the additional production of a PCB board and the installation of electronic components such as resistors, capacitors, and integrated circuits. This undoubtedly increases the cost of materials and processes. At the same time, the external compensation circuit also requires the design of a complex control strategy to coordinate its work, which also puts higher requirements on the system software development and increases the R&D investment. However, the present application does not need to set up an external compensation circuit at all, nor does it need a measurement circuit for the battery external voltage through internal natural balancing. Its circuit structure and control strategy are greatly simplified. This not only reduces the use of materials, simplifies the manufacturing process, but also reduces the difficulty of R&D. Therefore, from a cost perspective, the present application saves the material cost and manufacturing cost of the external compensation circuit, and also reduces the investment in system R&D, which directly leads to a reduction in overall cost. In addition, due to the reduction of external compensation circuits, the reliability of the system is also improved, so the maintenance cost is reduced. Technicians do not need to frequently check or replace external circuits, which also reduces the maintenance workload. This also reduces the use cost of the entire system from another perspective. In summary, the present application simplifies the circuit structure and control strategy without adding an external compensation circuit, thereby directly reducing the manufacturing cost and maintenance cost, thereby reducing the cost of the entire system, which is one of its significant economic benefits.

[0087] Improved battery life: Since the battery packs can be better balanced, each battery cell can be charged and discharged more evenly, thus extending the service life of the entire battery pack.

[0088] Specifically, in the field of battery technology, the service life of a battery is directly related to the various stresses it endures during the charging and discharging process, and one of the important factors is the balance state between battery cells. Traditionally, due to slight differences between battery cells, such as slight variations in the manufacturing process or performance differences gradually generated during use, the battery pack may be unevenly charged and discharged during operation. This unevenness may cause a battery cell or multiple battery cells to be subjected to excessive charge pressure, thereby accelerating its aging. The present invention promotes the voltage and capacity balance between the battery cells inside the battery pack by implementing the staggered parallel connection technology. Such a design ensures that the charge pressure experienced by each battery cell during the charging and discharging process is more balanced, thereby reducing the potential risk of damage caused by uneven charging and discharging. Since the charging and discharging process is more stable, the chemical balance inside the battery cell can be effectively maintained, and unstable chemical reactions can be reduced, thereby extending the service life of the battery. Therefore, the present invention not only enhances the service life of a single battery cell by ensuring uniform charging and discharging of each battery cell in the battery pack, but also improves the stability and reliability of the entire battery pack, bringing users a more continuous and stable energy output.

[0089] Enhanced user experience: Simplifies the use and maintenance of the battery pack, making it more user-friendly and reducing potential risks caused by unbalanced.

[0090] Specifically, in many electronic devices and energy systems, battery packs are important energy supply components, and their stability, reliability, and convenience of use and maintenance directly affect the actual user experience. Traditional battery management systems may involve complex operations or periodic maintenance to ensure the stable operation of the battery pack. This not only increases the user's operating costs, but also may bring potential risks due to improper operation. The present invention significantly simplifies the use and maintenance process of the battery pack by optimizing the equalization technology of the battery pack. First, the automatic battery equalization function reduces the user's need to regularly check and manually adjust the battery equalization, so that the battery pack can maintain itself in a relatively stable state. Secondly, when each unit of the battery pack is maintained in a relatively balanced state, the operating efficiency of the equipment is improved, thereby providing a more stable and lasting energy output, giving the user a more enjoyable use experience. Furthermore, since the balance of the battery pack is improved, the risks caused by excessive discharge or charging of the single cell, such as excessive battery temperature, electrolyte leakage or battery expansion, or even spontaneous combustion, are reduced, thereby increasing the safety of the battery pack. This not only provides a safer use environment for users, but also avoids potential property losses caused by battery problems. Therefore, the present invention not only ensures the stability and safety of the battery pack through the automatic battery balancing technology, but also greatly improves the user's convenience, thereby comprehensively enhancing the user's overall experience.

[0091] Simplified structure: The annular coaxial design of the moving and static contacts and the setting of the offset switch simplify the structure of the battery pack, making it more compact and stable.

[0092] Specifically, the structure and design of the battery pack have a crucial impact on its performance, reliability and service life. Traditional battery packs often use complex connection and layout methods, which not only increases the volume and weight of the battery pack, but also may lead to maintenance difficulties, unstable connections and other problems. In the present invention, the annular coaxial design of the moving and static contacts is used to simplify and optimize the internal connection of the battery pack. This design has the following significant advantages:

[0093] (1) Reduce connection points: The annular coaxial design greatly reduces the number of connection points inside the battery pack, thereby reducing potential failure points and improving overall reliability.

[0094] (2) Improve space utilization: The annular coaxial design can more effectively utilize the space inside the battery pack, making the battery pack more compact and adaptable to more application scenarios and installation requirements.

[0095] (3) Enhanced mechanical stability: The simplified structure means fewer moving parts and connectors, so the battery pack can remain more stable under mechanical vibration or external impact, reducing the risk of failure due to physical damage.

[0096] In addition, the setting of the offset switch further optimizes the connection logic of the battery pack, making the current distribution between the battery packs more uniform and extending the battery life. This offset switch design also simplifies the circuit design of the battery pack, reduces the number of external lines and connectors, and further reduces the complexity of the system.

[0097] Therefore, through the annular coaxial design of the moving and static contacts and the setting of the offset switch, the present invention simplifies the battery pack structure, making it more compact, stable and reliable, which not only reduces the manufacturing and maintenance costs, but also improves the performance and service life of the battery pack.

[0098] In summary, the battery device provided in the present application provides an efficient, low-cost, simple and practical solution to solve the inconsistency problem of long battery strings.

[0099] In order to better understand the technical solution of the present application, a specific example is provided below for illustration. The details listed in the example are mainly for ease of understanding and are not intended to limit the scope of protection of the present application.

[0100] Based on the aforementioned "natural balance" idea, this example uses a novel dynamic staggered parallel method, that is, two strings of batteries are connected in parallel, and their alignment is continuously staggered through a special multi-to-multi staggered switch. In the states of charging, discharging, and storage, the two strings of batteries are continuously staggered in parallel, and the "natural balance" effect of the batteries in parallel is used to keep the battery pack in a balanced state after being grouped.

[0101] As mentioned above, the method uses two sets of batteries with equal numbers. Figure 1 Medium EA 1 To EA k Represents a set of A batteries, with a total of k cells; EB 1 To EB k Represents a set of B batteries, with a total of k cells. Each cell of the set A battery has two electrodes connected to two static contacts. The number of the static contacts follows the number of the battery. 1 Positive pole connected to static contact SC 1P , negative pole connected to static contact SC 1N ; ..., any battery EA i Positive terminal connected to SC iP , negative pole connected to SC iN ; ..., until the last battery, EA k Positive terminal connected to SC kP , negative pole connected to SC kN These static contacts are evenly arranged in a ring. These K sets of A batteries are connected in series, EA 1 Positive electrode connected to EA 2 Negative electrode, EA 2 Positive electrode connected to EA 3 Negative electrode, ..., and so on, EA i Positive electrode connected to EA i+1 Negative electrode, ..., until finally, EA k-1 Positive electrode connected to EA k Negative electrode. k The positive electrode is connected to the total positive terminal of the entire battery pack, EA 1 The negative electrode is connected to the total negative terminal of the group.

[0102] Similarly, the two poles of each B set of batteries are connected to two moving contacts, EB 1 Positive contact MC 1P , negative pole connected to MC 1N ; ..., any battery EB i Positive electrode connected to MC iP , negative pole connected to MC iN ; ..., finally, EB k Positive electrode connected to MC kP , negative pole connected to MC kN. Unlike the batteries in set A, the batteries in set B are not connected to each other. These moving contacts are fixed on the annular moving contact frame and are evenly arranged to form the moving contact group as a whole. The annular moving contact group is coaxial with the static contact. The moving contact group can rotate around this axis. Each moving contact has a corresponding static contact in the same position, which can be closed and connected with it. Obviously, when the moving contact group rotates, the corresponding relationship between each moving contact and the static contact in contact with it will change.

[0103] In short, a series of A batteries and an equal number of B independent batteries are connected together by a staggered switch, and then connected in parallel in pairs and then in series, similar to the "k series and 2 parallel" group. The difference is that as the moving contact group of the staggered switch rotates, the parallel connection objects between the A and B batteries are constantly changing. For example, in the initial position of the above figure, EA 1 With EB 1 Parallel, ..., EA i With EB i Parallel, ..., EA k With EB k Then, the moving contact group rotates an angle so that the moving contact MC 1N Align SC 2N , and close to connect, at this time, EA 2 With EB 1 Parallel, ..., EA i With EB i-1 Parallel, EA i+1 With EB i In parallel, ..., finally EA k With EB k-1 In parallel, EA 1 EB k In other words, the EB battery is "misplaced" one battery counterclockwise.

[0104] The following explains how this staggered parallel connection can achieve battery pack balancing:

[0105] Assuming Battery EA i Not consistent with other batteries. Figure 1 In the initial state, due to EA i With EB i In parallel, the two batteries will "naturally balance" over a period of time, so the inconsistency will be caused by EA i and EB i The two batteries share the responsibility, and the degree of inconsistency will be weakened. After the moving contact group moves, EA i With EB i-1 Parallel, EA i+1 With EB iSo now these four batteries share the aforementioned inconsistency, so the degree of inconsistency will be further reduced. Obviously, as the entire battery pack is continuously staggered in parallel, the inconsistency will spread to be evenly borne by all batteries, thus achieving dynamic balance of the entire group. This is a natural process that does not rely on any measurement and compensation. It is simple, direct, reliable, and has no additional energy loss.

[0106] Application Description:

[0107] The A set of batteries are connected in series, while the B set of batteries are separated. Therefore, in practical applications, the configuration of the A and B sets of batteries should be asymmetrical. The A set of batteries is the main battery, and its capacity should be much larger than that of the B set of batteries. The configuration of the B set of batteries focuses on the balancing function. The total capacity of the battery pack after grouping is the sum of the A and B sets of batteries.

[0108] The configuration coefficient of the two sets of batteries: B capacity / A capacity, the value of 0.02 to 0.25 is more appropriate. It is mainly to consider the range of inconsistent factory delivery and inconsistent aging of batteries, and take into account the on-current of the dislocation switch to select reasonable design parameters. The A set of batteries is fixed in series and is the main circuit of the entire battery pack, while the configuration purpose of the B set of batteries is mainly to provide the capacity required for balancing. The working current of the total circuit is the sum of the A and B sets of batteries. When the dislocation switch performs the dislocation action, the B set of batteries needs to be temporarily disconnected, and the current of the A set of batteries will fluctuate briefly at this time. In order to avoid excessive fluctuations in this gap current, a smaller B set of battery capacity should be used. The B capacity should not exceed half of the A capacity, preferably less than 25%. On the other hand, the smaller the capacity of B is, the smaller the capacity of B is, the smaller the balancing capacity it can provide. Of course, the balancing capacity is also related to the dislocation interval time of the dislocation switch. The higher the frequency of the dislocation switch action, the better the balancing effect. However, this will also cause fatigue damage to the dislocation switch itself. Therefore, this is a parameter that needs to be compromised. It is closely related to the degree of battery inconsistency, and also has a lot to do with the working current and the quality of the misaligned switch. When the working current is very small and the battery consistency is very good, a smaller configuration factor can be considered.

[0109] It should be noted that in the application documents of this patent, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "include one" do not exclude the existence of other identical elements in the process, method, article or device including the elements. In the application documents of this patent, if it is mentioned that an action is performed according to an element, it means that the action is performed at least according to the element, which includes two situations: performing the action only according to the element, and performing the action according to the element and other elements. Expressions such as multiple, multiple, and multiple include 2, 2 times, 2 kinds, and more than 2, more than 2 times, and more than 2 kinds.

[0110] All documents mentioned in this application are considered to be included in the disclosure of this application as a whole, so that they can be used as the basis for modification when necessary. In addition, it should be understood that after reading the above disclosure of this application, those skilled in the art can make various changes or modifications to this application, and these equivalent forms also fall within the scope of protection claimed in this application.

Claims

1. A battery device supporting natural equalization, characterized in that: include: An annular staggered switch, comprising N pairs of stationary contacts and M pairs of moving contacts distributed in a ring shape in a corresponding manner, wherein the N pairs of stationary contacts constitute a first annular structure and are kept in a fixed position, and the M pairs of moving contacts constitute a rotatable second annular structure, wherein N is a positive integer greater than or equal to 2, and M is a positive integer greater than 1 and less than or equal to N; A first battery pack includes N first batteries connected in series in sequence, wherein the positive and negative electrodes of the N first batteries are electrically connected to the N pairs of static contacts respectively; A second battery pack includes M second batteries that are independent of each other, wherein the M second batteries are electrically connected to the M pairs of moving contacts respectively; The annular staggered switch has N designated positions. When the second annular structure rotates to any designated position, each pair of moving contacts is electrically connected to a pair of static contacts, so that the corresponding first battery and second battery are naturally balanced by parallel connection.

2. The battery device according to claim 1, characterized in that: M=N.

3. The battery device according to claim 2, characterized in that: It also includes a driving device for driving the second annular structure to rotate from one designated position of the annular offset switch to another designated position, so that each second battery in the second battery group can be naturally balanced by being connected in parallel with different first batteries.

4. The battery device according to claim 3, characterized in that: The driving device includes a motor and a controller; The controller is used to control the motor to periodically drive the second annular structure to rotate from a specified position of the annular offset switch to the next specified position, and stay at each specified position for a predetermined period of time, so that each second battery in the second battery group is connected in parallel with each first battery in the first battery group to achieve natural balance.

5. The battery device according to claim 1, characterized in that: The single cell capacity of the first battery group is greater than the single cell capacity of the second battery group.

6. The battery device according to claim 1, characterized in that: The value range of the single cell capacity of the second battery group / the single cell capacity of the first battery group is 0.02 to 0.

25.

7. The battery device according to claim 2, characterized in that: The N pairs of static contacts are evenly arranged in a ring shape on the first ring structure; The M pairs of moving contacts are evenly arranged in a ring shape on the second ring structure.

8. The battery device according to claim 7, characterized in that: The first annular structure and the second annular structure are coaxial, and the second annular structure is rotatable around the axis.

9. The battery device according to claim 8, characterized in that: It also includes lead-out electrodes for leading out the positive and negative electrodes of the first battery pack and electrically connecting them to an external power-consuming device or a charging device.

10. The battery device according to claim 1, characterized in that: The capacity of the storage battery device is the sum of the capacities of all batteries in the first battery group and the second battery group.

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