Prismatic battery box with a thermally conductive insert

Abstract

Prismatic battery (10), comprising: a prismatic battery box (23) with a vertical Z-direction aligned along a height of the prismatic battery box (23) and a horizontal Y-direction aligned along a width of the prismatic battery box (23); and a thermally conductive insert (30) arranged inside the prismatic battery box (23) and defining a first volume (48) inside the prismatic battery box (23), wherein the first volume (48) is arranged on a first side of the thermally conductive insert (30), and which defines a second volume (48') inside the prismatic battery box (23), wherein the second volume (48') is arranged on a second side of the thermally conductive insert (30); characterized in that the prismatic battery (10) further comprises: a first and a second cooling distributor (12, 12') and / or a lower cooling plate (60) and / or a top cooling distributor (100) and / or a cooling housing (110); wherein the first cooling distributor (12) is thermally connected to a first plurality of cooling channels (14) with a first vertical side of the prismatic battery box (23) and the second cooling distributor (12') is thermally connected to a second plurality of cooling channels (14') with an opposite, second vertical side of the prismatic battery box (23); wherein the actively cooled lower cooling plate (60) with a plurality of cooling channels (14, 14') is arranged below the prismatic battery box (23); wherein the top-side coolant distributor (100) is thermally coupled to a plurality of cooling channels (102, 102') with the top (54) of the prismatic battery box (23); and wherein the sealed coolant housing (110) carries a coolant (116) which completely surrounds the prismatic battery box (23) and electrode terminals (16, 16') on all sides with a flowing bath of coolant (116), wherein the coolant (116) is selected from the group consisting of hydrofluoroethers, hydrocarbons, esters, silicone oils, water / glycol mixtures, hydrofluoroether-based liquids, fluorocarbon-based liquids and combinations thereof.

Description

[0001] The invention relates to a prismatic battery according to the preamble of claim 1. The present description relates generally to electrochemical devices. In particular, aspects of this description relate to lithium-ion or lithium-metal batteries with a thermally conductive insert for use in electric vehicles and other electrically powered devices, such as electrically powered aircraft.

[0002] Today's production vehicles, such as modern automobiles, are originally equipped with a powertrain that propels the vehicle and supplies its onboard electronics. In motor vehicles, for example, the powertrain typically consists of a drive motor that transmits the drive torque to the vehicle's drive system (e.g., differential, axles, camshafts, wheels, etc.) via an automatic or manual transmission. Historically, motor vehicles were powered by internal combustion engines (ICEs) because these were readily available, relatively inexpensive, lightweight, and highly efficient. These engines include compression-ignition (CI) diesel engines, spark-ignition (SI) gasoline engines, two-, four-, and six-stroke engines, and rotary engines, to name just a few.Hybrid electric and fully electric vehicles (collectively referred to as "electrically powered vehicles"), on the other hand, use alternative energy sources to power the vehicle, thus minimizing or eliminating the dependence on a fossil fuel-based engine for traction power.

[0003] A full-electric vehicle (FEV) – colloquially referred to as an "electric car" – is a vehicle configuration with an electric drive system in which the internal combustion engine and its associated peripheral components of the drive system are completely eliminated, and instead a rechargeable energy storage system (RESS) and a traction motor are used to propel the vehicle. The engine assembly, fuel supply, and exhaust system of a combustion engine vehicle are replaced in a battery-powered FEV by one or more traction motors, rechargeable battery cells, and cooling and charging equipment.

[0004] Hybrid-electric vehicle powertrains (HEV powertrains), on the other hand, use multiple traction sources to propel the vehicle, usually an internal combustion engine in conjunction with a battery- or fuel cell-powered traction motor. Since hybrid and electric vehicles draw their energy from sources other than the engine, HEV engines can be switched off completely or partially while the vehicle is driven by the electric motor(s).

[0005] High-voltage electrical systems regulate the transfer of power between the traction motors and the rechargeable battery packs that supply the energy required to operate many hybrid-electric and all-electric powertrains. To provide the power capacity and energy density needed to propel a vehicle at the desired speed and over the desired range, modern traction battery packs combine multiple battery cells (e.g., 8-16+ cells / stack) into individual battery modules (e.g., 10-40+ modules / pack) that are electrically connected in series or parallel and mounted on the vehicle chassis, for example, by a battery pack housing or a carrier plate.On the battery side of the high-voltage network, a DC-DC converter is electrically connected to the traction battery(ies) to boost the voltage supply to a main DC bus and a power inverter module (PIM). A high-frequency large-capacity capacitor can be placed between the positive and negative terminals of the main DC bus to ensure electrical stability and store additional electrical energy. A dedicated electronic battery control module (EBCM), in conjunction with a powertrain control module (PCM) and the power electronics of each motor, controls the operation of the battery pack(s) and the traction motor(s).

[0006] A battery assembly, such as a battery module, battery pack, etc., typically comprises a large number of battery cells positioned relatively close together. Batteries can be broadly divided into primary and secondary batteries. Primary batteries, also known as disposable batteries, are designed to be used until they are depleted and then simply replaced with new ones. Secondary batteries, commonly referred to as rechargeable batteries, utilize a special chemistry that allows them to be repeatedly recharged and reused, offering economic, environmental, and user-friendliness advantages compared to disposable batteries.

[0007] Rechargeable batteries can be used to power items as diverse as toys, consumer electronics, motor vehicles, and aircraft. Certain chemistry components of rechargeable batteries, such as lithium-ion cells, as well as external factors, can cause internal chemical reactions that generate significant amounts of heat energy. Such abnormal chemical reactions can cause the battery cell to generate more heat than it effectively dissipates. If a battery cell is exposed to elevated temperatures for an extended period, it can experience thermal runaway. Accordingly, thermal runaway transmission (TRT) can occur.Thermal unaway propagation (TRP), which begins in a single cell, causes heat to spread to neighboring cells in the battery assembly, and thermal runaway affects the entire battery pack and nearby temperature-sensitive components such as control units, sensors, battery terminals and connectors, etc.

[0008] The individual cells of a lithium-ion battery pack can generate a significant amount of heat during charge and discharge cycles. This cell heat is primarily generated by exothermic chemical reactions and losses due to activation energy, chemical transport, and resistance to ion migration. In lithium-ion batteries, a number of exothermic and gas-generating reactions can occur as cell temperatures rise, potentially leading to an unstable state within the battery assembly. If left unchecked, such thermal events can result in an accelerated, heat-generating state known as thermal runaway (TR) or thermal runaway propagation (TRP), a condition in which the battery system is unable to return the internal battery components to normal operating temperatures.Battery modules consisting of multiple battery cells can be supported by an actively cooled lower cooling plate to control temperatures during the charging and discharging process.

[0009] DE 10 2009 046 801 A1 describes a battery cell whose body has a base, a top, and at least one side surface arranged perpendicular to the base, wherein the maximum extent of the base is greater than the height of the battery cell body defined by the side surface, and the battery cell has terminals assigned to the respective battery cell poles, the terminals being arranged on at least one side surface of the battery cell. DE 10 2009 046 801 A1 further describes a battery with a plurality of battery cells according to the invention, wherein the battery cells, forming the battery pack, are arranged such that their battery poles are located on at least one side surface of the battery cell pack.

[0010] US 2007 / 0009792A1 describes a battery with an electrode assembly comprising first and second electrodes, a terminal element electrically connected to the first electrode, and an external terminal electrically connected to the terminal element, wherein the terminal element includes a fastening element configured to hold the terminal element against the first electrode.

[0011] The object of the present invention is to provide a prismatic battery with which temperature control during charging and discharging processes is improved.

[0012] This problem is solved according to the invention with a prismatic battery comprising the features of claim 1. The present description teaches an improved mechanical design of a rechargeable battery cell (e.g., a lithium-ion battery) for use in electric vehicles and other electrically powered devices. The improved design uses a thermally conductive insert to divide the battery cell into one or more adjacent volumes containing the stacked layers of a battery cell. This thermally conductive insert conducts heat from the center of the battery cell during charging to actively cooled channels arranged in a pair of cooling distributors located on opposite vertical sides of the battery cell, and / or to an actively cooled bottom cooling plate. The pair of stacked battery layers can each be wound in a jelly-roll geometry (electrode winding geometry).The thermally conductive insert can be made of aluminum, an aluminum alloy, copper, or a copper alloy, as well as combinations thereof. The thermally conductive insert is approximately 1 mm thick.

[0013] A prismatic battery according to the invention comprises a prismatic battery housing with a vertical Z-direction aligned along a height of the prismatic battery housing and a horizontal Y-direction aligned along a width of the prismatic battery housing. The battery housing includes a thermally conductive insert arranged inside the prismatic battery housing. The thermally conductive insert defines a first empty volume inside the prismatic battery housing, located on the first side of the thermally conductive insert. The thermally conductive insert also defines a second empty volume arranged inside the prismatic battery housing and located on the second side of the thermally conductive insert.

[0014] Furthermore, the prismatic battery comprises a first and a second cooling distributor and / or a lower cooling plate and / or a top cooling distributor and / or a coolant housing. The first cooling distributor is thermally connected to a first vertical side of the prismatic battery box via a first plurality of cooling channels, and the second cooling distributor is thermally connected to a second plurality of cooling channels via an opposite, second vertical side of the prismatic battery box; the actively cooled lower cooling plate with a plurality of cooling channels is arranged below the prismatic battery box; the top cooling distributor with a plurality of cooling channels is thermally coupled to the top of the prismatic battery box.and the sealed coolant housing contains a coolant that completely surrounds the prismatic battery housing and electrode terminals on all sides with a flowing bath of coolant, wherein the coolant is selected from the group consisting of hydrofluoroethers, hydrocarbons, esters, silicone oils, water / glycol mixtures, hydrofluoroether-based liquids, fluorocarbon-based liquids, and combinations thereof. In some embodiments, the thermally conductive insert is arranged in the center of the prismatic battery housing.

[0015] In some embodiments, the thermally conductive insert consists of a thermally conductive metal selected from aluminium, an aluminium alloy, copper, or a copper alloy, and combinations thereof.

[0016] In some embodiments, the prismatic battery further comprises: a first set of battery layers arranged within the first volume in the prismatic battery box; and a second set of battery layers arranged within the second volume in the prismatic battery box.

[0017] In some embodiments, the prismatic battery includes a lithium-ion battery.

[0018] In some embodiments, the first set of battery layers and the second set of battery layers are wound in a “jelly roll” geometry.

[0019] In some embodiments, the heat-conducting insert has a thickness of 0.2 mm to 1.2 mm.

[0020] In some embodiments, the heat-conducting insert has a thickness of 0.8 mm.

[0021] In some embodiments, the prismatic battery can comprises a pair of outer can walls aligned parallel to a plane of the heat-conducting insert.

[0022] In some embodiments, the heat-conducting insert is aligned parallel to a plane defined by the vertical Z-direction and the horizontal Y-direction.

[0023] In some embodiments, the heat-conducting insert is welded to the prismatic battery box.

[0024] In some embodiments, the heat-conducting insert is extruded simultaneously with the prismatic battery box.

[0025] In some embodiments, the first set of battery layers and the second set of battery layers comprise a negative current collector layer. An anode electrode layer is located adjacent to the negative current collector layer. A separator layer is located adjacent to the anode electrode layer. A cathode electrode layer is located adjacent to the separator layer and opposite the anode electrode layer. A positive current collector layer is located next to the cathode electrode layer.

[0026] In some embodiments, the prismatic battery comprises a lithium-ion battery. The negative current collector layer contains copper. The anode electrode layer contains a material selected from: graphite, lithium titanate, silicon / carbon alloy, or tin / cobalt alloy, or combinations thereof. The separator layer contains a microporous polyolefin polymer selected from: microporous polyethylene (PE), microporous polypropylene (PP), or microporous polyethylene terephthalate (PET), and combinations thereof. The cathode electrode layer contains a compound selected from: lithium metal oxides, LiCoO₂ (LCO), LiMn₂O₄ (LMO), LiFePO₄ (LFP), nickel-manganese-cobalt oxide (NMC), or nickel-cobalt-aluminum oxide (NCA), and combinations thereof. The positive current collector layer contains aluminum.

[0027] In some embodiments, the prismatic battery further comprises: a first electrode terminal located on top of the first set of battery layers; a second electrode terminal located on top of the second set of battery layers; a current collector plate bridging the pair of first and second electrode terminals and being electrically connected to them; an electrical terminal located on top of the current collector plate; the current collector plate being welded to the first electrode terminal; the current collector plate being welded to the second electrode terminal; and an electrical terminal attached to and electrically connected to the current collector plate.

[0028] In some embodiments, a prismatic battery comprises a prismatic battery housing. The prismatic thermally conductive insert is located inside the prismatic battery housing. This insert defines a first volume inside the prismatic battery housing, located on a first side of the thermally conductive insert. The insert also defines a second volume located inside the prismatic battery housing, situated on a second side of the thermally conductive insert.

[0029] In some embodiments, the prismatic battery further comprises a first electrode terminal located on a first side of the prismatic battery housing. A second electrode terminal is located on a second side of the prismatic battery housing; and the first side of the prismatic battery housing is different from the second side of the prismatic battery housing. There are no electrode terminals on the top of the prismatic battery housing.

[0030] In some embodiments, an electric motor vehicle comprises: a vehicle body with a passenger compartment, several road wheels attached to the vehicle body, and a traction motor attached to the vehicle body that drives one or more of the several road wheels to propel the electric motor vehicle. A traction battery pack is attached to the vehicle body and electrically connected to the traction motor. The traction battery pack comprises a plurality of prismatic battery cells arranged in parallel rows. The multiple prismatic battery cells comprise a prismatic battery can and a thermally conductive insert located inside the prismatic battery can. The thermally conductive insert defines a first volume inside the prismatic battery can, located on a first side of the thermally conductive insert.A second volume is located inside the prismatic battery box, situated on a second side of the thermally conductive insert. A first set of lithium-ion battery layers is located within this first volume in the prismatic battery box. A second set of lithium-ion battery layers is located within this second volume in the prismatic battery box.

[0031] In some embodiments, the thermally conductive insert consists of a thermally conductive metal selected from aluminium, an aluminium alloy, copper, or a copper alloy, and combinations thereof.

[0032] In some embodiments, the prismatic battery box also includes a cooling distributor with a plurality of cooling channels, which is thermally coupled to the top of the prismatic battery box.

[0033] In some embodiments, the prismatic battery includes a sealed cooling housing with a coolant inlet and outlet that completely encloses the prismatic battery housing. This allows for immersion cooling of the prismatic battery. Fig. Figure 1 shows a schematic perspective view of an example of a prismatic battery cell with active cooling channels arranged at each end of the battery cell according to the present description. Fig. Figure 2 shows a schematic cross-sectional view (SECTION AA) of an example of a prismatic jelly roll battery cell of width = A with active cooling channels arranged at each end of the battery cell according to the present description. Fig. Figure 3 shows a schematic cross-sectional view (SECTION AA) of an example of two half-sized prismatic jelly roll battery cells of width = A / 2, with active cooling channels at each end of the battery cell and a thermally conductive insert as described herein. Fig. Figure 4 shows an example of the calculated 2D temperature contours of a battery being charged for time = 500 seconds, for four different battery designs, each with a different thickness T of a thermally conductive insert according to the present description. Fig. Figure 5 shows a summary comparison graph of the calculated maximum (e.g., peak) charging temperatures at the top of the battery cell at a time of 500 seconds for the four different [various types]. Fig. 4 designs mentioned in the present description. Fig. Figure 6 shows a schematic perspective view of an example of an electric vehicle with a lithium-ion battery pack according to the present description. Fig. Figure 7 shows a schematic perspective view of an example of a prismatic battery cell with cooling channels arranged in an actively cooled lower cooling plate located at a lower end of the battery cell, according to the present description. Fig. Figure 8A shows a cross-sectional view (SECTION BB) of an example of two half-sized prismatic jelly roll battery cells of width = B / 2 with lateral cooling and a thermally conductive insert according to the present description. Fig. Figure 8B shows a schematic cross-sectional view (SECTION CC) of an example of a prismatic battery box with a heat-conducting insert and a pair of lateral cooling distributors according to the present description. Fig. Figure 8C shows a cross-sectional view (SECTION DD) of an example of two half-sized prismatic jelly roll battery cells of width = B / 2, supported by an actively cooled base plate and incorporating a thermally conductive insert as described herein. Fig. Figure 9 shows a cross-sectional view (SECTION AA) of an example of an empty battery box with a thermally conductive insert which is connected to the battery box by a weld according to the present description. Fig. Figure 10 shows a cross-sectional view (SECTION AA) of an example of an empty battery box with a thermally conductive insert extruded according to the present description. Fig. Figure 11 shows a cross-sectional view (SECTION DD) of an example of an empty battery box with a thermally conductive insert extruded according to the present description. Fig. Figure 12 shows a cross-section (SECTION AA) of an example of a prismatic battery box with a thermally conductive insert according to the present description. Fig. Figure 13 shows a schematic, perspective sectional view (SECTION BB) of an example of a prismatic battery box with a heat-conducting insert arranged inside the prismatic battery box according to the present invention. Fig. Figure 14 shows a cross-section (SECTION BB) of an example of a prismatic battery box with a thermally conductive insert arranged inside the prismatic battery box, according to the present description. Fig. Figure 15 shows a schematic cross-sectional view of an example of five stacked layers of a lithium-ion battery according to the present description. Fig. Figure 16 shows a schematic perspective view of an example of a prismatic battery box with positive and negative electrode terminals on the side walls of the prismatic battery box according to the present description. Fig. Figure 17 shows a schematic view of an example of a prismatic battery box with top cooling and a heat-conducting insert according to the present description. Fig. Figure 18 shows a schematic view of a prismatic battery box with immersion cooling and a heat-conducting insert according to the present description.

[0034] The terms "battery cell," "battery can," "battery casing," and "prismatic can" are used synonymously. A "battery module" is defined as two or more individual battery cells combined in a single battery module. A "battery pack" is defined as two or more individual battery modules combined to form a single battery pack. The term "battery module" or "battery pack" refers to a plurality of prismatic battery cans stacked side by side and arranged parallel to each other in a battery module / pack. The terms "insert," "layer," and "layer" are used interchangeably, as they all refer to a thermally conductive insert.

[0035] Fig. Figure 1 shows a schematic perspective view of an example of a prismatic battery 10 with a plurality of active cooling channels 14, 14' arranged in cooling distributors 12, 12' located on opposite sides of the battery box 23, as described herein. The battery 10 is housed in a prismatic (i.e., rectangular) battery box 23 and has a pair of electrode terminals 16 and 16' on the top plate and top surface 54, respectively, of the battery box 23. On each side of the battery box 23, a pair of cooling distributors 12 and 12' is arranged, each having a plurality of cooling channels 14, 14', etc., carrying a coolant 18 or 18' flowing in the "X" direction.

[0036] Fig. Figure 2 shows a schematic cross-sectional view (SECTION AA) of an example of a prismatic “jelly roll” battery cell 22 with width = A (in the “X” direction), with active cooling distributors 12, 12' arranged at each end of the battery box 23 and containing coolant 18, 18' flowing in cooling channels 14, 14', as described herein. The stacked (wound) battery layers 24 of the battery cell 22 are wound in a jelly roll geometry.

[0037] Fig. Figure 3 shows a schematic cross-sectional view (SECTION AA) of an example of two half-size prismatic jelly roll battery cells 26, 26' with a width = A / 2 (in the "X" direction), with active cooling channels 14, 14' arranged on the proximal and distal vertical sides of the battery cells 26, 26', respectively, and with a thermally conductive insert 30 arranged inside the battery housing 23, as described herein. In some embodiments, the thermally conductive insert 30 is located in the center of the battery housing 23. The thermally conductive insert 30 is located inside the prismatic battery housing 23. The prismatic battery housing 23 defines a first volume 48 located on a first side of the thermally conductive insert 30 and a second volume 48' located on a second side of the thermally conductive insert 30.The thermally conductive insert 30 conducts heat from the center of the battery box 23 to the cooling channels 14, 14' in the cooling distributor 12, 12'. The thermally conductive insert 30 can be made of a material suitable for the application with high thermal conductivity, e.g., aluminum, an aluminum alloy, copper, or a copper alloy, and combinations thereof. In this embodiment, the YZ plane of the thermally conductive insert 30 is aligned parallel to the YZ plane of the battery box 23.

[0038] The prismatic battery can 23 has a vertical Z-direction running along its height and a horizontal Y-direction running along its width. The thermally conductive insert 30 has a wide plane aligned parallel to a plane defined by the vertical Z-direction and the horizontal Y-direction. The stacked battery layers 28 and 28' of the battery cell 26 and 26', respectively, are wound in a geometric "jelly roll" configuration.

[0039] Fig. Figure 4 shows four examples of finite element-calculated 2D temperature contours of a lithium-ion battery cell being charged at time 500 seconds for four different battery designs, each with a different thickness T of the thermally conductive insert 30 as disclosed herein. The thicker the thermally conductive insert 30 (e.g., made of aluminum), the better the heat conduction to the cooling plates (at the cost of a lower battery energy density). The thickest thermally conductive insert 30 (e.g., T = 0.8 mm) exhibits a maximum temperature of 50.1 °C at t = 500 seconds, compared to a maximum temperature of 53.0 °C with a thickness T = 0 mm (i.e., no thermally conductive insert).

[0040] Fig. Figure 5 shows a summary comparison diagram of the calculated maximum (e.g., peak) charging temperatures at the top of the battery cell at a time of 500 seconds for the four different versions of a thermally conductive aluminum insert 30, which are described in Fig. 4. Reference is made to the present description. The x-axis is labelled at point 501, the y-axis at point 502. The maximum temperature decreases from 53.0 °C to 50.1 °C when the thickness of the thermally conductive insert 30 increases from 0 mm to 0.8 mm. The thickness of the thermally conductive insert 30 can range between 0.2 mm and 1.2 mm. However, the thicker the thermally conductive insert 30, the lower the energy density of the battery pack. Therefore, there is a trade-off between the maximum battery temperature and the energy density of the battery cell, depending on the thickness used for the thermally conductive insert 30.

[0041] Fig. Figure 6 shows a schematic perspective view of an example of an electric motor vehicle with a battery pack 4, as described herein. The electric motor vehicle 1 comprises a vehicle body 2, a passenger compartment 5 located within the vehicle body 2, a plurality of road wheels 3, 3', etc., attached to the vehicle body 2, and a battery pack 4 located within the electric motor vehicle 1. The electric motor vehicle 1 also comprises one or more electric traction motors 13 attached to the vehicle body 2, which drive one or more of the road wheels 3, 3', etc., propelling the electric motor vehicle 1. The battery pack 4 is physically attached to the vehicle body 2 and electrically connected to the traction motor(s) 13 via an electrical cable 15.

[0042] Fig. Figure 7 shows a schematic perspective view of an example of a prismatic battery box 23 with cooling channels 14, 14' arranged in an actively cooled bottom cooling plate, the lower cooling plate 60, which supports the battery 10, according to the present description. The coolant 18 flows through parallel cooling channels 14, 14', etc. in the X direction. The side walls 42 and 42' are labeled.

[0043] Fig. Figure 8A shows a cross-sectional view (SECTION BB) of an example of two half-sized prismatic jelly roll battery cells 32, 32' of width = B / 2, with side cooling and including a thermally conductive insert 30, according to the present description. The side cooling (not shown in this view) can be used in this embodiment. The wide plane of the thermally conductive insert 30 is aligned parallel to the YZ plane. Electrode terminals 61 and 61' are located on the top side of each battery cell 32 and 32', respectively. The horizontal current collector plate 64 extends over both electrode terminals 61 and 61', and the current collector plate 64 is attached to the electrode terminals 61 and 61' by welds 62 and 62'. An electrical terminal 66 is located on the top side of the battery box 23 for making an electrical connection to the current collector plate 64. Fig. Figure 13 shows a close-up of the top of the battery box 23. Due to the use of the electrode terminals 61, 61', the welds 62, and the current collector plate 64, it is not possible to extend the thermally conductive insert 30 all the way to the top of the prismatic battery box 23. For this reason, the vertical extension of the thermally conductive insert 30 ends just before point 70 and does not extend to the top 54 of the prismatic battery box 23.

[0044] As in Fig. As shown in Figure 8A, in some embodiments the lower end 71 of the thermally conductive insert 30 is not connected to the lower wall 52 of the prismatic battery box 23. In this embodiment, it is sufficient if the thermally conductive insert 30 is connected only to the side walls 42 and 42' of the prismatic battery box 23 (i.e., when side cooling is used, as in Figure 8A). Fig. 1, Fig. 7 and Fig. 8B shown).

[0045] Fig. Figure 8B shows a schematic cross-sectional view (SECTION CC) of an example of a prismatic battery box 23 with a thermally conductive insert 30 and lateral cooling distributors 12 and 12' or cooling channels 14 and 14, respectively, according to the present description. The thermally conductive insert 30 is attached to the side walls 42 and 42' of the prismatic battery box 23 (e.g., by welding or extrusion). In this embodiment, however, the upper and lower parts 70 and 71, respectively, of the thermally conductive insert 30 are not attached to the upper and lower walls 54 and 52, respectively, of the prismatic battery box 23 (i.e., because the upper and lower walls 54 and 52 are not actively cooled in this embodiment, which uses side cooling).

[0046] Fig. Figure 8C shows a cross-sectional view (SECTION DD) of an example of two half-sized prismatic jelly roll battery cells 32, 32' with a total width = B, with a thermally conductive insert 30 arranged inside battery box walls 36, 36', 42 and 42', as described herein. The cooling channels 14, 14', etc. are arranged in a thermally coupled, actively cooled bottom cooling plate, the lower cooling plate 60, which supports the battery box 23. The coolant 18 flows in the X direction within the cooling channels 14, 14', etc. The plane of the thermally conductive insert 30 is aligned parallel to the YZ plane. Electrode terminals 61 and 61' are located on the top of each battery cell 32 and 32', respectively. The horizontal current collector plate 64 extends over both electrode terminals 61 and 61', and the current collector plate 64 is attached to the electrode terminals 61 and 61' respectively by welds 62 and 62'.An electrical connection 66 is located on the top of the battery box 23 for establishing an electrical connection to the current collector plate 64. Fig. Figure 13 shows a close-up of the top of the battery box 23. Due to the use of the electrode terminals 61, 61', the welds 62, and the current collector plate 64, it is not possible to extend the thermally conductive insert 30 all the way to the top of the prismatic battery box 23. For this reason, the vertical extension of the thermally conductive insert 30 ends just before point 70 and does not reach the top 54 of the prismatic battery box 23.

[0047] Fig. Figure 9 shows a cross-sectional view (SECTION AA) of an example of an empty battery box 23 with a thermally conductive insert 30 of thickness = T, which is welded to the proximal side wall 42 and the distal side wall 42' of the battery box 23 by two line welds 40 and 40' respectively, as described herein. The empty volumes 48, 48' are filled with a pair of battery cells half the size (not shown).

[0048] Fig. Figure 10 shows a cross-sectional view (SECTION AA) of an example of an empty battery can 23 with proximal and distal sidewalls 42 and 42' respectively, and with a thermally conductive insert 30 of thickness = T, all co-extruded as a single monolithic extrusion, and a pair of sidewalls 20, 20', as described herein. The empty volumes 48, 48' are bounded by the sidewalls 20 or 20' and the end-face sidewalls 42, 42' and the thermally conductive insert 30, and are finally filled with a pair of battery cells half the size (not shown).

[0049] Fig. Figure 11 shows a cross-sectional view (SECTION DD) of an example of an empty battery box 23 with a pair of side walls 20, 20' and a thermally conductive insert 30 with a thickness = T, which is welded to the lower wall 52 of the battery box 23 by a weld 40, as described herein. The empty volumes 50, 50' are bounded by the side walls 20 or 20' and the end walls 42, 42' (not shown) and the thermally conductive insert 30, and are finally filled with a pair of battery cells half the size (not shown). The thermally conductive insert 30 does not extend vertically to the top of the prismatic battery box 23, but terminates just before the top 54 at point 70. This configuration can be used with bottom cooling, as in Fig. 7 shown.

[0050] Fig. Figure 12 shows a cross-section (SECTION AA) of an example of an empty battery box 23 with a thermally conductive insert 30 according to the present description. The thermally conductive insert 30 extends over the entire width of the battery box 23, from the proximal side wall 42 to the distal side wall 42', and the plane of the thermally conductive insert 30 is parallel to the YZ plane. The empty volumes 48, 48' are finally filled with a pair of battery cells half the size (not shown). However, it should be noted that in some embodiments the wall thickness of the side wall 20 or 20' may be the same as or different from the wall thickness of the thermally conductive insert 30.

[0051] Fig. Figure 13 shows a schematic, perspective sectional view (SECTION BB) of an example of a prismatic battery box 23 with a thermally conductive insert 30 arranged inside the prismatic battery box 23 according to the present invention. The thermally conductive insert 30 defines a pair of empty volumes 48 and 48' on each side of the insert 30 within the prismatic battery box 23. The thermally conductive insert 30 does not extend vertically to the top 54 of the prismatic battery box 23, but terminates at position 70 (to provide space for internal electrical connections to external electrical terminals 16').

[0052] Fig. Figure 14 shows a cross-section (section BB) of an example of a prismatic battery box 23 with a thermally conductive insert 30 as described herein. The thermally conductive insert 30 extends vertically almost over the entire height H of the battery box 23, from the lower wall 52 (i.e., the base plate) to near the top 54 (i.e., the cover plate). The wide plane of the thermally conductive insert 30 is parallel to the YZ plane. Electrode terminals 61 and 61' are located on the top of each battery cell 32 and 32', respectively. The horizontal current collector plate 64 extends over both electrode terminals 61 and 61', and the current collector plate 64 is attached to the electrode terminals 61 and 61' by welds 62 and 62'. An electrical terminal 66 is located on the top of the battery box 23 to provide an electrical connection to the current collector plate 64.The thermally conductive insert 30 does not extend vertically to the top 54 of the prismatic battery box 23, but ends at point 70 (to make room for internal electrical connections with the external electrical connection 16').

[0053] Fig. Figure 15 shows a schematic cross-sectional view of an example of a five-layer lithium-ion battery 19 according to the present description. The five battery layers of the lithium-ion battery 19 comprise: a negative current collector layer 11, an anode electrode layer 6 arranged adjacent to the negative current collector layer 11, a separator layer 7 arranged adjacent to the anode electrode layer 6, a cathode electrode layer 8 arranged adjacent to the separator layer 7 and opposite the anode electrode layer 6, and a positive current collector layer 9 arranged adjacent to the cathode electrode layer 8. The negative current collector layer 11 can consist of a copper sheet. The anode electrode layer 6 can consist of a material selected from: graphite, lithium titanate, silicon / carbon or tin / cobalt alloy, and combinations thereof.The separator layer 7 can comprise a microporous polyolefin polymer selected from: microporous polyethylene (PE), microporous polypropylene (PP), or microporous polyethylene terephthalate (PET), and combinations thereof. The cathode electrode layer 8 can consist of a compound selected from: lithium metal oxides, 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 can consist of aluminum.

[0054] Fig. Figure 16 shows a schematic perspective view of an example of a prismatic battery box 23 with positive and negative electrode terminals 90 and 92, respectively, arranged on the side walls 20 and 42 of the battery box 23, according to the present description. In this embodiment, no electrode terminals are arranged on the top surface 54 of the battery box 23.

[0055] In some embodiments, more than one (i.e., several) thermally conductive insert(s) 30 can be used in each prismatic battery box 23.

[0056] Fig. Figure 17 shows a schematic view of a prismatic battery box 23 with top cooling and a thermally conductive insert 30 as described herein. In some embodiments, the top surface 54 of the prismatic battery box 23 is actively cooled. This top-top cooling scheme includes a top-top coolant distributor 100 with a plurality of cooling channels 102, 102', etc., arranged within the top-top coolant distributor 100. In this embodiment, the thermally conductive insert 30 is attached (e.g., welded) only to the top surface 54 of the prismatic battery box 23 and not to the side walls 42, 42', or the bottom wall 52. Optionally, the thermally conductive insert 30 can also be attached to some or all of the walls of the prismatic battery box 23.

[0057] In some embodiments, the various active cooling schemes (e.g., side cooling on two sides, bottom cooling, and top cooling) can be combined in various ways to cool a prismatic battery, including but not limited to: 1. Side cooling only; 2. Cooling from below only; 3. Cooling from above only; 4. Lateral and lower cooling; 5. Lateral and top cooling; 6. Cooling from below and above; and 7. Lateral, lower and upper cooling.

[0058] Fig. Figure 18 shows a schematic view of a prismatic battery box 23, which is cooled by immersion, with a thermally conductive insert 30, as described herein. Immersion cooling is achieved by enclosing the prismatic battery box in a sealed coolant housing 110 containing coolant 116 (which can be a dielectric coolant, such as hydrofluoroethers, hydrocarbons, esters, silicone oils, water / glycol mixtures, hydrofluoroether-based liquids, fluorocarbon-based liquids, and combinations thereof). The coolant 116 completely surrounds the prismatic battery box 23 and the electrode terminals 16 and 16' on all sides with a flowing bath of coolant 116. The coolant 116 is introduced into and removed from the sealed coolant housing 110 via the coolant inlet 112 and the coolant outlet 114, respectively.For immersion cooling, the thermally conductive insert 30 can be connected to at least one surface of the prismatic battery box 23, with connection to multiple surfaces being better.

[0059] In some embodiments, the coolant is not circulated around the prismatic battery box 23 (see also Fig. 18). Rather, the prismatic battery box 23 is located in a stationary, non-circulating bath of coolant. In this case, there would only be one filling opening (not shown) on the upper coolant housing 110, through which the coolant housing 110 is filled with coolant 116.

Claims

[1] Prismatic battery (10) comprising: a prismatic battery box (23) with a vertical Z-direction aligned along a height of the prismatic battery box (23) and a horizontal Y-direction aligned along a width of the prismatic battery box (23); and a thermally conductive insert (30) which is arranged inside the prismatic battery box (23) and defines a first volume (48) inside the prismatic battery box (23), wherein the first volume (48) is arranged on a first side of the thermally conductive insert (30), and which defines a second volume (48') inside the prismatic battery box (23), wherein the second volume (48') is arranged on a second side of the thermally conductive insert (30); characterized by , that the prismatic battery (10) further comprises: a first and a second cooling distributor (12, 12') and / or a lower cooling plate (60) and / or a top cooling distributor (100) and / or a cooling housing (110); wherein the first cooling distributor (12) is thermally connected to a first plurality of cooling channels (14) with a first vertical side of the prismatic battery box (23) and the second cooling distributor (12') is thermally connected to a second plurality of cooling channels (14') with an opposite, second vertical side of the prismatic battery box (23); wherein the actively cooled lower cooling plate (60) with a plurality of cooling channels (14, 14') is arranged below the prismatic battery box (23); wherein the top-side coolant distributor (100) is thermally coupled to a plurality of cooling channels (102, 102') with the top (54) of the prismatic battery box (23); and wherein the sealed coolant housing (110) carries a coolant (116) which completely surrounds the prismatic battery box (23) and electrode terminals (16, 16') on all sides with a flowing bath of coolant (116), wherein the coolant (116) is selected from the group consisting of hydrofluoroethers, hydrocarbons, esters, silicone oils, water / glycol mixtures, hydrofluoroether-based liquids, fluorocarbon-based liquids and combinations thereof. [2] Prismatic battery (10) according to claim 1, wherein the thermally conductive insert (30) consists of a thermally conductive metal selected from aluminium, an aluminium alloy, copper, or a copper alloy, or combinations thereof. [3] Prismatic battery (10) according to claim 1, further comprising: a first set of battery layers arranged within the first volume (48) in the prismatic battery box (23); and a second set of battery layers arranged within the second volume (48') in the prismatic battery box (23). [4] Prismatic battery (10) according to claim 3, wherein the prismatic battery (10) comprises a lithium-ion battery (19). [5] Prismatic battery (10) according to claim 3, 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] Prismatic battery (10) according to claim 1, wherein the thermally conductive insert (30) has a thickness (T) in the range of 0.2 mm to 1.2 mm. [7] Prismatic battery (10) according to claim 1, wherein the prismatic battery box (23) comprises a pair of outer side walls (20, 20') aligned parallel to a plane of the heat-conducting insert (30). [8] Prismatic battery (10) according to claim 1, wherein the thermally conductive insert (30) is welded to the prismatic battery box (23). [9] Prismatic battery (10) according to claim 1, wherein the thermally conductive insert (30) is extruded simultaneously with the extrusion of the prismatic battery box (23). [10] Prismatic battery (10) according to claim 3, wherein the first set of battery layers comprises five layers, including: a negative current collector layer (11); an anode electrode layer (6) which is arranged adjacent to the negative current collector layer (11); a separator layer (7) which is arranged adjacent to the anode electrode layer (6); a cathode electrode layer (8) which is arranged adjacent to the separator layer (7) and opposite the anode electrode layer (6); and a positive current collector layer (9) which is arranged adjacent to the cathode electrode layer (8).

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