DE102022111482A1 - Battery arrangement - Google Patents

Abstract

A battery arrangement (20) has at least one battery module (30) with a battery module housing (70), battery cells (36), a coolant (60) and capillary arrangements (40), which battery module housing (70) defines a battery module interior (34), in which Battery module interior (34), the battery cells (36), the coolant (60) and the capillary arrangements (40) are arranged, which capillary arrangements (40) have a first material (41), are at least partially arranged at least in sections between the battery cells (36) and are designed to enable a fluid flow of the refrigerant (60), which battery module housing (70) has a first wall (71) and a second wall (72), which first wall (71) is arranged at least in sections above the battery cells (36). which second wall (72) is arranged at least in sections below the battery cells (36), which battery cells (36) have a layer (61) made of a first material at least partially on at least one battery cell side (62) facing the adjacent capillary arrangement (40), which first material has aramids.

Description

The invention relates to a battery arrangement and a vehicle with a battery arrangement.

The CN 211 295 207 U shows a battery with several battery cells and a phase change element.

The WO 2019 / 231 202 A1 shows a cooling device for cooling a battery.

The US 2020 / 038 810 A1 shows a battery with several battery cells and foamed intermediate elements.

It is therefore an object of the invention to provide a new battery arrangement and a new vehicle.

This task is solved by the subject matter of the independent claims.

A battery arrangement has at least one battery module with a battery module housing, battery cells, a coolant and capillary arrangements, which battery module housing defines a battery module interior, in which battery module interior the battery cells, the coolant and the capillary arrangements are arranged, which capillary arrangements have a first material, at least partially at least in sections between the battery cells are arranged and are set up to enable a fluid flow of the refrigerant, which battery module housing has a first wall and a second wall, which first wall is arranged at least in sections above the battery cells, which second wall is arranged at least in sections below the battery cells, which Battery cells at least partially have a layer made of a first material on at least one battery cell side facing the adjacent capillary arrangement, which first material has aramids. Aramids have high strength and can distribute local pressure over a large area. This can reduce the risk of damage to the battery cells caused by differential pressure.

According to a preferred embodiment, the first material has aramid fibers. Aramid fibers are well suited to distributing local force across a surface.

According to a preferred embodiment, the first material has p-aramid fibers and/or p-aramid copolymer fibers. These fibers have proven to be particularly stable and suitable.

• - Kevlar,
• - Twaron, oder
• - Technora

auf. Diese am Markt erhältlichen Aramide sind sehr gut als Schicht geeignet.According to a preferred embodiment, the first material

• - Kevlar,
• - Twaron, or
• - Technora

on. These aramids available on the market are very suitable as a layer.

According to a preferred embodiment, the battery cells are coated with the first material. This results in a good bond between the battery cell and the first material, and slipping of the first material is prevented.

According to a preferred embodiment, the first material is at least partially open-pored or has open channels. The open-pored design or the open channels enable good transport of the refrigerant within the capillary arrangement

According to a preferred embodiment, the first material is designed to be open-pored at least in some areas. The open-porous design enables good transport of the refrigerant within the capillary arrangement and, if necessary, a transfer of the refrigerant into fluid channels.

• - die erste Wand,
• - die zweite Wand, oder
• - die erste Wand und die zweite Wand

zumindest abschnittsweise zu kühlen, um dort eine Kondensation des Kältemittels zu ermöglichen. Die erste Wand und/oder zweite Wand können hierdurch als effektive Kondensationsflächen wirken. Die erste Wand ist vorteilhaft, da das verdampfte Kältemittel durch die geringe Dichte nach oben transportiert wird und nach der Kondensation direkt im oberen Bereich und auch im unteren Bereich die Batteriezellen kühlen kann.According to a preferred embodiment, the battery arrangement has at least one cooling element, which at least one cooling element is set up to

• - the first wall,
• - the second wall, or
• - the first wall and the second wall

to cool at least in sections in order to enable condensation of the refrigerant there. The first wall and/or second wall can thereby act as effective condensation surfaces. The first wall is advantageous because the evaporated refrigerant is transported upwards due to the low density and, after condensation, can cool the battery cells directly in the upper area and also in the lower area.

According to a preferred embodiment, the absolute pressure in the battery module housing at 20 ° C is lower than 1.0 bar in order to reduce the evaporation temperature of the refrigerant compared to an absolute pressure of 1.0 bar. The refrigerant works particularly effectively when it switches back and forth between the liquid and gaseous states, and this change is promoted by the low pressure.

According to a preferred embodiment, the absolute pressure in the battery module housing at 20 ° C is between 0.1 bar and 0.8 bar, preferably between 0.2 bar and 0.6 bar, and particularly preferably between 0.3 bar and 0.5 bar. This enables the physical state of the refrigerant to change at comparatively low temperatures.

According to a preferred embodiment, at least one first fluid channel is formed between the battery cells and the battery module housing, via which first fluid channel the battery module interior is in fluid communication between the first wall and the second wall in order to enable a coolant flow through this at least one first fluid channel. In particular, the liquid refrigerant can easily reach the lower area and is available for cooling.

According to a preferred embodiment, the capillary arrangements at least partially have a second fluid channel, via which second fluid channel the battery module interior is in fluid communication between the first wall and the second wall in order to enable a coolant flow through this at least one second fluid channel. Through the second fluid channels, the refrigerant that has evaporated after absorbing the thermal energy can quickly escape from the capillary arrangement and from the area of the battery cells. This also increases the capillary effect of the capillary arrangements. The capillary effect mainly works in the liquid state of the refrigerant.

According to a preferred embodiment, a cavity is provided at least in some areas between the battery cells and the second wall in order to enable accumulation of liquid refrigerant and the formation of a refrigerant sump in this cavity. On the one hand, this enables good cooling even in the lower area, and on the other hand, the refrigerant can be absorbed by the capillary arrangements.

• - Metallschaum,
• - Titanschwamm, und
• - Metallwolle.

According to a preferred embodiment, the first material is selected from a group of materials consisting of:

• - metal foam,
• - titanium sponge, and
• - metal wool.

The first materials mentioned enable very good capillary transport of the refrigerant and thus good cooling performance.

According to a preferred embodiment, the first material has metal foam, which metal foam contains nickel, copper or iron, in particular stainless steel. Metal foam is easy to produce industrially and enables good capillary transport. Nickel, copper or iron, especially stainless steel, enable a stable structure and good production of the metal foam.

According to a preferred embodiment, the metal foam is designed as an anisotropic metal foam with pores, which pores are stretched at least in regions in at least a first direction parallel to the battery cells relative to a second direction perpendicular to the battery cells. This allows the refrigerant to flow easily between the first wall and the second wall.

According to a preferred embodiment, the first material has titanium sponge, which titanium sponge is sintered from titanium sponge powder. Although titanium is an expensive material, it is available comparatively cheaply as titanium sponge powder. In addition, titanium is relatively light and has high strength. Sintered titanium sponge creates a beneficial porous structure.

A vehicle has such a battery arrangement and an electric motor. Such a vehicle enables good cooling of the battery arrangement and thus high performance and a long range.

• 1 in einer schematischen Darstellung eine Batterieanordnung,
• 2 in einem Querschnitt entlang der Linie II - II von 1 eine erste Ausführungsform einer Kapillaranordnung von 1,
• 3 in einem Querschnitt entlang der Linie II - II von 1 eine zweite Ausführungsform einer Kapillaranordnung von 1, und
• 4 ein Fahrzeug mit der Batterieanordnung von 1.

Further details and advantageous developments of the invention result from the exemplary embodiments described below and shown in the drawings, which are in no way to be understood as a limitation of the invention, and from the subclaims. It is understood that the features mentioned above and those to be explained below can be used not only in the combination specified in each case, but also in other combinations or alone, without departing from the scope of the present invention. It shows:

• 1 in a schematic representation of a battery arrangement,
• 2 in a cross section along line II - II of 1 a first embodiment of a capillary arrangement from 1 ,
• 3 in a cross section along line II - II of 1 a second embodiment of a capillary arrangement from 1 , and
• 4 a vehicle with the battery arrangement of 1 .

The following are identical or identically acting parts with the same reference numerals hen and are usually only described once. The description builds on each other across characters in order to avoid unnecessary repetition.

1 shows a battery arrangement 20, which has at least one battery module 30 with a battery module housing 70, battery cells 36, a coolant 60 and capillary arrangements 40.

The battery module housing 70 defines a battery module interior 34, in which battery module interior 34 the battery cells 36, the coolant 60 and the capillary arrangements 40 are arranged.

The capillary arrangements 40 are at least partially arranged at least in sections between the battery cells 36 and are designed to enable a fluid flow of the refrigerant 60.

The battery module housing 70 has a first upper wall 71 and a second lower wall 72. The first wall 71 is arranged at least in sections above the battery cells 36, and the second wall 72 is arranged at least in sections below the battery cells 36.

The battery arrangement 20 has an upper cooling element 51 and a lower cooling element 52, and the cooling elements 51, 52 are designed to cool the first wall 71 and/or the second wall 72 at least in sections in order to enable condensation of the refrigerant 60 there . It is also possible, for example, to provide only the upper cooling element 51 or only the lower cooling element 52, or to effect cooling directly through the battery module housing 70 in cold regions. In the exemplary embodiment, the cooling elements 51, 52 have channels 54 through which a coolant can flow in order to transport away the heat. The cooling elements 51, 52 are designed as cooling plates in the exemplary embodiment.

At least one first fluid channel 43 is preferably formed between the battery cells 36 and the battery module housing 70, and the battery module interior 34 is in fluid communication between the first wall 71 and the second wall 72 via the first fluid channel 43. This enables refrigerant to flow through this at least one first fluid channel 43.

In the lower area, a cavity 75 is preferably provided at least in some areas between the battery cells 36 and the second wall 72 in order to enable an accumulation of liquid refrigerant 60 and the formation of a refrigerant sump in this cavity 75.

The refrigerant 60 can be both liquid and gaseous as a fluid, and by absorbing thermal energy it can change from the liquid to the gaseous state. This allows a comparatively large amount of heat energy to be absorbed and transported away. In the exemplary embodiment, the battery module housing 70 is cuboid-shaped and, in addition to the first wall 71 and second wall 72, it has a left third wall 73 and a right fourth wall 74 as well as front and rear walls (not shown). Other basic shapes of the battery module housing 70 are also possible, for example a cylindrical shape or a spherical shape.

The battery module housing 70 preferably ensures that the coolant 60 cannot escape from the battery module housing 70 or can only escape to a small extent during normal operation. During operation, heat is generated on the battery cells 36, and the liquid refrigerant 60 can absorb this heat and evaporate in the process. This allows the refrigerant 60 to absorb a large amount of thermal energy. The evaporated refrigerant 60 rises, for example, towards the first wall 71 and is cooled there. As a result of the cooling, the refrigerant 60 condenses and can flow downwards via the fluid channels 43. In the lower region of the battery module housing 70, the refrigerant 60 can accumulate and form a refrigerant sump, with the battery cells 36 preferably being at least partially in the refrigerant sump at 20 ° C. The capillary arrangements 40, which are at least partially arranged between the battery cells 36, enable the refrigerant 60 in the battery module housing 70 to rise due to the capillary action. As a result, liquid refrigerant 60 can be provided over a large area in the area between the battery cells 36 and absorb thermal energy there. This increases the cooling capacity of the battery arrangement 20.

The battery cells 36 have at least partially on at least one side facing the adjacent capillary arrangement 40 a layer 61 made of a first material, which has the first material aramide. In the exemplary embodiment, the left battery cell 36 has no layer 61 on the left side, since no adjacent capillary arrangement 40 is provided in this area. Alternatively, a layer 61 can also be provided there. The other battery cells 36 have layer 61 on both sides. Layer 61 can also be provided on all six sides of the battery cells 36.

2 shows an example of a cross section through one of the capillary arrangements 40 and schematically indicated two battery cells 36 with the layers 61. In the exemplary embodiment, the capillary arrangement 40 has areas with a first material 41 which has capillary properties has. In addition, fluid channels 42 are preferably provided, via which the refrigerant 60 can quickly escape from the capillary arrangement 40 in the gaseous state.

The refrigerant 60 is therefore transported upwards in the liquid state by the first material 41 with the capillary properties, and after the absorption of heat and the transition of the refrigerant 60 into the gaseous state, it can be transported via the fluid channels 42 quickly and without great fluid resistance escape at the top or bottom. In the exemplary embodiment, an area with the first material 41 and the capillary action and a fluid channel 42 are always alternately provided.

The first material of the first layers 61 preferably has aramid fibers. Fibers enable good pressure distribution.

The first material preferably has p-aramid fibers. p-aramid fibers are high-strength synthetic fibers with high temperature resistance. These fibers can be obtained in particular under the name Kevlar from DuPont or under license from DuPont or under the name Twaron from Teijin Aramid or under license from Teijin Aramid, and these products are well suited for the layers 61.

The first material preferably has p-aramid copolymer fibers. p-aramid copolymer fibers are high-strength synthetic fibers with high temperature resistance. These fibers can be obtained in particular under the name Technora from Teijin Aramid or under license from Teijin Aramid, and Technora is well suited for layers 61.

When the coolant 60 evaporates, large local pressures can arise, which can lead to damage to the battery cells 36. By providing the layers 61 with the high-strength aramid material, the locally occurring pressure differences can be distributed over a large area and the risk of damage to the battery cells 36 is reduced. This increases the safety of the battery arrangement.

3 shows a further embodiment of the capillary arrangement 40, which has a first layer 81 with a first material 41A and a second layer 82 with a first material 41B, a grid structure 44 being provided between the layers 81, 82 with the first material 41A and 41B is, which forms the fluid channels 42. As a result, the liquid refrigerant 60 can reach the area of the battery cells 36 over a large area, and after evaporation it can escape through the internal fluid channels 42.

The first wall 71 and the second wall 72 are preferably in fluid communication via the fluid channels 42, so a fluid can pass from the first wall 71 to the second wall 72 and flow through the fluid channels 42 at least in sections.

The absolute pressure in the battery module housing 70 is preferably lower than 1.0 bar at 20 ° C in order to reduce the evaporation temperature of the refrigerant 60 compared to an absolute pressure of 1.0 bar. The absolute pressure of 1.0 bar corresponds approximately to a normal pressure outdoors.

The absolute pressure in the battery module housing 70 is preferably between 0.1 bar and 0.8 bar at 20 ° C, more preferably between 0.2 bar and 0.6 bar and particularly preferably between 0.3 bar and 0.5 bar. This enables a low evaporation temperature.

• - Metallschaum,
• - Titanschwamm, und
• - Metallwolle.

The first material 41 with the capillary properties is preferably from the material group consisting of:

• - metal foam,
• - titanium sponge, and
• - metal wool.

These are materials with small structures and therefore good capillary action. The structures can, for example, have widths in the range from 10 nm to a few mm. However, microporous structures with a width of less than 2 nm are also possible. The metal structures mentioned have the advantage that they are comparatively stable and the metal enables good heat conduction. The stability is advantageous, for example, if the battery cells 36 are pressed against each other, as is common, for example, with pouch battery cells.

The first material 41 is preferably at least partially open-pored or open-porous in order to enable a good flow of the refrigerant 60.

Metal foams are available, for example, from the metals nickel, copper, iron and/or metal alloys such as stainless steel. They have good capillary action and can be used, for example, for pouch, round or prism battery cells.

An anisotropic metal foam is preferably used, the pores of which at least partially have a higher expansion in at least one direction than in another direction. Preferably, the stretched pores are positioned such that the stretched pores extend in a direction between the first wall 71 and the second wall 72. Suitable metals or metal alloys include, for example, nickel, nickel alloys and stainless steel. Anisotropic metal foam enables higher cooling performance due to a larger mass flow of the refrigerant 60 in the same installation space.

Open-porous metal foams can be produced, for example, by melt infiltration of placeholder structures. The placeholder structures are removed from the foam structure after the molten metal has solidified. Salt granules, polymer placeholders or sand granules, for example, are used as placeholder structures. Alternatively, the metal foams can be produced by a sintering process.

Sponge titanium is a structure containing titanium or a titanium alloy. Titanium sponge can, for example, be made from titanium sponge powder through a sintering process. Titanium sponge powder is available as a waste product from various manufacturing processes. Titanium sponge enables a large mass flow of the refrigerant 60. Titanium sponge can be used, for example, for pouch, round or prism battery cells.

For example, titanium sponge can be produced using the Kroll process. Here, titanium tetrachloride is reduced with magnesium to form metallic titanium. Magnesium and magnesium chloride are removed.

Metal wool is used in many different ways in technology. It also has a good capillary structure and enables high cooling performance by conveying the coolant 60 between the battery cells 36. Metal wool can be used, for example, for pouch, round or prism battery cells, and its good deformability means it can also be used on curved structures be adjusted, as these occur, for example, with lying or standing round battery cells.

4 shows a vehicle 10 with such a battery arrangement 20, which is schematically connected to an electric motor 14 via an electrical line 12. In vehicles 10, the battery arrangement 20 is particularly advantageous because it enables a good cooling effect and thus also a good range of the vehicle 10.

Naturally, a variety of variations and modifications are possible within the scope of the present invention.

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• CN 211295207 U [0002]
• WO 2019/231202 A1 [0003]
• US 2020/038810 A1 [0004]

Claims (17)

Battery arrangement (20), which has at least one battery module (30) with a battery module housing (70), battery cells (36), a coolant (60) and capillary arrangements (40), which battery module housing (70) defines a battery module interior (34), in which Battery module interior (34), the battery cells (36), the coolant (60) and the capillary arrangements (40) are arranged, which capillary arrangements (40) have a first material (41), are at least partially arranged at least in sections between the battery cells (36) and are designed to enable a fluid flow of the refrigerant (60), which battery module housing (70) has a first wall (71) and a second wall (72), which first wall (71) is arranged at least in sections above the battery cells (36). which second wall (72) is arranged at least in sections below the battery cells (36), which battery cells (36) have a layer (61) made of a first material at least partially on at least one battery cell side (62) facing the adjacent capillary arrangement (40), which first material has aramids. Battery arrangement (20). Claim 1 , in which the first material has aramid fibers. Battery arrangement (20). Claim 1 or 2 , in which the first material has p-aramid fibers or p-aramid copolymer fibers. Battery assembly (20) according to one of the preceding claims, in which the first material - Kevlar, - Twaron, or - Technora has. Battery arrangement (20) according to one of the preceding claims, in which the first material (41) is at least partially open-pored or has open channels. Battery arrangement (20) according to one of the preceding claims, in which the first material (41) is designed to be open-porous at least in some areas. Battery arrangement (20) according to one of the preceding claims, which has at least one cooling element (51, 52), which at least one cooling element (51, 52) is set up to - the first wall (71), - the second wall (72), or - to cool the first wall (71) and the second wall (72) at least in sections in order to enable condensation of the refrigerant (60) there. Battery arrangement (20) according to one of the preceding claims, in which the absolute pressure in the battery module housing (70) at 20 ° C is lower than 1.0 bar in order to increase the evaporation temperature of the refrigerant (60) compared to an absolute pressure of 1.0 bar humiliate. Battery arrangement (20). Claim 8 , at which the absolute pressure in the battery module housing (70) at 20 ° C is between 0.1 bar and 0.8 bar, preferably between 0.2 bar and 0.6 bar, and particularly preferably between 0.3 bar and 0, 5 bar. Battery arrangement (20) according to one of the preceding claims, in which at least a first fluid channel (43) is formed between the battery cells (36) and the battery module housing (70), via which first fluid channel (43) the battery module interior (34) between the first wall (71) and the second wall (72) is in fluid communication to enable refrigerant flow through this at least one first fluid channel (43). Battery arrangement (20) according to one of the preceding claims, in which the capillary arrangements (40) at least partially have a second fluid channel (42), via which second fluid channel (42) the battery module interior (34) between the first wall (71) and the second wall (72) is in fluid communication to enable refrigerant flow through this at least one second fluid channel (42). Battery arrangement (20) according to one of the preceding claims, in which a cavity (75) is provided at least in some areas between the battery cells (36) and the second wall (72) in order to prevent an accumulation of liquid refrigerant (60) in this cavity (75). and to enable the formation of a refrigerant sump. Battery arrangement (20) according to one of the preceding claims, in which the first material (41) is selected from a material group consisting of: - metal foam, - titanium sponge, and - metal wool. Battery arrangement (20) according to one of the preceding claims, in which the first material (41) has metal foam, which metal foam contains nickel, copper or iron, in particular stainless steel. Battery arrangement (20) according to one of the preceding claims, in which the metal foam is designed as an anisotropic metal foam with pores, which pores are stretched at least in regions in at least a first direction parallel to the battery cells (36) relative to a second direction perpendicular to the battery cells ( 36). Battery arrangement (20) according to one of the preceding claims, in which the first material (41) comprises titanium sponge, which titanium sponge is sintered from titanium sponge powder. Vehicle (10), which has a battery arrangement (20) according to one of the preceding claims and an electric motor (14).

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