Battery cell and battery system

Abstract

The invention discloses a battery cell and a battery system, and belongs to the technical field of batteries. The battery cell comprises a first tab; the first pole piece can lead out an electrode through the first tab; within a first temperature range, the first switch piece has a first form, and the first tab is conductively connected with the first pole piece; and in a second temperature range, the first switch piece has a second form, and the first tab is in non-conductive connection with the first pole piece.

Description

Technical Field

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

[0002] With the continuous development of new energy technologies, the safety of battery cells has attracted more and more attention. In the prior art, in order to avoid short circuit of battery cells or electrical equipment, which may damage the battery cells and electrical equipment, a fuse is connected between the battery cells and the electrical equipment. When a short circuit occurs in the battery cell or the electrical equipment, the current flowing through the fuse increases, the temperature of the fuse rises, and the fuse will melt at high temperature, disconnecting the circuit to protect the battery cell and the electrical equipment.

[0003] However, fuses can only be used once. If a short circuit occurs, the fuse needs to be replaced after it blows, which causes great inconvenience in use and maintenance. Summary of the invention

[0004] The present application discloses a battery cell and a battery system to solve or at least partially solve the problem in the prior art that a fuse can only be used once, a short circuit problem occurs, and after the fuse blows, the fuse needs to be replaced, causing great inconvenience in use and maintenance.

[0005] In order to solve the above technical problems, this application is implemented as follows:

[0006] In a first aspect, the present application discloses a battery cell, comprising: a first pole ear; a first pole piece, through which an electrode can be led out; a first switch element, wherein within a first temperature range, the first switch element has a first form, and the first pole ear and the first pole piece are conductively connected; within a second temperature range, the first switch element has a second form, and the first pole ear and the first pole piece are non-conductively connected.

[0007] Optionally, at least a portion of the first switch element is made of shape memory alloy.

[0008] Optionally, the first switch element includes: a first contact end, the first contact end is connected to the first pole ear; a second contact end, the second contact end is connected to the first pole piece; the first contact end and / or the second contact end are made of shape memory alloy.

[0009] Optionally, the resistance of the first contact end is R1=ρ1*L1 / S1, wherein the length of the first contact end is L1, the cross-sectional area of ​​the first contact end is S1, and the resistivity of the shape memory alloy in the first contact end is ρ1; and / or the resistance of the second contact end is R2=ρ2*L2 / S2, wherein the length of the second contact end is L2, the cross-sectional area of ​​the second contact end is S2, and the resistivity of the shape memory alloy in the second contact end is ρ2.

[0010] Optionally, the resistance of the first contact end is R3=c3*m3*△T3 / I3*t3, wherein the specific heat capacity of the shape memory alloy in the first contact end is c3, the mass of the first contact end is m3, the temperature value change of the first contact end is △T3, the short-circuit current flowing through the first contact end is I3, and the duration of the short-circuit current flowing through the first contact end is t3; and / or, the resistance of the second contact end is R4=c4*m4*△T4 / I4*t4, wherein the specific heat capacity of the shape memory alloy in the second contact end is c4, the mass of the second contact end is m4, the temperature value change of the second contact end is △T4, the short-circuit current flowing through the second contact end is I4, and the duration of the short-circuit current flowing through the second contact end is t4.

[0011] Optionally, the specific heat capacity of the shape memory alloy in the first switch component is c5=R5*I52*t5 / m5*△T5, wherein the mass of the shape memory alloy in the first switch component is m5, the temperature value change of the shape memory alloy in the first switch component is △T5, the short-circuit current flowing through the shape memory alloy in the first switch component is I5, the time duration of the short-circuit current flowing through the shape memory alloy in the first switch component is t5, and the resistance of the shape memory alloy in the first switch component is R5.

[0012] Optionally, the resistance of the shape memory alloy in the first switch component is R6=ρ6*L6 / S6, wherein the length of the shape memory alloy in the first switch component is L6, the cross-sectional area of ​​the shape memory alloy in the first switch component is S6, and the resistivity of the shape memory alloy in the first switch component is ρ6.

[0013] Optionally, the first switch element has a first initial state, and when a temperature value of the first switch element is less than or equal to a first preset temperature, the first switch element switches from the first initial state to the first state.

[0014] Optionally, the first preset temperature is less than or equal to 45 degrees.

[0015] Optionally, the first switch element has a first initial state, and when a temperature value of the first switch element is greater than or equal to a second preset temperature, the first switch element switches from the first initial state to the second state.

[0016] Optionally, the second preset temperature is greater than or equal to 150 degrees.

[0017] Optionally, the battery cell further includes: a second pole ear; a second pole piece, through which an electrode can be led out of the second pole piece; and an insulating layer is provided between the first pole piece and the second pole piece.

[0018] Optionally, a second switching element is connected between the second pole ear and the second pole piece; within a third temperature range, the second switching element has a third form, and the second pole ear and the second pole piece are conductively connected; within a fourth temperature range, the second switching element has a fourth form, and the second pole ear and the second pole piece are non-conductively connected.

[0019] Optionally, at least a portion of the second switch element is made of shape memory alloy.

[0020] Optionally, the second switch element includes: a third contact terminal, the third contact terminal is connected to the second pole ear; a fourth contact terminal, the fourth contact terminal is connected to the second pole piece; the third contact terminal and / or the fourth contact terminal are made of shape memory alloy.

[0021] In a second aspect, the present application further discloses a battery system, which includes: an electrical device; and the battery cell described in the first aspect, wherein the electrical device is electrically connected to the first electrode.

[0022] The present application discloses a battery cell and a battery system, wherein the battery cell comprises a first pole ear; a first pole piece, through which an electrode can be led out; a first switch element, wherein within a first temperature range, the first switch element has a first form, and the first pole ear and the first pole piece are conductively connected; within a second temperature range, the first switch element has a second form, and the first pole ear and the first pole piece are non-conductively connected.

[0023] The battery cell disclosed in the present application includes a first pole ear, a first pole piece and a first switch, wherein the first pole piece leads out an electrode through the first pole ear, and within a first temperature range, the first switch has a first form so that the first pole ear and the first pole piece are conductively connected, and within a second temperature range, the first switch has a second form so that the first pole ear and the first pole piece are non-conductively connected. Through the above arrangement, the first pole ear and the first pole piece can be switched between conductive connection and non-conductive connection to protect the battery cell.

[0024] Furthermore, the first switch can be switched between the first state and the second state, so that the first pole piece and the first pole tab are conductively connected or the first pole piece and the first pole tab are non-conductively connected. In other words, the first switch can be used repeatedly, which helps to reduce the inconvenience of using and maintaining the battery cell and improve the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A diagram showing the working principle of the battery system described in the embodiment of the present application;

[0026] Figure 2 A cross-sectional view showing a battery cell according to an embodiment of the present application;

[0027] Figure 3 A schematic diagram showing a structure in which the first switch element or the second switch element is in a closed state in an embodiment of the present application;

[0028] Figure 4 A schematic structural diagram showing that the first switch element or the second switch element is in a disconnected state in an embodiment of the present application.

[0029] Reference numerals:

[0030] 10: battery cell; 11: first pole piece; 12: first pole tab; 13: second pole piece; 14: second pole tab; 15: battery cell body; 16: housing; 17: diaphragm;

[0031] 20: first switch element; 21: first contact terminal; 22: second contact terminal;

[0032] 30: insulation layer;

[0033] 40: Electrical equipment;

[0034] 50: second switch element; 51: third contact terminal; 52: fourth contact terminal. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] It should be understood that the references to "one embodiment" or "an embodiment" throughout the specification mean that the specific features, structures, or characteristics associated with the embodiment are included in at least one embodiment of the present invention. Therefore, the references to "in one embodiment" or "in an embodiment" appearing throughout the specification do not necessarily refer to the same embodiment. In addition, these specific features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0037] Reference Figure 1 , which shows a working principle diagram of the battery system described in the embodiment of the present application; refer to Figure 2 , showing a cross-sectional view of the battery cell described in the embodiment of the present application; referring to Figure 3 , showing a schematic structural diagram of the first switch element or the second switch element in a closed state in an embodiment of the present application; referring to Figure 4 , shows a structural schematic diagram of the first switch component or the second switch component in a disconnected state in an embodiment of the present application.

[0038] like Figure 2 As shown, an embodiment of the present application discloses a battery cell 10, which includes a first pole ear 12; a first pole piece 11, through which an electrode of the first pole piece 11 can be led out; a first switch element 20, wherein within a first temperature range, the first switch element 20 has a first form, and the first pole ear 12 and the first pole piece 11 are conductively connected; within a second temperature range, the first switch element 20 has a second form, and the first pole ear 12 and the first pole piece 11 are non-conductively connected.

[0039] The embodiment of the present application discloses a battery cell 10, which includes a first pole piece 11. The first pole piece 11 can be a positive pole of the battery cell 10 or a negative pole of the battery cell 10. In the embodiment of the present application, there are no excessive restrictions on whether the first pole piece 11 is a positive pole of the battery cell 10 or a negative pole of the battery cell 10. In actual applications, technicians can set it as needed.

[0040] The following will take the first pole piece 11 as the positive pole of the battery cell 10 as an example to explain the embodiments of the present application.

[0041] like Figure 2 As shown, the first pole piece 11 can lead out the electrode through the first pole ear 12. It can be understood that the first pole ear 12 is exposed to the battery cell 10, and the first pole piece 11 leads out the positive electrode of the battery cell 10 through the first pole ear 12, so as to connect the battery cell 10 to the electrical device 40 through the first pole ear 12 to supply power to the electrical device 40.

[0042] In the embodiment of the present application, a first switch 20 is provided between the first pole piece 11 and the first pole ear 12, and the first switch 20 can switch between the first form and the second form according to its own temperature value. The first form and the first form are different forms of the first switch 20. When the first switch 20 is within the first temperature range, the first switch 20 has the first form, and the first pole piece 11 and the first pole ear 12 are conductively connected. When the first switch 20 is within the second temperature range, the first switch 20 has the second form, and the first pole piece 11 and the first pole ear 12 are non-conductively connected.

[0043] It should be noted that the first form and the second form of the first switch element 20 in the embodiment of the present application are different forms. For example, the first form may be a closed form, and the second form may be a disconnected form. The first form may be a planar form, and the second form may be a curved form. In the embodiment of the present application, there are no excessive restrictions on the specific structures of the first form and the second form. The following will take the first form as a closed form and the second form as a disconnected form as an example to explain the embodiment of the present application.

[0044] At least part of the first switch 20 can sense its own temperature and switch between a closed state and an open state according to its own temperature value. When the first switch 20 is within the first temperature range, the first switch 20 is in a closed state, the first switch 20 connects the first pole piece 11 and the first pole lug 12, and the first pole piece 11 and the first pole lug 12 are conductive. When the first switch 20 is within the second temperature range, the first switch 20 is in an open state, and the first pole piece 11 and the first pole lug 12 are not conductive.

[0045] It should be noted that the non-conductive connection between the first pole piece 11 and the first pole lug 12 in the embodiment of the present application means that there is no conduction between the first pole piece 11 and the first pole lug 12, and there is no electrical connection between the first pole piece 11 and the first pole lug 12. In other words, any method that can make the first pole piece 11 and the first pole lug 12 non-conductively connected belongs to the protection scope of the present application. Exemplarily, the first pole lug 11 and the first pole lug 12 are disconnected. The following will take the disconnection of the first pole piece 11 and the first pole lug 12 as an example to explain the present application.

[0046] The first temperature range and the second temperature range may be the temperature range of the first switch itself, or the temperature range of the surrounding environment of the first switch or the temperature of the battery cell. This embodiment is preferably the temperature range of the first switch itself.

[0047] Exemplarily, the first switch element 20 includes a first contact terminal 21 and a second contact terminal 22. The first contact terminal 21 is made of a common conductive material, such as copper, aluminum, etc. The second contact terminal 22 is made of a shape memory alloy material. The first contact terminal 21 is connected to the first pole ear 12, and the second contact terminal 22 is connected to the first pole piece 11.

[0048] In the first initial state, the second contact end 22 is away from the first pole piece 11, and the first switch element 20 is in an open state. When the current flowing through the second contact end 22 changes, and the second contact end 22 senses that its own temperature value is less than or equal to the first preset temperature, the second contact end 22 deforms and abuts against the first pole piece 11, thereby changing the first switch element 20 into a closed state.

[0049] In the first initial state, the second contact end 22 abuts against the first pole piece 11, and the first switch element 20 is in a closed state. When the current flowing through the second contact end 22 changes, and the second contact end 22 senses that its own temperature value is greater than or equal to the second preset temperature, the second contact end 22 deforms and moves away from the first pole piece 11, thereby changing the first switch element 20 to an open state.

[0050] It should be noted that the first preset temperature and the second preset temperature in the embodiment of the present application are set by technicians as needed. In the embodiment of the present application, there are no excessive restrictions on the specific temperature values ​​of the first preset temperature and the second preset temperature.

[0051] The battery cell 10 disclosed in the present application includes a first pole ear 12, a first pole piece 11 and a first switch 20. The first pole piece 11 leads out an electrode through the first pole ear 12. In a first temperature range, the first switch 20 has a first form so that the first pole ear 12 and the first pole piece 11 are conductively connected. In a second temperature range, the first switch 20 has a second form so that the first pole ear 12 and the first pole piece 11 are non-conductively connected. Through the above arrangement, the first pole ear 12 and the first pole piece 11 can be switched between conductive connection and non-conductive connection to protect the battery cell 10.

[0052] Furthermore, the first switch 20 can switch between the first state and the second state, so that the first pole piece 11 and the first pole tab 12 are conductively connected or the first pole piece 11 and the first pole tab 12 are non-conductively connected. In other words, the first switch 20 can be used repeatedly, which helps to reduce the inconvenience of using and maintaining the battery cell 10 and improve the user experience.

[0053] Alternatively, if Figures 2 to 4 As shown, at least a portion of the first switch element 20 in the embodiment of the present application is made of shape memory alloy.

[0054] It should be noted that, in the embodiment of the present application, at least part of the first switch member 20 is made of shape memory alloy. Shape memory alloy (SMA for short) is an alloy material that can completely eliminate its deformation at a lower temperature and restore its original shape before deformation after heating, that is, an alloy with a "memory" effect.

[0055] For example, the shape memory alloy in the embodiment of the present application can be a TiNi-based shape memory alloy, a copper-based shape memory alloy, an iron-based shape memory alloy, etc. In the embodiment of the present application, there are no excessive restrictions on the specific type of the shape memory alloy. In practical applications, technicians can select as needed.

[0056] like Figures 2 to 4 As shown, the first switch element 20 in the embodiment of the present application includes a first contact terminal 21 and a second contact terminal 22. The first contact terminal 21 is made of a common conductive material, and the second contact terminal 22 is made of a shape memory alloy. Alternatively, the first contact terminal 21 is made of a shape memory alloy, and the second contact terminal 22 is made of a common conductive material. Alternatively, both the first contact terminal 21 and the second contact terminal 22 are made of a shape memory alloy.

[0057] In the embodiment of the present application, by making at least a portion of the first switch element 20 using a shape memory alloy, the shape memory alloy of the first switch element 20 can be repeatedly used during the process of switching between the closed state and the open state, thereby helping to reduce the inconvenience of using and maintaining the battery cell 10 and improving the user experience.

[0058] Alternatively, if Figures 2 to 4 As shown, the first switch element 20 in the embodiment of the present application includes a first contact terminal 21, which is connected to the first pole ear 12; a second contact terminal 22, which is connected to the first pole piece 11; the first contact terminal 21 and / or the second contact terminal 22 are made of shape memory alloy.

[0059] like Figures 2 to 4As shown, the first switch element 20 in the embodiment of the present application includes a first contact terminal 21 and a second contact terminal 22, and both the first contact terminal 21 and the second contact terminal 22 are conductive. Exemplarily, the first contact terminal 21 is made of a common conductive material, such as copper, aluminum, etc. The second contact terminal 22 is made of a shape memory alloy. Since the second contact terminal 22 is made of a shape memory alloy, the second contact terminal 22 can switch its form according to its own temperature value. When the temperature value of the second contact terminal 22 is within the first temperature range, the second contact terminal 22 switches to a closed form abutting against the first pole piece 11. When the temperature value of the second contact terminal 22 is within the second temperature range, the second contact terminal 22 switches to a disconnected form away from the first pole piece 11.

[0060] Exemplarily, the first contact terminal 21 is made of a shape memory alloy, and the second contact terminal 22 is made of a common conductive material, such as copper, aluminum, etc. Since the first contact terminal 21 is made of a shape memory alloy, the first contact terminal 21 can switch its form according to its own temperature value. When the temperature value of the first contact terminal 21 is within the first temperature range, the first contact terminal 21 switches to a closed form abutting against the first pole lug 12. When the temperature of the first contact terminal 21 is within the second temperature range, the first contact terminal 21 switches to an open form away from the first pole lug 12.

[0061] Of course, the first contact end 21 and the second contact end 22 may also be made of shape memory alloy, which will not be described in detail herein.

[0062] Optionally, in an embodiment of the present application, the resistance of the first contact terminal 21 is R1, the length of the first contact terminal 21 is L1, the cross-sectional area of ​​the first contact terminal 21 is S1, and the resistivity of the shape memory alloy in the first contact terminal 21 is ρ1, satisfying R1=ρ1*L1 / S1; and / or, the resistance of the second contact terminal 22 is R2, the length of the second contact terminal 22 is L2, the cross-sectional area of ​​the second contact terminal 22 is S2, and the resistivity of the shape memory alloy in the second contact terminal 22 is ρ2, satisfying R2=ρ2*L2 / S2.

[0063] In the embodiment of the present application, the resistance of the first contact terminal 21 is set to R1, the length of the first contact terminal 21 is set to L1, the cross-sectional area of ​​the first contact terminal 21 is set to S1, and the resistivity of the shape memory alloy in the first contact terminal 21 is set to ρ1, satisfying R1=ρ1*L1 / S1. When the specific type of the shape memory alloy selected for the first contact terminal 21 is determined, the resistivity ρ1 of the shape memory alloy can be determined, and according to R1=ρ1*L1 / S1, the relationship between the length L1 of the first contact terminal 21 and the cross-sectional area S1 of the first contact terminal 21 is determined, thereby determining the specific structure of the first contact terminal 21.

[0064] Similarly, the resistance of the second contact terminal 22 is set to R2, the length of the second contact terminal 22 is set to L2, the cross-sectional area of ​​the second contact terminal 22 is set to S2, and the resistivity of the shape memory alloy in the second contact terminal 22 is set to ρ2, satisfying R2=ρ2*L2 / S2. When the specific type of the shape memory alloy selected for the second contact terminal 22 is determined, the resistivity ρ2 of the shape memory alloy can be determined, and according to R2=ρ2*L2 / S2, the relationship between the length L2 of the second contact terminal 22 and the cross-sectional area S2 of the second contact terminal 22 is determined, thereby determining the specific structure of the second contact terminal 22.

[0065] Optionally, the resistance of the first contact terminal 21 is R3, the specific heat capacity of the shape memory alloy in the first contact terminal 21 is c3, the mass of the first contact terminal 21 is m3, the temperature value change of the first contact terminal 21 is △T3, the short-circuit current flowing through the first contact terminal 21 is I3, and the time duration of the short-circuit current flowing through the first contact terminal 21 is t3, satisfying R3=c3*m3*△T3 / I3 2 *t3; and / or, the resistance of the second contact terminal 22 is R4, the specific heat capacity of the shape memory alloy in the second contact terminal 22 is c4, the mass of the second contact terminal 22 is m4, the temperature value change of the second contact terminal 22 is △T4, the short-circuit current flowing through the second contact terminal 22 is I4, and the time duration of the short-circuit current flowing through the second contact terminal 22 is t4, satisfying R4=c4*m4*△T4 / I4 2 *t4.

[0066] In order to make the first contact terminal 21 deform at the second preset temperature to move away from the first pole ear 12 and be in a disconnected state. In the embodiment of the present application, the resistance of the first contact terminal 21 is set to R3, the specific heat capacity of the shape memory alloy in the first contact terminal 21 is set to c3, the mass of the first contact terminal 21 is set to m3, the temperature value change of the first contact terminal 21 is set to △T3, the short-circuit current flowing through the first contact terminal 21 is set to I3, and the duration of the short-circuit current flowing through the first contact terminal 21 is set to t3, satisfying R3=c3*m3*△T3 / I3 2 * t3. Through the above arrangement, the first contact end 21 can be deformed at the second preset temperature to be away from the first pole ear 12 and be in a disconnected state, thereby protecting the battery cell 10.

[0067] Similarly, in order to make the second contact terminal 22 deform at the second preset temperature to move away from the first pole piece 11 and be in a disconnected state. In the embodiment of the present application, the resistance of the second contact terminal 22 is set to R4, the specific heat capacity of the shape memory alloy in the second contact terminal 22 is set to c4, the mass of the second contact terminal 22 is set to m4, the temperature value change of the second contact terminal 22 is set to △T4, the short-circuit current flowing through the second contact terminal 22 is set to I4, and the duration of the short-circuit current flowing through the second contact terminal 22 is set to t4, satisfying R4=c4*m4*△T4 / I4 2 * t4. Through the above arrangement, the second contact end 22 can be deformed at the second preset temperature to be away from the first pole piece 11 and be in a disconnected state, thereby protecting the battery cell 10.

[0068] Optionally, in an embodiment of the present application, the specific heat capacity of the shape memory alloy in the first switch component 20 is c5, the mass of the shape memory alloy in the first switch component 20 is m5, the temperature value change of the shape memory alloy in the first switch component 20 is △T5, the short-circuit current flowing through the shape memory alloy in the first switch component 20 is I5, the time duration of the short-circuit current flowing through the shape memory alloy in the first switch component 20 is t5, and the resistance of the shape memory alloy in the first switch component 20 is R5, satisfying c5=R5*I52*t5 / m5*△T5.

[0069] In the embodiment of the present application, the specific heat capacity of the shape memory alloy in the first switch 20 is set to c5, the mass of the shape memory alloy in the first switch 20 is set to m5, the temperature value change of the shape memory alloy in the first switch 20 is set to △T5, the short-circuit current flowing through the shape memory alloy in the first switch 20 is set to I5, the time duration of the short-circuit current flowing through the shape memory alloy in the first switch 20 is set to t5, and the resistance of the shape memory alloy in the first switch 20 is set to R5, satisfying c5=R5*I52*t5 / m5*△T5. Through the above settings, the specific heat capacity c5 of the shape memory alloy in the first switch 20 is determined, so as to facilitate the determination of the specific type of the shape memory alloy.

[0070] Optionally, the resistance R6 of the shape memory alloy in the first switch element 20 is ρ6*L6 / S6, wherein the length of the shape memory alloy in the first switch element 20 is L6, the cross-sectional area of ​​the shape memory alloy in the first switch element 20 is S6, and the resistivity of the shape memory alloy in the first switch element 20 is ρ6.

[0071] In the embodiment of the present application, the resistance of the shape memory alloy in the first switch 20 is set to R6, the length of the shape memory alloy in the first switch 20 is set to L6, the cross-sectional area of ​​the shape memory alloy in the first switch 20 is set to S6, and the resistivity of the shape memory alloy in the first switch 20 is set to ρ6, satisfying R6=ρ6*L6 / S6. When the specific type of the shape memory alloy selected in the first switch 20 is determined, the resistivity ρ6 of the shape memory alloy can be determined, and according to R6=ρ6*L6 / S6, the relationship between the length L6 of the shape memory alloy in the first switch 20 and the cross-sectional area S6 of the shape memory alloy in the first switch 20 is determined, thereby determining the specific structure of the shape memory alloy in the first switch 20.

[0072] Alternatively, if Figure 3 and Figure 4 As shown, the first switch element 20 in the embodiment of the present application has a first initial state. When the temperature value of the first switch element 20 is less than or equal to the first preset temperature, the first switch element 20 switches from the first initial state to the first state.

[0073] like Figure 3 and Figure 4 As shown, the first switch element 20 has a first initial state, which can be a closed state or an open state.

[0074] Exemplarily, when the first initial state of the first switch element 20 is the disconnected state, when the temperature value of the first switch element 20 itself is less than or equal to the first preset temperature, the first switch element 20 switches from the disconnected state to the closed state, conductively connecting the first pole ear 12 with the first pole piece 11, so that the battery cell 10 can operate normally.

[0075] Exemplarily, when the first contact terminal 21 is made of a common conductive material and the second contact terminal 22 is made of a shape memory alloy, in the first initial state, the second contact terminal 22 is in a disconnected state away from the first pole piece 11. When the temperature value of the second contact terminal 22 itself is less than or equal to the first preset temperature, the second contact terminal 22 switches from the disconnected state away from the first pole piece 11 to the closed state abutting against the first pole piece 11, and the first pole ear 12 is conductively connected to the first pole piece 11, so that the battery cell 10 can work normally.

[0076] It should be noted that the first preset temperature in the embodiment of the present application is designed by the technicians in the design process according to actual needs. In the embodiment of the present application, there are no excessive restrictions on the specific value of the first preset temperature. For example, the first preset temperature can be 40 degrees, 43 degrees, 45 degrees, 47 degrees, 50 degrees, etc.

[0077] In the embodiment of the present application, when the temperature value of the first switch 20 itself is less than or equal to the first preset temperature, the first switch 20 can be switched from the first initial state to the first state, so that the first switch 20 can be used repeatedly, thereby helping to reduce the inconvenience of using and maintaining the battery cell 10 and improving the user experience.

[0078] Preferably, the first preset temperature in the embodiment of the present application is less than or equal to 45 degrees.

[0079] As a preferred embodiment, in the embodiment of the present application, the first preset temperature is set to be less than or equal to 45 degrees. Exemplarily, the first preset temperature can be 45 degrees, the first preset temperature can be 43 degrees, and the first preset temperature can also be 40 degrees. Of course, the first preset temperature in the embodiment of the present application can also be any other value less than or equal to 45 degrees. In this regard, the embodiment of the present application does not make specific restrictions, and in actual applications, technicians can set it as needed.

[0080] Alternatively, if Figure 3 and Figure 4 As shown, the first switch element 20 has a first initial state. When the temperature value of the first switch element 20 is greater than or equal to a second preset temperature, the first switch element 20 switches from the first initial state to the second state.

[0081] like Figure 3 and Figure 4 As shown, the first switch element 20 has a first initial state, which can be a closed state or an open state.

[0082] Exemplarily, when the first initial state of the first switch element 20 is a closed state, when the temperature value of the first switch element 20 itself is greater than or equal to a second preset temperature, the first switch element 20 switches from a closed state to an open state to disconnect the first pole ear 12 from the first pole piece 11, thereby protecting the battery cell 10.

[0083] Exemplarily, when the first contact terminal 21 is made of a common conductive material and the second contact terminal 22 is made of a shape memory alloy, in the first initial state, the second contact terminal 22 is in a closed state abutting against the first pole piece 11. When the temperature value of the second contact terminal 22 itself is greater than or equal to the second preset temperature, the second contact terminal 22 switches from a closed state abutting against the first pole piece 11 to a disconnected state away from the first pole piece 11, so that the first pole ear 12 is disconnected from the first pole piece 11, thereby protecting the battery cell 10.

[0084] It should be noted that the second preset temperature in the embodiment of the present application is designed by the technicians in the design process according to the actual needs. In the embodiment of the present application, there are no excessive restrictions on the specific value of the second preset temperature. For example, the second preset temperature can be 145 degrees, 147 degrees, 150 degrees, 153 degrees, 155 degrees, etc.

[0085] In the embodiment of the present application, when the temperature value of the first switch element 20 is greater than or equal to the second preset temperature, the first switch element 20 switches from the first initial state to the second state to disconnect the first pole ear 12 from the first pole piece 11, thereby protecting the battery cell 10.

[0086] Preferably, the second preset temperature is greater than or equal to 150 degrees.

[0087] As a preferred implementation, in the embodiment of the present application, the second preset temperature is set to be greater than or equal to 150 degrees. Exemplarily, the second preset temperature can be 150 degrees, the second preset temperature can be 153 degrees, and the second preset temperature can also be 155 degrees. Of course, the second preset temperature in the embodiment of the present application can also be any value greater than or equal to 150 degrees. In this regard, the embodiment of the present application does not make specific restrictions, and in actual applications, technicians can set it as needed.

[0088] The following will take the example that the first contact end 21 is made of ordinary conductive material, the second contact end 22 is made of shape memory alloy, the first preset temperature is 45 degrees, and the second preset temperature is 150 degrees to explain the embodiments of the present application.

[0089] When the battery cell 10 is working normally, the temperature of the battery cell 10 is less than or equal to 45 degrees. The second contact end 22 of the first switch 20 abuts against the first pole piece 11, and the first switch 20 is in a closed state. If an abnormality occurs inside the battery cell 10, the current flowing through the second contact end 22 increases. Due to the resistance of the second contact end 22 itself, the second contact end 22 heats up, and the temperature value of the second contact end 22 itself rises sharply. When the temperature value of the second contact end 22 reaches 150 degrees, the second contact end 22 deforms, the second contact end 22 moves away from the first pole piece 11, and the first switch 20 is in a disconnected state to protect the battery cell 10. After the abnormality inside the battery cell 10 is resolved, the current flowing through the second contact end 22 decreases, and the temperature of the second contact end 22 gradually decreases. When the temperature drops to 45 degrees, the second contact end 22 deforms, the second contact end 22 abuts against the first pole piece 11, the first switch 20 is in a closed state, and the battery cell 10 can continue to work normally.

[0090] Alternatively, if Figure 2As shown, the battery cell 10 disclosed in the embodiment of the present application further includes a second pole ear 14 ; a second pole piece 13 , through which the electrode of the second pole piece 13 can be led out; and an insulating layer 30 is disposed between the first pole piece 11 and the second pole piece 13 .

[0091] like Figure 2 As shown, the battery cell 10 disclosed in the embodiment of the present application further includes a second pole piece 13. When the first pole piece 11 is the positive pole of the battery cell 10, the second pole piece 13 is the negative pole of the battery cell 10. When the first pole piece 11 is the negative pole of the battery cell 10, the second pole piece 13 is the positive pole of the battery cell 10.

[0092] The following description will be made of the first pole piece 11 as the positive pole of the battery cell 10 and the second pole piece 13 as the negative pole of the battery cell 10 as an example to explain the embodiments of the present application.

[0093] In the embodiment of the present application, the first electrode 11 can store and release charges, and the active material is generally lithium manganese oxide, lithium cobalt oxide or lithium iron phosphate, etc., which is related to the type of the battery cell 10. The second electrode 13 is used to store charges and is generally made of graphite.

[0094] like Figure 2 As shown, the first pole piece 11 leads the positive electrode of the battery cell 10 through the first pole ear 12, and the second pole piece 13 leads the negative electrode of the battery cell 10 through the second pole ear 14. The first pole ear 12 and the second pole ear 14 are both exposed to the battery cell 10, so that the battery cell 10 is connected to the electrical device 40 through the first pole ear 12 and the second pole ear 14 to supply power to the electrical device 40.

[0095] In the embodiment of the present application, an insulating layer 30 is disposed between the first pole piece 11 and the second pole piece 13 , so as to block the first pole piece 11 and the second pole piece 13 through the insulating layer 30 , thereby preventing the battery cell 10 from leaking electricity.

[0096] It should be noted that the insulating layer 30 in the embodiment of the present application has insulating properties. Exemplarily, the insulating layer 30 can be an insulating rubber layer. Of course, in the embodiment of the present application, there are no excessive restrictions on the specific material of the insulating layer 30. In actual applications, technicians can choose according to needs.

[0097] Optionally, in an embodiment of the present application, a second switch element 50 is connected between the second pole ear 14 and the second pole piece 13; within a third temperature range, the second switch element 50 has a third form, and the second pole ear 14 and the second pole piece 13 are conductively connected; within a fourth temperature range, the second switch element 50 has a fourth form, and the second pole ear 14 and the second pole piece 13 are non-conductively connected.

[0098] like Figures 2 to 4As shown, the second pole piece 13 can lead out the electrode through the second pole ear 14. It can be understood that the second pole ear 14 is exposed to the battery cell 10, and the second pole piece 13 leads out the negative electrode of the battery cell 10 through the second pole ear 14, so as to connect the battery cell 10 to the electrical device 40 through the second pole ear 14 to supply power to the electrical device 40.

[0099] In the embodiment of the present application, a second switch 50 is disposed between the second pole piece 13 and the second pole ear 14 , and the second switch 50 can switch between the third state and the fourth state according to its own temperature value. The third state and the fourth state are different states of the first switch 20 .

[0100] When the second switch element 50 is within the third temperature range, the second switch element 50 has a third state, and the second pole piece 13 is conductively connected to the second pole tab 14. When the second switch element 50 is within the fourth temperature range, the second switch element 50 has a fourth state, and the second pole piece 13 is non-conductively connected to the second pole tab 14.

[0101] It should be noted that the third form and the fourth form of the second switch element 50 in the embodiment of the present application are different forms. Exemplarily, the third form may be a closed form, and the fourth form may be a disconnected form. The third form may be a planar form, and the fourth form may be a curved form. In the embodiment of the present application, there are no excessive restrictions on the specific structures of the third form and the fourth form. The following will take the third form as a closed form and the fourth form as a disconnected form as an example to explain the embodiment of the present application.

[0102] At least part of the second switch 50 can sense its own temperature and switch between a closed state and an open state according to its own temperature value. When the second switch 50 is within the third temperature range, the second switch 50 is in a closed state, the second switch 50 connects the second pole piece 13 and the second pole lug 14, and the second pole piece 13 and the second pole lug 14 are conductive. When the second switch 50 is within the fourth temperature range, the second switch 50 is in an open state, the second switch 50 disconnects the connection between the second pole piece 13 and the second pole lug 14, and the second pole piece 13 and the second pole lug 14 are not conductive.

[0103] It should be noted that the non-conductive connection between the second pole piece 13 and the second pole lug 14 in the embodiment of the present application means that there is no conduction between the second pole piece 13 and the second pole lug 14, and there is no electrical connection between the second pole piece 13 and the second pole lug 14. In other words, any method that can make the second pole piece 13 and the second pole lug 14 non-conductively connected belongs to the protection scope of the present application. Exemplarily, the second pole piece 13 and the second pole lug 14 are disconnected. The following will take the disconnection of the second pole piece 13 and the second pole lug 14 as an example to explain the present application.

[0104] It should be noted that the third preset temperature and the fourth preset temperature in the embodiment of the present application are set by technicians as needed. In the embodiment of the present application, there are no excessive restrictions on the specific temperature values ​​of the third preset temperature and the fourth preset temperature.

[0105] The second pole piece 13 in the embodiment of the present application leads out the electrode through the second pole ear 14. In the third temperature range, the second switch 50 has a third form to make the second pole ear 14 and the second pole piece 13 conductively connected. In the second temperature range, the second switch 50 has a fourth form to make the second pole ear 14 and the second pole piece 13 non-conductively connected. Through the above arrangement, the second pole ear 14 and the second pole piece 13 can be switched between conductive connection and non-conductive connection to protect the battery cell 10.

[0106] Furthermore, the second switch 50 can be switched between the third state and the fourth state, so that the second pole piece 13 and the second pole tab 14 are conductively connected or the second pole piece 13 and the second pole tab 14 are non-conductively connected. In other words, the second switch 50 can be used repeatedly, which helps to reduce the inconvenience of using and maintaining the battery cell 10 and improve the user experience.

[0107] Alternatively, if Figures 2 to 4 As shown, at least a portion of the second switch element 50 in the embodiment of the present application is made of shape memory alloy.

[0108] It should be noted that, in the embodiment of the present application, at least part of the second switch element 50 is made of shape memory alloy. Shape memory alloy (SMA for short) is an alloy material that can completely eliminate its deformation at a lower temperature and restore its original shape before deformation after heating, that is, an alloy with a "memory" effect.

[0109] For example, the shape memory alloy in the embodiment of the present application can be a TiNi-based shape memory alloy, a copper-based shape memory alloy, an iron-based shape memory alloy, etc. In the embodiment of the present application, there are no excessive restrictions on the specific type of the shape memory alloy. In practical applications, technicians can select as needed.

[0110] like Figures 2 to 4 As shown, the second switch element 50 in the embodiment of the present application includes a third contact terminal 51 and a fourth contact terminal 52. The third contact terminal 51 is made of a common conductive material, and the fourth contact terminal 52 is made of a shape memory alloy. Alternatively, the third contact terminal 51 is made of a shape memory alloy, and the fourth contact terminal 52 is made of a common conductive material. Alternatively, both the third contact terminal 51 and the fourth contact terminal 52 are made of a shape memory alloy.

[0111] In the embodiment of the present application, by making at least a portion of the second switch element 50 with a shape memory alloy, the shape memory alloy of the second switch element 50 can be repeatedly used during the process of switching between the closed state and the open state, thereby helping to reduce the inconvenience of using and maintaining the battery cell 10 and improving the user experience.

[0112] Alternatively, if Figures 2 to 4 As shown, the second switch element 50 in the embodiment of the present application includes a third contact terminal 51, which is connected to the second pole ear 14; a fourth contact terminal 52, which is connected to the second pole piece 13; the third contact terminal 51 and / or the fourth contact terminal 52 are made of shape memory alloy.

[0113] like Figures 2 to 4 As shown, the second switch element 50 in the embodiment of the present application includes a third contact terminal 51 and a fourth contact terminal 52, and the third contact terminal 51 and the fourth contact terminal 52 are both conductive. Exemplarily, the third contact terminal 51 is made of a common conductive material, such as copper, aluminum, etc. The fourth contact terminal 52 is made of a shape memory alloy. Since the fourth contact terminal 52 is made of a shape memory alloy, the fourth contact terminal 52 can switch its form according to its own temperature value. When the temperature value of the fourth contact terminal 52 is within the third temperature range, the fourth contact terminal 52 switches to a closed form abutting against the second pole piece 13. When the temperature value of the fourth contact terminal 52 is within the fourth temperature range, the fourth contact terminal 52 switches to a disconnected form away from the second pole piece 13.

[0114] Exemplarily, the third contact terminal 51 is made of a shape memory alloy, and the fourth contact terminal 52 is made of a common conductive material, such as copper, aluminum, etc. Since the third contact terminal 51 is made of a shape memory alloy, the third contact terminal 51 can switch its form according to its own temperature value. When the temperature value of the third contact terminal 51 is within the third temperature range, the third contact terminal 51 switches to a closed form abutting against the second pole lug 14. When the temperature of the third contact terminal 51 is within the second temperature range, the third contact terminal 51 switches to a disconnected form away from the second pole lug 14.

[0115] Of course, the third contact end 51 and the fourth contact end 52 may also be made of shape memory alloy, which will not be described in detail herein.

[0116] Alternatively, if Figure 2 As shown, the battery cell 10 in the embodiment of the present application includes a battery cell body 15 and a shell 16 , and the shell 16 is disposed on the outside of the battery cell body 15 .

[0117] like Figure 2As shown, the battery cell 10 in the embodiment of the present application includes a battery cell body 15 and a shell 16. The shell 16 is disposed outside the battery cell body 15, and the battery cell body 15 is encapsulated by the shell 16 to protect the internal structure of the battery cell body 15.

[0118] It should be noted that the housing 16 in the embodiment of the present application can be made of metal material, for example, the housing 16 can be made of aluminum. The housing 16 can also be made of plastic material, for example, the housing 16 can be made of polyethylene. Of course, in the embodiment of the present application, there are no excessive restrictions on the specific material of the housing 16, and in actual applications, technicians can choose according to needs.

[0119] like Figure 2 and Figure 3 As shown, a diaphragm 17 is also disposed in the battery cell body 15. The diaphragm 17 is a specially formed polymer film having a microporous structure, and ions can freely pass through the film.

[0120] The present application discloses a battery cell and a battery system, wherein the battery cell comprises a first pole ear; a first pole piece, through which an electrode can be led out; a first switch element, wherein within a first temperature range, the first switch element has a first form, and the first pole ear and the first pole piece are conductively connected; within a second temperature range, the first switch element has a second form, and the first pole ear and the first pole piece are non-conductively connected.

[0121] The battery cell disclosed in the present application includes a first pole ear, a first pole piece and a first switch, wherein the first pole piece leads out an electrode through the first pole ear, and within a first temperature range, the first switch has a first form so that the first pole ear and the first pole piece are conductively connected, and within a second temperature range, the first switch has a second form so that the first pole ear and the first pole piece are non-conductively connected. Through the above arrangement, the first pole ear and the first pole piece can be switched between conductive connection and non-conductive connection to protect the battery cell.

[0122] Furthermore, the first switch can be switched between the first state and the second state, so that the first pole piece and the first pole tab are conductively connected or the first pole piece and the first pole tab are non-conductively connected. In other words, the first switch can be used repeatedly, which helps to reduce the inconvenience of using and maintaining the battery cell and improve the user experience.

[0123] The embodiment of the present application further discloses a battery system, which includes an electrical device 40 and the battery cell 10 described in the above embodiment, wherein the electrical device 40 is electrically connected to the first electrode tab 12 .

[0124] like Figure 1As shown, the present application discloses a battery system, which includes the battery cell 10 and the electric device 40 described in the above embodiment. One end of the electric device 40 is electrically connected to the first pole ear 12 of the battery cell 10, and the other end of the electric device 40 is electrically connected to the second pole ear 14 of the battery cell 10. The battery cell 10 and the electric device form a loop.

[0125] It should be noted that the battery cell 10 included in the battery system disclosed in the embodiment of the present application has the same structure as the battery cell 10 described in the above embodiment, and its beneficial effects are also the same or similar, which will not be described in detail here.

[0126] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0127] Although the optional embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including optional embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.

[0128] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity from another entity, and do not necessarily require or imply any such actual relationship or order between these entities. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that an article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such article or terminal device. In the absence of further restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the article or terminal device including the elements.

[0129] The technical solution provided by the present invention is introduced in detail above. Specific examples are used in this article to illustrate the principle and implementation mode of the present invention. At the same time, for those skilled in the art, according to the principle and implementation mode of the present invention, there will be changes in the specific implementation mode and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A battery cell, characterized in that: include: First pole lug; A first pole piece, wherein the first pole piece may lead out an electrode through the first pole tab; A first switch element, within a first temperature range, wherein the first switch element has a first shape, and the first pole ear is conductively connected to the first pole piece; In a second temperature range, the first switch element has a second state, and the first pole ear and the first pole piece are non-conductively connected.

2. The battery cell according to claim 1, characterized in that: At least a portion of the first switch element is made of shape memory alloy.

3. The battery cell according to claim 2, characterized in that: The first switch element comprises: A first contact end, the first contact end is connected to the first electrode tab; a second contact end, the second contact end being connected to the first pole piece; The first contact end and / or the second contact end is made of shape memory alloy.

4. The battery cell according to claim 3, characterized in that: The resistance of the first contact end is R1=ρ1*L1 / S1, wherein the length of the first contact end is L1, the cross-sectional area of ​​the first contact end is S1, and the resistivity of the shape memory alloy in the first contact end is ρ1; And / or, the resistance of the second contact end is R2=ρ2*L2 / S2, wherein the length of the second contact end is L2, the cross-sectional area of ​​the second contact end is S2, and the resistivity of the shape memory alloy in the second contact end is ρ2.

5. The battery cell according to claim 3, characterized in that: The resistance of the first contact end is R3=c3*m3*△T3 / I3*t3, wherein the specific heat capacity of the shape memory alloy in the first contact end is c3, the mass of the first contact end is m3, the temperature value change of the first contact end is △T3, the short-circuit current flowing through the first contact end is I3, and the duration of the short-circuit current flowing through the first contact end is t3; And / or, the resistance of the second contact end is R4=c4*m4*△T4 / I4*t4, wherein the specific heat capacity of the shape memory alloy in the second contact end is c4, the mass of the second contact end is m4, the temperature value change of the second contact end is △T4, the short-circuit current flowing through the second contact end is I4, and the duration of the short-circuit current flowing through the second contact end is t4.

6. The battery cell according to claim 2, characterized in that: The specific heat capacity of the shape memory alloy in the first switch component is c5=R5*I52*t5 / m5*△T5, wherein the mass of the shape memory alloy in the first switch component is m5, the temperature value change of the shape memory alloy in the first switch component is △T5, the short-circuit current flowing through the shape memory alloy in the first switch component is I5, the time duration of the short-circuit current flowing through the shape memory alloy in the first switch component is t5, and the resistance of the shape memory alloy in the first switch component is R5.

7. The battery cell according to claim 2, characterized in that: The resistance R6 of the shape memory alloy in the first switch component is ρ6*L6 / S6, wherein the length of the shape memory alloy in the first switch component is L6, the cross-sectional area of ​​the shape memory alloy in the first switch component is S6, and the resistivity of the shape memory alloy in the first switch component is ρ6.

8. The battery cell according to claim 1, characterized in that: The first switch element has a first initial state. When a temperature value of the first switch element is less than or equal to a first preset temperature, the first switch element switches from the first initial state to the first state.

9. The battery cell according to claim 8, characterized in that: The first preset temperature is less than or equal to 45 degrees.

10. The battery cell according to claim 1, characterized in that: The first switch element has a first initial state. When a temperature value of the first switch element is greater than or equal to a second preset temperature, the first switch element switches from the first initial state to the second state.

11. The battery cell according to claim 10, characterized in that: The second preset temperature is greater than or equal to 150 degrees.

12. The battery cell according to any one of claims 1 to 11, characterized in that: The battery cell also includes: Second pole lug; A second pole piece, wherein the second pole piece may lead out an electrode through the second pole tab; An insulating layer is disposed between the first pole piece and the second pole piece.

13. The battery cell according to claim 12, characterized in that: A second switch element is connected between the second pole lug and the second pole piece; In a third temperature range, the second switch element has a third state, and the second pole ear is conductively connected to the second pole piece; In a fourth temperature range, the second switch element has a fourth state, and the second pole ear and the second pole piece are non-conductively connected.

14. The battery cell according to claim 13, characterized in that: At least a portion of the second switch element is made of shape memory alloy.

15. The battery cell according to claim 14, characterized in that: The second switch element comprises: a third contact terminal, the third contact terminal being connected to the second electrode tab; a fourth contact terminal connected to the second electrode piece; The third contact end and / or the fourth contact end are made of shape memory alloy.

16. A battery system, characterized in that: include: Electrical equipment; The battery cell according to any one of claims 1 to 15, wherein the electrical device is electrically connected to the first electrode tab.

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