CN111987286B - Negative plate and lithium ion battery comprising same - Google Patents
Negative plate and lithium ion battery comprising same Download PDFInfo
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- CN111987286B CN111987286B CN202010962699.5A CN202010962699A CN111987286B CN 111987286 B CN111987286 B CN 111987286B CN 202010962699 A CN202010962699 A CN 202010962699A CN 111987286 B CN111987286 B CN 111987286B
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- H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
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Abstract
The invention provides a negative plate and a lithium ion battery comprising the same; the negative plate is prepared by respectively using graphite with different interlayer spacings at the position close to the negative pole tab and other regions, wherein the interlayer spacing of the first graphite is d1, and the interlayer spacing of the second graphite is d 2; and d1-d2 is less than 0nm and less than or equal to 0.0002 nm. Within a certain range, the larger the graphite layer spacing is, the more easily lithium ions can be inserted and extracted. Graphite with relatively large interlayer spacing is coated at a pole lug of the negative electrode, so that the lithium precipitation condition of the negative electrode is improved, and the aim of improving the cycling stability is fulfilled.
Description
Technical Field
The invention belongs to the technical field of lithium ion batteries, and particularly relates to a negative plate and a lithium ion battery comprising the same.
Background
With the advent of the electronic age, mobile power sources have been applied to various aspects of life, and at present, on the basis of meeting energy density, the need of the market is met by configuring a lithium ion battery with efficient charging capability. However, in the circulation process of the lithium ion battery with the conventional winding structure, particularly during charging, the current density of the negative plate close to the tab is high, and lithium is easy to precipitate, so that the performance of the lithium ion battery is affected.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention provides the negative plate and the lithium ion battery comprising the same. The research shows that when the lithium ion battery is charged, the more the current density of the negative electrode plate is close to the position of the pole lug is, the more lithium is easy to be separated. The negative plate is provided to improve the lithium precipitation problem of the negative plate.
The purpose of the invention is realized by the following technical scheme:
the negative plate comprises a negative current collector, wherein a blank foil area, an A coating area and a B coating area are arranged on the surface of the negative current collector from one end of the negative current collector along the length direction of the negative current collector, and the A coating area is closer to the blank foil area than the B coating area;
the empty foil area is provided with a negative electrode tab;
the A coating region includes a first negative electrode active material layer coated on a surface of a negative electrode current collector; the first anode active material layer includes a first anode active material selected from a first graphite having an interlayer distance d 1;
the B coating region includes a second negative electrode active material layer coated on a surface of the negative electrode current collector; the second anode active material layer includes a second anode active material selected from a second graphite having an interlayer distance d 2; and d1-d2 is less than 0nm and less than or equal to 0.0002 nm.
According to the present invention, the a coating region includes a first coating region, a second coating region, and a fourth coating region, and the B coating region includes a third coating region and a fifth coating region;
the first coating area and the hollow foil area are oppositely arranged along the two side surfaces of the negative electrode current collector; the second coating area and the fourth coating area are oppositely arranged along the two side surfaces of the negative current collector; the third coating area and the fifth coating area are oppositely arranged along two side surfaces of the negative electrode current collector.
Illustratively, the negative plate comprises a negative current collector, wherein a first surface of the negative current collector is provided with a hollow foil area, a first coating area, a second coating area and a third coating area in sequence from one end of the negative current collector and along the length direction of the negative current collector, and a second surface of the negative current collector opposite to the first surface is provided with a fourth coating area opposite to the second coating area and a fifth coating area opposite to the third coating area in sequence;
the empty foil area is provided with a negative electrode tab;
the first, second, and fourth coating regions include a first negative active material layer coated on a surface of a negative current collector; the first anode active material layer includes a first anode active material selected from a first graphite having an interlayer distance d 1;
the third and fifth coating regions include a second anode active material layer coated on a surface of the anode current collector; the second anode active material layer includes a second anode active material selected from a second graphite having an interlayer distance d 2; and d1-d2 is less than 0nm and less than or equal to 0.0002 nm.
According to the invention, the arrangement edge of the negative pole tab is vertical to the length direction of the negative pole current collector.
In the invention, the fourth coating area opposite to the second coating area (or the second coating area and the fourth coating area are oppositely arranged along two side surfaces of the negative current collector) means that the second coating area and the fourth coating area are symmetrically arranged by taking the negative current collector as a symmetry axis; the fifth coating area opposite to the third coating area (or the third coating area and the fifth coating area are oppositely arranged along two side surfaces of the negative electrode current collector) means that the third coating area and the fifth coating area are symmetrically arranged by taking the negative electrode current collector as a symmetry axis.
In the present invention, the first coating region is also referred to as a single-side coating region, and means that an active material paste is coated on one of both side surfaces of the negative electrode current collector, and the active material paste is not coated on the other side.
In the present invention, the second coating region, the third coating region, the fourth coating region and the fifth coating region are also referred to as double-sided coating regions, and refer to coating the symmetrically arranged second coating region and fourth coating region, and the symmetrically arranged third coating region and fifth coating region on the two side surfaces of the negative electrode current collector.
In the invention, the first coating area, the second coating area and the fourth coating area are sequentially connected on the first surface of the negative current collector; the second coating region and the fifth coating region are sequentially connected on the second surface of the negative electrode current collector.
According to the invention, the interlayer spacing d1 of the first graphite is 0.3350-0.3362 nm; the interlayer spacing d2 of the second graphite is 0.3348-0.3360 nm.
In the invention, the interlayer spacing is calculated by obtaining the angle of the graphite (002) diffraction peak through XRD test and then by Bragg equation 2dsin theta ═ lambda.
According to the invention, the particle size D of the first graphite1 50Is 5 μm<D1 50<12 μm, specific surface area of 0.8-2.0m2/g。
According to the invention, the particle diameter D of the second graphite2 50Is 8 μm<D2 50<15 μm, specific surface area of 0.5-1.5m2/g。
According to the invention, the length of the first coating area along the length direction of the negative electrode current collector is L3, the L3 is 50-200mm, and exemplarily, L3 is 114mm taking 386283 as an example.
According to the invention, along the length direction of the negative electrode current collector, the length of the second coating area on one side of the lug arranging edge is L1, and the length of the second coating area on the other side opposite to the lug arranging edge is L2, wherein L1 is more than or equal to L2.
Illustratively, the L1 is 25-100 mm; also illustratively, taking model 386283 as an example, L1 is 57 mm.
Illustratively, the L2 is 12.5-50 mm; also illustratively, taking model 386283 as an example, L2 is 28.5 mm.
Exemplarily, L1 ═ 0.5 × L3; l2 ═ 0.5 × L1.
Illustratively, L1-L2 is 28.5 mm.
According to the invention, along the length direction of the negative electrode current collector, the length of the fourth coating area on one side of the lug arranging edge is L4, and the length of the fourth coating area on the other side opposite to the lug arranging edge is L5, wherein L4 is more than or equal to L5.
Illustratively, the L4 is 25-100 mm; also illustratively, taking model 386283 as an example, L4 is 57 mm.
Illustratively, the L5 is 12.5-50 mm; also illustratively, taking model 386283 as an example, L5 is 28.5 mm.
Illustratively, L4-L5 is 28.5 mm.
Exemplarily, L4 ═ L1 and L5 ═ L2.
According to the invention, the junction of the second and third coated regions may be a straight line, a curved line (wavy line, circular arc, etc.), a stepped or profiled structure.
According to the invention, the junction of the fourth and fifth coating regions may be a straight line, a curved line (wavy line, circular arc, etc.), a step or a profiled structure.
According to the present invention, the first negative electrode active material layer further includes a first conductive agent, a first dispersant, and a first binder.
According to the present invention, the second anode active material layer further includes a second conductive agent, a second dispersant, and a second binder.
According to the invention, the first negative electrode active material layer comprises the following components in percentage by mass:
70-98.5 wt% of first negative electrode active material, 0.5-10 wt% of first conductive agent, 0.5-10 wt% of first binder and 0.5-10 wt% of first dispersing agent.
Preferably, the first negative electrode active material layer comprises the following components in percentage by mass:
85-97 wt% of first negative electrode active material, 1-5 wt% of first conductive agent, 1-5 wt% of first binder and 1-5 wt% of first dispersing agent.
According to the invention, the second anode active material layer comprises the following components in percentage by mass:
70-98.5 wt% of second negative electrode active material, 0.5-10 wt% of second conductive agent, 0.5-10 wt% of second binder and 0.5-10 wt% of second dispersing agent.
Preferably, the second anode active material layer comprises the following components in percentage by mass:
85-97 wt% of second negative electrode active material, 1-5 wt% of second conductive agent, 1-5 wt% of second binder and 1-5 wt% of second dispersing agent.
Wherein the first conductive agent and the second conductive agent are the same or different and are independently selected from at least one of conductive carbon black, acetylene black, Ketjen black, conductive graphite, conductive carbon fiber, carbon nanotube, metal powder and carbon fiber.
Wherein the first binder and the second binder are the same or different and are independently selected from at least one of styrene-butadiene latex, polytetrafluoroethylene and polyethylene oxide.
Wherein the first dispersing agent and the second dispersing agent are the same or different, and at least one of sodium carboxymethyl cellulose and lithium carboxymethyl cellulose is selected independently from each other.
The invention also provides a preparation method of the negative plate, which comprises the following steps:
1) preparing a slurry for forming a first negative electrode active material layer and a slurry for forming a second negative electrode active material layer, respectively;
2) and coating the slurry for forming the first negative electrode active material layer and the slurry for forming the second negative electrode active material layer on the surface of a negative electrode current collector by using a double-layer coating machine to prepare the negative electrode sheet.
According to the present invention, in step 1), the solid contents of the slurry for forming the first anode active material layer and the slurry for forming the second anode active material layer are 40 wt% to 45 wt%.
The invention also provides a lithium ion battery which comprises the negative plate.
The invention has the beneficial effects that:
the invention provides a negative plate and a lithium ion battery comprising the same; the negative electrode sheet uses graphite having different interlayer distances in a region near the negative electrode tab (e.g., a coated region) and a region far from the negative electrode tab (e.g., B coated region), respectively. Within a certain range, the larger the graphite layer spacing is, the more easily lithium ions can be inserted and extracted. Graphite with relatively large interlayer spacing is coated in a region (such as coating region A) close to a cathode lug, so that the lithium precipitation condition of the cathode is improved, and the aim of improving the cycle stability is fulfilled. According to the application, the single-side coating area is further arranged in the area (such as the coating area A) close to the pole lug of the negative electrode, so that the coating amount of graphite with large interlayer spacing is further increased, the lithium ions are ensured to be embedded and separated, and the problem of lithium precipitation of the negative electrode is further improved.
Drawings
Fig. 1 is a schematic view of the structure of the first surface (C-plane, surface of active material coated longer plane) of the negative electrode sheet according to the present invention.
Fig. 2 is a schematic view of the structure of the second surface (D-side, surface of active material-coated shorter side) of the negative electrode sheet according to the present invention.
Fig. 3 is a bottom longitudinal structure schematic diagram of the negative electrode sheet of the present invention.
Wherein, the following steps: a first coated region; secondly, the step of: a second coated region; ③: a third coated region; fourthly, the method comprises the following steps: a fourth coated region; fifthly: a fifth coated region; 1 is a negative pole tab; and 2 is a negative electrode current collector.
Detailed Description
The present invention will be described in further detail with reference to specific examples. It is to be understood that the following examples are only illustrative and explanatory of the present invention and should not be construed as limiting the scope of the present invention. All the technologies realized based on the above-mentioned contents of the present invention are covered in the protection scope of the present invention.
The negative electrode sheet prepared in the following example was for an 386283-type battery, in which the distance of the negative electrode tab disposed in the tab region from the first coating region was 35 ± 0.5mm, the total length of the second and third coating regions was 830 ± 2mm, the length of the first coating region was 114 ± 2mm, and the width of the current collector was 77.5 ± 0.1 mm.
The experimental methods used in the following examples are all conventional methods unless otherwise specified; reagents, materials and the like used in the following examples are commercially available unless otherwise specified.
In the description of the present invention, it should be noted that the terms "first", "second", "third", "fourth", "fifth", etc. are used for descriptive purposes only and are not intended to indicate or imply relative importance.
Example 1
(1) Preparation of negative plate
The negative plate comprises a negative current collector, the negative current collector is arranged from one end of the negative current collector along the length direction of the negative current collector, the first surface of the negative electrode current collector is provided with a hollow foil area, a first coating area, a second coating area and a third coating area in sequence, a fourth coating region opposite to the second coating region and a fifth coating region opposite to the third coating region are sequentially disposed on a second surface of the negative electrode current collector opposite to the first surface, specifically, as shown in fig. 1, one side of the negative current collector coated with the first coating area, the second coating area and the third coating area is defined as a C surface (a first surface), and one side of the negative current collector coated with the fourth coating area and the fifth coating area is defined as a D surface (a second surface);
the first, second, and fourth coating regions include a first negative active material layer coated on a surface of a negative current collector; the first anode active material layer includes a first anode active material selected from graphite 1; the third and fifth coating regions include a second anode active material layer coated on a surface of the anode current collector; the second anode active material layer includes a second anode active material selected from graphite 2;
TABLE 1 interlayer spacing of graphite used in examples and comparative examples
| d002(nm) | | |
| Graphite | ||
| 1 | 0.335900 | 26.51388 |
| |
0.335790 | 26.52272 |
| |
0.335997 | 26.50608 |
The negative plate is prepared specifically as follows:
uniformly dispersing a mixture I consisting of 96.9 wt% of graphite 1, 0.5 wt% of a conductive agent (carbon black), 1.3 wt% of a binder (SBR) and 1.3 wt% of a dispersant (CMC) in deionized water to prepare negative electrode slurry 1;
uniformly dispersing a mixture I consisting of 96.9 wt% of graphite 2, 0.5 wt% of a conductive agent (carbon black), 1.3 wt% of a binder (SBR) and 1.3 wt% of a dispersant (CMC) in deionized water to prepare negative electrode slurry 2;
as shown in fig. 1, the coating is performed on the surface C and the surface D of the negative electrode current collector, and the specific coating process is as follows:
and coating the negative electrode slurry 1 on a first coating area and a second coating area close to a negative electrode lug on the C surface of the negative electrode current collector, and coating the negative electrode slurry 2 on a third coating area far away from the negative electrode lug.
Along the length direction of the negative current collector, the length L3 of the first coating area is 114mm, the length L1 of the second coating area on one side of the tab setting edge is 57mm, and the length L2 of the second coating area on the other side opposite to the tab setting edge is 28.5 mm.
And coating the negative electrode slurry 1 on a fourth coating area close to the negative electrode lug and coating the negative electrode slurry 2 on a fifth coating area far away from the negative electrode lug on the surface D of the negative electrode current collector.
And along the length direction of the negative electrode current collector, the length L4 of the fourth coating area on one side of the lug setting edge is 57mm, and the length L5 of the fifth coating area on the other side opposite to the lug setting edge is 28.5 mm.
(2) Preparation of positive plate
Lithium cobaltate is taken as a positive electrode active material, then the positive electrode active material, a conductive agent (carbon black) and a binder (polyvinylidene fluoride) are added into a stirring tank according to the mass ratio of 97.2:1.5:1.3, an NMP solvent is added, the mixture is fully stirred and passes through a 200-mesh screen to be prepared into positive electrode slurry, the solid content of the positive electrode slurry is 70-75 wt%, then the slurry is coated on an aluminum foil by utilizing a coating machine, and the aluminum foil is dried at the temperature of 120 ℃, so that a positive electrode sheet is obtained.
(3) Preparation of the Battery
And rolling and cutting the negative plate, and then matching and winding the negative plate with the positive plate → packaging → baking injection → formation → secondary sealing → sorting to obtain the lithium ion battery.
Comparative example 1
And coating the negative electrode slurry 1 on a first coating area and a second coating area close to a negative electrode lug on the C surface of the negative electrode current collector, and coating the negative electrode slurry 2 on a third coating area far away from the negative electrode lug. And coating the negative electrode slurry 1 on a fourth coating area close to the negative electrode lug and coating the negative electrode slurry 2 on a fifth coating area far away from the negative electrode lug on the surface D of the negative electrode current collector.
The present comparative example is different from example 1 in that the length L3 of the first coating region is 114mm, the length L1 of the second coating region is 28.5mm at one side of the tab disposition edge, and the length L2 of the second coating region is 57mm at the other side opposite to the tab disposition edge, in the length direction of the anode current collector.
And along the length direction of the negative electrode current collector, the length L4 of the fourth coating area on one side of the lug setting edge is 28.5mm, and the length L5 of the fifth coating area on the other side opposite to the lug setting edge is 57 mm.
Comparative example 2
And coating the negative electrode slurry 1 on a first coating area and a second coating area close to a negative electrode lug on the C surface of the negative electrode current collector, and coating the negative electrode slurry 2 on a third coating area far away from the negative electrode lug. And coating the negative electrode slurry 1 on a fourth coating area close to the negative electrode lug and coating the negative electrode slurry 2 on a fifth coating area far away from the negative electrode lug on the surface D of the negative electrode current collector.
The present comparative example is different from example 1 in that the length L3 of the first coating region is 114mm, the length L1 of the second coating region is 57mm at one side of the tab disposition edge, and the length L2 of the second coating region is 114mm at the other side opposite to the tab disposition edge, in the length direction of the negative electrode collector.
And along the length direction of the negative electrode current collector, the length L4 of the fourth coating area on one side of the lug setting edge is 57mm, and the length L5 of the fifth coating area on the other side opposite to the lug setting edge is 114 mm.
Comparative example 3
Comparative example 3 is different from example 1 in that coating was performed on the C-side and D-side of the negative electrode current collector and only the negative electrode slurry 2 was coated.
Comparative example 4
Uniformly dispersing a mixture II consisting of 96.9 wt% of graphite 3, 0.5 wt% of conductive agent (carbon black), 1.3 wt% of binder (SBR) and 1.3 wt% of dispersant (CMC) in deionized water to prepare negative electrode slurry 3;
comparative example 4 is different from example 1 in that the negative electrode slurry 1 coated on the C-side and D-side of the negative electrode current collector was changed to the negative electrode slurry 3, and the others were not changed.
And (3) carrying out normal-temperature cycle test on the battery by adopting a conventional method: and (3) circulating 100 times and 500 times at 25 ℃ and 3C/0.7C, then dissecting, and observing whether the negative plate separates lithium. The testing method comprises the steps of charging the lithium ion battery to full charge at a rate of 3C at 25 ℃, then charging at constant voltage, and stopping current at 0.05C. After the charging, the battery is discharged to 3V at 0.7C rate, and the cut-off current is 0.05C. The test results are shown in table 2.
Table 2 lithium ion battery performance test results of examples and comparative examples
As can be seen from table 2, when 2 kinds of graphite having a large difference in interlayer distance (> 0.0002nm) were used for coating, it was found that the energy density of the prepared cell was significantly reduced, as compared with example 1 and comparative example 4. When the structural design of the negative electrode sheet is that L1 is less than L2, the amount of the graphite 1 needs to be increased to achieve the capacity retention rate equivalent to that of the negative electrode sheet in example 1, but the energy density of the prepared battery cell is reduced; if the amount of graphite 1 is not changed, that is, the energy density of the prepared battery core is not different from that of example 1, the capacity retention rate of the battery is obviously reduced compared with that of example 1, and a slight lithium precipitation phenomenon also occurs. When the cells prepared by comparing example 1 with comparative example 3 are coated with graphite having the same interlayer spacing (same type of graphite), although the energy density of the prepared cells is high, the capacity retention rate of the prepared cells is remarkably reduced, and a slight lithium precipitation phenomenon occurs after 100 cycles, which greatly affects the cycle performance.
The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiment. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (16)
1. A negative plate comprises a negative current collector, wherein a blank foil area, an A coating area and a B coating area are arranged on the surface of the negative current collector from one end of the negative current collector along the length direction of the negative current collector; and the a-coated area is closer to the empty foil area than the B-coated area;
the empty foil area is provided with a negative electrode tab;
the A coating region includes a first negative electrode active material layer coated on a surface of a negative electrode current collector; the first anode active material layer includes a first anode active material selected from a first graphite having an interlayer distance d 1;
the B coating region includes a second negative electrode active material layer coated on a surface of the negative electrode current collector; the second anode active material layer includes a second anode active material selected from a second graphite having an interlayer distance d 2; and d1-d2 is less than 0nm and less than or equal to 0.0002 nm.
2. The negative electrode sheet of claim 1, wherein the a-coated region includes a first coated region, a second coated region, and a fourth coated region, and the B-coated region includes a third coated region and a fifth coated region;
the first coating area and the hollow foil area are oppositely arranged along the two side surfaces of the negative electrode current collector; the second coating area and the fourth coating area are oppositely arranged along the two side surfaces of the negative current collector; the third coating area and the fifth coating area are oppositely arranged along two side surfaces of the negative electrode current collector.
3. The negative electrode sheet according to claim 2, wherein the negative electrode sheet comprises a negative electrode current collector, and a first surface of the negative electrode current collector is provided with a blank foil area, a first coating area, a second coating area and a third coating area in sequence from one end of the negative electrode current collector and along the length direction of the negative electrode current collector, and a second surface of the negative electrode current collector opposite to the first surface is provided with a fourth coating area opposite to the second coating area and a fifth coating area opposite to the third coating area in sequence.
4. The negative electrode sheet according to claim 2, wherein the first, second and fourth coated regions are connected in sequence on the first surface of the negative electrode current collector; the second coating region and the fifth coating region are sequentially connected on the second surface of the negative electrode current collector.
5. Negative electrode sheet according to any one of claims 1 to 4, wherein the first graphite has an interlayer spacing d1 of 0.3350-0.3362 nm; the interlayer spacing d2 of the second graphite is 0.3348-0.3360 nm.
6. The negative electrode sheet according to any one of claims 1 to 4, wherein the particle diameter D of the first graphite1 50Is 5 μm<D1 50<12 μm, specific surface area of 0.8-2.0m2(ii)/g; and/or the presence of a gas in the gas,
the particle diameter D of the second graphite2 50Is 8 μm<D2 50<15 μm, specific surface area of 0.5-1.5m2/g。
7. The negative electrode sheet according to any one of claims 2 to 4, wherein the length of the first coating region is L3 and the L3 is 50 to 200mm in the length direction of the negative electrode current collector.
8. The negative electrode sheet according to any one of claims 2 to 4, wherein the length of the second coating region on one side of the tab welding disposition edge is L1 and the length of the second coating region on the other side opposite to the tab welding disposition edge is L2, wherein L1 ≧ L2.
9. The negative electrode sheet of claim 8, wherein said L1 is 25-100 mm; and/or the L2 is 12.5-50 mm.
10. The negative electrode sheet according to any one of claims 2 to 4, wherein the length of the fourth coating region on one side of the tab disposing edge is L4 and the length of the fourth coating region on the other side opposite to the tab disposing edge is L5, wherein L4 ≧ L5.
11. The negative electrode sheet according to claim 8, wherein the length of the fourth coated region on one side of the tab disposition edge is L4 and the length of the fourth coated region on the other side opposite to the tab disposition edge is L5, wherein L4 is L5.
12. The negative electrode sheet as claimed in claim 10, wherein the fourth coated region has a length L4 of 25-100mm on the tab disposing edge side; and/or the presence of a gas in the gas,
the length L5 of the fourth coated region on the other side opposite to the tab setting edge is 12.5 to 50 mm.
13. The negative electrode sheet as claimed in claim 11, wherein the fourth coated region has a length L4 of 25-100mm on the tab disposing edge side; and/or the presence of a gas in the gas,
the length L5 of the fourth coated region on the other side opposite to the tab setting edge is 12.5 to 50 mm.
14. The negative electrode sheet of claim 13, wherein L4-L1 and L5-L2.
15. Negative electrode sheet according to any of claims 2 to 4, wherein the junction of the second and third coated regions is a straight line, a curve, a step or a profile; and/or the presence of a gas in the gas,
the joint of the fourth coating area and the fifth coating area is in a straight line, curve, step-shaped or special-shaped structure.
16. A lithium ion battery comprising the negative electrode sheet of any one of claims 1 to 15.
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| JP2017062992A (en) * | 2015-09-25 | 2017-03-30 | 日立化成株式会社 | Negative electrode material for lithium ion secondary battery, negative electrode material slurry for lithium ion secondary battery, negative electrode for lithium ion secondary battery, and lithium ion secondary battery |
| CN109638212A (en) * | 2018-11-20 | 2019-04-16 | 东莞锂威能源科技有限公司 | A kind of high magnification fast charge lithium ion battery |
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| WO2019050094A1 (en) * | 2017-09-05 | 2019-03-14 | 주식회사 아이에프엠 | Lithium titanate oxide for lithium secondary battery anode active material and manufacturing method therefor |
| CN111092255B (en) * | 2018-10-23 | 2021-11-09 | 深圳新宙邦科技股份有限公司 | Lithium ion battery |
| CN111129503B (en) * | 2018-10-31 | 2021-06-15 | 宁德时代新能源科技股份有限公司 | Negative pole piece and secondary battery |
| CN210379299U (en) * | 2019-08-02 | 2020-04-21 | 江西迪比科股份有限公司 | Overcharge-preventing battery of high-capacity ternary secondary battery |
| CN111403705A (en) * | 2020-03-19 | 2020-07-10 | 风帆有限责任公司 | Negative electrode material of high-power lithium battery, preparation method and lithium battery |
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| JP2017062992A (en) * | 2015-09-25 | 2017-03-30 | 日立化成株式会社 | Negative electrode material for lithium ion secondary battery, negative electrode material slurry for lithium ion secondary battery, negative electrode for lithium ion secondary battery, and lithium ion secondary battery |
| CN109638212A (en) * | 2018-11-20 | 2019-04-16 | 东莞锂威能源科技有限公司 | A kind of high magnification fast charge lithium ion battery |
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