Cylindrical battery cell and associated production method

Abstract

The invention relates to a method for producing a cylindrical battery cell. The method comprises the following steps: a) providing (100) a cylindrical battery cell blank (11) having an outer wall which comprises steel; b) applying (300) a primer (19) to at least parts of the outer wall; c) closing (400) the battery cell blank (11) by laser welding or by means of a crimping closure; and d) filling (500) the battery cell blank (11) with an electrolyte (18). The invention further relates to a cylindrical battery cell (10), to a battery pack (20) comprising a plurality of cylindrical battery cells (10), to a method for producing the battery pack and to a motor vehicle (30) comprising at least one battery pack (20).

Description

Cylindrical battery cell and method for producing the same The present invention relates to a method for producing a cylindrical battery cell, a cylindrical battery cell, a battery pack comprising a plurality of cylindrical battery cells and a method for producing the same, as well as a motor vehicle comprising at least one battery pack. Cylindrical battery cell casings are typically made of nickel-plated steel due to a combination of factors, including durability, safety, and conductivity. When it comes to safety, nickel-plated steel is preferred for battery cell casings due to its strength and resistance to deformation. Cylindrical batteries can generate a lot of pressure and heat, especially during charging or discharging, which can cause the battery to expand or rupture if the casing isn't strong enough to contain the internal pressure. This is the primary reason for using silicon anodes. Steel is a strong and rigid material that can withstand high pressures without deforming, making it ideal for use in battery cell casings. In addition, steel has a high melting point, which means it can withstand high temperatures and prevents the battery from exploding in the event of a short circuit. or other malfunction catches fire or explodes. In addition, steel is a relatively inexpensive material, which helps keep battery manufacturing costs low. Furthermore, steel is a readily available material and can easily be formed into the cylindrical shape required for the battery casing. Nickel plating provides additional protection against corrosion and improves the electrical conductivity of the casing, allowing energy to be transferred efficiently into and out of the battery. However, the integrity of the battery is compromised during battery cell manufacturing. This occurs primarily during the transport of individual battery cells and cell integration into a battery pack. It would therefore be desirable to provide cylindrical battery cells and methods for producing them which, by simple means, improve the corrosion resistance and thus also the integrity of the battery. The aim of the invention is to propose a possibility which avoids or at least reduces at least some of the disadvantages known in the prior art. The object is achieved according to the invention by means of a method for producing a cylindrical battery cell according to the main claim, as well as by means of a cylindrical battery cell, a battery pack and a Process for producing the same, and a Motor vehicle according to independent claims . The subject matter of the main claim relates to a method for producing a cylindrical battery cell. The method comprises a step a) of providing a cylindrical battery cell blank with an outer wall. The outer wall of the cylindrical battery cell blank comprises steel. The method further comprises a step b) of applying a primer to at least parts of the outer wall of the cylindrical battery cell blank. The method further comprises a step c) of closing the battery cell blank. The closing is carried out by means of laser welding or crimping. The method further comprises a step d) of filling the battery cell blank with an electrolyte. The process steps can be carried out automatically. Step a) of providing a cylindrical battery cell blank comprising steel is known to those skilled in the art. For example, a cylindrical battery cell blank can be provided by the steps of producing the battery cell blank, coating, drying, compacting, cutting, singulating, and coiling. The application of the primer b ) can be carried out on at least parts of the outer wall or on the entire outer wall of the Battery cell blank. The primer can preferably be applied to parts of the outer wall. The primer is preferably applied to those parts of the outer wall that are most susceptible to damage during subsequent sealing of the battery cell blank. Damage occurs primarily through impairment of the coating, such as the nickel coating, which can lead to corrosion of the battery cell casing. These parts of the outer wall are known to the expert. For example, when sealing the battery cell blank with a crimp closure, certain areas of the outer wall of the can are severely deformed by the deep drawing process. Furthermore, severe deformation can occur due to beads / grooves in the area of the crimp seal. Furthermore, the nickel-plated layer can also be severely deformed in the area of the crimp closure and in the area of the edge notch during can production. When closing the battery cell blank using laser welding, damage may occur in the area of the laser weld seam, which has no nickel coating, as well as at the laser contact surface on the cap / jelly roll. A primer application can prevent corrosion of a steel surface by forming a protective barrier between the steel and the environment. When steel is exposed to moisture, oxygen, and other corrosive elements, it can begin to rust and corrode over time. However, if a primer is applied to the steel surface, it can act as a barrier to prevent these elements from coming into contact with the steel. Primers typically contain a variety of chemicals and compounds designed to protect the steel surface from corrosion. These chemicals include zinc, chromates and other corrosion inhibitors that can prevent the formation of rust on the surface. In addition, primers can also help create a smooth and even surface for subsequent paint or other protective coatings. When properly applied, a primer can form a durable and long-lasting protective layer on the steel surface, preventing corrosion and extending the service life of the steel. However, it's important to note that a primer alone is not sufficient to prevent corrosion in all cases. In some cases, additional protective coatings or maintenance are required to fully protect the steel surface from the elements. The primer application according to the invention is easier than the application of a conventional full coating, which requires cleaning, priming and coating. Current technology involves washing battery cells in a water bath to remove electrolyte residue. This is costly. In the present invention, electrolyte residues adhering to the outer wall are prevented by the applied primer. This may make it possible to reduce the complexity or even eliminate an additional process step for washing the battery cell blank or battery cell. This can reduce production costs. In a more preferred embodiment, the primer can be applied at least on the closure side of the battery cell blank. The various ways of applying the primer to at least parts of the outer wall of a cylindrical battery cell blank are known to the person skilled in the art. The application can be carried out by methods known to the person skilled in the art, such as pneumatic application, a spraying process, dip wetting or a plasma nozzle process. -1- A primer in the sense of the invention is a Adhesion promoter. All known primers can be used. Primers are familiar to those skilled in the art. When using a stabilizing agent, such as a foam, the primer can be matched to the corresponding stabilizing agent. In a preferred embodiment, the primer comprises silane-based adhesion promoters as the primary group. Silane-based adhesion promoters are known to those skilled in the art. For example, the silane-based adhesion promoter may comprise silane-based adhesion promoters. For example, the silane-based coupling agent may comprise N-2-aminoethyl-3-aminopropyltrimethoxysilane. The battery cell can be sealed by laser welding or crimping using appropriate methods known to those skilled in the art. Filling the battery cell with an electrolyte is known to those skilled in the art. For example, the electrolyte is introduced into the battery cell blank under pressure. The method may further comprise a step e) of applying a corrosion protection agent. Step e) may be carried out before step b) of applying a primer to at least parts of the outer wall. The application of corrosion protection is known to the expert. All known corrosion inhibitors that can prevent the formation of rust on a surface such as steel can be used for corrosion protection. Corrosion inhibitors that can prevent the formation of rust on a surface such as steel are known to those skilled in the art. In a preferred embodiment, the corrosion protection may comprise at least one selected from the group consisting of nickel, zinc, chromates. In a particularly preferred embodiment, the corrosion protection may comprise nickel. After filling the battery cell blank with an electrolyte and closing the part of the battery cell blank through which the electrolyte is filled, the cylindrical battery cell can be formed. The subject matter of a subordinate claim relates to a cylindrical battery cell comprising a positive electrode, a negative electrode, a separator, an electrolyte and a primer located at least on parts of the outer wall of the cylindrical battery cell. In a preferred embodiment, the cylindrical battery cell is provided with the inventive Process for producing a cylindrical battery cell. A positive electrode within the meaning of the invention is a cathode. Cathode materials are known to those skilled in the art. The cathode may comprise LCO (lithium cobalt oxide), LMS or LMO (lithium manganese oxide spinel), NMC or NCM (lithium nickel cobalt manganese), LED (lithium iron phosphate), NCA (lithium nickel cobalt aluminum oxide) or NCMA (nickel cobalt manganese aluminum). A negative electrode within the meaning of the invention is an anode. Anode materials are known to those skilled in the art. The anode may comprise natural graphite, synthetic graphite, spherical graphite, silicon, silicon compounds and mixtures thereof. Separator materials are known to those skilled in the art. The separator can comprise plastic or ceramic polymers. Electrolyte materials are known to those skilled in the art. The electrolyte salts such as lithium hexafluorophosphate (LiPFe), lithium tetrafluoroborate (LiBF4) or lithium bis(oxalato)borate (LiBOB) dissolved in anhydrous aprotic solvents such as ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate or 1,2-dimethoxyethane, polymers of polyvinylidene fluoride (PVDF) or polyvinylidene fluoride-hexafluoropropene (PVDF-HEP), lithium phosphate nitride (LisPChN), lithium titanium thiophosphate (LiTi2(PS4)3) or LISICON (Li2+2xZn- x GeO4). The subject matter of a further independent claim relates to a method for producing a battery pack. The method for producing a battery pack comprises a step of arranging a plurality of cylindrical battery cells such that they are spaced apart from one another. The method further comprises a step of electrically connecting the battery cells to one another such that the battery pack acts as a single battery. The method further comprises a step of introducing a stabilising agent between the spaced-apart battery cells such that the stabilising agent can withstand a compressive force of up to 500 N Newtons acting on the battery pack from the outside. The arrangement of a plurality of cylindrical battery cells such that they are arranged at a distance from one another is known to the person skilled in the art. The electrically conductive connection of the battery cells to one another in such a way that the battery pack acts as a single battery is known to those skilled in the art. The introduction of a stabilizing agent between the spaced-apart battery cells is carried out according to methods known to those skilled in the art, as long as the stabilizing agent covers almost all surfaces affected by damage to the outer wall, which comprises steel or which has corrosion protection. The external compressive force acting on the battery pack can be measured using methods known to those skilled in the art. For example, the external compressive force acting on the battery pack can be measured according to the DIN 1456 standard for plastic-metal connections. The stabilizing agent can withstand a compressive force acting on the battery pack from the outside of up to 500 Newton, up to 600 Newton, up to 700 Newton, up to 800 Newton, up to 900 Newton, up to 1000 Newton, up to 1100 Newton, up to 1200 Newton, up to 1300 Newton, up to 1400 Newton, up to 1500 Newton, up to 1600 Newton, up to 1700 Newton, up to 1800 Newton, up to 1900 Newton, up to 2000 Newton, up to 2100 Newton, up to 2200 Newton, up to 2300 Newton, up to 2400 Newton, up to 2500 Newton, up to 2600 Newton, up to 2700 Newton, up to 2800 Newton, up to 2900 Newton, up to 3000 Newton, up to 3100 Newton, up to 3200 Newton, up to 3300 Newton, up to 3400 Newton, up to 3500 Newton, up to 3600 Newton, up to 3700 Newton, up to 3800 Newton, up to 3900 Newton, up to 4000 Newton, up to 4100 Newton, up to 4200 Newton, up to 4300 Newton, up to 4500 Newton, up to 4600 Newton, up to 4700 Newton, up to 4800 Newton, up to 4900 Newton and up to 5000 Newton. In a preferred embodiment, the stabilizing means can withstand a compressive force of up to 1000 Newtons acting externally on the battery pack. In a more preferred embodiment, the Stabilizing agent withstands an external pressure force of up to 5000 Newtons acting on the battery pack. The stabilizing agent provides structural support for the energy module, i.e. the battery pack. Furthermore, the stabilizing agent is chemically bonded to the primer, preventing corrosion caused, for example, by moisture intrusion into the boundary layer between primer / battery cell / foam. All known stabilizing agents can be used as stabilizing agents that promote the structural load-bearing capacity of the energy module and allow chemical bonding of the stabilizing agent to the primer. This means that the stabilizing agent is coordinated with the primer or adhesion promoter. Such stabilizing agents are known to the person skilled in the art. In a preferred embodiment, the stabilizing agent comprises a foam. All known foams can be used that are conducive to the structural load-bearing capacity of the energy module and allow chemical bonding of the foam to the primer. In a more preferred embodiment, the foam is a polyurethane foam. Polyurethane foams are known to those skilled in the art. A polyurethane foam which can be used in the present invention is a polyurethane foam which can be prepared by a polyaddition reaction of a polyol, such as a polyether polyol or a polyester-based polyol, with a polyisocyanate, such as tolylene diisocyanate (TDI) or diphenylmethane diisocyanate (MDI). Furthermore, the polyurethane foam used in the present invention may contain additives known to those skilled in the art. Additives contained in the polyurethane foam of the present invention may include blowing agents, activators and / or foam stabilizers. Propellants can include, for example, chlorofluorocarbons (CFCs) / chlorofluoroalkanes (Frigene) substitutes (including hydrocarbons) and water. Activators may include triethylamine, organic tin compounds such as dibutyltin dilaurate and stannous dioctate, and emulsifiers such as silicone oils. Foam stabilizers may include polymethylsiloxane-polyalkylene oxide block polymer. The cylindrical battery cell can be used in a The present invention also relates to a battery pack comprising a plurality of cylindrical battery cells according to the invention. In a preferred embodiment, the battery pack is manufactured using the method according to the invention for manufacturing a battery pack. A plurality in the sense of the present invention means at least two. A plurality can also mean three, four, five, six, or more. The battery pack can be used in a vehicle. The present invention also relates to a vehicle having the battery pack comprising at least a plurality of battery cells according to the invention. The battery pack can function as a battery pack for providing electrical energy for an electric motor of the motor vehicle. The motor vehicle can thus be operated by means of the battery pack according to the invention. This means that the motor vehicle can use the battery pack according to the invention to provide electrical energy for the motor vehicle. Therefore, the battery pack according to the invention can supply electrical components of the motor vehicle with electrical energy. Thus, for example, the on-board system of the motor vehicle and / or other motor vehicle components and motor vehicle systems can be supplied with electrical energy by the battery pack according to the invention. In particular, the motor vehicle can The battery pack according to the invention can be powered at least partially electrically. The motor vehicle can also be powered fully electrically using the battery pack according to the invention. Special designs [1] A method for producing a cylindrical battery cell (10), the method comprising the following steps: a) providing (100) a cylindrical battery cell blank (11) with an outer wall which comprises steel; b) applying (300) a primer (19) to at least parts of the outer wall; c) closing (400) the battery cell blank (11) by means of laser welding or crimping; d) filling (500) the battery cell blank (11) with an electrolyte (18). [2] The method according to paragraph [1] further comprising a step e) of applying (200) a corrosion protection preferably comprising at least one selected from the group consisting of nickel, zinc, chromates, preferably nickel, wherein step e) takes place before step b). [3] The method according to any one of the preceding paragraphs, wherein the primer (19) is applied at least on the closure side of the battery cell blank (11). [4] The method according to any one of the preceding paragraphs, wherein the primer (19) comprises at least one silane-based coupling agent, for example N-2-aminoethyl-3-aminopropyltrimethoxysilane. [5] The method for producing a battery pack (20) comprising: Arranging (1000) a plurality of cylindrical battery cells (10) such that they are arranged at a distance from one another; Electrically connecting (2000) the battery cells (10) to one another such that the battery pack (20) acts as a single battery; Introducing (3000) a stabilizing agent between the spaced-apart battery cells (10) such that the stabilizing agent withstands a compressive force of up to 500 N Newton, preferably up to 1000 Newton and more preferably up to 5000 Newton acting externally on the battery pack (20). [6] The process according to paragraph [5] , wherein the stabilising agent comprises a foam. [7] The process according to paragraph [6] , wherein the foam is a polyurethane foam. [8] A cylindrical battery cell (10) comprising: a positive electrode (12); a negative electrode (14); a separator (16); an electrolyte (18); and a primer (19) located at least on parts of the outer wall of the cylindrical battery cell (10). [9] A battery pack (20) comprising a plurality of cylindrical battery cells (10) according to paragraph [8] .

[0010] A motor vehicle (30) comprising at least one battery pack (20) according to paragraph [9] . The invention will be explained in more detail below with reference to the figures, in which: Fig. 1: a schematic view of an embodiment of the method for producing a cylindrical battery cell; Fig. 2: a schematic view of another embodiment of the method for producing a cylindrical battery cell; Fig. 3: a schematic view of an embodiment of the method for producing a battery pack; Fig. 4 is a schematic representation of a proposed device according to a further exemplary embodiment of the invention; Fig. 5 is a schematic representation of a proposed device according to a further exemplary embodiment of the invention; and Fig. 6 is a schematic representation of a proposed device according to a further exemplary embodiment of the invention. Fig. 1 shows a schematic view of a Embodiment of the method for producing a cylindrical battery cell. Fig. 1 shows a schematic representation of a method for producing a cylindrical battery. The method comprises: providing 100 a cylindrical battery cell blank 11 with an outer wall which has steel. The method also comprises applying 300 a primer 19 to at least parts of the outer wall. The method also comprises closing 400 the battery cell blank 11 by means of laser welding or crimping. Furthermore, the method comprises 500 filling the battery cell blank 11 with an electrolyte 18. Fig. 2 shows a schematic view of another embodiment of the method for producing a cylindrical battery cell. Fig. 2 shows a schematic representation of the process for producing a cylindrical battery. The method comprises: providing 100 a cylindrical battery cell blank 11 with an outer wall which comprises steel. Furthermore, the method comprises applying 200 a corrosion protection prior to the application 300. The corrosion protection preferably comprises at least one selected from the group consisting of nickel, zinc, chromates, preferably nickel. Furthermore, the method comprises applying 300 a primer 19 to at least parts of the outer wall. Furthermore, the method comprises closing 400 the battery cell blank 11 by means of laser welding or crimping. Furthermore, the method 500 comprises filling the battery cell blank 111 with an electrolyte 18. Fig. 3 shows a schematic view of an embodiment of the method for producing a battery pack. Fig. 3 shows a method for producing a battery pack. The method comprises arranging 1000 a plurality of cylindrical battery cells 10 such that they are arranged at a distance from one another. The method also comprises electrically conductively connecting 2000 the battery cells 10 to one another such that the battery pack 20 acts as a single battery. Furthermore, the method comprises introducing 3000 a stabilizing agent between the spaced-apart battery cells such that the stabilizing agent can withstand a compressive force of up to 500 N Newtons, preferably 1000 Newtons and more preferably 5000 Newtons, acting externally on the battery pack 20. Fig. 4 shows a schematic representation of a proposed device according to a further exemplary embodiment of the invention. Fig. 4 shows a cylindrical battery cell 10 having a positive electrode 12, a negative electrode 14, a separator 16, an electrolyte 18 and a primer 19 located at least on parts of the outer wall of the cylindrical battery cell 10. Fig. 5 shows a schematic representation of a proposed device according to a further exemplary embodiment of the invention. Fig. 5 shows a battery pack 20 comprising a plurality of cylindrical battery cells 10 according to the invention, as shown, for example, in Fig. 4. Fig. 6 shows a schematic representation of a proposed device according to a further exemplary embodiment of the invention. Fig. 6 shows a motor vehicle 30 having at least one battery pack 20 according to the invention, as shown for example in Fig. 5. List of reference symbols 10 Cylindrical battery cell 11 Battery cell blank 12 positive electrode 14 negative electrode 16 Separator 18 Electrolyte 19 Primers 20 battery packs 30 motor vehicles 100 Providing a cylindrical battery cell 200 Applying corrosion protection 300 Applying a primer to at least parts of the outer wall 400 Closing the battery cell 500 Filling the battery cell with a Electrolytes 1000 Arranging a plurality of cylindrical Battery cells 2000 Electrically conductive connection of the Battery cells together 3000 Introduction of a stabilizing agent between the spaced-apart battery cells

Claims

Patent claims 1. A method for producing a cylindrical battery cell (10), the method comprising the following steps: a) providing (100) a cylindrical battery cell blank (11) with an outer wall which comprises steel; b) applying (300) a primer (19) to at least parts of the outer wall; c) closing (400) the battery cell blank (11) by means of laser welding or crimping; d) filling (500) the battery cell blank (111) with an electrolyte (18).

2. The method according to claim 1 further comprising: e) applying (200) a corrosion protection, preferably comprising at least one selected from the group consisting of nickel, zinc, chromates, preferably nickel, wherein step e) takes place before step b).

3. The method according to one of the preceding claims, wherein the primer (19) is applied at least on the closure side of the battery cell blank (11).

4. The method according to any one of the preceding claims, wherein the primer (19) comprises at least one silane-based adhesion promoter, for example N-2-aminoethyl-3-aminopropyltrimethoxysilane.

5. A method for manufacturing a battery pack (20), the method comprising: Arranging (1000) a plurality of cylindrical battery cells (10) such that they are arranged at a distance from one another; Electrically conductively connecting (2000) the battery cells (10) to one another such that the battery pack (20) acts as a single battery; introducing (3000) a stabilizing agent between the spaced-apart battery cells (10) such that the stabilizing agent withstands a compressive force of up to 500 Newtons, preferably up to 1000 Newtons and more, preferably up to 5000 Newtons, acting externally on the battery pack (20).

6. The method of claim 5, wherein the stabilizing agent comprises a foam.

7. The method of claim 6, wherein the foam is a polyurethane foam.

8. A cylindrical battery cell (10) comprising: a positive electrode (12); a negative electrode (14); a separator (16); an electrolyte (18); and a primer located at least on parts of the outer wall of the cylindrical battery cell (10).

9. A battery pack (20) comprising a plurality of cylindrical battery cells (10) according to claim 8.

10. A motor vehicle (30) comprising at least one battery pack (20) according to claim 9.