WO2011035992A1

WO2011035992A1 - Battery system with external baffle coolant

Info

Publication number: WO2011035992A1
Application number: PCT/EP2010/062000
Authority: WO
Inventors: Christian Pankiewitz; Achim Schmidt
Original assignee: Sb Limotive Company Ltd.; Sb Limotive Germany Gmbh
Priority date: 2009-09-25
Filing date: 2010-08-18
Publication date: 2011-03-31
Also published as: EP2481108A1; DE102009045012A1

Abstract

The present invention relates to a battery system with baffle coolant, comprising: i) one or more battery cells; ii) at least one housing in which the battery cells are arranged; iii) a cold plate which is arranged outside the housing; and iv) one or more passive heating conducting means, which is or are arranged such that thermal energy can be transmitted from the battery cells to the cold plate via the passive heat conducting means, characterized in that the battery system has baffle cooling for transmission of thermal energy from the cold plate to a fluid flow, wherein the baffle cooling is designed such that a fluid flow for absorption of thermal energy can be routed substantially at right angles to a surface of the cold plate.

Description

description

title

Battery system with external impingement cooling system

PRIOR ART In order to ensure the safety, function and service life of battery systems, in particular of lithium-ion battery systems, it is necessary to operate the cells within a predetermined temperature range. During power output, Joule's heat energy essentially arises, which can be described by the electrical current and the resistance of the cell. To avoid heating the cell beyond a critical temperature threshold, this heat energy must be dissipated effectively. In addition, the temperature distribution across the battery cell must be as homogeneous as possible, i. the temperature differences should not exceed 4 Kelvin.

One possibility for homogeneous temperature regulation is the removal of heat energy to a fluid flow, usually an air flow. Thus, for example, US Pat. No. 7,323,272 describes an arrangement which provides a flow around individual cells of a battery system with an air flow. A problem associated with such an arrangement is the high demands that must be placed on the air treatment, so that no disturbing, the life or function of the battery system affecting particles or liquids are spent in the battery system. Such drying and filtering steps consume additional energy and limit the cooling effect. Disclosure of the invention

The present invention provides a battery system with impingement cooling, comprising:

i) one or more battery cells;

ii) at least one housing in which the battery cells are arranged;

iii) a cooling plate located outside the housing; and iv) one or more passive heat conducting means arranged in such a way that thermal energy can be transmitted from the battery cells out of the housing interior to the cooling plate via the passive heat conducting means, characterized in that

the battery system has an impingement cooling for the convective transfer of heat energy from the cooling plate to a fluid flow, wherein the impingement cooling is configured such that a fluid flow for receiving heat energy is substantially perpendicular to a surface of the cooling plate feasible.

The heat energy produced in the cells is first conducted conductively via passive heat conducting means, such as cooling plates which are contacted with one or more lateral surfaces of the cells, to a cooling plate outside the housing. From there, the heat energy is transferred convectively to a fluid flow by means of impingement cooling with which locally very high heat transfer coefficients can be achieved. Under impingement cooling is understood to mean a cooling device, which is characterized in that a fluid flow for receiving heat energy substantially perpendicular to a heat-emitting surface and there generates a so-called "wall-jet", ie, the fluid flow is from the impact location in the radial direction on the Very high heat transfer rates can be achieved around the center of the impact location, which decrease with increasing radial distance from the center of the impact The battery system according to the invention with impingement cooling allows an efficient temperature regulation of the cells of the battery system by means of a fluid flow, while a fluid flow within of the housing is not necessary and thus measures for the treatment of the fluid are no longer necessary.

The battery system according to the invention comprises one or more battery cells. The term "battery system" here refers to electrochemical energy Memory understood, in particular batteries or accumulators of all conventional accumulator technologies. It can be batteries or rechargeable batteries of type Pb - lead acid battery, NiCd - nickel-cadmium rechargeable battery, NiH2 - nickel-hydrogen rechargeable battery, NiMH - nickel-metal hydride rechargeable battery, Li-Ion - lithium-ion battery 5, LiPo - lithium battery Polymer Battery, LiFe - Lithium Metal Battery, Li-Mn - Lithium

Manganese Battery, LiFeP0 ₄ - Lithium Iron Phosphate Battery, LiTi - Lithium Titanate Battery, RAM - Rechargeable Alkaline Manganese, Ni-Fe - Nickel-Iron Battery, Na / NiCI - High Temperature Nickel Nickel Chloride Battery, SCiB - Super charge ion battery, silver-zinc battery, silicone battery, vanadium redox-10 accumulator and / or zinc-bromine battery can be used. In particular, you can

Batteries of the type of lead / acid, nickel-cadmium, nickel-metal hydride and / or sodium / sodium nickel chloride battery can be used. Particular preference is given to using batteries of the lithium ion battery type. The term "battery system" is used both for individual cells, as well as for module s le of multiple cells, as well as for more complex architectures comprising multiple cells and / or modules.

The battery system includes one or more battery cells disposed in a common housing. In this case, a battery system can be a

20 ges or more individual housing, each one or more

Battery cells include. Preferably, the battery system has a common housing, in which all cells or modules of the battery system are arranged, wherein the cooling plate is positioned outside of this common housing. The term "housing" is to be understood as an apparatus

25 having an interior adapted to receive one or more battery cells. A housing may be permanently or temporarily open to the environment in one or two directions. Preferably, the housing delimits the contained battery cells from the environment in all directions, the housing providing closable accesses, e.g. doors

30 or cover may have. Under a housing can not be the immediate one

Cell cladding, which separates the electrochemical components of a single cell from the environment. Preferably, the housing can be made of a material which comprises or consists of a metal, a metal sheet or a ceramic. Particularly preferably, the housing of a

35 be made of material which comprises aluminum or consists thereof. The battery system according to the invention has at least one cooling plate, which is arranged outside the housing. The battery system may have a plurality of cooling plates arranged outside the housing. One, several or all of the cooling plates of the battery system may be externally attached to a surface of the housing. Preferably, one, several or all of the cooling plates of the battery system are mounted on an outside of the housing bottom. The cooling plates can be an integral part of the housing, provided at least one surface of the cooling plates is directly accessible from outside the housing for the supply of a fluid stream. Preferably, the cooling plate on a solid throughout configured surface, which does not allow direct passage into the housing interior. The cooling plates of the battery system are made of a material that has a heat transfer coefficient that allows the fastest possible and effective transfer of heat energy from the cooling plate to the fluid used. Corresponding materials are known to the person skilled in the art. The cooling plates preferably comprise or consist of aluminum.

The battery system according to the invention has one or more passive heat conducting means, which are arranged in such a way that thermal energy can be conductively transferred from the battery cells to the cooling plate via the passive heat conducting means. For this purpose, the passive heat conduction can be as large as possible in contact with one or more surfaces of the lateral surface of the battery cells, so that the fastest possible and effective heat transfer from the battery cells to the heat conducting is possible. The passive heat conducting means are designed such that an effective heat transfer is ensured both between the cell and the heat conducting means and between the heat conducting means and the cooling plate. The passive heat conduction of the battery system are made of a material having a heat transfer coefficient, which allow the fastest possible and effective transfer of heat energy from the battery cell to the heat conducting and the heat transfer to the cooling plate used. Corresponding materials are known to the person skilled in the art. The passive heat-conducting means are preferably conventional heat-conducting sheets, particularly preferably heat-conducting sheets which contain or consist of aluminum. The battery system according to the invention has an impingement cooling for the convective transfer of heat energy from the cooling plate to a flowing fluid, wherein the impingement cooling is configured such that a fluid flow for receiving heat energy can be guided substantially perpendicularly to a surface of the cooling plate. For this, the impingement cooling may comprise a distributor plate having at least one inlet for receiving a fluid flow and having on the side facing the cooling plate a plurality of outlets / nozzles, wherein the distributor plate is configured and arranged such that a fluid flow through the inlet into the Distributor plate is introduced and emerges from the distributor plate through the plurality of outlets such that the

Fluid flow substantially perpendicular to a surface of the cooling plate meets. In order to allow a uniform cooling capacity over the surface of the cooling plate, it makes sense to distribute the outlets evenly over the cooling plate facing surface of the distributor plate. The design of the outlets can be carried out arbitrarily, provided it is ensured that the outlets are suitable for letting the fluid used escape from the distributor plate. By way of example, the outlets may be round, oval, triangular, quadrangular, polygonal, square and / or slit-shaped, with the outlets of a distributor plate being designed to be uniform or different. The outlet geometry and arrangement on the distributor plate (e.g., outlet density per

Manifold plate area, sizing of the exhaust ports) may be varied as needed to provide suitable cooling for any desired battery type or battery capacity. The person skilled in the art can determine, without undue effort, by routine experiments alone, suitable parameters for the outlet geometry and arrangement for a given, given battery system. The distributor plate may be mounted so that it is directly and directly connected to the cooling plate. Alternatively, other devices may be provided which are positioned between the distributor plate and the cooling plate.

The impingement cooling of the battery system according to the invention can have a fluid distribution system which is designed in such a way that a fluid flow having a predetermined flow rate can be generated at the respective outlets of the distributor plate. The advantage of such a Fluidverteil- system is that so that at the respective outlets the desired amount of

Provided fluid per unit time and a corresponding fluid flow upright can be kept. Preferably, the fluid distribution system is designed such that at a plurality and / or all outlets of the distributor plate, a fluid flow at substantially the same flow rate can be generated. This ensures that the cooling capacity across the surface facing the cooling plate is uniform and homogeneous. Such a fluid distribution system may for example be formed as a separate device, which is positioned between the distributor plate and the cooling plate. However, such a fluid distribution system can also be an integral part of a distributor plate. For example, a fluid distribution system may have a plurality of fluid flow guides formed and arranged between the inlet and outlets of the distributor plate such that a fluid flow having substantially the same flow rate can be generated at a plurality and / or at all outlets of the distributor plate. The fluid flow guides for outlets that are relatively closer to the inlet, for example, may be made longer than fluid flow guides for outlets that are relatively further away from the inlet so that the fluid flow from the inlet of the distributor plate has to travel substantially the same distance through which Outlet the fluid flow exits. When carrying out such a fluid distribution system, the person skilled in the art may alternatively also orient himself to known so-called "rail" systems.

The fluid which is used as the fluid flow for cooling in the battery system according to the invention can in principle be any type of fluid which is suitable for absorbing heat energy from the cooling plate. This may be a liquid or gaseous fluid. Preferably, it is a gaseous fluid, in particular it may be air, for example ambient air of the battery system. To generate a fluid flow, it may be necessary to provide means which set the fluid below a predetermined, controllable and / or controllable pressure and supply the impingement cooling of the battery system according to the invention as pressure fluid flow. The fluid flow according to the invention is preferred as the fluid system according to the invention

Compressed air flow via the inlet or the inlets of the distributor plate (s) supplied.

The present invention also relates to motor vehicles comprising a battery system according to the invention. The term "motor vehicle" is to be understood as meaning all driven vehicles which have an electrochemical energy store, regardless of which drive they drive Have motor vehicles. In particular, the term "motor vehicle" includes HEV (electric hybrid vehicles), PHEV (plug-in hybrid vehicles), EV (electric vehicles), fuel cell vehicles, as well as all vehicles that use an electrochemical energy store for the electrical energy supply.

The present invention also relates to a method for cooling a battery system by means of impingement cooling, comprising the steps:

a) dissipation of heat energy of one, several or all cells, which are arranged in a housing of a battery system, to a cooling plate arranged outside the housing;

b) dissipation of heat energy from the cooling plate to a fluid by means of a guided outside the housing fluid flow, wherein the fluid flow is guided so that it meets substantially perpendicular to a surface of the cooling plate.

Characters:

FIG. 1 schematically shows the structure and operation of a

Impingement cooling.

FIG. 2 shows schematically the construction and the mode of operation of a battery system according to the invention.

In the following the invention will be clarified in more detail by means of exemplary embodiments.

In FIG. 1, the basic structure and operation of an impingement cooling system is shown schematically. A fluid flow 2 is guided such that it exits through an outlet 3 from a distributor plate 4 and substantially perpendicular to the body meets, with the temperature exchange is to be accomplished, in this case the cooling plate 1. Does the fluid stream 2 on the surface of the cooling plate. 1 , a so-called "wall-jet" is generated and the fluid flow is deflected in the radial direction and guided over the surface of the cooling plate 1. At around the center of the place of impact there is a transfer of heat energy with very high heat transfer rates.

In FIG. FIG. 2 schematically illustrates the structure and mode of operation of an embodiment of a battery system according to the invention. The battery system

10 includes a plurality of battery cells 1 1, preferably of lithium-ion cells, which may be combined in one or more modules and are arranged in a common housing 13. On the lateral surfaces of the battery cells 1 1 passive heat conducting 12, preferably 10 heat baffles, attached, conduct the heat energy of the battery cells 1 1 conductively along the direction of the closed arrow toward the cooling plate 14. The cooling plate 14 is formed here as a bottom plate, but may also be positioned at other positions outside the housing or on the outer surface of the housing, provided there is a heat-conducting Verl s bond between the passive heat conducting means 12 and the cooling plate 14. On the housing 13th opposite side of the cooling plate 14 is followed by a distributor plate 15, which is designed as impingement cooling. In the embodiment according to FIG. 2, the distributor plate 15 is directly and directly contacted with the housing 13 facing away from the surface of the cooling plate 20. 14. In FIG. 2, the distributor plate 15 is shown separated from the cooling plate 14 only to allow a schematic representation of the operation. The distributor plate 15 has an inlet 16 and a plurality of outlets 17, wherein the outlets 17 are positioned on the surface of the distributor plate 15 facing the cooling plate 14. In this case, the outlets 17 25 are preferably distributed uniformly over the surface of the distributor plate 15 facing the cooling plate 14 at regular intervals.

The resulting during operation of the battery system 10 in the battery cells 1 1 heat energy is first conductively transported via the passive heat conducting means 12 along the direction indicated by the closed arrow direction of the battery cells 1 1 30 toward the cooling plate 14 and thus led out of the housing 13. The cooling plate 14 absorbs the heat energy from the battery cells 1 1 and gives them to an impingement cooling. The impingement cooling is designed in the form of a distributor plate 15 and adjoins the cooling plate 14 directly on the side facing away from the housing 13. For cooling, a fluid flow into the distributor plate 15 can be introduced through the inlet 35 16, which then from the

Distributor plate exits through a plurality of outlets 17 such that the fluid flow is substantially perpendicular to a surface of the cooling plate 14 and receives there heat energy. The flow direction of the fluid flow is illustrated by the open arrows. The fact that the outlets 17 are distributed uniformly over the surface facing the cooling plate 14, a uniform cooling effect over a large part of the surface of the

Cooling plate 14 reached.

In the illustrated embodiment of the battery system according to the invention, the fluid flow guide takes place exclusively outside the housing 13 of the battery system 10 and does not enter the interior of the battery system 10, so that it is not necessary to work up the fluid used consuming before it can be used for cooling.

Claims

claims

1 . Battery system with impingement cooling, comprising

i) one or more battery cells;

ii) at least one housing in which the battery cells are arranged; iii) a cooling plate located outside the housing; and iv) one or more passive heat conducting means arranged in such a way that thermal energy can be transmitted from the battery cells out of the housing interior to the cooling plate via the passive heat conducting means, characterized in that

the battery system has impingement cooling for transmitting heat energy from the cooling plate to a fluid flow, wherein the impingement cooling is configured such that a fluid flow for receiving heat energy is substantially perpendicular to a surface of the cooling plate feasible.

2. Battery system according to claim 1,

characterized in that

the passive heat conducting means comprises one or more heat conducting sheets or consists thereof.

3. Battery system according to one of the preceding claims,

characterized in that

the impingement cooling comprises a distributor plate having at least one inlet for receiving a fluid flow and having a plurality of outlets on the side facing the cooling plate, the distributor plate configured and arranged such that fluid flow is introduced into the distributor plate via the inlet and emerges from the distributor plate through the plurality of outlets again such that the fluid flow strikes substantially perpendicular to a surface of the cooling plate.

4. Battery system according to claim 3,

characterized in that the outlets of the distributor plate are evenly distributed over the surface facing the cooling plate.

5. Battery system according to one of claims 3 or 4,

characterized in that

the impingement cooling system has a fluid distribution system which is embodied such that a fluid flow at a predetermined flow rate can be generated at the respective outlets of the distributor plate.

6. Battery system according to claim 5,

characterized in that

the fluid distribution system is designed such that at a plurality and / or all outlets of the distributor plate, a fluid flow with substantially the same flow rate can be generated.

7. Battery system according to claim 6,

characterized in that

the fluid distribution system has a plurality of fluid flow guides, which are designed and arranged such that a fluid flow with substantially the same is present at a plurality and / or all outlets of the distributor plate

Flow rate can be generated.

8. Battery system according to one of claims 3 to 7,

characterized in that

the distributor plate is connected directly to the cooling plate.

9. Motor vehicle comprising a battery system according to one of claims 1 to 8.

10. A method of cooling a battery system by means of impingement cooling, comprising the steps of:

b) discharging heat energy from the cooling plate to a fluid by means of a fluid flow conducted outside the housing, wherein the fluid flow of the is guided, that this meets substantially perpendicular to a surface of the cooling plate.