Battery and electric equipment

Abstract

The invention discloses a battery and electric equipment, the battery comprises a battery cell and a safety assembly, the safety assembly comprises a resistor and a first temperature switch, the resistor comprises a first connecting part, a main body part and a second connecting part which are connected in sequence, and the first connecting part is electrically connected with a first electrode; the first temperature switch comprises a first conductive connecting piece, a first temperature control piece and a second conductive connecting piece, the first conductive connecting piece is electrically connected with the second connecting part, and the second conductive connecting piece is electrically connected with the second electrode; when the temperature of the first temperature control part is higher than a first preset temperature T1, the first temperature control part is in a first state, the first temperature switch is closed, and the battery is discharged; and when the temperature of the first temperature control piece is not greater than the first preset temperature T1, the first temperature control piece is in a second state, the first temperature switch is switched off, and the battery stops discharging. The battery can be discharged in a high-temperature environment through the first temperature switch and the resistor, and thermal runaway of the battery is avoided.

Description

Technical Field

[0001] The present application relates to the field of new energy technology, and in particular to a battery, and an electrical device equipped with the battery. Background Art

[0002] In the field of batteries, especially lithium-ion batteries, due to their high energy density and good charge and discharge cycle capacity, they have been widely used in mobile phones, laptops, electric vehicles and other fields. Lithium-ion batteries have been widely used in people's daily lives due to their high energy density and long cycle life. However, various battery safety issues frequently occur, making battery safety issues gradually valued, and more and more research is being conducted to improve battery safety.

[0003] The safety issues caused by battery thermal runaway are mainly because when the battery is under high load such as high power and high current, or when the battery is used in a relatively harsh environment such as high temperature, a large amount of heat is often generated inside the battery, and the battery temperature further rises. When the battery temperature rise cannot be suppressed or eliminated, the chemical system inside the battery will further deteriorate and the internal materials will be destroyed, resulting in thermal runaway, which in turn causes battery fires, explosions and other accidents. Summary of the invention

[0004] In view of this, the purpose of the present application is to provide a battery provided with a safety component, and an electrical device provided with the battery, which can discharge the battery in a high temperature environment through a first temperature switch and a resistor to avoid thermal runaway of the battery.

[0005] To achieve the above objectives, this application provides the following technical solutions:

[0006] A battery comprises a battery cell and a safety component, wherein the battery cell comprises a battery cell body and a first electrode and a second electrode extending from the battery cell body, wherein the first electrode and the second electrode have opposite polarities;

[0007] The safety component comprises a resistor and a first temperature switch, wherein:

[0008] The resistor comprises a first connecting portion, a main body portion and a second connecting portion which are connected in sequence, wherein the first connecting portion is electrically connected to the first electrode;

[0009] The first temperature switch comprises a first conductive connection member, a first temperature control member, and a second conductive connection member, wherein the first conductive connection member is electrically connected to the second connection portion, and the second conductive connection member is electrically connected to the second electrode;

[0010] When the temperature of the first temperature control component is greater than the first preset temperature T1, the first temperature control component is in a first state, and the first conductive connecting member and the second conductive connecting member are electrically connected through the first temperature control component;

[0011] When the temperature of the first temperature control component is not greater than the first preset temperature T1, the first temperature control component is in the second state, the first temperature control component is disconnected from the first conductive connector, and / or the first temperature control component is disconnected from the second conductive connector.

[0012] Optionally, in the above battery, the safety component further includes a second temperature switch:

[0013] The second temperature switch is connected in series with the first temperature switch, and the second temperature switch is further provided with a second temperature control component:

[0014] When the temperature of the second temperature control component is greater than the second preset temperature T4, the second temperature control component is in a third state, and the second temperature switch is controlled to be disconnected;

[0015] When the temperature of the second temperature control component is not greater than the second preset temperature T4, the second temperature control component is in a fourth state, and the second temperature switch is controlled to be closed;

[0016] T1<T4.

[0017] Optionally, in the above-mentioned battery, the first temperature control device includes any one or more combinations of bimetallic strips, trimetallic strips, and shape memory alloys; and / or, the second temperature control device includes any one or more combinations of bimetallic strips, trimetallic strips, or shape memory alloys.

[0018] Optionally, in the above battery, at least one of the first connecting portion and the second connecting portion and the main body are an integrally formed structural member made of the same material; and / or,

[0019] At least one of the first connection part and the second connection part is an external lead connected to the main body by welding or bonding or by a fastener; and / or,

[0020] The first connecting portion, the main body portion and the second connecting portion are stacked to form the resistor of a multi-layer structure; and / or,

[0021] The first temperature control component is integrally formed with the first conductive connector; or,

[0022] The first temperature control component and the second conductive connecting component are integrally formed.

[0023] Optionally, in the above battery, the main body is a polygonal panel structure, that is, a plate-like structure; and / or a hollow structure in the shape of a hole or a groove is provided on the surface of the main body.

[0024] Optionally, in the above battery, an insulating member is disposed in the hollow structure.

[0025] Optionally, in the above battery, the main body includes a first groove and a second groove arranged at intervals, and the main body includes a first side edge and a second side edge arranged oppositely;

[0026] The first groove extends from the first side toward the second side, and the distance between the inner wall surface of the first groove and the second side is greater than zero;

[0027] The second groove extends from the second side edge toward the first side edge, and a distance between an inner wall surface of the second groove and the first side edge is greater than zero.

[0028] Optionally, in the above battery, the first temperature switch further comprises a shell, and a containing cavity is provided inside the shell;

[0029] The first conductive connecting member is a sheet-like plate, and its two ends are respectively a first contact end and a first connecting end, the first contact end is located in the accommodating cavity, and the first connecting end extends to the outside of the housing and is electrically connected to the second connecting portion;

[0030] The second conductive connecting member is a sheet-shaped plate, and its two ends are respectively a second contact end and a second connection end, the second contact end is located in the accommodating cavity, the second connection end extends to the outside of the shell and is electrically connected to the second electrode, and the second contact end has a tendency to approach and abut against the first release end;

[0031] The first temperature control element is any one or more combinations of bimetallic strips, trimetallic strips, and shape memory alloys.

[0032] Optionally, in the above battery, the bimetallic strip is located between the first conductive connector and the second conductive connector, and when in a first state, the bimetallic strip bends toward the second conductive connector, and when in a second state, the bimetallic strip bends toward the first conductive connector; or,

[0033] The bimetal strip is located on a side of the second conductive connecting member facing away from the first conductive connecting member.

[0034] Optionally, in the above battery, the thickness of the main body is any value within the range of 1 μm to 2 mm; and / or,

[0035] The thickness of the first temperature control component is any value in the range of 0.02 to 2 mm; and / or,

[0036] The temperature curvature of the first temperature control unit is 1*10 -6 ~100*10 -6 Any value within the range of / ℃.

[0037] Optionally, in the above battery, the battery further comprises a shell, the battery cell body is located in the shell, and;

[0038] The main body is located on the outer surface of the battery body and is fixedly connected thereto; or, the main body is located on the inner wall of the shell and is fixedly connected thereto; or, the main body is located on the outer wall of the shell and is fixedly connected thereto;

[0039] and / or,

[0040] The first temperature switch is located at the top of the battery cell body and fixedly connected thereto; or, the first temperature switch is located inside the battery cell body; or, the first temperature switch is located at the top of the shell and fixedly connected thereto.

[0041] Optionally, in the above battery, the outer surface of the battery cell body includes a bottom surface, and a first side surface, a second side surface, a third side surface, and a fourth side surface arranged in sequence along the circumference of the bottom surface and connected end to end;

[0042] The main body is located on the first side surface or the third side surface; or, the main body covers the first side surface, the bottom surface and the third side surface.

[0043] Optionally, in the above battery, the main body includes at least one of a thin-sheet resistor, a resistor coating, an electroplated metal layer, and a chemically deposited metal layer.

[0044] Optionally, in the above battery, an insulating layer is provided between the main body and the outer surface of the battery cell body; wherein:

[0045] The insulating layer comprises at least one of a polymer and an inorganic ceramic; and / or,

[0046] The thermal conductivity of the material of the insulating layer is any value within the range of 0.01 to 0.9 W / (m·K); and / or,

[0047] The insulating layer comprises an adhesive; and / or,

[0048] The insulating layer includes a heat absorbing material.

[0049] Optionally, in the above battery, the ohmic impedance R of the resistor is 2 Any value in the range of 0.2Ω to 5Ω.

[0050] An electrical device comprises a body and the battery mentioned above.

[0051] It can be seen from the above technical solution that in the battery and electrical equipment provided by the present application, the safety component is formed by the first temperature switch and the resistor, and in the first temperature switch, since the first temperature control unit can present different structural states at different temperatures, it can timely sense the change of ambient temperature, and automatically control the first temperature switch to open in a high temperature environment, so that the battery can be controlled to discharge, and the heat is dissipated outward through the resistor, which is conducive to avoiding thermal runaway of the battery in a high temperature environment, making the battery safer. Moreover, when the ambient temperature drops to a safe range, the first temperature control unit automatically returns to its original state, so that the first temperature switch is automatically disconnected, and the discharge between the positive and negative electrodes of the battery stops. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0053] Figures 1 to 4 A schematic diagram of the structure of resistors of different shapes provided in the first specific embodiment of the present application.

[0054] Figure 5 and Figure 6 Schematic diagrams of the internal structure of the first temperature control switch provided in the first specific embodiment of the present application when it is in a closed state and an open state.

[0055] Figure 7 and Figure 8 Schematic diagrams of the internal structure of the first temperature control switch provided in the second specific embodiment of the present application when it is in a closed state and an open state.

[0056] Fig. 9 and Fig.10 Schematic diagrams of the internal structure of the first temperature control switch provided in the third specific embodiment of the present application when it is in a closed state and an open state.

[0057] Fig.11 This is a schematic diagram of the arrangement relationship of the battery cell body, insulation layer and resistor element provided in the first specific embodiment of the present application.

[0058] Fig.12 This is a front view of a battery provided in the first specific embodiment of the present application.

[0059] Fig.13 A side view of a battery provided in the first specific embodiment of the present application.

[0060] Fig.14A top view of a battery provided in the first specific embodiment of the present application.

[0061] Fig.15 A front view of a battery provided in the fourth specific embodiment of the present application.

[0062] Fig.16 A side view of a battery provided in accordance with the fourth specific embodiment of the present application.

[0063] Fig.17 A top view of a battery provided in the fourth specific embodiment of the present application.

[0064] Figures 18 to 21 They are schematic diagrams of structures of resistors of different shapes provided in other specific embodiments of the present application. DETAILED DESCRIPTION

[0065] The present application discloses a battery provided with a safety component, and an electrical device provided with the battery, which can discharge the battery in a high temperature environment through a first temperature switch and a resistor to avoid thermal runaway of the battery.

[0066] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0067] First specific embodiment

[0068] The battery provided in the first specific embodiment of the present application includes a battery cell and a safety component. Figure 1 The safety component includes at least one resistor 1 and at least one first temperature switch 2. The resistor 1 and the first temperature switch 2 are connected in series and are located between the first electrode 31 and the second electrode 32 of the battery body 3 to form a discharge circuit.

[0069] The battery cell includes a battery cell body 3, and a first electrode 31 and a second electrode 32 extending from the battery cell body 3, wherein the first electrode 31 and the second electrode 32 have opposite polarities (if the first electrode 31 is a positive electrode, the second electrode 32 is a negative electrode; if the first electrode 31 is a negative electrode, the second electrode 32 is a positive electrode);

[0070] The resistor 1 includes a first connection portion 11, a main body portion 13, and a second connection portion 12 which are connected in sequence, wherein the first connection portion 11 is electrically connected to the first electrode 31 of the battery cell;

[0071] The first temperature switch 2 includes a housing 26, a first pin 21 and a second pin 27 extending out of the housing 26, and a first temperature control unit 23 located in the housing 26. Among them: the portion of the first pin 21 located outside the housing 26 is used to electrically connect to the second connection portion 12 of the resistor 1, and the portion of the first pin 21 located inside the housing 26 is provided with a first conductive connector 22 (specifically, it can be an electrical contact sheet); the portion of the second pin 27 located outside the housing 26 is used to electrically connect to the second electrode 32 of the battery cell, and the portion of the second pin 27 located inside the housing 26 is provided with a second conductive connector 24 (specifically, it can be an electrical contact cantilever); the first temperature control unit 23 is used to control whether the first conductive connector 22 and the second conductive connector 24 are connected. (Or in other embodiments, it can also be: the portion of the second pin 27 located outside the housing 26 is electrically connected to the second connection portion 12 of the resistor 1, and the portion of the first pin 21 located outside the housing 26 is electrically connected to the second electrode 32 of the battery cell.)

[0072] During battery use:

[0073] See also Figure 6 When the temperature of the first temperature control unit 23 is not greater than the first preset temperature T1, the first temperature control unit 23 is in the second state; at this time, the first temperature control unit 23 supports the second conductive connecting member 24 so that the second conductive connecting member 24 is separated from the first conductive connecting member 22, thereby disconnecting the first pin 21 and the second pin 27, thereby disconnecting the first temperature switch 2, and disconnecting the circuit where the first temperature switch 2 and the resistor 1 are located;

[0074] See also Figure 5 When the temperature of the first temperature control unit 23 is greater than the first preset temperature T1, the first temperature control unit 23 is in the first state; at this time, the first temperature control unit 23 has no supporting force (or the supporting force is relatively small) on the second conductive connecting member 24, so that the second conductive connecting member 24 can be electrically connected to the first conductive connecting member 22 under the action of its own prestress, so that the first temperature switch 2 is closed, the first electrode 31 and the second electrode 32 of the battery cell are connected through the first temperature switch 2 and the resistor 1, and the battery is discharged through the resistor 1.

[0075] It can be seen that the first temperature switch 2 is a normally open temperature switch, and its trigger temperature is the first preset temperature T1. When the temperature of the environment where the first temperature switch 2 is located is lower than the trigger temperature, it remains in an open state, and when the temperature is higher than the trigger temperature, the switch is closed. In some embodiments, the value range of the first preset temperature T1 satisfies T2≤T1≤T3, T2 is the highest temperature at which the battery can work normally, and T3 is the lowest temperature at which the battery has thermal runaway.

[0076] In the first temperature switch 2, since the first temperature control unit 23 can present different structural states at different temperatures, it can timely sense the change of ambient temperature, and automatically control the first temperature switch 2 to open in a high temperature environment, so that the battery discharges, and dissipates heat to the outside through the resistor 1, which is conducive to avoiding thermal runaway of the battery in a high temperature environment, making the battery safer. Moreover, when the ambient temperature drops to a safe range, the first temperature control unit 23 automatically returns to its original state, so that the first temperature switch 2 is automatically disconnected, and the discharge between the positive and negative electrodes of the battery stops.

[0077] Furthermore, the safety component may also include a second temperature switch, which is specifically a normally closed temperature switch. When the temperature is lower than its trigger temperature, the second temperature switch remains closed; when the temperature is higher than the trigger temperature, the second temperature switch is opened.

[0078] Wherein: the triggering temperature of the second temperature switch is higher than the triggering temperature of the first temperature switch 2, the second temperature switch is connected in series with the first temperature switch 2, and the second temperature switch is also provided with a second temperature control unit: when the temperature of the second temperature control unit is greater than the second preset temperature T4, the second temperature control unit is in the third state, and controls the second temperature switch to be disconnected; when the temperature of the second temperature control unit is lower than the second preset temperature T4 (T4>T1), the second temperature control unit is in the fourth state, and controls the second temperature switch to be closed. In specific implementation, T3≤T4≤T3+T5 can be set, T3 is the lowest temperature at which the battery undergoes thermal runaway, and T5 can be any value in the range of 20℃ to 100℃. For example, T5 is any value among 21℃, 25℃, 30℃, 35℃, 40℃, 45℃, 50℃, 55℃, 60℃, 65℃, 70℃, 75℃, 80℃, 85℃, 90℃, and 95℃.

[0079] Thus, when the external environment temperature is too high, for example, when the temperature of the second temperature switch and the second temperature control unit inside it reaches or exceeds T4, the discharge circuit is disconnected through the second temperature switch, and the temperature of the resistor 1 is lowered before closing for discharge; when the external environment temperature is higher than T1 and lower than T4, the first temperature switch 2 and the second temperature switch are both in a closed state, and the discharge circuit remains on. Thus, intermittent discharge and heat release are formed, which can avoid thermal runaway of the battery due to excessive external environment temperature, and also avoid safety hazards caused by excessive temperature of the resistor 1.

[0080] In some embodiments, the second conductive connecting member 24 in the first temperature switch 2 is an electrical contact cantilever, which may adopt an elastically deformable conductive metal sheet structure; the first temperature control unit 23 in the first temperature switch 2 may be any one or more combinations of bimetallic sheets, trimetallic sheets, and shape memory alloys; similarly, the second temperature control unit in the above-mentioned second temperature switch may be any one or more combinations of bimetallic sheets, trimetallic sheets, and shape memory alloys. Alternatively, in other embodiments, the second conductive connector 24 and the first temperature control unit 23 of the electrical contact cantilever structure in the first temperature switch 2 may both be made of any one or more combinations of bimetallic strips, trimetallic strips or shape memory alloys: when the temperatures of the second conductive connector 24 and the first temperature control unit 23 are not greater than the first preset temperature T1, the states of the second conductive connector 24 and the first temperature control unit 23 enable the second conductive connector 24 to be kept away from the first conductive connector 22, thereby achieving disconnection between the first pin 21 and the second pin 27, that is, the first temperature switch 2 is disconnected; when the temperatures of the second conductive connector 24 and the first temperature control unit 23 are greater than the first preset temperature T1, the second conductive connector 24 and the first temperature control unit 23 are both deformed, so that the second conductive connector 24 is electrically connected to the first conductive connector 22, thereby closing the first temperature switch 2.

[0081] In a specific implementation, the thickness of the bimetallic strip can be any value in the range of 0.02 to 2 mm (for example, 0.1 mm, 0.5 mm, or 1 mm), and the thermal curvature of the bimetallic strip can be 1*10 -6 ~100*10 -6 Any value within the range of / ℃.

[0082] In addition, the first conductive connector 22 in the first temperature switch 2 , as well as the first pin 21 and the second pin 27 are all made of highly conductive materials, such as gold, copper, silver, aluminum, tin-plated copper, nickel-plated copper, stainless steel, etc.

[0083] See also Figure 5The housing 26 of the first temperature switch 2 is preferably an encapsulated housing. Wherein: a receiving cavity is arranged inside the shell 26; the part of the first conductive connector 22 located inside the shell 26 is an electrical contact sheet of a sheet-like plate structure, and the part located outside the shell 26 forms a first pin 21, that is, the two ends of the first conductive connector 22 are respectively a first contact end and a first connection end, the first contact end is located inside the receiving cavity, and the first connection end extends to the outside of the shell 26 to form the first pin 21, which is used to be electrically connected to the second connection portion 12 of the resistor 1; correspondingly, the part of the second conductive connector 24 located inside the shell 26 is an electrical contact cantilever of a sheet-like plate structure, and the part located outside the shell 26 forms a second pin 27, that is, the two ends of the second conductive connector 24 are respectively a second contact end and a second connection end, the second contact end is located inside the receiving cavity, and the second connection end extends to the outside of the shell 26 to form the second pin 27, which is used to be electrically connected to the second electrode 32 of the battery cell, and the second contact end has a tendency to approach and abut against the first contact end; the first temperature control unit 23 is a bimetallic strip, which can control whether the second contact end and the first contact end are in contact and connected.

[0084] For example, see Figure 5 and Figure 6 The first temperature control part 23 and the second conductive connecting part 24 in the first temperature switch 2 are both cantilever structures, and their movement amplitude can be any value in the range of 0.01 to 0.5 mm; the first temperature control part 23 is located between the first conductive connecting part 22 and the second conductive connecting part 24.

[0085] In some embodiments, the resistor 1 in the battery provided in the present application is an integrally formed structural member made of the same material, that is, the first connecting portion 11, the second connecting portion 12 and the main body 13 in the resistor 1 are integrally formed and connected.

[0086] Alternatively, in other embodiments, the first connection portion 11 and the second connection portion 12 in the resistor 1 may be external leads respectively welded or bonded to the main body 13 or connected via fasteners.

[0087] Alternatively, the first connecting portion 11, the main body portion 13 and the second connecting portion 12 are stacked, that is, the resistor 1 is Figure 4 For example, the resistor 1 is a heat-generating resistor of a thin sheet structure, and its material can be a metal material or a carbon material that can perform conductive and heat dissipation functions. Among them: the metal material is preferably stainless steel, aluminum, aluminum alloy, nickel, nickel alloy; the carbon material is preferably graphite, graphene, carbon nanotubes.

[0088] In some embodiments, the main body 13 of the resistor 1 is a polygonal panel structure, that is, the resistor 1 is Figure 1Alternatively, in other embodiments, the main body 13 of the resistor 1 may be a thin sheet structure with one or more slits, and the ohmic impedance of the resistor 1 may be adjusted by the shape and area of ​​the slits. In specific implementation, the slits on the main body 13 may be obtained by mechanical punching, laser cutting, chemical etching or electrochemical etching.

[0089] It should be noted here that the gap on the main body 13 refers to a hollow structure in the form of a channel or groove provided on the surface of the main body 13 of the resistor 1, wherein the channel can be a through hole, a countersunk hole or a hole of any other shape, and the shape of the channel or groove can be linear, arc-shaped or any other shape.

[0090] For example, the main body 13 is composed of Figure 2 The concave shape shown in , or Figure 3 , Fig.18 , Fig.19 , Fig. 20 Alternatively, in other embodiments, the holes or grooves on the surface of the main body 13 may be designed in other shapes, such as Fig.21 The hole or groove structure shown in FIG. 1 is distributed throughout the main body 13 .

[0091] Among them, Figure 3 as well as Figures 18 to 20 As shown in the figure, the main body 13 of the resistor 1 includes a first groove 1310 and a second groove 1320 arranged at intervals, and the main body 13 includes a first side 131 and a second side 132 arranged opposite to each other; the first groove 1310 extends from the first side 131 toward the second side 132, and the distance between the inner wall surface of the first groove 1310 and the second side 132 is greater than zero; the second groove 1320 extends from the second side 132 toward the first side 131, and the distance between the inner wall surface of the second groove 1320 and the first side 131 is greater than zero.

[0092] In specific implementation, the slit width of the above-mentioned channel or groove can be any value in the range of 10μm to 15mm, preferably any value in the range of 100μm to 1mm. For example, in some embodiments, the slit width in the above-mentioned hollow structure can be designed to be any value in 10μm, 20μm, 30μm, 40μm, 50μm, 60μm, 70μm, 80μm, 90μm, 100μm, 200μm, 300μm, 400μm, 500μm, 600μm, 700μm, 800μm, 900μm, 1mm, 2mm, 3mm, 4mm, 5mm, 10mm.

[0093] The ohmic impedance of the main body 13 can be increased by the above-mentioned hollow structure. It is easy to know that the more channels or grooves are set on the main body 13, the larger the hollow area, and the higher the impedance of the resistor 1. Reasonable setting of the gap width and length at each position in the hollow structure can make the heating power of the resistor 1 within the optimal range.

[0094] Furthermore, an insulating member is provided in the hollow structure, which may be affixed with insulating tape or coated with insulating adhesive in the hollow structure formed by the channel or groove of the resistor 1. In specific implementation, the material of the insulating member is preferably at least one of a polymer and a ceramic. The polymer is preferably PVDF (Polyvinylidene fluoride), PMMA (Polymethylmethacrylate, also known as acrylic or organic glass), polyimide, epoxy resin, and silica gel.

[0095] In some embodiments, the resistor 1 (especially the main body 13 ) may be any one of a thin-film resistor, a resistor coating, an electroplated metal layer, and a chemically deposited metal layer.

[0096] In some embodiments, the thickness of the main body 13 of the resistor 1 is d, 1μm≤d≤2mm, for example, d=2μm or 4μm or 5μm or 10μm or 15μm or 20μm or 25μm or 30μm or 40μm or 45μm or 50μm or 100μm or 200μm or 300μm or 400μm or 500μm or 600μm or 700μm or 800μm or 900μm or 1mm or 1.5mm. Preferably, d is any value in the range of 3μm to 20μm.

[0097] In some embodiments, the battery provided by the present application further includes a shell, and the battery cell body 3 is located in the shell. Moreover, the main body 13 in the resistor 1 is located inside or on the outer surface of the battery cell body 3 and is fixedly connected thereto; or, the main body 13 in the resistor 1 is located on the inner wall of the battery shell and is fixedly connected thereto; or, the main body 13 in the resistor 1 is located on the outer wall of the battery shell and is fixedly connected thereto.

[0098] In specific implementation, the main body 13 can be fixed to the outer surface of the battery body 3 by bonding, clamping, welding or connecting with fasteners, or the main body 13 can be fixed to the inner wall of the battery shell by bonding, clamping, welding or connecting with fasteners.

[0099] In addition, in some embodiments, the first temperature switch 2 can be arranged at the top of the battery cell body 3 (for example, outside the top seal) and fixedly connected thereto; or, the first temperature switch 2 is located inside the battery cell body 3; or, the first temperature switch 2 is located at the top of the battery casing and fixedly connected thereto.

[0100] For example, in some embodiments, the outer surface of the battery cell body 3 includes a bottom surface, and a first side surface, a second side surface, a third side surface, and a fourth side surface that are sequentially arranged and connected end to end along the circumference of the bottom surface; the first side surface and the third side surface are opposite to each other and have a relatively large area, and the first side surface and the second side surface are opposite to each other and have a relatively small area. In this case, the main body 13 can be attached to any side surface of the battery cell body 3, such as the first side surface (see Figure 12 to Figure 14 ) or the second side or the third side or the fourth side; or, the main body 13 may be attached to the first side and the bottom surface and the third side of the battery body 3 (see Figure 15 to Figure 16 ), or the main body 13 is attached to the second side surface, the bottom surface and the fourth side surface of the battery cell body 3.

[0101] See also Figure 12 to Figure 14 In some embodiments, the main body 13 is attached to the first side of the battery cell body 3, the first connecting portion 11 is located at the top of the battery cell body 3 and is connected in series with the first temperature switch 2 and the first electrode 31 in sequence, and the second connecting portion 12 is located at the top of the battery cell body 3 and is connected to the second electrode 32. At this time, the first connecting portion 11 and the second connecting portion 12 are both located at the top of the first side of the battery cell body 3 and extend toward the first electrode 31 and the second electrode 32 respectively. Among them, the first temperature switch 2 is set on any area on the top of the battery cell body 3 or on the top sealing edge 30 (see Fig.12 ), the two ends of the first temperature switch 2 are respectively welded to the first connection part 11 and the first electrode 31, and the end of the second connection part 12 away from the main body 13 is welded to the second electrode 32. The specific positions of the above welding points can be seen in Figure 12 to Figure 14 The welding area h in.

[0102] See also Figures 15 to 17 In some embodiments, the main body 13 is attached to the first side surface, the bottom surface and the third side surface of the battery cell body 3, the first connecting portion 11 is located at the top of the battery cell body 3 and is connected in series with the first temperature switch 2 and the first electrode 31 in sequence, and the second connecting portion 12 is located at the top of the battery cell body 3 and is connected to the second electrode 32. At this time, the first connecting portion 11 is located at the top of the first side surface of the battery cell body 3 and extends to a position close to the first electrode 31, and the second connecting portion 12 is located at the top of the third side surface of the battery cell body 3 and extends to the second electrode 32. Among them, the first temperature switch 2 is located at any area on the top of the battery cell body 3 or on the top sealing edge 30 (see Fig.15), the two ends of the first temperature switch 2 are respectively welded to the first connection portion 11 and the first electrode 31, and the end of the second connection portion 12 away from the third side surface of the battery cell body 3 is welded to the second electrode 32. The specific positions of the above welding points can be seen in Figures 15 to 17 The welding area h in.

[0103] See also Fig.11 In some embodiments, an insulating layer 4 is provided between the main body 13 and the outer surface of the battery cell body 3. The insulating layer 4 includes at least one of a polymer and an inorganic ceramic; the thermal conductivity of the insulating layer 4 is 0.01-0.9 W / (m·K), which can prevent the heat generated by the resistor 1 from heating the battery cell body, thereby further improving the safety performance.

[0104] Furthermore, in some embodiments, the insulating layer 4 may also have a bonding effect, and its material includes an adhesive, which can bond the battery body 3 and the thin-film resistor 1 together, and its bonding force is ≥0.1N / m, for example, the insulating layer 4 is an adhesive made of a polymer material.

[0105] Alternatively, in some embodiments, the insulating layer 4 may also include heat absorbing materials, such as phase change heat absorbing materials and chemical heat absorbing materials, so as to further improve the safety performance of the battery. It should be noted here that heat absorbing materials refer to materials that can effectively absorb heat and release heat, or in other words, heat absorbing materials refer to materials that can absorb heat when the temperature rises and release heat when the temperature drops. They usually have high specific heat capacity or latent heat characteristics, can effectively store and release heat within a certain temperature range, and can maintain stable performance in multiple heat absorption and heat release cycles, and are not easy to age or fail.

[0106] Specifically, when the temperature of the battery cell body 3 is high, the insulating layer 4 can absorb heat and transfer the heat to the main body 13 and the surrounding air, thereby playing a certain heat dissipation role for the battery cell body 3; when the temperature of the main body 13 is high, the insulating layer 4 can absorb the heat of the main body 13 to prevent the heat of the main body 13 from being directly transferred to the battery cell body 3, so that the insulating layer 4 can play a certain heat insulation role between the main body 13 and the battery cell body 3, and prevent the main body 13 from heating the battery cell body 3. In specific implementation, the insulating layer 4 can be any heat-absorbing material such as paraffin, fatty acid, polyethylene glycol, polyethylene, polyethylene wax, polypropylene, etc., or the insulating layer 4 can also be any heat-absorbing thermal conductive adhesive such as epoxy resin-based, silicone-based, polyurethane-based, acrylic-based, etc.

[0107] In some embodiments, the DC internal resistance R of the battery body 3 tested at 25° C. in a fully charged state is 0 , the ohmic resistance R of the first temperature switch 2 1 , the ohmic impedance R of the thin-film resistor 12 The relationship between them satisfies: 2(R 0 +R 1 )≤R 2 ≤1000(R 0 +R 1 ), R1 is any value in the range of 1 to 100Ω, R 0 , R 1 , R 2 The unit of is mΩ. In some embodiments, the battery capacity is set to Q (unit: mAh), and the DC internal resistance DCIR of the battery tested at 25°C in a fully charged state is set to R 0 (unit: mΩ), the ohmic resistance of the first temperature switch 2 is set to R 1 (unit: mΩ), the ohmic impedance of the thin-film resistor 1 is set to R 2 (unit: mΩ), then R 2 The best relationship with Q satisfies: Q(R 0 +R 1 ) / 5000≤R 2 ≤5000(R 0 +R 1 ). For example, in some embodiments, R 2 Any value within the range of 0.2Ω to 5Ω. 2 If it is too small, it will easily lead to high heat generation in a short time, causing the battery to heat up quickly and fail. 2 If it is too large, the discharge in a short time will be insufficient and the purpose of reducing the battery energy cannot be achieved. The battery is still prone to failure at high temperatures.

[0108] It should be noted here that the above-mentioned battery provided in the embodiment of the present application can be but is not limited to a lithium ion battery, a lithium metal battery, a lead-acid battery, a nickel-hydrogen battery, a lithium sulfur battery, a lithium-air battery, a sodium ion battery, a solid-state battery, etc.

[0109] Second specific embodiment

[0110] like Figure 7 and Figure 8 As shown in the second specific embodiment, the first temperature control part 23 in the first temperature switch 2 is an arc-shaped structure with both ends being free ends, and is located between the second conductive connecting member 24 and the first conductive connecting member 22. Moreover, the contact area 231 of the first temperature control part 23 is located at the arc vertex in the middle area thereof, and the shape of the first temperature control part 23 changes with the temperature. For example:

[0111] When the ambient temperature is high and reaches the trigger temperature of the first temperature switch 2, the first temperature control unit 23 is in the first state (see Figure 7), the first temperature control part 23 is bent toward the side where the second conductive connecting part 24 is located, and the two ends of the first temperature control part 23 are away from the second conductive connecting part 24 and are located in the inner wall groove of the shell 26, so as to control the second conductive connecting part 24 to contact with the first conductive connecting part 22, and the first temperature switch 2 is closed;

[0112] When the ambient temperature is lower than the trigger temperature of the first temperature switch 2, the first temperature control unit 23 is in the second state (see Figure 8 ), the first temperature control unit 23 is bent toward the side where the first conductive connector 22 is located, and both ends of the first temperature control unit 23 are tilted and support the second conductive connector 24, thereby controlling the second conductive connector 24 to move away from the first conductive connector 22, and the first temperature switch 2 is disconnected.

[0113] Third specific embodiment

[0114] like Fig. 9 and Fig.10 As shown in the third specific embodiment, the first temperature control part 23 in the first temperature switch 2 is an arc-shaped structure, and is located on the side of the second conductive connecting part 24 away from the first conductive connecting part 22. Moreover, the abutment area 231 of the first temperature control part 23 is located at the end, and the bending degree of the first temperature control part 23 changes with the temperature. For example:

[0115] When the ambient temperature is high and reaches the trigger temperature of the first temperature switch 2, the first temperature control unit 23 is in the first state (see Fig. 9 ), the first temperature control part 23 is bent to a greater extent, thereby squeezing the second conductive connecting part 24 to contact the first conductive connecting part 22, and the first temperature switch 2 is in a closed state;

[0116] When the ambient temperature is lower than the trigger temperature of the first temperature switch 2, the first temperature control unit 23 is in the second state (see Fig.10 ), the bending degree of the first temperature control part 23 becomes smaller, and its abutment area 231 moves slightly away from the second conductive connecting member 24, so that the second conductive connecting member 24 moves away from the first conductive connecting member 22 under the action of its own elastic restoring force. At this time, the first temperature switch 2 is in the disconnected state.

[0117] In summary, an embodiment of the present application further provides an electrical device, which includes a body and the battery described in any of the embodiments above.

[0118] In the specific implementation, lithium cobalt oxide can be selected as the positive electrode material of the lithium battery, graphite negative electrode material can be selected as the negative electrode material of the lithium battery, the battery core structure adopts a winding structure, and the outer packaging adopts a conventional aluminum-plastic film outer packaging to prepare lithium-ion battery samples for testing. The following is a comparative analysis of some specific embodiments and comparative examples in the test process as examples.

[0119]

[0120]

[0121]

[0122] Examples 1 to 13

[0123] In embodiments 1 to 13, a battery is provided, respectively, wherein the safety component described above is arranged between the positive and negative electrodes, that is, the first temperature switch 2 and the resistor 1 described above are arranged between the positive and negative ears of the battery body 3 of each battery. Among them, the battery body 3 in embodiments 1 to 13 is exactly the same, the first temperature switch 2 is exactly the same, and a 10μm thick metal stainless steel foil is used as the resistor 1 of the thin sheet structure. Among them, the first connecting portion 11 of the resistor 1 is connected to the positive ear of the battery, the second connecting portion 12 is connected to the first temperature switch 2, and the first temperature switch 2 is connected to the negative ear of the battery. The first temperature switch 2 is a normally open temperature switch provided with the first temperature control unit 23 as described above, and its triggering temperature is 85°C; in the resistor 1, a gap with a width of 0.5mm is engraved on the stainless steel foil by laser, so that the ohmic impedance between the two lead ends of the metal aluminum foil (that is, the first connecting portion 11 and the second connecting portion 12 in the resistor 1) is a preset value.

[0124] The only difference between Examples 1 to 13 is the ohmic impedance value of the resistor 1. The ohmic impedance values ​​of the resistor 1 in Examples 1 to 13 are 5.2Ω, 5.0Ω, 2.0Ω, 1.8Ω, 1.6Ω, 1.4Ω, 1.2Ω, 1.0Ω, 0.8Ω, 0.6Ω, 0.4Ω, 0.2Ω, and 0.1Ω, respectively.

[0125] From the test results in the above table, it can be seen that a larger or smaller ohmic impedance value of the resistor 1 will reduce the pass rate of the battery during the hot box safety test, and the optimal range is 0.2Ω

[0126] ~5.0Ω.

[0127] Examples 14 to 16

[0128] Compared with the above-mentioned embodiment 10, the difference between embodiments 14 to 16 is only that the triggering temperature of the first temperature switch 2 is different. Among them, the triggering temperatures of the first temperature switch 2 in embodiments 14 to 16 are: 75°C, 95°C, and 105°C respectively.

[0129] It can be seen from the test results in the above table that the lower the trigger temperature of the first temperature switch 2, the higher the pass rate of the battery in the hot box safety test. In order to enable the battery to adapt to a higher temperature environment as much as possible, in specific implementation, the optimal range of the trigger temperature of the first temperature switch 2 is set at 75°C to 85°C. In some cases, such as when the ambient temperature is not higher than 130°C, the trigger temperature of the first temperature switch 2 can also be set to any value within the range of 85°C to 105°C.

[0130] Comparative Example 1

[0131] Compared with the above-mentioned embodiments 1 to 16, the difference of comparative example 1 is that the battery does not include the safety component described above, that is, the first temperature switch 2 and the resistor 1 are not arranged between the positive and negative tabs of the battery cell.

[0132] It can be seen from the test results in the above table that the provision of the safety component consisting of the temperature switch and the resistor 1 between the positive and negative tabs of the battery cell can effectively improve the pass rate of the hot box safety test of the battery.

[0133] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0134] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments and the technical contents associated with the differences. The same or similar parts between the various embodiments can be referenced to each other.

[0135] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A battery, characterized in that: The invention comprises a battery cell and a safety component, wherein the battery cell comprises a battery cell body (3) and a first electrode (31) and a second electrode (32) extending from the battery cell body (3), wherein the polarities of the first electrode (31) and the second electrode (32) are opposite; The safety component comprises a resistor (1) and a first temperature switch (2), wherein: The resistor (1) comprises a first connecting portion (11), a main body portion (13) and a second connecting portion (12) which are connected in sequence, and the first connecting portion (11) is electrically connected to the first electrode (31); The first temperature switch (2) comprises a first conductive connection member (22), a first temperature control member (23) and a second conductive connection member (24), wherein the first conductive connection member (22) is electrically connected to the second connection portion (12), and the second conductive connection member (24) is electrically connected to the second electrode (32); When the temperature of the first temperature control unit (23) is greater than a first preset temperature T1, the first temperature control unit (23) is in a first state, and the first conductive connecting member (22) and the second conductive connecting member (24) are electrically connected via the first temperature control unit (23); When the temperature of the first temperature control unit (23) is not greater than the first preset temperature T1, the first temperature control unit (23) is in a second state, the first temperature control unit (23) is disconnected from the first conductive connecting member (22), and / or the first temperature control unit (23) is disconnected from the second conductive connecting member (24).

2. The battery according to claim 1, characterized in that The safety component also includes a second temperature switch: The second temperature switch is connected in series with the first temperature switch (2), and the second temperature switch is also provided with a second temperature control unit: When the temperature of the second temperature control component is greater than the second preset temperature T4, the second temperature control component is in a third state, and the second temperature switch is controlled to be disconnected; When the temperature of the second temperature control component is not greater than the second preset temperature T4, the second temperature control component is in a fourth state, and the second temperature switch is controlled to be closed; T1<T4.

3. The battery according to claim 1, characterized in that At least one of the first connecting portion (11) and the second connecting portion (12) and the main body (13) is an integrally formed structural component made of the same material; and / or, At least one of the first connection part (11) and the second connection part (12) is an external lead that is welded or bonded to the main body part (13) or connected via a fastener; and / or, The first connecting portion (11), the main body portion (13) and the second connecting portion (12) are stacked to form the resistor (1) with a multilayer structure; and / or The first temperature control component (23) and the first conductive connecting component (22) are integrally formed; or the first temperature control component (23) and the second conductive connecting component (24) are integrally formed.

4. The battery according to claim 1, characterized in that The main body (13) is a plate-like structure; and / or, The surface of the main body (13) is provided with a hollow structure in the shape of a channel or a groove.

5. The battery according to claim 4, characterized in that An insulating member is arranged in the hollow structure.

6. The battery according to claim 4, characterized in that The main body (13) comprises a first side edge (131) and a second side edge (132) arranged opposite to each other, and a first groove (1310) and a second groove (1320) arranged at intervals; The first groove (1310) extends from the first side edge (131) toward the second side edge (132), and a distance between an inner wall surface of the first groove (1310) and the second side edge (132) is greater than zero; The second groove (1320) extends from the second side edge (132) toward the first side edge (131), and a distance between an inner wall surface of the second groove (1320) and the first side edge (131) is greater than zero.

7. The battery according to claim 2, characterized in that The first temperature switch (2) further comprises a housing (26), wherein a receiving cavity is provided inside the housing (26); The first conductive connecting member (22) is a sheet-like plate, and its two ends are respectively a first contact end and a first connecting end, the first contact end is located in the accommodating cavity, and the first connecting end extends to the outside of the shell (26) and is electrically connected to the second connecting portion (12); The second conductive connecting member (24) is a sheet-like plate, and its two ends are respectively a second contact end and a second connection end, the second contact end is located in the accommodating cavity, the second connection end extends to the outside of the shell (26) and is electrically connected to the second electrode (32), and the second contact end has a tendency to approach and abut against the first contact end; The first temperature control unit (23) comprises any one or more combinations of bimetallic strips, trimetallic strips, and shape memory alloys; and / or the second temperature control unit comprises any one or more combinations of bimetallic strips, trimetallic strips, and shape memory alloys.

8. The battery according to any one of claims 1 to 7, characterized in that: The thickness of the main body (13) is any value in the range of 1 μm to 2 mm; and / or, The thickness of the first temperature control element (23) is any value in the range of 0.02 to 2 mm; and / or, The temperature curvature of the first temperature control unit (23) is 1*10 -6 ~100*10 -6 / any value within the range of ℃; and / or, The ohmic impedance R2 of the resistor (1) is any value in the range of 0.2Ω to 5Ω.

9. The battery according to claim 1, characterized in that The battery further comprises a shell, the battery cell body (3) is located inside the shell, and: The main body (13) is located on the outer surface of the battery body (3) and is fixedly connected thereto; or, the main body (13) is located on the inner wall of the shell and is fixedly connected thereto; or, the main body (13) is located on the outer wall of the shell and is fixedly connected thereto; and / or, The first temperature switch (2) is located at the top of the battery cell body (3) and is fixedly connected thereto; or, the first temperature switch (2) is located inside the battery cell body (3); or, the first temperature switch (2) is located at the top of the outer shell and is fixedly connected thereto.

10. The battery according to claim 9, characterized in that The outer surface of the battery cell body (3) comprises a bottom surface, and a first side surface, a second side surface, a third side surface, and a fourth side surface which are sequentially arranged along the circumference of the bottom surface and connected end to end; The main body (13) is located on the first side surface or the third side surface; or, the main body (13) covers the first side surface, the bottom surface and the third side surface.

11. The battery according to claim 1, characterized in that The main body (13) comprises at least one of a thin-sheet resistor, a resistor coating, an electroplated metal layer, and a chemically deposited metal layer; and / or, An insulating layer (4) is provided between the main body (13) and the outer surface of the battery cell body (3); wherein: The insulating layer (4) comprises at least one of a polymer and an inorganic ceramic; and / or, The thermal conductivity of the material of the insulating layer (4) is any value within the range of 0.01 to 0.9 W / (m·K); and / or, The insulating layer (4) comprises an adhesive; and / or, The insulating layer (4) comprises a heat absorbing material.

12. An electrical device, comprising a body, characterized in that: And the battery according to any one of claims 1 to 11.

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