Prismatic battery can with thermally conductive insert

Abstract

A mechanical design of a rechargeable battery cell (e.g., a lithium ion battery) disposed within a prismatic can for use in electric vehicles and other electric devices. The improved design uses a thermally conductive insert to divide a battery cell into two adjacent volumes, each holding a pair of stacked layers of the battery cell. The thermally conductive insert conducts heat from the center of the battery cell to an active cooling channel disposed in a pair of cooling manifolds disposed on both vertical sides of the battery cell during battery recharging. Alternatively or additionally, an actively cooled bottom cold plate may be used. The pair of stacked battery layers may each be wound into a "gel roll" geometric configuration. The thermally conductive insert may be made of aluminum, an aluminum alloy, copper, or a copper alloy, and combinations thereof.

Description

Technical Field

[0001] The present disclosure relates generally to electrochemical devices. More specifically, aspects of the present disclosure relate to lithium-ion or lithium metal batteries with thermally conductive inserts for use in electric vehicles and other electric devices, such as electric aircraft. Background Art

[0002] The motor vehicles currently produced, such as modern cars, are initially equipped with a powertrain that operates to propel the vehicle and provide power for the vehicle's onboard electronics. For example, in automotive applications, the vehicle powertrain is typically represented by a prime mover that transmits drive torque to the vehicle's final drive system (e.g., differential, axle, corner module, wheels, etc.) through an automatic or manually shifted power transmission. Due to the availability and relatively cheap cost, light weight, and overall efficiency of reciprocating piston internal combustion engine (ICE) components, historically, automobiles have been powered by reciprocating piston internal combustion engine (ICE) components. As some non-limiting examples, such engines include compression ignition (CI) diesel engines, spark ignition (SI) gasoline engines, two-stroke, four-stroke, and six-stroke architectures, and rotary engines. On the other hand, hybrid electric vehicles and all-electric vehicles (collectively referred to as "electrically driven vehicles") utilize alternative power sources to propel the vehicle, and thus minimize or eliminate dependence on traction power from fossil fuel-based engines.

[0003] A full electric vehicle (FEV), commonly known as an "electric vehicle," is an electrically driven vehicle configuration that completely omits the internal combustion engine and the accompanying peripheral components of the powertrain system, instead relying on a rechargeable energy storage system (RESS) and a traction motor for vehicle propulsion. The engine components, fuel supply system, and exhaust system of an ICE-based vehicle are replaced by a single or multiple traction motors, rechargeable battery cells, and battery cooling and charging hardware in a battery-based FEV. In contrast, the powertrain of a hybrid electric vehicle (HEV) employs multiple traction power sources to propel the vehicle, most commonly operating an internal combustion engine component in conjunction with a battery-powered or fuel cell-powered traction motor. Because a hybrid electric-drive vehicle obtains its power from a source other than the engine, the HEV engine can be fully or partially shut down when the vehicle is propelled by the electric motor.

[0004] The high voltage (HV) electrical system controls the transmission of power between the traction motor and the rechargeable battery pack, which provides the necessary power for operating many hybrid electric and all-electric powertrains. In order to provide the power capacity and energy density required to propel the vehicle to the desired range at the desired speed, contemporary traction battery packs group multiple battery cells (e.g., 8-16+ battery cells / stack) into individual battery modules (e.g., 10-40+ modules / stack), which are electrically interconnected in series or parallel and mounted to the vehicle chassis, for example, by a battery pack housing or support bracket. Located on the battery side of the HV electrical system is a front-end DC-DC power converter, which is electrically connected to the traction battery pack to increase the voltage supply to the main DC bus and the DC-AC power inverter module (PIM). High-frequency bulk capacitors can be arranged between the positive and negative terminals of the main DC bus to provide electrical stability and store supplemental electrical energy. A dedicated electronic battery control module (EBCM) manages the operation of the battery pack and traction motors by operating in cooperation with the powertrain control module (PCM) and the power electronics package of each motor.

[0005] Battery arrays, such as battery modules, battery packs, etc., typically include multiple battery cells in relatively close proximity to each other. Batteries can be broadly classified as primary batteries and secondary batteries. Primary batteries, also known as disposable batteries, are intended to be used until exhausted, after which they are simply replaced with new batteries. Secondary batteries, more commonly known as rechargeable batteries, employ specific chemistries that allow such batteries to be repeatedly recharged and reused, thus providing economic, environmental, and convenience benefits over disposable batteries.

[0006] Rechargeable batteries can be used to power a variety of items such as toys, consumer electronics, motor vehicles, and aircraft. The specific chemistry of rechargeable batteries (such as lithium-ion battery cells) and external factors can cause internal chemical reactions that generate large amounts of heat energy. This abnormal chemical reaction may cause the battery cell to generate more heat than it can effectively dissipate. Exposure of the battery cell to elevated temperatures over an extended period of time may cause the battery cell to experience a thermal runaway event. Therefore, a thermal runaway propagation (TRP) event that begins in an individual battery cell may cause heat to spread to adjacent battery cells in the battery array, and cause a thermal runaway event to affect the entire battery pack and affect nearby temperature-sensitive components such as controllers, sensors, battery terminals, and connectors.

[0007] Individual battery cells of lithium-ion battery packs can generate a large amount of heat during charge and discharge cycles. The heat generated by such battery cells is mainly generated by exothermic chemical reactions and losses due to activation energy, chemical transport, and resistance to ion migration. Within a lithium-ion battery, as the battery cell temperature increases, a series of exothermic and gas-generating reactions can occur, which can push the battery assembly into an unstable state. If not suppressed, this thermal event can lead to a more accelerated heat generation state called "thermal runaway" (TR) or "thermal runaway propagation" (TRP), in which the battery system cannot return the internal battery components to normal operating temperatures. A battery module including multiple battery cells can be supported by an actively cooled bottom cold plate to control the temperature during battery charge and discharge operations. Summary of the invention

[0008] The present disclosure teaches an improved mechanical design for rechargeable battery cells (e.g., lithium-ion batteries) used in electric vehicles and other electric devices. The improved design uses a thermally conductive insert to divide the battery cell into one or more adjacent volumes that hold stacked layers of battery cells. The thermally conductive insert conducts heat from the center of the battery cell to an active cooling channel and / or an actively cooled bottom cold plate disposed in a pair of cooling manifolds during battery recharging, the pair of cooling manifolds being disposed on opposite vertical sides of the battery cell. The pair of stacked battery layers can each be wound into a "jellyroll" geometry. The thermally conductive insert can be made of aluminum, aluminum alloys, copper or copper alloys, and combinations thereof. The thickness of the thermally conductive insert is about 1 mm.

[0009] In some embodiments, a prismatic battery includes a prismatic battery can having a vertical Z direction oriented along a height of the prismatic battery can and a horizontal Y direction oriented along a width of the prismatic battery can. The battery can includes a thermally conductive insert disposed inside the prismatic battery can. The thermally conductive insert defines a first empty volume disposed within the prismatic battery can, the first empty volume being located on a first side of the thermally conductive insert. The thermally conductive insert also defines a second empty volume disposed within the prismatic battery can, which is located on a second side of the thermally conductive insert.

[0010] In some embodiments, the thermally conductive insert is disposed in a central location of the prismatic battery can.

[0011] In some embodiments, the thermally conductive insert is made of a thermally conductive metal selected from aluminum, aluminum alloys, copper or copper alloys, and combinations thereof.

[0012] In some embodiments, the prismatic battery further comprises: a first group of battery layers disposed within the first volume within the prismatic battery can; and a second group of battery layers disposed within a second volume within the prismatic battery can.

[0013] In some embodiments, the prismatic battery comprises a lithium-ion battery.

[0014] In some embodiments, the first set of battery layers and the second set of battery layers are wound in a "jelly roll" geometry.

[0015] In some embodiments, the thermally conductive insert has a thickness in a range from about 0.2 mm to about 1.2 mm.

[0016] In some embodiments, the thermally conductive insert has a thickness equal to about 0.8 mm.

[0017] In some embodiments, the prismatic battery can includes a pair of outer can walls oriented parallel to the plane of the thermally conductive insert.

[0018] In some embodiments, the thermally conductive insert is oriented parallel to a plane defined by a vertical Z-direction and a horizontal Y-direction.

[0019] In some embodiments, the thermally conductive insert is welded to the prismatic battery can.

[0020] In some embodiments, the thermally conductive insert is extruded simultaneously with extruding the prismatic battery can.

[0021] In some embodiments, the first group of battery layers and the second group of battery layers include a negative current collector layer. The anode electrode layer is disposed adjacent to the negative current collector layer. The separator layer is positioned adjacent to the anode electrode layer. The cathode electrode layer is positioned adjacent to the separator layer and opposite to the anode electrode layer. The positive current collector layer is positioned adjacent to the cathode electrode layer.

[0022] In some embodiments, the prismatic battery comprises a lithium ion battery. The negative current collector layer comprises copper. The anode electrode layer comprises a material selected from the following: graphite, lithium titanate, silicon / carbon, or tin / cobalt alloy, or a combination thereof. The separator layer comprises a microporous polyolefin polymer selected from the following: microporous polyethylene (PE), microporous polypropylene (PP) or microporous polyethylene terephthalate (PET) and a combination thereof. The cathode electrode layer comprises a compound selected from the following: lithium metal oxide, LiCoO2 (LCO), LiMn2O4 (LMO), LiFePO4 (LFP), nickel-manganese-cobalt oxide (NMC), or nickel-cobalt-aluminum oxide (NCA), and a combination thereof. The positive current collector layer comprises aluminum.

[0023] In some embodiments, the prismatic battery further comprises: a first electrode tab disposed on top of the first group of battery layers. A second electrode tab is located on top of the second group of battery layers. A current collector plate bridges and is electrically connected to the pair of first and second electrode tabs. An electrical terminal is located on top of the current collector plate. The current collector plate is welded to the first electrode tab. The current collector plate is welded to the second electrode tab. The electrical terminal is attached to and electrically connected to the current collector plate.

[0024] In some embodiments, a prismatic battery includes a prismatic battery can. A prismatic thermally conductive insert is located within the prismatic battery can. The insert defines a first volume disposed within the prismatic battery can, the first volume being located on a first side of the thermally conductive insert. The insert also defines a second volume disposed within the prismatic battery can, the second volume being located on a second side of the thermally conductive insert.

[0025] In some embodiments, the prismatic battery further comprises a first cooling manifold having a first plurality of cooling channels thermally coupled to a first vertical side of the prismatic battery can. The prismatic battery further comprises a second cooling manifold having a second plurality of cooling channels thermally coupled to an opposite second vertical side of the prismatic battery can.

[0026] In some embodiments, the prismatic battery further includes an actively cooled bottom cold plate disposed below the prismatic battery can.

[0027] In some embodiments, the prismatic battery further comprises a first electrode tab located on a first side of the prismatic battery can. A second electrode tab is located on a second side of the prismatic battery can; and the first side of the prismatic battery can is different from the second side of the prismatic battery can. No electrode tab is disposed on an upper surface of the prismatic battery can.

[0028] In some embodiments, an electric vehicle includes: a body having a passenger compartment, a plurality of wheels attached to the body, and a traction motor attached to the body and operable to drive one or more of the plurality of wheels to propel the electric vehicle. A traction battery pack is attached to the body and electrically connected to the traction motor. The traction battery pack includes a plurality of prismatic battery cells arranged in rows parallel to each other. The plurality of prismatic battery cells include a prismatic battery can and a thermally conductive insert located inside the prismatic battery can. The thermally conductive insert defines a first volume located within the prismatic battery can, the first volume being located on a first side of the thermally conductive insert. A second volume is located within the prismatic battery can, which is located on a second side of the thermally conductive insert. A first group of lithium-ion battery layers is located within the first volume of the prismatic battery can. A second group of lithium-ion battery layers is located within the second volume of the prismatic battery can.

[0029] In some embodiments, the thermally conductive insert is made of a thermally conductive metal selected from aluminum, aluminum alloys, copper or copper alloys, and combinations thereof.

[0030] In some embodiments, the prismatic battery can further includes a cooling manifold having a plurality of cooling channels, the cooling manifold being thermally coupled to a top surface of the prismatic battery can.

[0031] In some embodiments, the prismatic battery includes a sealed cooling enclosure having a coolant fluid inlet and a coolant fluid outlet that completely encloses the prismatic battery can. This provides immersion cooling of the prismatic battery.

[0032] The present invention also includes the following scheme:

[0033] Solution 1. A prismatic battery comprising:

[0034] a prismatic battery can having a vertical Z direction oriented along a height of the prismatic battery can and a horizontal Y direction oriented along a width of the prismatic battery can; and

[0035] A thermally conductive insert is disposed inside the prismatic battery can, the thermally conductive insert defining a first volume inside the prismatic battery can, wherein the first volume is disposed on a first side of the thermally conductive insert, and the thermally conductive insert defines a second volume inside the prismatic battery can, wherein the second volume is disposed on a second side of the thermally conductive insert.

[0036] Option 2. A prismatic battery according to Option 1, wherein the thermally conductive insert is made of a thermally conductive metal selected from aluminum, aluminum alloy, copper or copper alloy, or a combination thereof.

[0037] Solution 3. The prismatic battery according to Solution 1, further comprising:

[0038] a first group of battery layers disposed within the first volume within the prismatic battery can; and

[0039] A second group of battery layers is disposed within the second volume within the prismatic battery can.

[0040] Option 4. A prismatic battery according to Option 3, wherein the prismatic battery comprises a lithium-ion battery.

[0041] Option 5. The prismatic battery according to Option 3, wherein:

[0042] wherein the first set of battery layers is wound in a jelly roll geometry; and

[0043] Wherein the second set of battery layers is wound in a jelly roll geometry.

[0044] Option 6. The prismatic battery of Option 1, wherein the thermally conductive insert has a thickness in a range of about 0.2 mm to about 1.2 mm.

[0045] Option 7. A prismatic battery according to Option 1, wherein the prismatic battery can includes a pair of outer can walls oriented parallel to the plane of the thermally conductive insert.

[0046] Option 8. A prismatic battery according to Option 1, wherein the thermally conductive insert is welded to the prismatic battery can.

[0047] Option 9. A prismatic battery according to Option 1, wherein the thermally conductive insert is extruded simultaneously with extruding the prismatic battery can.

[0048] Option 10. The prismatic battery according to Option 3, wherein the first group of battery layers includes five layers, including:

[0049] a negative current collector layer;

[0050] an anode electrode layer disposed adjacent to the negative current collector layer;

[0051] a diaphragm layer disposed adjacent to the anode electrode layer;

[0052] a cathode electrode layer disposed adjacent to the separator layer and opposite to the anode layer; and

[0053] A positive current collector layer is disposed adjacent to the cathode electrode layer.

[0054] Option 11. The prismatic battery according to Option 3, further comprising:

[0055] a first electrode tab disposed on a top surface of the first group of battery layers;

[0056] a second electrode tab disposed on a top surface of the second group of battery layers;

[0057] a current collector plate bridging across and electrically connected to the first and second electrode tabs; and

[0058] an electrical terminal disposed on a top surface of the current collector plate;

[0059] wherein the current collector plate is welded to the first electrode tab;

[0060] wherein the current collector plate is welded to the second electrode tab; and

[0061] Wherein the electrical terminal is attached to and electrically connected to the current collector plate.

[0062] Solution 12. The prismatic battery according to Solution 10,

[0063] wherein the prismatic battery comprises a lithium-ion battery;

[0064] wherein the negative current collector layer comprises copper;

[0065] The anode electrode layer is selected from graphite, lithium titanate, silicon / carbon, tin / cobalt alloy, or a combination thereof;

[0066] wherein the separator layer is a microporous polyolefin polymer selected from the following: microporous polyethylene (PE), microporous polypropylene (PP) or microporous polyethylene terephthalate (PET) or a combination thereof;

[0067] wherein the cathode electrode layer is selected from: lithium metal oxide, LiCoO2 (LCO), LiMn2O4 (LMO), LiFePO4 (LFP), nickel-manganese-cobalt oxide (NMC) or nickel-cobalt-aluminum oxide (NCA), or a combination thereof; and

[0068] Wherein the positive current collector layer comprises aluminum.

[0069] Solution 13. A prismatic battery comprising:

[0070] Prismatic battery cans; and

[0071] a thermally conductive insert disposed within the prismatic battery can, the thermally conductive insert defining:

[0072] a first volume disposed within the prismatic battery can, the first volume being located on a first side of the thermally conductive insert, and

[0073] A second volume is disposed within the prismatic battery can, the second volume being located on a second side of the thermally conductive insert.

[0074] Embodiment 14. The prismatic battery according to embodiment 13, wherein the prismatic battery further comprises:

[0075] a first cooling manifold having a first plurality of cooling channels, the first cooling manifold being thermally coupled to a first vertical side of the prismatic battery can; and

[0076] A second cooling manifold having a second plurality of cooling channels is thermally coupled to an opposing second vertical side of the prismatic battery can.

[0077] Option 15. A prismatic battery according to Option 13, wherein the prismatic battery further includes an actively cooled bottom cold plate disposed below the prismatic battery can.

[0078] Embodiment 16. The prismatic battery according to embodiment 13 further comprises:

[0079] an upper surface of the prismatic battery can;

[0080] a first side of the prismatic battery can; and

[0081] a second side of the prismatic battery can;

[0082] a first electrode tab disposed on the first side of the prismatic battery can; and

[0083] a second electrode tab disposed on the second side of the prismatic battery can;

[0084] wherein the first side of the prismatic battery can is different from the second side of the prismatic battery can; and

[0085] No electrode tabs are provided on the upper surface of the prismatic battery can.

[0086] Solution 17. An electric vehicle, comprising:

[0087] a body having a passenger compartment;

[0088] a plurality of wheels attached to the vehicle body;

[0089] a traction motor attached to the body and operable to drive one or more of the plurality of wheels to propel the electric vehicle; and

[0090] a traction battery pack attached to the vehicle body and electrically connected to the traction motor;

[0091] wherein the traction battery pack comprises a plurality of prismatic battery cells arranged in mutually parallel rows;

[0092] Wherein, the plurality of prismatic battery cells include:

[0093] a prismatic battery can comprising a top surface;

[0094] a thermally conductive insert disposed within the prismatic battery can, the thermally conductive insert defining:

[0095] a first volume disposed within the prismatic battery can, the first volume disposed on a first side of the thermally conductive insert, and

[0096] a second volume disposed within the prismatic battery can, the second volume disposed on a second side of the thermally conductive insert;

[0097] a first group of lithium-ion battery layers disposed within the first volume in the prismatic battery can; and

[0098] A second group of lithium-ion battery layers is disposed within the second volume in the prismatic battery can.

[0099] Embodiment 18. The electric vehicle according to Embodiment 17, wherein the thermally conductive insert comprises a thermally conductive metal selected from aluminum, aluminum alloy, copper, or copper alloy, or a combination thereof.

[0100] Solution 19. The electric vehicle according to Solution 17, further comprising:

[0101] A top cooling manifold having a plurality of cooling channels, wherein the top cooling manifold is thermally coupled to the top surface of the prismatic battery can.

[0102] Solution 20. The electric vehicle according to Solution 17, further comprising:

[0103] a sealed cooling housing having a coolant fluid inlet and a coolant fluid outlet;

[0104] wherein the prismatic battery can is disposed entirely within the sealed cooling enclosure; and

[0105] Wherein, the prismatic battery can is cooled by immersion cooling.

[0106] The above summary of the invention does not represent every embodiment or every aspect of the present disclosure. On the contrary, the above summary of the invention only provides an overview of some novel concepts and features set forth herein. The above features and advantages of the present disclosure and other features and attendant advantages will be apparent from the following detailed description of the illustrated examples and representative modes for implementing the present disclosure when considered in conjunction with the accompanying drawings and the appended claims. In addition, the present disclosure expressly includes any and all combinations and sub-combinations of the elements and features presented above and below. BRIEF DESCRIPTION OF THE DRAWINGS

[0107] Figure 1 A schematic perspective view of an example of a prismatic battery cell according to the present disclosure is shown, wherein active cooling channels are provided on each end of the battery cell.

[0108] Figure 2 A schematic cross-sectional view (section AA) of an example of a jelly-roll prismatic battery cell of width A with active cooling channels disposed on each end of the battery cell according to the present disclosure is shown.

[0109] Figure 3 A schematic cross-sectional view (section AA) of an example of two half-sized jelly-roll prismatic battery cells of width A / 2 with active cooling channels on each end of the battery cell and with thermally conductive inserts according to the present disclosure is shown.

[0110] Figure 4 Graph showing an example of two-dimensional calculated temperature contours of a battery being recharged at time = 500 seconds for four different battery designs, each having a different thickness T of the thermally conductive insert in accordance with the present disclosure.

[0111] Figure 5 The invention is shown in accordance with the present disclosure Figure 4 Summary comparison graph of the calculated maximum (eg, peak) recharge temperature at the top of the battery cell at time = 500 seconds for the four different designs mentioned in .

[0112] Figure 6 A schematic perspective view of an example of an electric vehicle having a lithium-ion battery pack according to the present disclosure is shown.

[0113] Figure 7 A schematic perspective view of an example of a prismatic battery cell having cooling channels disposed in an actively cooled bottom cold plate disposed on a bottom end of the battery cell in accordance with the present disclosure is shown.

[0114] Fig. 8A A cross-sectional view (section BB) of an example of two half-sized jelly-roll prismatic battery cells having a width of B / 2 with side cooling and including a thermally conductive insert according to the present disclosure is shown.

[0115] Figure 8B A schematic front cross-sectional view (Section CC) of an example of a prismatic battery can having a thermally conductive insert and a pair of side cooling manifolds according to the present disclosure is shown.

[0116] Figure 8C A cross-sectional view (Section DD) of an example of two half-sized jelly-roll prismatic battery cells having a width of B / 2, supported by an actively cooled base plate, and including thermally conductive inserts in accordance with the present disclosure is shown.

[0117] Fig. 9 A cross-sectional view (section AA) of an example of an empty battery can with a thermally conductive insert welded to the battery can by a weld according to the present disclosure is shown.

[0118] Fig.10 A cross-sectional view (section AA) of an example of an empty battery can having an extruded thermally conductive insert according to the present disclosure is shown.

[0119] Fig.11 A cross-sectional view (Section DD) of an example of an empty battery can with an extruded thermally conductive insert according to the present disclosure is shown.

[0120] Fig.12 A cross-sectional cutaway view (section AA) of an example of a prismatic battery can having a thermally conductive insert according to the present disclosure is shown.

[0121] Fig.13 A schematic perspective cutaway view (section BB) of an example of a prismatic battery can according to the invention is shown, wherein a thermally conductive insert is arranged inside the prismatic battery can.

[0122] Fig.14 A cross-sectional cutaway view (Section BB) of an example of a prismatic battery can according to the present disclosure is shown, wherein a thermally conductive insert is disposed inside the prismatic battery can.

[0123] Fig.15 A schematic cross-sectional view of an example of five stacked layers of a lithium-ion battery according to the present disclosure is shown.

[0124] Fig.16 A schematic perspective view of an example of a prismatic battery can having positive and negative electrode tabs on the sidewalls of the prismatic battery can according to the present disclosure is shown.

[0125] Fig.17 A schematic elevation view of an example of a prismatic battery can with top cooling and thermally conductive inserts according to the present disclosure is shown.

[0126] Fig.18 A schematic elevation view of an example of a prismatic battery can with immersion cooling and a thermally conductive insert according to the present disclosure is shown. DETAILED DESCRIPTION

[0127] The present disclosure allows for many different forms of embodiments. Representative embodiments of the present disclosure are shown in the drawings and will be described in detail herein, with the understanding that these embodiments are provided as examples of the disclosed principles rather than limitations of the broad aspects of the present disclosure. In this regard, elements and limitations such as those described in the abstract, introduction, summary, and detailed description but not explicitly set forth in the claims should not be incorporated into the claims individually or collectively by implication, inference, or otherwise.

[0128] For purposes of this Detailed Description, unless specifically disclaimed: the singular includes the plural, and vice versa; the words "and" and "or" shall be both conjunctive and disjunctive; the words "any" and "all" shall mean "any and all"; and the words "include," "comprise," "contain," "have," and the like shall each mean "including but not limited to." In addition, approximate words, such as "approximately," "almost," "substantially," "substantially," "approximately," and the like, may each be used herein in a sense such as "at, close to, or nearly at," or "within 0-5% of," or "within acceptable manufacturing tolerances," or any logical combination thereof. Finally, directional adjectives and adverbs, such as front, rear, inboard, outboard, starboard (right side), port (left side), vertical, horizontal, upward, downward, front, rear, left, right, and the like, may be relative to the motor vehicle, such as the forward driving direction of the motor vehicle when the vehicle is operably oriented on a level driving surface. The drawings are not drawn to scale but are schematic diagrams showing geometric relationships between elements and objects.

[0129] The phrases "battery cell," "battery can," "battery housing," and "prismatic can" are used interchangeably. A "battery module" is defined as two or more individual battery cells grouped together as a single battery module. A "battery pack" is defined as two or more individual battery modules grouped together as a single battery pack. The phrases "battery module" or "battery pack" refer to a plurality of prismatic battery cans stacked side by side and arranged in a mutually parallel configuration inside a battery module / battery pack. The words "insert," "layer," and "sheet" are used interchangeably as they refer to a thermally conductive insert.

[0130] Figure 1 A schematic perspective view of an example of a prismatic battery cell 10 according to the present disclosure is shown, wherein a plurality of active cooling channels 14, 14' are disposed in cooling manifolds 12, 12' disposed on opposite sides of a battery can 21. The battery cell 10 is housed inside a prismatic (i.e., rectangular) battery can 21 and has a pair of electrode terminals 16 and 16' on a top plate 54 of the battery can 21. A pair of cooling manifolds 12 and 12' are disposed on both sides of the battery can 21, which have a plurality of cooling channels 14, 14', etc., which carry coolant fluids 18, 18', respectively, flowing in the "X" direction.

[0131] Figure 2A schematic cross-sectional view (section AA) of an example of a "jelly roll" prismatic battery cell 22 with width = A (in the "X" direction) according to the present disclosure is shown, wherein an active cooling manifold 12, 12' is provided on each end of the battery can 21, the active cooling manifold containing coolant fluid 18, 18' flowing in coolant channels 14, 14', respectively. The stacked (wound) battery layers 24 of the battery cell 22 are wound into a jelly roll geometry.

[0132] Figure 3 A schematic cross-sectional view (section AA) of an example of two half-sized jelly roll prismatic battery cells 26, 26' with width = A / 2 (in the "X" direction) according to the present disclosure is shown, wherein active cooling channels 12, 12' are disposed on the proximal and distal vertical sides of the battery cells 26, 26', respectively, and wherein a thermally conductive insert 30 is disposed inside the battery can 23. In some embodiments, the thermally conductive insert 30 is disposed in the middle of the battery can 23. The thermally conductive insert 30 is disposed inside the prismatic battery can 23. The prismatic battery can 23 defines a first volume 48 disposed on a first side of the thermally conductive insert 30 and a second volume 48' disposed on a second side of the thermally conductive insert 30. The thermally conductive insert 30 conducts heat outward from the center of the battery can 23 to the cooling channels 14, 14' in the cooling manifolds 12, 12'. The thermally conductive insert 30 may be made of a material having a high thermal conductivity suitable for the application, including, for example: aluminum, aluminum alloys, copper or copper alloys, and combinations thereof. In this embodiment, the YZ plane of the thermally conductive insert 30 is oriented parallel to the YZ plane of the battery can 23. The prismatic battery can 23 has a vertical Z direction oriented along the height of the prismatic battery can 23 and a horizontal Y direction oriented along the width of the prismatic battery can 23. The thermally conductive insert 30 has a wide plane oriented parallel to the plane defined by the vertical Z direction and the horizontal Y direction. The stacked battery layers 28 and 28' of the battery cells 26 and 26', respectively, are wound in a "jelly roll" geometric configuration.

[0133] Figure 4 Four examples of two-dimensional finite element calculated temperature contours of a lithium-ion battery cell 10 being recharged at time = 500 seconds for four different battery designs according to the present disclosure are shown, each having a different thickness T of the thermally conductive insert 30. The thicker the thermally conductive insert 30 (e.g., made of aluminum), the better the heat conduction to the cold plate (at the expense of lower battery energy density). The thickest thermally conductive insert 30 (e.g., T = 0.8 mm) has a maximum temperature of 50.1°C (50.1C) at T = 500 seconds, compared to a maximum temperature of 53.0°C (53.0C) for a thickness of T = 0 mm (i.e., no thermally conductive insert).

[0134] Figure 5 It is shown that according to the present disclosure Figure 4 1. A summary comparison graph of the calculated maximum (e.g., peak) recharge temperatures at the top of the battery cell 10 at time = 500 seconds for four different designs of aluminum thermally conductive inserts 30 referred to in . The x-axis is labeled as item 100; and the y-axis is labeled as item 102. As the thickness of the thermally conductive insert 30 increases from 0 mm to 0.8 mm, the maximum temperature decreases from 53.0° C. to 50.1° C. The thickness of the thermally conductive insert 30 can be in the range of 0.2 mm to 1.2 mm. However, the thicker the thermally conductive insert 30, the lower the energy density of the battery pack. Therefore, depending on which thickness is used for the thermally conductive insert 30, there is a tradeoff between the maximum battery temperature and the energy density of the battery cell 10.

[0135] Figure 6 A schematic perspective view of an example of an electric vehicle 1 having a battery pack 4 according to the present disclosure is shown. The electric vehicle 1 includes a vehicle body 2, a passenger compartment 5 disposed inside the vehicle body 2, a plurality of wheels 3, 3', etc. attached to the vehicle body 2, and a battery pack 4 located inside the electric vehicle 1. The electric vehicle 1 also includes one or more traction electric motors 13 attached to the vehicle body 2, which are operable to drive one or more of the wheels 3, 3', etc., thereby propelling the electric vehicle 1. The battery pack 4 is physically attached to the vehicle body 2 and electrically connected to the traction motor 13 by a cable 15.

[0136] Figure 7 A schematic perspective view of an example of a prismatic battery can 23 having cooling channels 14, 14' disposed in a bottom cold plate 60 supporting active cooling of a battery cell 10 according to the present disclosure is shown. The coolant 18 flows through the parallel cooling channels 14, 14', etc. in the X direction. The side walls 42 and 42' have been identified.

[0137] Fig. 8A A cross-sectional view (section BB) of an example of two half-sized jelly roll prismatic battery cells 32, 32' with width = B / 2 according to the present disclosure is shown, and the prismatic battery cells have side cooling and include a thermally conductive insert 30. Side cooling can be used in this embodiment (not shown in this view). The wide plane of the thermally conductive insert 30 is oriented parallel to the YZ plane. Electrode tabs 61 and 61' are provided on the top of each battery cell 32 and 32', respectively. A horizontal collector plate 64 spans the two electrode tabs 61 and 61', and the collector plate 64 is attached to the electrode tabs 61 and 61' by welds 62 and 62', respectively. An electrical terminal 66 for electrically connecting to the collector plate 64 is provided at the top of the battery can 23. Note that, Fig.13A close-up view of the top of the cell can 23 is shown. Due to the use of electrode tabs 61, 61', weld 62, and current collector plate 64, it is not possible to extend the thermally conductive insert 30 all the way to the top of the prismatic cell can 23. For this reason, the vertical extent of the thermally conductive insert 30 stops just a short distance at location 70 and does not extend all the way to the top surface 54 of the prismatic cell can 23.

[0138] Still reference Fig. 8A In some embodiments, the bottom end 71 of the thermally conductive insert 30 is optionally not connected to the lower wall 52 of the prismatic battery can 23. In this embodiment, it is sufficient for the thermally conductive insert 30 to be connected only to the side walls 42 and 42' of the prismatic battery can 23 (i.e., when side cooling is used, such as Figure 1 , 7 and 8B).

[0139] Figure 8B A schematic front cross-sectional view (section CC) of an example of a prismatic battery can 23 having a thermally conductive insert 30 and side cooling manifolds 12 and 12' and cooling channels 14 and 14, respectively, according to the present disclosure is shown. The thermally conductive insert 30 is attached (e.g., by welding or extrusion) to the side walls 42 and 42' of the prismatic battery can 30. However, in this embodiment, the upper extension 70 and the lower extension 71 of the thermally conductive insert 30 are not attached to the upper wall 54 and the lower wall 52, respectively, of the prismatic battery can 23 (i.e., because in this embodiment using side cooling, the upper wall 54 and the lower wall 52 are not actively cooled).

[0140] Figure 8C A cross-sectional view (section DD) of an example of two half-sized jelly-roll prismatic battery cells 32, 32' of total width = B according to the present disclosure is shown, wherein a thermally conductive insert 30 is disposed inside the battery can walls 36, 36', 42 and 42'. Cooling channels 14, 14', etc. are disposed in a thermally coupled, actively cooled bottom cold plate 60 that supports the battery can 23. The coolant 18 flows in the X direction inside the cooling channels 14, 14', etc. The plane of the thermally conductive insert 30 is oriented parallel to the YZ plane. Electrode tabs 61 and 61' are disposed on the top of each battery cell 32 and 32', respectively. A horizontal current collector plate 64 spans both the electrode tabs 61 and 61', and the current collector plate 64 is attached to the electrode tabs 61 and 61', respectively, by welds 62 and 62'. An electrical terminal 66 for electrical connection to the current collector plate 64 is disposed at the top of the battery can 23. Note that, Fig.13A close-up view of the top of the cell can 23 is shown. Due to the use of electrode tabs 61, 61', weld 62, and current collector plate 64, it is not possible to extend the thermally conductive insert 30 all the way to the top of the prismatic cell can 23. For this reason, the vertical extent of the thermally conductive insert 30 stops just a short distance at location 70, rather than extending all the way to the top surface 54 of the prismatic cell can 23.

[0141] Fig. 9 A cross-sectional view (section AA) of an example of an empty battery can 23 having a thermally conductive insert 30 of thickness = T according to the present disclosure is shown, which is welded to the proximal side 42 and the distal side 42' of the battery can 23 using two wire welds 40, 40', respectively. The empty volumes 48, 48' will be filled with a pair of half-sized battery cells (not shown).

[0142] Fig.10 A cross-sectional view (section AA) of an example of an empty battery can 23 having a proximal end wall 42 and a distal end wall 42', respectively, and a thermally conductive insert 30 having a thickness = T and a pair of side walls 20, 20', according to the present disclosure, the proximal end wall and the distal end wall and the thermally conductive insert are all co-extruded into a single unitary extrusion. The empty volume 48, 48' is defined by the side wall 20 or 20' and the end wall 42, 42' and the thermally conductive insert 30, and will eventually be filled with a pair of half-sized battery cells (not shown).

[0143] Fig.11 A cross-sectional view (section DD) of an example of an empty battery can 23 according to the present disclosure having a pair of side walls 20, 20' and a thermally conductive insert 30 of thickness = T, which is welded to the bottom end 52 of the battery can 23 by a weld 40. The empty volume 50, 50' is defined by the side walls 20 or 20' and end walls 42, 42' (not shown) and the thermally conductive insert 30, and will eventually be filled with a pair of half-sized battery cells (not shown). The thermally conductive insert 30 does not extend vertically all the way to the top of the prismatic battery can 23, but instead stops just short of the top at position 70. This configuration can be used with bottom cooling, such as Figure 7 as shown in .

[0144] Fig.12 A cross-sectional cutaway view (section AA) of an example of an empty battery can 23 with a thermally conductive insert 30 according to the present disclosure is shown. The thermally conductive insert 30 spans the entire width of the battery can 23 from the proximal side 42 to the distal side 42', and the plane of the thermally conductive insert 30 is parallel to the YZ plane. The empty volumes 48, 48' will eventually be filled with a pair of half-sized battery cells (not shown). However, it should be noted that in some embodiments, the wall thickness of the outer wall 20 or 20' can be the same or different from the wall thickness of the thermally conductive insert 30.

[0145] Fig.13 A schematic perspective cutaway view (section BB) of an example of a prismatic battery can 23 according to the present invention is shown, wherein a thermally conductive insert 30 is disposed inside the prismatic battery can 23. The thermally conductive insert 30 defines a pair of empty volumes 48 and 48' within the prismatic battery can 30 on either side of the insert 30. The thermally conductive insert 30 does not extend vertically all the way to the top surface 54 of the prismatic battery can 23, but stops at location 70 (to make room for internal electrical connections to the external electrical terminals 16').

[0146] Fig.14 A cross-sectional view (section BB) of an example of a prismatic battery can 23 with a thermally conductive insert 30 according to the present disclosure is shown. The thermally conductive insert 30 vertically spans almost the entire height H of the battery can 23 from the bottom plate 52 to near the top plate (i.e., the cover plate) 54. The wide plane of the thermally conductive insert 30 is parallel to the YZ plane. Electrode tabs 61 and 61' are respectively provided on the top of each battery cell 32 and 32'. A horizontal collector plate 64 spans the two electrode tabs 61 and 61', and the collector plate 64 is attached to the electrode tabs 61 and 61' respectively by welding portions 62 and 62'. Disposed at the top of the battery can 23 is an electrical terminal 66 for electrical connection to the collector plate 64. The thermally conductive insert 30 does not extend vertically all the way to the top surface 54 of the prismatic battery can 23, but stops at position 70 (to make room for internal electrical connection to the external electrical terminal 16').

[0147] Fig.15 A schematic cross-sectional view of an example of five layers of a lithium-ion battery cell 19 according to the present disclosure is shown. The five battery layers of the lithium-ion battery cell 19 include: a negative current collector layer 11, an anode electrode layer 6 disposed adjacent to the negative current collector layer 11, a separator layer 7 disposed adjacent to the anode electrode layer 6, a cathode electrode layer 8 disposed adjacent to the separator layer 7 and opposite to the anode electrode layer 6, and a positive current collector layer 9 disposed adjacent to the cathode electrode layer 8. The negative current collector layer 11 may include a copper sheet. The anode electrode layer 6 may include a material selected from the following: graphite, lithium titanate, silicon / carbon, or tin / cobalt alloy, and combinations thereof. The separator layer 7 may include a microporous polyolefin polymer selected from the following: microporous polyethylene (PE), microporous polypropylene (PP) or microporous polyethylene terephthalate (PET) and combinations thereof. The cathode electrode layer 8 may include a compound selected from the group consisting of lithium metal oxide, LiCoO2 (LCO), LiMn2O4 (LMO), LiFePO4 (LFP), nickel-manganese-cobalt oxide (NMC), or nickel-cobalt-aluminum oxide (NCA) and combinations thereof. Finally, in some embodiments, the positive current collector layer 9 may include aluminum.

[0148] Fig.16A schematic perspective view of an example of a prismatic battery can 23 according to the present disclosure is shown having anode and cathode electrode tabs 90 and 92 disposed on side walls 20 and 42, respectively, of the battery can 23. In this embodiment, no electrode tabs are disposed on the upper surface 54 of the battery can 23.

[0149] In some embodiments, more than one (ie, a plurality) of thermally conductive inserts 30 may be used inside each prismatic battery can 23 .

[0150] Fig.17 A schematic front view of an example of a prismatic battery can 23 with top cooling and a thermally conductive insert 30 according to the present disclosure is shown. In some embodiments, active cooling is applied to the top surface 54 of the prismatic battery can 23. The top cooling scheme includes a top coolant manifold 100, wherein a plurality of cooling channels 102, 102', etc. are disposed inside the top coolant manifold 100. In this embodiment, the thermally conductive insert 30 is attached (e.g., welded) only to the top surface 54 of the prismatic battery can 30, and not to the side walls 42, 42' or the bottom surface 52. Optionally, the thermally conductive insert 30 may be attached to some of all the walls of the prismatic battery can 23.

[0151] In some embodiments, various active cooling schemes (e.g., side cooling on both sides, bottom cooling, and top cooling) may be combined in various different ways to cool the prismatic battery, including but not limited to:

[0152] 1. Only side cooling;

[0153] 2. Cooling only the bottom;

[0154] 3. Cooling only on the top;

[0155] 4. Side and bottom cooling;

[0156] 5. Side and top cooling;

[0157] 6. Bottom and top cooling; and

[0158] 7. Side, bottom and top cooling.

[0159] Fig.18A schematic front view of an example of a prismatic battery can 23 cooled by immersion cooling with a thermally conductive insert 30 according to the present disclosure is shown. Immersion cooling is provided by enclosing the prismatic battery can within a sealed coolant shell 110, which carries a coolant fluid 116 (which can be a dielectric cooling fluid such as a hydrofluoroether, hydrocarbon, ester, silicone oil, water / ethylene glycol mixture, hydrofluoroether or fluorocarbon-based fluid, and combinations thereof) that completely surrounds the prismatic battery can 23 and the electrode terminals 16 and 16' on all sides with a flowing bath of coolant 116. The coolant fluid inlet 112 and the coolant fluid outlet 114 supply and remove the flowing coolant 116 from the sealed coolant shell 110, respectively. For immersion cooling, the thermally conductive insert 30 can be connected to at least one surface of the prismatic battery can 23, and the more surfaces the better.

[0160] Still reference Fig.18 In some embodiments, the coolant 115 does not circulate around the prismatic battery cans 23. Instead, the prismatic battery cans 23 are located in a stationary, non-circulating bath of coolant 116. In this case, there will be only one fill opening (not shown) at the top housing 110 for filling the housing 110 with the coolant fluid 116.

Claims

1. A prismatic battery comprising: a prismatic battery can having a vertical Z direction oriented along a height of the prismatic battery can and a horizontal Y direction oriented along a width of the prismatic battery can; as well as A thermally conductive insert is disposed inside the prismatic battery can, the thermally conductive insert defining a first volume inside the prismatic battery can, wherein the first volume is disposed on a first side of the thermally conductive insert, and the thermally conductive insert defines a second volume inside the prismatic battery can, wherein the second volume is disposed on a second side of the thermally conductive insert.

2. The prismatic battery according to claim 1, wherein: The thermally conductive insert is made of a thermally conductive metal selected from aluminum, aluminum alloy, copper or copper alloy, or a combination thereof.

3. The prismatic battery of claim 1 , further comprising: a first group of battery layers disposed within the first volume within the prismatic battery can; as well as A second group of battery layers is disposed within the second volume within the prismatic battery can.

4. The prismatic battery according to claim 3, wherein: The prismatic battery comprises a lithium-ion battery.

5. The prismatic battery according to claim 3, wherein: wherein the first set of battery layers is wound in a jelly roll geometry; and Wherein the second set of battery layers is wound in a jelly roll geometry.

6. The prismatic battery according to claim 1, wherein: The thermally conductive insert has a thickness in a range of about 0.2 mm to about 1.2 mm.

7. The prismatic battery according to claim 1, wherein: The prismatic battery can includes a pair of outer can walls oriented parallel to a plane of the thermally conductive insert.

8. The prismatic battery according to claim 1, wherein: The thermally conductive insert is welded to the prismatic battery can.

9. The prismatic battery according to claim 1, wherein: The thermally conductive insert is extruded simultaneously with the extrusion of the prismatic battery can.

10. The prismatic battery according to claim 3, wherein: The first set of battery layers includes five layers, including: a negative current collector layer; an anode electrode layer disposed adjacent to the negative current collector layer; a diaphragm layer disposed adjacent to the anode electrode layer; a cathode electrode layer disposed adjacent to the separator layer and opposite to the anode layer; and A positive current collector layer is disposed adjacent to the cathode electrode layer.

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