CN219513161U - High-capacity lithium titanate battery - Google Patents
High-capacity lithium titanate battery Download PDFInfo
- Publication number
- CN219513161U CN219513161U CN202222126150.XU CN202222126150U CN219513161U CN 219513161 U CN219513161 U CN 219513161U CN 202222126150 U CN202222126150 U CN 202222126150U CN 219513161 U CN219513161 U CN 219513161U
- Authority
- CN
- China
- Prior art keywords
- active material
- thickness
- negative
- positive
- accommodating space
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- 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
Landscapes
- Battery Electrode And Active Subsutance (AREA)
- Secondary Cells (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
- Primary Cells (AREA)
Abstract
The utility model provides a high-capacity lithium titanate battery, which belongs to the technical field of lithium ion batteries and comprises: a metal shell provided with an accommodating space therein; the positive plate is positioned in the accommodating space and consists of a first base material and at least one positive active material coating; the negative plate is positioned in the accommodating space and consists of a second base material and at least one negative active material coating; at least one isolation film is positioned in the accommodating space and between the positive plate and the negative plate, and the isolation film can separate the positive plate from the negative plate so that the positive plate and the negative plate are not in direct contact with each other. The high-capacity lithium titanate battery provided by the embodiment of the utility model can improve the processes of coating, rolling, cutting and winding in battery manufacturing, is good in use of limited physical volume space, and solves the problem of battery capacity density.
Description
Technical Field
The utility model belongs to the technical field of lithium ion batteries, and particularly relates to a high-capacity lithium titanate battery.
Background
Lithium titanate batteries (Lithium-titanate batteries) are Lithium ion batteries, and the positive electrode material of the batteries generally adopts Lithium cobalt oxide (LiCoO) rich in Lithium ions 2 ) Lithium manganate (LiMn) 2 O 4 ) Lithium nickelate (LiNiO) 2 ) Or lithium ternary (NMC) mixed by the above three materials and other materials (e.g.: NCA, liNi 0.8 Co 0.15 Al 0.05 O 2 ) Etc.; the negative electrode material is lithium titanate.
Referring to fig. 2, the lithium titanate battery a is composed of a positive electrode sheet B, two separator films C, E, and a negative electrode sheet D, wherein the positive electrode sheet B is formed by coating positive electrode active material coatings B1 (e.g., lithium cobaltate material) on both sides of a positive electrode sheet base material B2, the negative electrode sheet D is formed by coating negative electrode active material coatings D1 (e.g., lithium titanate material) on both sides of a negative electrode sheet base material D2, and a separator film C is provided between the positive electrode sheet B and the negative electrode sheet D for insulation. The cylindrical battery is formed by winding a positive electrode sheet B and a negative electrode sheet D, and then placing the wound positive electrode sheet B and negative electrode sheet D in a circular container, wherein the inner edge of the negative electrode sheet D wound for the first circle is lapped on the outer edge of the positive electrode sheet B, so that another layer of isolating film E is required to be added on the inner edge of the negative electrode sheet D.
The conventional lithium titanate battery generally adopts a composition structure, taking a cylindrical battery model 18650 (the battery has a diameter of 18.5 millimeters (mm) and a length of 65 mm) as an example, and matching with fig. 1 for assistance in description, the thickness of the aluminum foil substrate (i.e., the positive plate substrate B2) of the positive plate B is 16±1 micrometers (μm, i.e., 10 -6 m), the thickness of the positive electrode active material coating layer B1 is 39+ -2 μm, the thickness of the aluminum foil base material of the negative electrode sheet D (i.e., the negative electrode sheet base material D2) is 16+ -1 μm, the thickness of the negative electrode active material coating layer D1 is 43+ -2 μm, the thickness of the separator C, E is 16+ -1 μm, so that the total thickness of the positive electrode sheet B, the negative electrode sheet D and the two-layer separator C, E is 228+ -12 μm, andthe total capacity of the single cell was about 1300 milliamperes (mAh) with a volumetric energy density of 233 watt hours per liter (Wh/L).
The thickness of the aluminum foil base material and the isolating film is reduced, so that the ineffective volume occupied by the active substances can be reduced; and the thickness of the anode and cathode material coating is increased, so that the effective volume ratio of the active substances can be improved. As with the semiconductor process, the capacity density of the battery can be continuously improved only by breaking through the limitation of the manufacturing process and continuously improving the development of the production control. In the process of coating and rolling the anode and cathode materials, in order to enable the pole piece to achieve certain flatness, the pole piece can be stretched from a feeding roller and a receiving roller, if the thickness of the aluminum foil is too thin, the aluminum foil is easy to tear due to lateral shearing stress generated by stretching, and the bottleneck that the anode and cathode pieces of the lithium titanate battery cannot adopt thinner aluminum foil base materials nowadays is the problem.
In addition, when the pole piece is cut, the cutter is required to cut the aluminum foil base material and the double-sided active substance coating coated on the aluminum foil base material, and because of the influence of the hardness of the coating, when the shearing stress of the upper disc cutter and the lower disc cutter is larger than the binding force between coating particles, the crack of the coating material is caused, and the peeling and the powder falling phenomenon are caused, meanwhile, the pole piece base material is also damaged by the shearing force, sharp bursting is generated at the cutting edge of the aluminum foil, especially the bursting degree of the positive pole lithium cobalt oxide material is particularly high, larger cutting force is required, larger bursting is caused by larger cutting shearing stress, and if the thickness of the isolating film is too thin, after the positive pole piece and the negative pole piece are wound with the isolating film, the aluminum foil burrs puncture the isolating film and are short-circuited with the adjacent negative pole piece, so that the main reason that the thickness of the isolating film of the lithium titanate battery cannot be reduced at present is provided.
In summary, the thickness of the anode and cathode material coating is limited by the limits of the pole piece coating, rolling, cutting, etc., and the prior art is often improved by various means including: adding an adhesive to increase the thickness of the coating, and a conductive agent to maintain the conductivity of the thickened coating; in addition, the pole piece formula is adjusted to soften the pole piece, keep the cutting knife opening sharp, adopt negative pressure dust collection and the like when winding, and can remove burrs or suspended particulate matters on the pole piece, however, the prior art is very exhaustive, how to find out the optimal proportion of the thickness of the positive electrode coating and the negative electrode coating, so that the reaction of the positive electrode active matters and the negative electrode active matters reaches the most sufficient reaction, the key point for improving the capacity density of the battery is that the existing lithium titanate battery industry mostly adopts an error method (three and error) to allocate the relative thickness of the positive electrode coating and the negative electrode coating, so that redundant materials are wasted, and meanwhile, the optimal total capacity density cannot be achieved.
Compared with lithium ion batteries such as lithium cobaltate, lithium ternary lithium, lithium iron phosphate and the like, the lithium titanate battery has the advantages of high safety, quick charge, long service life, suitability for low-temperature environment and the like, however, the nominal voltage of the battery is 2.4 volts (V), and the disadvantage of low capacity density of the battery is caused, so that the capacity density of the lithium titanate battery is improved, and the lithium titanate battery is in competition.
Factors affecting the overall capacity density of a battery are largely divided into two parts, namely the chemical nature of the material and the physical volume. In order to improve the capacity density of the battery, early lithium titanate batteries have been started in laboratories from the improvement of materials and additives, the weight capacity density of the lithium titanate material is gradually improved to 160 milliamp hours per gram (mAh/g), the theoretical value is very close to 175mAh/g, and the subsequent space capable of being improved is very limited in the aspect of the chemical characteristics of the lithium titanate material.
Manufacturers with lithium titanate battery manufacturing practices are rare relative to other lithium ion battery manufacturers, besides theory on material characteristics, various characteristic data and control parameters of production are limited, and most of possible methods are tried to be searched by respective manufacturing experiences, and complete system research is not needed. The battery monomer is formed by combining an anode, a cathode, a separation film, electrolyte, a container and the like, and mainly occupies the volume: since the aluminum foil substrate (collector) and the positive electrode active material coating (active material) of the positive electrode sheet, the aluminum foil substrate and the negative electrode active material coating of the negative electrode sheet, and the separator (separator), it is critical to determine the capacity density of the battery to improve the processes of coating, rolling, cutting, and winding in battery manufacturing, and to improve the limited physical volume space, in addition to the capacity density corresponding to the chemical characteristics of the positive and negative electrode materials themselves.
Disclosure of Invention
Aiming at the defects of the prior art, the technical problem to be solved by the embodiment of the utility model is to provide a high-capacity lithium titanate battery.
In order to solve the technical problems, the utility model provides the following technical scheme:
a high capacity lithium titanate battery comprising:
a metal shell provided with an accommodating space therein;
the positive plate is positioned in the accommodating space and consists of a first base material and at least one positive active material coating;
the negative plate is positioned in the accommodating space and consists of a second base material and at least one negative active material coating;
at least one isolating film located in the containing space and between the positive plate and the negative plate, wherein the isolating film can separate the positive plate from the negative plate so that the positive plate and the negative plate are not in direct contact with each other;
and an electrolyte, which is a solution filled in the accommodating space and can transfer metal ion substances in the accommodating space;
wherein the thickness of the positive electrode active material coating layer is 37+ -2 μm, the thickness of the negative electrode active material coating layer is 63+ -2 μm, and the thickness of the separator is 9+ -1 μm.
As a further improvement of the utility model: the first base material and the second base material are made of aluminum foil.
As a further improvement of the utility model: the thickness of the first substrate and the second substrate is 10+/-1 mu m,
the thickness of the pole piece composition of the high-capacity lithium titanate battery is 238+/-12 mu m,
the positive electrode sheet and the negative electrode sheet have an effective volumetric energy density greater than 310 watt hours/liter.
As a further improvement of the utility model: the positive electrode sheet and the negative electrode sheet are respectively applied to the positive electrode sheet and the negative electrode sheet by a rolling machine, the tensile force is 6.7+/-0.3 megapascals, and the gradient of the tensile horizontal angle is formed within 1.5 degrees.
As a further improvement of the utility model: the first base material and the second base material are made of copper foil.
As a still further improvement of the utility model: the thickness of the first substrate and the second substrate is 6+/-1 mu m,
the thickness of the pole piece composition of the high-capacity lithium titanate battery is 230+/-12 mu m,
the positive electrode sheet and the negative electrode sheet have an effective volumetric energy density greater than 320 watt-hours/liter.
As a still further improvement of the utility model: the positive electrode sheet and the negative electrode sheet are respectively applied to the positive electrode sheet and the negative electrode sheet by a rolling machine, the tensile force is 6.7+/-0.3 megapascals, and the gradient of the tensile horizontal angle is formed within 1.5 degrees.
A high capacity lithium titanate battery comprising:
a metal shell provided with an accommodating space therein;
the positive plate is positioned in the accommodating space and consists of a first base material and at least one positive active material coating;
the negative plate is positioned in the accommodating space and consists of a second base material and at least one negative active material coating;
at least one isolating film located in the containing space and between the positive plate and the negative plate, wherein the isolating film can separate the positive plate from the negative plate so that the positive plate and the negative plate are not in direct contact with each other;
and an electrolyte, which is a solution filled in the accommodating space and can transfer metal ion substances in the accommodating space,
wherein the product of the four of the compacted density, the coating thickness, the capacity density and the active material proportion of the positive electrode active material coating is equal to the product of the four of the compacted density, the coating thickness, the capacity density and the active material proportion of the negative electrode active material coating.
As a still further improvement of the utility model: the ratio of the coating thickness of the positive electrode active material coating layer to the coating thickness of the negative electrode active material coating layer was 5.7:10 to 6.1:10.
a high capacity lithium titanate battery comprising:
a metal shell provided with an accommodating space therein;
the positive plate is positioned in the accommodating space and consists of a first base material and at least one positive active material coating;
the negative plate is positioned in the accommodating space and consists of a second base material and at least one negative active material coating;
at least one isolating film located in the containing space and between the positive plate and the negative plate, wherein the isolating film can separate the positive plate from the negative plate so that the positive plate and the negative plate are not in direct contact with each other;
and an electrolyte, which is a solution filled in the accommodating space and can transfer metal ion substances in the accommodating space,
wherein the thickness of the positive electrode active material coating layer is 37+ -2 μm, the thickness of the negative electrode active material coating layer is 63+ -2 μm, the thickness of the separator is 9+ -1 μm, and the product of the four of the compacted density, the coating thickness, the capacity density and the active material ratio of the positive electrode active material coating layer is equal to the product of the four of the compacted density, the coating thickness, the capacity density and the active material ratio of the negative electrode active material coating layer.
Compared with the prior art, the utility model has the beneficial effects that:
the high-capacity lithium titanate battery provided by the embodiment of the utility model can improve the processes of coating, rolling, cutting and winding in battery manufacturing, is good in use of limited physical volume space, and solves the problem of battery capacity density.
Drawings
FIG. 1 is a cross-sectional view of a pole piece assembly of the present utility model;
FIG. 2 is a schematic view of the internal structure of the present utility model;
FIG. 3 is a second cross-sectional view of the pole piece assembly of the present utility model;
FIG. 4 is a schematic illustration of a pole piece roll-in fabrication in accordance with the present utility model;
FIG. 5 is a schematic diagram of the analysis of pole piece rolling mechanics, tensile and shear stress in the present utility model;
FIG. 6 is a schematic view of a pole piece roll mechanical analysis in the present utility model;
fig. 7 is a schematic view of the internal structure of a rectangular battery according to the present utility model;
fig. 8 is a schematic view of the internal structure of the soft pack battery according to the present utility model.
Detailed Description
The technical scheme of the patent is further described in detail below with reference to the specific embodiments.
Embodiments of the present patent are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary only for explaining the present patent and are not to be construed as limiting the present patent.
Referring to fig. 2-6, the present embodiment provides a high-capacity lithium titanate battery, wherein the lithium titanate battery 1 at least comprises a metal housing 2 having a receiving space 20 therein; a positive electrode sheet 3 is located in the accommodation space 20, the positive electrode sheet 3 is composed of a first substrate 32 and at least one positive electrode active material coating 31; a negative electrode sheet 4 is disposed in the accommodating space 20, the negative electrode sheet 4 is composed of a second substrate 42 and at least one negative electrode active material coating 41; at least one isolation film 5 is located in the accommodation space 20 and between the positive plate 3 and the negative plate 4, the isolation film 5 can separate the positive plate 3 and the negative plate 4 so that the two are not in direct contact with each other; and an electrolyte 6 is a solution filled in the accommodating space 20, the electrolyte 6 being capable of transferring metal ion substances in the accommodating space 20; wherein the thickness of the positive electrode active material coating layer 31 is 37.+ -.2. Mu.m, the thickness of the negative electrode active material coating layer 41 is 63.+ -.2. Mu.m, and the thickness of the separator 5 is 9.+ -.1. Mu.m.
Referring to fig. 3, in one embodiment, the positive electrode material of the present utility model is represented by lithium cobaltate, and has the chemical reaction formula:
and (3) a positive electrode:
and (3) a negative electrode:
the first substrate 32 and the second substrate 42 are made of aluminum foil, and the thickness of the first substrate 32 and the second substrate 42 is 10±1 μm, so that the pole piece composition thickness of the high-capacity lithium titanate battery is 238±12 μm, wherein the pole piece composition thickness is formed by adding one piece of the first substrate 32, two layers of positive electrode active material coatings 31, one piece of the second substrate 42, two layers of negative electrode active material coatings 41 and two pieces of isolation films 5, and the effective volume energy density of the positive electrode sheet 3 and the negative electrode sheet 4 is more than 310 watt hours/liter.
Referring to fig. 3, in one embodiment, the first substrate 32 and the second substrate 42 are made of copper foil, the thickness of the first substrate 32 and the second substrate 42 is 6±1 μm, the pole piece composition thickness of the high capacity lithium titanate battery is 230±12 μm, wherein the pole piece composition thickness is formed by adding one first substrate 32, two positive electrode active material coatings 31, one second substrate 42, two negative electrode active material coatings 41 and two separator films 5, and the effective volume energy density of the positive electrode sheet and the negative electrode sheet is 320 watt hours/liter (WH/L) or more.
Referring to fig. 3-6, in one embodiment, the first substrate 32 and the second substrate 42 are subjected to a tensile force applied by a machine during the coating and rolling of the anode and cathode materials, and the tensile force applied by the machine is found to be such that the aluminum foil is stretched, but not the reason for tearing the aluminum foil, but the lateral shearing stress generated by the tensile force exceeds the shearing stress that the aluminum foil can withstand to tear when the aluminum foil surface and the tensile force are not parallel, and the angle between the aluminum foil plane and the machine applied by the machine is controlled to be within 1.5 degrees, such that the aluminum foil plane and the machine applied by the tensile force of 6.7±0.3 megapascal (MPa) is controlled to be as thin as 10±1 μm, and the aluminum foil can be maintained without breaking.
Referring to fig. 4-6, in one embodiment, the battery pole piece coated with the active material is fed into a roller press 8 from a discharge shaft 7 end, compacted by a roller, and recovered into a roll at a receiving shaft 9 end. When the discharging shaft 7 before rolling or the collecting shaft 9 after rolling inclines, the forward stress F of stretching X Will generate lateral vertical component force F Y When shearing stress S of the branch S When the thickness is too large, the pole piece base material is torn and broken. In order to enable the pole piece to have certain flatness when in rolling, the inventor knows that the calculation mode is as follows after a plurality of practical research experiments:
vertical component force (F) Y ) =total tensile force (F) ×sin a;
shear stress (S) S )＝F Y /(total width of pole piece (w) ×thickness of assembly (t));
tension (S) N )＝F/(w×t)。
From the above, the feeding roller has a tension of at least 6+ -0.3 MPa (S N ) While the aluminum foil is subjected to shear stress (S S ) The strength was 0.18.+ -. 0.01MPa, from which it was calculated that the horizontal tilt angle of the feed roller should not exceed sin-1 (0.18/6) =1.72 degrees. When applied to an aluminum foil substrate with a thickness of 10 μm and a total width (w) of 450mm of the pole piece, the total tensile force (F) applied by the roller is calculated as follows:
F＝S N x w x t=6 MPa x 0.45m x 10 μm=27±1.5 newton (N).
From the above, in order to optimize the various qualities of the pole piece roll-in and the roller level control, the discharge shaft 7 was increased to a tension of 30.+ -. 1.5N, i.e., the total tension (F) was increased to 6.7.+ -. 0.3MPa, to ensure the shear stress (S S ) The horizontal inclination angle of the discharging shaft 7 is controlled within +/-1.5 Degrees (DEG) which is less than 0.18+/-0.01 MPa, and the calculation mode is as follows:
S N ＝F/(w×t)＝30N/(10μm×0.45m)＝6.7MPa；
a＝sin -1 (0.18/6.7)＝1.54°。
in addition, with shear stress (S S ) The higher copper foil replaces aluminum foil, the thickness of the pole piece substrate can be further reduced, the same drawing tension of 30+/-1.5N is applied to the discharging shaft 7, namely, the total drawing tension (F) born by the copper foil substrate with the total width (w) of 450mm of the pole piece is 6.7+/-0.3 MPa, the horizontal inclination angle of the feeding roller is controlled within +/-1.5 ℃, the shearing stress is ensured to be less than 0.18+/-0.01 MPa, and the thinnest copper foil with the total width (w) of 6+/-1 mu m can be used as the pole piece substrate.
The positive electrode active material coating 31 and the negative electrode active material coating 41 are adjacent to each other with the separator 5 as a boundary, and for each corresponding unit area, under the limitation of the limiting thickness of the coating, the content ratio of the two materials needs to be adjusted so that the positive electrode and the negative electrode active material can reach the most sufficient chemical reaction, as shown in fig. 2 to 3, in the third embodiment, after the inventor researches the optimal thickness ratio of the positive electrode active material coating 31 and the negative electrode active material coating 41, and carefully analyzes each influencing capacity factor through experimental results, it is known that: density a of positive electrode active material coating 31 p (g/cc (g/cm) 3 ) Thickness d of P positive electrode coating layer) p (cm)), volume density E p (mAh/g) and active substance ratio R p The product of the four (percent (%)) is equivalent to the compacted density A of the anode active material coating layer N (g/cc (g/cm) 3 ) Thickness d of negative electrode coating layer) N (cm)), volume density E N (mAh/g) and active substance ratio R N The product of four (percent (%)), namely:
A p ×d p ×E p ×R p ＝A N ×d N ×E N ×R N 。
from the above, in one embodiment, A p The value was 3.66g/cm 3 ，E p The value is 145mAh/g, R p The value is 96%, A N The value was 2.0g/cm 3 、E N The value is 160mAh/g, R N Since the value is 94%, d is calculated from the above calculation p /d N = 300.8/509.5 =59%, but not limited to, in realityIn the production process, tolerance problems are generated, so that the thickness d of the positive electrode coating and the thickness d of the negative electrode coating p Can be 59 + -2% (i.e., 5.7:10 to 6.1:10), the anode coating thickness d in the case of comparable anode and cathode capacitances N Will be greater than the thickness d of the positive electrode coating p Therefore, in the manufacturing process of the lithium titanate battery, the negative electrode coating thickness d N The problems of material adhesion and powder cutting are encountered, so that the capacitance of the lithium titanate battery is defined by the thickness d of the negative electrode coating N And (3) determining. The thickness d of the anode coating layer with the lithium titanate as the anode active material coating layer 41 with stable quality can be achieved at present by the anode coating layer production process N 63.+ -. 2 μm, and then according to the positive electrode coating thickness { (39×2+16) + (43×2+16) + (16×2) } ×1.1/1000×55×L=12979 mm 3 ；d N And the thickness d of the negative electrode coating N The ratio of (2) is 5.7:10 to 6.1:10, calculating to obtain the thickness d of the positive electrode coating p 37+ -2 μm, so that the thinnest pole piece substrate and the optimal positive electrode coating thickness d can be obtained p Thickness d of coating layer of negative electrode N With the current pole piece roll cutting process, the isolating film 5 with the thickness of 9+/-1 mu m can be used, and burrs are controlled not to pierce the isolating film 5 so as to cause short circuit between the positive pole piece 3 and the negative pole piece 4.
Furthermore, the total capacity Q of the battery pole piece is known from the product of the capacitance per unit area and the total area of the pole piece, i.e., the compacted density, the coating thickness, the capacitance density, the active material ratio, the pole piece width H (as shown in FIG. 2, i.e., the height inside the housing 2) and the pole piece lateral length L, and by way of example, the conventional cylindrical battery 18650 is provided with a metal can having an inner space for accommodating a pole piece wound into a cylinder with a diameter of 17.6mm and a height of 55mm (i.e., 5.5 cm), and a cylinder volume of 13380mm 3 However, the pole piece is wound with about 3% of the space (such as the space occupied by the reel) which is not effective in the center, so that the effective space in the metal can is 12979mm 3 The method comprises the steps of carrying out a first treatment on the surface of the The stretching volume of the pole piece before winding with the insulating piece is { (positive electrode coating thickness×2+positive electrode pole piece substrate thickness) + (negative electrode coating thickness×2+negative electrode pole piece substrate thickness) + (isolation film thickness×2) } ×H×L, and due to the material deformation generated in the thickness direction when the pole piece is wound,but cannot be completely and tightly bonded, and a 10% allowable deformation volume is required between each layer of pole pieces, the thickness (t) of the assembly of the positive and negative pole pieces and the two layers of isolating films is 228 μm by adopting the prior art, tolerance problems possibly caused during production are considered, the transverse length L of the pole pieces which can be wound in the accommodating space 20 is calculated by the following calculation formula according to the average value of the thicknesses,
{(39×2+16)+(43×2+16)+(16×2)}×1.1/1000×55×L＝12979mm 3 ；
the transverse length L of the pole piece is 941mm.
From the above, the capacity of the pole piece is calculated as the capacitance per unit area multiplied by the total area, i.e.,
positive electrode total capacity Q p ＝(A p ×d p ×E p ×R p )×H×L＝3.66×0.0039×2×145×0.96×5.5×94.1＝2057mAh；
Total negative electrode capacity Q N ＝(A N ×d N ×E N ×R N )×H×L＝2.0×0.0043×2×160×0.94×5.5×94.1＝1339mAh。
Since the effective capacity of the battery is determined by the capacity of one of the positive electrode and the negative electrode with a smaller amount of material, the positive electrode material used in the prior art is 718mAh more than the negative electrode material, i.e. 35% of the positive electrode material, which not only does not contribute to the capacity of the battery, but also occupies more ineffective space, so that the effective volumetric energy density of the battery electrode sheet is:
1339mAh×2.4V/13380mm 3 ＝240±12WH/L。
the present utility model adopts an optimized design, wherein when the first substrate 32 and the second substrate 42 are made of aluminum foil, a substrate with a thickness of 10+ -1 μm is adopted, the thickness of the positive electrode active material coating 31 is 37+ -2 μm, the thickness of the negative electrode active material coating 41 is 63+ -2 μm, the thickness of the isolating film 5 is 9+ -1 μm, the thickness of the pole piece composition is 238+ -12 μm, and considering the problem of possible derivative tolerance in production, the transverse length L of the aluminum foil pole piece windable in the space of the container is obtained by the following calculation formula by the average value of the thicknesses:
{ (37×2+10) + (63×2+10) + (9×2) } ×1.1/1000×55×poleSheet transverse length l=12979 mm 3 。
The length of the pole piece is 901mm.
Thus, the total positive electrode capacity Q p ＝(A p ×d p ×E p ×R p )×H×L＝3.66×0.0037×2×145×0.96×5.5×90.1＝1868mAh；
Total negative electrode capacity Q N ＝(A N ×d N ×E N ×R N )×H×L＝2.0×0.0063×2×160×0.94×5.5×90.1＝1878mAh。
The effective volume energy density of the battery pole piece is 1868mAh multiplied by 2.4V/13380mm 3 The effective volumetric energy density of the battery pole piece can be 335±5%wh/L, considering, but not limited to, can tolerance and internal space effectiveness issues that may be derived during production.
Compared with the prior art, the capacity ratio of the utility model is 1868/1339=1.395, the capacitance is increased by 39.5%, and the experimental result proves that the capacity of the battery applied to 18650 model can reach more than 1750mAh, and the capacitance is increased by 34.6% compared with the capacity of 1300mAh in the prior art. Furthermore, the utility model adopts thinner copper foil base material with the thickness of 6+/-1 mu m to replace aluminum foil with the thickness of 10+/-1 mu m, the thickness (t) of the assembly of the positive and negative pole pieces and the two layers of isolating films is 230+/-12 mu m, and considering the problem of possible derivative tolerance in production, the transverse length L of the windable copper foil pole piece in the space of the containing tank is calculated by the following calculation method according to the average value of the thicknesses:
{(37×2+6)+(63×2+6)+(9×2)}×1.1/1000×55×L＝12979mm 3 the method comprises the steps of carrying out a first treatment on the surface of the The transverse length L of the copper foil pole piece is 933mm.
Thus, the total positive electrode capacity Q p ＝(A p ×d p ×E p ×R p )×H×L＝3.66×0.0037×2×145×0.96×5.5×93.3＝1935mAh；
Total negative electrode capacity Q N ＝(A N ×d N ×E N ×R N )×H×L＝2.0×0.0063×2×160×0.94×5.5×93.3＝1945mAh。
The effective volume energy density of the battery pole piece is 1935mAh multiplied by 2.4V/13380mm < 3 > =347 WH/L, but the energy density is not limited to this, and can tolerance and internal space effectiveness problems can be derived during production are considered, and the effective volume energy density of the battery pole piece can also be 347+/-5% WH/L.
Therefore, the capacity ratio of the 6 μm copper foil substrate adopted by the utility model relative to the prior art is 1935/1339=1.445, and the capacitance can be increased by 44.5%. The shape of the shell 2 of the present utility model may be rectangular, as shown in fig. 7, in which the rolled positive electrode sheet 3 and negative electrode sheet 4 are separated by a separator 5, then rolled and flattened into the shell 2 to form a rectangular (prismatic) battery; in addition, as shown in fig. 8, the material of the casing 2 can be aluminum foil, and the rolled positive electrode sheet 3 and negative electrode sheet 4 are cut and stacked in the casing 2 after being separated by the separator 5, so that the positive electrode sheet 3, the negative electrode sheet 4 and the separator 5 are laminated in a sheet shape, and the casing top surface 21 and the casing bottom surface 22 of the casing 2 can cover the positive electrode sheet 3, the negative electrode sheet 4 and the separator 5 therein to form a soft package (touch) battery, so that the space in the casing 2 can be fully utilized and the ineffective space in the casing 2 can be reduced. Furthermore, the number of the positive electrode sheet 3, the negative electrode sheet 4 and the separator 5 is not limited to the number drawn in fig. 8, and the manufacturer can match the corresponding number of the positive electrode sheet 3, the negative electrode sheet 4 and the separator 5 according to the product requirement.
While the preferred embodiments of the present patent have been described in detail, the present patent is not limited to the above embodiments, and various changes may be made without departing from the spirit of the present patent within the knowledge of those skilled in the art.
Claims (9)
1. A high capacity lithium titanate battery, comprising:
a metal shell provided with an accommodating space therein;
the positive plate is positioned in the accommodating space and consists of a first base material and at least one positive active material coating;
the negative plate is positioned in the accommodating space and consists of a second base material and at least one negative active material coating;
at least one isolating film located in the containing space and between the positive plate and the negative plate, wherein the isolating film can separate the positive plate from the negative plate so that the positive plate and the negative plate are not in direct contact with each other;
and an electrolyte, which is a solution filled in the accommodating space and can transfer metal ion substances in the accommodating space;
wherein the thickness of the positive electrode active material coating layer is 37+ -2 μm, the thickness of the negative electrode active material coating layer is 63+ -2 μm, and the thickness of the separator is 9+ -1 μm.
2. The high capacity lithium titanate battery of claim 1, wherein the first substrate and the second substrate are aluminum foil.
3. The high capacity lithium titanate battery of claim 2, wherein the first substrate and the second substrate have a thickness of 10.+ -. 1 μm,
the thickness of the pole piece composition of the high-capacity lithium titanate battery is 238+/-12 mu m,
the positive electrode sheet and the negative electrode sheet have an effective volumetric energy density greater than 310 watt hours/liter.
4. A high capacity lithium titanate battery according to claim 3, wherein said positive electrode sheet and said negative electrode sheet are respectively applied with a tensile force of 6.7±0.3 megapascals by a rolling machine, and the inclination of the stretching horizontal angle of the tensile force is formed within 1.5 degrees.
5. The high capacity lithium titanate battery of claim 1, wherein the first substrate and the second substrate are copper foil.
6. The high capacity lithium titanate battery of claim 4, wherein the first substrate and the second substrate have a thickness of 6.+ -. 1. Mu.m,
the thickness of the pole piece composition of the high-capacity lithium titanate battery is 230+/-12 mu m,
the positive electrode sheet and the negative electrode sheet have an effective volumetric energy density greater than 320 watt-hours/liter.
7. A high capacity lithium titanate battery, comprising:
a metal shell provided with an accommodating space therein;
the positive plate is positioned in the accommodating space and consists of a first base material and at least one positive active material coating;
the negative plate is positioned in the accommodating space and consists of a second base material and at least one negative active material coating;
at least one isolating film located in the containing space and between the positive plate and the negative plate, wherein the isolating film can separate the positive plate from the negative plate so that the positive plate and the negative plate are not in direct contact with each other;
and an electrolyte, which is a solution filled in the accommodating space and can transfer metal ion substances in the accommodating space,
the product of the compacted density, the coating thickness, the capacity density and the active material proportion of the positive electrode active material coating is equal to the product of the compacted density, the coating thickness, the capacity density and the active material proportion of the negative electrode active material coating.
8. The high capacity lithium titanate battery of claim 7, wherein the ratio of the coating thickness of the positive electrode active material coating to the coating thickness of the negative electrode active material coating is 5.7:10 to 6.1:10.
9. a high capacity lithium titanate battery, comprising:
a metal shell provided with an accommodating space therein;
the positive plate is positioned in the accommodating space and consists of a first base material and at least one positive active material coating;
the negative plate is positioned in the accommodating space and consists of a second base material and at least one negative active material coating;
at least one isolating film located in the containing space and between the positive plate and the negative plate, wherein the isolating film can separate the positive plate from the negative plate so that the positive plate and the negative plate are not in direct contact with each other;
and an electrolyte, which is a solution filled in the accommodating space and can transfer metal ion substances in the accommodating space,
wherein the thickness of the positive electrode active material coating layer is 37+ -2 μm, the thickness of the negative electrode active material coating layer is 63+ -2 μm, the thickness of the separator is 9+ -1 μm, and the product of the four of the compacted density, the coating thickness, the capacity density and the active material ratio of the positive electrode active material coating layer is equal to the product of the four of the compacted density, the coating thickness, the capacity density and the active material ratio of the negative electrode active material coating layer.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| TW11030030 | 2021-08-13 | ||
| TW110130030A TWI775568B (en) | 2021-08-13 | 2021-08-13 | High-capacity lithium titanate battery |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN219513161U true CN219513161U (en) | 2023-08-11 |
Family
ID=83807297
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202222126150.XU Active CN219513161U (en) | 2021-08-13 | 2022-08-12 | High-capacity lithium titanate battery |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN219513161U (en) |
| TW (1) | TWI775568B (en) |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI741800B (en) * | 2019-09-18 | 2021-10-01 | 財團法人工業技術研究院 | Fast charging lithium battery |
| CN111613839A (en) * | 2020-06-05 | 2020-09-01 | 惠州市太能锂电有限公司 | Novel ultrathin battery and preparation process thereof |
-
2021
- 2021-08-13 TW TW110130030A patent/TWI775568B/en active
-
2022
- 2022-08-12 CN CN202222126150.XU patent/CN219513161U/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| TW202308211A (en) | 2023-02-16 |
| TWI775568B (en) | 2022-08-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US20220302426A1 (en) | Finely deposited lithium metal powder | |
| CN111969214B (en) | Positive plate with special-shaped structure and lithium ion battery comprising positive plate | |
| US6881514B2 (en) | Stacked electrochemical cell | |
| US9209478B2 (en) | Elongated mandrel for a winding device | |
| TW416159B (en) | Nonaqueous-electrolyte secondary battery | |
| JP5255538B2 (en) | Unit cell for secondary battery having conductive sheet layer and lithium ion secondary battery using the same | |
| KR20080057223A (en) | Battery | |
| US11296325B2 (en) | Electrode for secondary battery including electrode protecting layer | |
| CN112234212A (en) | Positive pole piece and lithium ion battery comprising same | |
| CN113506878A (en) | Composite conductive current collector, electrode plate and lithium ion battery | |
| CN115461909A (en) | Electrochemical device and electronic device comprising same | |
| CN219513161U (en) | High-capacity lithium titanate battery | |
| CN112234247A (en) | Lithium ion battery | |
| JP2000021452A (en) | Nonaqueous electrolyte secondary battery | |
| CN116646621A (en) | Detachable battery cell negative electrode exogenous lithium supplementing method | |
| CN116344741A (en) | Positive electrode sheet, secondary battery, and electricity consumption device | |
| CN114122326B (en) | Lithium supplementing method of lithium ion battery | |
| EP4020648A1 (en) | Electrochemical device and electronic device including same | |
| CN115332725B (en) | Diaphragm and battery | |
| US20240186493A1 (en) | Manufacturing of an electrode laminate with a treated carrier foil | |
| CN209929389U (en) | Soft package lithium ion battery with compressible diaphragm | |
| KR100647567B1 (en) | Cylindrical type lithium ion polymer battery and method of producing same | |
| CN116053408A (en) | Positive pole piece, energy storage device and electric equipment | |
| EP4055647A1 (en) | Methods for improving lithium cell performance comprising carbon nanotube (cnt)-metal composites | |
| CN115117352A (en) | Negative plate and battery |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |