Lithium-ion battery cell device

Abstract

The present invention relates to a prefabricated collector in a lithium-ion battery module, wherein the collector has a plurality of wells, each of which receives a lithium-ion battery cell and acts as both a gas barrier and a current conductor.

Description

Technical Field

[0001] The present invention relates to a battery module, and more particularly, to a battery module having a battery cell array for an electric vehicle. Background Art

[0002] Thermal runaway events are a known problem with lithium-ion battery modules during repeated charge / discharge cycles. The industry has been searching for solutions to minimize or prevent thermal runaway events, which can occur during rapid charging (e.g., supercharging), crashes, environmental exposure (overheating), or can occur spontaneously.

[0003] There is a constant need for new methods to minimize or prevent thermal runaway events in battery modules.

[0004] The disclosed embodiments may seek to achieve one or more of the desired results discussed in the present invention. Although embodiments of the present invention may avoid one or more of those desired results mentioned, it should be understood that some aspects of these embodiments may not necessarily avoid these results.

[0005] All cited patents, applications and documents are incorporated herein by reference in their entirety. In addition, where a definition or use of a term in a reference incorporated herein by reference is inconsistent or contrary to the definition of the term provided herein, the definition of the term provided herein applies and the definition of the term in the reference does not apply. Summary of the invention

[0006] In a general embodiment, the designed battery module includes a thermally conductive first substrate having a top surface, wells arrayed on at least one side of the first substrate, and a plurality of battery cells, each battery cell at least partially enclosed within each of the plurality of wells.

[0007] In another aspect that may be combined with the general embodiment, at least one of the wells has a sidewall in physical contact with a sidewall of each battery cell to transfer heat from the battery cell to the first substrate.

[0008] In another aspect that can be combined with the general embodiment, each battery cell has a side wall, and the entire length of the side wall of each battery cell can be enclosed in each well. Alternatively, in other embodiments, the battery cell is only partially or substantially enclosed in each corresponding well.

[0009] In another aspect that may be combined with the general embodiment, at least one of the battery cells is adhered to the inside of the well via an adhesive and is in indirect contact with a sidewall of the well to transfer heat from the battery cell to the first substrate.

[0010] In another aspect that may be combined with the general embodiment, there may be a cell interconnect disposed over or directly on the first substrate and electrically connected to the plurality of battery cells.

[0011] In another aspect that may be combined with the general embodiment, there may be a ventilation space disposed above the plurality of battery cells. In some embodiments, the ventilation space may be a closed ventilation space having a port.

[0012] In another aspect that may be combined with the general embodiment, there may be a first terminal electrically coupled to the first cell interconnect.

[0013] In another aspect that may be combined with the general embodiment, there may be a first terminal electrically coupled to the first substrate.

[0014] In another aspect that may be combined with the general embodiment, there may be a thermally conductive second substrate coupled to the first substrate, a layer of dielectric thermally conductive material disposed between the first substrate and the second substrate, and a second terminal electrically coupled to the second substrate.

[0015] In another aspect which may be combined with the general embodiment, the first substrate and the second substrate may be made of a conductive material, and the first terminal and the first cell interconnection may be electrically coupled to the first substrate.

[0016] In another aspect that may be combined with the general embodiment, the conductive material of the first substrate and the second substrate may be metal foam, and the dielectric thermally conductive material layer may be ceramic or high temperature polymer.

[0017] In another aspect that may be combined with the general embodiment, the metal foam may be a closed-cell or open-cell aluminum metal foam.

[0018] In another aspect that may be combined with the general embodiment, the first substrate may be an open-cell metal foam having interconnected cells, and a heat exchange medium may be present within the interconnected cells.

[0019] In another aspect that can be combined with the general embodiment, there can be a fluid inlet and a fluid outlet disposed on the first substrate, and the first substrate can have at least one fluid channel or at least one chamber disposed therein. The designed fluid channel can be fluidically connected to the interconnect unit.

[0020] In another aspect that may be combined with the general embodiment, the first substrate itself may act as a gas barrier such that a portion of each battery cell enclosed within each well is prevented from being exposed to gas from the vent space.

[0021] In another aspect that may be combined with the general embodiment, the gas barrier layer may be a ceramic layer or a high temperature polymer layer covering at least the top surface of the first substrate.

[0022] In another aspect that may be combined with the general embodiment, the gas barrier layer may be a layer that may be separated from the first substrate and may be disposed on top of or below the interconnect to isolate the sidewall of each battery cell from the ventilation space, thereby minimizing gas impact.

[0023] In another aspect that may be combined with the general embodiment, the substrate itself may serve as a collector for the battery cell array.

[0024] In another aspect that may be combined with the general embodiment, there may be a heat exchanger coupled to the first substrate, the second substrate, or both.

[0025] In another aspect that may be combined with the general embodiment, there may be more than two thermally conductive substrates coupled together to form a battery module; at least one thermal barrier may be provided at appropriate locations between some of the substrates to achieve some type of temperature isolation.

[0026] In another general embodiment, a method for protecting a battery cell contained in a battery module is designed, or a method for manufacturing a battery module having various desired characteristics is designed. The general embodiment includes prefabricating a collector from a thermally conductive material and prefabricating a plurality of wells in the collector. Each of the wells can receive a battery cell.

[0027] In another aspect that may be combined with the general embodiment, the novel method may include the step of providing a structure that isolates at least a majority of the side wall of each battery cell from the ventilation space to prevent gas impact on the inter-cell space.

[0028] In another aspect that may be combined with the general embodiment, the novel method may include the step of transferring heat from each battery cell to a heat exchange medium via the collector by providing sufficient contact between each battery cell and a wall of each well.

[0029] In another aspect that may be combined with the general embodiments, the novel method may include using a collector that is also conductive; the method may include using the collector as part of the current path during the charge / discharge cycle.

[0030] In another aspect that may be combined with the general embodiment, the novel method may include the step of structurally protecting the battery cells by encapsulating each battery cell with a shock absorbing material. In one embodiment, the shock absorbing material is a metal foam.

[0031] In another aspect that can be combined with the general embodiments, the novel method can include a prefabrication step of covering the metal foam with a thermally conductive dielectric material such as a ceramic or a high temperature polymer.

[0032] In another aspect that may be combined with the general embodiment, the novel method may include the step of coupling a heat exchanger to the collector / substrate.

[0033] In another aspect that may be combined with the general embodiment, the novel method may include the steps of enclosing a phase change fluid in interconnected cells of the metal foam and allowing at least a portion of the phase change fluid to evaporate from the interconnected cells during a thermal runaway event.

[0034] In another aspect that may be combined with the general embodiment, the novel method may include the step of coupling a fluid inlet and an outlet to the collector, thereby allowing a heat exchange medium to flow through the collector via conduits in the collector, chambers in the collector, interconnected units in the collector, or a combination of these options.

[0035] In another aspect that may be combined with the general embodiment, the novel method may include a prefabrication step of separating the collector with a layer of dielectric material, or a thermal barrier layer, or both.

[0036] In another aspect that can be combined with the general embodiment, the novel method can simplify the assembly of the battery module because a collector with an array of wells is provided to receive the battery cell array, thereby eliminating the need to fix the battery cell array in place and then carefully glue the battery cell array to the cold plate. In other words, the novel method can facilitate the picking and placing of battery cells in large quantities.

[0037] Accordingly, the present invention is directed to a battery module or a method of manufacturing a battery module that substantially obviates one or more problems due to limitations and disadvantages of the related art.

[0038] While this specification contains many specific implementation details, these should not be construed as limitations on the scope of what is claimed, but rather as descriptions of features specific to particular embodiments of particular inventions.

[0039] The details of one or more implementations of the subject matter described in this disclosure are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages of the subject matter will become apparent from the description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] It should be noted that the drawings may be in simplified form and may not be to exact scale. When referring to the disclosure herein, directional terms such as top, bottom, left, right, up, down, above, above, below, under, back, front, distal, and proximal are used with respect to the drawings for convenience and clarity only. These directional terms should not be construed as limiting the scope of the embodiments in any way.

[0041] Figure 1is a top front perspective view of an embodiment of a battery module according to one aspect of the present invention.

[0042] Figure 2 According to one aspect of the present invention Figure 1 Bottom front view of the battery module.

[0043] Figure 3 According to one aspect of the present invention Figure 1 Top rear perspective view of a battery module.

[0044] Figure 4 According to one aspect of the present invention Figure 1 A close-up view of the top view of the battery module.

[0045] Figure 5 According to one aspect of the present invention Figure 1 A close-up view of a top view of a battery module, where four wells are shown empty.

[0046] Figure 6 According to one aspect of the present invention, there is no heat exchanger Figure 1 Top front perspective view of a battery module.

[0047] Figure 7 According to one aspect of the present invention Figure 1 An exploded view of the battery module.

[0048] Figure 8 is a top front perspective view of another embodiment of a battery module according to an aspect of the present invention.

[0049] Fig. 9 According to one aspect of the present invention Figure 8 Bottom rear view of the battery module.

[0050] Fig.10 According to one aspect of the present invention Figure 8 Bottom plan view of a battery module.

[0051] Fig.11 According to one aspect of the present invention, Figure 8 Side view of the three substrates of a battery module with the heat exchanger removed.

[0052] Fig.12 According to one aspect of the present invention, Fig.10 Cross-sectional view taken along line CC in FIG.

[0053] Fig.13 According to one aspect of the present invention Figure 8 An exploded view of the battery module.

[0054] Fig.14 is a top front perspective view of yet another embodiment of a battery module according to an aspect of the present invention.

[0055] Fig.15A According to one aspect of the present invention Fig.13 Bottom rear view of the battery module.

[0056] Fig. 15B According to one aspect of the present invention Fig.13 A side plan view of a battery module.

[0057] Fig.16 According to one aspect of the present invention Fig.13 Bottom front perspective view of a battery module with the heat exchanger removed.

[0058] Fig.17 According to one aspect of the present invention Fig.13 An exploded view of the battery module.

[0059] Fig.18 The structure of a closed cell foam is shown.

[0060] Fig.19 The structure of an open-cell foam is shown.

[0061] Fig. 20 A structure of a metallic material with ceramic spheres embedded is shown.

[0062] Fig.21 is a close-up view of another embodiment of a battery module having a polymer plug according to an aspect of the present invention.

[0063] Fig. 22 is a perspective view of another embodiment of a battery module having a fluid inlet and a fluid outlet according to an aspect of the present invention.

[0064] Fig.23 According to one aspect of the present invention Fig. 22 A top view of the battery module.

[0065] Fig.24 is a perspective view of another embodiment of a battery module having a fluid inlet, a fluid outlet, an internal chamber, and an internal channel according to an aspect of the present invention.

[0066] Fig.25 is a side view of a designed battery module with ventilation space according to one aspect of the present invention.

[0067] The following list of references to elements in the drawings may be a useful guide when referring to elements in the drawings:

[0068] 100, battery module; 101, battery cell; 101A, front half battery cell array; 101B, rear half battery cell array; 102, ventilation space; 103, port; 110, substrate; 110A, substrate; 110B, substrate; 110C, substrate; 110D, substrate; 110E, substrate; 110F, substrate; 110G, substrate; 110H, substrate; 110J, substrate; 112, well; 1 13, sidewall of the well; 114, front surface; 115, rear surface; 116, top surface; 117, bottom surface; 118, side surface; 119, dielectric thermal conductive layer; 120, closed cell; 121, open cell; 122, ceramic sphere; 123, thermal insulation layer; 124, metal; 130, cell interconnect; 130A, cell interconnect; 130B, cell interconnect; 130C, cell interconnect; 130D, cell interconnect 130E, unit interconnection; 130F, unit interconnection; 130G, unit interconnection; 130H, unit interconnection; 130I, unit interconnection; 130J, unit interconnection; 130K, unit interconnection; 130L, unit interconnection; 130M, unit interconnection; 130N, unit interconnection; 130P, unit interconnection; 130Q, unit interconnection; 132, welding point; 134, first interconnection Connector; 136, second interconnector; 137, positive terminal of battery cell; 138, negative terminal of battery cell; 142, gas barrier layer; 150A, negative terminal of battery module; 150B, positive terminal of battery module; 160, heat exchanger; 161, polymer plug; 162, heat exchange medium; 164, fluid inlet; 166, fluid outlet; 167, channel; 168, chamber; 170, adhesive layer. DETAILED DESCRIPTION

[0069] Different aspects of the various embodiments may now be better understood by turning to the following detailed description of the embodiments, which are presented as illustrated examples as defined in the claims. It should be clearly understood that the embodiments defined by the claims may be broader than the illustrated embodiments described below.

[0070] The inventors have created a novel method to retain and protect each battery cell in a battery module by prefabricating a collector using a specific material with ideal properties and characteristics. The collector can have wells arranged in an array, each well encapsulating and retaining a lithium-ion battery cell. By partially or completely encapsulating the sidewalls of each battery cell, the impact of gas on the battery cell or on the inter-cell area can be prevented or minimized.

[0071] In one aspect, the collector can be made of a piece of thermally conductive material and can effectively transfer heat from the battery cell to the heat exchanger, thereby minimizing or preventing the occurrence of thermal runaway. In another aspect, the collector can effectively minimize or prevent thermal runaway in battery cells adjacent to a battery cell cluster that has already thermally runaway.

[0072] Throughout the present invention, this block of thermally conductive material is also referred to as a substrate or a subassembly of a substrate. The collector may comprise at least two such substrates. Alternatively, the collector may comprise a single substrate separated into different regions (with dielectric material).

[0073] As used herein, the term "substrate" 130 refers to a substance or skeleton to which the various components of a battery module (e.g., cell interconnects 130, battery cells 101) are coupled or attached. It can be a base or support for the battery cell 101. The substrate can be rigid or semi-rigid. The substrate can also be prefabricated before the other components of the battery module 100 (e.g., cell interconnects 130, battery cells 101) are attached to the substrate. The substrate may include a porous material. The substrate may be a block of the desired material, but not all embodiments require the substrate to be a solid block of material. It is also designed to use the same material to prefabricate a matrix or grid having a well or retaining frame that receives an array of battery cells. The matrix can effectively wrap each battery cell and can serve as a gas barrier, thermal conductor, and / or electrical conductor.

[0074] In some instances of the present invention, the term substrate 110 may be used interchangeably with the term collector. One of the designed functions of the collector is to act as a structural skeleton to safely support the other components of the battery module 100.

[0075] Alternatively, the collector may be made of a foam-like material with open or closed cells. The cells within the collector may hold a heat exchange medium, such as water or glycol, to achieve cooling in the battery module 100. In some embodiments, the heat exchange medium moves through the collector from an inlet to an outlet, which will be described in more detail later.

[0076] As briefly described above, the collector may be conductive and may be internally separated by a dielectric material so that the collector itself provides a specifically designed channel pattern / map for electrical current during the charge / discharge cycle.

[0077] The designed material for the collector may preferably have as low a resistivity as possible. The designed material for the collector may preferably have as high a thermal conductivity as possible. In some embodiments, the designed material for the collector may have a thermal conductivity higher than 30w / mk. In one embodiment, the designed material may have a thermal conductivity of about 40w / mk. In another embodiment, the designed material may have a thermal conductivity higher than 50w / mk. In another embodiment, the designed material may have a thermal conductivity higher than 120w / mk. In yet another embodiment, the designed material may have a thermal conductivity higher than 180w / mk. In another embodiment, the designed material may have a thermal conductivity higher than 220w / mk. The designed material for the collector may preferably have as low a density as possible. In some embodiments, the density of the material is 200 to 700kg / m 3 . In some embodiments, the density of the material should have a low impact on the module energy density. The designed material for the collector may preferably have as high a structural strength as possible. The designed material for the collector may have a melting temperature of about 600 degrees Celsius. Another designed material for the collector may have a melting temperature above 800 degrees Celsius. In another embodiment, the designed material may have a melting point above 900 degrees Celsius. In yet another embodiment, the designed material may have a melting point above 1000 degrees Celsius. A designed material for the collector may have a melting temperature between 600 degrees Celsius and 1000 degrees Celsius.

[0078] Furthermore, as will be described in greater detail later, the collector or substrate may be internally partitioned with insulating material so that the collector itself provides a specially designed thermal pathway.

[0079] The designed collector may additionally provide sufficient structural integrity to the battery module 100 to prevent or minimize fracture of the individual battery cells 101 in a vehicle collision.

[0080] It is important to recognize that while the disclosed generally rectangular collector configuration is particularly suitable for electric vehicles, other shapes and sizes may also be designed. In most embodiments, each well 112 is electrically insulated from each corresponding battery cell 101 by a layer of dielectric material. The dielectric material may be a sealant covering the substrate 110 (discussed in more detail later), an adhesive that bonds the battery cell 101 in the well 112, or both.

[0081] The designed collector / substrate 110 can be made of suitable materials to withstand the temperature extremes and chemical environments typical of lithium-ion battery modules; such materials include natural and synthetic polymers, various metals and metal alloys, naturally occurring materials, textile fibers, and all reasonable combinations thereof.

[0082] In one specific embodiment, the material is a metal foam. In yet another embodiment, the material can be an aluminum metal foam or a nickel metal foam. In another embodiment, the material is an aluminum open-cell metal foam having a pore radius equal to or less than 1 mm. In yet another embodiment, the material is an aluminum closed-cell metal foam having a pore radius of about 1 mm to 5 mm. Another embodiment includes an aluminum alloy embedded with ceramic or glass spheres, both of which will be described in more detail later. In another embodiment, the material can be a nanostructured foam made of carbon nanotubes. The designed melting temperature of suitable materials can exceed 1000 degrees Celsius, or exceed 800 degrees Celsius, or exceed 600 degrees Celsius, or a temperature above the thermal runaway temperature.

[0083] In most embodiments, the material used for substrate 110 may be structurally ductile to minimize breakage upon impact.

[0084] Figure 1 The architecture of one embodiment of a battery module 100 is generally depicted. The designed battery module 100 may have two thermally conductive substrates 110A, 110B, each having a top surface 116 (eg, Figure 4 Here, two substrates 110A, 110B are arranged side by side. As will be seen later in the context of the present invention, other arrangements of substrates 110 are also contemplated.

[0085] An array of wells 112 may be provided on the top sides of the two substrates 110A, 110B. Each well 112 may have a wall 113 (eg, Figure 5 The wells 112 are shaped like a cylindrical well 112 and are consistent with the size and shape of the corresponding battery cell 101 designed to be received in each well 112.

[0086] When the shape of the well 112 is consistent with the size and shape of the battery cell 101, the physical contact between the wall 113 of the well 112 and the side wall of the battery cell 101 can be maximized, thereby improving the heat transfer from the battery cell 101 to the substrate 110. In some embodiments, the battery cell 101 is placed in the well 112 without the use of a thermally conductive adhesive or any other thermally conductive substance. In other embodiments, before the battery cell 101 is dropped into its corresponding well 112, each well 112 is prepared with a droplet or spray of a suitable amount of thermally conductive adhesive.

[0087] The designed substrates 110A, 110B provide a simple placement process in battery production. As described above, a thermally conductive adhesive may or may not be necessary. In one embodiment, the thermally conductive adhesive may be a gas barrier to minimize gas impact on the battery cell 101. In other embodiments, no adhesive is used to ensure easy removal of the battery cell 101 at a later time.

[0088] The cross-sectional shape of the well 112 may not be circular. Furthermore, the cross-sectional shape of the well 112 need not be consistent with the size and shape of the battery cell 101. In such cases, an appropriate amount of thermally conductive adhesive placed in each well 112 will ensure sufficient contact between the wall 113 of each well 112 and the side wall of each battery cell 101, thereby improving heat transfer from each battery cell 101 to the substrate 110A, 110B.

[0089] The thermally conductive adhesive may be of a type that functions well in extreme temperatures and acidic environments.The adhesive may also be used to bond various other components to the substrates 110A, 110B, as will be described later.

[0090] A plurality of battery cells 101 are contained in a plurality of wells 112. Figure 1 As shown, each battery cell 101 is completely enclosed within each well 112. Although this particular embodiment contemplates each battery cell 101 being completely enclosed within each well 112, other embodiments are also contemplated in which the battery cells 101 are partially enclosed within the wells 112. In other words, the depth of the wells 112 may vary.

[0091] A shallower well 112 that exposes a portion of the sidewall 102 of the battery cell can still adequately protect the battery cell 101 from gas impingement and simultaneously effectively transfer heat.

[0092] In a particular embodiment, the percentage of exposed area of ​​the side wall of the battery cell is designed to be low enough to prevent or minimize thermal runaway events that can cause gas to impact the battery cell 101 through the exposed side wall of each battery cell. In this case, the exposure of the side wall of the battery cell is defined as a portion of the side wall of the battery cell that is not covered by the gas barrier material. In one embodiment, the percentage of exposed area of ​​the side wall of the battery cell is no more than 50% of the entire side wall. In another embodiment, the percentage of exposed area of ​​the side wall of the battery cell is no more than 30% of the entire side wall. In yet another embodiment, the percentage of exposed area of ​​the side wall of the battery cell is no more than 10% of the entire side wall. In another embodiment, the percentage of exposed area of ​​the side wall of the battery cell is no more than 5% of the entire side wall.

[0093] Disposed above the array of battery cells 101 is a layer of cell interconnects 130, details of which will be described later.

[0094] As is known in the art, there may be a vent space 102 disposed above the substrate 110 (eg, Fig.25 As shown). The designed ventilation space 102 may be an enclosed space. When a battery cell 101 enters a thermal event, gas may be released from the top side of that particular battery cell 101 into the ventilation space 102. There may be a port 103 leading to the outside of the battery module 100, allowing gas to escape from the ventilation space 102.

[0095] There may be a positive terminal 150B and a negative terminal 150A on the battery module 100. Figure 1 In FIG. 1 , the negative terminal 150A is disposed adjacent to the positive terminal 150B. Both the terminals 150A and 150B are disposed on the front surface 114 of the substrate 110. The terminals 150A and 150B are electrically coupled to the front surfaces 114 of the substrates 110A and 110B, respectively, which are conductive substrates.

[0096] The heat generated from the battery cells 101 can be transferred to the substrates 110A, 110B; the heat can then be transferred to the optional heat exchangers 160. These heat exchangers 160 can have different shapes and forms. Figure 1 , the heat exchanger 160 is a low thermal resistance cooling plate attached to the side surfaces 118 and the bottom surface 117 of the substrate subassembly including the substrates 110A, 110B.

[0097] Figure 2The bottom side of the battery module 100 with the cooling plate 160 attached thereto is shown. These cooling plates 160 can be attached to the substrates 110A, 110B via a thermally conductive adhesive or other known means. In most embodiments, no current should flow from the substrates 110A, 110B to the cooling plates 160. This can be achieved by providing a seal or covering layer of dielectric material on some or all surfaces of the substrates 110A, 110B. The designed sealing material includes ceramics, high temperature polymers, silicone potting glue, or any combination thereof. Alternatively or additionally, this can be achieved by using a dielectric thermally conductive adhesive between the substrates 110A, 110B and the cooling plates 160. The designed sealant or coating can have a dielectric strength of at least 4kv / mm. The designed sealant can be applied to the substrates 110A, 110B during the dipping process. In one design manufacturing process, multiple substrates 110A, 110B are sealed with dielectric materials, then bonded together with high temperature dielectric adhesives (to form subassemblies), and then the sealants are removed at certain locations to expose the underlying conductive material. The exposed conductive material can then be fused to other components, such as cell interconnects 130A, 1301 and terminals 150A, 150B.

[0098] In one embodiment of the design, the substrates 110A, 110B can be prefabricated by taking a piece of aluminum foam (with the well array) and sealing or covering the entire surface of the substrate 110 with a ceramic or other suitable dielectric sealant. In some embodiments, the covering layer / coating of ceramic can be about 0.5 mm from the surface of the metal foam. In another embodiment, the thickness of the coating can be between 0.2 mm and 0.7 mm. In yet another embodiment, the thickness of the coating can be between 0.5 mm and 1.0 mm. The designed sealant also includes a silicone-based sealant.

[0099] The sealant on the outside of the substrate 110 can withstand temperatures exceeding 1000 degrees Celsius. The sealant can act as a gas barrier to minimize or prevent gas impact on the battery cells 101 enclosed in the well 112.

[0100] The designed metal foam can have a density of about 300 to 600 kg / m3 before sealing with ceramic. While the embodiments discussed above provide that the metal foam can be sealed on its surface, another embodiment provides that the ceramic can be sealed further down into the internal cells of the metal foam; the designed density can be less than 1000 kg / m3. One way to control the penetration depth of the ceramic is to use a closed-cell metal foam with smaller pores.

[0101] In some embodiments, a sealing ceramic layer covering the substrates 110A and 110B separately ensures that current is not directly transferred from one substrate 110A to the adjacent substrate 110B when the substrate 110A is in contact with the adjacent substrate 110B. Alternatively or additionally, a separate dielectric material layer may be placed between the substrates 110A and 110B to ensure that current is not directly transferred from the former to the latter when the substrate 110A and the adjacent substrate 110B are in contact.

[0102] Essentially, a single collector having multiple substrates 110A, 110B may be electrically separated.

[0103] The need for galvanic isolation is to provide a specified current path / map.

[0104] The substrate subassembly may also be thermally separated. In some specially designed embodiments, a thermal barrier such as a ceramic wool sheet may be placed between the substrates 110 in the subassembly to form a thermal break. The thermal barrier may limit the spread of heat beyond a certain number of battery cells 101, or direct the spread of heat in a certain direction or route.

[0105] Figure 3 The back side of the battery module 110 is shown. Although in this embodiment, the terminals 150A, 150B are not provided on the back side, those skilled in the art will recognize that the terminals 150A, 150B may be placed elsewhere on the battery module to suit the needs.

[0106] Figure 4 A close-up view of the layers of the cell interconnect 130 is provided. Figures 1 to 7 In the illustrated embodiment, the layer of cell interconnects 130 actually includes nine separate interconnects 130A, 130B, 130C, 130D, 130E, 130F, 130G, 130H, 130I. Figure 4As can be seen in FIG. 1 , the nine interconnects 130A, 130B, 130C, 130D, 130E, 130F, 130G, 130H, 1301 do not physically contact each other. The cell interconnect 130A is a foil strip electrically connected to the substrate via a welding point 132, and has a second interconnect 136 portion electrically connected to the negative terminal of the first row of battery cells 101 by physically contacting the periphery of the top side of the first row of battery cells 101. The cell interconnect 130B is a foil strip having a first interconnect 134 portion electrically connected to the positive terminal 137 of the first row of battery cells 101. The cell interconnect 130B also has a second interconnect 136 portion electrically connected to the negative terminal of the second row of battery cells 101 by physically contacting the periphery of the top side of the second row of battery cells 101. Each of the cell interconnects 130C, 130D, 130E, 130F, 130G, 130H is designed to electrically connect one block of battery cells 101 to the next block of battery cells 101 similar to the interconnect 130B. The cell interconnect 1301 is similar to the interconnect 130A in that it electrically connects the last block of battery cells 101 to the substrate 110B via a weld. The concept of the cell interconnect 130 is known in the art and is disclosed in U.S. Pat. No. 10,347,894, the entire contents of which are hereby incorporated by reference herein.

[0107] exist Figure 5 In FIG. 1 , four battery cells 101 are missing from their respective wells 112. This is to illustrate the exposed side walls 113 of the wells 112. In this particular illustrated example, the side walls 113 of the wells 112 are as high as the battery cells 101.

[0108] In one designed embodiment, the material of the substrate 110 can act as a gas barrier. Thus, by enclosing the battery cell 101 inside the well 112, the substrate 110 acts as an effective gas barrier to prevent or minimize the sidewalls of the battery cell 101 from being exposed to the vent space 102.

[0109] Reference now Figure 6 , shows a prefabricated collector with two adjacent substrates 110A, 110B. An array of battery cells 101 has been placed into the prefabricated collector, and the cell interconnects 130A-I have not yet been mounted to the substrates 110A, 110B. The cooling plate 160 has not yet been attached to the side surfaces 118 of the substrates 110A, 110B. In one example of a prefabricated collector, the terminals 150A, 150B have already been installed.

[0110] Figure 7An exploded view of a battery module 100 is shown. In this embodiment, the two substrates 110A, 110B may be prefabricated from aluminum foam and individually sealed with ceramic or other thermally conductive and dielectric materials. The two substrates may then be bonded to each other with a thermally conductive adhesive to form a subassembly. The battery cells 101 are then placed into the wells 112, with or without adhesive drops in each well 120 to secure each respective battery cell 101 therein.

[0111] In this figure, an optional gas barrier layer 142 may be provided between the cell interconnect 130 and the array of battery cells 101. The engineered gas barrier layer 142 may be a high temperature flame retardant reinforcement that provides support for the interconnect 130. The engineered gas barrier layer 142 may also be an electrical insulator.

[0112] Furthermore, a thermally conductive but electrically insulating adhesive layer may be disposed between the heat exchanger 160 and the bottom side of the substrates 110D, 110E.

[0113] During battery charging, current enters the battery module 100 through the negative terminal 150A on the left. Although the substrate 110A on the left is sealed with a dielectric ceramic material on the outside, the negative terminal 150A on the left is directly connected to the metal portion of the substrate 110A through the dielectric ceramic cover layer. The current then travels to the substrate 110A on the left without reaching any of the battery cells 101. This is because the walls of the battery cells 101 are electrically insulated from the substrate 110A due to the dielectric ceramic seals in the well 112 and elsewhere on the substrate 110A. The current then travels to the cell interconnect 130A via a row of welds 132 electrically attached to the substrate 110A on the left.

[0114] Current then travels from cell interconnect 130A to the first row of battery cells 101 and cell interconnect 130B, as previously described in Figure 4 Because the current flows from the cell interconnect 1301 to the substrate 110B on the right side, and then flows out through the positive terminal 150B on the right side.

[0115] Figures 8 to 13 Another embodiment is provided in which the collector comprises three substrates 110C, 110D, 110E which are individually sealed and then adhered to each other. The collector has a larger substrate 110E (eg, Fig.11 It should be noted that only a single layer of battery cells 101 are enclosed in the collectors of the three substrates 110C, 110D, and 110E.

[0116] like Figure 8As shown, the designed battery module 100 has a large piece of cell interconnect 130J disposed and welded on the top side of the substrate 11C. Two smaller pieces of cell interconnects 130K, 130L are disposed and welded to the bottom sides of the substrates 110D, 110E, respectively (see Fig. 9 and Fig.13 ). Note that in this embodiment, each well 112 of the collector is a through channel with openings at both ends of each through channel. That is, the battery cell 101 disposed in the well 112 exposes its positive terminal 137 on one side of the collector and exposes its negative terminal 138 on the opposite side of the collector (see Fig.12 ).like Fig.12 and Fig.13 As shown, two groups of battery cells 101 are shown arranged in an alternating orientation.

[0117] All three substrates 110C, 110D, 110E are individually sealed with ceramic materials so that when the three substrates 110 are stacked together, current cannot flow from one substrate 110 to the next simply through their physical interfaces.

[0118] The front negative terminal 150A is electrically connected to a smaller substrate 110D in the front, and the rear positive terminal 150B is electrically connected to another smaller substrate 110E in the rear (see Fig.11 and Fig.12 ).

[0119] See now Fig.13 , the current first enters the battery module 100 via the negative terminal 150A on the front side of the battery module 100. The current then travels to the smaller substrate 110D, to which the negative terminal 150A is electrically attached. Because the substrate 110D is sealed with a ceramic material, the current is not directly passed to the unit cells 101 enclosed in the wells 112 of the substrate 110D. The current then passes to the bottom unit interconnect 130K welded to the substrate 110D. It should be noted here that Fig.13 and Fig.17 The cell interconnect 130 shown in FIG. 1 is different from Figure 4 The cell interconnects shown in . Fig.13 and Fig.17 The cell interconnect 130 in is in sheet form.

[0120] In one embodiment, using the designed collector as a structural backbone can achieve very thin interconnects 130. This can enable roll-to-roll processing by manufacturing the interconnects 130 on a roll of flexible metal foil. This can also reduce the cost of the cell interconnects 130.

[0121] The current travels from the cell interconnect 130K to the front half battery cell array 101A electrically connected to the small front cell interconnect 130K. The current travels from the front half battery cell array 101A to the large cell interconnect 130J.

[0122] Because the large piece of cell interconnect 130J is also electrically connected to the rear half of the battery cell array 101B (in the opposite orientation), current is now passed to that rear half of the battery cells 101B.

[0123] In addition to using a large sheet cell interconnect 130J to direct current between the two half arrays 101A, 101B of the battery cell 101, current is also transferred from the half array 101A to the half array 101B via the substrate 110C. This is because the sheet cell interconnect 130J is welded to the substrate 110C via welds 132. Using this configuration can help prevent overstress / overheating in the cell interconnect 130J.

[0124] The current then travels from the rear half array 101B of the battery cells 101 to the rear bottom smaller substrate 110E. The current then flows out of the battery module 100 via the rear positive terminal 150B, which is electrically attached to the rear bottom smaller substrate 110E.

[0125] Figures 14 to 17 Yet another embodiment is provided in which the collector comprises four substrates 110F, 110G, 110H, 110J adhered to each other. The collector has two lateral substrates 110G, 110H, which sandwich two smaller (front and back) adjacent substrates 110F, 110J (e.g. Fig.17 can be seen in ).

[0126] exist Fig.14 In the embodiment, the designed battery module 100 has a collector, a front cell interconnect 130M disposed on the front top side of the collector, and a rear cell interconnect 130N also disposed on the rear top side of the collector. A cooling plate 160 is attached to the side and bottom of the collector. The collector in this embodiment has wells 112, which are similar to Fig.12 , Fig.13 The through passage shown.

[0127] The negative terminal 150A is attached to the front smaller substrate 110F. Fig.15A In FIG. 1 , the bottom side of the battery module has a cooling plate 160; the rear end shows the positive terminal 150B attached to the smaller substrate 110J at the rear. Fig. 15B The relative positions of the two terminals 150A and 150B can be seen in FIG.

[0128] All four substrates 110 are individually sealed with a ceramic material so that when the four substrates 110 are assembled in physical contact with each other, current cannot flow from one substrate 110 to the next only through their physical interfaces.

[0129] See now Fig.17 , the current first enters the battery module 100 via the negative terminal 150A on the front center of the battery module 100. The current then travels to the smaller center substrate 110F to which the front negative terminal 150A is electrically coupled. Because the substrate 110F is sealed with a ceramic material, the current is not directly transmitted to any unit cell 101 in the system. The current is then transmitted to the front piece of the cell interconnect 130P via the welding point 132. The current travels from the cell interconnect 130P to the front half array 101A of the battery cells 101, and through these battery cells 101A to the top half of the cell interconnect 130M. Because the cell interconnect 130M is welded to the two lateral substrates 110G, 110H, the current then travels from the cell interconnect 130M to the two lateral substrates 110G, 110H. The current travels from the subsequent substrates 110G, 110H to the rear piece of the cell interconnect 130N welded to both substrates 110G and 110H.

[0130] It should be noted that the cell interconnects 130M, 130N are separate components and do not contact each other. They are also not directly electrically connected. Similarly, the cell interconnects 130P, 130P are separate components and do not contact each other. They are also not directly electrically connected.

[0131] The current then travels from the cell interconnect 130N to the rear half array 101B of battery cells 101 and then to the cell interconnect 130Q electrically connected to the opposite side of these battery cells 101. Because the cell interconnect 130Q is welded to the substrate 110J, the current then travels to the substrate 110J and then to the positive terminal 150B (not shown).

[0132] Additionally, a thermally conductive but electrically insulating adhesive layer 170 may be disposed between the heat exchanger 160 and the bottom side of the substrates 110F, 110G, 110H, 110J.

[0133] Most of the embodiments disclosed herein provide a collector that uses a metal foam subassembly to transfer heat and current during a charge / discharge cycle. For example, the metal foam that makes up the substrate 110 can be part of the current path. In a simplified example, the current is transferred from the negative terminal 150A → first metal foam → cell interconnect 130 → battery cell 101 → second metal foam → positive terminal 150B. In those particular embodiments, the metal foam is an essential part of the current path during the charge / discharge cycle.

[0134] It should be noted that in some embodiments, the substrate 110 may only transfer heat without transferring current during the charge / discharge cycle. For example, the collector may simply serve as a holder for the battery cell 101 to protect the battery cell 101 from external forces and impacts, rather than being part of the current path. In a simplified example, the current is transferred from the negative terminal 150A→cell interconnect 130→battery cell 101→positive terminal 150B. The material constituting the substrate 110 in these examples does not have to be conductive. In one embodiment, the substrate 110 is preferably a dielectric material.

[0135] As described above, the engineered material for substrate 110 may be thermally conductive, electrically conductive, ductile, shock absorbing, or any combination of these properties.

[0136] The shock absorbing properties of the designed substrate 110 can minimize or prevent the occurrence of side cracking of the battery cell. The industry has tried to solve this problem in the past by making batteries with thick walls. The designed substrate 110 can allow the use of thin-walled battery cells.

[0137] The designed metal foam can be Fig.18 The closed-cell foam shown, wherein a large number of cells 120 in the metal body 124 are closed so that they are not interconnected with each other. The designed metal foam can also be as Fig.19 An open cell foam is shown in which a large number of cells 124 in a metal body 124 are open such that they are interconnected with each other.

[0138] Another contemplated material includes a composite aluminum or metal alloy material in which a solid or hollow high temperature ceramic sphere or glass sphere 122 is embedded within a material 124 (e.g. Fig. 20 ). An example of a design for making such a material is to place aluminum or a metal alloy into a furnace crucible chamber with ceramic hollow spheres or high temperature hollow glass spheres to produce a molten metal with a dispersion of hollow spheres. This molten metal can then be poured onto a mold to form a substrate 110 with an array of wells 112.

[0139] In a particular embodiment where the metal foam has interconnected cells (e.g., open-cell foam), a heat exchange medium can be provided within the interconnected cells of the metal foam. In other words, a phase change medium such as water can be retained within the substrate 110. In one example, the amount of water per cell can be equal to about 10 kJ to 17 kJ of energy. When the battery cell 101 enters thermal runaway, the typical maximum PRM of water is about 20 kJ. In some embodiments, the water level does not need to reach full height because the thermal conductivity of the substrate 110 is able to keep the adjacent cells below the runaway temperature.

[0140] In one embodiment, the phase change fluid cannot be flammable.The phase change fluid is also designed to have a boiling temperature between 65 degrees Celsius and 150 degrees Celsius.

[0141] In one embodiment, a plurality of polymer plugs 161 may be provided on the top surface 116 of the substrate (see Fig.21 ). During a thermal event, one or more polymer plugs 161 may melt or burst due to elevated temperatures or pressures, thereby allowing water to evaporate through the openings left by the polymer plugs 161. The designed polymer plugs 161 may be made of a low temperature polymer that will melt between 85 degrees Celsius and 100 degrees Celsius and / or be designed to burst at a low threshold pressure. Although Fig.21 An array of polymer plugs 161 is shown in relation to an array of wells 112, but in one embodiment, the array of polymer plugs 161 is used to ventilate a single volume of fluid. Alternatively, fewer plugs 161 may also be designed.

[0142] Alternatively or optionally, there may be a vapor space within or above the substrate 110 where water vapor collects, and there may be a single pressure relief valve that allows the vapor to escape from the vapor space.

[0143] In yet another embodiment, evaporation at specific locations where polymer plugs 161 have melted during large thermal events can create a vacuum and draw more water into the hot spots. This design can work particularly well when there is an array of polymer plugs 161.

[0144] Reference now Figure 22 to Figure 24 , shows a simplified version of the battery module, where the terminals 150A, 150B are not shown. In these embodiments, there may be a fluid inlet 164 and a fluid outlet 166 that allow the heat exchange medium to pass through the interior space of the substrate 110. This can be achieved by using a metal foam with open pores (such as Fig.19 The heat exchange medium can be pushed through the substrate 110 to cool the substrate 110 and the battery cell 101. One way to effectively achieve this is to have an empty chamber 168, a connecting channel 167, or both, inside the substrate 110 to facilitate the heat exchange fluid to pass from the fluid inlet 164 to the fluid outlet 166. For example, there can be an empty chamber 168 near the inlet 164, and there can be an empty chamber 168 near the outlet 166 to better distribute the flow throughout the metal foam.

[0145] In other embodiments, the substrate 110 can be prepared by appropriately lining each well 112 and all exposed surfaces of the substrate 110 to ensure that no leakage of the heat exchange fluid occurs. For example, a 3003 aluminum alloy sleeve can be placed into each well 112 of the substrate 110 by pressure, and each surface 114, 115, 116, 117 of the substrate 110 is covered by a plate comprising 4004 series aluminum clad to the 3003 series aluminum. The 4004 can then be melted to seal the entire interior volume of the substrate 110.

[0146] In another embodiment, the heat exchanger 160 is then coated with a high voltage coating that can withstand a 4500 VDC breakdown and has a high insulation resistance (eg, >10 Gohm per cell interface). The coating may also be a high thermal conductivity coating.

[0147] Therefore, specific embodiments and applications of intra-cell devices for lithium-ion batteries have been disclosed. However, it is obvious to those skilled in the art that more modifications other than those already described are possible without departing from the concepts disclosed herein. Therefore, these disclosed embodiments are not limited except in the spirit of the appended claims. In addition, when interpreting the specification and claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms "include" and "comprise" should be interpreted as referring to elements, parts or steps in a non-exclusive manner, indicating that the mentioned elements, parts or steps can exist, use or combine with other elements, parts or steps that are not explicitly mentioned. As seen by those of ordinary skill in the art, non-substantial changes to the claimed subject matter (now known or later designed) are explicitly considered to be equivalent within the scope of the claims. Therefore, obvious replacements known to those of ordinary skill in the art now or later are defined as being within the scope of the defined elements. Therefore, the claims should be understood to include the content specifically shown and described above, the content that is conceptually equivalent, the content that can be obviously replaced, and the content that essentially contains the basic idea of ​​the embodiment. Furthermore, when the specification and claims refer to at least one of something selected from the group consisting of A, B, C... and N, the text should be interpreted as requiring at least one element from the group including N, rather than A plus N, or B plus N, etc.

Claims

1. A battery module, characterized in that: include: a prefabricated thermally conductive first substrate, the prefabricated thermally conductive first substrate having a top surface; a thermally conductive second substrate coupled to the first substrate; An array of wells, wherein the well array is arranged on at least one side of the first substrate and the second substrate; a plurality of battery cells, each battery cell of the plurality of battery cells being at least partially enclosed within each of the plurality of wells to spread heat away from the plurality of battery cells, each of the wells being electrically insulated from each corresponding battery cell by a layer of dielectric material; a first cell interconnect disposed over the first substrate and electrically connected to the plurality of battery cells; a ventilation space, the ventilation space being arranged above the plurality of battery cells; as well as a first terminal electrically coupled to the first cell interconnect; A layer of dielectric thermally conductive material is disposed between the first substrate and the second substrate, and a second terminal is electrically coupled to the second substrate.

2. The battery module according to claim 1, characterized in that: The first substrate and the second substrate include conductive materials, and the first terminal and the first cell interconnect are both electrically coupled to the first substrate.

3. The battery module according to claim 1, characterized in that: Each of the battery cells has a side wall, and the entire length of each side wall of the battery cell is enclosed within each of the wells.

4. The battery module according to claim 1, characterized in that: The ventilation space is a closed ventilation space with a port.

5. The battery module according to claim 2, characterized in that: The conductive material of the first substrate and the second substrate is metal foam, and the dielectric thermal conductive material layer is ceramic or high temperature polymer.

6. The battery module according to claim 5, characterized in that: The metal foam is closed-cell aluminum metal foam.

7. The battery module according to claim 5, characterized in that: The metal foam is open-cell aluminum metal foam.

8. The battery module according to claim 2, characterized in that: Also included is a heat exchanger coupled to at least one of the first substrate and the second substrate, wherein the conductive material of the first substrate and the second substrate has a plurality of ceramic spheres embedded therein.

9. The battery module according to claim 1, wherein: The first substrate is an open-cell metal foam having interconnected units, and further includes a heat exchange medium disposed in the interconnected units.

10. The battery module according to claim 9, characterized in that: It also includes a fluid inlet and a fluid outlet arranged on the first substrate, and at least one fluid channel or at least one chamber arranged in the first substrate and fluidically connected to the interconnection unit.

11. The battery module according to claim 1, wherein: The first substrate is a gas barrier so that a portion of each battery cell enclosed in each well is prevented from being exposed to gas impact from the ventilation space.

12. The battery module according to claim 1, wherein: A gas barrier layer is also included, wherein the gas barrier layer is a ceramic layer or a high temperature polymer layer covering at least the top surface of the first substrate.

13. The battery module according to claim 1, wherein: Also included is a gas barrier layer, wherein the gas barrier layer is separable from the first substrate and disposed on top of the interconnect to isolate a sidewall of each battery cell from the ventilation space.

14. A collector for a battery cell array in a battery module, characterized in that: The collector comprises: a first substrate comprising a sealed metal foam having a plurality of wells, each of the wells being capable of receiving a first battery cell; a second substrate comprising a sealed metal foam having a plurality of wells, each of the wells being capable of receiving a second battery cell; wherein the first substrate is coupled to the second substrate to allow heat conduction between the first substrate and the second substrate; The first substrate is electrically separated from the second substrate by a dielectric material layer, and each of the wells is electrically insulated from each corresponding battery cell by the dielectric material layer.

15. The collector according to claim 14, characterized in that The sealed metal foam is a closed-cell aluminum metal foam sealed with ceramic.

16. The collector according to claim 14, characterized in that Also included is a thermally conductive third substrate coupled to the second substrate, and a thermal barrier disposed between the second substrate and the third substrate.

17. A method for protecting a plurality of battery cells contained in a battery module, characterized in that: The method comprises: Prefabricating the collector from a thermally conductive material, including separating the collector with a layer of dielectric material, or a thermal barrier layer, or both; Prefabricate a plurality of wells in the collector, each of the wells being used to receive each of the plurality of battery cells; placing each battery cell of the plurality of battery cells into each well of the plurality of wells; isolating at least a majority of the sidewalls of each battery cell from the vent space to prevent gas impingement on the inter-cell space; and Heat is transferred from each battery cell to a heat exchange medium via the collector by providing sufficient contact between each battery cell and the walls of each well, each of the plurality of wells being electrically isolated from each corresponding battery cell by a layer of dielectric material.

18. The method according to claim 17, characterized in that The thermally conductive material of the collector is also electrically conductive and also includes using the collector as part of a current path during a charge / discharge cycle.

19. The method according to claim 17, characterized in that Also included is structurally protecting the plurality of battery cells by enclosing the battery cells with the thermally conductive material, wherein the thermally conductive material includes a shock absorbing material, and wherein the shock absorbing material is a metal foam.

20. The method of claim 18, wherein: The thermally conductive material of the collector is a metal foam, and the prefabrication step includes covering the metal foam with a thermally conductive dielectric material.

21. The method of claim 19, wherein: Also included is electrically coupling a first terminal and a first cell connector to the collector, and electrically coupling the first cell connector to a battery cell array, thereby allowing current to flow from the first terminal to the collector, then to the first cell connector, and then to the battery cell array.

22. The method of claim 17, wherein: Also included is coupling a heat exchanger to the collector.

23. The method of claim 17, wherein: The thermally conductive material is a metal foam having an interconnect unit, the method further comprising enclosing a phase change fluid in the interconnect unit and allowing at least a portion of the phase change fluid to evaporate from the interconnect unit during a thermal runaway event in at least one battery cell of the plurality of battery cells.

24. The method of claim 17, wherein: The thermally conductive material is a metal foam having interconnected cells, and the method further includes cooling the thermally conductive material by passing a heat exchange medium through the interconnected cells.

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