DE202017101961U1 - Traktionsakkumulator, in particular elongate design with adjacently arranged lithium-ion secondary cells - Google Patents

Abstract

Traktionsakkumulator (1, 1, 1, 101) with stacked, prismatic electrochemical secondary cells (3, 3, 3, 3) having a rectangular, elongated basic shape (5, 105) in a section, wherein the basic form (5, 105 ) continues in a width (11) to a conversion volume (21) with active elements (19, 119) stacked parallel to one another, and the volume (21) is part of a module volume (23) of the traction battery (1, 1, 1, 101) characterized in that the basic shape (5, 105) has a threefold length (13) running along at least one long side (7, 7) compared to a height (15) of the basic shape (5, 5) running along a high side (9, 9). 105), and that a cut surface resulting from the cut has at least 80% an active surface (19, 119), ideally more than 92% an active surface (19, 119), and / or an active surface (19) 19, 119) by width (11) resulting active volume (21) at least 60% of the module volume (23), ideally more than 62% of the module volume (23).

Description

The present invention deals with a traction accumulator of an elongated design in which the secondary cells, like lithium-ion secondary cells, form an accumulator module next to one another. In other words, the present invention relates to a traction battery, in particular for a motor vehicle such as a passenger car, according to the preamble of claim 1.

Technical area

• • der gewünschten hohen Energiedichte (gemessen z. B. in Wh pro Liter Batterie-Volumen),
• • auf möglichst geringe Gewichte pro elektrischer Kapazität (gemessen z. B. in Kilo pro Farad),
• • auf eine möglichst ausgeglichene Wärmeleitfähigkeit (gemessen z. B. in Watt pro Meter und Kelvin) und
• • auf einen akzeptablen Temperaturgradient (gemessen z. B. in Kelvin pro Meter).

From the literature and by small series are electric vehicles, especially for road use, known that a larger number of secondary electrochemical cells, preferably on lithium-ion basis, to a high-voltage (eg, 400 volts to 850 volts) power source electrically and mechanically join together. The focus in the development of suitable traction batteries, among other things, on the technical difficulties

• The desired high energy density (measured, for example, in Wh per liter of battery volume),
• • on the lowest possible weights per electrical capacity (measured eg in kilos per farad),
• • the most equalized thermal conductivity (measured, for example, in watts per meter and Kelvin) and
• • to an acceptable temperature gradient (measured eg in Kelvin per meter).

Traction batteries still the difficulty arises that this, they should be z. B. are installed in a passenger vehicle, as mechanically stable as possible, in particular to perform torsionally stiff. The claims are at least partially contradictory. Mechanically stable traction batteries are usually heavier and therefore have a lower energy density per gram than lighter accumulators, eg. B. in the field of consumer electronics.

The present invention is in the field of traction batteries with the theme of how to switch an accumulator module that represents an acceptable compromise between the conflicting requirements.

A secondary cell design presented in numerous publications is the prismatic cell, which is often used for lithium ion accumulators in the mobile sector, such as in the automotive sector. Due to the desired short charging times for charging a Traktionsakkumulators considerations are made as the heat generated during the charging of the accumulators can be discharged as low as possible.

In this case, it can be considered which of the types of accumulators of which it u. a. Such types as pouch cells, prismatic cells and hard-cover modules are the most promising candidates for optimized design. The individual types can be represented by the patent literature.

State of the art

The US 2014/154 549 A1 (Applicant: GrafTech International Holdings, Inc., filing date: Aug. 13, 2012) shows a heatsink stack assembly to which heat is to be supplied from the accumulator cells via thermal transfer sheets. Again 1 of the US 2014/154 549 A1 can be seen, a mechanical strength of the stack is only produced by a frame-like housing.

The US 2016/049 704 A1 (Applicant: GrafTech International Holdings Inc., priority date: 04.06.2012) describes a stacked arrangement of prismatic shaped accumulators, which are unilaterally mounted in a heat sink clamped by heat distribution plates to transfer the resulting heat when charging on the heat sink. The cells (secondary cells) shown in the figures are also referred to in the art as pouch cells due to their laminated packing. The cells themselves are made of a material that does not focus on mechanical stability but rather on electrochemical functionality. Therefore, in the US 2016/049 704 A1 proposed stacks due to the inter alia flexible graphite layer not be particularly mechanically stable.

The US 2016/056 427 A1 (Applicant: LG Chem, Ltd., filing date: 15.05.2013) also starts from the pouch cells, wherein between two pouch cells a stabilizing cartridge frame is arranged on the entire surface between the two cells. That is, the mechanical stability is generated by the multiple use of stabilizing frames.

The DE 603 08 598 T2 (Patent owner: Nissan Motor Co., Ltd., Grant Date: 27.09.2006), also published as EP 1 376 718 A2 , deals with pouch cells. These are optimized in their dimensions according to various criteria. Nearly countless variants for individual dimensions, in particular also tabular, are listed here. A reader of EP 1 376 718 A2 So come on the different proportions, without knowing which proportion is actually to give preference in pouch cells.

The US 8 231 996 B2 (Patent owner: Keith Howard, Sheau-Pyng Lin, grant day: 20.08.2009) deals with round cells and offered for these cells allegedly suitable dimensions and ratios.

In the DE 10 2009 046 801 A1 (Applicant: SB LiMotive Company Ltd., Disclosure date: 19.05.2011) describes a battery cell in which a length belonging to a base surface is larger than that through the side surface at least in an extent to be the maximum extension defined height of the battery cell body. The bottom surface should serve as a contact surface for a connected cooling. Terminals of the battery cell can be arranged on two opposite side surfaces. On the side surface is also a bursting pressure opening, preferably below the terminal and provided with a valve. A division of the battery cell by partitions in cell units serves to conduct heat through the partitions from the interior to the surface of the battery cell.

The DE 10 2005 031 504 A1 (Applicant: DaimlerChrysler AG; Disclosure Date: 11.01.2007) is working on a lithium-based traction battery that focuses on the heatsink for a stack of prismatic modules. The individual cells inside a module are separated by webs. In each of the webs a recess is arranged. Cooling ribs connected to a central heat sink should protrude into the recesses of the webs. Due to this design with webs and cooling ribs projecting into them, it should be possible to produce the housings of the individual modules via casting-technical production methods.

A guided around an electrochemical stack outside around, U-shaped cooling plate, as in the US 2014/272 513 A1 (Applicant: GM Global Technology Operations LLC, filing date: 13.03.2013) can increase mechanical stability but also increase the overall weight of the enclosed stack.

A similar approach, but not with a liquid coolant, is used in the US 2016/197 386 A1 (Applicant: LG Chem, Ltd., priority date: 28.08.2013) presented in which two cap-like half-housing to completely cover pile-like flat cells, the heat dissipation should be improved by the fact that after assembly through filling openings in the caps a thermoplastic resin in the The interior containing the stack is injected.

The EP 2 064 758 B1 (Patentee: LG Chem, Ltd., priority date: 18.09.2006) depicts in pictures a stack of flat cells covered by electronic boards on three sides instead of a housing, the sides covered with metal plates being provided with a rail system so that two stacks can be pushed together over the rails. The stacks are freely accessible outside of the board or metal plate cover. For intended idling and also operating voltages in the three-digit voltage range, such a modular design is likely to create concerns about the lack of contact safety.

In the two patent applications US 2012/129 024 A1 (Applicant: Cobasys, LLC; priority date: 18.11.2010) and WO 2016/053 403 A1 (Applicant: Johnson Controls Technology Company; priority date: 30.09.2014) shows how individual modules can be mechanically connected to form larger accumulators.

Some of the publications examined describe accumulator packages which are only conditionally suitable for rough use in motor vehicles. In other designs, it acts as if a mechanical stability is bought by components that cause a strong weight increase of the accumulator.

Technical difficulties

There is a need for an arrangement of electrochemical cells that have sufficiently mechanically stable an acceptably low weight per stored energy. Ideal would be an accumulator design, which nevertheless can provide a short charging time thanks to recordable high charging currents and the associated heat development.

invention description

The present invention solves the problem of the invention by a device according to claim 1. Advantageous further developments can be found in the dependent claims.

Traction batteries are such secondary electrochemical cells, d. H. Electrochemical cells that can be charged and discharged multiple times and that are suitable for mobile use in vehicles. Particularly interesting are traction batteries for motor vehicles. These include passenger cars.

The electrochemical secondary cells are available in many types. A possible design are the stacked, prismatic secondary cells. This differs z. For example, the pouch cells presented above.

A type of secondary cell that makes its name through the materials or ions that are incorporated in the secondary cells are the lithium-ion batteries. As a rule, therefore, a material or ion specification for one of the two electrodes of a basic cell of a secondary cell or for an electrolyte is the name giving information. The category of lithium-ion batteries includes a whole group of chemically active, film-like half-cells and suitable electrolytes.

As reference components or as common components, a lithium secondary battery generally includes a positive electrode, a negative electrode, a separator, and a nonaqueous electrolytic solution, e.g. B. may contain lithium salt.

• • erster Schritt Aufbringen einer Mischung aus einem aktiven Material der positiven Elektrode, einem leitfähigen Mittel und einem Bindemittel auf einen positiven Elektrodenstromkollektor und
• • zweiter Schritt Trocknen der Mischung. Ergänzend kann der Mischung nach Bedarf ein Füllstoff zugesetzt werden.

The positive electrode can be created, for example, by the following two steps:

• • first step applying a mixture of a positive electrode active material, a conductive agent and a binder to a positive electrode current collector and
• • second step drying the mixture. In addition, a filler can be added to the mixture as needed.

In the following, common nomenclatures are used to characterize the composition of chemically synthesizable substances in terms of the elements forming the substances and their relative abundance, in particular with regard to their molarity. This information can also be referred to as chemical formulas or molecular formulas of chemical compounds.

• • eine geschichtete Verbindung wie ein Lithiumkobaltoxid (LiCoO₂) oder
• • ein Lithiumnickeloxid (LiNiO₂) oder
• • eine Verbindung, bei der ein oder mehrere Übergangsmetalle ersetzt sind,
• • ein Lithiummanganoxid gemäß einer chemischen Formel Li_1+xMn_2-xO₄ (mit x = 0 bis 0,33) oder
  • • ein Lithiummanganoxid wie LiMnO₃, LiMn₂O₃ oder LiMnO₂,
  • • ein Lithiumkupferoxid (Li₂CuO₂;),
  • • ein Vanadiumoxid wie LiV₃O₈, LiFe₃O₄, V₂O₅ oder Cu₂V₂O₇,
  • • ein auf Ni basierendes Lithium-Nickel-Oxid, gemäß einer chemischen Formel LiNi_1-xM_xO₂ (wobei M = Co, Mn, Al, Cu, Fe, Mg, B oder Ga und x = 0,01 bis 0,3 ist),
  • • ein Lithium-Mangan-Verbundoxid gemäß einer chemischen Formel LiMn_2-xM_xO₂ (wobei M = Co, Ni, Fe, Cr, Zn oder Ta und x = 0,01 bis 0,1 ist) oder einer chemischen Formel Li₂Mn₃MO₈ (wobei M = Fe, Co, Ni, Cu oder Zn ist),
  • • LiMn₂O₄, wobei Li in einer chemischen Formel teilweise durch Erdalkalimetallionen ersetzt ist,
  • • eine Disulfidverbindung oder
  • • Fe₂(MoO₄)₃.

The active material of the positive electrode may, for. One or more of the following:

• A layered compound such as lithium cobalt oxide (LiCoO ₂ ) or
• • a lithium-nickel oxide (LiNiO ₂ ) or
• • a compound in which one or more transition metals have been replaced,
• A lithium manganese oxide according to a chemical formula Li _{1 + x} Mn _2-x O ₄ (where x = 0 to 0.33) or
  • A lithium manganese oxide such as LiMnO ₃ , LiMn ₂ O ₃ or LiMnO ₂ ,
  • A lithium copper oxide (Li ₂ CuO ₂ ;),
  • A vanadium oxide such as LiV ₃ O ₈ , LiFe ₃ O ₄ , V ₂ O ₅ or Cu ₂ V ₂ O ₇ ,
  • A Ni-based lithium-nickel oxide according to a chemical formula LiNi _1-x M _x O ₂ (where M = Co, Mn, Al, Cu, Fe, Mg, B or Ga and x = 0.01 to 0 , 3 is),
  • A lithium-manganese composite oxide according to a chemical formula LiMn _2-x M _x O ₂ (where M = Co, Ni, Fe, Cr, Zn or Ta and x = 0.01 to 0.1) or a chemical formula Li ₂ Mn ₃ MO ₈ (where M = Fe, Co, Ni, Cu or Zn),
  • LiMn ₂ O ₄ , where Li in a chemical formula is partially replaced by alkaline earth metal ions,
  • • a disulfide compound or
  • • Fe ₂ (MoO ₄ ) ₃ .

• • Graphit, wie natürlicher Graphit oder künstlicher Graphit,
• • Ruß bzw. Industrie-Ruß, auch bekannt unter der englischen Bezeichnung „carbon black“,
• • Spaltruß, wie z. B. Acetylen-Schwarz, Ketjen-Schwarz, Channelruß, insb. Kanal-Schwarz,
• • Furnaceruß, wie z. B. Ofen-Schwarz,
• • Flammruß, wie z. B. Lampen-Schwarz, oder Summer-Schwarz,
• • Gasruß,
• • leitfähige Faser(n), wie Kohlenstofffaser(n) oder Metallfaser(n),
• • metallisches Pulver, wie Kohlenstofffluoridpulver, Aluminiumpulver oder Nickelpulver,
• • leitfähige Whisker, wie Zinkoxid oder Kaliumtitanat,
• • leitfähiges Metalloxid, wie Titanoxid.

Conductive average, depending on the addition, is optionally 1 to 30% by weight, based on the total weight of the compound, including the positive electrode active material. The conductive agent should in particular have a high conductivity. The conductive agent is selected so as to induce no chemical change in a battery to which the conductive agent is applied. They are suitable, for example

• Graphite, such as natural graphite or artificial graphite,
• Soot or industrial soot, also known by the name "carbon black",
• • Split shot, such as Acetylene Black, Ketjen Black, Channel Black, esp. Channel Black,
• • furnace carbon black, such as B. oven black,
• • Flammruß, such. B. lamp black, or buzzer black,
• • gas soot,
• Conductive fiber (s), such as carbon fiber (s) or metal fiber (s),
• Metallic powder, such as carbon fluoride powder, aluminum powder or nickel powder,
• Conductive whiskers, such as zinc oxide or potassium titanate,
• Conductive metal oxide, such as titanium oxide.

Conductive materials, such as polyphenylene derivatives, can be used as a conductive agent.

• • Polyvinylidenfluorid,
• • Polyvinylalkohol,
• • Carboxymethylcellulose (CMC),
• • Stärke,
• • Hydroxypropylcellulose,
• • regenerierte Cellulose,
• • Polyvinylpyrrolidon,
• • Tetrafluorethylen,
• • Polyethylen,
• • Polypropylen,
• • Ethylen-Propylen-Dien-Terpolymer (EPDM),
• • sulfoniertes EPDM,
• • Styrol-Butadien-Kautschuk,
• • Fluorkautschuk und
• • verschiedene Copolymere.

The binder is a component that forms the bond between the active material and the conductive agent and the connection to the current collector. The binder is generally used in an amount of from 1 to 30% by weight, based on the total weight of the compound, including the positive electrode active material. As examples of the binder may be mentioned:

• Polyvinylidene fluoride,
• • polyvinyl alcohol,
• Carboxymethylcellulose (CMC),
• • Strength,
• Hydroxypropyl cellulose,
• Regenerated cellulose,
• • polyvinylpyrrolidone,
• • tetrafluoroethylene,
• • polyethylene,
• • polypropylene,
• Ethylene-propylene-diene terpolymer (EPDM),
• Sulphonated EPDM,
• Styrene-butadiene rubber,
• • fluororubber and
• • different copolymers.

The filler is an optional component used to inhibit the expansion of the positive electrode. There is no particular limitation on the filler as long as it does not cause chemical changes in a battery to which the filler is applied and it comprises or is made of at least one fibrous material. Examples of the filler are olefin polymers such as polyethylene and polypropylene, as a fibrous material or fibers may, for. As glass fiber or carbon fiber into consideration.

The negative electrode can be produced by applying a negative electrode active material to a negative electrode current collector and drying it. Optionally, the components described above may be selectively added to the negative electrode active material to further enhance their properties.

As the active material of the negative electrode, for example, carbon may be used, such as. Non-graphitizing carbon or graphite-based carbon, a metal composite oxide such as Li _x Fe ₂ O ₃ (0 ≦ x ≦ 1), Li _x W0 ₂ (0 ≦ x ≦ 1), Sn _x Me _{1 -x} Me _'y O _z (The components are, for example, with a selection from the following in more detail be determined: Me as Mn, Fe, Pb, Ge; Me'. as Al, B, P, Si, group 1, 2, and 3 elements of the periodic table, halogen; 0 ≦ x ≦ 1; 1 ≦ y ≦ 3; 1 ≦ z ≦ 8), lithium metal, lithium alloys, silicon-based alloys, tin-based alloys, metal oxides such as SnO, SnO ₂ are also suitable , PbO, PbO ₂ , Pb ₂ O ₃ , Pb ₃ O ₄ , Sb ₂ O ₃ , Sb ₂ O ₄ , Sb ₂ O ₅ , GeO, GeO ₂ , Bi ₂ O ₃ , Bi ₂ O ₄ or Bi ₂ O ₅ , conductive polymer such as polyacetylene, or a Li-Co-Ni based material.

This makes it possible to combine suitable materials for the desired fields of application in order to design the electrodes particularly efficiently.

The separator is disposed between the positive electrode and the negative electrode. As the separator, for example, an insulating thin film having high ion permeability can be used. Preferably, the thin film has a high mechanical strength. In preferred embodiments, the separator may optionally have a pore diameter of 0.01 μm to 10 μm. Particularly advantageous is a thickness of the separator optionally between 5 microns to 300 microns. As the material for the separator, for example, an olefin polymer is usable. The material may be provided as a sheet or as a nonwoven fabric. Particularly advantageous is polypropylene, which has chemical resistance and hydrophobicity. Favorable properties for the separator include glass fiber (s) or polyethylene. In embodiments in which a solid electrolyte such as a polymer is used as the electrolyte, the solid electrolyte may also function as a separator.

The nonaqueous electrolyte solution with lithium salt comprises a polar organic electrolyte solution and at least one salt of lithium. As the electrolytic solution, a nonaqueous liquid electrolytic solution, an organic solid electrolyte or an inorganic solid electrolyte may be used. The electrolyte may have chemically different components

As examples of the nonaqueous liquid electrolytic solution, non-protic organic solvents such as N-methyl-2-pyrrolidinone, propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, gamma-butyro-lactone, 1,2-dimethoxyethane, tetrahydroxy-franc, 2-methyltetrahydrofuran, dimethyl sulfoxide, 1,3-dioxolane, formamide, dimethylformamide, dioxolane, acetonitrile, nitromethane, methyl formate, methyl acetate, phosphoric acid triester, trimethoxymethane, dioxolane derivatives, sulfolane, methylsulfolane, 1,3-dimethyl-2-imidazolidinone, propylenecarbonate derivatives, tetrahydrofuran derivatives, Ether, methyl propionate and ethyl propionate may be mentioned.

As examples of suitable organic solid electrolytes may be mentioned polyethylene derivatives, polyethylene oxide derivatives, polypropylene oxide derivatives, phosphoric acid ester polymers, polyreaktionslysine, polyester sulfide, polyvinyl alcohols, polyvinylidene fluoride and polymers having ionic dissociation groups.

As examples of suitable inorganic solid electrolytes, nitrides, halides or sulfates of lithium (Li) with common chemical abbreviations for their composition such as Li ₃ N, LiI, Li ₅ NI ₂ , Li ₃ N-LiI-LiOH, LiSiO ₄ , LiSiO ₄ - LiI-LiOH, Li ₂ SiS ₃ , Li ₄ SiO ₄ , Li ₄ SiO ₄ -LiI-LiOH and Li ₃ PO ₄ -Li ₂ S-SiS ₂ .

The lithium salt is a material which is easily soluble in the above-mentioned nonaqueous electrolytes. The lithium salt may for example comprise one or more of the following: LiCl, LiBr, LiI, LiClO ₄ , LiBF ₄ , LiB ₁₀ Cl ₁₀ , LiPF ₆ , LiCF ₃ SO ₃ , LiCF ₃ CO ₂ , LiAsF ₆ , LiSbF ₆ , LiAlCl ₄ , CH ₃ SO ₃ Li, CF ₃ SO ₃ Li, (CF ₃ SO ₂ ) ₂ NLi, chloroborane lithium, lower aliphatic carboxylic acid lithium, lithium tetraphenylborate and imido compounds.

With a selection of the above-mentioned materials for electrolytes, the electrolyte can be adjusted particularly well to the selected electrode material. As a result, good operating characteristics, such as favorable charge / discharge characteristics for batteries or electrical energy storage cells, adjustable.

In addition, pyridine, triethyl phosphite, triethanolamine, cyclic ethers, ethylenediamine, n-glyme, hexaphosphoric triamide, nitrobenzene derivatives, sulfur, chinonimine dyes, N-substituted oxazolidinone, N, N-substituted imidazolidine, for example, can further improve the charge and discharge properties and as flame retardants. Ethylene glycol dialkyl ethers, ammonium salts, pyrrole, 2-methoxyethanol, aluminum trichloride or the like of the nonaqueous electrolytic solution. In some circumstances, the non-aqueous electrolyte solution for the high flammability property may additionally contain halogenated solvents such as carbon tetrachloride and ethylene trifluoride. Furthermore, to further improve the high temperature resistance, the nonaqueous electrolytic solution may additionally contain carbon dioxide gas.

The secondary electrochemical cells of the traction battery, which are in particular lithium-ion cells, are prismatic secondary cells stacked with each other. Not only the cells are stacked with each other, but in the secondary cells are - according to an advantageous embodiment - a first electrode, an active region of the electrolyte and a second electrode over its entire surface, plan and arranged parallel to each other. By a secondary cell, a longitudinal section can be performed. If the cell is cut (mentally), a basic form comes into the foreground, which is rectangular but oblong. A single secondary cell is rod-shaped, almost flat steel-like.

The individual pages of the basic form can be designated by long side, high side and width. The three sides long side, high side and width mark the shape of the single cells. The long side is the longest side on the housing of the secondary cell. At right angles to the long side is the high side. The high side also has a length, which can also be referred to as height. The basic form has two long sides and two high sides. The long side is several times longer than the high side. Due to the stacked arrangement of the individual components of the secondary cell, the secondary cell may have the smallest extent in the direction of its width. Advantageously, the longest side to be observed on the basic shape, at least three times as long as the high side of the basic shape. If the active area bounded by the long side and the high side is in depth, i. H. in width, continued, results in a first conversion volume of a single cell. The conversion volumes of the single cell are adjacent to one another, placed parallel to each other. If the conversion volumes are combined, this results in a total module volume of the traction battery.

The section through the secondary cell, which leads to the derivation or the visibility of the basic shape, covers an area of which at least 80% of the total area can be used as the active area. By optimized alignment between the long side and the high side, an active surface can be created covering at least 92% of the total area of the basic shape.

According to a further aspect, the active volume can also be optimized in the individual enveloped secondary cell design. The active volume is the single active area of each individual secondary cell of the traction battery multiplied by the width of the internal components of the secondary cell. The traction battery can be optimized in its dimensions so that at least 60% of the module volume can be used as active volume. By further optimizing the ratio between long, high and width, module volumes of more than 62%, in some embodiments, even more than 65% active volume of total module volume (i.e., 60% to more than 65% of module volume) can be created.

In the following, advantageous embodiments and developments are set forth, which in themselves, both individually and in combination, can also disclose inventive aspects.

For electrical conduction at least two pole lugs are placed in the region of the high sides directly on the active surfaces. A suitable method for producing an electrical connection is a welding process.

It may be emphasized that each individual secondary cell has its own housing. Although the enclosures take up space in the module volume and thus reduce the active volume (superficially), the housings provide numerous advantages: mechanical stability, parallelism, favorable thermals etc. As a result, it means that the housings can increase the utilization of the module volume.

Over the pole lugs and over - arranged in the following - electrical lines, an electric current in the central region, d. H. each in the region of the high sides transverse to the reaction surface of the active surfaces derived. The electrical lines are arranged transversely to the active surface.

The space of the module volume immediately adjacent to the pole lugs, of which a pole lug is a positive pole and a pole lug is a negative pole, can each be used for a cooling channel (feed cooling channel and discharge cooling channel). The heat-producing active surfaces are cooled in their lateral areas by means of cooling channels.

At least two pole lugs are arranged laterally on the respective active surfaces. The two pole lugs are each one on a high side. The two pole lugs are on opposite sides of the active surface. As a fastening technique, the attachment via weld points offers.

The housing of a single cell can be made of a metal. Metals which are suitable for this purpose are, for. As aluminum or stainless steel. The housings can be made of aluminum or stainless steel. Due to the shape of the housing, it is possible to manufacture the metal housing as extruded profiles. Such an extruded profile can be cut to the length or broad side of the active surfaces.

The housings can be designed to save space. The housings can be designed so narrow that the housing in one cut only the active area by about 2% to the outside. The active area has a height. 2% of this length of height corresponds to the thickness of the housing.

In order to leave the temperature as uniformly distributed over the active surfaces, z. B. despite a fast charge by means of a very high charging current (eg., The 3 to 4 times the maximum load current), cooling measures can be taken. The shape of the Traktionsakkumulatoren or the individual cells offers the opportunity to interchange cooling plates between two single cells. If sufficient cooling is required, a cooling plate can be inserted after each individual cell. Such cooling plates can be realized as sandwich cooling plates. The sandwich function of the cooling plate is due to an internally guided cooling channel design. Sandwich cold plates can z. B. be formed from a double-walled sheet. Another option is to take two plastic half-shells that are glued or welded. As a result, a cavity is created between the layers of the cooling plate, which can be flowed through with cooling medium. Particularly favorable are liquid cooling media, such. As a glycol-water mixture or a refrigerant. The cooling capacity can be further increased when the liquid cooling medium is circulated, z. B. via a liquid pump for the glycol mixture.

The heat output or the heat output of the sandwich cooling plate can be increased if more than two cooling channels are arranged in the sandwich cooling plate. Advantageously, the cooling channels are arranged in a central region of the sandwich cooling plate. The sandwich cooling plate has two or more cooling channels, which run longitudinally, especially in a central region, as seen on the high side of the cooling plate. The cooling channels extend in this embodiment parallel to the long side, which is known from the shape of the basic shape.

It has been found to be beneficial to group together between ten (10) and forty (40) secondary cells with their respective active areas to form a battery pack in a module housing. The number of cells, such as. B. 20 cells is clamped by the module housing. There is a compression on the single cells instead.

The respective secondary cells of a strand are connected in series with each other. In a module housing is at least one strand with series-connected secondary cells.

The secondary cells can be supported by a carrier plate. As a support plate lends itself to the bottom plate of the accumulator. The module housing has a plate, which can be used as a support plate at the same time.

The support plate can also be a cooling plate. The Traktionsakkumulator has a thermal exchange surface, which is offered by the carrier plate. The support plate is that part of the module housing which is intended to be installed at the lowest point in the vehicle.

The module housing can be realized with individual tension elements, so that the arranged inside the module housing secondary cells are compressed by the module housing. Also by the double wall, ie the wall of the Module housing and the wall of a single cell, a total compression can be made using the E-modulus of the material of the housing and the E-module of the material of the module housing. The swelling or expansion in the course of charge / discharge cycles or the expansion in the course of aging or the expansion in the course of the storage of water, which is generated by all the stacked secondary cells in total, can by train systems or tie rods and / or by E-modules of bezels, such. B. housing walls are intercepted.

The housing need not be kept constant over its circumference, but the module housing can be configured with different thicknesses. For example, the carrier plate may be thicker than the lid. Likewise, the housing can be designed for the respective secondary cell with different thicknesses. This saves even more weight.

The proposed form of a Traktionsakkumulators is characterized by high volumes of active. Also, the presented Traktionsakkumulator offers a favorable energy density-per-weight ratio.

list of figures

• 1 eine seitliche Ansicht einer Einzelzelle mit einem (sichtbaren) Kontakt zeigt,
• 2 eine Einzelzelle aus einer im 90°-Winkel querverlaufenden Perspektive (im Vergleich mit 1) zeigt,
• 3 einen Schnitt A - A durch die Einzelzelle nach 1 zeigt,
• 4 Außenumrisse einer Einzelzelle mit ihrem Zellengehäuse zeigt,
• 5 einen Stapel wechselweise gegensätzlich zueinander orientierter Einzelzellen zur Bildung eines Moduls zeigt,
• 6 eine erste Ausführungsform eines Moduls zeigt,
• 7 eine zweite Variante eines Moduls zeigt,
• 8 das Modul aus 7 aus einer Perspektive von oben zeigt,
• 9 das Modul nach 7 in einer teilgeöffneten Darstellung zeigt,
• 10 eine weitere Ausführungsform einer Einzelzelle im Modulgehäuse zeigt,
• 11 eine Kühlplatte in einem Modulgehäuse zeigt,
• 12 eine Ausführungsvariante eines Stapels zeigt, der sich aus Einzelzellen nach 10 zusammensetzen kann,
• 13 ein Gehäuse eines Moduls von oben zeigt,
• 14 ein Modulgehäuse in einer isometrischen Darstellung zeigt und
• 15 ein teilgeöffnetes Modul zeigt.

The present invention may be better understood by reference to the accompanying drawings, wherein: FIG

• 1 shows a side view of a single cell with a (visible) contact,
• 2 a single cell from a transverse perspective at 90 ° (in comparison with 1 ) shows,
• 3 a section A - A by the single cell after 1 shows,
• 4 Outside outlines of a single cell with its cell housing shows
• 5 shows a stack of mutually oppositely oriented single cells to form a module,
• 6 shows a first embodiment of a module,
• 7 shows a second variant of a module,
• 8th the module off 7 from a perspective from above,
• 9 the module after 7 in a partially opened illustration shows
• 10 shows a further embodiment of a single cell in the module housing,
• 11 shows a cooling plate in a module housing,
• 12 shows an embodiment of a stack, which is made up of individual cells 10 can put together
• 13 shows a housing of a module from above,
• 14 shows a module housing in an isometric view and
• 15 a partially opened module shows.

list of figures

• 1 shows a first embodiment of a single cell 53 with her cell case 31 where the first contact 47 is appropriate. Such single cells as the single cell 53 can stack a traction accumulator such as the traction accumulator 1 ^II to 9 form. Every single cell 53 has a width 11 passing through the width of the cell case 31 is determined. The shape of the single cell 53 and thus the shape of the cell case 31 is when from the in 1 shown side view of the cell housing 31 is looked at, oblong and upright. Will the single cell 53 along the in 1 shown section line A - A cut, the results in 3 illustrated sectional drawing of the cell housing 31 , The width 11 is narrower than the length 15 the high side 9 ,
• 2 shows the cell case 31 from a front view of the single cell 53 , In this view, the basic form is good 5 the single cell 53 , due to the dimensions of the cell housing 31 to recognize. The basic form 5 is a beam-like, oblong, rectangular shape. The long side 7 is longer than the high side 9 , The contacts 47 . 49 sit sideways, on the edge of the cell case 31 , The contacts 47 . 49 limit the highsides 9 to each end of the cell case 31 , This means that in the prismatic cell shape of the single cell 53 two contacts 47 . 49 are present, one contact each 47 . 49 on its high side 9 , The prismatic cell shape of the single cell 53 has two high sides 9 , The contacts 47 . 49 sit eccentrically placed on the length 15 the high side 9 ,

As I said, the cell case 31 to 2 approximately in the middle of its width 11 (S. 1 ) cut (cutting line AA ), results in a (simplified schematic) view 3 , The cell case 31 summarizes by its basic form 5 in a rectangular way, the active surface 19 one. The cell case 31 represents the boundary and borders on the outside or on the outside 51 from. The active area 19 gets through the cell case 31 opposite the outside 51 limited. The active area 19 has a length 13 that is a multiple of the height 15 is. The length 13 the long side 7 is through the contacts 47 . 49 outward 51 extended. The contacts 47 . 49 are located on the high sides 9 , The housing 31 the cells have different thicknesses 69 . 69 ^I on.

In 4 is the cell case 31 the single cell 53 with their contacts 47 . 49 shown as a narrow, oblong, rectangular box enclosing the active area. Part of the conversion volume 21 is from every single cell 53 made available. Becomes the active area 19 (please refer 3 ) in the width 11 (see. 1 ), this results in the (total) conversion volume 21. By the plane-parallel arrangement of the electrodes and of the electrolyte over the entire active area 19 away, is the internal volume of the cell case 31 with the conversion volume 21 the single cell 53 almost completely filled. As a result, active volumes of at least 60% (based on the total volume of Traktionsakkumulators 1 (see. 5 )) produce. At a ratio of more than 3 between long side 7 and high side 9 (S. 2 and 3 ), even active volumes of more than 62%, ideally even more than 65% can be created.

5 shows a module housing 33 with the two collective power conductors 55 . 57 , The collecting conductor 55 . 57 of the traction battery 1 sit at the first and at the last single cell of the single cells 53 . 53 ^I . 53 ^II , The individual cell housing 31 . 31 ^I . 31 ^II are with their surfaces, formed from long side and high side (cf. 3 ), stacked on top of each other around the traction accumulator 1 to build. The single cells 53 . 53 ^I . 53 ^II rest on the support plate 45 , After the collector conductor 57 are the secondary cells 3 . 3 ^I . 3 ^II . 3 ^III piled one at the other fitting present.

6 shows a sectional view through another embodiment of a Traktionsakkumulators 1 ^I , The traction battery 1 ^I can by its mounting rails, such as the mounting rail 59 and the mounting rail 59 ^I , to a vehicle chassis, z. B. in Unterflorbereich be attached. For this purpose, the module housing side wall 61 the mounting rail 59 on. The module housing 33 is composed of plate-like elements. The module housing 33 has a module housing bottom 63 where the module housing side wall is located 61 followed. The module housing 33 is from the module housing cover 65 limited to the top. The active area 19 gets off her pole banners 25 , 27 laterally closed. The pole flags 25 . 27 are in the middle area 17 . 17 ^I the active area 19 , The first pole flag 25 goes into the first contact 47 above. The second pole flag 27 goes into the second contact 49 above. Laterally on the active surfaces 19 of the single cells 53 . 53 ^I . 53 ^II (S. 5 ) close the individual contacts 47 . 49 at. The mounting rail 59 is located on the module housing side wall 61 in an upper area of the module housing side wall 61 , In the same dimension as the long side 7 ^I extends, the exchange surface extends 71 in its longest extent. The exchange surface 71 and the module case bottom 63 are at the traction accumulator 1 ^I identical. The high side 9 ^I is perpendicular to the long side 7 ^I ,

In 7 is a traction accumulator 1 ^II to be seen in 3D. Like the traction accumulator 1 ^I (to 6 ) from the module housing cover 65 is limited to the Traktionsakkumulators 1 ^II from module housing side wall 61 ^I , Module housing bottom 63 ^I , Module housing cover 65 ^I and module housing back wall 67 composed. Outside the edge of the mounting rail 59 ^{II runs} . On the opposite side to the side with the first mounting rail 59 ^II is the second mounting rail 59 ^III arranged.

As in 8th can be seen through the view from above, form the (out 7 known) items module housing side wall 61 ^I , Module housing bottom 63 ^I , Module housing cover 65 ^I and module housing back wall 67 a module volume 23 , The module volume 23 comprises a (nearly) cuboidal, rectangular, oblong, longer than wider, wider than higher encompassing space, by the basic shape 5 (S. 3 ) is determined.

In 9 becomes the traction accumulator 1 ^II to 7 shown in a half-opened variant, reducing the arrangement of the individual cells 53 . 53 ^I . 53 ^II you can see. The single cells 53, 53 ^I . 53 ^II are layered side by side along the module housing side wall 61 ^I one next to the other on the module housing floor 63 ^I arranged. The single cells 53 . 53 ^I . 53 ^II form (essentially) the module volume 23 ,

In the 10 to 15 becomes a variant of a traction accumulator 101 shown on a rectangular basic shape 105 building next to the active areas 119 in the module housing 133 cooling channels 135 . 137 having.

As in 10 can be seen, the single cell 153 through the module housing 133 edged.

In 11 becomes a sandwich cooling plate 139 shown (opened in the middle, ie only one sheet or only one side), which also in the module housing 133 can be arranged. The sectionally parallel cooling channels 141 . 141 ^I . 141 ^II . 141 ^III lead the cooling medium 143 , Also the cooling plate 139 has an elongated, almost identical Basic form 105 in comparison with the basic form 105 the single cell 153 (please refer 10 ). The single cell 153 is in the housing of the cell 131 clamped. The cell case 131 . 131 ^I . 131 ^II offer, as in 12 you can see the contact surfaces for the attachment of the single cells 153 ,

As in 15 you can see that in the 13 shown module housing 133 in open form shows the contacts 147 . 149 adjacent to each other in a line of flight. The contacts 147 . 149 can by welding points 129 be realized.

LIST OF REFERENCE NUMBERS

1, 1 ^I , 1 ^II , 101

Traktionsakkumulator

3, 3 ^I , 3 ^II , 3 ^III

first, second, third, fourth secondary cell

5, 105

Basic form

7, 7 ^I

first, second long side

9, 9 ^I

first, second high side

11

width

13

Length, especially a long side

15

Length, especially a high side

17, 17 ^I

middle area, especially a high side

19, 119

Active surface or active surface

21

conversion volume

23

module volume

25

first pole lug, in particular pole lug of the positive pole

27

second pole lug, in particular pole lug of the negative pole

129

WeldingSpot

31, 31 ^I , 31 ^II , 131, 131 ^I , 131 ^II

cell case

33, 133

module housing

135

first cooling channel

137

second cooling channel

139

Sandwich plate or cooling plate

141, 141 ^I , 141 ^II , 141 ^III

Cooling channel, especially in a sandwich plate

143

Cooling medium such as a refrigerant or a glycol-water mixture

45

support plate

47, 147

first contact

49, 149

second contact

51

Outside

53, 53 ^I , 53 ^II , 153

single cell

55

first collecting conductor

57

second collector conductor

59, 59 ^I, 59 ^II, 59 ^III

mounting rail

61.61 ^I

Module housing sidewall

63.63 ^I

Module housing bottom

65.65 ^I

Module cover

67

Module rear panel

69.69 ^I

thickness

71

exchange area

A-A

cut AA

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been 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

• US 2014154549 A1 [0007]
• US 2016049704 A1 [0008]
• US 2016056427 A1 [0009]
• DE 60308598 T2 [0010]
• EP 1376718 A2 [0010]
• US 8231996 B2 [0011]
• DE 102009046801 A1 [0012]
• DE 102005031504 A1 [0013]
• US 2014272513 A1 [0014]
• US 2016197386 A1 [0015]
• EP 2064758 B1 [0016]
• US 2012/129024 A1 [0017]
• WO 2016/053403 A1 [0017]

Claims (15)

Traktionsakkumulator (1, 1 ^I , 1 ^II , 101) with stacked, prismatic electrochemical secondary cells (3, 3 ^I , 3 ^II , 3 ^III ), which have in a section a rectangular, elongated basic shape (5, 105), wherein the Basic shape (5, 105) in a width (11) to a conversion volume (21) with parallel stratified, active elements (19, 119) continues, and the volume (21) part of a module volume (23) of the Traktionsakkumulators (1, 1 ^I, 1 ^II, 101), characterized in that the basic form (5, 105) is a (at least along one long side 7, 7 ^I) extending three times the length (13) in comparison to a (along a high page 9, 9 ^I) extending height (15) of the basic shape (5, 105), and that a cut surface resulting from the cut constitutes at least 80% an active surface (19, 119), ideally more than 92% an active surface (19, 119) , and / or an active volume (21) resulting from active area (19, 119) by width (11) at least 60% of the module volume (23), ideally to more than 62% of the module volume (23) claimed. Traktionsakkumulator (1, 1 ^I , 1 ^II , 101) after Claim 1 , characterized in that in the region (17, 17 ^I ) of the high sides (9, 9 ^I ) pole lugs (25, 27) on the active surface (19, 119), in particular by welding (129) are connected. Traktionsakkumulator (1, 1 ^I , 1 ^II , 101) according to any one of the preceding claims, characterized in that each secondary cell (3, 3 ^I , 3 ^II , 3 ^III ) individually (53, 53 ^I , 53 ^II , 153) in a own housing (31, 31 ^I , 31 ^II , 131, 131 ^I , 131 ^II ) is encased. Traktionsakkumulator (1, 1 ^I , 1 ^II , 101) according to any one of the preceding claims, characterized in that an electrical line (55, 57) of the current in a central region (17, 17 ^I ) of the high sides (15) transversely to the reaction surface the active surface (19, 119) is arranged. Traction accumulator (1, 1 ^I , 1 ^II , 101) after one of Claims 2 to 4 , characterized in that adjacent to a pole lug of a positive pole (25) and adjacent to a pole lug of a negative pole (27), in particular with approximately the same width as the pole lug, a cooling channel (135, 137) outside the active area (19, 119) is arranged. Traction accumulator (1, 1 ^I , 1 ^II , 101) after one of Claims 2 to 5 , characterized in that the pole lugs (25, 27) on opposite high sides (9, 9 ^I ) on the active surface (19, 119), in particular at welding points (129), are attached. Traction accumulator (1, 1 ^I , 1 ^II , 101) after one of Claims 3 to 6 , characterized in that the housing (31, 31 ^I , 31 ^II , 131, 131 ^I , 131 ^II ) is made of a made of a metal such as aluminum or stainless steel extruded profile. Traction accumulator (1, 1 ^I , 1 ^II , 101) after one of Claims 3 to 7 , characterized in that the housing (31, 31 ^I , 31 ^II , 131, 131 ^I , 131 ^II ) extended by the active surface (19, 119) claimed area by at least two percent to the outside (51). Traktionsakkumulator (1, 1 ^I , 1 ^II , 101) according to any one of the preceding claims, characterized in that a sandwich-cooling plate (139), z. B. from a double-walled sheet and / or from, for. B. by gluing, assembled half-shells made of a plastic material between two adjacent electrochemical secondary cells (3, 3 ^I , 3 ^II , 3 ^III ) is arranged, in particular with an actively circulated liquid cooling medium (143), such as a glycol mixture or a refrigerant, can be flowed through, wherein preferably the sandwich cooling plate (139) in its central region more than two parallel to each other arranged cooling channels (141, 141 ^I , 141 ^II , 141 ^III ), which is parallel to the long side (7, 7 ^I ) the basic shape (5, 105) extend. Traction accumulator (1, 1 ^I , 1 ^II , 101) according to any one of the preceding claims, characterized in that a number of cells between ten and forty secondary cells (3, 3 ^I , 31 ^I , 3 ^III ) with their active surfaces (19, 119) arranged side by side in a module housing (33, 133) are clamped to form a Akkumulatorpakets to produce a series connection of the secondary cells (3, 3 ^I , 3 ^II , 3 ^III ). Traktionsakkumulator (1, 1 ^I , 1 ^II , 101) according to any one of the preceding claims, characterized in that the secondary cells (3, 3 ^I , 31 ^I , 3 ^III ) are supported by a support plate (45). Traktionsakkumulator (1, 1 ^I , 1 ^II , 101) according to any one of the preceding claims, characterized in that the Traktionsakkumulator (1, 1 ^I , 1 ^II , 101) has a thermal exchange surface (71) at its lowest surface to be arranged, in particular formed through the carrier plate (45). Traction accumulator (1, 1 ^I , 1 ^II , 101) after one of Claims 10 to 12 , characterized in that the module housing (33, 133) is a box housing constructed with tension elements, which compresses the secondary cells (3, 3 ^I , 3 ^II , 3 ^III ). Traction accumulator (1, 1 ^I , 1 ^II , 101) after one of Claims 3 to 13 , characterized in that the housing (33, 133), which is produced in particular by an extrusion process, has different thicknesses (69, 69 ^I ) on different sides. Traktionsakkumulator (1, 1 ^I , 1 ^II , 101) according to any one of the preceding claims, characterized in that the Traktionsakkumulator (1, 1 ^I , 1 ^II , 101) is intended for a motor vehicle such as a passenger car and / or the secondary cells (3 , 3 ^I , 31 ^II , 3 ^III ) is equipped with at least one lithium-ion electrode and with a nonaqueous electrolyte.

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