Battery

Abstract

The utility model provides a battery which comprises a battery cell, a first tab and a second tab, the first tab and the second tab are arranged on the battery cell, the first tab and the second tab are connected through a connecting branch, and an on-off piece for controlling on-off of the connecting branch is arranged on the connecting branch. The on-off piece is arranged on the connecting branch between the first tab and the second tab of the battery cell, can control the on-off of the connecting branch, and can reduce the voltage and capacity of the battery by controlling the connection of the connecting branch, so that further deterioration of the battery caused by temperature rise of the battery is avoided, thermal runaway of the battery is avoided, and the service life of the battery is prolonged. And the use safety of the battery is improved. Moreover, after the voltage of the battery is reduced, the connection branch can be controlled to be disconnected through the on-off piece, so that the battery can work and be used normally.

Description

Technical Field

[0001] This application relates to the field of battery technology, specifically to a battery. Background Technology

[0002] In the battery field, especially lithium-ion batteries, due to their high energy density and good charge-discharge cycle life, they have been widely used in mobile phones, laptops, electric vehicles, and other fields. While lithium-ion batteries are widely used in daily life due to their high energy density and long cycle life, frequent battery safety issues have led to increasing attention to battery safety, resulting in more and more research into improving battery safety.

[0003] Safety issues caused by battery thermal runaway are mainly due to the fact that when a battery is used under high loads such as high power and high current, or in harsh environments such as high temperature, a large amount of heat is often generated inside the battery. The battery temperature rises further, and when the temperature rise cannot be suppressed or eliminated, the internal chemical system of the battery will deteriorate further, the internal materials will be damaged, and thermal runaway will occur, which will lead to accidents such as battery fire and explosion. Utility Model Content

[0004] In view of this, this application provides a battery that solves the problem of further battery deterioration and thermal runaway caused by continuous temperature rise when the battery is used under high loads such as high power and high current or in harsh environments such as high temperature. This application also provides a battery control method applicable to the above-mentioned battery.

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

[0006] A battery includes a cell and a first tab and a second tab disposed on the cell, wherein:

[0007] The first electrode and the second electrode are connected by a connecting branch, and a switching element for controlling the connection branch is provided on the connecting branch.

[0008] Optionally, the switching element includes a normally open temperature switch and a normally closed temperature switch connected in series, wherein:

[0009] The normally open temperature switch closes when the temperature is at the first temperature T1, the normally closed temperature switch opens when the temperature is at the second temperature T2, and the normally closed temperature switch closes when the temperature is at the third temperature T3, wherein T1, T2 and T3 satisfy: T2 > T3 > T1.

[0010] Optional,

[0011] T1 satisfies: 70℃≤T1≤90℃; and / or,

[0012] T2 satisfies: 130℃≤T2≤180℃; and / or,

[0013] T3 satisfies: 100℃≤T3≤120℃.

[0014] Optionally, the normally open temperature switch is disconnected when the temperature is at a fourth temperature T4, wherein T4 satisfies: T4≤50℃.

[0015] Optionally, the resistance of the normally open temperature switch in the closed state is R1, and the resistance of the normally closed temperature switch in the closed state is R2, wherein R1 and R2 satisfy the following condition: 0.1mΩ≤R1+R2≤1Ω, preferably, 1mΩ≤R1+R2≤100mΩ.

[0016] Optionally, the resistance of the normally open temperature switch in the closed state is R1, and the resistance of the normally closed temperature switch in the closed state is R2, wherein R1 and R2 satisfy the following condition: R1≤5*R2, preferably, R1≤2*R2.

[0017] Optionally, the normally open temperature switch includes a first base disposed within a first housing, a first insulating member, a first moving contact disposed on the first base, and a first stationary contact disposed on the first insulating member, wherein a first moving block is disposed at one end of the first moving contact near the first stationary contact.

[0018] Optionally, the normally closed temperature switch includes a second base disposed within the second housing, a second insulating member, a second moving contact disposed on the second base, and a second stationary contact disposed on the second insulating member, wherein a second moving block is disposed at one end of the second moving contact near the second stationary contact.

[0019] Optionally, the first housing and the second housing are the same housing.

[0020] Optionally, the battery cell is a laminated battery cell or a wound battery cell.

[0021] Optionally, the battery includes a plurality of first tabs and second tabs that are electrically connected in sequence, and the connection branch is disposed between the first tab located at one side end and the second tab located at the other side end.

[0022] The battery provided in this application incorporates a switching element on the connection branch between the first and second tabs of the battery cell. This switching element controls the connection branch's continuity, thereby reducing the battery's voltage and capacity. This prevents further battery deterioration due to overheating, avoids thermal runaway, and improves battery safety during use. Furthermore, after the battery voltage decreases, the switching element can be used to disconnect the connection branch, allowing the battery to operate normally and be used. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the battery structure under the first embodiment provided in this example;

[0025] Figure 2 This is a schematic diagram of the battery structure under the second embodiment;

[0026] Figure 3 This is a schematic diagram of the battery structure under the third embodiment;

[0027] Figure 4 This is a schematic diagram of the battery structure under the fourth embodiment;

[0028] Figure 5 This is a schematic diagram of a normally open temperature switch;

[0029] Figure 6 This is a schematic diagram of a normally closed temperature switch.

[0030] Figure 7 This is a schematic diagram of the circuit breaker.

[0031] exist Figures 1-7 middle:

[0032] 1-Battery cell, 2-First tab, 3-Second tab, 4-Connecting branch, 5-Connector;

[0033] 51 - Normally open temperature switch; 52 - Normally closed temperature switch;

[0034] 511-First housing, 512-First base, 513-First insulating element, 514-First moving contact piece, 515-First stationary contact piece, 516-First moving contact block, 521-Second housing, 522-Second base, 523-Second insulating element, 524-Second moving contact piece, 525-Second stationary contact piece, 526-Second moving contact block. Detailed Implementation

[0035] This application provides a battery.

[0036] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0037] like Figures 1 to 7 As shown in the figure, this application provides a battery, which can be a lithium-ion battery, a nickel-metal hydride battery, a lead-acid battery, etc. The battery mainly includes a cell 1 and a first tab 2 and a second tab 3 disposed on the cell 1, wherein the first tab 2 and the second tab 3 are connected by a connecting branch 4, and a switching element 5 for controlling the on and off of the connecting branch 4 is provided on the connecting branch 4.

[0038] In this embodiment, an optional implementation is provided. The switching element 5 consists of a temperature switch. Specifically, the temperature switch comprises a normally open temperature switch 51 and a normally closed temperature switch 52 connected in series. Under normal operating conditions (i.e., normal battery usage), the normally open temperature switch 51 is open, and the normally closed temperature switch 52 is closed. When the battery is used under high power, high current, or other high-load conditions, or in harsh environments such as high temperatures, the battery temperature will continuously rise. This temperature increase will cause the normally open temperature switch 51 to close. Since the normally closed temperature switch 52 is closed, the connection branch 4 between the first tab 2 and the second tab 3 is connected, allowing the battery to self-discharge. This reduces the battery voltage and capacity, preventing further battery deterioration due to overheating, avoiding thermal runaway, and improving battery safety during use. When the normally open temperature switch 51 is closed, the temperature of the connecting branch 4 will continue to rise. The normally closed temperature switch 52 will open after reaching a certain temperature, thus disconnecting the connecting branch 4 and preventing it from continuing to heat up and melting. At this time, the battery is working normally. When the temperature of the switching element 5 drops to a certain temperature, the normally closed temperature switch 52 will close again, thus protecting the battery again. The pulse discharge of the battery is achieved with the temperature change, which can better protect the battery and improve the safety of the battery during use.

[0039] In this embodiment, another optional implementation is also provided. The switching element 5 consists of a temperature sensor, a switch, and a control module. The temperature sensor is communicatively connected to the control module, and the switch is electrically connected to the control module. When the battery is in normal operating condition, the switch is in the open state. When the battery is used under high power, high current, or other high load conditions, or in harsh environments such as high temperature, the battery temperature will continuously rise. As the battery temperature rises, the temperature of the temperature sensor will also rise. The temperature sensor transmits temperature information to the control module. Based on the received temperature information, the control module controls the switch to close. At this time, the connection branch 4 between the first tab 2 and the second tab 3 is connected, and the battery self-discharges, thereby reducing the battery voltage and capacity, preventing further battery deterioration caused by overheating, avoiding thermal runaway, and improving battery safety during use. The control module receives the temperature information detected by the temperature sensor in real time. When the temperature rises significantly while the switch is closed, the control module controls the switch to open, disconnecting the connection branch 4 and preventing it from melting. When the temperature detected by the temperature sensor drops to a suitable temperature, the control module controls the switch to close again, thus protecting the battery once more. The pulse discharge achieved according to the temperature change can better protect the battery and improve the safety during battery use.

[0040] It should be noted that the connecting branch 4 is a conductive branch, used to realize the electrical connection between the first tab 2 and the second tab 3.

[0041] The battery with the above structure has a switching element 5 installed on the connecting branch 4 between the first tab 2 and the second tab 3 of the cell 1. The switching element 5 can control the opening and closing of the connecting branch 4. By controlling the connection of the connecting branch 4, the switching element 5 reduces the battery voltage and capacity, thereby preventing further battery deterioration caused by battery overheating, avoiding thermal runaway, and improving battery safety during use. Moreover, after the battery voltage drops, the switching element 5 can also control the connection branch 4 to disconnect, ensuring normal operation and use of the battery.

[0042] In some embodiments, the switching element 5 includes a normally open temperature switch 51 and a normally closed temperature switch 52 connected in series. The normally open temperature switch 51 is closed at a first temperature T1, and the normally closed temperature switch 52 is open at a second temperature T2. The normally closed temperature switch 52 is closed when the battery reaches a third temperature T3, where T1, T2, and T3 satisfy the condition: T2 > T3 > T1. Specifically, when the battery is operating normally, the normally open temperature switch 51 is open, and the normally closed temperature switch 52 is closed. However, when the battery is used under high power, high current, or other high-load conditions, or in harsh environments such as high temperatures, the battery temperature will continuously rise, and the temperature of the normally open temperature switch 51 will also rise. When the normally open temperature switch 51 reaches temperature T1, it is closed, while the normally closed temperature switch 52 is already closed. At this time, both switches connected in series in the connecting branch 4 are closed, and the connecting branch 4 is conductive, thus reducing the battery voltage and capacity. Since connecting branch 4 is in the conducting state, the temperature of normally closed temperature switch 52 will continue to rise. When the temperature of normally closed temperature switch 52 reaches temperature T2, it will be in the open state. At this time, connecting branch 4 is in the open state, and the number of normally closed temperature switches 52 on connecting branch 4 will decrease. When the temperature of normally closed temperature switch 52 drops to temperature T3, it will close again, and connecting branch 4 will be conducting again. During continuous battery operation, normally closed temperature switch 52 will repeat the above process, thereby achieving pulse discharge of the battery to ensure safety during battery use.

[0043] It should be noted that there is no limit to the number of normally open temperature switches 51 and normally closed temperature switches 52; one or more of each can be set.

[0044] Furthermore, by setting the normally open temperature switch 51 and normally closed temperature switch 52, the safety performance of the battery can be improved without affecting the chemical system. This method is applicable to various types of batteries and has little impact on the energy density of the battery.

[0045] It should also be noted that the connection method between the normally open temperature switch 51 and the normally closed temperature switch 52 and the first tab 2 and the second tab 3 is limited. For example, the electrical connection can be achieved by connecting wires, by soldering, resistance soldering, laser soldering, or by bonding with conductive adhesive.

[0046] It should also be noted that the normally open temperature switch 51, normally closed temperature switch 52 and connecting branch 4 can be located inside the battery, outside the battery, or connected between tabs of different polarities in the PACK or PCM protection board circuit.

[0047] In some embodiments, T1 satisfies: 70℃≤T1≤90℃. For example, T1 can be 70℃, 71℃, 72℃, 75℃, 80℃, 82℃, 85℃, 88℃, 89℃, 90℃, etc.

[0048] In some embodiments, T2 satisfies: 130℃≤T2≤180℃. For example, T2 can be 130℃, 131℃, 132℃, 135℃, 140℃, 150℃, 160℃, 170℃, 175℃, 177℃, 179℃, 180℃, etc.

[0049] In some embodiments, T3 satisfies: 100℃≤T3≤120℃. For example, T3 can be 100℃, 101℃, 102℃, 105℃, 110℃, 115℃, 117℃, 119℃, 120℃, etc.

[0050] By ensuring that T1, T2, and T3 are within the aforementioned range, it is possible to more flexibly control the battery discharge voltage and capacity, better prevent further battery deterioration caused by overheating, avoid battery thermal runaway, and improve battery safety during use.

[0051] In some embodiments, the normally open temperature switch 51 is disconnected at the fourth temperature T4. Based on the operation of the normally open temperature switch 51 and normally closed temperature switch 52, when the battery stops working, the temperatures of both normally open temperature switch 51 and normally closed temperature switch 52 will gradually decrease. When the temperature drops to T4, the normally open temperature switch 51, which is in the closed state, will open, thus disconnecting the connecting branch 4. This allows the normally open temperature switch 51 to open again when the battery is used next time, restoring the normally open temperature switch 51 and normally closed temperature switch 52 on the connecting branch 4 to their initial state. This ensures that the switching element 5 can still protect the battery from thermal runaway during subsequent battery use.

[0052] Where T4 satisfies: T4≤50℃. For example, T4 can be 50℃, 49℃, 45℃, 42℃, 40℃, 35℃, 30℃, 25℃, etc.

[0053] In some embodiments, the resistance of the normally open temperature switch 51 in the closed state is R1, and the resistance of the normally closed temperature switch 52 in the closed state is R2, wherein R1 and R2 satisfy the following conditions: 0.1mΩ≤R1+R2≤1Ω, R1≤5*R2. Here, ensuring that the resistances of the normally open temperature switch 51 and the normally closed temperature switch 52 satisfy the above relationship allows the normally open temperature switch 51 to close within a temperature range of 70°C to 90°C, the normally closed temperature switch 52 to open within a temperature range of 130°C to 180°C, and the normally closed temperature switch 52 to reclose when the temperature drops from the 130°C to 180°C range to the 100°C to 120°C range. This allows the normally open temperature switch 51 and the normally closed temperature switch 52 to more sensitively control the on / off state of the connecting branch 4, improving the convenience of controlling the temperature within the aforementioned range.

[0054] For example, the sum of the resistance values ​​of R1 and R2 can be 0.1mΩ, 0.2mΩ, 0.5mΩ, 1mΩ, 5mΩ, 10mΩ, 50mΩ, 100mΩ, 200mΩ, 500mΩ, 800mΩ, 900mΩ, 990mΩ, 998mΩ, 1Ω, etc. The relationship between R1 and R2 can be: R1 = R2, R1 = 1.5 * R2, R1 = 2 * R2, R1 = 3 * R2, R1 = 4 * R2, R1 = 4.5 * R2, R1 = 5 * R2.

[0055] Based on the above embodiments, further preferably, 1mΩ≤R1+R2≤100mΩ, and more preferably, R1≤2*R2. Ensuring that the resistance of the normally open temperature switch 51 and the normally closed temperature switch 52 satisfy the above relationship further improves the control effect on the on / off state of the connected branch, and further enhances the sensitivity of the normally open temperature switch 51 and the normally closed temperature switch 52 in controlling the on / off state of the connected branch 4.

[0056] It should be noted that, based on the internal resistance of different batteries, appropriate operating temperatures and resistances of the temperature switches are selected. When the resistance relationship between the normally open temperature switch 51 and the normally closed temperature switch 52 satisfies: R1≤2×R2, and R2≥1 / 2R1, the self-heating generated when the connecting branch 4 is connected can cause the temperature of the normally closed temperature switch 52 to reach its operating temperature, further enabling the subsequent intermittent occurrence of open-circuit and short-circuit, preventing the heat generated by the self-heating of the normally closed temperature switch from reaching its operating temperature for a prolonged period, at which point the battery heat has accumulated to its combustion temperature; and the normally open temperature switch 51 and the normally closed temperature switch 52... The resistance between switches 52 satisfies the following condition: 1mΩ≤R1+R2≤100mΩ. This resistance range of the temperature switch can ensure that the heat generated when the connecting branch 4 is connected does not concentrate on the battery, causing the battery temperature rise to be too large and causing failure, and that the heat generated on the temperature switch is too small, causing the normally closed temperature switch 52 to not reach the operating temperature and break the circuit, further accelerating the battery failure; on the other hand, it can also ensure that the heat generated during a short circuit does not concentrate excessively on the temperature switch, causing the normally closed temperature switch 52 to reach the operating temperature quickly, the short circuit time is very short, and it does not play a significant role in reducing the battery voltage drop.

[0057] In some embodiments, see Figure 5The normally open temperature switch 51 includes a first base 512 disposed in the first housing 511, a first insulating member 513, a first moving contact 514 disposed on the first base 512, and a first stationary contact 515 disposed on the first insulating member 513. A first moving contact block 516 is disposed at one end of the first moving contact 514 near the first stationary contact 515, and the first moving contact block 516 can contact or de-contact the first stationary contact 515 when the temperature changes. The first base 512 provides support for the first movable contact 514. A portion of the first movable contact 514 is disposed on the first base 512. The first insulating member 513 is disposed on the first housing 511. The first stationary contact 515 is disposed on the first insulating member 513. A first movable contact block 516 is disposed at one end of the first movable contact 514 near the first stationary contact 515. When the temperature changes, the first movable contact 514 can drive the first movable contact block 516 located at the end of the first movable contact 514 to move, so that the first movable contact block 516 contacts or de-contacts the first stationary contact 515, thereby realizing the connection or disconnection between the first movable contact 514 and the first stationary contact 515. Specifically, when the normally open temperature switch 51 rises to the first temperature, the first moving contact 514 drives the first moving contact block 516 to abut against the first stationary contact 515, thereby closing the normally open temperature switch 51. When the normally open temperature switch 51 drops to the fourth temperature, the first moving contact 514 drives the first moving contact block 516 away from the first stationary contact 515, disconnecting the connection between the first moving contact block 516 and the first stationary contact 515, thus opening the normally open temperature switch 51. In this way, the opening and closing of the normally open temperature switch 51 can be conveniently controlled by changing the temperature.

[0058] Please see Figure 6The normally closed temperature switch 52 includes a second base 522 disposed in the second housing 521, a second insulating member 523, a second moving contact 524 disposed on the second base 522, and a second stationary contact 525 disposed on the second insulating member 523. A second moving contact block 526 is disposed at one end of the second moving contact 524 near the second stationary contact 525, and the second moving contact block 526 can contact or de-contact the second stationary contact 525 when the temperature changes. The second base 522 provides support for the second movable contact 524. A portion of the second movable contact 524 is disposed on the second base 522. The second insulating member 523 is disposed on the second housing 521. The second stationary contact 525 is disposed on the second insulating member 523. The second movable contact 524 is provided with two movable contact blocks 526 near the two ends of the second stationary contact 525. When the temperature changes, the second movable contact 524 can drive the second movable contact blocks 526 located at the ends of the second movable contact 524 to move, so that the second movable contact blocks 526 contact or de-contact the second stationary contact 525, thereby realizing the connection or disconnection between the second movable contact 524 and the second stationary contact 525. Specifically, when the normally closed temperature switch 52 rises to the second temperature, the second moving contact 524 moves the second moving contact block 526 away from the second stationary contact 525, thereby opening the normally closed temperature switch 52. Conversely, when the normally closed temperature switch 52 drops to the third temperature, the second moving contact 524 moves the second moving contact block 526 closer to the second stationary contact 525, connecting the second moving contact block 526 and the second stationary contact 525, thus closing the normally closed temperature switch 52. This allows for convenient control of the normally closed temperature switch 52's opening and closing by adjusting the temperature.

[0059] Temperature switches can be categorized into enclosed and open types based on whether they have a housing. Both operate on the same principle. Open-type temperature switches, however, have a more sensitive bimetallic strip that dissipates heat faster than ambient temperatures, but their structural stability is more susceptible to external damage. The configuration of normally open temperature switch 51 and normally closed temperature switch 52 is also specified here; either enclosed or open-type temperature switches can be selected.

[0060] Based on the above embodiments, please refer to the following for further details. Figure 7 The first housing 511 and the second housing 521 are the same housing. That is to say, the normally open temperature switch 51 and the normally closed temperature switch 52 share a housing, which reduces the number of non-critical components, reduces the overall area occupied by the normally open temperature switch 51 and the normally closed temperature switch 52, makes the layout of the normally open temperature switch 51 and the normally closed temperature switch 52 more compact, and makes the overall battery structure simple and clear.

[0061] In addition, the first housing 511 and the second housing 521 can also be different housings.

[0062] In some embodiments, the battery cell 1 is a laminated battery cell or a wound battery cell. The laminated battery cell is formed by alternating layers of positive and negative electrode sheets, and a separator is disposed between adjacent positive and negative electrode sheets; the wound structure is formed by winding positive and negative electrode sheets, and a separator is disposed between adjacent positive and negative electrode sheets.

[0063] In addition, according to the shape, the battery cell 1 can also be an aluminum shell battery cell, a pouch battery cell, or a cylindrical battery cell, etc.; according to the positive electrode material, the battery cell can also be a lithium cobalt oxide battery cell, a ternary lithium battery cell, or a lithium iron phosphate battery cell, etc.

[0064] In some embodiments, the battery includes a plurality of first tabs 2 and second tabs 3 connected in sequence, and a connecting branch 4 is disposed between the first tab 2 located at one end and the second tab 3 located at the other end. Specifically, as shown in the figure... Figure 3 As shown, taking a battery consisting of two batteries as an example, the negative terminal of the first battery and the positive terminal of the second battery are connected by a wire. A connecting branch 4 is set between the positive terminal of the first battery and the negative terminal of the second battery, and the aforementioned switching element 5 is set on the connecting branch 4. Through the above arrangement, the safety of multiple batteries can be protected by setting a single switching element 5, thereby improving its safety performance. It also reduces the number of switching elements 5 required, making the overall layout simpler.

[0065] It should be noted that there is no limit to the number of batteries that can be connected; two or more can be set.

[0066] It should also be noted that battery shapes include, but are not limited to, cylindrical batteries, square batteries, pouch batteries, or other irregularly shaped batteries; battery systems include, but are not limited to, lithium metal batteries, lithium-ion batteries, lithium-sulfur batteries, lithium-air batteries, sodium metal batteries, sodium-ion batteries, aluminum batteries, magnesium batteries, zinc batteries, etc.

[0067] The following section presents furnace temperature test experiments conducted on different battery models, with the specific results as follows:

[0068] Example 1: A normally open temperature switch 51 with a closing resistance of 1mΩ and an operating temperature of 70℃ and a normally closed temperature switch 52 with a resistance of 1mΩ and an operating temperature of 140℃ are connected in series via leads or pins. The series-connected switches are then connected to the positive and negative terminals of a battery with an internal resistance of 5mΩ via soldering or laser soldering. The structure is as follows: Figure 1 As shown in the figure; then the manufactured battery was placed in a hotbox for furnace temperature testing at 132°C and 135°C. The test results are shown in Table 1.

[0069] Example 2: Replace the normally open temperature switch 51 with a closing resistance of 4mΩ and an operating temperature of 80℃; replace the normally closed temperature switch 52 with a resistance of 4mΩ and an operating temperature of 170℃, and the rest are the same as in Example 1;

[0070] Example 3: Replace the normally open temperature switch 51 with a closing resistance of 4mΩ and an operating temperature of 75℃; replace the normally closed temperature switch 52 with a resistance of 4mΩ and an operating temperature of 140℃; replace the battery with a battery with an internal resistance of 15mΩ, and the rest are the same as in Example 1.

[0071] Example 4: Replace the normally open temperature switch 51 with a closing resistance of 4mΩ and an operating temperature of 85℃; replace the normally closed temperature switch 52 with a resistance of 7mΩ and an operating temperature of 170℃; replace the battery with a battery with an internal resistance of 15mΩ, and the rest are the same as in Example 1.

[0072] Example 5: Replace the normally open temperature switch 51 with a closing resistance of 12mΩ and an operating temperature of 75℃; replace the normally closed temperature switch 52 with a resistance of 12mΩ and an operating temperature of 140℃; replace the battery with a battery with an internal resistance of 15mΩ; the rest are the same as in Example 1.

[0073] Example 6: Replace the normally open temperature switch 51 with a closing resistance of 4mΩ and an operating temperature of 75℃; replace the normally closed temperature switch 52 with a resistance of 4mΩ and an operating temperature of 140℃; replace the battery with a battery with an internal resistance of 30mΩ; the rest are the same as in Example 1.

[0074] Example 7: Replace the normally open temperature switch 51 with a closing resistance of 4mΩ and an operating temperature of 85℃; replace the normally closed temperature switch 52 with a resistance of 7mΩ and an operating temperature of 180℃; replace the battery with a battery with an internal resistance of 30mΩ; and the rest are the same as in Example 1.

[0075] Example 8: Replace the normally open temperature switch 51 with a closing resistance of 12mΩ and an operating temperature of 75℃; replace the normally closed temperature switch 52 with a resistance of 12mΩ and an operating temperature of 150℃; replace the battery with a battery with an internal resistance of 30mΩ; and the rest are the same as in Example 1.

[0076] Example 9: Replace the normally open temperature switch 51 with a closing resistance of 4mΩ and an operating temperature of 75℃; replace the normally closed temperature switch 52 with a resistance of 7mΩ and an operating temperature of 160℃; replace the battery with a battery with an internal resistance of 50mΩ; the rest are the same as in Example 1.

[0077] Example 10: Replace the normally open temperature switch 51 with a closing resistance of 12mΩ and an operating temperature of 75℃; replace the normally closed temperature switch 52 with a resistance of 7mΩ and an operating temperature of 170℃; replace the battery with a battery with an internal resistance of 50mΩ; and the rest are the same as in Example 1.

[0078] Example 11: Replace the normally open temperature switch 51 with a closing resistance of 40mΩ and an operating temperature of 70℃; replace the normally closed temperature switch 52 with a resistance of 60mΩ and an operating temperature of 160℃; replace the battery with a battery with an internal resistance of 50mΩ; and the rest are the same as in Example 1.

[0079] Comparative example: Batteries with different internal resistances (without any operation) were placed in a hotbox for furnace temperature tests at 132°C and 135°C. The specific parameters and test results are shown in Table 1.

[0080] Furnace temperature test method: Charge the battery to the upper voltage at a constant current and constant voltage of 0.5C, and cut off the current of 0.02C. Then, put the fully charged cell into the test chamber. The test chamber is heated at a temperature rise rate of (5±2)℃ / min. When the temperature inside the chamber reaches the target temperature, it is kept constant for 60 minutes. If the cell does not burn or explode after the test, the furnace temperature test at the target temperature is passed.

[0081] Table 1

[0082]

[0083]

[0084] As shown in Table 1, under the same battery internal resistance conditions, the sum of the resistances of the normally open temperature switch 51 and the normally closed temperature switch 52 is less than the battery internal resistance. Furthermore, the greater the difference between the operating temperature of the normally open temperature switch 51 and the operating temperature of the normally closed temperature switch 52 (the difference in operating temperature is at least greater than 40°C), the higher the battery safety performance.

[0085] The basic principles of this application have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this application are merely examples and not limitations, and should not be considered as essential features of each embodiment of this application. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the application to the necessity of employing the aforementioned specific details for implementation.

[0086] The block diagrams of devices, apparatuses, devices, and systems involved in this application are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, apparatuses, devices, and systems can be connected, arranged, and configured in any manner. Words such as “comprising,” “including,” “having,” etc., are open-ended terms meaning “including but not limited to,” and are used interchangeably with them. The terms “or” and “and” as used herein refer to the terms “and / or,” and are used interchangeably with them unless the context clearly indicates otherwise. The term “such as” as used herein refers to the phrase “such as but not limited to,” and is used interchangeably with it.

[0087] It should also be noted that in the apparatus, equipment, and methods of this application, the components or steps can be disassembled and / or recombined. These disassemblies and / or recombinations should be considered as equivalent solutions of this application.

[0088] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use this application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects without departing from the scope of this application. Therefore, this application is not intended to be limited to the aspects shown herein, but rather to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0089] It should be understood that the qualifiers “first,” “second,” “third,” “fourth,” “fifth,” and “sixth” used in the description of the embodiments of this application are only used to more clearly illustrate the technical solutions and are not intended to limit the scope of protection of this application.

[0090] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this application to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

Claims

1. A battery, characterized in that, Includes a battery cell and a first tab and a second tab disposed on the battery cell, wherein: The first electrode and the second electrode are connected by a connecting branch, and a switching element for controlling the opening and closing of the connecting branch is provided on the connecting branch; The switching element includes a temperature switch; and / or the switching element includes a temperature sensor, a switch, and a control module.

2. The battery according to claim 1, characterized in that, The temperature switch includes a normally open temperature switch and a normally closed temperature switch connected in series, wherein: The normally open temperature switch closes when the temperature is at the first temperature T1, the normally closed temperature switch opens when the temperature is at the second temperature T2, and the normally closed temperature switch closes when the temperature is at the third temperature T3, wherein T1, T2 and T3 satisfy: T2 > T3 > T1.

3. The battery according to claim 2, characterized in that, T1 satisfies: 70℃≤T1≤90℃; and / or, T2 satisfies: 130℃≤T2≤180℃; and / or, T3 satisfies: 100℃≤T3≤120℃.

4. The battery according to claim 2, characterized in that, The normally open temperature switch is disconnected when the temperature is at the fourth temperature T4, where T4 satisfies: T4≤50℃.

5. The battery according to claim 2, characterized in that, The resistance of the normally open temperature switch in the closed state is R1, and the resistance of the normally closed temperature switch in the closed state is R2, wherein R1 and R2 satisfy the following condition: 0.1mΩ≤R1+R2≤1Ω.

6. The battery according to claim 5, characterized in that, The following condition must be satisfied between R1 and R2: 1mΩ≤R1+R2≤100mΩ.

7. The battery according to claim 5, characterized in that, The resistance of the normally open temperature switch in the closed state is R1, and the resistance of the normally closed temperature switch in the closed state is R2, wherein R1 and R2 satisfy the following condition: R1≤5*R2.

8. The battery according to claim 7, characterized in that, R1 and R2 satisfy the condition: R1≤2*R2.

9. The battery according to claim 2, characterized in that, The normally open temperature switch includes a first base disposed within a first housing, a first insulating member, a first movable contact disposed on the first base, and a first stationary contact disposed on the first insulating member, wherein a first movable block is disposed at one end of the first movable contact near the first stationary contact.

10. The battery according to claim 2, characterized in that, The normally closed temperature switch includes a second base disposed within a second housing, a second insulating member, a second moving contact disposed on the second base, and a second stationary contact disposed on the second insulating member, wherein a second moving block is disposed at one end of the second moving contact near the second stationary contact.

11. The battery according to claim 9, characterized in that, The first housing and the second housing are the same housing.

12. The battery according to claim 1, characterized in that, The battery cell is a laminated battery cell or a wound battery cell.

13. The battery according to claim 1 or 2, characterized in that, The battery includes a plurality of first tabs and second tabs that are electrically connected in sequence, and the connection branch is disposed between the first tab located at one end and the second tab located at the other end.

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