A sodium-ion and lithium-ion battery mixed battery pack

Abstract

The present disclosure relates to a sodium-ion and lithium-ion battery mixed battery pack, which comprises a lithium battery module, a sodium battery module, a first DCDC module, a second DCDC module and a master control module. The lithium battery module comprises a lithium-ion battery cell assembly and a heating film arranged on one side of the lithium-ion battery cell assembly. The sodium battery module comprises a sodium-ion battery cell assembly. The lithium battery module supplies power to the sodium battery module through the first DCDC module. The master control module monitors the state of the lithium battery module and the sodium battery module and performs charge and discharge management. The sodium-ion and lithium-ion battery mixed battery pack provided by the present disclosure realizes energy complementation and low-temperature guarantee through the cooperative work of the two battery modules. The sodium battery module heats the lithium battery module at low temperature, and the lithium battery module supplies power to the sodium battery module, thereby improving the adaptability to extreme environments.

Description

Technical Field

[0001] This disclosure relates to the field of battery technology, and in particular to a battery pack that combines sodium-ion and lithium-ion batteries. Background Technology

[0002] With the rapid development of electric vehicles and energy storage systems, higher demands are being placed on the energy density, safety, and reliability of battery packs. Traditional single-type battery packs (such as pure lithium battery packs) have limitations in certain aspects, such as cost, resource constraints, and low-temperature performance. Sodium-ion batteries, as an emerging battery technology, have advantages such as abundant resources, low cost, and high safety, but they still lag behind lithium-ion batteries in terms of energy density and cycle life. Therefore, combining sodium-ion batteries with lithium-ion batteries to form hybrid battery packs can combine the advantages of both and improve the overall performance of the battery pack. However, existing hybrid battery packs still face many challenges in terms of structural design, energy management, and thermal management. Utility Model Content

[0003] To address the aforementioned technical issues, this disclosure provides a hybrid battery pack combining sodium-ion and lithium-ion batteries. By combining lithium battery modules and sodium battery modules, the energy density and range of the hybrid battery pack are improved.

[0004] In a first aspect, embodiments of this disclosure provide a hybrid battery pack for sodium-ion and lithium-ion batteries. The hybrid battery pack includes: a lithium battery module, a sodium battery module, a first DC-DC converter module, a second DC-DC converter module, and a main control module. The main control module is connected to both the lithium battery module and the sodium battery module. The sodium battery module includes sodium-ion cell components, which are connected to a heating film.

[0005] The lithium battery module includes a lithium-ion battery cell assembly and a heating film, the heating film being disposed on at least one side of the lithium-ion battery cell assembly. The input terminal of a first DC-DC module is electrically connected to the lithium battery module, and the output terminal of the first DC-DC module is electrically connected to the sodium battery module. The lithium battery module is used to transmit electrical energy to the sodium battery module through the first DC-DC module.

[0006] The input of the second DC-DC module is connected to the sodium-ion battery assembly, and the output of the second DC-DC module is connected to the main control module. The sodium battery module is used to control the sodium-ion battery assembly to transmit electrical energy to the main control module through the second DC-DC module in response to activation signals from external devices.

[0007] In some embodiments, the sodium battery module further includes a protection board module, which is connected in series with the sodium-ion battery cell assembly and connected to the main control module. The protection board module is used to collect at least one of the temperature, voltage, and current information of each sodium-ion battery cell in the sodium-ion battery cell assembly and transmit the collected information to the main control module.

[0008] In some embodiments, the sodium-ion and lithium-ion hybrid battery pack further includes a communication connector, which is connected to the main control module and the protection board module. The communication connector is also used to connect to external electrical equipment. When the communication connector is connected to the external electrical equipment, the protection board module is used to switch to the working state in response to an activation signal from the external device and control the second DC-DC module to output power to the main control module.

[0009] In some embodiments, the protection board module includes a switching element, a first end of which is connected to the sodium battery module, and the other end of which is used to connect to an external load. The switching element is configured to close when the voltage, temperature, and current of the sodium-ion battery cell are all below a set threshold, and to open when at least one of the voltage, temperature, and current of the sodium-ion battery cell is greater than or equal to the set threshold.

[0010] In some embodiments, the protection board module includes a first fuse, a first end of which is connected to the sodium battery module, and the other end of which is connected to an external load. The first fuse is used to blow in the event of a short circuit or continuous overcurrent in the sodium battery module.

[0011] In some embodiments, the lithium battery module includes at least two lithium-ion cell assemblies connected in series and a manual maintenance switch, the manual maintenance switch having a built-in second fuse.

[0012] In some embodiments, the lithium battery module further includes a slave control module connected to the master control module. The slave control module is used to collect at least one of the temperature information and voltage information of each lithium-ion cell in the lithium-ion cell assembly, and transmit the collected information to the master control module.

[0013] In some embodiments, the sodium-ion and lithium-ion battery pack further includes an electric heating module, which includes a heating relay and a heating fuse. The heating relay and the heating fuse are connected in series between the negative electrode of the sodium battery module and the negative electrode of the heating film. The positive electrode of the heating film is connected to the positive electrode of the sodium battery module to form a first heating circuit.

[0014] In some embodiments, the sodium-ion and lithium-ion battery pack further includes a charging connector and a charging relay. The charging connector is used to connect to an external power source. The positive terminal of the charging connector is connected in sequence to the positive terminal of the heating film via the charging relay, the positive terminal of the input terminal of the first DC-DC module, the positive terminal of the output terminal of the first DC-DC module, and the negative terminal of the heating film is connected to the negative terminal of the charging connector, forming a second heating circuit.

[0015] In some embodiments, the sodium-ion and lithium-ion battery pack further includes a BDU module, a charging relay, and a charging connector. The BDU module is connected to the main control module. The positive terminal of the lithium battery module is connected to the positive interface of the charging connector through the charging relay, and the negative terminal of the lithium battery module is connected to the negative interface of the charging connector through the main negative relay.

[0016] In some embodiments, the BDU module includes: a main positive relay and / or a main negative relay. A first terminal of the main positive relay is connected to the positive terminal of the lithium battery module, and a second terminal of the main positive relay is used to connect to the positive terminal of an external load. A first terminal of the main negative relay is connected to the negative terminal of the lithium battery module, and a second terminal of the main negative relay is used to connect to the negative terminal of an external load.

[0017] In some embodiments, the BDU module further includes a precharge relay and a precharge resistor, wherein the precharge relay and the precharge resistor are connected in series and then in parallel to the two ends of the main positive relay.

[0018] In some embodiments, the sodium-ion and lithium-ion battery pack further includes a first positive discharge connector and a first negative discharge connector. A first end of the first positive discharge connector is connected to the positive terminal of the lithium battery module via a main positive relay, and a second end of the first positive discharge connector is used to connect to the positive terminal of an external electrical device. A first end of the first negative discharge connector is connected to the negative terminal of the lithium battery module via a main negative relay and a current transformer, and a second end of the first negative discharge connector is used to connect to the negative terminal of an external electrical device.

[0019] In some embodiments, the sodium-ion and lithium-ion battery pack further includes a second discharge connector, the positive terminal of which is connected to the positive terminal of the sodium battery module, and the negative terminal of which is connected to the negative terminal of the sodium battery module.

[0020] In some embodiments, the sodium-ion and lithium-ion battery pack further includes a current transformer connected in series with a main negative relay and connected to the main control module. The negative terminal of the charging connector is connected to the negative terminal of the lithium battery module through the current transformer and the main negative relay.

[0021] Secondly, embodiments of this disclosure provide an electrical device, including: a battery pack that combines sodium-ion and lithium-ion batteries as provided in any of the foregoing embodiments.

[0022] The advantages of this disclosure are: 1. By combining lithium-ion and sodium-ion battery modules, the dual-module design achieves high integration and complementary performance and functions, improving the energy density and range of the hybrid sodium-ion and lithium-ion battery pack, and providing energy complementarity and low-temperature protection. The sodium-ion battery module provides heating for the lithium-ion battery module at low temperatures, while the lithium-ion battery module replenishes the sodium-ion battery module, enhancing adaptability to extreme environments. The lithium-ion battery module can also replenish the sodium-ion battery module and power external devices, while the sodium-ion battery module can both drive external devices and power low-voltage electrical components within the hybrid sodium-ion and lithium-ion battery pack, demonstrating strong functional reusability.

[0023] 2. The first DC-DC module enables the lithium battery module to replenish the sodium battery module, thereby improving energy utilization efficiency.

[0024] 3. The system power-on process is highly simplified. After the external device sends an activation signal, the protection board module immediately responds and controls the second DC-DC module to supply power to the main control module, realizing the rapid activation of the entire system and enabling it to immediately enter the normal charging, discharging, heating and other working states. This not only ensures the accuracy of startup, but also greatly improves the convenience of operation and the efficiency of emergency response.

[0025] 4. The main control module can monitor the operating status of the mixed sodium-ion and lithium-ion battery pack in real time and perform charge and discharge management, which improves the safety and reliability of the mixed sodium-ion and lithium-ion battery pack. Attached Figure Description

[0026] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0027] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a structural diagram of a battery pack that combines sodium-ion and lithium-ion batteries according to an embodiment of the present disclosure; Figure 2 This is an exploded structural diagram of a sodium-ion and lithium-ion battery pack according to an embodiment of the present disclosure; Figure 3 This is a circuit diagram of a battery pack that uses a combination of sodium-ion and lithium-ion batteries according to an embodiment of the present disclosure.

[0029] Figure label: 1. Lithium battery module; 11. Heating film; 12. First end plate; 13. First CCS assembly; 14. Slave control module; 2. Sodium battery module; 21. Second end plate; 22. Protection board module; 23. Second CCS assembly; 3. BDU module; 31. Main positive relay; 32. Main negative relay; 33. Charging relay; 34. Pre-charge relay; 35. Pre-charge resistor; 36. Current transformer; 4. First DC-DC module; 5. Second DC-DC module; 6. Electric heating module; 61. Heating relay; 62. Heating fuse; 7. Main control module; 8. Lower housing; 81. Liquid cooling assembly; 82. Manual maintenance switch; 83. First discharge positive connector; 84. First discharge negative connector; 85. Second discharge connector; 86. Charging connector; 87. Communication connector; 9. Top cover. Detailed Implementation

[0030] To better understand the above-mentioned objectives, features, and advantages of this disclosure, the solutions disclosed herein will be further described below. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0031] Numerous specific details are set forth in the following description in order to provide a full understanding of this disclosure, but this disclosure may also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only some, and not all, of the embodiments of this disclosure.

[0032] This disclosure provides a hybrid battery pack and electrical device that uses both sodium-ion and lithium-ion batteries. The following describes the hybrid battery pack and electrical device with reference to specific embodiments.

[0033] Figure 1 This is a structural diagram of a hybrid sodium-ion and lithium-ion battery pack according to an embodiment of this disclosure. Figure 2 This is an exploded structural diagram of a sodium-ion and lithium-ion hybrid battery pack according to an embodiment of this disclosure. Figure 3 This is a circuit diagram of a battery pack that uses a combination of sodium-ion and lithium-ion batteries according to an embodiment of the present disclosure.

[0034] The sodium-ion and lithium-ion hybrid battery packs provided in this disclosure can be applied to the fields of new energy vehicles and energy storage (such as grid-scale energy storage, residential energy storage, and industrial and commercial energy storage). It is understood that the sodium-ion and lithium-ion hybrid battery packs provided in this disclosure can also be applied in other scenarios.

[0035] The electrical equipment can specifically be a means of transportation, such as household electric / hybrid vehicles, commercial electric / hybrid vehicles (logistics vehicles, heavy trucks, buses, etc.), and electric / hybrid motorcycles.

[0036] like Figure 1 and Figure 2 As shown, this disclosure provides a hybrid battery pack for sodium-ion and lithium-ion batteries, comprising a lithium battery module 1 and a sodium battery module 2. The lithium battery module 1 includes a plurality of (one or two or more) lithium-ion cells, and the sodium battery module 2 includes a plurality of (one or two or more) sodium-ion cells.

[0037] Sodium-ion battery cells operate at a lower voltage than lithium-ion battery cells. Based on this, lithium battery module 1 can be used as a high-voltage power supply module, and sodium battery module 2 can be used as a low-voltage power supply module.

[0038] By integrating a lithium battery module 1 and a sodium battery module 2 into a hybrid sodium-ion and lithium-ion battery pack, the hybrid sodium-ion and lithium-ion battery pack can achieve both high-voltage and low-voltage output.

[0039] Lithium battery module 1 uses lithium-ion cells with higher operating voltage, which is naturally suitable for high-voltage power supply requirements (such as power drive systems); sodium battery module 2 uses sodium-ion cells with lower operating voltage, which is precisely matched to low-voltage power supply requirements (such as control units and auxiliary electronic devices). Sodium battery module 2 can achieve high-rate charging and discharging through its high-power sodium ions, thereby providing a stable power supply for external electrical equipment and internal low-voltage control units.

[0040] If a single high-voltage module is used for power supply, an additional step-down module is required to meet the low-voltage demand, resulting in energy loss and space occupation issues. If a single low-voltage module is used, it cannot meet the high-voltage power output demand. The sodium-ion and lithium-ion battery pack provided in this embodiment integrates two battery modules, allowing the corresponding battery modules to directly handle the two types of voltage output demands, structurally eliminating the cumbersome design of step-down devices or multiple pack combinations.

[0041] In some embodiments, such as Figure 1 and Figure 2 As shown, the sodium-ion and lithium-ion battery pack also includes a lower housing 8 and an upper cover 9. The components of the sodium-ion and lithium-ion battery pack are located in the sealed space formed by the lower housing 8 and the upper cover 9, and at least a portion of the components of the sodium-ion and lithium-ion battery pack are fixedly connected to the lower housing 8.

[0042] For example, the lithium battery module 1 is fixed to the lower housing 8 by bolts and thermally conductive structural adhesive. For instance, thermally conductive structural adhesive is provided on one outer side wall of the lithium battery module 1, and the outer side wall is bonded to the inner wall of the lower housing 8 by the thermally conductive adhesive structure; at the same time, the lithium battery module 1 is also fixed to the side wall of the lower housing 8 by bolt assemblies.

[0043] In this way, the lithium battery module 1 is double-fixed by thermally conductive structural adhesive and bolts, which can ensure structural stability. In addition, the thermally conductive structural adhesive can also achieve good heat transfer, thereby improving the heat dissipation effect of the lithium battery module 1.

[0044] For example, the sodium battery module 2 is fixed to the lower housing 8 by bolts and thermally conductive structural adhesive. For instance, thermally conductive structural adhesive is provided on one outer side wall of the sodium battery module 2, and this outer side wall is bonded to the inner wall of the lower housing 8 by the thermally conductive adhesive structure; at the same time, the sodium battery module 2 is also fixed to the inner wall of the lower housing 8 by bolt assemblies.

[0045] In this way, the sodium battery module 2 is double-fixed by thermally conductive structural adhesive and bolts, which can ensure structural stability. Furthermore, the thermally conductive structural adhesive can also achieve good heat transfer, thereby improving the heat dissipation effect of the sodium battery module 2.

[0046] In some embodiments, such as Figure 1 and Figure 2 As shown, the lithium battery module 1 includes at least two lithium-ion cell assemblies. The at least two lithium-ion cell assemblies included in the lithium battery module 1 can be both connected in series, or some of the lithium-ion cell assemblies can be connected in series and some of the series-connected assemblies can be connected in parallel.

[0047] The lithium battery module 1 includes lithium-ion battery cell components that can be connected in series or in combination with some series and some parallel connections. With the series / parallel design of multiple lithium-ion battery cells within a single lithium-ion battery cell component, the output voltage and capacity of the entire lithium battery module 1 can be flexibly adjusted (e.g., series connection to increase voltage, parallel connection to increase capacity). Without redesigning the overall structure of the lithium battery module 1, it can meet diverse power needs from low power to high power and from low capacity to high capacity.

[0048] Meanwhile, this two-stage flexible connection design of the cell assembly and battery module also improves the practicality and maintenance convenience of lithium battery module 1. The modularization of lithium-ion cells makes the lithium-ion cell layout more orderly. If a certain lithium-ion cell assembly or a certain lithium-ion cell fails, it can be repaired or replaced accordingly without replacing the entire lithium battery module 1. Moreover, through reasonable series and parallel combinations, the charging and discharging states of each lithium-ion cell can be balanced to a certain extent, indirectly ensuring the overall power supply stability of lithium battery module 1 and reducing the risk of a single cell problem affecting the whole system.

[0049] For example, each lithium-ion battery cell assembly includes at least one lithium-ion battery cell. When a lithium-ion battery cell assembly includes multiple lithium-ion battery cells, the multiple lithium-ion battery cells included in the lithium-ion battery cell assembly are connected in series and / or in parallel.

[0050] For example, a lithium-ion battery cell assembly includes two lithium-ion cells, which can be connected in series or in parallel.

[0051] For example, if a lithium-ion battery cell assembly includes three lithium-ion cells, then these three lithium-ion cells can all be connected in parallel; or, two of the lithium-ion cells can be connected in series and then connected in parallel with another lithium-ion cell.

[0052] The same principle applies when a lithium-ion battery assembly includes a larger number of lithium-ion cells, and will not be elaborated further here.

[0053] In some embodiments, such as Figure 2 and Figure 3 As shown, the lithium-ion battery cell assembly also includes a first end plate 12 and a first CCS assembly 13. The lithium-ion cells included in the lithium-ion battery cell assembly are connected to each other via the first CCS assembly 13. The first end plate 12 is disposed on at least two opposite sides of each lithium-ion cell included in the lithium-ion battery cell assembly. By applying a certain preload to the first end plate 12, the lithium-ion cells and the first CCS assembly 13, among other structures, are fixed within the lithium-ion battery cell assembly.

[0054] For example, the CCS component described in this disclosure embodiment may be a cell connection system.

[0055] The first CCS module 13 can effectively connect each lithium-ion cell to build a stable power transmission path, providing a necessary and continuous electrical connection foundation for the charging and discharging of the first CCS module 13, and avoiding electrical performance interruption or failure caused by improper decentralized connection of lithium-ion cells.

[0056] The first end plate 12 fixes each lithium-ion cell from opposite sides of the lithium-ion cell assembly. This not only firmly binds each lithium-ion cell to the first CCS assembly 13, but also prevents external structures from bumping into the lithium-ion cells, preventing components from loosening or shifting, indirectly reducing safety hazards caused by structural loosening, and improving the overall long-term durability of the assembly.

[0057] In some embodiments, such as Figure 2 and Figure 3 As shown, the lithium battery module 1 also includes a heating film 11, which is disposed on at least one side of the lithium-ion battery cell assembly. The sodium battery module 2 is connected to the heating film 11.

[0058] For example, the heating film 11 may be adhered to at least one side of the lithium-ion battery cell assembly.

[0059] For example, if the lithium-ion battery cell assembly is roughly rectangular, then the heating film 11 can be disposed on one side wall of the lithium-ion battery cell assembly, or on two opposite side walls of the lithium-ion battery cell assembly, or disposed around the side walls of the lithium-ion battery cell assembly.

[0060] Based on this, the heating film 11 can also be located at the end of the lithium-ion battery cell assembly (the top and / or bottom of the cuboid).

[0061] The sodium battery module 2 is used to supply power to the heating film 11 when the temperature of the lithium battery module 1 is lower than a set threshold, so as to heat the lithium-ion battery cell assembly and avoid abnormal power supply caused by the lithium-ion battery cell assembly being too cold.

[0062] For example, at least one sodium-ion battery cell assembly in the sodium battery module 2 is connected to the heating film 11 to supply power to the heating film 11.

[0063] The sodium-ion battery cell assembly is used to supply power to the heating film 11 to heat the lithium-ion battery cell assembly when the temperature of the lithium-ion battery cell assembly is lower than a set threshold, thereby preventing the lithium-ion battery cell assembly from being unable to supply power normally due to excessively low temperature.

[0064] The sodium-ion battery cell assembly is also used to disconnect from the heating film 11 when the temperature of the lithium-ion battery cell assembly is greater than or equal to a set threshold, that is, to stop supplying power to the heating film 11, thereby avoiding safety risks caused by excessive temperature of the lithium-ion battery cell assembly.

[0065] In this embodiment, the cooperation between the heating film 11 and the sodium-ion battery module enables adaptive temperature control of the lithium-ion battery module, significantly improving its operational reliability and safety. When the temperature of the lithium-ion battery module is below a set threshold, the sodium-ion battery module supplies power to the heating film 11, effectively preventing the lithium-ion battery module from failing due to low temperatures and ensuring that it can still supply power normally in low-temperature environments, thus enhancing its low-temperature adaptability. Simultaneously, when the temperature of the lithium-ion battery module reaches or exceeds the threshold, the sodium-ion battery module disconnects from the heating film 11, preventing overheating and excessively high temperatures in the lithium-ion battery module. This reduces the safety risks caused by overheating from the source, forming a closed-loop control of "low-temperature protection - high-temperature protection," improving the overall stability of the hybrid sodium-ion and lithium-ion battery pack.

[0066] In some embodiments, the sodium battery module 2 includes at least one sodium-ion battery cell assembly.

[0067] For example, each sodium-ion battery assembly includes at least one sodium-ion battery cell. When the sodium-ion battery assembly includes multiple sodium-ion battery cells, the multiple sodium-ion battery cells in the sodium-ion battery assembly are connected in series and / or in parallel.

[0068] The connection method of each sodium-ion cell in the sodium-ion battery cell assembly and the corresponding technical effects are described in the previous section on lithium-ion battery cell assemblies, and will not be repeated here.

[0069] In some embodiments, such as Figure 2 and Figure 3 As shown, the sodium-ion battery assembly also includes a second end plate 21 and a second CCS assembly 23. The sodium-ion batteries in the assembly are connected to each other via the second CCS assembly 23. The second end plate 21 is disposed on at least two opposite sides of each sodium-ion battery in the assembly, and a certain preload is applied to the second end plate 21 to fix the sodium-ion batteries and the second CCS assembly 23 within the assembly.

[0070] In this embodiment, the cooperation between the second CCS component 23 and the second end plate 21 effectively ensures the electrical performance and structural stability of the sodium-ion battery cell assembly. The second CCS component 23 achieves reliable connection of each sodium-ion battery cell, establishing a stable power transmission path and providing the necessary electrical connection foundation for the charging and discharging of the second battery module 2, avoiding electrical performance interruption due to sodium-ion battery cell connection failure. At the same time, the second end plate 21 fixes each sodium-ion battery cell assembly on opposite sides of the sodium-ion battery cells, which not only firmly constrains the sodium-ion battery cell assembly and the second CCS component 23, but also prevents the sodium-ion battery cells from being bumped by external structures, preventing the assembly from loosening and shifting, indirectly reducing the safety risks caused by structural loosening, and improving the long-term durability of the entire battery cell assembly.

[0071] In some embodiments, the sodium-ion and lithium-ion battery pack further includes a first DC-DC module 4, the input of which is electrically connected to the lithium battery module 1, and the output of which is electrically connected to the sodium battery module 2. The lithium battery module 1 is used to transmit electrical energy to the sodium battery module 2 through the first DC-DC module 4.

[0072] For example, the first DC-DC module 4 integrates high and low voltage control and soft-start units.

[0073] The positive and negative terminals of lithium battery module 1 are connected to the input terminals of the first DC-DC module 4, respectively, and the positive and negative terminals of sodium battery module 2 are connected to the output terminals of the first DC-DC module 4, respectively, so that lithium battery module 1 can replenish the energy of sodium battery module 2.

[0074] The main control module 7 communicates with the protection board module 22 and the first DC-DC module 4. The main control module 7 is used to monitor the operating status of the sodium battery module 2, send the operating mode to the first DC-DC module 4, and feed back the temperature information of the lithium battery module 1 to the protection board module 22.

[0075] Through the cooperation of the first DC-DC module 4 and the main control module 7, reliable regulation and safety assurance of energy transfer between the lithium battery module 1 and the sodium battery module 2 are achieved. On the one hand, the first DC-DC module 4, as an energy transfer bridge, can convert and adapt to the possible voltage differences between the lithium battery module 1 and the sodium battery module 2, ensuring stable power supply from the lithium battery module 1 to the sodium battery module 2. Its integrated soft-start unit can also avoid the inrush current during startup, protecting the lithium battery module 1 and the sodium battery module 2 from damage.

[0076] On the other hand, the main control module 7 can monitor the status of the sodium battery module 2 in real time and dynamically issue working modes through communication with the protection board module 22 and the first DCDC module 4. At the same time, it can feed back the temperature of the lithium battery module 1 to the protection board module 22, forming a closed loop of "status monitoring - command control - safety feedback". This ensures that energy replenishment is carried out as needed, and can prevent safety risks such as overheating through real-time interaction of parameters such as temperature, thereby improving the overall operational stability and safety of the mixed sodium-ion and lithium-ion battery pack.

[0077] In some embodiments, such as Figure 2 and Figure 3 As shown, the hybrid sodium-ion and lithium-ion battery pack also includes a second DC-DC module 5. The input of the second DC-DC module 5 is connected to the sodium-ion battery cell assembly, and the output of the second DC-DC module 5 is connected to the main control module 7. The sodium battery module 2 is used to control the sodium-ion battery cell assembly to transmit electrical energy to the main control module 7 through the second DC-DC module 5 in response to an activation signal from an external device.

[0078] Through the cooperation of the second DC-DC module 5 and the sodium battery module 2, a precise and controllable energy supply is provided to the main control module 7. On the one hand, the second DC-DC module 5 can realize voltage conversion, adapting the output voltage of the sodium-ion battery module to the operating voltage required by the main control module 7, avoiding damage to the main control module 7 due to voltage mismatch and ensuring its stable operation. On the other hand, the power supply process is triggered by the "external device activation signal," meaning that the main control module 7 is only powered by the sodium-ion battery module when needed (such as when an external device wakes up the sodium-ion and lithium-ion battery pack). Normally, it can be in a power-off or low-power state, effectively reducing the ineffective power consumption of the sodium-ion battery module and improving energy utilization efficiency. At the same time, this "external activation-on-demand power supply" logic allows the startup of the sodium-ion and lithium-ion battery pack to be linked to the needs of external devices, enhancing the orderliness and responsiveness of system control, and indirectly improving the overall operating efficiency and reliability of the sodium-ion and lithium-ion battery pack.

[0079] In some embodiments, such as Figure 1 , Figure 2 and Figure 3 As shown, the battery pack that combines sodium-ion and lithium-ion batteries also includes a main control module 7, which is connected to the lithium battery module 1 and the sodium battery module 2.

[0080] When the main control module 7 detects that the SOC (State of Charge) or the individual cell voltage (voltage of a single lithium-ion cell) of the lithium battery module 1 is lower than a certain threshold, it issues an alarm signal to prompt the user to charge.

[0081] When the main control module 7 detects that the SOC or single cell voltage (voltage of a single sodium-ion cell) of the sodium battery module 2 is lower than a certain threshold, it replenishes the sodium battery.

[0082] By monitoring and controlling the status of lithium battery module 1 and sodium battery module 2 through the main control module 7, intelligent management of the mixed sodium-ion and lithium-ion battery pack is achieved. On the one hand, when the SOC or single-cell voltage of lithium battery module 1 is too low, the main control module 7 issues an alarm to prompt charging, which can promptly prevent cell damage caused by over-discharge of lithium battery module 1 and extend its service life.

[0083] On the other hand, when the sodium battery module 2 is low on power, the main control module 7 triggers (lithium battery module 1 to replenish the sodium battery module 2) to ensure that the sodium battery module 2 always maintains within the effective working power range, ensuring the stability of its function as an auxiliary power supply unit (such as driving the heating film, supplying power to the main control module, etc.), and avoiding the failure of key auxiliary functions of the system due to the failure of the sodium battery module 2.

[0084] Overall, this "status monitoring-tiered response" mechanism forms a closed-loop management system for lithium battery module 1 and sodium battery module 2, which not only protects the performance of the cells but also improves the overall stability and safety of the mixed sodium-ion and lithium-ion battery pack.

[0085] In some embodiments, the sodium battery module 2 further includes a protection board module 22, which is connected in series with the sodium-ion battery cell assembly and to the main control module 7. The protection board module 22 is used to collect / monitor at least one of the temperature, voltage, and current information of each sodium-ion battery cell in the sodium-ion battery cell assembly, and transmit the collected information to the main control module 7.

[0086] For example, the sodium battery module 2 is connected to the protection board module 22 via a copper busbar / wiring harness. The protection board module 22 is responsible for collecting / monitoring information such as voltage, temperature, and current of each sodium-ion cell in the second battery module 2.

[0087] The protection board module 22 collects key information such as temperature, voltage, and current of the sodium-ion battery cell assembly and transmits it to the main control module 7, forming the basis for refined state perception and monitoring of the sodium battery module 2. On the one hand, the real-time collected cell parameters provide data support for assessing the health status and charge / discharge status of the sodium-ion battery cell, and can promptly detect abnormal conditions such as overvoltage, undervoltage, overtemperature, and overcurrent, providing a basis for subsequent safety protection (such as power failure protection) or regulation (such as energy replenishment control).

[0088] On the other hand, after this information is transmitted to the main control module 7, it can help the main control module 7 to more accurately judge the operating status of the sodium battery module 2, ensure its stability when supplying power to the heating film 11, the main control module 7, etc., and avoid the failure of auxiliary functions due to abnormal sodium-ion cell status, thereby improving the operating safety and reliability of the sodium battery module 2 and even the entire sodium-ion and lithium-ion battery pack.

[0089] In some embodiments, such as Figure 2 and Figure 3 As shown, the sodium-ion and lithium-ion hybrid battery pack also includes a communication connector 87, which is connected to the main control module 7 and the protection board module 22. The communication connector 87 is also used to connect to external electrical equipment. When the communication connector 87 is connected to external electrical equipment, the protection board module 22 is used to switch to the working state in response to the activation signal from the external device and control the second DC-DC module 5 to output power to the main control module 7.

[0090] The main control module 7 and the protection board module 22 are connected to external electrical equipment through the communication connector 87. The protection board module 22 is turned on by shorting the low voltage activation signal of the external protection board module 22. The main control module 7 is powered and activated through the second DC-DC module 5. All components in the sodium-ion and lithium-ion battery pack are in an activated state.

[0091] Through the cooperation of communication connector 87, protection board module 22, and main control module 7, the orderly interaction and precise activation of the sodium-ion and lithium-ion battery pack with external electrical equipment are achieved. The communication connector, acting as an intermediate hub, establishes a communication channel between external electrical equipment and the internal modules of the sodium-ion and lithium-ion battery pack, and provides a reliable path for activation signal transmission, ensuring the stability of internal and external interaction. The activation signal from the external device triggers the protection board module 22 to switch its operating state and controls the second DC-DC module 5 to supply power to the main control module 7, forming an orderly process of "external wake-up - internal response - step-by-step activation." This ensures that each component of the sodium-ion and lithium-ion battery pack starts up as needed, avoiding ineffective energy consumption during periods of inactivity and improving energy utilization efficiency. The external short-circuit activation method is simple and direct, and is suitable for the need to quickly wake up the mixed sodium-ion and lithium-ion battery packs in practical applications. At the same time, through the collaboration of the protection board module 22 and the main control module 7, it ensures that the components in each mixed sodium-ion and lithium-ion battery pack work together after activation, laying the foundation for subsequent power supply, status monitoring and other functions, and improving the compatibility of the mixed sodium-ion and lithium-ion battery pack with external devices and the controllability of system operation.

[0092] In some embodiments, the protection board module 22 includes a switching element, a first end of which is connected to the sodium battery module 2, and the other end of which is used to connect to an external load. The switching element is used to close when the voltage, temperature, and current of the sodium-ion battery cell are all less than a set threshold, and to open when at least one of the voltage, temperature, and current of the sodium-ion battery cell is greater than or equal to the set threshold.

[0093] For example, the switching element is used to control the on / off state of the charging and discharging circuit of the sodium battery module 2. The switching element can be a MOS switch or a relay, etc.

[0094] In some embodiments, the protection board module 22 includes a first fuse, a first end of which is connected to the sodium battery module 2, and the other end of which is used to connect to an external load. The first fuse is used to blow in the event of a short circuit or continuous overcurrent in the sodium battery module 2.

[0095] The protection board module 22 has a built-in fuse for short-circuit and overcurrent protection of the sodium battery module 2.

[0096] The protection board module 22 constructs a multi-layered safety protection system for the sodium battery module 2 through the coordinated design of switching elements and the first fuse. On the one hand, the switching elements can dynamically control the opening and closing of the charging and discharging circuit in real time according to the voltage, temperature and current parameters of the sodium-ion battery cell. Under normal conditions, the circuit is closed to ensure smooth operation. When any parameter exceeds the standard, it is immediately disconnected to quickly block abnormal charging and discharging, avoiding cell damage or performance degradation caused by overvoltage, overtemperature and overcurrent, thus achieving active and precise real-time protection.

[0097] On the other hand, the first fuse, as a supplement to passive protection, melts and cuts off the circuit in the event of a short circuit or continuous overcurrent (which may exceed the response range of the switching element), forming a dual line of defense of "active control + passive fuse". This effectively prevents safety risks caused by extreme faults (such as fire or explosion) while protecting external loads from abnormal current surges. This ensures the circuit reliability of the sodium battery module 2 during normal operation and significantly improves its safety under abnormal operating conditions through graded protection, thereby enhancing the overall system stability.

[0098] In some embodiments, such as Figure 2 and Figure 3 As shown, the lithium battery module 1 includes at least two lithium-ion battery cell assemblies connected in series and a manual maintenance switch 82, which has a built-in second fuse.

[0099] For example, the manual service switch 82 may be an MSD (Manual Service Disconnect). The lithium battery module 1 is connected to the manual service switch 82 via a copper busbar / wiring harness.

[0100] At least two lithium-ion battery cells in lithium battery module 1 are connected in series to form a high-voltage power supply. A manual maintenance switch 82 is connected in series between the lithium-ion battery cells. The manual maintenance switch 82 is disconnected when the equipment is being repaired to ensure the personal safety of the maintenance personnel.

[0101] For example, the manual maintenance switch 82 is equipped with a fuse to provide overcurrent and short-circuit protection for the lithium battery module 1.

[0102] The manual maintenance switch 82, with its dual design of manual disconnection and fuse protection, provides crucial safety and operational convenience for the lithium battery module 1. On the one hand, as a manual disconnection device connected in series in the high-voltage circuit, pulling out the manual maintenance switch 82 during maintenance directly cuts off the high-voltage power circuit formed by the series-connected lithium-ion battery cell assembly, physically isolating the high voltage and completely avoiding the risk of maintenance personnel coming into contact with high-voltage electricity, thus ensuring the personal safety of maintenance personnel during the maintenance process.

[0103] On the other hand, the second fuse built into the manual maintenance switch 82 can blow in the event of extreme faults such as overcurrent or short circuit in the lithium battery module 1, quickly cutting off the circuit and preventing the fault from escalating to damage the battery cell assembly or causing a more serious safety accident, thus forming passive protection for the lithium battery module 1. This combination of active operation disconnection and passive fault fuse not only meets the maintenance needs of the high-voltage battery module but also strengthens safety protection under abnormal operating conditions, significantly improving the safety and ease of maintenance of the lithium battery module 1.

[0104] In some embodiments, such as Figure 2 and Figure 3 As shown, the lithium battery module 1 also includes a slave control module 14, which is connected to the master control module 7. The slave control module 14 is used to collect at least one of the temperature information and voltage information of each lithium-ion cell in the lithium-ion cell assembly, and transmit the collected information to the master control module 7.

[0105] The slave control module 14 collects key information such as temperature and voltage of the lithium-ion battery cell components and transmits it to the master control module 7, providing accurate data support for the status monitoring of the lithium battery module 1. On the one hand, the slave control module 14 is responsible for collecting parameters of the lithium-ion battery cells, and can capture the operating status of each cell in real time (such as whether it is over-temperature or under-voltage), ensuring that the master control module 7 can fully grasp the detailed status of the lithium battery module 1, providing a reliable basis for subsequent alarms (such as when the SOC or voltage is too low) and regulation operations. On the other hand, this division of labor mode of slave control acquisition and master control decision-making not only reduces the direct acquisition burden of the master control module 7, but also improves the relevance and accuracy of information acquisition, avoiding misjudgment of the status of the lithium battery module 1 due to missing or delayed information, thereby indirectly ensuring its operational safety, extending its service life, and enhancing the collaborative efficiency of the entire sodium-ion and lithium-ion battery pack monitoring system.

[0106] In some embodiments, such as Figure 2 and Figure 3 As shown, the battery pack for both sodium-ion and lithium-ion batteries also includes an electric heating module 6. The electric heating module 6 includes a heating relay 61 and a heating fuse 62. The heating relay 61 and the heating fuse 62 are connected in series between the negative electrode of the sodium battery module 2 and the negative electrode of the heating film 11. The positive electrode of the heating film 11 is connected to the positive electrode of the sodium battery module 2 to form a first heating circuit.

[0107] The negative electrode of the sodium battery module 2 is connected to the negative electrode of the heating film 11 through the protection board module 22, the heating relay 61 and the heating fuse 62 in the electric heating module 6, and the positive electrode of the sodium battery module 2 is connected to the positive electrode of the heating film 11, forming a heating circuit to enable the sodium battery module 2 to heat the lithium battery module 1 in a low-temperature environment.

[0108] The heating fuse 62 in heating module 6 provides overcurrent and short-circuit protection for the heating circuit. Electric heating module 6 is connected to sodium battery module 2 and heating film 11 via copper busbars / wiring harnesses.

[0109] The protection board module 22 receives the temperature information of the lithium battery module 1 monitored by the main control module 7, and controls the heating relay 61 to close to heat the lithium battery module 1. When the main control module 7 detects that the external environment is below a certain temperature threshold and the lithium battery module 1 cannot work normally, it controls the heating relay 61 to close to heat the lithium battery module 1. When the temperature of the lithium battery module 1 is detected to be higher than a certain temperature threshold, the heating relay 61 is opened to prevent the lithium battery module 1 from overheating and ensure that the lithium battery module 1 works normally.

[0110] The electric heating module 6, through the coordinated design of the heating relay 61, heating fuse 62, and heating film 22, achieves precise temperature control and safe heating of the lithium battery module 1. On one hand, the heating circuit composed of the sodium battery module 2, heating relay 61, and heating fuse 62 can drive the heating film 11 to work when powered by the sodium battery module 2, solving the problem of the lithium battery module 1 not working properly in low-temperature environments. Simultaneously, the on / off state of the heating relay 61 is controlled by the main control module 7 and the protection board module 22 based on the temperature signal of the lithium battery module 1; it closes to heat at low temperatures and opens to stop at high temperatures, achieving adaptive temperature control, avoiding overheating, and ensuring the stable operation of the lithium battery module 1.

[0111] On the other hand, the heating fuse 62, as a circuit protection element, can melt and cut off the power supply when an overcurrent or short circuit occurs in the heating circuit. Together with the active control of the relay, it forms a dual safety mechanism of active regulation and passive protection, which not only prevents abnormal circuit damage to the heating film or battery module, but also improves the overall safety of the heating system and ensures that the low-temperature heating function is reliable and safe.

[0112] In some embodiments, such as Figure 2 and Figure 3 As shown, the sodium-ion and lithium-ion battery pack also includes a charging connector 86 and a charging relay 33. The charging connector 86 is used to connect to an external power source. The positive terminal of the charging connector 86 is connected to the positive terminal of the heating film 11 in sequence through the charging relay 33, the positive terminal of the input terminal of the first DC-DC module 4, and the positive terminal of the output terminal of the first DC-DC module 4. The negative terminal of the heating film 11 is connected to the negative terminal of the charging connector 86, forming a second heating circuit.

[0113] For example, the lithium battery module 1 is connected to the charging connector 86 via a copper busbar / wire harness to enable the lithium battery module 1 to supply power to high-voltage electrical equipment and to charge the lithium battery module 1 via the charging connector 86.

[0114] When the sodium battery module 2 is low on power, it can be externally heated by connecting the charging connector 86, the charging relay 33, the first DC-DC module 4, and the heating film 11 in the lithium battery module 1, thereby improving the ability of the mixed sodium-ion and lithium-ion battery pack to cope with complex working conditions.

[0115] The design of the second heating circuit provides a redundant heating scheme for battery packs using both sodium-ion and lithium-ion batteries, significantly improving the reliability and adaptability of the low-temperature heating function. On the one hand, when the sodium battery module 2 is insufficient to drive the heating film 11, an external power source can be connected through the charging connector 86. The circuit formed by the charging relay 33 and the first DC-DC module 4 supplies power to the heating film 11, ensuring that the lithium battery module 1 can still receive heating support in low-temperature environments. This avoids the heating function failing due to the malfunction of the sodium battery module 2, thus solving the limitations of a single heating power source.

[0116] On the other hand, the charging connector 86 is reused as the access point for the heating circuit, taking into account charging, power supply, and heating functions. This improves the integration and utilization rate of internal components in the hybrid sodium-ion and lithium-ion battery pack. Simultaneously, the on / off control of the charging relay 33 and the voltage adaptation of the first DC-DC module 4 ensure the safety and stability of the external power supply heating process. Overall, this enhances the hybrid sodium-ion and lithium-ion battery pack's ability to cope with complex operating conditions (such as sodium battery module 2 being depleted and the environment being low), further ensuring the normal operation of lithium battery module 1.

[0117] In some embodiments, such as Figure 2 and Figure 3 As shown, the positive terminal of lithium battery module 1 is connected to the positive terminal of charging connector 86 through charging relay 33, and the negative terminal of lithium battery module 1 is connected to the negative terminal of charging connector 86 through main negative relay 32, forming a charging circuit for a mixed sodium-ion and lithium-ion battery pack (to replenish the energy of lithium battery module 1).

[0118] That is, the charging relay 33 is connected between the positive terminal of the lithium battery module 1 and the charging connector 86, and the main negative relay 32 is connected between the negative terminal of the lithium battery module 1 and the negative terminal of the charging connector 86.

[0119] Through the cooperation of charging relay 33, main negative relay 32 and charging connector 86, a safe and controllable energy replenishment channel is provided for lithium battery module 1, realizing precise control of the charging process. By controlling the on and off of the two relays (charging relay 33 and main negative relay 32), charging can be actively started or stopped, avoiding cell damage caused by continuous charging of lithium battery module 1 in fully charged or faulty states, and ensuring the orderly operation of the charging process. Relays are set in the positive and negative circuits respectively, which can quickly disconnect in case of abnormal conditions such as overvoltage and overcurrent, completely cutting off the charging circuit, preventing the fault from expanding, and isolating the external power supply from the lithium battery module, reducing the risk of leakage and short circuit, and enhancing charging safety. As a standardized interface, charging connector 886 improves the convenience of energy replenishment, facilitates the quick access of external power, ensures that lithium battery module 1 can replenish energy in time, maintain its ability to power external devices or replenish sodium battery module 2, and ensure the continuous operation of the entire sodium-ion and lithium-ion battery pack.

[0120] In some embodiments, such as Figure 2 and Figure 3 As shown, the battery pack for both sodium-ion and lithium-ion batteries also includes a BDU module 3, which includes a main positive relay 31 and / or a main negative relay.

[0121] The first terminal of the main positive relay 31 is connected to the positive terminal of the lithium battery module 1, and the second terminal of the main positive relay 31 is used to connect to the positive terminal of an external load. The first terminal of the main negative relay is connected to the negative terminal of the lithium battery module 1, and the second terminal of the main negative relay is used to connect to the negative terminal of an external load.

[0122] The positive and negative terminals of lithium battery module 1 are connected in series with the main positive relay 31 and the main negative relay 32 in BDU module 3 through copper busbars to realize the on / off control of the charging and discharging circuit of lithium battery module 1.

[0123] For example, the lithium battery module 1 is connected to the BDU module 3 via a copper busbar / wire harness.

[0124] The main control module 7 monitors the voltage, temperature and other information of the individual cells in the lithium battery module 1, and controls the relays in the BDU module 3 to realize the pre-charging, charging and discharging management and thermal management of external electrical equipment.

[0125] BDU module 3, through the coordinated design of main positive relay 31 and main negative relay 32, provides core control and protection functions for the charging and discharging circuit of lithium battery module 1. On one hand, the two relays (main positive relay 31 and main negative relay 32) are connected in series in the positive and negative circuits of lithium battery module 1 and the external load, respectively. They can precisely control the connection and disconnection of the circuit through on / off states, providing an execution platform for the main control module 7 to implement charging and discharging management. For example, during the pre-charging stage, the relays' step-by-step actions prevent large currents from directly impacting the external load, protecting the equipment and the battery; in case of faults (such as over-temperature or over-voltage), they quickly disconnect, completely isolating lithium battery module 1 from the load and preventing the danger from escalating.

[0126] On the other hand, the copper busbar connection method ensures low impedance and stability during high current transmission, reducing connection loss and heat generation. Meanwhile, the main positive relay 31 and the main negative relay 32 serve as the execution terminals for monitoring information from the main control module 7. They can respond to the adjustment of parameters such as temperature and voltage, realize dynamic management and thermal management coordination of the charging and discharging process, and ensure that the lithium battery module 1 supplies power to the external load within a safe range. Overall, this improves the reliability, safety and controllability of the mixed sodium-ion and lithium-ion battery pack when interacting with external devices.

[0127] In some embodiments, such as Figure 2 and Figure 3 As shown, the sodium-ion and lithium-ion battery pack also includes a charging relay 33 and a charging connector 86. The BDU module 3 is connected to the main control module 7. The positive terminal of the lithium battery module 1 is connected to the positive terminal interface of the charging connector 86 through the charging relay 33, and the negative terminal of the lithium battery module 1 is connected to the negative terminal interface of the charging connector 86 through the main negative relay.

[0128] The charging connector 86 is used to connect to an external power source. When both the charging relay 33 and the main negative relay 32 are closed and the charging connector 86 is connected to the external power source, the external power source, the charging / discharging connector 86, the charging relay 33, the main negative relay 32, and the lithium battery module 1 constitute the charging circuit of the sodium-ion and lithium-ion battery pack, which replenishes the lithium battery module 1.

[0129] That is, when both the charging relay 86 and the main negative relay 32 are in the closed state, and the charging connector 86 is connected to the external power source, the lithium battery module 1, the charging relay 33, the charging connector 86, the main negative relay 32 and the external power source form a closed circuit to charge the lithium battery module 1.

[0130] Through the coordination of charging relay 33, main negative relay 32, and charging connector 86, a safe and controllable energy replenishment channel is provided for lithium battery module 1. By controlling the on / off state of the two relays (charging relay 33 and main negative relay 32), charging can be actively started or stopped, adapting to the state of the lithium battery module (such as full charge, disconnection in case of failure), avoiding damage to the battery cells from ineffective charging or overcharging, ensuring the orderly charging process, and making the charging process precise and controllable.

[0131] The charging relay 33 and the main negative relay 32 control the positive and negative circuits respectively. In case of abnormal conditions such as overvoltage, overcurrent, and overtemperature, they can respond to the instructions of the main control module to quickly disconnect, completely cut off the connection between the external power supply and the lithium battery module, prevent the fault from expanding, isolate the high voltage circuit, reduce the risk of leakage, and enhance charging safety.

[0132] As a standardized interface, the charging connector 86 facilitates quick access to external power. Combined with the linkage between the BDU module 3 and the main control module 7, it can dynamically adjust the charging process according to the real-time status (such as voltage and temperature) of the lithium battery module 1, realize intelligent energy replenishment, ensure continuous and stable power supply to the lithium battery module 1, and enhance the convenience of energy replenishment and overall reliability of the mixed sodium-ion and lithium-ion battery pack.

[0133] In some embodiments, such as Figure 2 and Figure 3 As shown, the BDU module 3 also includes a pre-charge relay 34 and a pre-charge resistor 35. The pre-charge relay 34 and the pre-charge resistor 35 are connected in series and then connected in parallel to the two ends of the main positive relay 31.

[0134] A series module consisting of a pre-charge relay 34 and a pre-charge resistor 35 is connected in parallel across the main positive relay 31 to prevent damage to the battery pack itself caused by the large current generated by the load capacitor.

[0135] The design of the pre-charge relay 34 and pre-charge resistor 35 in BDU module 3 solves the problem of high current surge caused by the load capacitor when powering on a mixed sodium-ion and lithium-ion battery pack. Initially, the main positive relay 31 is not closed; instead, the pre-charge relay 34 and main negative relay 32 are closed. Current flows to the external load after being limited by the pre-charge resistor 35. At this time, the load capacitor charges slowly, preventing the surge current generated during the initial short circuit of the capacitor from directly impacting the cells of lithium battery module 1. It also prevents the high current from burning the contacts of the main positive relay 31, protecting the core components of the mixed sodium-ion and lithium-ion battery pack from damage. Once the load capacitor voltage is close to the battery voltage and the surge current risk is eliminated, the main positive relay 31 is closed and the pre-charge relay 34 is opened. Subsequent current is transmitted directly through the low-impedance main positive relay 31. This avoids the power loss caused by the long-term operation of the pre-charge resistor 35 and ensures efficient current transmission during normal power supply, achieving a balance between surge protection and efficient power supply. This significantly improves the safety and reliability of the mixed sodium-ion and lithium-ion battery pack when connected to an external load.

[0136] In some embodiments, such as Figure 2 and Figure 3 As shown, the sodium-ion and lithium-ion battery pack also includes a first positive discharge connector 83, a first negative discharge connector 84, and a second discharge connector 86.

[0137] The first end of the first discharge positive connector 83 is connected to the positive terminal of the lithium battery module 1 through the main positive relay 31, and the second end of the first discharge positive connector 83 is used to connect to the positive terminal of an external electrical device.

[0138] The first end of the first discharge negative connector 84 is connected to the negative terminal of the lithium battery module 1 through the main negative relay and the current transformer 36, and the second end of the first discharge negative connector 84 is used to connect to the negative terminal of external electrical equipment.

[0139] The main positive relay 31 and main negative relay 32 in BDU module 3 are connected to the first discharge positive connector 83 and the first discharge negative connector 84 respectively to supply power to external electrical equipment.

[0140] For example, the lithium battery module 1 is connected to the BDU module 3, the first discharge positive connector 83, the first discharge negative connector 84 and the charging connector 86 via copper busbars / wire harnesses to provide power to the high-voltage electrical equipment and charge the lithium battery module 1.

[0141] The negative terminals of the discharge negative connector 84 and the charging connector 86 are connected together, and the common connection point is connected to the negative terminal of the lithium battery module 1 through the main negative relay 32. The main negative relay 32 can control the on / off state of the charging circuit of the lithium battery module 1, as well as the on / off state of the discharge circuit of the lithium battery module 1.

[0142] The first discharge positive / negative connectors are connected to the lithium battery module 1 through the main positive relay 31 and the main negative relay 32, respectively, clearly establishing a dedicated channel for powering external electrical equipment. The on / off state of the main positive / negative relays can directly control the start and stop of the discharge circuit. In conjunction with the current transformer 36 monitoring the discharge current, it can promptly avoid abnormalities such as overcurrent, ensure the stability of the discharge process, and prevent damage to external equipment or the battery module due to abnormal current.

[0143] The negative terminals of the discharge connector 84 and the charging connector 86 are connected together and share the main negative relay 32, realizing a reuse design that controls the charging and discharging negative circuits with a single relay. This eliminates the need to add a separate negative relay for discharging, which simplifies the internal circuit structure of the battery pack that uses both sodium-ion and lithium-ion batteries, reduces the number of components (reducing cost and installation space), reduces potential failure points, and improves system integration and reliability.

[0144] In addition, this design works in conjunction with the control logic of BDU module 3. The main control module 7 can manage the charging and discharging process in a unified manner through the on / off state of each relay and current monitoring, ensuring that discharging and charging do not interfere with each other. At the same time, it allows lithium battery module 1 to switch smoothly between power supply and energy replenishment modes, taking into account the power supply needs of external devices and its own energy replenishment, further improving the working condition adaptability of the mixed sodium-ion and lithium-ion battery pack.

[0145] In some embodiments, such as Figure 2 and Figure 3 As shown, the battery pack for both sodium-ion and lithium-ion batteries also includes a second discharge connector 85. The positive terminal of the second discharge connector 85 is connected to the positive terminal of the sodium battery module 2, and the negative terminal of the second discharge connector 85 is connected to the negative terminal of the sodium battery module 2.

[0146] For example, the sodium battery module 2 is connected to the protection board module 22 and the second discharge connector 85 via a copper busbar / wiring harness to supply power to the electrical equipment. The electrical equipment mentioned here includes external electrical equipment and electrical components inside the sodium-ion and lithium-ion battery pack.

[0147] The second discharge connector 85 connects to the positive and negative terminals of the sodium battery module 2, efficiently supplying power to external electrical equipment and internal components (such as the main control module and heating film) of the mixed sodium-ion and lithium-ion battery pack, without relying on the lithium battery module 1's circuit, thus enhancing the independence and flexibility of the power supply system. Even if the lithium battery module 1 fails or is not in operation, the sodium battery module 2 can still ensure the power supply to critical equipment through this connector, preventing system function interruption. Simultaneously, in conjunction with the protection board module 22 of the sodium battery module 2, the second discharge connector 85 can rely on the protection board module 22's monitoring and protection functions for voltage, current, and temperature during power supply to ensure stable and safe power to internal and external equipment. Furthermore, the copper busbar / wire harness connection method ensures reliable current transmission, reduces connection losses, improves power supply efficiency, and further adapts to the diverse auxiliary power needs of internal and external equipment.

[0148] In some embodiments, such as Figure 2 and Figure 3 As shown, the battery pack for both sodium-ion and lithium-ion batteries also includes a current transformer 36, which is connected in series with the main negative relay and is also connected to the main control module 7. The negative terminal of the charging connector 86 is connected to the negative terminal of the lithium battery module 1 through the current transformer 36 and the main negative relay 32.

[0149] The main control module 7 monitors the charging and discharging current and calculates the state of charge (SOC) in real time through interaction with the current transformer 36.

[0150] The main control module 7 is responsible for the operation status of the entire sodium-ion and lithium-ion battery pack. By receiving information from the slave control module 14, the protection board module 22 and the current transformer 36, it monitors the voltage, temperature and current of each circuit of the lithium battery module 1 and the sodium battery module 2, and calculates the SOC of the lithium battery module 1 in real time to perform charge and discharge management.

[0151] The current transformer 36, connected in series with the main negative relay 32 and the main control module 7, forms the basis for precise monitoring and management of the charging and discharging current of the mixed sodium-ion and lithium-ion battery pack. The current transformer 36, connected in series with the negative terminal of the charging and discharging circuit, can sense the magnitude of the charging and discharging current of the lithium battery module 1 in real time, providing accurate current data to the main control module 7. This provides a basis for real-time calculation of the lithium battery module's SOC (State of Charge), ensuring the accuracy of SOC assessment and providing a reliable reference for subsequent charging reminders and energy replenishment control.

[0152] After the current data is transmitted to the main control module 7, it works in conjunction with the voltage and temperature information collected by the slave control module 14 and the monitoring data from the protection board module 22 to form a comprehensive perception of the operating status of the lithium battery module 1 and the sodium battery module 2. This helps the main control module 7 to accurately determine whether the charging and discharging is within a safe range (such as whether there is overcurrent), thereby dynamically regulating the charging and discharging management (such as controlling the on and off of relays) to avoid overcurrent damage to the battery cells or external equipment.

[0153] This closed-loop design of "current monitoring-data feedback-intelligent control" improves the transparency and controllability of the entire sodium-ion and lithium-ion battery pack's operating status, allowing the main control module 7 to more scientifically coordinate the charging and discharging process, further ensuring the safety and lifespan of the sodium-ion and lithium-ion battery pack.

[0154] In some embodiments, such as Figure 2 and Figure 3 As shown, the battery pack that combines sodium-ion and lithium-ion batteries also includes a liquid cooling component 81, which is disposed on at least one side of the lithium battery module 1 and the second battery module 2.

[0155] The liquid cooling component 81 can be integrated into the lower housing 8. By setting the liquid cooling component 81, the lithium battery module 1 and the sodium battery module 2 can be cooled, so that the entire sodium-ion and lithium-ion battery pack system can operate at the optimal temperature.

[0156] The liquid cooling component 81 is designed to provide an efficient means of heat dissipation and temperature balance for battery packs that use both sodium-ion and lithium-ion batteries. Through direct or indirect contact with the lithium battery module 1 and the sodium battery module 2, the liquid cooling component 81 can quickly absorb the heat generated by both during charging and discharging, avoiding performance degradation of the cells (such as capacity reduction and shortened cycle life) or the risk of thermal runaway due to excessively high local temperatures. This ensures that the lithium battery module 1 and the sodium battery module 2 always operate within their optimal temperature range, improving energy conversion efficiency and operational stability.

[0157] The liquid cooling component 81 is integrated into the lower housing 8. This design enables uniform cooling of the lithium battery module 1 and sodium battery module 2 through a structured layout, avoiding overheating of a single battery module or uneven temperature distribution, and ensuring the temperature consistency of the entire system.

[0158] In addition, the liquid cooling component 81 and the heating film 11 form a two-way temperature control system of "low temperature heating - high temperature cooling". At low temperatures, the temperature is increased by the heating film 11, and at high temperatures, the temperature is dissipated by the liquid cooling component 81. This allows the hybrid sodium-ion and lithium-ion battery pack to maintain the optimal operating temperature under different ambient temperatures (such as high temperatures in summer and low temperatures in winter) or operating conditions (such as high power discharge), further extending the life of the cells, reducing the probability of failure due to abnormal temperature, and improving the overall reliability of the hybrid sodium-ion and lithium-ion battery pack.

[0159] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0160] The above description is merely a specific embodiment of this disclosure, enabling those skilled in the art to understand or implement it. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this disclosure. Therefore, this disclosure is not to be limited to the embodiments described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A sodium-ion and lithium-ion battery hybrid battery pack, characterized by, include: A lithium battery module includes: a lithium-ion cell assembly and a heating film; the heating film is disposed on at least one side of the lithium-ion cell assembly; The sodium battery module includes: a sodium-ion battery cell assembly connected to the heating film; The main control module is connected to the lithium battery module and the sodium battery module; A first DC-DC module, the input terminal of which is electrically connected to the lithium battery module, and the output terminal of which is electrically connected to the sodium battery module; The second DC-DC module has its input terminal connected to the sodium-ion battery cell assembly and its output terminal connected to the main control module. The lithium battery module is used to transmit electrical energy to the sodium battery module through the first DC-DC module; The sodium battery module is used to control the sodium-ion battery cell assembly to transmit electrical energy to the main control module through the second DC-DC module in response to an activation signal from an external device.

2. The sodium-ion and lithium-ion battery hybrid battery pack of claim 1, wherein, The sodium battery module also includes a protection board module, which is connected in series with the sodium-ion battery cell assembly and connected to the main control module. The protection board module is used to collect at least one of the temperature information, voltage information and current information of each sodium-ion battery cell in the sodium-ion battery cell assembly, and transmit the collected information to the main control module. The sodium-ion and lithium-ion hybrid battery pack also includes a communication connector, which is connected to the main control module and the protection board module; the communication connector is also used to connect to external electrical equipment. The protection board module is used to switch to the working state in response to the activation signal from the external device when the communication connector is connected to the external power device, and to control the second DC-DC module to output power to the main control module.

3. The sodium-ion and lithium-ion battery hybrid battery pack of claim 2, wherein, The protection board module includes a switching element and a first fuse; The first end of the switching element is connected to the sodium battery module, and the other end of the switching element is used to connect to an external load; the switching element is used to close when the voltage, temperature and current of the sodium-ion battery cell are all less than a set threshold, and to open when at least one of the voltage, temperature and current of the sodium-ion battery cell is greater than or equal to the set threshold. The first end of the first fuse is connected to the sodium battery module, and the other end of the first fuse is used to connect to an external load; the first fuse is used to blow when the sodium battery module experiences a short circuit or continuous overcurrent.

4. The sodium-ion and lithium-ion battery hybrid battery pack of claim 1, wherein, The lithium battery module includes at least two lithium-ion cell assemblies connected in series and a manual maintenance switch, wherein the manual maintenance switch has a built-in second fuse.

5. The sodium-ion and lithium-ion battery pack according to claim 1, characterized in that, The lithium battery module also includes: The slave control module is connected to the master control module; the slave control module is used to collect at least one of the temperature information and voltage information of each lithium-ion cell in the lithium-ion cell assembly, and transmit the collected information to the master control module.

6. The sodium-ion and lithium-ion battery hybrid battery pack of claim 1, wherein, The sodium-ion and lithium-ion battery pack also includes an electric heating module, a charging connector and a charging relay, wherein the charging connector is used to connect to an external power source. The electric heating module includes a heating relay and a heating fuse. The heating relay and the heating fuse are connected in series between the negative electrode of the sodium battery module and the negative electrode of the heating film. The positive electrode of the heating film is connected to the positive electrode of the sodium battery module to form a first heating circuit. The positive terminal of the charging connector is connected to the positive terminal of the heating film in sequence through the charging relay, the positive terminal of the input terminal of the first DC-DC module, and the positive terminal of the output terminal of the first DC-DC module. The negative terminal of the heating film is connected to the negative terminal of the charging connector to form a second heating circuit.

7. The sodium-ion and lithium-ion battery hybrid battery pack of claim 1, wherein, The sodium-ion and lithium-ion battery pack further includes a BDU module, a charging relay, and a charging connector. The BDU module is connected to the main control module. The BDU module includes a main positive relay and / or a main negative relay. The first terminal of the main positive relay is connected to the positive terminal of the lithium battery module, and the second terminal of the main positive relay is used to connect to the positive terminal of an external load. The first terminal of the main negative relay is connected to the negative terminal of the lithium battery module, and the second terminal of the main negative relay is used to connect to the negative terminal of the external load. The positive terminal of the lithium battery module is connected to the positive interface of the charging connector via the charging relay, and the negative terminal of the lithium battery module is connected to the negative interface of the charging connector via the main negative relay.

8. The sodium-ion and lithium-ion battery hybrid battery pack of claim 7, wherein, The BDU module also includes a pre-charge relay and a pre-charge resistor, wherein the pre-charge relay and the pre-charge resistor are connected in series and then in parallel to the two ends of the main positive relay.

9. The sodium-ion and lithium-ion battery hybrid battery pack of claim 7, wherein, The sodium-ion and lithium-ion hybrid battery pack also includes: The first discharge positive connector has a first end connected to the positive terminal of the lithium battery module via the main positive relay, and a second end connected to the positive terminal of an external electrical device. The first discharge negative connector has a first end connected to the negative terminal of the lithium battery module via the main negative relay, and a second end connected to the negative terminal of the external electrical device. The second discharge connector has its positive terminal connected to the positive terminal of the sodium battery module and its negative terminal connected to the negative terminal of the sodium battery module.

10. The sodium-ion and lithium-ion battery hybrid battery pack of claim 7, wherein, The sodium-ion and lithium-ion hybrid battery pack also includes: A current transformer is connected in series with the main negative relay and is also connected to the main control module; The negative terminal of the charging connector is connected to the negative terminal of the lithium battery module through the current transformer and the main negative relay.

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