Battery device, energy storage device, energy storage system and charging network

Abstract

The invention provides a battery device, an energy storage device, an energy storage system and a charging network, and relates to the technical field of batteries, the battery device comprises at least one battery monomer, and a magnetic variation fluid electrolyte is arranged in the battery monomer; the magnetic field generation device is connected with the at least one battery monomer to form an electric loop, the electric loop can be switched between a power-on state and a power-off state based on the temperature of the at least one battery monomer, and when the electric loop is in the power-on state, the magnetic field generation device can generate a magnetic field and act on the magnetic variation fluid electrolyte of the at least one battery monomer. According to the scheme, when the temperature of the single battery is abnormally increased due to overcharge, short circuit and other abuse conditions, the magnetic field generating device generates a magnetic field, the migration rate of lithium ions on an electrode and electrolyte interface is limited, and the battery polarization is improved, so that the charging cut-off voltage of the single battery is reached in advance, and overcharge of the single battery is prevented from continuing; side reactions such as electrolyte decomposition and lithium precipitation are avoided, and finally thermal runaway and fire explosion are prevented.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a battery device, an energy storage device, an energy storage system and a charging network. BACKGROUND

[0002] When a battery cell is overcharged, lithium ions in the positive electrode are excessively stripped out, causing the positive electrode structure to collapse. The unstable structure is in a strong oxidizing state, which causes strong oxidation of the electrolyte and the separator. At the same time, lithium ions stripped out from the positive electrode are deposited on the surface of the negative electrode in large quantities to form lithium dendrites. The strong reducing state of lithium also reacts with the electrolyte. The strong oxidation-reduction reaction inside the battery releases a large amount of heat, plus the joule heat generated by the battery during charging, causing the temperature of the battery cell to rise sharply, triggering a series of reactions such as decomposition of the SEI film (Solid Electrolyte Interphase, SEI film for short), melting of the separator to cause internal short circuit, and decomposition of the electrolyte, thereby causing thermal failure of the battery cell. Therefore, if the deep overcharge of the battery cell can be prevented, the above reactions can be greatly reduced.

[0003] In related solutions, battery overcharge protection technology mainly relies on the chemical protection mechanism inside the battery (such as overcharge decomposition of positive and negative electrode materials). However, these methods have the problem of insufficient reliability: the chemical protection mechanism inside the battery may fail under certain extreme conditions (such as high temperature or rapid charging), and cannot effectively prevent overcharging.

[0004] Therefore, how to propose a better reliable overcharge prevention technology has become a technical problem to be solved. SUMMARY

[0005] Therefore, the present application provides a battery device with better reliability and capable of preventing overcharging.

[0006] To this end, a first aspect of the present application provides a battery device.

[0007] A second aspect of the present application provides an energy storage device.

[0008] A third aspect of the present application provides an energy storage system.

[0009] A fourth aspect of the present application provides a charging network.

[0010] Therefore, the first aspect of the present application provides a battery device, comprising: at least one battery cell, a magnetic variable fluid electrolyte is arranged in the battery cell; a magnetic field generating device connected with the at least one battery cell to form an electric circuit, the electric circuit can switch between an energized state and a de-energized state based on the temperature of the at least one battery cell, and the magnetic field generating device can generate a magnetic field and act on the magnetic variable fluid electrolyte of the at least one battery cell when the electric circuit is in the energized state.

[0011] According to the battery device provided by the present application, the magnetic field generating device is directly connected with the battery cell to form a temperature responsive electric circuit. When the battery cell is in a normal temperature range (for example, -30℃ to 80℃), the temperature of the battery cell is normal, the electric circuit is de-energized, the magnetic field generating device does not generate a magnetic field, the magnetic variable fluid electrolyte is in a first state (normal state) of natural flow, the magnetic variable fluid electrolyte maintains a low viscosity flow state, lithium ions can freely migrate, and the battery normally charges and discharges. When the temperature of the battery abnormally rises (for example, >80℃) due to misuse such as overcharging and short circuit, the electric circuit is energized, the magnetic field generating device generates a magnetic field, the magnetic particles in the magnetic variable fluid electrolyte are orderly arranged along the direction of the magnetic field to form a chain structure, the viscosity of the electrolyte sharply increases or even solidifies, the migration rate of lithium ions at the interface between the electrode and the electrolyte is limited, the polarization of the battery (including concentration difference polarization and electrochemical polarization) is significantly improved, and thus the charging cut-off voltage of the battery cell is reached in advance, the overcharging of the battery cell is prevented from continuing, the side reactions such as electrolyte decomposition and lithium precipitation are avoided, and finally the thermal runaway and fire explosion are prevented.

[0012] In the present application, through the linkage mechanism of "temperature sensing-magnetic field regulation-electrolyte rheology", the active protection of battery overcharging is realized, without the need for additional complex protection circuit, the structure is simple and the integration is high; under normal working conditions, the battery performance is not affected, and the protection is triggered only in abnormal conditions, and the safety and electrochemical performance are considered; the state switching of the magnetic variable fluid electrolyte is reversible (the magnetic field disappears and the electrolyte flows again after the temperature returns to normal), which ensures the reversible cycle utilization of the battery.

[0013] In any of the above technical solutions, the battery device further comprises a temperature control device for detecting the temperature of the at least one battery cell and controlling whether the magnetic field generating device generates a magnetic field according to the detected temperature of the at least one battery cell.

[0014] In the above technical solutions, the temperature control device can realize accurate real-time monitoring of the temperature of the battery cell, and provide clear triggering basis for the magnetic field generating device, so that the magnetic field generating device can be triggered in time based on the temperature of the battery cell, and the overcharging of the battery device is prevented.

[0015] In any of the above technical solutions, optionally, the magnetic field generating device comprises: a coil connected with the at least one battery monomer into an electric circuit, the electric circuit being capable of switching between an energized state and a de-energized state based on the temperature of the at least one battery monomer, the coil being capable of generating a magnetic field and acting on the magnetic variable fluid electrolyte of the at least one battery monomer when the electric circuit is in the energized state.

[0016] In the technical solutions, a temperature-responsive electric circuit is formed by directly connecting the coil with the battery monomer, the coil is energized to generate a magnetic field only when the temperature is abnormal, there is no energy consumption under normal working conditions, and interference to the charging and discharging performance of the battery is avoided; the magnetic field directly acts on the magnetic variable fluid electrolyte, overcharge protection is realized through rheological property regulation, the response speed is fast (on the order of milliseconds), and the state switching is reversible (the magnetic field disappears and the electrolyte flows again after the temperature recovers), thereby ensuring the reversible cyclic utilization of the battery and effectively solving the problems of non-recovery and large capacity loss of traditional passive protection schemes (such as a fuse), and the safety and economy of the battery system are significantly improved.

[0017] In any of the above technical solutions, optionally, the magnetic field generating device further comprises: a temperature control switch connected in series in the electric circuit and capable of switching the on-off state of the electric circuit based on the temperature of the at least one battery monomer, so that the electric circuit is in the energized state or the de-energized state.

[0018] In the technical solution, the temperature control switch is directly connected in series in the electric circuit, the temperature control switch is triggered accurately based on the temperature, the magnetic field regulation is triggered only when the temperature is abnormal, there is no energy consumption under normal working conditions, and the battery performance is not affected, and safety and efficiency are considered.

[0019] In any of the above technical solutions, optionally, the coil is a temperature-sensitive coil, the temperature-sensitive coil is capable of switching the electric circuit between the energized state and the de-energized state based on the temperature of the at least one battery monomer.

[0020] In the technical solution, the temperature-sensitive coil itself integrates temperature sensing and magnetic field generation functions, without the need for an additional independent control module (such as a temperature control switch or a battery management system (BMS)), thereby simplifying the structure of the battery device and reducing the cost of the battery device.

[0021] In any of the above technical solutions, optionally, the coil is one or more. The number of coils can be reasonably set based on actual needs, multiple coils can form one electric circuit, or multiple electric circuits.

[0022] In any of the above technical solutions, optionally, the coil is connected with the positive electrode and the negative electrode of one of the battery monomers into an electric circuit.

[0023] In the technical solution, the coil is connected to form an electric circuit with the positive and negative poles of the battery monomer. Then, the combination of the coil and the electromagnetic monomer is installed as a component in the battery module or the battery pack.

[0024] In any of the above technical solutions, the number of battery monomers is multiple, and the multiple battery monomers are connected in series and / or in parallel to form at least one battery group. The coil is connected to the total positive pole and the total negative pole of the battery group to form an electric circuit.

[0025] In the technical solution, in order to simplify the wiring of the coil, multiple battery monomers can share one coil. For example, one coil can be used in one battery module, or only one large coil can be used in one battery pack.

[0026] This arrangement can simplify the layout of the battery device and optimize the overall structure of the battery device.

[0027] In any of the above technical solutions, the battery device further comprises a shell, at least one battery monomer is installed in the shell, at least part of the coil is installed outside the shell, at least part of the coil is in contact with the outer wall of the shell, or the coil is installed in the shell, and at least part of the coil is in contact with the inner wall of the shell.

[0028] In this application, the shell serves as a mechanical barrier to protect the battery monomer, and the contact between the coil and the shell can strengthen heat conduction (such as a metal shell quickly spreads the heat generated by the coil or the battery), improve the heat dissipation efficiency; on the other hand, the coil is arranged close to the shell, which shortens the magnetic field transmission path (especially when the shell is a magnetic conductive material), reduces the magnetic circuit loss, and enhances the action strength of the magnetic field on the electrolyte.

[0029] In any of the above technical solutions, the battery device is a battery pack, a battery module or a battery box.

[0030] In the technical solutions, the battery device can be a battery pack, and a total magnetic field generating device can be arranged in the battery pack to generate a magnetic field to polarize the battery monomers in advance, reach the cut-off voltage in advance, and avoid overcharging. The battery device can be a battery module, and a total magnetic field generating device can be designed in the battery module to avoid overcharging of the battery module.

[0031] Of course, the battery device can also be a battery box, so that the energy storage device can realize overcharge protection when charging.

[0032] In any of the above technical solutions, at least part of the coil is arranged at least one of the bottom, side and top of the at least one battery monomer.

[0033] In the technical solutions, the coil can be arranged at a position required by actual needs, for example, at the bottom, side or top of the battery monomer.

[0034] The second aspect of the present application provides an energy storage device, comprising at least one battery device according to any one of the first aspect.

[0035] The energy storage device provided by the present application has all the beneficial effects of the battery device according to any one of the first aspect, which will not be repeated here.

[0036] The third aspect of the present application provides an energy storage system, comprising an energy conversion system and an energy storage device according to any one of the second aspect, wherein the energy conversion system is connected to the energy storage device to convert the current input into or output from the energy storage device.

[0037] The energy storage system provided by the present application has all the beneficial effects of the energy storage device according to any one of the second aspect, which will not be repeated here.

[0038] The fourth aspect of the present application provides a charging network, comprising a charging pile; and an energy storage device according to any one of the second aspect or an energy storage system according to any one of the third aspect, wherein the energy storage device is used to provide electric energy for the charging pile.

[0039] The charging network provided by the present application has all the beneficial effects of the energy storage device according to any one of the second aspect or the energy storage system according to any one of the third aspect, which will not be repeated here.

[0040] Additional aspects and advantages of the present application will become apparent from the following description with reference to the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0041] The above and / or additional aspects and advantages of the present application will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings, in which:

[0042] Figure 1 One of the structural schematic diagrams of the battery device in some embodiments of the present application;

[0043] Figure 2 One of the structural schematic diagrams of the battery device in some embodiments of the present application;

[0044] Figure 3 One of the structural schematic diagrams of the battery device in some embodiments of the present application;

[0045] Figure 4 A structural schematic diagram of a battery device in some embodiments of the present application;

[0046] Figure 5 A structural schematic diagram of a battery device in some embodiments of the present application;

[0047] Figure 6 A structural schematic diagram of a battery device in some embodiments of the present application;

[0048] Figure 7 A structural schematic diagram of a battery device in some embodiments of the present application;

[0049] Figure 8 A structural schematic diagram of a battery device in some embodiments of the present application;

[0050] Figure 9 A structural schematic diagram of a battery device in some embodiments of the present application;

[0051] Figure 10 A structural schematic diagram of a battery device in some embodiments of the present application;

[0052] Figure 11 A structural schematic diagram of a battery device in some embodiments of the present application;

[0053] Figure 12 A performance comparison schematic diagram of a battery device in the present application and a battery device in related schemes;

[0054] Figure 13 A state of a magnetic variable fluid electrolyte in some embodiments of the present application before a magnetic field is applied;

[0055] Figure 14 A state of a magnetic variable fluid electrolyte in some embodiments of the present application after a magnetic field is applied;

[0056] Figure 15 A structural schematic diagram of a battery device in some embodiments of the present application;

[0057] Figure 16 A structural schematic diagram of an energy storage system in some embodiments of the present application;

[0058] Figure 17 A structural schematic diagram of a charging network in some embodiments of the present application.

[0059] In the drawings:

[0060] 100 battery device, 1 battery cell, 12 magnetic particles, 14 positive electrode, 16 negative electrode, 2 magnetic field generating device, 22 coil, 24 temperature control switch, 4 temperature sensitive coil, 5 total positive electrode, 6 total negative electrode, 7 shell, 8 temperature control device, 200 energy storage device, 300 energy conversion system, 400 power generation equipment, 500 charging pile, 510 connector. DETAILED DESCRIPTION

[0061] In order to enable the above-mentioned purposes, features and advantages of the present application to be more clearly understood, the present application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0062] In the following description, many specific details are set forth in order to provide a thorough understanding of the present application, but the present application can also be implemented in other ways different from those described herein, therefore, the scope of protection of the present application is not limited by the specific embodiments disclosed below.

[0063] When the battery cell is overcharged, lithium ions in the positive electrode are excessively removed, causing the positive electrode structure to collapse, and the unstable structure is in a strong oxidation state, which has a strong oxidizing effect on the electrolyte and the separator. At the same time, the lithium ions removed from the positive electrode are deposited on the surface of the negative electrode to form lithium dendrites, and the strong reducing state of lithium also reacts with the electrolyte. In this way, the strong oxidation-reduction reaction inside the battery releases a large amount of heat, plus the joule heat generated by the battery itself during charging, causing the battery cell temperature to rise sharply, triggering a series of reactions such as SEI film decomposition, separator melting, internal short circuit and electrolyte decomposition, thereby causing the battery cell to fail. Therefore, if the battery cell can be prevented from being deeply overcharged, the occurrence of the above reactions can be greatly reduced.

[0064] In the related scheme, the battery overcharge protection technology mainly relies on the chemical protection mechanism inside the battery (such as the overcharge decomposition of the positive and negative electrode materials). However, these methods have the problem of insufficient reliability: the chemical protection mechanism inside the battery may fail under some extreme conditions (such as high temperature or rapid charging), and cannot effectively prevent overcharging.

[0065] Therefore, how to construct a battery device which can quickly raise the voltage to the cutoff voltage (protection voltage) when the battery is overcharged, so as to reduce the overcharge capacity (such as from 117% SOC (State of Charge) to 107% SOC), thereby avoiding the risk of thermal runaway, even fire and explosion of the battery, is a problem to be solved by the present application. Figure 12

[0066] To solve the above technical problems, such as Figures 1 to 17 ​As shown, the embodiment provides a battery device 100, which includes a battery cell 1, a magnetic variable fluid electrolyte is arranged inside the battery cell 1, and a magnetic field generating device 2 such as a coil 22 is arranged outside the battery cell 1. The magnetic field generating device 2 such as the coil 22 can be distributed in a battery pack, a battery module or a battery box and connected to the total positive and total negative of the battery pack, the battery module or the battery box. In a normal use state, the magnetic field generating device 2 such as the coil 22 is not powered. Once overcharging occurs in the battery, the temperature inside the battery pack, the battery module or the battery box rises sharply, the magnetic field generating device 2 such as the coil 22 generates current, the coil 22 generates a magnetic field, the electrolyte reduces fluidity or even solidifies in a microsecond, the battery polarization is improved, the cut-off voltage is reached in advance to reduce the overcharge capacity, and the thermal runaway or even fire and explosion is prevented.

[0067] By arranging the magnetic field generating device 2 such as the coil 22, overcharging of the battery can be prevented. The magnetic field control method has high safety and little effect on the performance of the battery, and is very beneficial to popularization and implementation.

[0068] The battery device 100 in the embodiment of the application is specifically a power battery. The battery device 100 can be specifically used in user equipment such as a vehicle or energy storage equipment. The battery device 100 can be specifically a battery pack, a battery module or a battery box.

[0069] The battery device (Battery Apparatus) 100 mentioned in the embodiment of the application can include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly (Battery Cell Assembly) can include a plurality of battery cells connected in series, parallel or mixed connection through a busbar.

[0070] In some embodiments, the battery cell assembly (Battery Cell Assembly) is usually formed by arranging a plurality of battery cells.

[0071] As an example, the battery cell assembly can be a battery module (Battery Module) formed by arranging and fixing a plurality of battery cells into an independent module. As an example, the battery module can be formed by binding a plurality of battery cells with a cable tie.

[0072] In some embodiments, the battery device 100 can be a battery pack (battery Pack), which includes a box body and one or more battery cell assemblies accommodated in the box body.

[0073] As an example, the battery cell assembly can be a battery module, which can be accommodated in the box body by fixing the battery module in the box body.

[0074] As an example, the battery cell assembly can also be accommodated in the box by directly fixing a plurality of battery cells to the box.

[0075] As an example, the box can include a first box and a second box. The first box and the second box are fastened so that an enclosed space is formed inside the box to accommodate the battery cell assembly. The enclosed here means covered or closed, which can be sealed or unsealed. The first box can be a top cover or a bottom plate.

[0076] As an example, the box can include a top cover, a frame and a bottom plate. The top cover and the bottom plate are connected with the frame respectively, so that an enclosed space is formed inside the box to accommodate the battery cell assembly.

[0077] In some embodiments, the box can be part of the chassis structure of the vehicle. For example, part of the box can be at least part of the floor of the vehicle, or part of the box can be at least part of the cross beam and the longitudinal beam of the vehicle.

[0078] The technical solutions described in the embodiments of the present application are applicable to various electric devices using battery cells, such as mobile phones, portable devices, notebook computers, electric vehicles, electric toys, electric tools, vehicles, ships and spacecraft, etc., for example, spacecraft including airplanes, rockets, space shuttles and spaceships, etc.

[0079] The battery device 100, the energy storage device 200, the energy storage system and the charging network in the embodiments will be described below in conjunction with Figures 1 to 17

[0080] As shown in Figures 1 to 10 The first aspect of the present application proposes a battery device 100, comprising at least one battery cell 1 and a magnetic field generating device 2, wherein the battery cell 1 is used as an energy storage core unit, and the inside of the battery cell 1 is filled with a magnetic variable fluid electrolyte; the magnetic field generating device 2 can generate a magnetic field according to the temperature change of the battery cell 1. Specifically, the magnetic field generating device 2 is connected with the at least one battery cell 1 to form an electric circuit, the electric circuit can switch between an energized state and a de-energized state based on the temperature of the at least one battery cell 1, and the magnetic field generating device 2 can generate a magnetic field when the electric circuit is in the energized state and act on the magnetic variable fluid electrolyte of the at least one battery cell 1.

[0081] ​In this structure, the magnetic field generating device 2 can generate a magnetic field when the temperature of the battery cell 1 exceeds its normal operating temperature range, such as -30℃ to 80℃. This magnetic field acts on the magnetorheological fluid electrolyte, interacting with the magnetorheological fluid and changing its distribution in the electrolyte. This causes the magnetorheological fluid electrolyte to switch from a first state with high fluidity to a second state with low fluidity (i.e., the fluidity of the magnetorheological fluid electrolyte in the first state is higher than that in the second state, and the viscosity of the magnetorheological fluid electrolyte in the first state is lower than that in the second state). The specific working principle is as follows: When battery cell 1 is within the normal temperature range (e.g., -30℃ to 80℃), the temperature of battery cell 1 is normal, the magnetic field generating device 2 does not generate a magnetic field, and the magnetic variable fluid electrolyte is in the first state of natural flow (normal state). The magnetic variable fluid electrolyte maintains a low viscosity flow state, lithium ions can migrate freely, and the battery can charge and discharge normally. When the battery temperature rises abnormally due to abuse such as overcharging or short circuit (e.g., >80℃), the magnetic field generating device 2 generates a magnetic field, which causes the magnetic particles in the magnetic variable fluid electrolyte to arrange themselves in an orderly manner along the direction of the magnetic field, forming a chain structure. The viscosity of the electrolyte increases sharply or even solidifies, which limits the migration rate of lithium ions at the electrode and electrolyte interface, significantly improves battery polarization (including concentration polarization and electrochemical polarization), thereby reaching the charging cutoff voltage of battery cell 1 in advance, preventing battery cell 1 from continuing to be overcharged, avoiding side reactions such as electrolyte decomposition and lithium plating, and ultimately preventing thermal runaway and fire and explosion.

[0082] The magnetic field generating device 2 can be specifically a device capable of generating a magnetic field by passing an electric current through it, such as a coil 22 or an electromagnet. The magnetorheological fluid electrolyte is an electrolyte containing magnetic particles and exhibits a low-viscosity flow dynamic under normal conditions.

[0083] In this application, an active protection against battery overcharging is achieved through a linkage mechanism of "temperature sensing - magnetic field regulation - electrolyte rheology". This eliminates the need for additional complex protection circuits, resulting in a simple structure and high integration. Under normal operating conditions, it does not affect battery performance, and only triggers protection in abnormal situations, thus balancing safety and electrochemical performance. The state switching of the magnetorheological fluid electrolyte is reversible (the magnetic field disappears and the electrolyte resumes flow after the temperature recovers), ensuring the reversible recycling of the battery.

[0084] In any of the above embodiments, optionally, as Figure 15 As shown, the battery device 100 further includes a temperature control device 8, which detects the temperature of at least one battery cell 1 and controls whether the magnetic field generating device 2 generates a magnetic field based on the detected temperature of at least one battery cell 1.

[0085] In the embodiments, the battery device 100 further comprises a temperature control device 8. The core function of the temperature control device 8 is to collect the temperature data of at least one battery cell 1 in real time, convert the temperature signal into a control instruction (such as an electrical signal or a digital signal), and then control the working state of the magnetic field generating device 2, that is, decide whether to trigger the magnetic field generating device 2 to generate a magnetic field according to whether the detected temperature reaches a preset threshold. The working principle is as follows: when the temperature of the battery cell 1 is in a safe range (such as -30°C~80°C), the temperature control device 8 outputs a "no need to start" instruction, the magnetic field generating device 2 does not work or maintains a standby state, the magnetic variable fluid electrolyte keeps flowing, the lithium ions migrate freely, and the battery normally charges and discharges; when the temperature of the battery cell 1 rises to a preset threshold (such as >80°C) due to overcharging, abnormal internal resistance, etc., the temperature control device 8 detects an over-temperature signal and outputs a "start" instruction. After receiving the instruction, the magnetic field generating device 2 immediately generates a magnetic field, which acts on the magnetic variable fluid electrolyte to make it viscosity increase dramatically or even solidify, limits the migration of lithium ions, and enhances the polarization of the battery to prevent overcharging.

[0086] The temperature control device 8 can be a battery management system (BMS). Generally, the temperature of the battery cell 1 can be collected by a CSC (Cell Supervision Circuit, cell monitoring unit).

[0087] With this structure, the temperature control device 8 can accurately and timely monitor the temperature of the battery cell 1, and provide clear triggering basis for the magnetic field generating device 2. In this way, the magnetic field generating device 2 can be triggered in time based on the temperature of the battery cell 1, and it is ensured that the battery device 100 will not be overcharged.

[0088] In any of the above embodiments, optionally, as shown in Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 、 Figure 6 、 Figure 7 and Figure 8 , the magnetic field generating device 2 comprises: a coil 22, which is connected with the at least one battery cell 1 to form an electric circuit, the electric circuit can switch between a power-on state and a power-off state based on the temperature of the at least one battery cell 1, and the electric circuit is connected with the positive electrode and the negative electrode to form an electric circuit, the electric circuit comprises a power-on state and a power-off state, and the electric circuit can switch between the power-on state and the power-off state based on the temperature of the at least one battery cell 1, and the coil 22 can generate a magnetic field when the electric circuit is in the power-on state, and the magnetic field acts on the magnetic variable fluid electrolyte of the at least one battery cell 1.

[0089] In the embodiments, the magnetic field generating device 2 comprises a coil 22 connected with the battery monomer 1, the coil 22 serving as a core component of the magnetic field generating device 2 and being capable of being connected with the battery monomer 1 into an electric circuit and mainly used for generating a magnetic field by electrification. The coil 22 comprises a state of generating a magnetic field by electrification and a state of not generating a magnetic field by de-electrification. The on-off state of the electric circuit is dynamically controlled by the temperature of at least one battery monomer 1, that is, when the temperature of the battery monomer 1 is in a safe range (for example, -30℃ to 80℃), the electric circuit is maintained in a de-electrification state, no current passes through the coil 22, no magnetic field is generated, the magnetic variable fluid electrolyte keeps flowing, and the battery normally charges and discharges; when the temperature of the battery is increased to a preset threshold (for example, >80℃) due to overcharge, short circuit or other abnormalities, the electric circuit is automatically switched to an electrification state, the coil 22 generates a strong magnetic field due to electrification, the magnetic field penetrates the battery shell and acts on the internal magnetic variable fluid electrolyte, the internal magnetic particles of the magnetic variable fluid electrolyte are orderly arranged along the direction of the magnetic field to form a chain structure, the viscosity of the electrolyte is sharply increased or even solidified, the migration rate of lithium ions at the interface between the electrode and the electrolyte is limited, and the polarization of the battery is improved to prevent overcharge.

[0090] In the embodiments, the coil 22 can be a spiral structure of copper enameled wire, and the number of turns and the diameter are designed according to the requirement of the magnetic field strength.

[0091] In the embodiments, the coil 22 is directly connected with the battery monomer 1 to form a temperature responsive electric circuit, the coil 22 is electrified to generate a magnetic field only when the temperature is abnormal, and no energy is consumed under normal working conditions, thereby avoiding the interference with the charging and discharging performance of the battery; the magnetic field directly acts on the magnetic variable fluid electrolyte, overcharge protection is realized by rheological property regulation, the response speed is fast (millisecond level), the state switching is reversible (the magnetic field disappears and the electrolyte flows again after the temperature returns to normal), the reversible cycle utilization of the battery is ensured, the problems of non-recovery and large capacity loss of the traditional passive protection scheme (such as a fuse) are effectively solved, and the safety and economy of the battery system are significantly improved.

[0092] In any of the above embodiments, as shown in Figure 1 、 Figure 2 and Figure 3 , the magnetic field generating device 2 further comprises a temperature control switch 24 connected in series in the electric circuit and capable of switching the on-off state of the electric circuit based on the temperature of at least one battery monomer 1, so that the electric circuit is in an electrification state or a de-electrification state.

[0093] In this embodiment, the magnetic field generating device 2 includes a coil 22 connected into an electrical circuit with the at least one battery cell 1, and a temperature control switch 24 connected in series in the electrical circuit, the temperature control switch 24 serving as a core control element for turning on and off the electrical circuit, and being directly connected in series in the circuit between the coil 22 and the battery cell 1, with the contact state of the temperature control switch 24 being determined by the temperature of the at least one battery cell 1. The working principle is as follows: when the temperature of the battery cell 1 is in a safe range (e.g. -30℃~80℃), the temperature control switch 24 remains in an open state because the action threshold is not reached, the electrical circuit is not powered on, no current passes through the coil 22, no magnetic field is generated, the magnetic variable fluid electrolyte maintains a flow state, lithium ions migrate freely, and the battery is normally charged and discharged; when the temperature of the battery cell 1 rises to a preset threshold (e.g. >80℃) due to overcharging, short circuit or other abnormalities, the temperature control switch 24 is triggered to close the contact due to heat, the electrical circuit is turned on, the coil 22 is powered on to generate a strong magnetic field, the magnetic field penetrates the battery shell to act on the internal magnetic variable fluid electrolyte, the internal magnetic particles of the electrolyte are ordered to form a chain structure along the direction of the magnetic field, the viscosity of the electrolyte increases sharply or even solidifies, the migration rate of lithium ions at the interface between the electrode and the electrolyte is limited, and the polarization of the battery is improved to prevent overcharging.

[0094] The temperature switch can be a bimetallic strip temperature controller, a thermistor linkage switch, or an electronic temperature control module, etc.

[0095] By directly connecting the temperature control switch 24 in the electrical circuit, the temperature control switch 24 is triggered accurately based on the temperature, and only closes and triggers the magnetic field regulation in abnormal conditions, without energy consumption and affecting the performance of the battery in normal conditions, and both safety and efficiency are considered.

[0096] In any of the above embodiments, optionally, as shown in Figure 6 , Figure 7 and Figure 8 , the coil 22 is a temperature-sensitive coil 4, which can switch the electrical circuit between the powered-on state and the powered-off state based on the temperature of the at least one battery cell 1.

[0097] In this embodiment, the coil 22 is a temperature-sensitive coil 4, which is a core component of the magnetic field generating device 2. The resistance value of the temperature-sensitive coil 4 changes regularly with the temperature change of the battery monomer 1. When the temperature of the battery monomer 1 is in a safe range (for example, -30°C to 80°C), the resistance of the temperature-sensitive coil 4 is high (or in a high resistance state), the electric circuit is insufficient to drive the magnetic field generation, and the coil 22 does not generate a magnetic field. The magnetic variable fluid electrolyte maintains a flowing state, lithium ions migrate freely, and the battery normally charges and discharges. When the temperature of the battery rises to a preset threshold (for example, >80°C) due to overcharging, short circuit, or other abnormalities, the resistance of the temperature-sensitive coil 4 drops sharply (or switches to a low resistance state), the electric circuit is turned on and generates sufficient current, and the coil 22 generates a strong magnetic field due to the excitation of the current. The magnetic field penetrates the battery shell and acts on the internal magnetic variable fluid electrolyte, causing the internal magnetic particles to align in the direction of the magnetic field and form a chain structure. The viscosity of the electrolyte increases sharply or even solidifies, limiting the migration rate of lithium ions at the electrode and electrolyte interface, and improving the polarization of the battery to prevent overcharging.

[0098] The temperature-sensitive coil 4 is made of a material with significant temperature-resistance characteristics, such as a negative temperature coefficient thermistor (NTC thermistor) or a positive temperature coefficient thermistor.

[0099] By integrating temperature sensing and magnetic field generation functions into the temperature-sensitive coil 4, there is no need for additional independent control modules (such as temperature control switches 24 or BMS), which simplifies the structure of the battery device 100 and reduces the cost of the battery device 100.

[0100] In any of the above embodiments, the coil 22 can be one or more. The number of coils 22 can be reasonably set based on actual needs. Multiple coils 22 can form one electric circuit or multiple electric circuits.

[0101] In any of the above embodiments, the coil 22 can be one or more. The number of coils 22 can be reasonably set based on actual needs. Multiple coils 22 can form one electric circuit or multiple electric circuits. Figures 3 to 8 As shown in

[0102] In this embodiment, the coil 22 is connected to the positive and negative electrodes of the battery monomer 1 to form an electric circuit. After that, the combination of the coil 22 and the electromagnetic monomer can be installed as a component in the battery module or the battery pack.

[0103] In any of the above embodiments, the coil 22 can be one or more. The number of coils 22 can be reasonably set based on actual needs. Multiple coils 22 can form one electric circuit or multiple electric circuits. Figure 1 and Figure 2 As shown in

[0104] In this embodiment, to simplify the wiring of the coil 22, multiple battery cells 1 can share one coil 22. For example, one coil 22 can be used in a battery module, or only one large coil 22 can be used in a battery pack.

[0105] This setup simplifies the layout of the battery device 100 and optimizes its overall structure.

[0106] In any of the above embodiments, optionally, as Figures 1 to 10 As shown, the battery device 100 further includes: a housing 7, at least one battery cell 1 installed inside the housing 7, at least a portion of a coil 22 installed outside the housing 7, at least a portion of the coil 22 contacting the outer wall of the housing 7, or the coil 22 installed inside the housing 7, at least a portion of the coil 22 contacting the inner wall of the housing 7.

[0107] In this embodiment, the battery device 100 includes a housing 7 (made of aluminum alloy, engineering plastic, or carbon fiber composite material, providing mechanical protection and heat dissipation) that houses the battery cell 1. The coil 22 is arranged in two ways: first, the coil 22 is partially or entirely mounted outside the housing 7, and at least partially in direct contact with the outer wall of the housing 7 (e.g., attached to the side wall or bottom of the housing 7); second, the coil 22 is completely mounted inside the housing 7, and at least partially in contact with the inner wall of the housing 7 (e.g., embedded in a groove in the inner wall of the housing 7 or fixed with thermally conductive adhesive). The working principle is as follows: When the temperature of the battery cell 1 is within a safe range (e.g., -30℃ to 80℃), the coil 22 maintains a high resistance state due to its temperature-sensitive characteristics. The electrical circuit is not energized and no magnetic field is generated. The magnetically variable fluid electrolyte maintains its flow state, and the battery is charged and discharged normally. When the temperature rises abnormally (e.g., >80℃), the resistance of the coil 22 drops sharply, the electrical circuit is turned on and current is generated, and the coil 22 generates a strong magnetic field. If the coil 22 is arranged outside the casing 7, the magnetic field can penetrate into the interior through the electromagnetic coupling of the casing 7 (e.g., metal material), or conduct heat to the casing 7 through contact with the outer wall to assist in heat dissipation. If the coil 22 is arranged inside the casing 7, the magnetic field directly acts on the adjacent battery cell 1, reducing magnetic loss and improving efficiency. The magnetic field ultimately acts on the magnetically variable fluid electrolyte, causing its magnetic particles to arrange in an orderly manner to form a chain structure. The viscosity of the electrolyte increases dramatically or even solidifies, limiting lithium ion migration to prevent overcharging.

[0108] In this application, the outer casing 7 acts as a mechanical barrier to protect the battery cell 1. At the same time, the contact between the coil 22 and the outer casing 7 can enhance heat conduction (such as the metal outer casing 7 heating up the coil 22 or rapidly dissipating the battery heat), thereby improving heat dissipation efficiency. On the other hand, the coil 22 is arranged close to the outer casing 7, which shortens the magnetic field transmission path (especially when the outer casing 7 is made of a magnetically conductive material), reduces magnetic circuit loss, and enhances the strength of the magnetic field's effect on the electrolyte.

[0109] In any of the above embodiments, the battery device 100 can be a battery pack, a battery module or a battery box.

[0110] In the embodiments, the battery device 100 can be a battery pack, in which a total magnetic field generating device 2 can be arranged to generate a magnetic field to pre-polarize the battery cells 1 and to pre-achieve the cut-off voltage to avoid overcharging. The battery device 100 can be a battery module, in which a total magnetic field generating device 2 can be designed to avoid overcharging of the battery module.

[0111] Of course, the battery device 100 can also be a battery box, so that the energy storage device can achieve overcharge protection when charging. The battery cells 1 can have the structure as shown in Figure 9 Figure 10 and Figure 11 .

[0112] In any of the above embodiments, the at least part of the coil 22 can be arranged at at least one of the bottom, the side and the top of the at least one battery cell 1.

[0113] In the embodiments, the coil 22 can be arranged at the bottom, the side and the top of the battery cell 1 based on actual needs.

[0114] The second aspect of the present application provides an energy storage device, which comprises at least one battery device 100 according to any of the embodiments of the first aspect.

[0115] The energy storage device according to the present application comprises one or more battery devices 100 according to any of the embodiments of the first aspect, and thus has all the advantages of the battery device 100 according to any of the embodiments of the first aspect, which will not be repeated here.

[0116] In the above embodiments, the arrows in Figure 8 and Figure 5 represent the magnetic field.

[0117] The energy storage device according to the embodiments of the present application comprises one or more battery clusters to improve the voltage and capacity of the energy storage device. The battery cluster can comprise a plurality of battery devices 100, and the plurality of battery devices 100 are connected in series through a busbar to improve the voltage of the energy storage device. When the energy storage device comprises a plurality of battery clusters, the plurality of battery clusters are connected in parallel to improve the capacity of the energy storage device.

[0118] ​The energy storage device can be used in an energy storage power station, a wind power system, a solar power system, a mobile power system, or a temporary power supply system, etc. The energy storage device can store electric energy as needed and output the electric energy at an appropriate time. For example, the energy storage device can store electric energy during a low electricity consumption period and provide electric energy for relevant users or electric equipment during a high electricity consumption period. The energy storage system provided in the embodiments of the present application can be any power system that needs to use an energy storage device.

[0119] In some embodiments, the energy storage device is an energy storage container or an energy storage cabinet.

[0120] In some embodiments, the energy storage device can include a cabinet body and one or more battery clusters, and the battery clusters are accommodated in the cabinet body.

[0121] In some embodiments, the energy storage device can include a thermal management module, a master control module, a general control module, a power distribution module, and a fire-fighting module, etc.

[0122] As an example, the thermal management module can include a liquid cooling unit that provides cooling liquid for adjusting the temperature of the battery monomer to each battery device 100 through a pipeline.

[0123] As an example, the master control module can serve as a battery management unit of the battery cluster for monitoring and managing the battery cluster. The master control module can monitor information such as current, voltage, power, or temperature of the battery cluster. For example, the charging and discharging current and voltage of the battery cluster can be controlled. The master control module includes a slave battery management unit SBMU, a fusion switch, and other modules.

[0124] As an example, the general control module can serve as a battery management unit of the energy storage device for monitoring and managing the energy storage device. The general control module can monitor information such as current, voltage, power, state of charge, or temperature of the energy storage device. For example, the charging and discharging current and voltage of the energy storage device can be controlled. As an example, the general control module includes an insulation monitoring module IMM, a master battery management unit MBMU, an EtherNet ETH, and an optical fiber conversion module, and other modules.

[0125] As an example, the fire-fighting system includes a control panel, a detector, an alarm device, etc., for detecting, alarming, or extinguishing the energy storage system.

[0126] As an example, the power distribution device can be used for power distribution to the power consumption module of the energy storage device.

[0127] The third aspect of the present application provides an energy storage system, comprising the energy storage device in any one of the embodiments of the second aspect and a power converter system connected to the energy storage device to convert the power input into or output from the energy storage device.

[0128] The energy storage system provided by the present application has all the advantages of the energy storage device in any one of the embodiments of the second aspect, and thus will not be repeated here.

[0129] In some embodiments, as shown in Figure 16 The energy storage system can include one or more energy storage devices 200 and a power converter system 300 (PCS) for connecting between a power generation device 400 or a power grid or a load and the energy storage device 200. The power generation device 400 is used to generate power, the energy storage device 200 is used to store power, and the power converter system 300 is used to convert the power input into or output from the energy storage device 200. The power generated by the power generation device 400 can be stored in the energy storage device 200 through the power converter system 300, and the power stored in the energy storage device 200 can also be output to the load or the power grid through the power converter system 300. As an example, the power generation device 400 can be a solar panel, a hydroelectric power generation device, a thermal power generation device, a wind power generation device, etc. The specific type of the power generation device 400 is not limited in the present application.

[0130] The fourth aspect of the present application provides a charging network, comprising a charging pile; and the energy storage device in any one of the embodiments of the second aspect or the energy storage system in any one of the embodiments of the third aspect, the energy storage device being used to provide power for the charging pile.

[0131] The charging network provided by the present application has all the advantages of the energy storage device in any one of the embodiments of the second aspect or the energy storage system in any one of the embodiments of the third aspect, and thus will not be repeated here.

[0132] The charging network provided by the embodiments of the present application, as shown in Figure 17As shown, the charging pile 500 and the energy storage device 200 are electrically connected, and the energy storage device 200 is used to provide electric energy for the charging pile 500. The charging pile 500 and the battery device 100 in the energy storage device 200 are electrically connected through a cable, and the battery device 100 can provide the stored electric energy to the charging pile 500. The charging pile 500 has one or more connectors 510 for connecting with an electric equipment (such as a vehicle) so as to supply energy to the electric equipment.

[0133] The energy storage device can be located inside the charging pile (for example, a charging and storing integrated machine) or outside the charging pile.

[0134] A battery device 100 is introduced below.

[0135] The embodiment provides a battery, a magnetic variable fluid electrolyte is arranged inside the battery, and an electric current coil 22 is arranged outside the battery. The coil 22 can be distributed in a battery pack, a battery module or a battery box and is connected to a total positive and a total negative of the battery pack, the battery module or the battery box. A temperature switch is connected in series to the coil 22. In a normal use state, the coil 22 is not powered on. Once overcharging occurs in the battery, the temperature in the battery pack, the battery module or the battery box rapidly rises, the temperature switch is closed, the coil 22 is powered on to generate an electric current, a magnetic field is generated in the coil 22, the flowability of the electrolyte is reduced or even solidified in a microsecond, the polarization of the battery is improved, the cut-off voltage is reached in advance, the overcharging capacity and energy are reduced, and thermal runaway or even fire and explosion is prevented.

[0136] In a specific embodiment, the coil 22 is attached to the inner wall or the outer wall of the battery shell, and the two ends of the coil 22 are connected to the positive and negative electrodes of the battery, respectively. Meanwhile, the coil 22 is connected in series to a temperature switch. When the battery is normally used, the temperature is within a safe temperature range (negative 30℃-80℃), the temperature switch is off, and the coil 22 does not generate an electric current, which has no effect on the magnetic variable fluid electrolyte. When overcharging or other misuse occurs in the battery, the temperature of the battery rapidly rises to >80℃, the temperature switch is closed to make the coil 22 generate an electric current, a magnetic field is generated in the coil 22, the magnetic variable fluid electrolyte is affected by the magnetic field to reduce the flowability or even solidify, the polarization of the battery is improved, the cut-off voltage is reached in advance, the overcharging capacity and energy are reduced, and thermal runaway or even fire and explosion is prevented.

[0137] In another specific embodiment, the battery shell inner wall or outer wall is attached to the coil 22, and the two ends of the coil 22 are connected to the positive and negative electrodes of the battery, respectively. The coil 22 is a temperature-sensitive material coil. When the battery is normally used, the temperature is within the safe temperature range (-30℃~80℃), the resistance of the coil 22 is large within the temperature range, and the coil 22 does not generate current or generates a small current, which has little effect on the magnetic variable fluid electrolyte; when the battery is overcharged or otherwise abused, the battery temperature rises rapidly to >80℃, the resistance of the coil 22 rapidly decreases, the coil 22 generates a large current, and the generated magnetic field acts on the magnetic variable fluid electrolyte to form a magnetic field to reduce the fluidity of the electrolyte or even cause solidification, to raise the polarization of the battery, to reach the cut-off voltage in advance, to reduce the overcharge capacity and energy, and to prevent thermal runaway or even fire and explosion.

[0138] In the present embodiment, the electrolyte is a magnetic variable fluid electrolyte, and the magnetic particles 12 (soft magnetic particles) in the magnetic variable fluid electrolyte move freely in the fluid medium, which is called the magnetorheological effect. However, once the magnetic particles 12 are magnetized under a magnetic field, the magnetorheological fluid rheology rapidly changes, such as the yield stress and viscosity. That is, the magnetic particles are polarized and attracted to each other, forming a chain structure in the direction of the applied magnetic field. As shown in Figure 13 and Figure 14 As shown, under the action of a magnetic field, the magnetic particles 12 of the electrolyte immediately form a semi-solid or plastic state (as shown in Figure 13 ) from the fluid state without a magnetic field (as shown in Figure 14 ). In this semi-solid state, the magnetorheological fluid exhibits a kind of viscoplasticity. After the external magnetic field is applied, the magnetorheological polishing will rapidly change from a Newtonian fluid to a solid-like state, with a response time of milliseconds, and the change is continuous and adjustable.

[0139] Figure 14 The arrow in the figure indicates the force of the magnetic field.

[0140] For the magnetic variable fluid electrolyte, the composition includes an electrolyte and a magnetorheological component, wherein the electrolyte includes an electrolyte solvent, a lithium salt, an additive, etc.; the magnetorheological component includes micron-sized magnetic particles (soft magnetic material particles such as carbonyl iron powder, titanium-cobalt alloy, etc.), and additives (surface activity, anti-settling agent, antioxidant); the magnetic variable fluid electrolyte includes the above but is not limited to the above components, and represents all electrolytes that can change fluidity under a magnetic field.

[0141] The magnetic particles of micron level are usually selected from iron-cobalt alloy, iron-nickel alloy, carbonyl iron powder, and the like. Based on the suspension stability of the magnetorheological polishing, the commonly used magnetic particles also include high-molecular coated particles, soft-magnetic particles with core-shell structure, and the like. The dispersed phase has the following characteristics: high saturation magnetization, large magnetic permeability, low coercive force, low remanence, high physical and chemical stability, suitable particle size and shape, soft-magnetic particle density as close as possible to the carrier liquid density (to prevent rapid sedimentation), and environmentally friendly and non-toxic magnetic particles (to reduce the harm to human body). The addition range of the magnetic particles in the electrolyte is 1%wt-15%wt (i.e., the weight percentage of the magnetic particles is 1-15).

[0142] The commonly used additives are usually selected from silicon dioxide, oleic acid, linoleic acid, silane coupling agent, phosphate ester, dodecyl benzene salt, polyacrylic acid, organic bentonite, stearic acid, and other non-ionic surfactants, and the like. The additives are used to improve the flowability and suspension stability of the magnetorheological polishing. The additives include surfactants, thixotropic agents, and the like.

[0143] The performance comparison between the conventional electrolyte and the magnetorheological fluid electrolyte is shown in the following table:

[0144]

[0145] As shown in the above table, the viscosity of the magnetorheological fluid electrolyte is significantly increased after the magnetic field is applied, so that the cut-off voltage can be reached in advance, and the battery is prevented from being overcharged.

[0146] The performance of the battery device 100 after the improvement is tested, and the results are shown in Figure 12 . Figure 12 In the figures, L1 and L3 are respectively the voltage and temperature of the battery device before the improvement, and L2 and L4 are respectively the voltage and temperature of the battery device after the improvement. As shown in Figure 12 , after the improvement, the battery device is decreased from 117% SOC to 107% SOC.

[0147] The battery device in the three embodiments is introduced as follows.

[0148] First embodiment:

[0149] As shown in Figure 1 and Figure 2As shown, the battery contains a magnetically variable fluid electrolyte, and an external current coil 22 is installed. The coil 22 can be distributed within the battery pack, battery module, or battery box, and connected to the positive and negative terminals of the battery pack, battery module, or battery box. A temperature switch is connected in series with the coil 22. Under normal operating conditions, when no power is applied (temperature is between -30℃ and 80℃), if the battery is overcharged, the internal temperature of the battery pack, battery module, or battery box rises sharply (generally >80℃). The temperature switch then closes, conducting current through the coil 22, generating a magnetic field. This causes the electrolyte to reduce its fluidity or even solidify within microseconds, increasing battery polarization and reaching the cutoff voltage earlier to reduce overcharge capacity and energy, preventing thermal runaway or even fire and explosion.

[0150] The coil 22 can be located at the top, bottom or side of the battery; the number of coils 22 is ≥1; the shape of the coil 22 is not limited, generally round, square, etc.; the temperature switch is required to close when it detects abnormal battery temperature (>80℃), start the coil circuit, generate a magnetic field to act on the battery, quickly reach the overcharge protection voltage, stop charging, and at the same time reduce the heat generated by overcharging inside the battery.

[0151] The temperature switch can be adjusted according to the required safe temperature range, and is not limited to the range of (-30℃ to 80℃).

[0152] Second embodiment:

[0153] like Figure 3 , Figure 4 and Figure 5 As shown, a coil 22 is attached to the inner or outer wall of the battery casing. The two ends of the coil 22 are connected to the positive and negative terminals of the battery, respectively. A temperature switch is connected in series with the coil 22. When the battery is in normal use, the temperature is within the safe temperature range (-30℃ to 80℃). The temperature switch is open, and the coil 22 does not generate current, so it has no effect on the magnetic flux electrolyte. When the battery is overcharged or otherwise abused, the battery temperature rises rapidly to >80℃. The temperature switch closes, causing the coil 22 to generate current. The magnetic field generated acts on the magnetic flux electrolyte, reducing the fluidity of the electrolyte or even causing it to solidify. This increases battery polarization, reaches the cutoff voltage earlier, reduces overcharge capacity and energy, and prevents thermal runaway or even fire and explosion.

[0154] Optionally, the coil 22 is located on the large surface, side, bottom, or top of the battery; the number of coils 22 is ≥1; the shape of the coil 22 is not limited, generally round, square, etc.; the temperature switch can be placed on the surface or inside the battery as a miniature component, or it can be placed inside the battery pack to monitor the temperature. The temperature switch is required to close when it detects an abnormal battery temperature (>80℃), start the coil circuit, generate a magnetic field that acts on the battery, quickly reach the overcharge protection voltage, stop charging, and at the same time reduce the heat generated by overcharging inside the battery.

[0155] Temperature switches can be adjusted according to the required safety temperature range, not just the temperature range of (-30°C ~ 80°C).

[0156] Third embodiment:

[0157] As shown in Figures 6 to 10 , the battery shell inner wall or outer wall is attached to the coil 22, and the two ends of the coil 22 are connected to the positive and negative electrodes of the battery, respectively. The coil 22 is made of temperature-sensitive material. When the battery is used normally, the temperature is within the safe temperature range (-30°C ~ 80°C), the resistance of the coil 22 is large within this temperature range, and the coil 22 will not generate current or generate a small current, which has little effect on the magnetic fluid electrolyte; when the battery is overcharged or misused, the battery temperature rises rapidly to > 80°C, the resistance of the coil 22 decreases rapidly, the coil 22 generates a large current, and the magnetic field generated by the coil 22 acts on the magnetic fluid electrolyte to form a magnetic field that reduces the fluidity of the electrolyte or even causes it to solidify, thereby enhancing the polarization of the battery, reducing the overcharge capacity and energy, and preventing thermal runaway or even fire and explosion.

[0158] The coil 22 is located on the large face, side, bottom, or top of the battery, and the number of coils 22 is ≥1. The shape of the coil 22 is not limited and is generally circular or square. The material of the coil 22 is usually:

[0159] ① Negative temperature coefficient thermistor (NTC thermistor), NTC thermistor is a kind of semiconductor material, whose resistance decreases rapidly with temperature rise. This material is often used in temperature sensors, which can provide stable resistance-temperature relationship within a wide temperature range. Above 80°C, the resistance of NTC thermistor will decrease rapidly, which is suitable for applications that require temperature-sensitive resistance changes. This material can be precisely designed to meet specific temperature range and resistance change requirements.

[0160] ② Doped metal oxides, usually some doped metal oxides (such as manganese oxide, iron oxide).

[0161] They exhibit resistance changes with temperature at specific temperatures. These materials are often used in high-temperature sensors or heating elements. Applicability: Above 80°C, the resistance of these materials may decrease rapidly, depending on the type and concentration of the dopant.

[0162] ③ Conductive polymers, such as polyacetylene and polyaniline, whose conductivity can be adjusted by doping or other methods. The resistance of these materials may change significantly when the temperature changes.

[0163] The material of the coil 22 can be adjusted according to the required safety temperature range, not just the temperature range of (-30°C ~ 80°C).

[0164] In the present application, the term "a plurality" refers to two or more, unless otherwise expressly specified. The terms "mounting", "connected", "connecting", "fixed", and the like are used broadly and encompass both direct and indirect mounting, connecting, and / or fixing, as appropriate, such that "connecting" can include fixed connections, detachable connections, or integral connections; "connected" can include direct connection or indirect connection through an intermediate medium. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.

[0165] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "a specific embodiment", and the like, means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. The above is only some embodiments of the present application and is not intended to limit the present application. Those skilled in the art can make various modifications and changes to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A battery device, characterized in that, include: At least one battery cell, wherein a magnetorheological fluid electrolyte is disposed within the battery cell; A magnetic field generating device is connected to at least one of the battery cells to form an electrical circuit. The electrical circuit is capable of switching between an energized state and an de-energized state based on the temperature of at least one of the battery cells. When the electrical circuit is in the energized state, the magnetic field generating device is capable of generating a magnetic field and acting on the magnetorheological fluid electrolyte of at least one of the battery cells.

2. The battery device according to claim 1, characterized in that, Also includes: A temperature control device is used to detect the temperature of at least one of the battery cells and control whether the magnetic field generating device generates a magnetic field based on the detected temperature of at least one of the battery cells.

3. The battery device according to claim 1, characterized in that, The magnetic field generating device includes: A coil is connected to at least one of the battery cells to form an electrical circuit, the electrical circuit being able to switch between an energized state and an de-energized state based on the temperature of at least one of the battery cells. When the electrical circuit is in the energized state, the coil is able to generate a magnetic field and act on the magnetorheological fluid electrolyte of at least one of the battery cells.

4. The battery device according to claim 3, characterized in that, The magnetic field generating device further includes: A temperature control switch, connected in series in the electrical circuit, is capable of switching the on / off state of the electrical circuit based on the temperature of at least one of the battery cells, so that the electrical circuit is in the energized state or the de-energized state.

5. The battery device according to claim 3, characterized in that, The coil is a temperature-sensitive coil, which can switch the electrical circuit between the energized state and the de-energized state based on the temperature of at least one of the battery cells.

6. The battery device according to claim 3, characterized in that, The coil is connected to the positive and negative terminals of one of the battery cells to form the electrical circuit; and / or The number of battery cells is multiple, and the multiple battery cells are connected in series and / or in parallel to form at least one battery pack. At least one coil is connected to the total positive and total negative terminals of the battery pack to form the electrical circuit.

7. The battery device according to claim 3, characterized in that, Also includes: The housing has at least one of the battery cells mounted inside it, and at least a portion of the coil is mounted outside the housing and at least a portion of the coil contacts the outer wall of the housing, or the coil is mounted inside the housing and at least a portion of the coil contacts the inner wall of the housing.

8. The battery device according to any one of claims 3 to 7, characterized in that, The battery device is a battery pack, battery module, or battery box; and / or At least a portion of the coil is disposed at at least one of the bottom, side and top of at least one of the battery cells.

9. An energy storage device, characterized in that, include: At least one battery device as claimed in any one of claims 1 to 8, the battery device being used to store or provide electrical energy.

10. An energy storage system, characterized in that, include: An energy conversion system and an energy storage device as claimed in claim 9, wherein the energy conversion system is connected to the energy storage device to convert current input to or output from the energy storage device into energy.

11. A charging network, characterized in that, include: Charging stations; and The energy storage device as described in claim 9 or the energy storage system as described in claim 10, wherein the energy storage device is used to provide electrical energy to the charging pile.

Images