A lithium-ion battery pack capable of operating in a low-temperature environment

Abstract

The present invention is a lithium-ion battery pack that can work in a low-temperature environment, belonging to the field of lithium-ion batteries. The technical solution adopted for the problem is as follows: a lithium-ion battery pack that can work in a low-temperature environment includes a battery body, a heating film and a BMS battery manager connected to the heating film. The heating film is surrounded by the side of the battery body and is used to heat the battery body. The BMS battery manager senses the temperature of the battery body through a temperature sensor located on one side of the battery body. The BMS battery manager turns on or off the heating film through the temperature signal detected by the temperature sensor. The heating film that plays a heating role is surrounded by the side of the battery body. The side area of ​​the battery body is large, and the heating is faster and more uniform, so that rapid heating is achieved. The heating film occupies a small space and is also very convenient to install. The BMS battery manager plays a role in monitoring and controlling the opening or closing of the heating film, which can keep the heating film in a stable heating temperature range.

Description

Technical Field

[0001] The invention belongs to the field of lithium ion batteries, and in particular relates to a lithium ion battery pack capable of operating in a low temperature environment. Background Art

[0002] At present, lithium-ion batteries have been widely used in various industries due to their advantages such as high voltage, large capacity, small size and light weight. In particular, they are widely used in the communications industry, especially as communications batteries. However, lithium-ion batteries are sensitive to the temperature of the use environment, especially when the charging and discharging efficiency is low below 0°C, so there are certain safety hazards in charging and discharging below 0°C. Lithium-ion battery packs used as communication batteries are usually used in outdoor environments, but when used in outdoor environments in winter, especially in northern outdoor environments, too low temperatures will cause low charging and discharging efficiency of lithium-ion battery packs, and eventually lead to the phenomenon that they cannot be charged after being discharged, resulting in internal damage to the lithium-ion battery pack and affecting the service life of the battery pack. Therefore, existing lithium-ion batteries cannot be used in low temperature environments. Summary of the invention

[0003] In view of the problem that existing lithium-ion battery packs are affected by low temperature and cannot be charged and discharged in a low temperature environment, the present invention provides a lithium-ion battery pack that can work in a low temperature environment, and a heating film is provided inside the lithium-ion battery pack to provide heat, so that the lithium-ion battery is not affected by low temperature and can be used in a low temperature environment.

[0004] The technical solution adopted by the present invention is as follows: a lithium-ion battery pack that can work in a low-temperature environment, including a battery body, a heating film and a BMS battery manager connected to the heating film, the heating film is surrounded by the side of the battery body and is used to heat the battery body, the BMS battery manager senses the temperature of the battery body through a temperature sensor located on one side of the battery body, and the BMS battery manager turns on or off the heating film through the temperature signal detected by the temperature sensor.

[0005] In this structure, the heating film that plays a heating role is surrounded by the side of the battery body. The side area of ​​the battery body is larger, and it is heated faster and more evenly, which can achieve rapid temperature rise. The heating film occupies a small space and is very convenient to install. The BMS battery manager monitors and controls the opening or closing of the heating film, which can keep the heating film within a stable heating temperature range, which can prevent the battery body from being damaged by excessive temperature and prevent the heating effect from being failed due to excessive temperature.

[0006] Furthermore, two battery soft pack cells are connected in series to form a battery cell group, and multiple battery cell groups are arranged side by side and connected in series to form the battery body. The heating film surrounds the outer side of the battery cell group and continuously passes between two adjacent battery cell groups. The heating film is wavy as a whole, so that one side of each battery cell group is in an open space. The heating film is wavy as a whole, with as many faces as possible close to the battery cell group to shorten the heating time.

[0007] Furthermore, there are multiple temperature sensors, and each battery cell group is provided with a temperature sensor on the side in an open state to prevent the temperature sensor from being heated by the heating film. The number of temperature sensors is consistent with the number of battery cell groups, so that the temperature data obtained by the BMS battery manager is more accurate, and the BMS battery manager can control the opening and closing of the heating film more accurately.

[0008] Furthermore, one end of the heating film is a power input end, on which a lead wire is provided, and the lead wire is connected to the power supply end of the BMS battery manager.

[0009] Furthermore, the heating film is a flexible PI heating film, and a backing adhesive is provided on the surface of one side thereof, so that the battery cell group is closely attached to the heating film to prevent the battery cell groups from being displaced from each other and facilitate the packaging of the battery cell group.

[0010] Furthermore, the thickness of the heating film is 0.2-0.4 mm, preferably 0.3 mm. The heating film has good temperature resistance, electrical insulation and radiation resistance, and can be used for a long time in the temperature range of -269~280°C; in addition, the heating film is soft, resistant to bending, heats up quickly, heats up evenly, consumes less power, is insulated and breathable, and has better adaptability.

[0011] Furthermore, the lithium-ion battery pack capable of operating in a low temperature environment further comprises an epoxy cover, which is a box-shaped structure with one end open, surrounding the outside of the battery body and the heating film, and accommodating the battery body and the heating film therein. The epoxy cover can protect the battery body and the heating film, and make the battery body as a whole, which can avoid a loose structure and facilitate handling. The epoxy cover also has a certain heat insulation and thermal insulation effect, effectively reducing heat loss.

[0012] Furthermore, the epoxy cover has a thickness of 0.4-0.6 mm, preferably 0.5 mm. If the epoxy cover is too thick, the molding is complicated, the weight is heavy and the cost is high. If the thickness is too small, the strength is insufficient and it is easy to break. The epoxy cover within this thickness range is light and strong enough to meet the use requirements.

[0013] Furthermore, the open end of the epoxy cover is provided with a PCB board, and the positive and negative electrodes of each battery soft pack monomer are connected to the PCB board through a connector respectively, and the positive and negative electrodes of two adjacent battery soft pack monomers are arranged in reverse and connected in sequence at the same connector, so that the connectors are arranged alternately on the PCB board to realize the series connection of adjacent battery soft pack monomers and the series connection of adjacent battery monomer groups. The battery soft pack monomer is fixed on the PCB board, and the position is relatively fixed, so as to ensure that the structure is not easy to loosen and the integrity is good.

[0014] Furthermore, the lithium-ion battery pack capable of operating in a low temperature environment further comprises a thermoplastic sleeve, which is arranged outside the epoxy cover and has a thickness of 0.4-0.6 mm, preferably 0.5 mm. Since the battery body, the heating film and the epoxy cover are connected to each other and are easily affected by external forces, the thermoplastic sleeve plays a protective role to prevent the battery body, the heating film and the epoxy cover from being worn and contaminated.

[0015] The present invention has the beneficial effects that the heating film for heating is surrounded by the side of the battery body, the side area of ​​the battery body is larger, the heat is faster and more uniform, and rapid temperature rise can be achieved, and the heating film occupies a small space and is very convenient to install; the BMS battery manager monitors and controls the opening or closing of the heating film, and can keep the heating film within a stable heating temperature range, which can avoid damage to the battery body due to excessively high temperature and prevent the heating effect from being failed due to excessively low temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of the structure of a lithium-ion battery pack capable of operating in a low temperature environment;

[0017] Figure 2 A schematic diagram of the connection structure of a lithium-ion battery pack that can work in a low-temperature environment;

[0018] Figure 3 A schematic diagram of the assembly structure of a lithium-ion battery pack that can work in a low-temperature environment;

[0019] Figure 4 It is a schematic diagram of the structure of the battery body;

[0020] In the figure: 1-battery body; 11-battery cell group; 111-battery soft pack cell; 2-heating film; 21-lead wire; 3-BMS battery manager; 31-temperature sensor; 4-epoxy cover; 5-PCB board; 51-connector; 6-thermoplastic sleeve. DETAILED DESCRIPTION

[0021] The following is an explanation and description of the technical solutions of the embodiments of the present invention in conjunction with the accompanying drawings of the present invention, but the following embodiments are only preferred embodiments of the present invention, not all. Based on the embodiments in the implementation mode, other embodiments obtained by those skilled in the art without creative work are all within the protection scope of the present invention.

[0022] The lithium-ion battery pack of this embodiment that can work in a low temperature environment is used as a 5G communication device, and its structure is as follows: Figures 1 to 4 As shown, it specifically includes a battery body 1, a heating film 2 and a BMS battery manager 3 connected to the heating film 2, the heating film 2 surrounds the side of the battery body 1, and is used to heat the battery body 1. The BMS battery manager 3 senses the temperature of the battery body 1 through a temperature sensor 31 located on one side of the battery body 1, and the BMS battery manager 3 turns on or off the heating film 2 through the temperature signal detected by the temperature sensor 31.

[0023] In this structure, the heating film 2 for heating is surrounded by the side of the battery body 1. The side area of ​​the battery body 1 is larger, and the heat is faster and more evenly, which can achieve rapid temperature rise. In addition, the heating film 2 occupies a small space and is very convenient to install. The BMS battery manager 3 monitors and controls the opening or closing of the heating film 2, so that the heating film 2 is within a stable heating temperature range, which can prevent the battery body 1 from being damaged by excessively high temperature and prevent the heating from being ineffective due to excessively low temperature.

[0024] Two battery soft pack monomers 111 are connected in series to form a battery monomer group 11, and multiple battery monomer groups 11 are arranged side by side to form the battery body 1. The heating film 2 surrounds the outer side of the battery monomer group 11 and continuously passes between two adjacent battery monomer groups 11. The heating film 2 is wavy as a whole, so that one side of each battery monomer group 11 is in an open space. The heating film 2 is wavy as a whole, and as many surfaces as possible are close to the battery monomer group 11 to shorten the heating time.

[0025] There are multiple temperature sensors 31, and each temperature sensor 31 is provided on the side of each battery cell group 11 in an open state to prevent the temperature sensor 31 from being heated by the heating film 2. The number of temperature sensors 31 is consistent with the number of battery cell groups 11, so that the temperature data obtained by the BMS battery manager 3 is more accurate, and the BMS battery manager 3 can control the opening and closing of the heating film 2 more accurately.

[0026] One end of the heating film 2 is a power input end, on which a lead wire 21 is provided. The lead wire 21 is connected to the power supply end of the BMS battery manager 3 .

[0027] The heating film 2 is a flexible PI heating film, and adhesive is provided on the surface of one side thereof, so that the battery cell group 11 is closely attached to the heating film 2 to prevent the battery cell groups 11 from shifting relative to each other and facilitate the packaging of the battery cell groups 11.

[0028] The thickness of the heating film 2 is 0.3mm. The heating film 2 has good temperature resistance, electrical insulation and radiation resistance, and can be used for a long time in the temperature range of -269~280℃; in addition, the heating film 2 is soft, resistant to bending, heats up quickly, heats up evenly, consumes less power, is insulated and breathable, and has better adaptability. The flexible PI heating film 2 used in this embodiment has a resistance of 58Ω and a voltage of 60V.

[0029] The lithium-ion battery pack capable of operating in a low temperature environment further comprises an epoxy cover 4, which is a box-shaped structure with one end open, surrounding the outside of the battery body 1 and the heating film 2, and accommodating the battery body 1 and the heating film 2. The epoxy cover 4 can protect the battery body 1 and the heating film 2, and make the battery body 1 as a whole, which can avoid a loose structure and facilitate transportation. The epoxy cover 4 also has a certain heat insulation and thermal insulation effect, effectively reducing heat loss.

[0030] The epoxy cover 4 has a thickness of 0.5 mm. If the epoxy cover 4 is too thick, the molding is complicated, the weight is large and the cost is high, while if the thickness is too small, the strength is insufficient and it is easy to break. The epoxy cover 4 within this thickness range is light and strong enough to meet the use requirements.

[0031] The open end of the epoxy cover 4 is provided with a PCB board 5, and the positive and negative electrodes of each battery soft pack monomer 111 are respectively connected to the PCB board 5 through a connector 51, and the positive and negative electrodes of two adjacent battery soft pack monomers 111 are arranged in reverse and connected in sequence at the same connector 51, so that the connectors 51 are arranged alternately on the PCB board 5 to achieve the series connection of adjacent battery soft pack monomers 111 and the series connection of adjacent battery monomer groups 11. In this embodiment, the connector 51 is formed by melting solder, and the battery soft pack monomer 111 is fixed on the PCB board 5, and the position is relatively fixed, which ensures that the structure is not easy to loosen and has good integrity.

[0032] The lithium-ion battery pack capable of operating in a low temperature environment further comprises a thermoplastic sleeve 6, which is arranged outside the epoxy cover 4 and has a thickness of 0.5 mm. Since the battery body 1, the heating film 2 and the epoxy cover 4 are connected to each other and are easily affected by external forces, the thermoplastic sleeve 6 plays a protective role to prevent the battery body 1, the heating film 2 and the epoxy cover 4 from being worn or contaminated.

[0033] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that the present invention includes but is not limited to the contents described in the drawings and the above specific embodiments. Any modification that does not deviate from the functional and structural principles of the present invention will be included in the scope of the claims.

Claims

1. A lithium-ion battery pack capable of operating in a low temperature environment, characterized in that: It includes a battery body, a heating film and a BMS battery manager connected to the heating film, wherein the heating film surrounds the side of the battery body and is used to heat the battery body, the BMS battery manager senses the temperature of the battery body through a temperature sensor located on one side of the battery body, and the BMS battery manager turns on or off the heating film through a temperature signal detected by the temperature sensor, two battery soft pack monomers are connected in series to form a battery monomer group, and a plurality of battery monomer groups are arranged side by side and connected in series to form the battery body, the heating film surrounds the outer side of the battery monomer group and continuously passes between two adjacent battery monomer groups, and the heating film is wavy as a whole, so that one side of each battery monomer group is in an open space; the lithium-ion battery pack that can work in a low-temperature environment also includes an epoxy cover, which is a box-shaped structure with an open end, which surrounds the outer side of the battery body and the heating film, and contains the battery body and the heating film therein; A PCB board is provided at the open end of the epoxy cover, and the positive and negative electrodes of each battery soft-pack monomer are respectively connected to the PCB board through a connector, and the positive and negative electrodes of two adjacent battery soft-pack monomers are arranged in reverse and connected in sequence at the same connector, so that the connectors are staggered on the PCB board to realize the series connection of adjacent battery soft-pack monomers and the series connection of adjacent battery monomer groups. One end of the heating film is a power input end, on which a lead wire is provided, and the lead wire is connected to the power supply end of the BMS battery manager. The heating film is a flexible PI heating film, and a backing glue is provided on the surface of one side thereof, so that the battery monomer group is close to the heating film.

2. The lithium-ion battery pack capable of operating in a low temperature environment according to claim 1, characterized in that: There are a plurality of temperature sensors, and a temperature sensor is provided on the side of each battery cell group in an open state.

3. The lithium-ion battery pack capable of operating in a low temperature environment according to claim 1, characterized in that: The thickness of the heating film is 0.2-0.4 mm.

4. The lithium-ion battery pack capable of operating in a low temperature environment according to claim 1, characterized in that: The epoxy cover has a thickness of 0.4-0.6 mm.

5. The lithium-ion battery pack capable of operating in a low temperature environment according to claim 1, characterized in that: It also includes a thermoplastic sleeve, which is arranged outside the epoxy cover and has a thickness of 0.4-0.6 mm.

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