Battery and assembling method thereof

Abstract

The invention discloses a battery and an assembling method thereof, and relates to the technical field of energy storage equipment, the battery comprises a battery cell and a heating film attached to one side of the battery cell, one end of the heating film is provided with a bending lug, the bending lug is connected with a temperature protector, and the temperature protector is attached to the side, away from the heating film, of the battery cell; the temperature protector controls the heating state of the heating film. The bending lugs are arranged, so that the structure is simpler and more compact, the improvement cost is reduced, the temperature protector can be tightly attached to the battery core on the premise of being far away from the heating film, the influence of the heating temperature of the heating film on the temperature protector is reduced, and the control precision and the reliability of the temperature protector are improved. In addition, when the heating film heats the battery cell to the set temperature, the temperature protector is disconnected, and the heating film stops heating, so that the risk of failure of the battery cell caused by too high temperature is prevented, the failure rate can be reduced, and the reliability of the battery is improved. Therefore, the battery designed by the invention can simultaneously meet the improvement requirements of high reliability and low cost.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage equipment, and in particular to a battery and an assembling method thereof. Background Art

[0002] At present, lithium batteries are widely used in smart phones, tablet computers, electric vehicles and other devices due to their advantages such as high energy density, lightness, fast charging and no memory effect. Their performance and life directly affect the use effect and service life of the equipment.

[0003] In low temperature environments, the viscosity of the electrolyte will increase, and even partially solidify, causing the conductivity of lithium-ion batteries to decrease, the ion conduction speed to slow down, and the discharge capacity and charging efficiency of the battery to be affected; in addition, the diffusion rate of lithium ions in the active material is reduced, and the charge transfer impedance is significantly increased, resulting in an increase in the internal resistance of the battery, affecting the performance of the battery. The impact of low temperature on lithium batteries is mainly manifested in changes in electrolyte properties, a decrease in chemical reaction rates, and a reduction in available capacity, resulting in a significant impact on the performance of lithium batteries in low temperature environments, including a decrease in energy release capacity, reduced power, and a decrease in actual available capacity. In order to cope with the impact of low temperature environments on the performance of lithium batteries, it is particularly necessary to develop lithium batteries that are adapted to low temperature environments.

[0004] Existing technologies improve the performance of lithium batteries in low temperature environments by improving electrolytes, electrode materials, and using solid electrolytes. However, due to the limitations of existing technology levels, existing improvement methods are difficult to simultaneously meet the improvement requirements of high reliability and low cost. Summary of the invention

[0005] In view of this, the purpose of the present invention is to provide a battery and an assembly method thereof, wherein a heating film is directly attached to the surface of the battery cell, and a temperature protector is arranged on the heating film, and the surface temperature of the battery cell is controlled by switching on and off, thereby solving the technical problem that the existing improvement methods are difficult to simultaneously meet the improvement requirements of high reliability and low cost.

[0006] To achieve the above-mentioned purpose, the present invention provides a battery, comprising a battery cell and a heating film attached to one side of the battery cell; a bending ear is provided at one end of the heating film, the bending ear is connected to a temperature protector, and the temperature protector is attached to a side of the battery cell away from the heating film; the temperature protector controls the heating state of the heating film.

[0007] Preferably, a protection plate is further included, and the heating core of the heating film is connected to the protection plate through a wire;

[0008] When the ambient temperature of the battery cell does not reach the set temperature, the temperature protector is in the on state, the heating core is electrically connected to the battery cell through the protection board, and the heating core heats the battery cell;

[0009] When the surface temperature of the battery cell reaches the set temperature, the temperature protector is in the disconnected state, the heating core remains disconnected from the battery cell, and the heating core stops heating the battery cell.

[0010] Preferably, a protection plate is further included, and the heating core of the heating film is electrically connected to the controller of the protection plate through a wire;

[0011] When the ambient temperature of the battery cell does not reach the set temperature, the temperature protector is in the on state, and the temperature protector feeds back a normal signal to the controller through the wire. After judgment and processing, the controller transmits the generated conduction current to the heating core through the wire to control the heating core to heat the battery cell;

[0012] When the surface temperature of the battery cell reaches the set temperature, the temperature protector is in the disconnected state, the heating core remains disconnected from the battery cell, and the heating core stops heating the battery cell.

[0013] Preferably, the temperature protector comprises a body, a fixed terminal, a rocker terminal, a thermistor and a bimetallic strip; the fixed terminal and the rocker terminal are respectively inserted into the body from both sides of the body; the thermistor is fixedly arranged at one end of the fixed terminal located in the body; the bimetallic strip is fixedly arranged at the thermistor;

[0014] When the heating temperature of the bimetallic strip by the thermistor reaches the set temperature, the bimetallic strip is heated and deformed in the reverse direction, and the bimetallic strip pushes the moving contact of the rocker terminal to separate from the fixed terminal, and the temperature protector remains in the disconnected state;

[0015] When the heating temperature of the bimetal strip by the thermistor does not reach the set temperature, the bimetal strip rebounds, and the rocker terminal resets with the bimetal strip until the moving contact contacts the fixed terminal, and the temperature protector remains in the on state.

[0016] Preferably, the bending ear is integrally provided at one end of the heating film, and the bending ear is bent from the bottom end of the heating film to one side of the battery core.

[0017] Preferably, the other end of the heating film is integrally provided with a connecting ear, and the connecting ear is provided with a plurality of first welding pads; the protective plate is provided with a plurality of second welding pads; all the first welding pads are connected one-to-one with all the second welding pads through wires; all the first welding pads are distributed in a stepped manner along the length direction of the heating film, and all the second welding pads are distributed linearly along the length direction of the heating film.

[0018] Preferably, the length of the second soldering pad and the length of the core of the wire satisfy the following relationship: Lh=Ld, where Lh is the length of the second soldering pad and Ld is the length of the core of the wire; the width of the second soldering pad and the width of the core of the wire satisfy the following relationship: Wh≥Wd, where Wh is the width of the second soldering pad and Wd is the width of the core of the wire; along the length direction of the heating film, the distance between two adjacent second soldering pads and the width of the second soldering pad satisfy the following relationship: Sh=Wh, where Sh is the distance between two adjacent second soldering pads and Wh is the width of the second soldering pad.

[0019] Preferably, the protection plate is affixed with a plurality of connecting sheets for connecting the tabs of the battery cell;

[0020] In the width direction of the heating film, the minimum distance between the second pad and the edge of the protection plate is the set edge distance, and the set edge distance satisfies: D1 ≥ 1.5 mm, where D1 is the set edge distance;

[0021] In the width direction of the heating film, the distance between the second soldering pad and the adjacent connecting piece is the set spacing distance, and the set spacing distance satisfies: D2≥1.5mm, where D2 is the set spacing distance.

[0022] Preferably, the distance between the connecting ear and the protection plate is a set reserved distance, and the set reserved distance satisfies: D3 ≥ 15 mm, where D3 is the set reserved distance; and the length of the wire is a set reserved length, and the set reserved length satisfies: Ld ≥ 15 mm, where Ld is the set reserved length.

[0023] Preferably, along the length direction of the heating film, the length of the connecting ear satisfies: Lc≥15mm and Lc=1 / 2We, where Lc is the length of the connecting ear and We is the width of the heating film;

[0024] In the width direction of the heating film, the width of the connecting ear satisfies: Wc≥7mm and Wc=2Dd, wherein Wc is the width of the connecting ear and Dd is the thickness of the wire.

[0025] Preferably, the angle between the electrode tab of the battery cell and the connecting piece is greater than 45°.

[0026] Preferably, the distance from the temperature protector to the bottom of the battery cell is a set reserved distance, and the set reserved distance satisfies: D4≥5mm, and D4 is the set reserved distance.

[0027] Preferably, the heating film comprises a first insulating film and a second insulating film respectively attached and fixed to both sides of the heating core, and the first insulating film and the heating core and the second insulating film and the heating core are bonded by thermal conductive adhesive.

[0028] Preferably, the heating area of ​​the heating film and the large surface area of ​​the battery cell satisfy: Se:Sc=1:1, Se is the heating area of ​​the heating film, and Sc is the large surface area of ​​the battery cell.

[0029] Preferably, the battery cell comprises a first battery cell and a second battery cell which are adjacently arranged, and the heating film is attached between the first battery cell and the second battery cell; the deep pit surface of the first battery cell is opposite to the deep pit surfaces of the second battery cell.

[0030] The present invention also provides a battery assembly method, which is applied to the above-mentioned battery, and the steps include:

[0031] Welding the first end of the wire to the first welding pad of the heating film;

[0032] Soldering the second end of the wire to the second soldering pad of the protection board;

[0033] Adjust the positions of the first battery cell and the second battery cell until the deep pit surfaces of the two batteries face each other;

[0034] Welding the tabs of the first battery cell and the second battery cell to the connecting piece of the protection plate;

[0035] The heating film is bonded between the first battery core and the second battery core.

[0036] Compared with the background technology, the present invention directly attaches a heating film to one side of the battery cell, and uses the heating film to directly heat the battery cell, so that the battery can cope with low temperature environments, the overall structure of the battery is slightly improved, and the improvement cost is low. In the present invention, a bending ear is provided at one end of the heating film, and the bending ear is connected to a temperature protector. The temperature protector is attached to the side of the battery cell away from the heating film, which can not only make the structure simpler and more compact, reduce the improvement cost, but also make the temperature protector close to the battery cell on the premise of being away from the heating film, reduce the influence of the heating temperature of the heating film on the temperature protector, improve the control accuracy of the temperature protector, and improve reliability. In addition, when the heating film heats the battery cell to the set temperature, the temperature protector is disconnected, and the heating film stops heating, which prevents the risk of battery cell failure due to excessive temperature, and can also reduce the failure rate and improve the reliability of the battery. Therefore, the battery designed by the present invention can meet the improvement requirements of high reliability and low cost at the same time.

[0037] The battery assembly method provided by the present invention is relatively simple to operate, has firm welding points, and can also enable the battery to simultaneously meet the improvement requirements of high reliability and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0039] Figure 1 A side view of a battery provided by a specific embodiment of the present invention;

[0040] Figure 2 for Figure 1 Exploded diagram of

[0041] Figure 3 for Figure 2 Side view of

[0042] Figure 4 An axonometric diagram of a battery provided in accordance with a specific embodiment of the present invention;

[0043] Figure 5 for Figure 4 A partial enlarged view of middle A;

[0044] Figure 6 for Figure 4 The main view;

[0045] Figure 7 for Figure 1 Front view of the middle heating film after unfolding;

[0046] Figure 8 for Figure 7 A partial enlarged view of B in the middle;

[0047] Fig. 9 for Figure 1 Schematic diagram of the back side of the middle heating film after unfolding;

[0048] Fig.10 for Figure 1 Schematic diagram of the connection between the heating film, wires and protection board;

[0049] Fig.11 for Fig.10 A partial enlarged view of

[0050] Fig.12 for Figure 1 Exploded view of the heating film;

[0051] Fig.13 for Figure 1 Diagram of disconnection state of medium temperature protector;

[0052] Fig.14 for Figure 1Diagram of the connected state of the medium temperature protector;

[0053] The reference numerals are as follows:

[0054] Battery core 1, heating film 2, temperature protector 3, protection plate 4 and wire 5;

[0055] A tab 10, a first battery cell 11 and a second battery cell 12;

[0056] The heating core 201, the first insulating film 202 and the second insulating film 203;

[0057] Bending ear 21, connecting ear 22 and first welding pad 23;

[0058] The body 31, the fixed terminal 32, the rocker terminal 33, the thermistor 34 and the bimetallic strip 35;

[0059] The second pad 41 and the connection piece 42 . DETAILED DESCRIPTION

[0060] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0061] In order to enable those skilled in the art to better understand the scheme of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0062] The embodiment of the present invention discloses a battery, as shown in the attached Figure 1 As shown, it includes a battery cell 1 and a heating film 2. The battery cell 1 includes a plurality of battery cells 1, which are stacked and arranged to store electrical energy. Figures 1 to 4 As shown, the heating film 2 is directly attached to one side of the battery cell 1. The heating film 2 is used to heat the surface of the battery cell 1, so that the temperature of the battery cell 1 and its environment are increased, so that the battery can cope with low temperature environments. The overall structure of the battery is slightly improved and the improvement cost is low.

[0063] As attached Figure 2 and 3As shown, a bending ear 21 is provided at one end of the heating film 2, and a temperature protector 3 is fixed to the bending ear 21, so that the temperature protector 3 is attached to the side of the battery cell 1 away from the heating film 2, and the temperature protector 3 controls the heating state of the heating film 2 according to the actual temperature of the battery cell 1. The setting of the bending ear 21 eliminates the need for additional components to fix the temperature protector 3, making the structure simpler and more compact, and the improvement cost is lower; moreover, the temperature protector 3 is close to the battery cell 1 while being away from the heating film 2, reducing the influence of the heating temperature of the heating film 2 on the temperature protector 3, improving the control accuracy of the temperature protector 3, and improving reliability.

[0064] The temperature protector 3 controls the heating state of the heating film 2. The temperature protector 3 is preferably a bimetallic temperature control switch, which is small in size and has high sensitivity and fast response characteristics. The temperature protector 3 is small in size and is attached to the large surface of the battery cell 1. The temperature protector 3 only occupies 5% of the large surface area of ​​the battery cell 1, and the volume of the temperature protector 3 is 2% of the volume of the battery cell 1, which can improve the space utilization of the battery and increase the energy density of the battery.

[0065] The present invention can not only utilize the heating film 2 to directly heat the battery core 1 , but also utilize the temperature protector 3 to control the heating state of the heating film 2 , and can simultaneously meet the improvement requirements of high reliability and low cost.

[0066] As a preferred embodiment, as shown in the attached Figures 1 to 6 As shown, the battery further includes a protection plate 4, which is located directly above all the battery cells 1. The heating core 201 of the heating film 2 is connected to the protection plate 4 via a wire 5.

[0067] When the ambient temperature of the battery cell 1 does not reach the set temperature, the temperature protector 3 is in the on state, the heating core 201 is electrically connected to the battery cell 1 through the protection board 4, the temperature protector 3 controls the heating core 201 to enter the heating state, and transfers the heat generated in a short time to the battery cell 1. The heating core 201 heats the battery cell 1, and the battery cell 1 heats up rapidly, so that the battery cell 1 can be charged normally, or even charged efficiently, thereby solving the problem that the battery cell 1 cannot be charged in a low temperature environment.

[0068] When the surface temperature of the battery cell 1 reaches the set temperature, the temperature protector 3 is in the disconnected state, the heating core 201 remains disconnected from the battery cell 1, the temperature protector 3 controls the heating core 201 to enter the stop heating state, the heating core 201 stops heating the battery cell 1, and prevents the battery cell 1 from failing due to high temperature, thereby improving the reliability of the battery cell 1.

[0069] As another preferred embodiment, the battery further comprises a protection plate 4, which is located directly above all the battery cells 1. The heating core 201 of the heating film 2 is electrically connected to the controller of the protection plate 4 via a wire 5.

[0070] When the ambient temperature of the battery cell 1 does not reach the set temperature, the temperature protector 3 is in the on state, and the temperature protector 3 feeds back a normal signal to the controller through the wire 5. After judgment and processing, the controller transmits the generated conduction current to the heating core 201 through the wire 5, controls the heating core 201 to start heating, and transfers the heat generated in a short time to the battery cell 1, heating the battery cell 1. The battery cell 1 heats up rapidly, so that the battery cell 1 can be charged normally, or even charged efficiently, thereby solving the problem that the battery cell 1 cannot be charged in a low temperature environment.

[0071] When the surface temperature of the battery cell 1 reaches the set temperature, the temperature protector 3 is in the disconnected state, the heating core 201 remains disconnected from the battery cell 1, and the heating core 201 stops heating the battery cell 1 to prevent the battery cell 1 from failing due to high temperature, thereby improving the reliability of the battery cell 1.

[0072] It should also be noted that the set temperature in the text refers to the maximum temperature that the battery cell 1 can withstand, which can specifically reach 72°C.

[0073] As a preferred embodiment, as shown in the attached Fig.13 and 14 As shown, the temperature protector 3 includes a body 31, a fixed terminal 32, a rocker terminal 33, a thermistor 34 and a bimetallic strip 35. The fixed terminal 32 and the rocker terminal 33 are inserted into the body 31 from both sides of the body 31 respectively; the thermistor 34 is fixed to one end of the fixed terminal 32 located in the body 31; and the bimetallic strip 35 is fixed to the thermistor 34. The bimetallic strip 35 is formed by laminating two metal sheets with different thermal expansion coefficients.

[0074] When the heating temperature of the bimetal 35 by the thermistor 34 reaches the set temperature, the bimetal 35 is heated and deformed in the reverse direction. Due to the different thermal expansion coefficients, the bimetal 35 pushes the moving contact of the rocker terminal 33 to separate from the fixed terminal 32, and the temperature protector 3 remains in the disconnected state. Fig.13 As shown;

[0075] When the heating temperature of the bimetal 35 by the thermistor 34 does not reach the set temperature, the bimetal 35 rebounds, and the rocker terminal 33 is reset along with the bimetal 35 until the moving contact of the rocker terminal 33 contacts the fixed terminal 32, and the temperature protector 3 remains in the on state. Fig.14 shown.

[0076] As attached Figure 2 and 3As shown, the bending ear 21 is integrally provided at one end of the heating film 2, and the bending ear 21 is bent from the bottom end of the heating film 2 to one side of the battery cell 1. The bending ear 21 is fixed with a temperature protector 3, so that the temperature protector 3 is attached to the side of the battery cell 1 away from the heating film 2, and the temperature protector 3 controls the heating state of the heating film 2 according to the actual temperature of the battery cell 1. It should be supplemented that in the folded state, the bending ear 21 is U-shaped, as shown in the attached figure. Figure 2 and 3 In the unfolded state, the bending ear 21 is a rectangular frame, that is, a rectangular hole is formed in the center of the bending ear 21, as shown in the attached Figures 7 to 9 As shown, it is ensured that the bending ear 21 has less consumables and reduces the cost.

[0077] As attached Figure 2 , 3 As shown in FIGS. 7 and 9, the other end of the heating film 2 (i.e., the end away from the bending ear 21) is integrally provided with a connecting ear 22, and the connecting ear 22 is provided with a plurality of first pads 23, and the protection plate 4 is provided with a plurality of second pads 41. All the first pads 23 and all the second pads 41 are connected one by one through the wire 5. Soldering is adopted between the first pad 23 and the wire 5 and between the second pad 41 and the wire 5. In order to increase the utilization space of the connecting ear 22, all the first pads 23 are distributed in a stepped manner in the length direction of the heating film 2, as shown in the attached figure. Fig.12 In order to keep the wire 5 and the tab 10 of the battery cell 1 at an appropriate distance, the second pads 41 are arranged along the edge of the protection plate 4, and all the second pads 41 are linearly distributed along the length direction of the heating film 2, as shown in the attached Fig.10 and 11 As shown, the wire 5 is prevented from contacting the tab 10 .

[0078] As attached Fig.11 As shown, the length of the second solder pad 41 and the length of the core of the wire 5 satisfy: Lh=Ld, Lh is the length of the second solder pad 41, and Ld is the length of the core of the wire 5; the width of the second solder pad 41 and the width of the core of the wire 5 satisfy: Wh≥Wd, Wh is the width of the second solder pad 41, and Wd is the width of the core of the wire 5; this ensures that the second solder pad 41 has enough space to store solder paste, so that the solder paste on the second solder pad 41 can completely cover the core of the wire 5, and prevent the solder paste from overflowing from the boundary of the second solder pad 41, ensuring that each wire 5 is firmly soldered to the protection board 4, and preventing the solder joints of each wire 5 on the protection board 4 from contacting each other, causing the signal to be unable to be transmitted or the current to be short-circuited, thereby improving the connection reliability between the protection board 4 and the wire 5.

[0079] Along the length direction of the heating film 2, the distance between two adjacent second soldering pads 41 and the width of the second soldering pad 41 satisfy: Sh=Wh, Sh is the distance between two adjacent second soldering pads 41, and Wh is the width of the second soldering pad 41, thereby ensuring that the spacing between two adjacent second soldering pads 41 is appropriate, avoiding cross-contamination caused by solder paste overflow due to the small spacing between two adjacent second soldering pads 41 during welding, reducing the current short-circuit temperature caused by solder paste overflow, reducing the risk of failure at the connection of each wire 5, and improving the reliability of each wire 5.

[0080] As attached Figure 5 As shown, the protection plate 4 is attached with a plurality of connecting sheets 42 for connecting the tabs 10 of the battery cell 1. The connecting sheets 42 are preferably nickel sheets, but are not limited thereto. Fig.11 As shown, along the width direction of the heating film 2, the minimum distance between the second soldering pad 41 and the edge of the protective plate 4 is the set edge distance, and the set edge distance satisfies: D1 ≥ 1.5 mm, where D1 is the set edge distance, ensuring that the distance from the second soldering pad 41 to the edge of the protective plate 4 is appropriate to prevent the solder paste of the second soldering pad 41 from overflowing outside the protective plate 4.

[0081] As attached Fig.11 As shown, along the width direction of the heating film 2, the distance between the second soldering pad 41 and the adjacent connecting piece 42 is a set spacing distance, and the set spacing distance satisfies: D2 ≥ 1.5 mm, where D2 is the set spacing distance; this avoids the solder paste of the second soldering pad 41 overflowing to the connecting piece 42 due to the small spacing between the second soldering pad 41 and the connecting piece 42, causing a short circuit between the wire 5 and the pole ear 10 of the battery cell 1, thereby improving reliability.

[0082] As attached Fig.10 As shown, the distance between the connecting ear 22 and the protection plate 4 is a set reserved distance, and the set reserved distance satisfies: D3 ≥ 15 mm, where D3 is the set reserved distance; and, as shown in the attached Fig. 9 As shown, the length of the wire 5 is a set reserved length, and the set reserved length satisfies: Ld≥15mm, where Ld is the set reserved length, which reserves sufficient bending length for the bending of the wire 5, so that the length of the wire 5 is moderate, avoiding the waste of resources caused by the length of each wire 5 being too long, and avoiding the length of the wire 5 being too short to affect the bending.

[0083] As attached Fig.10 As shown, along the length direction of the heating film 2, the length of the connecting ear 22 satisfies: Lc ≥ 15 mm and Lc = 1 / 2 We, where Lc is the length of the connecting ear 22 and We is the width of the heating film 2, which can ensure that the connecting ear 22 has enough space to connect the wires 5 and that the connecting ear 22 has enough strength to provide support for the wires 5. Figure 1 and 10As shown, along the width direction of the heating film 2, the width of the connecting ear 22 satisfies: Wc≥7mm and Wc=2Dd, wherein Wc is the width of the connecting ear 22, and Dd is the thickness of the wire 5, thereby improving the connection reliability and safety between each wire 5 and the connecting ear 22.

[0084] As attached Figure 5 As shown, the angle between the pole ear 10 of the battery cell 1 and the connecting piece 42 is greater than 45°, which increases the movable space of each wire 5 between the protection plate 4 and the heating film 2 and improves the connection safety of each wire 5.

[0085] As attached Figure 6 As shown, the temperature protector 3 is arranged near the bottom end of the battery cell 1, and the distance from the temperature protector 3 to the bottom end of the battery cell 1 is a set reserved distance, and the set reserved distance satisfies: D4 ≥ 5mm, D4 is the set reserved distance, preferably 8mm, leaving enough bending space for the bending ear 21 to ensure that the bending ear 21 can be tightly attached to the bottom side and large surface of the battery cell 1 after bending, so that the temperature protector 3 is firmly attached to the large surface of the battery cell 1.

[0086] As attached Fig.12 As shown, the heating film 2 is a sandwich structure. In addition to the heating core 201, it also includes a first insulating film 202 and a second insulating film 203 respectively attached and fixed on both sides of the heating core 201. The first insulating film 202 and the heating core 201, and the second insulating film 203 and the heating core 201 are bonded by thermal conductive adhesive, so that the heating film 2 has good thermal conductivity and electrical insulation performance. The heating core 201 is made of a heating material with good electrical conductivity, such as nickel alloy. The first insulating film 202 and the second insulating film 203 are preferably polyimide films, which have good electrical insulation and thermal conductivity. Of course, the first insulating film 202 and the heating core 201, and the second insulating film 203 and the heating core 201 can also be fixed by hot pressing, but it is not limited to this.

[0087] As attached Figure 2 As shown, the heating area of ​​the heating film 2 and the large surface area of ​​the battery cell 1 satisfy: Se: Sc = 1:1, Se is the heating area of ​​the heating film 2, Sc is the large surface area of ​​the battery cell 1, so that the heating film 2 completely covers the large surface of the battery cell 1 to ensure that the battery cell 1 is heated evenly. The large surface of the battery cell 1 in this article specifically refers to the two largest surfaces of the battery cell 1.

[0088] As attached Figure 2 and 3As shown, as a preferred embodiment, the heating film 2 is attached and fixed between the large surfaces of the two battery cells 1. The battery cell 1 includes a first battery cell 11 and a second battery cell 12 arranged adjacently, and the heating film 2 is attached between the first battery cell 11 and the second battery cell 12; the deep pit surface of the first battery cell 11 is opposite to the horizontal pit surface of the second battery cell 12, so that the first battery cell 11 and the second battery cell 12 are fixedly connected by means of the heating film 2, and the heating film 2 heats the first battery cell 11 and the second battery cell 12 at the same time, with less heat loss and higher heat utilization rate, which is conducive to reducing energy consumption.

[0089] The present invention also provides a battery assembly method, which is applied to the above-mentioned battery, and the steps include:

[0090] The first step is to weld the first end of the wire 5 to the first welding pad 23 of the heating film 2; wherein the first welding pad 23 is arranged on the connecting ear 22 of the heating film 2;

[0091] Step 2: Weld the second end of the wire 5 to the second pad 41 of the protection plate 4, so that the heating core 201 of the heating film 2 is electrically connected to the protection plate 4 through the wire 5;

[0092] Step 3: Adjust the positions of the first battery cell 11 and the second battery cell 12 until the deep pit surface of the first battery cell 11 is opposite to the deep pit surface of the second battery cell 12; that is, before welding the battery cell 1 and the protection plate 4, adjust the positions of the battery cells 1 so that the battery cells 1 are stacked together regularly;

[0093] Step 4: Weld the tabs 10 of the first battery cell 11 and the second battery cell 12 to the connecting piece 42 of the protection plate 4;

[0094] The fifth step is to adhere the heating film 2 between the first battery cell 11 and the second battery cell 12; that is, after the battery cell 1 and the protection plate 4 are welded, the heating film 2 is fixed between the two battery cells 1 to avoid that part of the wire 5 or the tab 10 cannot be welded in place due to the limited space between the battery cell 1 and the protection plate 4, and to ensure that the welding position of each wire 5 and each tab 10 is accurate, the welding point is firm, and the reliability is improved.

[0095] The entire assembly process of the present invention is relatively independent, time-consuming, convenient to operate, and has a low improvement cost; moreover, the present invention adheres the heating film 2 after the battery core 1 and the heating film 2 are respectively welded to the protection plate 4, so the welding points are firm and the reliability is high.

[0096] It should be noted that, in this specification, relational terms such as first and second are merely used to distinguish one entity from other entities, but do not necessarily require or imply any actual relationship or order between these entities.

[0097] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core ideas of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A battery, characterized in that: The invention comprises a battery cell (1) and a heating film (2) attached to one side of the battery cell (1); a bending ear (21) is provided at one end of the heating film (2); the bending ear (21) is connected to a temperature protector (3); the temperature protector (3) is attached to a side of the battery cell (1) away from the heating film (2); the temperature protector (3) controls the heating state of the heating film (2).

2. The battery according to claim 1, characterized in that It also comprises a protection plate (4), and the heating core (201) of the heating film (2) is connected to the protection plate (4) via a wire (5); When the ambient temperature of the battery core (1) does not reach the set temperature, the temperature protector (3) is in an on state, the heating core (201) is electrically connected to the battery core (1) via the protection plate (4), and the heating core (201) heats the battery core (1); When the surface temperature of the battery core (1) reaches the set temperature, the temperature protector (3) is in a disconnected state, the heating core (201) remains disconnected from the battery core (1), and the heating core (201) stops heating the battery core (1).

3. The battery according to claim 1, characterized in that It also comprises a protection plate (4), and the heating core (201) of the heating film (2) is electrically connected to the controller of the protection plate (4) via a wire (5); When the ambient temperature of the battery cell (1) does not reach the set temperature, the temperature protector (3) is in an on state, the temperature protector (3) feeds back a normal signal to the controller via the wire (5), and the controller, after judgment and processing, transmits the generated conduction current via the wire (5) to the heating core (201), thereby controlling the heating core (201) to heat the battery cell (1); When the surface temperature of the battery core (1) reaches the set temperature, the temperature protector (3) is in a disconnected state, the heating core (201) remains disconnected from the battery core (1), and the heating core (201) stops heating the battery core (1).

4. The battery according to claim 2 or 3, characterized in that: The temperature protector (3) comprises a body (31), a fixed terminal (32), a rocker terminal (33), a thermistor (34) and a bimetallic strip (35); the fixed terminal (32) and the rocker terminal (33) are respectively inserted into the body (31) from two sides of the body (31); the thermistor (34) is fixedly mounted at one end of the fixed terminal (32) located in the body (31); and the bimetallic strip (35) is fixedly mounted on the thermistor (34); When the heating temperature of the bimetallic strip (35) by the thermistor (34) reaches the set temperature, the bimetallic strip (35) is heated and deformed in the reverse direction, the bimetallic strip (35) pushes the moving contact of the rocker terminal (33) to separate from the fixed terminal (32), and the temperature protector (3) maintains the disconnected state; When the heating temperature of the bimetallic strip (35) by the thermistor (34) does not reach the set temperature, the bimetallic strip (35) rebounds, and the rocker terminal (33) is reset along with the bimetallic strip (35) until the moving contact contacts the fixed terminal (32), and the temperature protector (3) maintains the on state.

5. The battery according to claim 2 or 3, characterized in that: The bending ear (21) is integrally arranged at one end of the heating film (2), and the bending ear (21) is bent from the bottom end of the heating film (2) to one side of the battery core (1).

6. The battery according to claim 5, characterized in that The other end of the heating film (2) is integrally provided with a connecting ear (22), and the connecting ear (22) is provided with a plurality of first solder pads (23); the protection plate (4) is provided with a plurality of second solder pads (41); all the first solder pads (23) and all the second solder pads (41) are connected in a one-to-one correspondence via the wires (5); all the first solder pads (23) are distributed in a stepped manner along the length direction of the heating film (2), and all the second solder pads (41) are distributed in a linear manner along the length direction of the heating film (2).

7. The battery according to claim 6, characterized in that The length of the second soldering pad (41) and the length of the core of the wire (5) satisfy the following relationship: Lh=Ld, where Lh is the length of the second soldering pad (41) and Ld is the length of the core of the wire (5); the width of the second soldering pad (41) and the width of the core of the wire (5) satisfy the following relationship: Wh≥Wd, where Wh is the width of the second soldering pad (41) and Wd is the width of the core of the wire (5); along the length direction of the heating film (2), the distance between two adjacent second soldering pads (41) and the width of the second soldering pad (41) satisfy the following relationship: Sh=Wh, where Sh is the distance between two adjacent second soldering pads (41) and Wh is the width of the second soldering pad (41).

8. The battery according to claim 6, characterized in that The protection plate (4) is affixed with a plurality of connection pieces (42) for connecting the tabs (10) of the battery cell (1); In the width direction of the heating film (2), the minimum distance between the second soldering pad (41) and the edge of the protection plate (4) is a set edge distance, and the set edge distance satisfies: D1 ≥ 1.5 mm, where D1 is the set edge distance; In the width direction of the heating film (2), the distance between the second soldering pad (41) and the adjacent connecting piece (42) is a set spacing distance, and the set spacing distance satisfies: D2≥1.5 mm, where D2 is the set spacing distance.

9. The battery according to claim 6, characterized in that The distance between the connecting ear (22) and the protection plate (4) is a set reserved distance, and the set reserved distance satisfies: D3 ≥ 15 mm, where D3 is the set reserved distance; and the length of the wire (5) is a set reserved length, and the set reserved length satisfies: Ld ≥ 15 mm, where Ld is the set reserved length.

10. The battery according to claim 6, characterized in that In the length direction of the heating film (2), the length of the connecting ear (22) satisfies: Lc ≥ 15 mm and Lc = 1 / 2 We, where Lc is the length of the connecting ear (22) and We is the width of the heating film (2); In the width direction of the heating film (2), the width of the connecting ear (22) satisfies: Wc≥7mm and Wc=2Dd, wherein Wc is the width of the connecting ear (22) and Dd is the thickness of the conducting wire (5).

11. The battery according to claim 8, characterized in that The angle between the pole ear (10) of the battery cell (1) and the connecting sheet (42) is greater than 45°.

12. The battery according to any one of claims 1 to 11, characterized in that: The distance between the temperature protector (3) and the bottom end of the battery cell (1) is a set reserved distance, and the set reserved distance satisfies: D4≥5mm, and D4 is the set reserved distance.

13. The battery according to any one of claims 2 to 11, characterized in that The heating film (2) comprises a first insulating film (202) and a second insulating film (203) respectively attached and fixed to two sides of the heating core (201); the first insulating film (202) and the heating core (201) and the second insulating film (203) and the heating core (201) are bonded by thermally conductive adhesive.

14. The battery according to any one of claims 1 to 11, characterized in that: The heating area of ​​the heating film (2) and the large surface area of ​​the battery cell (1) satisfy the following relationship: Se:Sc=1:1, where Se is the heating area of ​​the heating film (2) and Sc is the large surface area of ​​the battery cell (1).

15. The battery according to any one of claims 1 to 11, characterized in that: The battery cell (1) comprises a first battery cell (11) and a second battery cell (12) which are arranged adjacent to each other; the heating film (2) is attached between the first battery cell (11) and the second battery cell (12); and the deep pit surface of the first battery cell (11) and the deep pit surfaces of the second battery cell (12) are opposite to each other.

16. A method for assembling a battery, characterized in that: Applied to the battery according to any one of claims 1 to 15, the steps comprising: Welding the first end of the wire to the first welding pad of the heating film; Welding the second end of the wire to the second pad of the protection plate; Adjust the positions of the first battery cell and the second battery cell until the deep pit surfaces of the two batteries face each other; Welding the tabs of both the first battery cell and the second battery cell to the connecting piece of the protection plate; The heating film is adhered between the first battery core and the second battery core.

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