Heat spread blocking method for energy storage battery module capable of automatically adjusting battery spacing

Abstract

The invention discloses a heat spread blocking method of a battery spacing self-adjusting energy storage battery module, which comprises the following steps: assembling a battery module, the battery module comprises a liquid cooling plate and batteries arranged on the liquid cooling plate side by side, a spacing adjusting structure is arranged between adjacent batteries, and each battery is matched with a monitoring module; each battery is monitored in real time through the monitoring module, and the state of the battery is analyzed according to the monitored information; and according to the monitored state, the required distance between the adjacent batteries is calculated, and the corresponding distance adjusting structure is controlled to adjust the distance between the batteries. According to the heat propagation blocking method, self-adjustment of the distance between the batteries in the battery module can be realized in a heat accumulation stage before thermal runaway of the single batteries, or before abnormity of the single batteries, even thermal runaway of the single batteries but diffusion, blocking from abnormity to runaway of the single batteries is realized, the risk of thermal runaway of the battery module is reduced, and the service life of the battery module is prolonged. And the safety of the energy storage battery system is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of energy storage batteries, and in particular relates to a method for blocking heat spread of an energy storage battery module with self-regulating battery spacing. Background Art

[0002] Faced with the energy crisis and environmental pollution caused by the increasing scarcity of traditional primary fossil energy and its large-scale use, the development of new and renewable energy is the core and key to achieving global energy transformation and sustainable development. Lithium-ion batteries are the representative of current electrochemical energy storage technologies. With their flexibility and rapidity, they have become the fastest-growing energy storage technology in the field of electrical energy storage. However, electrochemical energy storage technologies represented by lithium-ion batteries have many safety hazards. Safety accidents frequently occur in large-scale energy storage power stations, and most of them are caused by thermal runaway of batteries. The safety issues of energy storage lithium-ion batteries have become a bottleneck technical problem that needs to be solved urgently in the large-scale promotion and application of energy storage technology.

[0003] However, electrochemical energy storage technology represented by lithium-ion batteries has many safety hazards. Safety accidents in large-scale energy storage power stations occur from time to time, and most of them are caused by thermal runaway of batteries. Lithium-ion battery safety accidents are the primary problem and fatal hidden danger in the development of large-scale energy storage technology. The safety issues of energy storage power stations have aroused widespread social concern, and various regions have to re-examine the implementation of large-scale energy storage projects. Compared with consumer energy storage products, the number of batteries used in energy storage power stations is huge and the storage energy is extremely high. Once a safety accident occurs, the loss is immeasurable, and the safety problem is more serious. Compared with consumer energy storage products, the number of batteries used in energy storage power stations is huge and the storage energy is extremely high. Once a safety accident occurs, the loss is immeasurable, and the safety problem is more serious. Safety accidents in energy storage power stations point to the design and operation problems of energy storage power stations on the one hand, and the intrinsic safety problems of lithium-ion batteries used for energy storage on the other. The safety problem of lithium-ion batteries for energy storage has become a bottleneck technical problem that needs to be solved urgently in the large-scale promotion and application of energy storage technology.

[0004] "Thermal runaway" refers to an overheating phenomenon in which a chain reaction of exothermic reactions occurs inside the battery, causing a sharp change in the battery temperature rise rate. The causes of thermal runaway mainly include three categories: mechanical abuse, electrical abuse, and thermal abuse. The thermal runaway of a single cell will cause heat spread (heat diffusion) in the battery module. Most batteries release a large amount of energy in a short time interval, which will cause huge safety hazards to the entire system. In addition, a large amount of flammable gas will also be generated during the battery thermal runaway process. When the gas concentration accumulates to a certain level, it will cause serious safety accidents such as fire and explosion.

[0005] Existing battery modules apply pre-tightening force to the batteries when they are grouped to ensure the structural rigidity of the batteries. However, this grouping method results in that if a single battery in the existing battery module experiences thermal runaway, the energy released by the battery failure will be transferred to adjacent batteries, which may cause serious safety accidents in severe cases. Summary of the invention

[0006] The purpose of the present invention is to provide a method for blocking the heat spread of a battery module with self-adjusting battery spacing. In the heat accumulation stage before the thermal runaway of a single cell, or when a single cell is abnormal, or even when a single cell is in thermal runaway, but before the spread, the spacing of the batteries in the battery module can be self-adjusted, so that the blockade from abnormal battery cells to runaway can be achieved, which greatly reduces the risk of thermal runaway of the battery module and improves the safety of the energy storage battery system.

[0007] In order to achieve the above purpose, the technical solution adopted by the present invention is:

[0008] A method for blocking heat spread of a battery module with self-adjusting battery spacing, comprising the following steps:

[0009] Step 1: Assemble a battery module, which includes a liquid cooling plate and batteries arranged side by side thereon, wherein the batteries are provided with tabs, and the outer sides of the two outermost batteries are provided with a clamping plate for applying a pre-tightening force, and a spacing adjustment structure is provided between adjacent batteries, and each battery is equipped with a monitoring module for monitoring temperature, voltage, current or internal resistance;

[0010] Step 2: Monitor each battery in real time through the monitoring module, and analyze the battery status based on the monitored information;

[0011] Step 3: Calculate the required spacing between adjacent batteries based on the monitored status, and control the corresponding spacing adjustment structure to adjust the spacing between the batteries.

[0012] Preferably, the spacing adjustment structure includes side plates fixedly connected to the front and rear sides of each battery, and an adjustment rod is provided between adjacent side plates.

[0013] Preferably, there is a gap between the single cells between the two clamp plates of the battery module assembled in step one, and the spacing adjusted by the adjusting rod is to adjust the gap between the single cells. When the battery module is assembled in step one, all the single cells are numbered as battery 1, battery 2...battery n, and the corresponding adjusting rods are numbered as rod 1, rod 2...rod m. When the xth battery is abnormal, all the adjusting rods 7 are operated to make the abnormal battery immobile and the other single cells move to both sides.

[0014] Preferably, the two clamp plates of the battery module assembled in step one can move in coordination with the structure for applying preload, the batteries at both ends are fixed on the two clamp plates, and there is no adjustment rod between the two middle batteries. When the battery module is assembled in step one, all single cells are numbered as left 1, left 2...left N and right 1, right 2...and right M, and the difference between N and M is 0 or 1; the corresponding adjustment rods 7 are numbered as left 1, left 1, left 2...left N-1 and right 1, right 2...and right M-1, and the adjustment rods on the front and rear sides are numbered the same. When an abnormality occurs in the battery, the clamp plate on the corresponding side moves outward, and then the spacing is adjusted by the adjustment rods corresponding to the two adjacent batteries.

[0015] Preferably, a guide rod is provided between the two fixture plates, and guide rod holes are provided on the side plates, and all the front side plates and all the rear side plates are penetrated by the front or rear guide rod.

[0016] Preferably, the side plate is also connected to a thin sheet that penetrates between adjacent single cells, and the thickness of the thin sheet is 0.2-0.5 mm.

[0017] Preferably, an adjustment and limiting structure is provided between adjacent single cells, the adjustment and limiting structure is a stretchable and shrinkable quadrilateral structure, and two diagonal portions of the quadrilateral structure are respectively mounted on two adjacent single cells.

[0018] The technical effect of the present invention is as follows: the present invention fully monitors the state quantity of the battery during operation, cleverly designs a feedback system for self-adjusting the battery spacing in the battery module according to the state quantity obtained by the gas, thereby realizing the blocking of the spread of thermal runaway of the energy storage battery module, and can ensure that the energy storage battery system always works in a normal working state during operation, reduce the battery performance decay rate, low cost, easy to implement, and high safety and reliability coefficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 This is a schematic diagram of the energy storage battery module after removing the side panels of Example 1.

[0021] Figure 2 This is a schematic diagram of the energy storage battery module of Example 1.

[0022] Figure 3 This is a top view of the energy storage battery module of Example 1.

[0023] Figure 4 This is a schematic diagram of the out-of-control battery in Example 1 after the spacing is adjusted.

[0024] Figure 5 Schematic diagram of a single cell and side panels.

[0025] Figure 6 This is a schematic diagram of the energy storage battery module of Example 2.

[0026] The text labels shown in the figure represent:

[0027] 1. Liquid cooling plate; 2. Fixture plate; 3. Guide rod; 4. Battery; 5. Tab; 6. Side plate; 7. Adjustment rod; 8. Guide rod hole; 9. Thin sheet; 10. Adjustment limit structure. DETAILED DESCRIPTION

[0028] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] Example 1

[0030] like Figure 1-5 As shown, the battery module of this embodiment includes a liquid cooling plate 1 and batteries 4 arranged side by side thereon, and pole ears 5 are arranged on the batteries 4. A clamp plate 2 for applying a preload is arranged on the outer sides of the two outermost batteries 4, and a spacing adjustment structure is arranged between adjacent batteries 4, and each battery 4 is equipped with a monitoring module for monitoring temperature, voltage, current or internal resistance; the spacing adjustment structure includes side plates 6 fixedly connected to the front and rear sides of each battery, and an adjustment rod 7 is arranged between adjacent side plates 6; the two clamp plates 2 can move in coordination with the structure for applying a preload, and the batteries 4 at both ends are fixed on the two clamp plates 2, and there is no adjustment rod between the two middle batteries 4.

[0031] Based on the above-mentioned battery spacing self-adjusting energy storage battery module, the present invention provides a method for blocking heat spread of the battery spacing self-adjusting energy storage battery module, comprising the following steps:

[0032] Step 1: number all the single cells 4 as left 1, left 2...left N and right 1, right 2...and right M, and the difference between N and M is 0 or 1; the corresponding adjustment rods 7 are numbered as left 1, left 1, left 2...left N-1 and right 1, right 2...and right M-1, and the numbers of the adjustment rods 7 on the front and rear sides are consistent.

[0033] Step 2: monitor each battery 4 in real time through the monitoring module, and analyze the battery status based on the monitored information;

[0034] Step three, according to the monitored status, if there is no abnormal state, no processing is required. If a single battery 4 is abnormal (thermal runaway battery), calculate the required spacing d between adjacent batteries, and then move the fixture plate 2 on the corresponding side. If the out-of-control battery is left 1 or right 1, the movement distance of the fixture plate 2 is d. At this time, the left 1 electric pull rod is correspondingly extended by d while the fixture plate 2 moves. If the out-of-control battery is other batteries, the corresponding movement distance of the fixture plate 2 is 2d. At this time, the corresponding two electric pull rods are correspondingly extended by d while the fixture plate moves. In this way, the distance between the batteries on both sides of the abnormal battery 4 and it is d, which plays a role in blocking the spread of heat, greatly reducing the risk of thermal runaway of the battery module and improving the safety of the energy storage battery system.

[0035] The above-mentioned embodiment 1 is optimized, specifically as follows: a guide rod 3 is provided between the two fixture plates 2, and a guide rod hole 8 is provided on the side plate 6, and all the front side plates and all the rear side plates are penetrated by the front or rear guide rod 3.

[0036] The above-mentioned optimized design can not only limit the position of all the side panels and guide them during movement, but also prevent the batteries from tipping over during the adjustment of the spacing, and also guide the movement of the fixture plate.

[0037] As a further optimization of Example 1, the side plate 6 is further connected with a thin sheet 9 which penetrates between adjacent single cells 4, and the thickness of the thin sheet is 0.2-0.5 mm. This sub-optimization avoids direct collision of the single cells during their movement, and can also apply thrust to the movement of the batteries.

[0038] Example 2

[0039] like Figure 6 As shown, compared with Example 1, this embodiment designs an adjustment limit structure 10 for limiting the maximum movement range (maximum spacing) of the single cell 4. The adjustment limit structure 10 is a stretchable and shrinkable quadrilateral structure, and the two diagonals of the quadrilateral structure are respectively installed on two adjacent single cells 4.

[0040] When the pull rod (generally an electric pull rod) is adjusted to separate two adjacent single batteries 4, the quadrilateral structure will become flattened until it approaches a straight line, thereby limiting the maximum spacing.

[0041] Example 3

[0042] The battery module of this embodiment includes a liquid cooling plate 1 and batteries 4 arranged side by side thereon, and pole ears 5 are arranged on the batteries 4. A clamp plate 2 for applying a preload force is arranged on the outer sides of the two outermost batteries 4, and a spacing adjustment structure is arranged between adjacent batteries 4, and each battery 4 is equipped with a monitoring module for monitoring temperature, voltage, current or internal resistance; the spacing adjustment structure includes side plates 6 fixedly connected to the front and rear sides of each battery, and an adjusting pull rod 7 is arranged between adjacent side plates 6; there is a gap between the single batteries 4 between the two clamp plates 2, and the spacing adjusted by the adjusting pull rod 7 is to adjust the gap between the single batteries 4.

[0043] Based on the above-mentioned battery spacing self-adjusting energy storage battery module, the present invention provides another method for blocking heat spread of the battery spacing self-adjusting energy storage battery module, comprising the following steps:

[0044] Step 1: When assembling the battery module in step 1, all the single batteries 4 are numbered as battery 1, battery 2...battery n, and the corresponding adjustment rods 7 are numbered as rod 1, rod 2...rod m.

[0045] Step 2: monitor each battery 4 in real time through the monitoring module, and analyze the battery status based on the monitored information;

[0046] Step three, according to the monitored status, if there is no abnormal state, no processing is required. For example, when the xth battery is abnormal, all the adjustment rods 7 are operated to make the abnormal battery immobile, and the other single cells 4 are moved to both sides. In this way, the batteries on both sides of the abnormal battery 4 can be separated by a corresponding distance, thereby playing a role in blocking the spread of heat, greatly reducing the risk of thermal runaway of the battery module and improving the safety of the energy storage battery system.

[0047] This embodiment has certain limitations when in use, mainly in that the spacing between the single cells between the fixture plates 2 is limited. If multiple cells are abnormal at the same time, it cannot be ensured that heat spread of all abnormal cells can be blocked.

[0048] It should be further explained that, in the description of the present invention, the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship 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 limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions.

[0049] Unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0050] Unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include the first feature being in direct contact with the second feature, or may include the first feature being in contact with the second feature through another feature between them instead of being in direct contact. Moreover, a first feature being "above", "above" and "above" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0051] The above-mentioned implementation modes are for explanation of the present invention rather than limitation of the present invention. It can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for blocking heat spread of a battery module with self-adjusting battery spacing, characterized in that: The steps include: Step 1: Assemble a battery module, which includes a liquid cooling plate and batteries arranged side by side thereon, wherein the batteries are provided with tabs, and the outer sides of the two outermost batteries are provided with a clamping plate for applying a pre-tightening force, and a spacing adjustment structure is provided between adjacent batteries, and each battery is equipped with a monitoring module for monitoring temperature, voltage, current or internal resistance; Step 2: Monitor each battery in real time through the monitoring module, and analyze the battery status based on the monitored information; Step 3: Calculate the required spacing between adjacent batteries based on the monitored status, and control the corresponding spacing adjustment structure to adjust the spacing between the batteries.

2. The method for blocking heat spread of a battery module with self-adjusting battery spacing according to claim 1, characterized in that: The spacing adjustment structure includes side plates fixedly connected to the front and rear sides of each battery, and an adjustment rod is provided between adjacent side plates.

3. The method for blocking heat spread of a battery module with self-adjusting battery spacing according to claim 2, characterized in that: The two fixture plates of the battery module assembled in step 1 can move in coordination with the structure for applying the pre-tightening force.

4. The method for blocking heat spread of a battery module with self-adjusting battery spacing according to claim 3, characterized in that: The batteries at both ends are fixed on two fixture plates, and there is no adjustment rod between the two batteries in the middle.

5. The method for blocking heat spread of a battery module with self-adjusting battery spacing according to claim 4, characterized in that: When assembling the battery module in step 1, all single cells are numbered as left 1, left 2...left N and right 1, right 2...and right M, and the difference between N and M is 0 or 1; the corresponding adjustment rods 7 are numbered as left 1, left 1, left 2...left N-1 and right 1, right 2...and right M-1, and the numbering of the adjustment rods on the front and rear sides is consistent. When an abnormality occurs in a battery, the fixture plate on the corresponding side moves outward, and then the spacing is adjusted by the adjustment rods corresponding to the two adjacent batteries.

6. The method for blocking heat spread of a battery module with self-adjusting battery spacing according to claim 2, characterized in that: A guide rod is matched between the two clamp plates, and a guide rod hole is opened on the side plate, and all the front side plates and all the rear side plates are penetrated by the front or rear guide rod.

7. The method for blocking heat spread of a battery module with self-adjusting battery spacing according to claim 6, characterized in that: The side plate is also connected with a thin sheet which penetrates between adjacent single cells, and the thickness of the thin sheet is 0.2-0.5 mm.

8. The method for blocking heat spread of a battery module with self-adjusting battery spacing according to claim 2, characterized in that: An adjustment and limiting structure is arranged between adjacent single cells. The adjustment and limiting structure is a stretchable and shrinkable quadrilateral structure, and two diagonal corners of the quadrilateral structure are respectively installed on two adjacent single cells.

9. The method for blocking heat spread of a battery module with self-adjusting battery spacing according to claim 2, characterized in that: There is a gap between the single cells between the two fixture plates of the battery module assembled in step 1, and the spacing adjusted by the adjusting rod is to adjust the gap between the single cells.

10. The method for blocking heat spread of a battery module with self-adjusting battery spacing according to claim 9, characterized in that: When the battery module is assembled in step 1, all the single cells are numbered as battery 1, battery 2...battery n, and the corresponding adjustment rods are numbered as rod 1, rod 2...rod m. When the xth battery is abnormal, all the adjustment rods 7 are operated to make the abnormal battery stand still and the other single cells move to both sides.

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