Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
  • H01M50/30—Arrangements for facilitating escape of gases
  • H01M50/342—Non-re-sealable arrangements
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
  • H01M50/30—Arrangements for facilitating escape of gases
  • H01M50/342—Non-re-sealable arrangements
  • H01M50/3425—Non-re-sealable arrangements in the form of rupturable membranes or weakened parts, e.g. pierced with the aid of a sharp member
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/05—Accumulators with non-aqueous electrolyte
  • H01M10/052—Li-accumulators
  • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
  • Y02E60/10—Energy storage using batteries

Definitions

• the present invention relates to an electrochemical cell and a battery arrangement with at least one such electrochemical cell.
• a flat-type lithium-ion battery is known, on whose housing frame a bursting area is provided.
• an overpressure protection is introduced in an opening.
• the overpressure safety device comprises a safety diaphragm, which breaks open in critical overpressure situations in order to allow the escape of gases.
• an electrochemical cell which has an electrode stack, which is sealed in a gas-tight and / or liquid-tight manner by an enclosure, and at least one pressure relief device, in particular in the form of a predetermined breaking point, wherein the at least one pressure relief device has a rupture disk which forms an opening the serving closes.
• an at least partial limitation is to be understood, which delimits the electrode stack (s) to the outside.
• the envelope is preferably gas and liquid tight, so that a material exchange with the environment can not take place.
• the electrode stacks are disposed within the enclosure.
• the envelope has at least one wrapping part, in particular a plurality of wrapping parts. Thus, for example, a wrapping part can be produced from a molded part.
• a frame or a frame part represent a wrapping part.
• At least one current conductor in particular two current conductors extend out of the enclosure and serve to connect the electrode stacks.
• the outwardly extending current conductors preferably represent the positive pole connection and the negative pole connection of the electrochemical cell.
• a plurality of current conductors it is also possible for a plurality of current conductors to extend out of the enclosure, in particular four current arresters. If the electrochemical cell has two electrode stacks which are connected in series with one another, two electrodes of different electrode stacks are connected to one another.
• an electrode stack is to be understood as meaning a device which, as an assembly of an electrochemical or galvanic cell, also serves to store chemical energy and to deliver electrical energy.
• the electrode stack has a plurality of plate-shaped elements, at least two electrodes (anode and cathode) and a separator which at least partially receives the electrolyte.
• at least one anode, a separator and a cathode are stacked or stacked, wherein the separator is at least partially disposed between the anode and the cathode.
• This sequence of anode, separator and cathode can be repeated as often as desired within the electrode stack.
• the plate-shaped elements are wound into an electrode winding.
• electrode stack will also be used for electrode windings. ⁇ br/> ⁇ br/> Prior to the release of electrical energy, stored chemical energy is converted into electrical energy Charging the electrical energy supplied to the electrode stack or the galvanic cell is converted into chemical energy and stored.
• the electrode stack has a plurality of electrode pairs and separators. Particularly preferably, some electrodes are in particular electrically connected to one another.
• a framework is to be understood to mean any constructional device which is suitable for mechanically stabilizing the cell against environmental influences, in particular against forces acting from the outside or inside, and which is firmly connected to the packaging of the cell during the production of the cell can be.
• a frame is preferably a substantially frame-shaped device, the function of which is essentially to impart mechanical stability to a galvanic cell.
• the frame can represent a cladding part.
• a pressure relief device is in particular a device of this type which, when a specific pressure, namely a bursting pressure, occurs, in particular allows material to escape from the interior of the electrochemical cell to the outside. Further, a pressure relief device may allow leakage of material from the electrochemical cell interior to the outside when a certain temperature, namely a bursting temperature is reached or exceeded.
• a pressure relief device can initiate a depressurization process independently of the pressure only when the bursting temperature occurs.
• a pressure relief process is particularly present when material from the electrochemical cell interior, in particular due to an opening of the pressure relief device can escape to the outside.
• the pressure relief device is designed in the form of a predetermined breaking point.
• a predetermined breaking point is designed in particular such that parts of the pressure relief device are destroyed in the case of a pressure relief process.
• the pressure relief device has a rupture disk which closes an opening of the casing.
• the rupture disc closes the breakthrough of the enclosure only in the case where a pressure relief process is not present.
• the closing of the breakthrough is disturbed by the rupture disk, so that the rupture disk can at least not completely prevent a passage of material through the opening. More detailed embodiments of the rupture disk and the corresponding Verschoudreungs- possibilities of breakthrough through the rupture disk are discussed in more detail below.
• the rupture disk may be made of a plastic, in particular of a polymer.
• the rupture disk can be designed in its geometric dimensions and / or mechanical properties such that it loses its mechanical strength when reaching the bursting pressure or the bursting temperature and thus can no longer seal the casing.
• the plastic for the production of the rupture disk can be represented by PE, PP, PTFE, CTFE, FEP, HFP or other in particular fluorinated polymers.
• the rupture disk is made of a film.
• the film can be at least partially destroyed when reaching or exceeding the bursting pressure, in particular tear.
• the film can melt even when reaching or exceeding the bursting temperature.
• the rupture disk and the enclosure are made of a substantially identical material. In this case, first the casing can be produced completely closed and then the rupture disk can be cut out of the casing, in particular cut out or punched out. The rupture disk can then be firmly closed again with the wrapper. As a result, the costs for the production of the envelope can be reduced together with the pressure relief device.
• the rupture disk preferably has a plurality of layers, including in particular a diffusion-reducing layer.
• a diffusion-reducing layer may preferably be based on fluoropolymers, silicone or paraffin.
• a layer of the rupture disk can be made of a metal, in particular of aluminum.
• a layer may be vapor-deposited on another layer of the rupture disk, in particular the aluminum layer may be vapor-deposited onto a plastic layer.
• Plastics based on hydrocarbons can in particular favor the diffusion of water or water vapor.
• the diffusion-reducing layer preferably prevents the diffusion of water or water vapor through the bursting disc. This can also be achieved by a metal layer.
• a metal layer of the cladding namely in particular a cladding part and / or the rupture disk, can be coated by means of a polymer coating. This can prevent possible corrosion of the metal layer. In particular, when the metal layer faces the interior of the electrochemical cell, this can prevent corrosion by the electrode stack and the materials located there.
• the metal layer can by targeted oxidation to form a dense oxide layer, in particular by anodizing, pretreated. This can result in a further resistance to corrosion.
• a metal layer can also be subjected to further pretreatments, which in particular have a corrosion-protecting effect. These are, in particular, application of a metal oxide layer, metal nitride layer or other protective layers, in particular by plasma processes, sputtering or electrolytic treatments.
• the pressure relief device upon reaching a bursting temperature, initiates a pressure relief operation.
• a layer of the rupture disk can be made of a material whose melting temperature is below the bursting temperature. It can thereby be achieved that the one layer whose melting temperature is below the bursting temperature melts and in particular loses the mechanical properties before the bursting temperature is reached. Due to the fact that this layer only has negligible mechanical properties when the bursting temperature is reached, the exact setting of the bursting point can only be set on the other layer.
• bursting point is meant that operating state in which a pressure relief process is initiated by the pressure relief device. The bursting point is determined in particular by the bursting temperature and / or the bursting pressure.
• the rupture disk is formed of a polymer layer and a paraffin layer, wherein the melting point of the paraffin layer is less than 85 ° C and in particular at about 80 ° C, and the polymer layer has a melting point, preferably above 95 ° C, in particular at about 100 ° C is located.
• the breakthrough can have a round shape.
• the round shape is easy to manufacture, especially by drilling.
• the breakthrough may also have a polygonal shape.
• the aperture has an elongate shape, ie, in a first cross-sectional direction, the aperture has an extension which is greater by a multiple, in particular at least twice, than the dimension in a second extension perpendicular thereto.
• the rupture disk is preferably made larger than the breakthrough. It can thereby be achieved that the rupture disk covers the breakthrough and in particular rests on a shoulder on the casing. As a result, an improved sealing effect can be achieved.
• the rupture disk is sealed or glued to the wrapper.
• the rupture disk can be materially connected to the enclosure.
• the type of Aufêteins or sticking can even set the bursting temperature or the bursting pressure. If the seal or bond dimensioned larger, the bursting pressure or the bursting temperature may increase. Conversely, if the seal or bond is reduced, the burst temperature or burst pressure can be reduced.
• the rupture disk is screwed into the opening.
• the breakthrough preferably has a thread which is mounted in the opening.
• the thread can be made by screwing the rupture disk itself.
• the rupture disk can have a particular self-tapping thread.
• the rupture disk is preferably provided with means which allow a transmission of torque to the rupture disk.
• screw heads are applicable. These can be in particular a hexagonal shape or an imbus shape.
• the bursting disc can also be held by means of a holding part at the opening.
• the holding part may in particular be formed separately.
• the holding part can be firmly and / or non-positively and / or positively attached to a part of the enclosure.
• the holding part can rupture the rupture disk firmly and / or positively and / or positively hold on breakthrough.
• the holding part can be screwed onto a thread in the opening.
• the bursting foil can be arranged between the holding part and a shoulder in the opening. By screwing the holding part in the direction of the paragraph, the bursting film between the holding part and paragraph is clamped and thus held.
• the retaining member may be threaded onto a thread within the aperture. The film is applied to the thread in the opening and is screwed when screwing the holding part between the threads of the holding part and the opening.
• the rupture disk has a base area that is larger than a cross section of the opening.
• a separate sealing means is preferably provided between rupture disk and sheath.
• This may in particular be a polymer seal.
• the sealing agent may preferably be formed in disk form or in ring form.
• the electrochemical cell preferably has a cutting means, in particular a mandrel or a blade, which can damage parts of the envelope, in particular the rupture disk.
• the cutting means may break through portions of the enclosure.
• the mechanical stability of the casing in particular in the area of the pressure relief device, can be reduced, which can have an effect on the bursting pressure or the bursting temperature.
• a depressurization process is initiated because material may leak from the interior of the electrochemical cell to the outside at the broken point of the casing.
• the cutting means can be placed on the opening from the outside. In this case, the separating agent protrude into the breakthrough.
• the cutting means can be attached to a plate or on a disc which is placed from the outside on the breakthrough.
• the plate or disc may be gas and / or liquid permeable.
• the cutting means is arranged outside the rupture disk and aligned with the rupture disk.
• Arranged outside, in particular, means that the cutting means is arranged on one side of the sheathing or rupture disk, which faces away from the interior of the electrochemical cell.
• the rupture disk is arranged in particular between the interior of the electrochemical cell and the cutting means.
• the electrochemical cell has sensor means that can detect a pressure relief process.
• a sensor means that can detect a pressure relief process.
• a central control unit can be informed that the electrochemical cell is in a state in which it no longer functions properly.
• the electrochemical cell can then be decoupled from other uses, in particular charging or discharging.
• Such sensor means may be formed as temperature sensors and / or pressure sensors.
• a required pressure relief process can be detected in particular by determining by means of a pressure or temperature sensor an initially increasing pressure or an initially rising temperature. For this purpose, the gradient of the pressure or temperature change can be used.
• the at least one pressure relief device is arranged in a region remote from a current conductor of the electrochemical cell.
• the at least one pressure relief device is arranged in the installed state of the electrochemical cell in the lower and / or lateral region of the electrochemical cell.
• the at least one current conductor of the electrochemical cell extends out of the first area of the enclosure and the at least one pressure relief device is arranged in a second area of the enclosure facing away from the first area and / or is at least one Pressure Relief device in the installed state of the electrochemical cell arranged in a lower portion of the enclosure.
• the at least one pressure relief device as far as possible (far) away from the current conductors and / or arranged in the lower region of the cell.
• the advantages are achieved in this context that at an increased internal cell pressure, the pressure reduction and the material discharge by the at least one pressure relief device neither in the area of the current arrester and the battery management system nor in the direction of the passenger compartment.
• the invention further relates to a battery arrangement, comprising at least one, in particular a plurality of electrochemical cells of the type mentioned above.
• FIG. 1 A first figure.
• FIG. 3 shows a section of the enclosure of an electrochemical cell 1 in an alternative embodiment
• Fig. 5 different cross-sectional shapes of the apertures
• FIG. 1 shows an electrochemical cell 1 according to the invention.
• the envelope 2 surrounds an interior 14 of the electrochemical cell 1 in a gas-tight and liquid-tight manner with respect to the surroundings.
• an electrode stack 13 is arranged in the interior 14 of the electrochemical cell 1.
• electrochemical cells can be arranged in a battery (arrangement).
• FIG. 2 shows a section of the envelope 2.
• the envelope 2 is designed in several parts.
• the casing 2 has at least one wrapping part 3.
• the wrapping part 3 is designed as a molded part.
• the envelope 2 has two such molded parts 3.
• a wrapping part can also have a different shape.
• a frame may also represent a wrapping part 3.
• the two mold parts 3 make up the largest part of the casing 2.
• the wrapping part 3 has an opening 6, which is closed by a rupture disk 5.
• the rupture disk 5 forms, together with the wrapping parts 3, the wrapping 2.
• the rupture disk 5 is adhered to the enclosure 3.
• the rupture disk 5 can be sealed onto the wrapping part 3.
• the opening 6 is formed in stages and has an outer portion 15 and an inner portion 16.
• the outer portion 15 has a smaller diameter than the inner portion 16.
• a shoulder 17 is formed on which rupture disc 5 rests.
• the rupture disk 5 is placed on the shoulder 17 from the inside.
• the rupture disk 5 is glued on the shoulder 17.
• the rupture disk 5 is made of a single-layer plastic film.
• FIG. 3 shows a section of the envelope of an electrochemical cell 1 in an alternative embodiment, which largely corresponds to the envelope according to FIG. In this respect, only the differences from FIG. 2 will be discussed below.
• the rupture disk 5 is designed as a multi-layer bursting foil.
• the rupture disk 5 has a first layer 7 and a second layer 8.
• the first layer 7 is made of a polymer.
• the second layer 8 is made of aluminum.
• the aluminum layer 8 has over the polymer layer on an improved water vapor impermeability and is insofar formed diffusion-reducing.
• the aluminum layer 8 has an improved tear strength.
• the wrapping part 3, which is a molded article is also constructed of a multilayer material, wherein an outer layer of aluminum and an inner layer of a polymer are made. The two layers of the bursting foil 5 as well as the two layers of the molded part 3 can be reversed.
• the layer of aluminum may also be replaced by a layer based on a fluoropolymer, silicone or paraffin.
• the second layer 8, which represents the inner layer of the bursting foil 5 may be made of a paraffin-based material.
• the paraffin-based material melts at about 80 ° C. However, only at 100 ° C is the bursting temperature. In this respect, the second layer is melted away before reaching the bursting temperature and therefore without mechanical strength.
• This has the advantage that for sizing the Pressure relief device 4 only the first layer 7 can be used.
• the second layer 8 does not change the bursting properties of the pressure relief device 4, in particular with regard to the bursting temperature.
• the bursting film 5 is placed on the paragraph 17.
• the bursting film 5 is not glued directly to the shoulder 17 or otherwise materially connected. It is provided an annular holding part 9, which is placed on the bursting film 5 from the inside.
• the holding part 9 is firmly held in the opening 6, in particular in the second portion 16 of the opening 6.
• the holding part 9 can be used with oversize in the wrapping part 3.
• the holding member 9 can be firmly bonded in the opening 6, in particular by means of gluing.
• the holding part 9 may have an external thread, which is screwed into an internal thread of the opening 6.
• the rupture disk can in particular be designed as a bursting foil and screwed in between the internal thread of the opening 6 and the external thread of the holding part 9.
• FIG. 4 shows a detail of the envelope of an electrochemical cell 1 in a further alternative embodiment, which largely corresponds to the envelope according to FIG. In this respect, only the differences from FIG. 3 will be discussed below, and single-layer bursting films according to FIG. 1 may also be used. Between bursting film 5 and the paragraph 17, a separate sealing washer 10 is provided, which improves the sealing effect in normal operation.
• a disc 18 is placed from the outside, which has a centrally disposed mandrel 11 on an inner surface.
• the mandrel 11 is aligned with the rupture disk 5.
• the bursting foil 5 expands in the direction of the dome 11.
• the disc 18, which carries the mandrel is not sealingly connected to the enclosure 2.
• the disc 18 may have apertures that allow passage of material through the disc 18 therethrough.
• FIG. 5 shows various cross-sectional shapes which the apertures 6 can have.
• Figure 5a) shows an oval shape.
• FIG. 5b) shows a circular shape.
• FIG. 5c) shows a rectangular shape in which the corners are rounded off.
• Figure 5d) shows a regular polygon, namely a hexagon, wherein the internal angles of the regular polygon are all identical to each other. Only two opposite sides of the regular polygon are formed extended compared to the other sides.
• FIG. 5 e) shows the shape of a regular octagon.
• Figure 5f) is similar to the cross-section as shown in Figure 5c). However, the ratio of the large side lengths to the small side lengths is greater than in the cross section of Figure 5c).
• FIG. 6 a shows the pressure curve in the interior 14 of the electrochemical cell 1.
• the pressure relief device 4 is closed so that there is no pressure relief process. There can be no material from the interior 14 through the enclosure 2 to the outside.
• the pressure P in the interior 14 increases.
• the pressure P reaches the bursting pressure PB.
• the pressure relief device opens and material can pass from the interior 14 to the outside.
• the pressure P in the interior 14 can be reduced, so that subsequently in the time t> t B, the pressure P decreases again.
• FIG. 6 b shows the temperature profile in the interior 14 of the electrochemical cell 1.
• the pressure relief device is closed.
• the temperature T in the interior 14 increases.
• the temperature T reaches the bursting temperature T B.
• the pressure in the interior 14 can be reduced, as a result of which the temperature in the interior can also be reduced.
• a pressure relief process can be detected by means of a sensor 12, which is arranged in the interior of the electrochemical cell.
• a central control unit which is connected to the sensor means 12, subsequently switches off the electrochemical cell from further charging and discharging operations.
• the at least one pressure relief device 4 is preferably provided in an area facing away from the current conductors of the electrochemical cell at the bottom or side of the enclosure 2 or the cell 1, so that the at least one pressure relief device 4 as far as possible ) is removed from the current conductors and arranged in the lower and / or lateral region of the cell 1.

Landscapes

• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Electrochemistry (AREA)
• General Chemical & Material Sciences (AREA)
• Gas Exhaust Devices For Batteries (AREA)
• Sealing Battery Cases Or Jackets (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=42985544

Family Applications (1)

Country Status (8)

Families Citing this family (21)

Citations (2)

Family Cites Families (18)

• 2009
  • 2009-10-05 DE DE102009048236A patent/DE102009048236A1/de not_active Withdrawn
• 2010
  • 2010-08-17 KR KR1020127011385A patent/KR20120093253A/ko not_active Application Discontinuation
  • 2010-08-17 US US13/500,350 patent/US20120282499A1/en not_active Abandoned
  • 2010-08-17 JP JP2012532472A patent/JP2013506966A/ja active Pending
  • 2010-08-17 EP EP10751803A patent/EP2486612A1/de not_active Withdrawn
  • 2010-08-17 CN CN201080044734XA patent/CN102687307A/zh active Pending
  • 2010-08-17 WO PCT/EP2010/005043 patent/WO2011042092A1/de active Application Filing
  • 2010-08-17 BR BR112012007807A patent/BR112012007807A2/pt not_active IP Right Cessation

Patent Citations (2)

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events