Battery monomer, battery and electric device

Abstract

The utility model discloses a battery monomer which comprises a shell, a battery cell, a supporting plate and a guide pipe, and the shell comprises a bottom plate and a side plate connected with the bottom plate; the battery cell is positioned in the shell; the supporting plate is arranged between the bottom plate and the battery cell, the bottom plate, the side plates and the supporting plate form a liquid supplementing storage cavity used for containing electrolyte, and the supporting plate comprises a body part and a pressure sensing part; the pressure sensing part provides extrusion force for the electrolyte in the liquid supplementing storage cavity, and the electrolyte in the liquid supplementing storage cavity is conveyed into the battery cell through the guide pipe. Therefore, according to the single battery, the electrolyte is extruded and conveyed into the battery cell through the electrolyte liquid storage cavity, the guide pipe and the pressure sensing part capable of providing extrusion force for the electrolyte liquid in the electrolyte liquid storage cavity; the battery cell can be continuously supplemented with liquid through the conduit according to the pressure change in the battery monomer, and the problem of electrolyte deficiency in the later cycle period of the battery monomer can be solved.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium ion batteries, in particular to a battery monomer, a battery provided with the battery monomer and an electric device provided with the battery. Background Art

[0002] Lithium-ion battery cells are widely used in mobile electronic devices, electric vehicles, energy storage systems and other fields due to their high energy density, high voltage and many advantages of being relatively environmentally friendly. The cycle life of lithium-ion battery cells is an important indicator for evaluating their performance. Due to factors such as side reactions in the internal chemical system of the battery cells, lithium-ion battery cells will have a certain amount of electrolyte loss after a certain cycle, resulting in poor performance of the battery cells and decreased cycle performance. Therefore, it is necessary to replenish the internal lithium-ion battery cells to ensure the later cycle performance. The existing replenishment technology is excessive injection in the early stage, which has the problem of low initial efficiency due to excessive injection of electrolyte at one time. Utility Model Content

[0003] In view of this, the purpose of the present invention is to provide a battery cell, a battery and an electrical device, which can solve the problem of electrolyte loss in the late stage of battery cycle.

[0004] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0005] A battery cell, comprising:

[0006] A housing, comprising a bottom plate and side plates connected to the bottom plate;

[0007] A battery cell, located in the housing;

[0008] A support plate, the support plate is arranged between the bottom plate and the battery core, and the bottom plate, the side plate and the support plate constitute a liquid replenishment storage cavity for accommodating electrolyte, and the support plate includes a main body portion and a pressure sensing portion;

[0009] The pressure sensing part provides an extrusion force for the electrolyte in the liquid replenishment storage chamber, and the electrolyte in the liquid replenishment storage chamber is transported to the battery cell through the conduit.

[0010] Optionally, in the above-mentioned battery cell, the pressure sensing portion includes an elastic membrane, and the ratio of the area of ​​the elastic membrane to the area of ​​the support plate is 30% to 80%;

[0011] Optionally, in the above battery cell, the elastic membrane is located on both sides of the main body along the width direction of the battery cell;

[0012] And / or, the elastic membrane is located on both sides of the main body along the length direction of the battery core.

[0013] Optionally, in the above battery cell, the conduit comprises:

[0014] A first portion, extending along the height direction of the battery core, and located between the battery core and the side plate;

[0015] A second portion extending in a direction perpendicular to the height direction and located at the top of the battery cell;

[0016] The liquid replenishment storage chamber, the first part, and the second part are sequentially connected;

[0017] The cross-sectional area of ​​the first portion is greater than the cross-sectional area of ​​the second portion.

[0018] Optionally, in the above battery cell, a cross-sectional area of ​​the first portion gradually decreases from close to the bottom plate toward away from the bottom plate.

[0019] Optionally, in the above battery cell, the diameter of the first portion is 1 mm to 2 mm;

[0020] And / or, the diameter of the second portion is 0.5 mm to 1 mm.

[0021] Optionally, in the above battery cell, a dimension of the first portion protruding relative to the top of the battery cell in a height direction is 1 mm to 2 mm.

[0022] Optionally, in the above battery cell, the height of the liquid replenishment storage chamber is 3 mm to 5 mm.

[0023] A battery comprises the above-mentioned battery monomer.

[0024] An electrical device comprises the above-mentioned battery.

[0025] It can be seen from the above technical scheme that the battery cell of the utility model utilizes the side plate and the bottom plate of the support plate and the outer shell to form a fluid replenishment storage chamber for accommodating electrolyte, and at the same time, the pressure sensing part can provide extrusion force for the electrolyte in the fluid replenishment storage chamber, and squeeze the electrolyte into the battery cell through the conduit; the battery cell can be continuously replenished through the conduit according to the pressure change in the battery cell, which can not only solve the problem of electrolyte loss in the late stage of the battery cell cycle, but also avoid the problem of low initial efficiency caused by injecting too much electrolyte at one time. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 A schematic structural diagram of a battery cell provided in an embodiment of the utility model.

[0028] in:

[0029] 11-bottom plate, 12-side plate, 2-battery cells,

[0030] 3- support plate, 31- main body, 41- first part, 42- second part. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0032] In the description of the utility model, it should be noted that the terms "center", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the utility model product is usually placed when in use, and are only for the convenience of describing the utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the utility model. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0033] like Figure 1 As shown, an embodiment of the utility model provides a battery cell.

[0034] First, the battery cell includes an outer shell, a battery cell 2, a support plate 3 and a conduit, wherein the outer shell includes a bottom plate 11 and a side plate 12 connected to the bottom plate 11, the side plate 12 is arranged along the circumference of the bottom plate 11, wherein the circumference refers to the outer contour line of the bottom plate 11; the battery cell 2 is located in the outer shell; the support plate 3 is arranged between the bottom plate 11 and the battery cell 2, and the bottom plate 11, the side plate 12 and the support plate 3 constitute a fluid replenishment storage cavity for accommodating electrolyte, the support plate 3 includes a main body 31 and a pressure sensing portion, the pressure sensing portion provides extrusion force for the electrolyte in the fluid replenishment storage cavity, and transports the electrolyte in the fluid replenishment storage cavity to the battery cell 2 through the conduit. It should be noted that the outer wall of the fluid replenishment storage chamber is composed of the side plate 12, the bottom plate 11 and the support plate 3 of the outer shell, so as to make full use of the internal space of the outer shell; the support plate 3 is sealed and connected to the side plate 12 to avoid the presence of gaps at the connection, which may cause pressure to leak from the connection to the fluid replenishment storage chamber, affecting the replenishment of the electrolyte in the battery cell 2; at the same time, the conduit penetrates the support plate 3 and is sealed and connected to the support plate 3, which not only enables the conduit to be connected to the fluid replenishment storage chamber, but also avoids the presence of gaps at the connection, which may cause pressure to leak from the connection to the fluid replenishment storage chamber, affecting the replenishment of the electrolyte in the battery cell 2.

[0035] It can be seen that the battery cell provided in the embodiment of the utility model utilizes the support plate 3 and the side plate 12 and the bottom plate 11 of the outer shell to form a fluid replenishment storage chamber for accommodating electrolyte, and the pressure sensing part can provide extrusion force for the electrolyte in the fluid replenishment storage chamber, and squeeze the electrolyte into the battery cell 2 through the conduit; the battery cell 2 can be continuously replenished through the conduit according to the pressure change in the battery cell, which can not only solve the problem of electrolyte loss in the late stage of the battery cell cycle, but also avoid the problem of low initial efficiency caused by injecting too much electrolyte at one time.

[0036] In a specific implementation, the pressure sensing part includes an elastic membrane, wherein the ratio of the area of ​​the elastic membrane to the area of ​​the support plate 3 is 30% to 80%. It should be noted that the elastic membrane may be one, two or more, and the ratio of the area of ​​the elastic membrane to the area of ​​the support plate 3 refers to the ratio of the sum of the areas of all elastic membranes to the area of ​​the support plate 3. During the cycle of the battery cell, side reactions occur inside the battery cell. When the electrolyte is lost, a certain amount of gas is generated. The air pressure inside the battery cell increases, exerting a force on the elastic membrane. On the one hand, the elastic membrane expands under force to squeeze the electrolyte in the replenishment storage chamber, causing the electrolyte to flow through the conduit into the battery cell 2; on the other hand, the expansion of the elastic membrane releases space, which can play an explosion-proof role. When the battery cell is a square shell battery cell, the width direction of the battery cell is Figure 1 The x direction in the figure, the length direction of the battery cell is Figure 1y direction in the figure; when the battery cell is a cylindrical battery cell, the width direction of the battery cell is any direction parallel to the plane where the bottom plate 11 is located (that is, any direction parallel to the plane where the bottom plate 11 is located can be defined as the width direction), and its length direction is a direction parallel to the plane where the bottom plate 11 is located and perpendicular to the width direction.

[0037] In a specific implementation, the elastic membrane is located on both sides of the main body 31 along the width direction of the battery cell 2; and / or, the elastic membrane is located on both sides of the main body along the length direction of the battery cell. The elastic membrane is located on both sides, and the support plate in the middle can play a supporting role. It should be noted that the position of the elastic membrane is not limited to the two sides of the main body 31 along the width direction or length direction of the battery cell 2, as long as it can provide extrusion force for the electrolyte in the replenishment storage cavity and squeeze the electrolyte into the battery cell 2; and the main body can provide support for the battery cell. The specific number and position of the elastic membrane can be specifically designed by those skilled in the art according to actual needs.

[0038] In a specific implementation, the conduit includes a first portion 41 and a second portion 42, wherein the first portion 41 extends along the height direction of the battery cell 2 and is located between the battery cell 2 and the side plate 12; the second portion 42 extends along a direction perpendicular to the height direction and is located at the top of the battery cell 2. The height direction of the battery cell 2 is Figure 1 The z direction in the figure, but the first part 41 is not limited to the direction parallel to the height direction, as long as it extends in the height direction, it can also extend in the height direction at an angle, and the second part 42 extending in the direction perpendicular to the height direction is not strictly limited to extending in a certain direction within a plane perpendicular to the height direction, and there can also be an angle of upward or downward inclination, as long as the outlet of the second part 42 can be located at the top of the battery cell, so that the electrolyte can replenish the battery cell 2 from the top of the battery cell 2; the replenishment storage chamber, the first part 41, and the second part 42 are connected in sequence, so that the replenishment storage chamber can be connected to the first part 41 and the second part 42. The electrolyte in the storage cavity flows out from the rehydration storage cavity under the effect of the squeezing force, and reaches the battery cell 2 after passing through the first part 41 and the second part 42 in sequence, so as to replenish the electrolyte in the battery cell 2, and the rehydration from the top of the battery cell 2 allows the replenished electrolyte to fully infiltrate each position inside the battery cell 2, so that the rehydration is more uniform; the cross-sectional area of ​​the first part 41 is larger than the cross-sectional area of ​​the second part 42, so as to ensure that the pressure of the lower part of the conduit is greater than that of the upper part, and the electrolyte can only flow from the lower part of the conduit to the top to prevent the electrolyte from being sucked back. This structure ensures that the electrolyte in the rehydration storage cavity can replenish the battery cell 2 in the later stage of the cycle. The electrolyte outlet on the conduit is located at the top of the middle part of the battery cell 2, so as to facilitate the electrolyte to flow evenly to the inside of the battery cell 2, but it is not limited to this. The number and specific position of the conduit can be specifically designed by those skilled in the art according to actual needs. In addition, the cross-section of the first part is circular or elliptical but not limited to circular or elliptical; the cross-section of the second part is circular or elliptical but not limited to circular or elliptical.

[0039] In specific implementation, the cross-sectional area of ​​the first part 41 gradually decreases from the direction close to the bottom plate 11 to the direction away from the bottom plate 11. It can more effectively ensure that the pressure of the lower part of the conduit is greater than that of the upper part, and the electrolyte can only flow from the lower part to the top to prevent electrolyte backflow, ensuring that the electrolyte in the replenishment storage chamber can replenish the battery cell 2 in the later stage of the cycle. When the cross-section of the first part is circular, the diameter of the end of the first part 41 close to the bottom plate 11 can be 1.5mm, and the diameter of the end of the first part 41 away from the bottom plate 11 can be 1.1mm, but it is not limited to this. The diameter of the end of the first part 41 close to the bottom plate and the end away from the bottom plate can prevent electrolyte backflow and ensure that the electrolyte in the replenishment storage chamber can replenish the battery cell 2 in the later stage of the cycle. The specific diameter or cross-sectional area can be specifically designed by those skilled in the art according to actual needs.

[0040] In a specific implementation, the diameter of the first part 41 is 1 mm to 2 mm; and / or, the diameter of the second part 42 is 0.5 mm to 1 mm, but is not limited thereto. The diameters of the first part 41 and the second part 42 only need to ensure that the electrolyte can only flow from the bottom to the top to prevent the electrolyte from being sucked back. The specific values ​​of the diameters can be specifically designed by technical personnel in this field according to actual needs.

[0041] In specific implementation, the first portion 41 protrudes by 1 mm to 2 mm in height relative to the top of the battery cell 2, which facilitates the supply of electrolyte from the top of the battery cell 2 and ensures that the electrolyte can be injected from the top, and can fully and effectively supply the electrolyte in the liquid storage cavity to various parts of the battery cell 2, while avoiding the protrusion being too high, which will lead to a low energy density of the battery cell.

[0042] In specific implementation, the height of the liquid replenishment storage chamber is 3mm to 5mm, so that the elastic membrane has a certain elastic movement space, and at the same time, it ensures that the liquid replenishment storage chamber has enough space to store electrolyte, avoiding the problem of too large a space causing the energy density of the battery cell to be relatively low, and at the same time avoiding the problem of too little electrolyte in the liquid replenishment storage chamber causing the space to be too small, which cannot meet the problem of electrolyte shortage in the later stage of the battery cell cycle.

[0043] During specific implementation, during the operation of the battery cell, the electrolyte in the battery cell undergoes a side reaction to produce gas. The expansion of the gas causes the elastic membrane to be subjected to squeezing force, and the elastic membrane expands toward the side close to the bottom plate, thereby compressing the volume of the fluid replenishment storage chamber and squeezing out the electrolyte in the fluid replenishment storage chamber. The squeezed electrolyte is transported to the battery cell through a conduit connected to the fluid replenishment storage chamber.

[0044] The embodiment of the utility model provides a battery, comprising the above-mentioned battery monomer. It should be noted that the battery can be a battery module or a battery pack including the battery monomer.

[0045] It can be seen that the battery cell in the battery provided by the embodiment of the utility model utilizes the support plate 3 and the side plate 12 and the bottom plate 11 of the outer shell to form a liquid replenishment storage chamber for accommodating electrolyte, and the pressure sensing part can provide extrusion force for the electrolyte in the liquid replenishment storage chamber to squeeze the electrolyte into the battery cell 2; the battery cell 2 can be continuously replenished through the conduit according to the pressure change in the battery cell, which can not only solve the problem of electrolyte loss in the late stage of the battery cell cycle, but also avoid the problem of low initial efficiency caused by injecting too much electrolyte at one time.

[0046] An embodiment of the utility model provides an electrical device, comprising the above-mentioned battery.

[0047] The electrical device of the utility model is not particularly limited, and may include but is not limited to: laptop computers, pen-input computers, mobile computers, e-book players, portable phones, portable fax machines, portable copiers, portable printers, head-mounted stereo headphones, video recorders, LCD televisions, portable cleaners, portable CD players, mini CDs, transceivers, electronic notepads, calculators, memory cards, portable recorders, radios, backup power supplies, motors, cars, motorcycles, power-assisted bicycles, bicycles, lighting fixtures, toys, game consoles, clocks, power tools, flashlights, cameras, large household batteries and lithium-ion capacitors, etc.

[0048] According to the height of the fluid infusion storage chamber and the size of the catheter, the following examples and comparative ratios were made for data analysis:

[0049] Exemplary Embodiment 1

[0050] Embodiment 1 of the present invention provides a battery cell, wherein the height of the liquid replenishment storage chamber is 3 mm, the diameter of the first portion 41 of the conduit decreases from 1.5 mm to 1.1 mm, and the diameter of the second portion 42 is 1 mm.

[0051] In specific implementation, the first efficiency and cycle tests are carried out at a current density of 1C / 1C at a voltage window of 2.5-3.65V at 25±2℃. At the same time, a safety overcharge experiment is carried out: after charging the battery cell to 3.65V, continue charging at a constant current of 0.5C until the voltage reaches 1.5 times the battery cell charging termination voltage or the charging time reaches 1h, stop charging, and observe for 60 minutes to see if there is any fire or explosion.

[0052] Exemplary Embodiment 2

[0053] Embodiment 2 of the present invention provides a battery cell which is different from the above embodiment 1 in that:

[0054] In a specific implementation, the diameter of the first portion 41 of the catheter is 2 mm, and the diameter of the second portion 42 is 0.5 mm.

[0055] Exemplary Embodiment 3

[0056] Embodiment 3 of the present utility model provides a battery cell which is different from the above embodiment 1 in that:

[0057] In a specific implementation, the height of the fluid infusion storage chamber is 5 mm, and the diameter of the first portion 41 of the catheter is 1.5 mm.

[0058] Comparative Example 1

[0059] The utility model provides a battery cell in comparative example 1, which is different from the above-mentioned embodiment 1 in that:

[0060] There is no pressure sensing part on the support plate 3.

[0061] Comparative Example 2

[0062] Comparative Example 2 of the present invention provides a battery cell which is different from the above-mentioned Example 1 in that:

[0063] The diameter of the first portion 41 of the conduit is the same as the diameter of the second portion 42 .

[0064] Comparative Example 3

[0065] Comparative Example 3 of the present invention provides a battery cell which is different from Comparative Example 1 above in that:

[0066] Excessive electrolyte injection in the early stage.

[0067] The electrochemical performance tests were conducted on the battery cells of the embodiment and the comparative example, and the test results are shown in Table 1;

[0068] Table 1

[0069] Serial number Safety test results First results 25℃1C / 1C cycle results Example 1 No fire, no explosion 96.5％ 2000 laps 87.2% SOH Example 2 No fire, no explosion 96.4％ 2000 laps 87.1% SOH Example 3 No fire, no explosion 96.4％ 2000 laps 87.3% SOH Comparative Example 1 No fire, explosion-proof valve ruptured 96.4％ 2000 laps 72.3% SOH Comparative Example 2 No fire, no explosion 96.5％ 2000 cycles 72.9% SOH Comparative Example 3 No fire, explosion-proof valve ruptured 92.8％ 2000 laps 83.2% SOH

[0070] It can be seen from Table 1 that the elastic membrane is explosion-proof and injecting an appropriate amount of electrolyte can avoid the problem of low initial efficiency caused by injecting too much electrolyte at one time.

[0071] Furthermore, the diameter of the first portion 41 of the conduit is greater than the diameter of the second portion 42, and the diameter of the first portion 41 gradually decreases from close to the bottom plate 11 to away from the bottom plate 11, which can make the pressure in the lower part of the conduit greater than the pressure in the upper part, and can play an anti-backflow role, so that the electrolyte can be transported from the liquid replenishment storage chamber to the battery cell 2, and the circulation effect is good.

[0072] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0073] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0074] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A battery cell, characterized in that: include: A housing comprising a bottom plate (11) and a side plate (12) connected to the bottom plate (11); A battery cell (2), located in the housing; A support plate (3), the support plate (3) being arranged between the bottom plate (11) and the battery core (2), and the bottom plate (11), the side plate (12) and the support plate (3) forming a liquid replenishment storage cavity for accommodating electrolyte, and the support plate (3) comprising a main body portion (31) and a pressure sensing portion; The pressure sensing part provides a squeezing force for the electrolyte in the liquid replenishment storage chamber, and the electrolyte in the liquid replenishment storage chamber is transported to the battery core (2) through the catheter.

2. The battery cell according to claim 1, characterized in that: The pressure sensing part comprises an elastic membrane, and the ratio of the area of ​​the elastic membrane to the area of ​​the support plate (3) is 30% to 80%.

3. The battery cell according to claim 2, characterized in that: The elastic membrane is located on both sides of the main body (31) along the width direction of the battery core (2); And / or, the elastic membrane is located on both sides of the main body (31) along the length direction of the battery core (2).

4. The battery cell according to claim 1, characterized in that: The catheter comprises: A first portion (41) extends along the height direction of the battery core (2) and is located between the battery core (2) and the side plate (12); A second portion (42) extending in a direction perpendicular to the height direction and located at the top of the battery cell (2); The liquid replenishment storage chamber, the first part (41), and the second part (42) are connected in sequence; The cross-sectional area of ​​the first portion (41) is greater than the cross-sectional area of ​​the second portion (42).

5. The battery cell according to claim 4, characterized in that: The cross-sectional area of ​​the first portion (41) gradually decreases from a direction close to the bottom plate (11) to a direction away from the bottom plate (11).

6. The battery cell according to claim 4, characterized in that: The diameter of the first part (41) is 1 mm to 2 mm; And / or, the diameter of the second portion (42) is 0.5 mm to 1 mm.

7. The battery cell according to claim 4, characterized in that: The first portion (41) protrudes by 1 mm to 2 mm in height relative to the top of the battery core (2).

8. The battery cell according to claim 1, characterized in that: The height of the fluid replenishment storage chamber is 3 mm to 5 mm.

9. A battery, characterized in that: A battery cell comprising any one of claims 1 to 8.

10. An electrical device, characterized in that: A battery comprising the battery of claim 9.

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