High-capacity battery

Abstract

The utility model provides a high-capacity battery, which mainly solves the safety and performance problems caused by the increase or decrease of the internal pressure of the existing high-capacity battery. The high-capacity battery comprises a shell and a plurality of single batteries arranged in the shell along the same direction, a gas sharing chamber is arranged in the shell, and an inner cavity of the gas sharing chamber is communicated with all the single battery gas areas; an air pressure balancing device is arranged in the air sharing chamber, the air pressure balancing device enables the air pressure of the air sharing chamber and the air pressure of the external environment to tend to be balanced, and the problems of shell expansion or shell sealing position leakage and the like caused by air pressure rise in the air sharing chamber are solved; and the problem that the performance of the high-capacity battery is influenced by the reduction or rise of the air pressure in the air sharing chamber is also avoided, so that the performance and the safety of the high-capacity battery are improved.

Description

Technical Field

[0001] The utility model belongs to the field of batteries, and in particular relates to a large-capacity battery. Background Art

[0002] Lithium-ion batteries have many advantages, such as high packaging reliability, high energy efficiency, simple structure, and relatively convenient expansion. Multiple lithium-ion batteries can be connected in parallel to form a large-capacity battery, and then the large-capacity batteries can be used in series and parallel in energy storage, power batteries and other fields. However, after lithium-ion batteries are connected in parallel to form a large-capacity battery, it is necessary to ensure that they have stable electrical performance and high safety.

[0003] When large-capacity batteries are stored, charged and discharged in high and low temperature environments, the internal air pressure will increase or decrease. The increase in internal pressure will cause a series of safety problems such as battery shell expansion and leakage at the battery shell seal. At the same time, the increase or decrease in internal pressure will also affect the performance of large-capacity batteries. Summary of the invention

[0004] The utility model provides a large-capacity battery, which mainly solves the safety and performance problems existing in the existing large-capacity battery due to the increase or decrease of the internal pressure.

[0005] In order to solve the above problems, the technical solution provided by the utility model is:

[0006] A large-capacity battery comprises an outer shell and a plurality of single cells arranged in the outer shell in the same direction; a gas sharing chamber is arranged in the outer shell, and the inner cavity of the gas sharing chamber is connected to the gas areas of all the single cells; the battery is special in that it also comprises an air pressure balancing device, the outer shell has a through hole, and the air pressure balancing device is arranged in the gas sharing chamber through the through hole, so that the air pressure in the gas sharing chamber tends to be balanced with the air pressure of the external environment.

[0007] Furthermore, the air pressure balancing device includes a balancing sleeve arranged in the gas sharing chamber and a balancing piston arranged in the balancing sleeve; the end of the balancing sleeve is connected to the through hole so that one end of the balancing sleeve is connected to the inner cavity of the gas sharing chamber, and the other end is connected to the external environment; the balancing piston can seal the inner cavity of the balancing sleeve, and the balancing piston can move in the balancing sleeve so that the air pressure in the gas sharing chamber tends to balance the air pressure of the external environment.

[0008] Furthermore, limiting portions are provided at both ends of the inner cavity of the balancing sleeve so that the balancing piston is always located in the inner cavity of the balancing sleeve.

[0009] Furthermore, the balancing piston is a cylindrical sealing plug, and the outer wall of the balancing piston is provided with at least one circumferential annular sealing groove, and an annular sealing ring is provided in the annular sealing groove.

[0010] Furthermore, a positioning boss is provided at the end of the balancing sleeve connected to the through hole, and a positioning groove is provided on the outer shell, and the positioning boss of the balancing sleeve is embedded in the positioning groove of the outer shell.

[0011] Furthermore, avoidance holes are provided on the top plate of the shell corresponding to the polarity terminals of each single cell; the polarity terminals of each single cell extend out of the avoidance holes, and the top plate area of ​​the shell corresponding to the avoidance holes is fixedly sealed with the shell of the single cell; an electrolyte sharing chamber is also provided in the shell, and the inner cavity of the electrolyte sharing chamber is connected to the electrolyte areas of all single cells.

[0012] Furthermore, a clamping portion is provided at the portion where each single cell polarity terminal extends out of the avoidance hole, a heat transfer tube is fixed on the clamping portion of each single cell polarity terminal, and the heat transfer tube is insulated from each single cell polarity terminal, and the clamping portion is a through groove or through hole opened on each single cell polarity terminal.

[0013] Furthermore, the heat transfer tube is a metal tube, and the metal tube has at least one of an insulating layer and an insulating sleeve.

[0014] Furthermore, an insulating sealant layer is laid on the top plate of the shell, and the liquid inlet end and the liquid outlet end of the heat transfer tube extend out of the insulating sealant layer.

[0015] Furthermore, an insulating protective cover is provided on the top of the shell, and polarity terminals of each single battery are located inside the insulating protective cover.

[0016] Compared with the prior art, the beneficial effects of the technical solution of the utility model are:

[0017] 1. In the large-capacity battery of the utility model, multiple single cells are placed in a shell with a gas-sharing chamber, thereby improving the overall number of cycles, upper capacity limit and service life of the large-capacity battery. At the same time, a gas pressure balancing device is added to the gas-sharing chamber of the above-mentioned shell, and the gas pressure balancing device makes the gas pressure in the gas-sharing chamber tend to balance with the external environmental pressure, avoiding the expansion of the shell or leakage of the shell seal caused by the increase of the gas pressure in the gas-sharing chamber. At the same time, it also avoids the problem that the increase or decrease of the gas pressure in the gas-sharing chamber affects the performance of the large-capacity battery in a high or low temperature environment, and the performance and safety of the large-capacity battery are improved.

[0018] 2. In the large-capacity battery of the utility model, the air pressure balancing device includes a balancing sleeve arranged in the gas sharing chamber and a balancing piston arranged in the balancing sleeve. The air pressure balancing device of this structure is simple in structure and easy to install.

[0019] 3. In the large-capacity battery of the utility model, limiting parts are set at both ends of the inner cavity of the balancing sleeve, so that the balancing piston is always located in the inner cavity of the balancing sleeve and will not be squeezed out of the balancing sleeve, so that the explosion venting part of the large-capacity battery can be normally vented. At the same time, a positioning boss is provided on the balancing sleeve, and a positioning groove is provided on the outer shell. The positioning boss of the balancing sleeve is embedded in the positioning groove of the outer shell, so that the balancing sleeve and the outer shell can be accurately and reliably installed.

[0020] 4. In the large-capacity battery of the utility model, an electrolyte sharing chamber is also provided in the outer shell, and the inner cavity of the electrolyte sharing chamber is connected to the electrolyte of all the single cells, so that the electrolyte and gas of each single cell are shared to ensure the consistency of each single cell, reduce the difference between the electrolyte and gas of each single cell, improve the consistency between each single cell to a certain extent, thereby improving the cycle life of the large-capacity battery.

[0021] 5. In the large-capacity battery of the utility model, a clamping part is provided at the polarity terminal of each single cell, and the heat transfer tube is fixed by the clamping part, so that the heat transfer tube is in direct contact with the polarity terminal of the single cell, and the heat of the polarity terminal where the heat is most concentrated is transferred to the outside for processing. This heat dissipation method realizes balanced heat dissipation of the top of the large-capacity battery, especially the polarity terminal, and avoids performance problems and safety problems caused by excessively high or low temperature of the large-capacity battery.

[0022] 6. In the large-capacity battery of the utility model, the clamping part is a through groove or through hole opened on the polarity terminal of each single battery, and the heat transfer tube is arranged in the through groove or through hole, and directly contacts with the polarity terminal of each single battery, so that the heat transfer tube and the polarity terminal have a larger contact area, further improving the heat exchange efficiency.

[0023] 7. In the large-capacity battery of the utility model, an insulating layer and an insulating sleeve are provided on the heat transfer tube, so that when the heat transfer tube exchanges heat with each single battery, reliable insulation performance can be maintained, thereby improving the safety of the heat transfer tube and the large-capacity battery during use.

[0024] 8. In the large-capacity battery of the utility model, an insulating sealant layer is laid on the top plate of the shell. When condensation occurs on the surface of the heat transfer tube on the polarity terminal, the condensation cannot penetrate into the gap between the polarity terminal and the avoidance hole due to the blocking of the insulating sealant layer, thereby preventing the battery from short-circuiting.

[0025] 9. In the large-capacity battery of the utility model, an insulating protective cover is used to provide insulation protection for the polarity terminals, thereby avoiding the potential safety hazards of the polarity terminals being exposed during the operation of the large-capacity battery, and also avoiding the problem of some foreign objects in the external environment falling into the polarity terminal position causing a short circuit in the large-capacity battery, thereby improving the safety of the large-capacity battery.

[0026] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through research and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic diagram of the structure of a large-capacity battery in Example 1;

[0028] Figure 2 This is a schematic diagram of the structure of a large-capacity battery in Example 1 (the front cover of the housing is omitted);

[0029] Figure 3 An exploded view of a large-capacity battery in Example 1;

[0030] Figure 4 is a cross-sectional view of a large-capacity battery in Example 1;

[0031] Figure 5 Schematic diagram of the structure of the air pressure balance device in Example 1;

[0032] Figure 6 This is a schematic diagram of the structure of a large-capacity battery in Example 2;

[0033] Figure 7 This is a schematic diagram of the structure of a large-capacity battery (with an insulating sealant layer) in Example 3;

[0034] Figure 8 Schematic diagram of the structure of a large-capacity battery (with an insulating protective cover) in Example 3.

[0035] Figure markings: 1-large capacity battery, 2-air pressure balancing device, 3-heat transfer tube, 11-housing, 12-single battery, 13-polarity terminal, 14-insulating sealant layer, 15-insulating protective cover, 16-support, 17-first electrical connector, 18-second electrical connector, 19-explosion relief part, 111-gas sharing chamber, 112-electrolyte sharing chamber, 113-avoidance hole, 114-through hole, 131-clamping part, 21-balancing sleeve, 22-balancing piston, 23-annular sealing ring, 24-limiting part, 211-positioning boss, 31-first tube, 32-second tube, 33-connecting tube. DETAILED DESCRIPTION

[0036] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the utility model, but not all of them. Based on the embodiments of the utility model, all other embodiments obtained by ordinary persons in the field without creative work should fall within the scope of protection of the utility model.

[0037] The "other embodiments" that appear in different places in this specification do not all refer to the same embodiment, nor are they separate or selective embodiments that are mutually exclusive with other embodiments. In the description of this specification, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. In the description of this utility model, the meaning of "multiple" is two or more, unless otherwise clearly and specifically limited.

[0038] In the description of this specification, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, an indirect connection through an intermediate, or the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.

[0039] At the same time, in the description of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "top, bottom, inside and outside" are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention 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 present invention.

[0040] Example 1

[0041] like Figure 1 and Figure 2 As shown, the large-capacity battery 1 in this embodiment includes a shell 11 and a plurality of single cells 12 arranged in the same direction and placed in the shell 11. The single cells 12 in this embodiment are square shell batteries, and the number can be adjusted according to actual needs. The inner cavity of each single cell 12 includes an electrolyte area and a gas area. After the multiple single cells 12 are arranged in the same direction and placed in the shell 11, avoidance holes 113 are opened on the top plate of the shell 11 corresponding to the polarity terminals 13 of each single cell 12, and the polarity terminals 13 of each single cell 12 extend out of the corresponding avoidance holes 113 as the polarity terminals of the large-capacity battery 1 (the polarity terminals of all single cells 12 on one side serve as the positive polarity terminals of the large-capacity battery 1, and the polarity terminals of all single cells 12 on the other side serve as the negative polarity terminals of the large-capacity battery 1), and the top plate area of ​​the shell 11 corresponding to the avoidance hole 113 is fixedly sealed with the shell of the single cell 12.

[0042] It should be noted that the polarity terminal 13 of the single cell 12 here can be the pole of the single cell 12. In order to avoid the pole of the single cell 12 from being unable to smoothly extend out of the avoidance hole 113 as a polarity terminal, a pole adapter can also be connected to the pole of the single cell 12, and the overall structure of the pole of the single cell 12 and the pole adapter can be used as the polarity terminal 13 of the single cell 12.

[0043] like Figure 2 As shown, a gas sharing chamber 111 is provided on the shell 11, and the inner cavity of the gas sharing chamber 111 is connected to the inner gas areas of all the single cells 12. The gas balance of each single cell 12 is achieved through the gas sharing chamber 111, thereby improving the performance and charge and discharge cycle life of the large-capacity battery 1.

[0044] like Figure 2 As shown, in other embodiments, the above-mentioned shell is also provided with an electrolyte sharing chamber 112, and the inner cavity of the electrolyte sharing chamber 112 is connected to the electrolyte areas of all single cells 12. Through the electrolyte sharing chamber 112, each single cell 12 can be placed in a unified electrolyte environment, thereby ensuring the uniformity of the electrolyte of each single cell 12 and improving the performance and charge and discharge cycle life of the large-capacity battery 1.

[0045] The housing 11 provided with the gas sharing chamber 111 and the electrolyte sharing chamber 112 may specifically adopt the following structure:

[0046] 1) The outer shell includes an outer cylinder, an upper cover, and a lower cover; the top and bottom of the outer cylinder are open, the upper cover is sealed and fixed (welded) to the top of the outer cylinder, and a evacuation hole is provided on the upper cover to allow each single battery pole to extend out, and the lower cover is sealed and fixed (welded) to the bottom of the outer cylinder. At the same time, the upper cover is provided with a protrusion extending along the arrangement direction of the single battery, and a gas sharing chamber is formed at the protrusion. The lower cover is provided with a protrusion extending along the arrangement direction of the single battery, and an electrolyte sharing chamber is formed at the protrusion.

[0047] 2) The housing includes a U-shaped housing, a first cover plate, a third cover plate and a second cover plate; the first cover plate and the third cover plate respectively cover the two opposite open ends of the U-shaped housing; the second cover plate covers the open end at the top of the U-shaped housing and is sealed with the open end, and a evacuation hole is provided on the second cover plate to allow each single cell pole to extend out, and at the same time, a protrusion extending along the arrangement direction of the single cells is provided on the second cover plate, and a gas sharing chamber is formed at the protrusion portion, and an electrolyte sharing chamber is provided at the bottom of the U-shaped housing, and the electrolyte sharing chamber is a liquid channel provided between the housing bottom plate and each single cell;

[0048] 3) If Figure 2 and Figure 3As shown, the outer shell 11 includes an outer cylinder, a front cover and a rear cover; the front and rear parts of the outer cylinder are open, the front cover is sealed and fixed (welded) to the front part of the outer cylinder, and the rear cover is sealed and fixed (welded) to the rear part of the outer cylinder. The top of the outer cylinder is provided with an avoidance hole 113 that allows the poles of each single battery 12 to extend out. The top of the outer cylinder is provided with a protrusion extending along the arrangement direction of the single battery 12, and a gas sharing chamber is formed at the protrusion. The bottom of the outer cylinder is provided with an electrolyte sharing chamber 112, and the electrolyte sharing chamber 112 is a liquid channel arranged between the support 16 in the outer cylinder and each single battery 12.

[0049] from Figure 2 It can be seen that the left and right ends of the outer cylinder of this structure are open and can be integrally formed by aluminum extrusion process. The bottom support member 16 is fixed in the outer cylinder, and the bottom support member 16 mainly has the following two functions: 1) to raise each single battery 12 so that the polarity terminal 13 of each single battery 12 extends out of the avoidance hole 113 of the top plate of the shell; 2) to support each single battery 12 and form a liquid channel between the bottom of each single battery 12 as an electrolyte shared chamber 113.

[0050] Since the gas areas of the individual cells 12 constituting the large-capacity battery 1 are interconnected, if a certain individual cell 12 produces more gas, then these excess gases will be connected and exchanged with the gases at the tops of other individual cells 12, so that the gas environments inside the individual cells 12 are more similar, forming a shared gas area, so that the individual cells 12 are in a balanced gas environment, and a gas difference environment will not be formed because a certain individual cell 12 produces more gas, thereby avoiding the influence of the differences in the individual cells 12 on the large-capacity battery 1.

[0051] For the large-capacity battery 1, as the number of charge and discharge cycles increases during use, the electrolyte continues to slowly generate gas. The characteristics of this gas are that the amount generated is small and the generation time is very long, even throughout the entire service life of the large-capacity battery 1. The gas gradually accumulates, causing the pressure in the gas sharing chamber 111 to increase. As the internal pressure of the gas sharing chamber 111 continues to increase, the shell 11 will expand, resulting in a decrease in the performance of the large-capacity battery 1. In addition, the temperature of the large-capacity battery 1 changes greatly during charging and discharging, and the temperature difference is about 10 to 30°C. If the large-capacity battery 1 is abnormally charged and discharged, the temperature difference will change even more. The temperature difference caused by frequent charging and discharging will cause the pressure cycle inside the gas sharing chamber 111 to increase or decrease, and the change in internal pressure will affect the performance of the large-capacity battery. At the same time, the increase and decrease of the gas pressure in the gas sharing chamber 111 are repeated many times, which will cause metal fatigue of the welding point and cause leakage at the seal of the shell 11.

[0052] Based on this, Figure 1 , Figure 3 and Figure 4 As shown, in this embodiment, a gas pressure balancing device 2 is provided in the gas sharing chamber 111 of the above-mentioned large-capacity battery, so that the gas pressure of the gas sharing chamber 111 tends to be balanced with the air pressure of the external environment, thereby avoiding the above-mentioned problems. It should be explained that the above-mentioned external environment refers to the external environment relative to the gas sharing chamber 111, for example, the use environment, working environment, etc. of the large-capacity battery 1. Since the air pressure in the external environment is relatively stable, the air pressure balancing device 2 maintains the air pressure in the gas sharing chamber 111 at a stable value, thereby avoiding the problems caused by the increase or decrease of the air pressure in the gas sharing chamber 111.

[0053] The number of the above-mentioned air pressure balance device 2 is at least one, and the specific number is set according to the needs. When the air pressure balance device 2 is installed, the shell 11 is provided with a through hole 114 connected to the gas sharing chamber 111, and the air pressure balance device 2 is installed in the gas sharing chamber 111 through the through hole 114. The air pressure balance device 2 can be implemented in the following structure:

[0054] First, the air pressure balancing device is a retractable bellows, which is a tubular structure with one end open and the other end closed. The open end of the bellows is sealed and connected to the through hole 114 on the housing 11, so that the inner cavity of the bellows is connected to the external environment. By adjusting the length of the bellows, the air pressure in the gas sharing chamber 111 tends to be balanced with the air pressure of the external environment.

[0055] Second, if Figure 4 and Figure 5 As shown, the air pressure balancing device 2 includes a balancing sleeve 21 disposed in the gas sharing chamber 111 and a balancing piston 22 disposed in the balancing sleeve 21; the end of the balancing sleeve 21 is sealed and connected to the through hole 114, so that one end of the balancing sleeve 21 is connected to the gas sharing chamber 111 in the housing 11, and the other end is connected to the external environment; the balancing piston 22 is disposed in the balancing sleeve 21, sealing the inner cavity of the balancing sleeve 21, and can also move in the balancing sleeve 21, so that the air pressure in the gas sharing chamber 111 tends to balance with the air pressure of the external environment. The air pressure balancing device 2 of this structure is simple in structure and easy to install.

[0056] The above-mentioned balancing piston 22 is preferably a cylindrical sealing plug, so that the balancing piston 22 can slide in the balancing sleeve 21. At the same time, the balancing piston 22 is made of metal, and has at least one circumferential annular sealing groove on its outer wall, and an annular sealing ring 23 is provided in the annular sealing groove, so that the balancing piston 22 can reliably seal the inner cavity of the balancing sleeve 21. In other embodiments, the entire balancing piston 22 can also be made of rubber and used as a sealing plug as a whole, but the service life of this structure is relatively short.

[0057] like Figure 5As shown, the balancing sleeve 21 is also provided with a positioning boss 211, and the housing 11 is provided with a positioning groove. The positioning boss 211 of the balancing sleeve 21 is embedded in the positioning groove of the housing 11, so that the balancing sleeve 21 and the housing 11 can be accurately and reliably positioned and installed. After the positioning boss 211 of the balancing sleeve 21 is embedded in the positioning groove of the housing 11, the balancing sleeve 21 and the housing 11 are fixedly connected, and the connection method includes but is not limited to welding, gluing, and threaded connection. Regardless of the connection method, the sealing of the connection must be ensured.

[0058] The above-mentioned balancing sleeve 21 is installed in the gas sharing chamber 111 of the large-capacity battery 1. The position of the balancing piston 22 in the balancing sleeve 21 moves with the change of the air pressure in the gas sharing chamber 111. When the air pressure in the gas sharing chamber 111 is consistent with that in the external environment, the balancing piston 22 is approximately in the middle position of the inner cavity of the balancing sleeve 21. At this time, when the air pressure in the gas sharing chamber 111 is greater than the air pressure in the external environment, the gas in the gas sharing chamber 111 pushes the balancing piston 22 to move outward in the balancing sleeve 21 until the air pressure in the gas sharing chamber 111 is consistent with that in the external environment. When the air pressure in the gas sharing chamber 111 is less than the air pressure in the external environment, the gas in the external environment pushes the balancing piston 22 to move inward in the balancing sleeve 21 until the air pressure in the gas sharing chamber 111 is consistent with that in the external environment. Since the air pressure in the external environment is relatively stable, the air pressure balancing device 2 maintains the air pressure in the gas sharing chamber 111 at a stable value, thereby avoiding the problems caused by the increase or decrease of the air pressure in the gas sharing chamber 111.

[0059] It should be noted that the limit pressure at which the air pressure balance device 2 is opened is greater than the opening pressure of the explosion relief part 19 of the large-capacity battery 1, that is, when the explosion relief part 19 of the large-capacity battery 1 is opened, the closed end of the bellows and the connection between the bellows and the shell 11 will not rupture or leak. Alternatively, when the explosion relief part 19 of the large-capacity battery 1 is opened, the connection between the balance sleeve 21 and the shell 11 will not rupture or leak, and at the same time, the balance piston 22 is always in the balance sleeve 21 and will not be squeezed out of the balance sleeve 21.

[0060] Based on this, the structure of the air pressure balancing device 2 is optimized, and a limit portion 24 is provided at both ends of the inner cavity of the balancing sleeve 21, so that the balancing piston 22 always moves in the balancing sleeve 21 and will not be squeezed out of the balancing sleeve 21. The limit portion 24 can be an annular boss fixed on the inner wall of the balancing sleeve 21, or a block boss fixed on the inner wall of the balancing sleeve 21. There is no requirement for its shape, as long as it can limit the balancing piston 22 in the balancing sleeve 21. During specific installation, the balancing piston 22 is first installed in the balancing sleeve 21, and then the limit portion 24 is fixed on the inner wall of the balancing sleeve 21.

[0061] After the large-capacity battery 1 in this embodiment is installed with the above-mentioned air pressure balancing device 2, when the large-capacity battery 1 is charged and discharged or the temperature changes, causing the internal pressure of the gas sharing chamber 111 to change, the balancing piston 22 moves in the balancing sleeve 21 to offset the internal and external pressure difference of the gas sharing chamber 111 of the large-capacity battery 1, thereby avoiding bulging or leakage caused by the change of the internal pressure of the gas sharing chamber 111 of the large-capacity battery 1, and improving the service life of the large-capacity battery 1.

[0062] In addition, in this embodiment, the air pressure balancing device 2 is arranged in the gas sharing chamber 111. During the process of balancing the air pressure by the air pressure balancing device 2, the outer shell 11 of the large-capacity battery 1 does not change, and there is no need to increase the space for the volume change of the large-capacity battery 1. It will not affect the assembly relationship of the large-capacity battery 1, which facilitates the installation and use of the large-capacity battery.

[0063] Example 2

[0064] like Figure 6 As shown, in this embodiment, a heat transfer tube 3 is added to the large-capacity battery of embodiment 1, so that the large-capacity battery 1 can work safely and reliably, avoiding performance problems and safety problems caused by excessively high or low temperature of the large-capacity battery.

[0065] The heat transfer tube 3 is installed on the polarity terminal 13 of the large-capacity battery 1, and is mainly used to control the temperature of the top of the large-capacity battery 1, especially the polarity terminal 13 of the large-capacity battery 1, to ensure that the large-capacity battery 1 operates within the optimal temperature range. Figure 2 As shown, a clamping part 131 is provided on the polarity terminal 13 of the large-capacity battery 1, and the heat transfer tube 3 is fixed in the clamping part 131, so that the heat transfer tube 3 is directly connected to the polarity terminal 13 of the large-capacity battery 1, and the heat on the polarity terminal 13 where the heat is relatively concentrated is promptly discharged, thereby improving the heat dissipation effect on the top of the large-capacity battery 1. In addition, when the temperature of the large-capacity battery 1 is lower than the set threshold, a heat transfer medium with a higher temperature is introduced into the heat transfer tube 3 to increase the temperature of the large-capacity battery 1; by controlling the temperature of the heat transfer medium, it can be ensured that the large-capacity battery 1 always operates at a normal operating temperature.

[0066] The heat transfer tube 3 is a pipe with a heat exchange function. There is no requirement for the cross-sectional shape of the heat transfer tube 3 as long as it can contact the polarity terminal 13 of the single battery 12 for heat exchange. For example, a square tube, an elliptical tube, a round tube, etc. can be used. In this embodiment, the heat transfer tube 3 is preferably a round tube, which is easy to install and can be made of existing metal tubes, with relatively low cost.

[0067] The heat transfer tube 3 in this embodiment specifically adopts a metal tube with good thermal conductivity, such as an aluminum tube, a copper tube, etc. Preferably, the heat transfer tube 3 adopts an aluminum tube with good thermal conductivity and relatively low cost. In order to ensure the thermal conductivity, the thinner the wall thickness of the aluminum tube, the better. However, if the wall thickness of the aluminum tube is too thin, the aluminum tube is relatively soft and is easy to bend and break during installation. Therefore, in this embodiment, the wall thickness of the aluminum tube is preferably 0.5mm to 1.5mm. The aluminum tube with this wall thickness can maintain its installation reliability while having good thermal conductivity, avoiding the risk of easy bending and damage when the wall thickness of the aluminum tube is thin. In specific use, the diameter of the aluminum tube is generally about 10mm to 20mm.

[0068] The above heat transfer tube 3 can be manufactured by adopting the following structure:

[0069] First, the heat transfer tube 3 can be made of a whole tube, and the whole aluminum tube is bent into a U-shaped tube, and the two straight tubes of the U-shaped tube are respectively fixed to the positive terminal and the negative terminal of each single battery 12 in the large-capacity battery 1;

[0070] Second, in order to facilitate installation, such as Figure 6 As shown, the heat transfer pipe 3 is a spliced ​​pipe, mainly including a first pipe 31, a second pipe 32 and a connecting pipe 33; the first pipe 31 is fixed on the clamping part 131 of the positive terminal of each single battery 12 in the large-capacity battery 1; the second pipe 32 is fixed on the clamping part 131 of the negative terminal of each single battery 12 in the large-capacity battery 1, and the two ends of the connecting pipe 33 are respectively connected to the ports of the first pipe 31 and the second pipe 32 located on the same side.

[0071] When the heat transfer tube 3 is matched with the polarity terminal 13 of the large-capacity battery 1, in order to ensure safety, the heat transfer tube 3 and the large-capacity battery 1 need to be insulated. Specifically, the insulation treatment can be achieved in the following ways: the heat transfer tube 3 is an insulating pipe made of insulating material, such as a plastic pipe or a ceramic pipe, etc. However, the thermal conductivity of metal pipes, plastic pipes or ceramic pipes is relatively poor. Therefore, in this embodiment, an insulating layer or an insulating sleeve is provided on the metal pipe to ensure the insulation between the metal pipe and the large-capacity battery 1 when in use.

[0072] Preferably, an insulating layer and an insulating sleeve are provided on the heat transfer tube 3 to form a double insulation structure; this double insulation arrangement enables the heat transfer tube 3 to maintain reliable insulation performance with the large-capacity battery 1 when heat is exchanged with the large-capacity battery 1, even if one of the insulating layer or the insulating sleeve is damaged, thereby improving the safety of the large-capacity battery 1 during use. The specific structure of the heat transfer tube 3 with an insulating layer and an insulating sleeve is described in detail below, taking the metal tube as an aluminum tube as an example.

[0073] When an insulating layer is provided on an aluminum tube, the insulating layer is formed on the tube wall of the aluminum tube and is an integral structure with the aluminum tube. The insulating layer can be implemented in the following ways:

[0074] First, a ceramic coating, i.e., a high-temperature electrical insulation coating, is formed on the wall of the aluminum tube to form an insulating layer. The ceramic coating may be boron nitride, aluminum oxide, or copper fluoride coating. However, the insulating layer formed in this way is easy to fall off and the processing cost is high.

[0075] Second, a layer of insulating material (such as insulating paint, etc.) is coated on the wall surface of the aluminum tube to form an insulating layer; this method is easy to process and implement, and the processing cost is low;

[0076] Third, the aluminum tube is oxidized to form an insulating layer. Oxidation is to use the chemical reaction between the metal surface and oxygen to form an oxide film to improve the insulation performance of the metal surface. For example, electrochemical oxidation method, etc. Specifically, the aluminum tube is oxidized to form a hard oxide layer. The insulating layer formed by this method is not easy to fall off, and the insulation performance is relatively good.

[0077] It should be noted that the tube wall can be the outer tube wall of the aluminum tube or the inner tube wall, preferably the outer tube wall. The thicker the hard oxide layer formed by oxidation treatment, the better the insulation, but its thermal conductivity will be reduced. In this embodiment, the thickness of the hard oxide layer is preferably 20um to 50um. The hard oxide layer of this thickness ensures the insulation performance while also making the side wall of the aluminum tube have better thermal conductivity.

[0078] The above-mentioned insulating sleeve can be specifically made of insulating materials with good thermal conductivity, so that it has excellent thermal conductivity and good insulation performance. In this embodiment, the insulating sleeve adopts a thermally conductive plastic sleeve or a thermally conductive rubber sleeve with good insulation and thermal conductivity, such as a thermally conductive silicone sleeve, etc. At the same time, the thickness of the insulating sleeve is preferably 0.1mm~1.5mm, which can ensure good thermal conductivity while ensuring excellent insulation performance. The cross-sectional shape of the insulating sleeve can be circular, U-shaped, or C-shaped, as long as it can be sleeved on the aluminum tube with an insulating layer to achieve insulation at the contact point between the aluminum tube and the polarity terminal 13 of the single battery 12. At the same time, the cross-sectional shape of the above-mentioned insulating sleeve is preferably the same as the cross-sectional shape of the aluminum tube, so that the insulating sleeve can be tightly nested on the aluminum tube to improve the thermal conductivity of the aluminum tube.

[0079] like Figure 2As shown, when the heat transfer tube 3 is installed, a through groove or through hole is provided at the position where the polarity terminal 13 of the single battery 12 extends out of the avoidance hole 113, as a clamping portion 131; compared with the through hole, the through groove is more convenient for on-site installation, and the installation requirements are relatively low. The through groove is arranged in a C-shaped cross section, and the opening width of the C-shaped through groove is smaller than the widest part of the through groove. Such a design is conducive to the interference fit of the heat transfer tube 3 in the through groove. The arc formed at both ends of the C-shaped through groove has natural tension, which is conducive to the heat transfer tube 3 being tightly clamped in the through groove.

[0080] In this embodiment, the polarity terminal 13 of the single battery 12 is a cylinder. In this case, the through groove can be set on the side wall or end face of the cylinder. The through groove or through hole is provided on the side wall. Compared with the through groove provided on the end face, the contact area between the heat transfer tube 3 in the through groove or through hole and the inner wall of the through groove or through hole is larger, and the heat exchange efficiency is higher. In addition, when the through groove or through hole is located on the side wall, the entire area of ​​the end face can be used as an electrical connection area. In addition, two through grooves or through holes can be provided on the side wall of the pole at the same time to increase the number of heat transfer tubes 3 placed and further improve the heat exchange efficiency. The above-mentioned heat transfer tube 3 is fixed in the through groove or through hole of the polarity terminal 13 of the large-capacity battery 1 to process the heat on the top of the large-capacity battery 1.

[0081] After the heat transfer tube 3 exchanges heat with the large-capacity battery 1, the heat transfer medium absorbs heat in the heat transfer tube 3 and is then transferred to an external heat treatment device through the liquid inlet manifold and the liquid return manifold for treatment. The heat treatment device is a device with heating and / or cooling functions, which is used to increase or decrease the temperature of the heat transfer medium (specifically, water, ethylene glycol / water, propylene glycol / water, methanol / water, ethanol / water, calcium formate / water, etc.). For example, the heat transfer unit is specifically a heater, a cold and warm machine, or a refrigerator with a compressor, a chiller, etc.

[0082] Example 3

[0083] During long-term use of the large-capacity battery 1, condensation will be generated on the surface due to the temperature difference between the inside and outside of the heat transfer tube 3. When the condensation accumulates to a certain amount, it will penetrate into the gap between the polarity terminal 13 of the single battery 12 and the avoidance hole 113, causing the polarity terminal 13 of the single battery 12 to be electrically conductive with the shell 11, which may cause the same single battery 12 to short-circuit.

[0084] like Figure 7 and Figure 8As shown, this embodiment overcomes the above problems by optimizing the top structure of the large-capacity battery 1 and laying an insulating sealant layer 14 on the top plate of the shell 11. The end face of the polarity terminal 13 of each single battery 12 extends out of the insulating sealant layer 14, which is used to connect with the first electrical connector 17 or the second electrical connector 18; the liquid inlet end and the liquid outlet end of the heat transfer tube 3 extend out of the insulating sealant layer 14, which is used to connect with the liquid inlet manifold and the liquid return manifold. The first electrical connector 17 is a connecting device for connecting each single battery 12 in parallel, and the second electrical connector 18 is a connecting device for connecting two large-capacity batteries 1 in series, and can also be a connecting device for connecting the large-capacity battery 1 with an external load.

[0085] like Figure 7 and Figure 8 As shown, in this embodiment, an insulating sealant layer 14 is laid on the top plate of the shell 11, and a part of the polarity terminal 13 of each single battery 12 is covered by the insulating sealant layer 14, and the end surface of the polarity terminal 13 of each single battery 12 extends out of the insulating sealant layer 14 and is connected to the first electrical connector 17 and / or the second electrical connector 18; the main parts of the heat transfer tube 3 are all covered by the insulating sealant layer 14, and the liquid inlet end and the liquid outlet end of the heat transfer tube 3 extend out of the insulating sealant layer 14, which is used to be connected to the liquid inlet manifold and the liquid return manifold.

[0086] In some other embodiments, the thickness of the insulating sealant layer 14 can be smaller, lower than the main body of the heat transfer tube 3, or cover a part of the main body of the heat transfer tube 3, as long as condensation cannot enter the gap between the polarity terminal 13 of the single battery 12 and the avoidance hole 113.

[0087] The insulating sealant used in this embodiment is generally a battery potting glue commonly used in batteries, such as a silicone thermal conductive potting glue, which has good sealing, insulation, vibration resistance, heat dissipation and waterproof functions. In order to prevent the insulating sealant from overflowing, during the injection process of this embodiment, a glue injection mold can be added around the edges of the top plate of the shell 11 to ensure that the insulating sealant can be smoothly injected. After the injection is completed, demoulding is performed.

[0088] like Figure 8 As shown, on the basis of the above structure, this embodiment further provides an insulating protective cover 15 on the top of the large-capacity battery 1, thereby providing insulating protection for the polarity terminal 13, avoiding the potential safety hazard of the polarity terminal 13 being exposed during the operation of the large-capacity battery 1, and also avoiding the problem of some foreign matter in the external environment falling into the position of the polarity terminal 13 and causing the large-capacity battery 1 to short-circuit, thereby improving the safety of the large-capacity battery 1.

[0089] It should be noted that if the insulating protective cover 15 completely covers the polarity terminal 13, it will make the electrical connection of such a large-capacity battery 1 difficult. Therefore, in this embodiment, a slit is provided on the side wall of the insulating protective cover 15, through which the second electrical connector 18 can be connected to the polarity terminal 13 of the single battery 12, thereby achieving electrical connection. It should also be noted that a channel for the liquid inlet and liquid outlet of the heat transfer tube 3 to extend out needs to be provided on the side wall of the insulating protective cover 15.

Claims

1. A large-capacity battery, comprising a housing and a plurality of single cells arranged in the housing in the same direction; a gas sharing chamber is provided in the housing, and the inner cavity of the gas sharing chamber is connected to the gas areas of all the single cells; It is characterized in that It also includes an air pressure balancing device. The shell has a through hole. The air pressure balancing device is arranged in the gas sharing chamber through the through hole to balance the air pressure in the gas sharing chamber with the air pressure of the external environment.

2. The large-capacity battery according to claim 1, characterized in that: The air pressure balancing device includes a balancing sleeve arranged in a gas sharing chamber and a balancing piston arranged in the balancing sleeve; the end of the balancing sleeve is connected to the through hole so that one end of the balancing sleeve is connected to the inner cavity of the gas sharing chamber, and the other end is connected to the external environment; the balancing piston can seal the inner cavity of the balancing sleeve, and the balancing piston can move in the balancing sleeve so that the air pressure in the gas sharing chamber tends to balance with the air pressure of the external environment.

3. The large-capacity battery according to claim 2, characterized in that: Limiting parts are arranged at both ends of the inner cavity of the balancing sleeve so that the balancing piston is always located in the inner cavity of the balancing sleeve.

4. The large-capacity battery according to claim 3, characterized in that: The balancing piston is a cylindrical sealing plug, and the outer wall of the balancing piston is provided with at least one circumferential annular sealing groove, and an annular sealing ring is arranged in the annular sealing groove.

5. The large-capacity battery according to claim 4, characterized in that: The end of the balancing sleeve connected to the through hole is provided with a positioning boss, the outer shell is provided with a positioning groove, and the positioning boss of the balancing sleeve is embedded in the positioning groove of the outer shell.

6. The large-capacity battery according to any one of claims 1 to 5, characterized in that: The top plate of the shell is provided with avoidance holes corresponding to the polarity terminals of each single cell; the polarity terminals of each single cell extend out of the avoidance holes, and the top plate area of ​​the shell corresponding to the avoidance holes is fixedly sealed with the shell of the single cell; an electrolyte sharing chamber is also provided in the shell, and the inner cavity of the electrolyte sharing chamber is connected with the electrolyte areas of all single cells.

7. The large-capacity battery according to claim 6, characterized in that: A clamping portion is provided at the position where each single cell polarity terminal extends out of the avoidance hole, a heat transfer tube is fixed on the clamping portion of each single cell polarity terminal, and the heat transfer tube is insulated from each single cell polarity terminal. The clamping portion is a through groove or through hole opened on each single cell polarity terminal.

8. The large-capacity battery according to claim 7, characterized in that: The heat transfer tube is a metal tube, and the metal tube has at least one of an insulating layer and an insulating sleeve.

9. The large-capacity battery according to claim 8, characterized in that: An insulating sealant layer is laid on the top plate of the shell, and the liquid inlet end and the liquid outlet end of the heat transfer tube extend out of the insulating sealant layer.

10. The large-capacity battery according to claim 9, characterized in that: An insulating protective cover is arranged on the top of the shell, and polarity terminals of each single battery are located inside the insulating protective cover.

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