battery

Abstract

This application provides a battery comprising a metal casing, the metal casing including a bottom shell and a cover plate, the bottom shell and the cover plate forming a receiving cavity; a battery cell, housed within the receiving cavity, the battery cell including a positive electrode plate and a negative electrode plate stacked thereon, the positive electrode plate including a positive current collector and a positive electrode tab extending from one side of the positive current collector; the negative electrode plate including a negative current collector and a negative electrode tab extending from one side of the negative current collector; a heating element disposed in the battery, the heating element being used to heat the battery; and a temperature sensor for detecting the temperature of the battery, the metal casing and the heating element connecting when the temperature of the battery is lower than a preset threshold. This application solves the problems of slow charging speed and easy lithium plating in batteries at low temperatures.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to batteries. Background Technology

[0002] Lithium-ion batteries are increasingly widely used in various applications. However, using lithium-ion batteries at lower temperatures can lead to several problems, including capacity decay, reduced charge and discharge efficiency, and even the potential deposition of metallic lithium at the negative electrode.

[0003] Currently, to improve battery performance in low-temperature environments, low-temperature heating strategies are employed. These strategies include DC current heating, AC current heating, pulsed current heating, liquid-based heating, and water channels that facilitate heat dissipation to evenly distribute heat within the battery pack, achieving a uniform temperature rise. However, none of these solutions effectively address the challenges of battery performance at low temperatures.

[0004] The preceding description is intended to provide general background information and does not necessarily constitute prior art. Utility Model Content

[0005] This application provides a battery that solves the problems of slow charging speed and easy lithium plating at low temperatures.

[0006] This application provides a battery, comprising:

[0007] The metal shell includes a bottom shell and a cover plate, which together form a receiving cavity.

[0008] A battery cell is housed within a housing cavity. The battery cell includes a positive electrode plate and a negative electrode plate. The positive electrode plate includes a positive current collector and a positive tab extending from one side of the positive current collector. The negative electrode plate includes a negative current collector and a negative tab extending from one side of the negative current collector.

[0009] The bottom shell includes a first sidewall and a through hole located on the first sidewall. A positive electrode connector is provided on the first sidewall. The positive electrode connector includes a positive electrode post and an insulating layer. The insulating layer is located on the positive electrode post and the first sidewall. The positive electrode post includes a positive electrode extension extending into the through hole. The positive electrode extension is connected to a positive electrode tab. The bottom shell is electrically connected to a negative electrode tab.

[0010] The heating element is electrically connected to the housing.

[0011] Temperature sensor used to detect battery temperature;

[0012] The control unit includes a heating control circuit and a charging control circuit; when the battery is connected to an external power source, and the battery temperature is lower than a preset threshold, the heating control circuit activates the heating element, the metal casing, and the negative electrode tab.

[0013] When the battery temperature exceeds a preset threshold, the charging control circuit controls the positive tab, the battery cell, and the negative tab.

[0014] Through the above-mentioned settings, namely the heating element, the heating control circuit is activated when the battery temperature is below a preset threshold, thereby heating the casing and increasing the overall temperature of the battery. This prevents the battery from operating at low temperatures, reducing battery wear and extending its lifespan. Furthermore, it ensures that the battery maintains good performance in low-temperature environments, allowing it to operate within a more stable temperature range and reducing safety hazards. In addition, the use of a temperature sensor enables real-time monitoring of the battery temperature and activation of the heating function when necessary, reducing the rate of battery degradation and improving the cycle life of the cell.

[0015] In some alternative embodiments, the heating element includes at least one heating tab disposed on the metal casing; and / or, along the thickness direction of the battery, the projection of one of the positive and negative tabs does not overlap with the projection of the heating element.

[0016] The above-mentioned technical solution has the following advantages or beneficial effects: The design of placing the heating tabs on the metal shell not only improves heating efficiency and system reliability, but also may reduce costs and simplify design. Furthermore, the projections of the positive or negative tabs and the heating element do not overlap, avoiding mutual interference.

[0017] In some alternative implementations, the distance between the heating tab and the positive tab is greater than or equal to 2 mm.

[0018] The above technical solution has the following advantages or beneficial effects: such a design prevents short circuits during charging and discharging.

[0019] In some alternative embodiments, the thickness of the heating tab is 0.06 mm to 0.2 mm; and / or,

[0020] The width of the heating tabs is 4mm-20mm.

[0021] The above technical solution has the following advantages or beneficial effects: If the thickness and width of the heating tab are too large, it will lead to an increase in material and processing costs, as well as an increase in overall weight. If the thickness and width of the heating tab are too small, it may be susceptible to physical damage, such as bending or breakage, affecting its normal service life. It will also increase the complexity of the manufacturing process, leading to higher production costs and potentially affecting production efficiency.

[0022] In some alternative embodiments, the heating element further includes at least one nickel sheet. The battery cell has a stacked structure, with the nickel sheet disposed within the stacked structure. The nickel sheet includes a body and at least one nickel sheet extension extending from one side of the body. An insulating layer is formed on two opposite side surfaces of the body. A lead-out is provided on the side wall of the bottom shell. The first end of the lead-out is connected to the nickel sheet extension, and the second end of the lead-out is connected to an external power source.

[0023] The above technical solution has the following advantages or beneficial effects: the addition of nickel sheets and their specific design layout not only improve the thermal management efficiency of the battery, but also enhance the performance stability and safety of the battery.

[0024] In some alternative embodiments, the internal resistance of the nickel sheet is 40Ω-200mΩ; and / or,

[0025] The width of the nickel sheet is 0.05mm-0.5mm.

[0026] The above technical solution has the following advantages or beneficial effects: by optimizing the internal resistance and width of the nickel sheet, heating and thermal management efficiency can be improved without significantly increasing energy consumption, thereby improving the efficiency of the entire battery system.

[0027] In some alternative implementations, the internal resistance of the nickel sheet is 50Ω-100mΩ.

[0028] The above technical solution has the following advantages or beneficial effects: by setting the internal resistance between 50Ω and 100mΩ, the current passing through the nickel sheet can be effectively controlled. This resistance range allows for limiting current flow when needed to prevent overheating, while also providing sufficient current for heating when required.

[0029] In some alternative implementations, a groove is formed on the bottom shell, and the groove is recessed into the metal shell in the direction of the bottom shell inward.

[0030] The above technical solution has the following advantages or beneficial effects: by designing grooves on the bottom metal shell, the length of the current path can be effectively increased, thereby increasing the internal resistance. This increased internal resistance allows the current to generate more heat when passing through, thus improving heating efficiency.

[0031] In some alternative implementations, the area S of the bottom metal shell and the area s of the groove satisfy the following relationship: s = a * S, 1 / 3 ≤ a ≤ 3 / 5; and / or,

[0032] The thickness H of the bottom metal shell and the depth h of the groove satisfy the following relationships: h = b * H, 1 / 3 ≤ b ≤ 2 / 3; and / or,

[0033] The width of the groove is 0.1um-100um.

[0034] In some alternative implementations,

[0035] The internal resistance of the metal casing is 10Ω-500mΩ; and / or,

[0036] The heating power of the metal casing is 2W-40W; and / or,

[0037] The thickness of the metal casing is 0.06mm-0.2mm; and / or,

[0038] The hardness of the metal casing is limited to 30 HRB-66 HRB; and / or,

[0039] The thermal conductivity of the metal shell is 15 W / (m·K)-100 W / (m·K).

[0040] The above technical solution has the following advantages or beneficial effects: The metal casing, as the battery's casing material, not only affects the battery's appearance and structure but also its internal performance. Because the entire metal casing is connected to the negative electrode, a high internal resistance in the metal casing will affect the transport of electrons and ions between the electrodes and the electrolyte, reducing the battery's output current capability. Conversely, a low internal resistance in the metal casing will result in lower heating efficiency.

[0041] In some alternative embodiments, the metal casing is one of a cold-rolled metal casing, a hot-rolled metal casing, a stainless metal casing, a galvanized metal casing, an aluminum alloy casing, and a titanium alloy casing; and / or,

[0042] The internal resistance of the metal casing is 20Ω-100mΩ.

[0043] The battery provided in this application embodiment includes: a metal casing, the metal casing including a bottom shell and a cover plate, the bottom shell and the cover plate forming a receiving cavity; a battery cell, housed in the receiving cavity, the battery cell including a positive electrode plate and a negative electrode plate, the positive electrode plate including a positive current collector and a positive electrode tab extending from one side of the positive current collector; the negative electrode plate including a negative current collector and a negative electrode tab extending from one side of the negative current collector; the bottom shell including a first sidewall and a through hole located on the first sidewall, the first sidewall being provided with a positive electrode connector, the positive electrode connector including a positive electrode post and an insulating layer, the insulating layer being located on the positive electrode post. On the first sidewall, the positive electrode post includes a positive electrode extension extending into a through hole, the positive electrode extension being connected to the positive electrode tab, and the bottom shell and the negative electrode tab being electrically connected; a heating element electrically connected to the shell; a temperature sensor for detecting the battery temperature; and a control unit, which includes a heating control circuit and a charging control circuit. When the battery is connected to an external power source, if the battery temperature is below a preset threshold, the heating control circuit activates the heating element, the metal shell, and the negative electrode tab; if the battery temperature is above the preset threshold, the charging control circuit controls the positive electrode tab, the battery cell, and the negative electrode tab.

[0044] By setting up a heating element, the heating element can be activated when the battery temperature is below a preset threshold, thus preventing the battery from operating at low temperatures. This reduces battery wear and extends its lifespan, ensuring that the battery maintains good performance even in low-temperature environments. It also allows the battery to operate within a more stable temperature range, reducing safety hazards. In addition, the use of a temperature sensor enables real-time monitoring of the battery temperature and activation of the heating function when necessary, reducing the rate of battery degradation and improving the cycle life of the cell. Attached Figure Description

[0045] 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 some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0046] Figure 1 This is a schematic diagram of a battery with a heating tab provided in an embodiment of this application;

[0047] Figure 2 This is a schematic diagram of a battery with two heating tabs provided in an embodiment of this application;

[0048] Figure 3 This is a schematic diagram of the assembly of the heating tab and temperature sensor in a battery provided in an embodiment of this application;

[0049] Figure 4 A circuit diagram of the heating element in a battery provided in an embodiment of this application;

[0050] Figure 5 This is a schematic diagram of the assembly of the heating tab, nickel plate, and temperature sensor in a battery provided in an embodiment of this application.

[0051] Figure 6 This is a schematic diagram of a metal casing in a battery provided in an embodiment of this application;

[0052] Figure 7 A side view of the metal casing in a battery provided in an embodiment of this application;

[0053] Figure 8 A graph showing the temperature versus time of the metal casing in the battery provided in this application embodiment.

[0054] Explanation of reference numerals in the attached figures:

[0055] 100-battery;

[0056] 110 - Metal casing;

[0057] 101 - Bottom shell;

[0058] 102 - Cover plate;

[0059] 111 - Groove;

[0060] 120-cell;

[0061] 121-Positive electrode ear;

[0062] 122-Negative electrode ear;

[0063] 130 - Heating element;

[0064] 131 - Heating tab;

[0065] 132-Nickel sheet;

[0066] 140 - Temperature sensor. Detailed Implementation

[0067] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, 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, 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. All other obtained embodiments are within the scope of protection of this application. In the absence of conflict, the following embodiments and features can be combined with each other.

[0068] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0069] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the communication between the internal cavities of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0070] It should be noted that in the description of this application, the terms "first," "second," and "third" are used only for the convenience of describing different cavity components and should not be construed as indicating or implying a sequential relationship, relative importance, or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," or "third" may explicitly or implicitly include at least one of those features.

[0071] Currently, efforts are focused on improving battery performance in low-temperature environments through two main approaches: ① researching and developing electrolytes and electrode materials with better low-temperature properties; ② researching low-temperature heating strategies for batteries. However, developing battery materials capable of withstanding low-temperature environments in the short term is difficult to guarantee. In comparison, researching low-temperature heating strategies from the perspective of the battery thermal management system is more feasible.

[0072] Current low-temperature heating strategies include direct current heating, alternating current heating, pulsed current heating, liquid-based heating, water channels that facilitate heat dissipation, and uniform heat distribution to the battery pack interior to achieve a uniform temperature rise in the battery.

[0073] However, none of the above solutions can effectively address the problems of slow charging speed and easy lithium plating at low temperatures.

[0074] To overcome the shortcomings of the prior art, the battery provided in this application, through the setting of a heating element, can avoid the battery from working for a long time at low temperatures by activating the heating element when the battery temperature is lower than a preset threshold, thereby reducing battery wear and extending its service life. This ensures that the battery can maintain good performance in low-temperature environments, allowing the battery to operate within a more stable temperature range and reducing safety hazards. In addition, the use of a temperature sensor enables real-time monitoring of the battery temperature and activation of the heating function when necessary, reducing the battery degradation rate and improving the cycle life of the cell.

[0075] The contents of this application will now be described in detail with reference to the accompanying drawings, so that those skilled in the art can have a clearer and more detailed understanding of the contents of this application.

[0076] Figure 1 This is a schematic diagram of a battery with a heating tab provided in an embodiment of this application. Figure 2 This is a schematic diagram of a battery with two heating tabs provided in an embodiment of this application. Figure 3 This is a schematic diagram of the assembly of the heating tab and temperature sensor in a battery according to an embodiment of this application. Figure 4 This is a circuit diagram of the heating element in a battery provided in an embodiment of this application.

[0077] like Figures 1 to 4As shown, this application embodiment provides a battery 100, including:

[0078] Metal shell 110, having a receiving cavity;

[0079] The battery cell 120 is housed in the receiving cavity, and the battery cell 120 has a positive electrode tab 121 and a negative electrode tab 122;

[0080] A heating element 130 is disposed on the battery 100. The heating element 130 is used to heat the battery 100. Along the thickness direction of the battery 100, the projection of one of the positive electrode tabs 121 and the negative electrode tabs 122 does not overlap with the projection of the heating element 130.

[0081] Temperature sensor 140 is used to detect the temperature of battery 100, and metal casing 110 and heating element 130 are connected.

[0082] The control unit includes a heating control circuit and a charging control circuit. When the battery is connected to an external power source, and the temperature of the battery 100 is lower than a preset threshold, the heating control circuit activates the heating element 130, the metal casing 110, and the negative electrode tab 122.

[0083] When the temperature of battery 100 is higher than a preset threshold, the charging control circuit controls the positive tab 121, the battery cell 120 and the negative tab 122.

[0084] like Figure 1 As shown, it should be noted that the metal shell 110 includes a bottom shell 101 and a cover plate 102, which together form a receiving cavity.

[0085] The bottom shell 101 includes a first sidewall and a through hole located on the first sidewall. A positive electrode connector is provided on the first sidewall. The positive electrode connector includes a positive electrode post and an insulating layer. The insulating layer is located on the positive electrode post and the first sidewall. The positive electrode post includes a positive electrode extension extending into the through hole. The positive electrode extension is connected to a positive electrode tab. The bottom shell is connected to a negative electrode tab 122. The heating element 130 is provided on the first sidewall.

[0086] The battery cell 120 is housed in a receiving cavity. The battery cell 120 includes a positive electrode plate and a negative electrode plate stacked together. The positive electrode plate includes a positive current collector and a positive electrode tab 121 extending from one side of the positive current collector. The negative electrode plate includes a negative current collector and a negative electrode tab 122 extending from one side of the negative current collector.

[0087] It should be noted that, understandably, the function of the receiving cavity is to house the battery cell 120. It is easy to understand that the receiving cavity is sealed to prevent side reactions from occurring inside the battery cell 120, which could affect the performance of the battery cell 120.

[0088] The size of the metal shell 110 can be set according to actual needs, and this application embodiment does not impose too many restrictions here.

[0089] In addition, it should be noted that the shape of the metal shell 110 is not limited in this embodiment. For example, the metal shell 110 can be in the shape of a cuboid, a cylinder or other regular shapes. Of course, the metal shell 110 can also be in other irregular shapes.

[0090] For example, the size or shape of the receiving cavity is matched with the size and shape of the battery cell 120. Specifically, it can be adjusted according to the actual situation. This application embodiment does not impose too many restrictions here.

[0091] It should be noted that the battery cell 120 in this embodiment can be a wound core or a stacked core, and the specific structure is not limited here.

[0092] It should be noted that the battery 100 in this embodiment also includes a heating element 130, which is used to heat the casing of the battery 100. The heat generated by the metal casing can solve the problems of slow charging speed and easy lithium plating at low temperatures. The specific structure is described below.

[0093] Among them, such as Figure 1 and Figure 2 As shown, the design that the projection of one of the positive tabs 121 and the negative tabs 122 does not overlap with the projection of the heating element 130 along the thickness direction X of the battery 100 is to avoid unnecessary influence on the position of the positive tabs 121 and the negative tabs 122 during the manufacturing process, thereby preventing interference and improving the reliability of the battery 100.

[0094] It should be noted that the battery 100 in this embodiment also includes a switch, which controls the start and stop of the heating program by closing the switch.

[0095] In some embodiments, the working principle is as follows: when the temperature sensor 140 receives a surface temperature of the battery 100 that is lower than a preset threshold, the activation switch remains open to force current to flow through the heating element 130, the metal casing 110, and the negative electrode tab 122. By passing the current through the metal casing with high resistance, a heating control circuit is formed, thereby generating a large amount of ohmic heat to rapidly heat the battery 100. When the temperature sensor 140 receives a surface temperature of the battery 100 that reaches or exceeds the preset threshold, the activation switch closes, allowing the current to bypass the metal casing 110. The charging control circuit controls the positive electrode tab 121, the battery cell 120, and the negative electrode tab 122, and the battery 100 performs normal charging and discharging.

[0096] In some embodiments, the temperature sensor 140 is placed near the heating element 130, rather than at the center of the battery cell 120.

[0097] It should be noted that the temperature at the heating element 130 is usually higher than the temperature at the center of the cell 120. In order to prevent the battery 100 from overheating at the heating temperature, it is recommended to place the temperature sensor 140 at the heating element 130 instead of at the center of the cell 120.

[0098] In addition, it should be noted that the preset threshold in this application can be in the range of 10℃-25℃.

[0099] By configuring the heating element 130 as described above, and activating it when the battery 100 temperature is below a preset threshold, the battery 100 can be prevented from operating at low temperatures, thereby reducing wear and tear on the battery 100, extending its lifespan, and ensuring that the battery 100 maintains good performance in low-temperature environments. This allows the battery 100 to operate within a more stable temperature range, reducing safety hazards. Furthermore, the use of the temperature sensor 140 enables real-time monitoring of the battery 100 temperature and activation of the heating function when necessary, reducing the rate of battery degradation and improving the cycle life of the battery cell.

[0100] like Figures 1 to 4 As shown, in some alternative embodiments, the heating element 130 includes at least one heating tab 131 disposed on the metal housing 110.

[0101] The above technical solution has the following advantages or beneficial effects: the design of setting the heating tab 131 on the metal shell 110 not only improves the heating efficiency and system reliability, but may also reduce costs and simplify the design.

[0102] In some embodiments, such as Figure 3 As shown, when the switch is turned on, the current from the external power supply flows from the positive terminal of the power supply to the positive terminal 121, the negative terminal 122, through the metal shell 110, the heating terminal 131, and finally to the negative terminal of the power supply.

[0103] When the switch is closed, the current from the external power supply flows from the positive terminal to the positive tab 121, the negative tab 122, and finally to the negative terminal.

[0104] In other words, when charging at low temperatures, the switch is turned on, and the current from the external power supply passes through the metal casing 110, causing the metal casing 110 to heat up. At this time, the metal casing 110 is connected to the heating tab 131.

[0105] When the temperature reaches the preset threshold, the switch is turned off, and the external power supply bypasses the metal casing 110, so the metal casing 110 is not heated at this time.

[0106] It should be noted that the heating tab 131 is connected to the negative electrode. In some embodiments, the heating tab 131 is directly disposed on the metal casing 110, which can more effectively transfer heat to the inside of the battery 100. This design can respond quickly to temperature changes and rapidly heat the battery 100 to the required operating temperature, thereby improving heating efficiency.

[0107] In addition, the setting of the heating tab 131 can achieve a more uniform heat distribution, avoid local overheating or overcooling, and thus optimize the thermal management of the battery 100.

[0108] In some embodiments, when a single heating tab 131 is designed, the battery pack 100 cannot be connected in series for heating; it can only be used for individual heating. When multiple heating tabs 131 are designed, multiple battery cells 120 can be connected in series for heating the battery pack 100.

[0109] In some embodiments, the straight-line distance between the heating tab 131 and the negative tab 122 can be designed to be as far as possible. This design can maximize the internal resistance provided by the metal shell and achieve higher heating efficiency.

[0110] In some alternative implementations, the distance between the heating tab 131 and the positive tab 121 is greater than or equal to 2 mm.

[0111] The above technical solution has the following advantages or beneficial effects: such a design prevents short circuits during charging and discharging.

[0112] In some embodiments, the heating tab 131 does not participate in the normal charging and discharging of the battery cell 120.

[0113] In other embodiments, when there is only one heating tab 131, the negative tab 122 is furthest from the heating tab 131 in a straight line; when there are multiple heating tabs 131, the two adjacent heating tabs 131 are furthest apart in a straight line.

[0114] In some alternative embodiments, the thickness of the heating tab 131 is 0.06 mm to 0.2 mm; and / or,

[0115] The width of the heating tab 131 is 4mm-20mm.

[0116] The above technical solution has the following advantages or beneficial effects: If the thickness and width of the heating tab 131 are too large, it will lead to an increase in material and processing costs, as well as an increase in overall weight. If the thickness and width of the heating tab 131 are too small, it may be susceptible to physical damage, such as bending or breakage, affecting its normal service life. It will also increase the complexity of the manufacturing process, leading to higher production costs and potentially affecting production efficiency.

[0117] In some embodiments, the thickness of the heating tab 131 is 0.06 mm, 0.07 mm, 0.08 mm, 0.09 mm, 0.1 mm, 0.11 mm, 0.12 mm, 0.13 mm, 0.14 mm, 0.15 mm, 0.16 mm, 0.17 mm, 0.18 mm, 0.19 mm, or 0.2 mm.

[0118] Figure 5 This is a schematic diagram of the assembly of the heating tab, nickel plate, and temperature sensor in the battery provided in an embodiment of this application.

[0119] like Figure 5 As shown, in some alternative embodiments, the heating element 130 further includes at least one nickel sheet 132 disposed on the battery cell 120, the nickel sheet 132 extending toward the metal shell 110 to protrude outward from the metal shell 110.

[0120] In some embodiments, the battery cell 120 has a stacked structure, and a nickel sheet 132 is disposed within the stacked structure. The nickel sheet 132 includes a body and at least one nickel sheet extension extending from one side of the body. An insulating layer is formed on two opposite side surfaces of the body. A lead-out is provided on the side wall of the bottom shell. The first end of the lead-out is connected to the nickel sheet extension, and the second end of the lead-out is connected to an external power source.

[0121] The above technical solution has the following advantages or beneficial effects: the addition of nickel sheet 132 and its specific design layout not only improve the thermal management efficiency of battery 100, but also enhance the performance stability and safety of battery 100.

[0122] Nickel has good thermal conductivity. By placing the nickel sheet 132 on the battery cell 120 and extending it to the outside of the metal shell 110, heat can be effectively transferred from the external environment to the inside of the battery cell 120, thereby improving the overall thermal conductivity.

[0123] Furthermore, in order to improve the heating efficiency, at least one nickel plate 132 can be inserted inside the battery 100, with two tabs extending from the nickel plate 132. When the temperature is lower than a preset threshold, the nickel plate 132 and the metal casing 110 can generate heat to heat the battery cell 120 individually or simultaneously.

[0124] Specifically, when the temperature is below the preset threshold, if switch K1 is closed and switch K2 is open, the battery 100 will be charged normally. If switch K1 is open and switch K2 is closed, the current will flow through the metal shell and the nickel plate 132, heating them simultaneously. If switch K1 is open and switch K2 is open, the current will only pass through the metal shell to generate heat. If switch K1 is closed and switch K2 is closed, the current will only pass through the nickel plate 132 to generate heat.

[0125] In some alternative embodiments, the internal resistance of the nickel sheet 132 is 40Ω-200mΩ; and / or,

[0126] The width of the nickel sheet 132 is 0.05mm-0.5mm.

[0127] The above technical solution has the following advantages or beneficial effects: by optimizing the internal resistance and width of the nickel sheet 132, heating and thermal management efficiency can be improved without significantly increasing energy consumption, thereby improving the efficiency of the entire battery 100 system.

[0128] By controlling the internal resistance of the nickel sheet 132 between 40Ω and 200mΩ, current flow and heat generation can be effectively managed. Lower internal resistance (close to 200mΩ) helps reduce energy loss and improve heating efficiency, while higher internal resistance (close to 40Ω) can be used to limit current and prevent overheating.

[0129] It should be noted that these parameter ranges allow designers to adjust the resistance and width of the nickel sheet 132 to achieve optimal performance based on specific application requirements. Appropriate selection of internal resistance and width can help prevent overheating and current overload, thereby improving system safety. This is particularly important in battery 100 applications where high reliability is required.

[0130] In some alternative implementations, the internal resistance of the nickel sheet 132 is 50Ω-100mΩ.

[0131] The above-described technical solution has the following advantages or beneficial effects: by setting the internal resistance between 50Ω and 100mΩ, the current flowing through the nickel sheet 132 can be effectively controlled. This resistance range allows for limiting current flow when needed to prevent overheating, while also providing sufficient current for heating when required.

[0132] By precisely controlling the generation of current and heat, the nickel sheet 132 can participate more effectively in the thermal management of the battery 100, helping to maintain the optimal operating temperature range of the battery 100 and extend the battery 100's lifespan.

[0133] Figure 6 This is a schematic diagram of a metal casing in a battery provided in an embodiment of this application. Figure 7 This is a side view of the metal casing in a battery provided in an embodiment of this application.

[0134] like Figure 6 and Figure 7 As shown, in some optional embodiments, a groove 111 is formed on the bottom shell 101, and the groove 111 recesses the metal shell in the direction of the inside of the bottom shell 101.

[0135] The above technical solution has the following advantages or beneficial effects: by designing a groove 111 on the bottom shell 101, the length of the current path can be effectively increased, thereby increasing the internal resistance. This increased internal resistance allows the current to generate more heat when passing through, thereby improving the heating efficiency.

[0136] In some embodiments, the shape and depth of the groove 111 can be adjusted according to specific application requirements, providing greater design flexibility to adapt to different battery 100 specifications and application scenarios.

[0137] In some alternative embodiments, the area S of the bottom shell 101 and the area s of the groove 111 satisfy the following relationship: s = a * S, 1 / 3 ≤ a ≤ 3 / 5; and / or,

[0138] The thickness H of the bottom shell 101 and the depth h of the groove 111 satisfy the following conditions: h = b * H, 1 / 3 ≤ b ≤ 2 / 3; and / or,

[0139] The width of groove 111 is 0.1um-100um.

[0140] The above technical solution has the following advantages or beneficial effects: if the total area of ​​the bottom shell 101 is S and the total area of ​​the groove 111 is s, then s=a*S,1 / 3≤a≤3 / 5.

[0141] Principle and effect: If the area of ​​groove 111 is too small, the heating efficiency will be low; if the area of ​​groove 111 is too large, it will affect the tensile strength of the metal shell and the appearance of the stacked core.

[0142] In some embodiments, if the thickness of the bottom shell 101 is H and the depth of the groove 111 is h, then h = b * H, 1 / 3 ≤ b ≤ 2 / 3.

[0143] Principle and effect: If the groove 111 is too shallow, the heating efficiency will not be significantly improved; if the groove 111 is too deep, it will affect the sealing of the metal shell and lead to leakage.

[0144] In some embodiments, the width L of the groove 111 is defined as being between 0.1µm and 100µm.

[0145] Principle and effect: If groove 111 is too narrow, it will affect the heating efficiency; if groove 111 is too wide, the appearance of cell 120 and the uniformity of current density cannot be guaranteed, which will affect the normal charging and discharging of cell 120.

[0146] In some alternative implementations,

[0147] The internal resistance of the metal casing 110 is 10Ω-500mΩ; and / or,

[0148] The heating power of the metal casing 110 is 2W-40W; and / or,

[0149] The thickness of the metal casing 110 is 0.06mm-0.2mm; and / or,

[0150] The hardness of the metal casing 110 is limited to 30 HRB-66 HRB; and / or,

[0151] The thermal conductivity of the metal shell 110 is 15 W / (m·K)-100 W / (m·K).

[0152] The above technical solution has the following advantages or beneficial effects: The metal casing, as the material of the metal casing 110 of the battery 100, not only affects the appearance and structure of the battery 100, but also its internal performance. Because the entire metal casing is connected to the negative electrode, if the internal resistance of the metal casing is high, it will affect the transport of electrons and ions between the electrode and the electrolyte, reducing the output current capability of the battery 100. If the internal resistance of the metal casing is low, the heating efficiency will be low.

[0153] Furthermore, the metal shell serves as the heating element, and its power is limited to between 2W and 40W according to the heating power formula P = I²R. Further, when the heating current is 1A-30A, the time to heat to the preset threshold (0℃-30℃) is limited to 30S-30min.

[0154] Figure 8 A graph showing the temperature versus time of the metal casing in the battery provided in this application embodiment.

[0155] like Figure 8 As shown, if the heating power is high, although it can raise the temperature of battery 100 and increase the reaction rate in a short time, the large temperature difference between battery 100 and the ambient temperature after heating stops causes rapid heat dissipation and cooling of battery 100, eventually bringing it close to the temperature before heating. This does not significantly increase the discharge energy of battery 100, and consumes more energy. If the heating power is low and the heating time is long, it will reduce efficiency, and the cell 120 is prone to heat dissipation ≥ heating, preventing the temperature of cell 120 from rising.

[0156] In some embodiments, the thickness H of the metal casing is limited to between 0.06 mm and 0.2 mm. Further, the hardness of the metal casing battery 100 is limited to between 30 HRB and 66 HRB, and the thermal conductivity is limited to between 15 W / (m·K) and 100 W / (m·K).

[0157] It should be noted that if the metal casing is too thick, it will not only reduce the battery's energy efficiency (ED), but also result in lower internal resistance compared to a thinner casing, thus reducing heating efficiency. If the metal casing is too thin, it will affect the battery's sealing performance and safety.

[0158] If the metal casing of a battery is too hard (e.g., 100), it will increase the difficulty and cost of processing, as well as the risk of breakage, reduce bending performance, and cause heat accumulation and safety hazards.

[0159] If the metal casing of the battery 100 is too soft, its ability to protect the battery cell 120 will be weakened, resulting in damage to the battery cell 120. In addition, the metal casing with low hardness has poor thermal conductivity and cannot effectively conduct the heat generated inside the battery 100, affecting its service life and charging and discharging efficiency.

[0160] Excessively high thermal conductivity can lead to uneven temperature distribution inside the battery 100, resulting in uneven electrochemical reactions and further affecting the performance and lifespan of the battery 100. Conversely, excessively low thermal conductivity can lead to excessively high temperature distribution inside the battery 100, causing excessively rapid electrochemical reactions and further affecting the performance and lifespan of the battery 100.

[0161] In some alternative embodiments, the metal casing 110 is one of a cold-rolled metal casing, a hot-rolled metal casing, a stainless metal casing, a galvanized metal casing, an aluminum alloy casing, and a titanium alloy casing; and / or,

[0162] The internal resistance of the metal casing 110 is 20Ω-100mΩ.

[0163] Metal shell materials may include cold-rolled steel, hot-rolled steel, stainless steel, galvanized steel, aluminum alloy, titanium alloy, etc.

[0164] High-resistivity materials such as iron oxide (Fe2O3), aluminum oxide (Al2O3), manganese dioxide (MnO2), and silicon dioxide (SiO2) can also be added to the metal shell.

[0165] It should be noted that cold-rolled steel is a type of steel produced through a cold rolling process, which has high strength and good processing performance.

[0166] Hot-rolled steel is a type of steel produced through a hot-rolling process, possessing high strength and good corrosion resistance. Its superior corrosion resistance extends the service life of battery 100. Stainless steel is another type of steel with good corrosion resistance, meeting the various requirements of the metal casing 110 of battery 100.

[0167] Galvanized steel is a type of steel produced through a galvanizing process, which gives it excellent corrosion resistance.

[0168] Aluminum alloy is a material with good corrosion resistance and lightweight properties, and is often used to manufacture the metal casing 110 of battery 100. It has high strength and good processing performance, which can meet the various requirements of the metal casing 110 of battery 100.

[0169] Titanium alloy is a material with high strength, low density, and good corrosion resistance, and is often used to manufacture the metal casing 110 of battery 100. It has high strength and good machinability, which can meet the various requirements of the metal casing 110 of battery 100.

[0170] In addition, the oxide increases the internal resistance of the battery 100 by forming an insulating layer on the surface of the metal casing.

[0171] Table 1: Heating Rate for Different Heating Currents

[0172]

[0173] In some embodiments, as shown in Table 1, when only a metal casing is used as the heating element, and the internal resistance R of the metal casing is selected as 50mΩ, when the surface temperature of the battery cell 120 is 10°C, different currents are applied to test whether the battery cell 120 can be heated to 25°C. The results show that when the current is 15A, the battery cell 120 cannot reach the preset threshold because the heating amount is less than the heat dissipation. However, when the current is 20A, 25A, and 30A, it can be heated to the preset threshold.

[0174] Table 2: Lithium Plating Status of Preheated and Unpreheated Cells

[0175] Charging time 500-cycle capacity retention Lithium plating Preheating cells 70min 87.35％ Non-lithium plating Unheated battery cells 92min 60.22％ Lithium plating

[0176] In other embodiments, only a metal shell is used as the heating element, with an internal resistance R of 50mΩ and a heating current of 30A.

[0177] The preset temperature threshold is set to 25℃, and the battery cell 120 is observed to cycle continuously in a 0℃ environment. When the temperature sensor 140 detects that the surface temperature of the battery cell 120 is lower than 25℃, the switch is turned off, the heating groove 111 is turned on, the current passes through the metal shell and heating begins. After heating reaches 25℃, the switch is closed and normal charging begins.

[0178] Charge / discharge procedure: Charge battery 100 at 1C current to the cutoff voltage, then charge at a constant voltage of 4.4V until the charging current is ≤0.05C and stop; after resting for 10 minutes, discharge at 1C current until the battery 100 voltage is ≤3.0V. Repeat the above procedure for 500T.

[0179] As shown in Table 2, the results showed that compared with cell 120 that was not preheated before charging, cell 120 that was preheated had a shorter charging time and a higher 500T capacity retention rate. Furthermore, when cell 120 was disassembled in a dry environment and the surface of the negative electrode of battery 100 was observed, grayish-black lithium plating was found on the negative electrode of cell 120 that was not preheated.

[0180] The battery provided in this application embodiment, through the setting of a heating element, can avoid the battery from working at low temperatures by activating the heating element when the battery temperature is lower than a preset threshold, thereby reducing battery wear and extending its service life. This ensures that the battery can maintain good performance in low-temperature environments, allowing the battery to work within a more stable temperature range and reducing safety hazards. In addition, the use of a temperature sensor enables real-time monitoring of the battery temperature and activation of the heating function when necessary, reducing the battery degradation rate and improving the cycle life of the cell.

[0181] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A battery (100) characterized in that, include: A metal shell (110) includes a bottom shell (101) and a cover plate (102), the bottom shell (101) and the cover plate (102) forming a receiving cavity; A battery cell (120) is housed within the receiving cavity. The battery cell (120) includes a positive electrode plate and a negative electrode plate. The positive electrode plate includes a positive current collector and a positive electrode tab (121) extending from one side of the positive current collector. The negative electrode plate includes a negative current collector and a negative electrode tab (122) extending from one side of the negative current collector. The bottom shell (101) includes a first sidewall and a through hole located on the first sidewall. A positive electrode connector is provided on the first sidewall. The positive electrode connector includes a positive electrode post and an insulating layer. The insulating layer is located on the positive electrode post and the first sidewall. The positive electrode post includes a positive electrode extension extending into the through hole. The positive electrode extension is connected to the positive electrode tab (121). The bottom shell (101) and the negative electrode tab (122) are electrically connected. Heating element (130) is electrically connected to the housing; A temperature sensor (140) is used to detect the temperature of the battery (100); The control unit includes a heating control circuit and a charging control circuit; when the battery is connected to an external power source, and the temperature of the battery (100) is lower than a preset threshold, the heating control circuit turns on the heating element (130), the metal shell (110) and the negative electrode tab (122). When the temperature of the battery (100) is higher than a preset threshold, the charging control circuit controls the positive tab (121), the battery cell (120) and the negative tab (122).

2. The battery (100) according to claim 1, characterized in that The heating element (130) includes at least one heating tab (131) disposed on the metal casing (110), and / or, along the thickness direction of the battery (100), the projection of one of the positive tab (121) and the negative tab (122) does not overlap with the projection of the heating element (130).

3. The battery (100) according to claim 2, characterized in that, The distance between the heating tab (131) and the positive tab (121) is greater than or equal to 2 mm.

4. The battery (100) according to claim 2, characterized in that, The thickness of the heating tab (131) is 0.06 mm to 0.2 mm; and / or, The width of the heating tab (131) is 4mm-20mm.

5. The battery (100) according to any one of claims 1-4, characterized in that, The heating element (130) further includes at least one nickel sheet (132). The battery cell (120) has a stacked structure. The nickel sheet (132) is disposed within the stacked structure. The nickel sheet (132) includes a body and at least one nickel sheet extension extending from one side of the body. An insulating layer is formed on two opposite side surfaces of the body. A lead-out is provided on the side wall of the bottom shell (101). The first end of the lead-out is connected to the nickel sheet extension, and the second end of the lead-out is connected to an external power source.

6. The battery (100) according to claim 5, characterized in that, The internal resistance of the nickel sheet (132) is 40Ω-200mΩ; and / or, The width of the nickel sheet (132) is 0.05mm-0.5mm.

7. The battery (100) according to claim 6, characterized in that, The internal resistance of the nickel sheet (132) is 50Ω-100mΩ.

8. The battery (100) according to any one of claims 2-4, characterized in that, A groove (111) is provided on the bottom shell (101), and the groove (111) is recessed toward the inside of the bottom shell (101); The area S of the bottom shell (101) and the area s of the groove (111) satisfy the following relationship: s = a * S, 1 / 3 ≤ a ≤ 3 / 5; and / or, The thickness H of the bottom shell (101) and the depth h of the groove (111) satisfy the following conditions: h = b * H, 1 / 3 ≤ b ≤ 2 / 3; and / or, The width of the groove (111) is 0.1um-100um.

9. The battery (100) according to claim 1, characterized in that, The internal resistance of the metal casing (110) is 10Ω-500mΩ; and / or, The heating power of the metal shell (110) is 2W-40W; and / or, The thickness of the metal shell (110) is 0.06 mm to 0.2 mm; and / or, The hardness of the metal shell (110) is limited to 30 HRB-66 HRB; and / or, The thermal conductivity of the metal shell (110) is 15 W / (m·K)-100 W / (m·K).

10. The battery (100) according to claim 9, characterized in that, The metal shell (110) is one of a cold-rolled metal shell, a hot-rolled metal shell, a stainless metal shell, a galvanized metal shell, an aluminum alloy shell, and a titanium alloy shell; and / or, The internal resistance of the metal shell (110) is 20Ω-100mΩ.

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