WO2022179107A1 - 一种具有曲面锂片负极的锂金属电池 - Google Patents

一种具有曲面锂片负极的锂金属电池 Download PDF

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Publication number
WO2022179107A1
WO2022179107A1 PCT/CN2021/122172 CN2021122172W WO2022179107A1 WO 2022179107 A1 WO2022179107 A1 WO 2022179107A1 CN 2021122172 W CN2021122172 W CN 2021122172W WO 2022179107 A1 WO2022179107 A1 WO 2022179107A1
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Prior art keywords
curved
battery
lithium
negative electrode
sheet
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PCT/CN2021/122172
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English (en)
French (fr)
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袁伟
王淳
陈明月
高欣竹
王程
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华南理工大学
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Priority to JP2023513411A priority Critical patent/JP2023538778A/ja
Publication of WO2022179107A1 publication Critical patent/WO2022179107A1/zh

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/134—Electrodes based on metals, Si or alloys
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/058—Construction or manufacture
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M2004/025—Electrodes composed of, or comprising, active material with shapes other than plane or cylindrical
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/027—Negative electrodes
    • 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
    • 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
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Definitions

  • the invention relates to the technical field of lithium batteries, in particular to a lithium metal battery with a curved lithium sheet negative electrode.
  • lithium metal batteries have been widely used in various fields.
  • lithium metal batteries in the prior art have the following technical problems: lithium metal powder or dendrites are prone to occur, which in turn causes low coulombic efficiency and reduced battery capacity of lithium batteries, and reduces cycle efficiency and service life.
  • the purpose of the present invention is to provide a lithium metal battery with a curved lithium sheet negative electrode, which can suppress the growth of lithium dendrites, prevent the powdering of the negative electrode lithium metal, and improve the cycle stability of the lithium battery. Extended service life.
  • a lithium metal battery with a curved lithium sheet negative electrode comprising a battery case, a diaphragm is arranged in the battery case, two ends of the diaphragm are respectively connected to the middle of the battery case, and a first cavity is arranged between the diaphragm and one end of the battery case, A second cavity is arranged between the diaphragm and the other end of the battery case, an electrode sheet is arranged in the first cavity, and the electrode sheet is in contact with one end of the battery case, a battery negative electrode is arranged in the second cavity, and both ends of the battery negative electrode are arranged Abutting against the diaphragm and the other end of the battery case respectively, the negative electrode of the battery is made of a curved lithium sheet, the first cavity and the second cavity are filled with electrolyte, and the electrode sheet and the negative electrode of the battery are respectively soaked in the electrolyte.
  • an elastic device is provided on the negative electrode of the battery, and both ends of the elastic device are respectively abutted against the negative electrode of the battery and the other end of the battery case.
  • the elastic device is an elastic sheet.
  • a gasket is arranged between the elastic sheet and the negative electrode of the battery, and both ends of the gasket are respectively abutted against the elastic sheet and the negative electrode of the battery.
  • the electrode sheet is made of curved lithium sheet.
  • the curved lithium sheet includes several concave parts, and the height of the concave parts is less than 10 mm.
  • the preparation method of the curved lithium sheet is to perform a curved surface structure on the flat lithium sheet by imprinting and rolling.
  • the preparation method of the curved lithium sheet includes the following steps:
  • the curved mold is manufactured by 3D printing method.
  • the 3D printing of the curved mold includes the following steps,
  • the present invention has the following advantages:
  • the curved lithium sheet itself has a certain curvature, in the process of lithium nucleation, the area of the SEI film caused by the raised lithium core will become smaller when the SEI film is lifted, and it is not easy to burst, thus effectively preventing the rupture of the SEI film and the curved lithium sheet.
  • the curved surface effectively extends the area of the negative electrode SEI film of the battery, effectively reduces the puncture of the SEI film caused by dendrite growth and volume increase, and the SEI film is not easy to break.
  • the contact between the curved lithium sheet and the separator is in line contact, the concave area of the curved lithium sheet becomes an area where the electrolyte is effectively stored.
  • the curved lithium sheet increases the effective surface area of the battery negative electrode, enhances the electrochemical reaction kinetics, and increases the lithium ion migration path, which is conducive to maintaining the battery capacity and cycle efficiency of the lithium metal battery and prolonging the service life.
  • FIG. 1 is a schematic diagram of the assembly of the lithium iron phosphate half-cell in Example 1.
  • FIG. 1 is a schematic diagram of the assembly of the lithium iron phosphate half-cell in Example 1.
  • Example 2 is a graph showing the discharge specific capacity and coulombic efficiency of the lithium iron phosphate half-cells using curved lithium sheets and flat lithium sheets as the negative electrode of the battery in Example 1 under the condition of 2C.
  • Example 3 is a graph showing the cycle voltage of a lithium symmetric battery using a curved lithium sheet and a flat lithium sheet as the electrode sheet and the negative electrode of the battery in Example 2.
  • 1-electrode sheet 2-battery shell, 3-gasket, 4-shrapnel, 5-battery negative electrode, 6-diaphragm, 7-electrolyte.
  • a lithium metal battery with a curved lithium sheet negative electrode includes a battery case 2, and a separator 6 is arranged in the battery case 2. The two ends of the separator 6 are respectively connected to the middle of the battery case 2.
  • a first cavity is provided between one end of the battery case 2
  • a second cavity is provided between the diaphragm 6 and the other end of the battery case 2
  • an electrode sheet 1 is arranged in the first cavity, and the electrode sheet 1 is in contact with the battery
  • the second cavity is provided with a battery negative electrode 5
  • the two ends of the battery negative electrode 5 are respectively in contact with the diaphragm 6 and the other end of the battery shell 2
  • the battery negative electrode 5 is made of a curved lithium sheet, the first cavity and the The second cavity is filled with the electrolyte 7 , and the electrode sheet 1 and the negative electrode 5 of the battery are respectively soaked in the electrolyte 7 .
  • lithium iron phosphate is used as the active material of the electrode sheet 1 (area density is 14.5 mg/cm 2 ).
  • the negative electrode 5 of the battery made of the curved lithium sheet begins to delithium, and the lithium ions enter the electrolyte 7 through the diaphragm 6, and then contact the active material on the electrode sheet 1, and a lithium intercalation reaction occurs; , the electrons enter from the other end of the battery case 2 to one end of the battery case 2; since the electrode sheet 1 is in contact with one end of the battery case 2, the electrons then enter the active material of the electrode sheet 1 to neutralize the charge with lithium ions , to complete the discharge process of the lithium metal battery.
  • lithium metal battery When the lithium metal battery is charged, lithium ions are first detached from the active material on the electrode sheet 1, enter the electrolyte 7, and then contact the curved lithium sheet through the diaphragm 6; electrons are transferred from the active material on the electrode sheet 1, successively.
  • the charging process is completed through charge balance between one end of the battery case 2 and the other end of the battery case 2 and the lithium ions on the curved lithium sheet.
  • the improvement of the stability of lithium metal anode is a key research direction to ensure the development of lithium battery technology.
  • the applicant has uniquely found that the main reason for the rapid growth of lithium dendrites and the reduced performance of the lithium metal battery in the prior art lithium metal battery is that a flat lithium sheet is used as the negative electrode 5 of the battery.
  • the solid-state electrolyte interface film (SEI film) formed in traditional liquid electrolytes is not stable, which is likely to reduce battery capacity, cycle efficiency, and life.
  • SEI film solid-state electrolyte interface film
  • the negative electrode of the flat lithium sheet loses electrons, and lithium ions are nucleated on the surface of the negative electrode of the flat lithium sheet, and the SEI film on the flat lithium sheet is both flat.
  • the SEI film is burst, so that cracks are generated on the SEI film, and lithium ions continue to deposit on the cracks, resulting in the rapid growth of lithium dendrites.
  • the present invention creatively uses a curved lithium sheet as the negative electrode 5 of the battery. Since the curved lithium sheet itself has a certain curvature, during the lithium nucleation process, the raised lithium core pushes up the SEI film. The change becomes smaller and it is not easy to burst, thus effectively preventing the rupture of the SEI film.
  • the curved surface of the curved lithium sheet effectively extends the area of the SEI film of the negative electrode 5 of the battery, effectively reducing the puncture of the SEI film caused by dendrite growth and volume increase. , SEI film is not easy to rupture.
  • the concave place of the curved lithium sheet becomes an area for effectively storing the electrolyte 7. Even after a certain number of cycles of the lithium metal battery, the electrolyte 7 can still be kept infiltrated.
  • the curved lithium sheet increases the effective surface area of the negative electrode 5 of the battery, enhances the electrochemical reaction kinetics, and increases the lithium ion migration path, which is conducive to maintaining the battery capacity and cycle efficiency of the lithium metal battery and prolonging the service life.
  • the cycle performance test of the lithium metal battery with the curved lithium sheet negative electrode of this embodiment was carried out using the LAND CT2001A battery test system.
  • the reversible capacity of the lithium metal battery based on the negative electrode 5 of the curved lithium sheet battery can still reach 86.1 mAh g -1 after 40 cycles at 2C rate, and the capacity retention rate exceeds 81.5%.
  • the reversible capacity of the lithium metal battery based on the negative electrode 5 of the planar lithium sheet battery is only 74.9 mAh g -1 , and the capacity retention rate is only 71.4%.
  • the test results show that the curved lithium sheet can greatly improve the capacity retention rate and cycle stability of lithium metal batteries, can inhibit lithium dendrites, prevent the powdering of negative lithium metal, and improve the cycle stability of lithium batteries, thereby improving lithium metal batteries. cycle life.
  • the lithium iron phosphate half cell based on the negative electrode 5 of the curved lithium sheet battery has better advantages and effectiveness than the lithium iron phosphate half cell based on the negative electrode 5 of the flat lithium sheet battery.
  • an elastic device is provided on the negative electrode 5 of the battery, and both ends of the elastic device are respectively abutted against the negative electrode 5 of the battery and the other end of the battery case 2 .
  • the elastic device is a conductor, which is in close contact with the negative electrode 5 of the battery and the battery case 2 to ensure good conductivity inside the lithium metal battery.
  • the elastic device is an elastic piece 4 .
  • a gasket 3 is provided between the elastic sheet 4 and the negative electrode 5 of the battery, and both ends of the gasket 3 are respectively abutted against the elastic sheet 4 and the negative electrode 5 of the battery.
  • the arrangement of the gasket 3 increases the contact area between the elastic sheet 4 and the negative electrode 5 of the battery, which is beneficial to maintain good conductivity inside the lithium metal battery.
  • the height of the curved lithium sheet is less than 10mm.
  • the curved surface of the curved lithium sheet is in the three-dimensional space coordinate system, with O as the origin, the x and y axes as the two axes of the bottom surface, and the z axis as the vertical axis of the vertical bottom surface, and the value range of the z direction is limited to [- 5mm, 5mm], the value range of x and y is any real number, and the unit is millimeter (any space surface except plane).
  • the electrode sheet 1 is made of a curved lithium sheet. That is, both the electrode sheet 1 and the negative electrode 5 of the lithium symmetric battery are made of curved lithium sheets.
  • the polarization voltage of the lithium symmetric battery using the curved lithium sheet for both the electrode sheet 1 and the negative electrode 5 is about 900,000 seconds after cycling at a current density of 3 mA/cm 2 and a deposition capacity of 1 mAh/cm 2 for about 900,000 seconds. Only 0.16V. Under the same conditions, the polarization voltage of the lithium symmetric battery based on the planar lithium sheet has reached 0.16 V after cycling for about 340,000 seconds. At 0.38 V, the separator 6 has been punctured by overgrown dendrites, causing a local short circuit, which in turn leads to disordered polarization voltages in subsequent cycles. The results show that the curved lithium sheet effectively inhibits the growth of lithium dendrites in the lithium symmetric battery and reduces the polarization voltage.
  • the battery based on the negative electrode 5 of the curved lithium sheet battery has a longer life and higher safety than the battery based on the ordinary flat lithium sheet.
  • the preparation method of the curved lithium sheet is as follows: the flat lithium sheet is formed by imprinting and rolling to form a curved surface.
  • the preparation method of the curved lithium sheet includes the following steps:
  • a layer of polypropylene film is spread on the surface of the flat lithium sheet, placed in the center of the jaws of the precision drilling machine fixture, and then the curved mold is aligned with the flat lithium sheet and placed above the flat lithium sheet.
  • the polypropylene film is placed between the curved mold and the flat lithium sheet, so that after the pressing is completed, the curved mold and the curved lithium sheet are easily separated and will not stick together.
  • the curved mold is manufactured using 3D printing methods.
  • 3D printing of curved molds includes the following steps,
  • the modeling software Solidworks is used for modeling, and the output is in stp format.
  • Use slicing software to slice the surface model according to the print settings, and output the slice images in png format.
  • Use the DLP printer to set the parameters to print the slices layer by layer to obtain a curved mold.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
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Abstract

本发明涉及一种具有曲面锂片负极的锂金属电池，包括电池壳体，电池壳体内设有隔膜，隔膜两端分别连接于电池壳体中部，隔膜与电池壳体一端之间设有第一容腔，隔膜与电池壳体另一端之间设有第二容腔，第一容腔内设有电极片，电极片抵接于电池壳体一端，第二容腔内设有电池负极，电池负极两端分别抵接于隔膜与电池壳体另一端，电池负极由曲面锂片制成，第一容腔和第二容腔内均填充有电解液，电极片和电池负极分别浸润于电解液。曲面锂片延展了电池负极SEI膜的面积，有效减少了枝晶生长，SEI膜不易破裂。能够始终保持电解液浸润，增强了电化学反应动力学，增加了锂离子迁移路径，有利于维持锂金属电池的电池容量和循环效率，延长了使用寿命。

Description

一种具有曲面锂片负极的锂金属电池 技术领域
本发明涉及锂电池技术领域，特别是涉及一种具有曲面锂片负极的锂金属电池。
背景技术
消费电子领域、新能源汽车领域、储能领域对锂电池的容量、寿命及安全性提出了越来越高的要求，具有高容量、长寿命兼具高安全性的锂电池的需求及其迫切。
目前，金属锂由于其高理论比容量(3860mAh/g)、所有金属中最负的电负性，被认为是锂二次电池的最优解决方案。因此，锂金属电池已广泛应用于各个领域。
然而，现有技术的锂金属电池存在以下技术问题：容易出现锂金属粉化或枝晶，进而造成锂电池低的库伦效率及电池容量减少，降低了循环效率和使用寿命。
因此，目前迫切需要开发出一种能够抑制锂枝晶、防止负极锂金属粉化、提升锂电池循环稳定性的锂金属电池。
发明内容
针对现有技术中存在的技术问题，本发明的目的是：提供一种具有曲面锂片负极的锂金属电池，能够抑制锂枝晶生长，防止负极锂金属粉化，提升锂电池循环稳定性，延长使用寿命。
为了达到上述目的，本发明采用如下技术方案：
一种具有曲面锂片负极的锂金属电池，包括电池壳体，电池壳体内设有隔膜，隔膜两端分别连接于电池壳体中部，隔膜与电池壳体一端之间设有第一容腔，隔膜与电池壳体另一端之间设有第二容腔，第一容腔内设有电极片，电极片抵接于电池壳体一端，第二容腔内设有电池负极，电池负极两端分别抵接于隔膜与电池壳体另一端，电池负极由曲面锂片制成，第一容腔和第二容腔内均填充有电解液，电极片和电池负极分别浸润于电解液。
进一步，电池负极上设有弹性装置，弹性装置两端分别抵接于电池负极和电池壳体另一端。
进一步，弹性装置为弹片。
进一步，弹片与电池负极之间设有垫片，垫片两端分别抵接于弹片和电池负极。
进一步，电极片由曲面锂片制成。
进一步，曲面锂片包括若干凹陷部，凹陷部的高度小于10mm。
进一步，曲面锂片的制备方法为，对平面锂片采用压印、辊压方式进行曲面构造制成。
进一步，曲面锂片的制备方法包括以下步骤，
制备所需曲面锂片形状的曲面模具；
将聚丙烯薄膜和曲面模具依次铺于平面锂片表面，并用夹具夹紧曲面模具、聚丙烯薄膜和平面锂片；
用加压装置压制于曲面模具，使平面锂片形成与曲面模具相同的曲面；
取出曲面模具和聚丙烯薄膜，得到所需曲面锂片。
进一步，曲面模具采用3D打印方法制造。
进一步，曲面模具的3D打印包括以下步骤，
使用建模软件对所需曲面锂片进行建模得到曲面模型；
使用切片软件对曲面模型进行切片得到多个切片图片；
对多个切片图片逐层打印，获得曲面模具。
总的说来，本发明具有如下优点：
由于曲面锂片本身具备一定曲率，在锂成核过程中，隆起的锂核将SEI膜顶起时导致的SEI膜面积改变变小，不易顶破，从而有效预防了SEI膜破裂，曲面锂片的曲面有效延展了电池负极SEI膜的面积，有效减少了枝晶生长、体积增大导致的对SEI膜的穿刺，SEI膜不易破裂。而且由于曲面锂片与隔膜的接触为线接触，曲面锂片凹陷的地方成为了有效存储电解液的区域，即使在锂金属电池循环一定次数后，也仍然能够始终保持电解液浸润。曲面锂片增大了电池负极的有效表面积，增强了电化学反应动力学，增加了锂离子迁移路径，有利于维持锂金属电池的电池容量和循环效率，延长了使用寿命。
附图说明
图1为实施例1中的磷酸铁锂半电池装配示意图。
图2为实施例1中分别用曲面锂片和平面锂片做电池负极的磷酸铁锂半电池在2C条件下的放电比容量及库伦效率曲线图。
图3为实施例2中采用曲面锂片和平面锂片作为电极片和电池负极的锂对称电池的循环电压曲线图。
附图标记说明：
1-电极片，2-电池壳体，3-垫片，4-弹片，5-电池负极，6-隔膜，7-电解液。
具体实施方式
下面来对本发明做进一步详细的说明。
实施例1
如图1所示，一种具有曲面锂片负极的锂金属电池，包括电池壳体2，电池壳体2内设有隔膜6，隔膜6两端分别连接于电池壳体2中部，隔膜6与电池壳体2一端之间设有第一容腔，隔膜6与电池壳体2另一端之间设有第二容腔，第一容腔内设有电极片1，电极片1抵接于电池壳体2一端，第二容腔内设有电池负极5，电池负极5两端分别抵接于隔膜6与电池壳体2另一端，电池负极5由曲面锂片制成，第一容腔和第二容腔内均填充有电解液7，电极片1和电池负极5分别浸润于电解液7。
本实施例采用磷酸铁锂作为电极片1活性材料(面密度14.5mg/cm 2)。锂金属电池放电时，曲面锂片制成的电池负极5开始脱锂，锂离子经过隔膜6进入到电解液7中，随后与电极片1上面的活性物质接触，发生嵌锂反应；与此同时，电子从电池壳体2另一端进入到电池壳体2一端；由于电极片1抵接于电池壳体2一端，因而电子随后便进入到电极片1的活性物质里与锂离子进行电荷中和，完成锂金属电池的放电过程。锂金属电池充电时，锂离子首先从电极片1上的活性物质里面脱离，进入到电解液7中，随后通过隔膜6与曲面锂片接触；电子从电极片1上面的活性物质转移出来，先后经过电池壳体2一端、电池壳体2另一端与曲面锂片上的锂离子进行电荷平衡，完成充电过程。
锂金属负极稳定性的提升是保证锂电池技术发展的一个关键研究方向。申请人独特地发现，现有技术的锂金属电池产生锂枝晶快速生长和降低锂金属电池性能的主要原因为其采用了平面锂片为电池负极5。
由于金属锂具有很高的反应活性，在传统液态电解液中形成的固态电解质界面膜(SEI膜)并不稳定，易造成电池容量、循环效率及寿命的降低。另一方 面，在锂电池充放电循环中，锂负极上会不断发生沉积、剥离，产生较大的体积变化，易造成锂金属粉化或枝晶，进而造成锂电池低的库伦效率及容量减少。
具体为，在现有技术的锂金属电池放电过程中，平面锂片负极失去电子，锂离子在平面锂片负极表面成核，平面锂片上的SEI膜同为平面，在锂成核后会将SEI膜顶破，从而使得SEI膜上产生裂隙，锂离子在裂隙上继续沉积，导致了锂枝晶的快速生长。同时，由于平面锂片与隔膜6的接触为平面接触，在锂金属电池循环一定次数后，在平面锂片上成核、生长枝晶，导致平面锂片上的某些位置不再被电解液7浸润，从而降低了锂金属电池的性能。
为了解决上述技术问题，本发明创造性地采用曲面锂片为电池负极5，由于曲面锂片本身具备一定曲率，在锂成核过程中，隆起的锂核将SEI膜顶起时导致的SEI膜面积改变变小，不易顶破，从而有效预防了SEI膜破裂，曲面锂片的曲面有效延展了电池负极5的SEI膜的面积，有效减少了枝晶生长、体积增大导致的对SEI膜的穿刺，SEI膜不易破裂。而且由于曲面锂片与隔膜6的接触为线接触，曲面锂片凹陷的地方成为了有效存储电解液7的区域，即使在锂金属电池循环一定次数后，也仍然能够始终保持电解液7浸润。曲面锂片增大了电池负极5的有效表面积，增强了电化学反应动力学，增加了锂离子迁移路径，有利于维持锂金属电池的电池容量和循环效率，延长了使用寿命。
使用LAND CT2001A电池测试系统对本实施例的具有曲面锂片负极的锂金属电池进行循环性能测试。
从图2可以看出，基于曲面锂片电池负极5的锂金属电池在2C倍率下循环40次后，其可逆容量依然可以达到86.1mAh g -1，容量保持率超过81.5％。而同等条件下，基于平面锂片电池负极5的锂金属电池的可逆容量只有74.9mAh g -1，容量保持率仅有71.4％。测试结果表明，曲面锂片对锂金属电池的容量保持率、 循环稳定性有较大提升，能够抑制锂枝晶，防止负极锂金属粉化，提升锂电池循环稳定性，从而提升了锂金属电池的循环寿命。
通过以上实验可知，基于曲面锂片电池负极5的磷酸铁锂半电池相对于基于平面锂片电池负极5的磷酸铁锂半电池具有更好的优越性和有效性。
进一步，电池负极5上设有弹性装置，弹性装置两端分别抵接于电池负极5和电池壳体2另一端。
弹性装置为导电体，其与电池负极5和电池壳体2紧密接触，保证了锂金属电池内部的良好导电性。
优选地，弹性装置为弹片4。
弹片4与电池负极5之间设有垫片3，垫片3两端分别抵接于弹片4和电池负极5。
垫片3的设置增加了弹片4与电池负极5的接触面积，有利于维持锂金属电池内部的良好导电性。
曲面锂片的高度小于10mm。
具体地，曲面锂片的曲面为在三维空间坐标系内，以O为原点，以x、y轴为底面两轴，以z轴为垂直底面的竖轴，限制z方向取值范围为[-5mm，5mm]，x、y取值范围为任意实数取值，单位为毫米(除平面外的任意空间曲面)。
实施例2
本实施例与实施例1的不同之处在于：电极片1由曲面锂片制成。即锂对称电池的电极片1和电池负极5均采用曲面锂片制成。
使用LAND CT2001A电池测试系统对本实施例的锂对称电池进行恒流循环性能测试。
从图3可以看出，电极片1和电池负极5均采用曲面锂片的锂对称电池在 3mA/cm 2的电流密度，1mAh/cm 2的沉积容量下循环约900000秒后，其极化电压仅有0.16V。而同等条件下，基于平面锂片的锂对称电池的极化电压在循环约340000秒后已达到0.16V，在后续循环中，极化电压持续增大，在循环约560000秒后极化电压达到0.38V，隔膜6已被过度生长的枝晶戳破，造成局部短路，进而导致后面循环中紊乱的极化电压。结果表明，曲面锂片有效抑制了锂对称电池的锂枝晶生长，降低了极化电压。
通过以上实验可知，基于曲面锂片电池负极5的电池相对于基于普通平面锂片的电池具有更长的寿命，安全性更高。
实施例3
曲面锂片的制备方法为，对平面锂片采用压印、辊压方式进行曲面构造制成。
可选地，曲面锂片的制备方法包括以下步骤，
制备所需曲面锂片形状的曲面模具；将聚丙烯薄膜和曲面模具依次铺于平面锂片表面，并用夹具夹紧曲面模具、聚丙烯薄膜和平面锂片；用加压装置压制于曲面模具，使平面锂片形成与曲面模具相同的曲面；取出曲面模具和聚丙烯薄膜，得到所需曲面锂片。
具体地，将一层聚丙烯薄膜铺在平面锂片表面，置于精密钻床夹具钳口中心位置，之后将曲面模具对准平面锂片置于平面锂片上方。正向旋转精密钻床夹具手柄，对钳口所夹物加压，完成压制动作，然后逆向旋转精密钻床夹具手柄，取出所夹物，将曲面锂片取出。
将聚丙烯薄膜设于曲面模具和平面锂片之间，使得压制完成后，曲面模具与曲面锂片容易分开，不会粘连在一起。
可选地，曲面模具采用3D打印方法制造。
曲面模具的3D打印包括以下步骤，
使用建模软件对所需曲面锂片进行建模得到曲面模型；
使用切片软件对曲面模型进行切片得到多个切片图片；
对多个切片图片逐层打印，获得曲面模具。
具体地，使用建模软件Solidworks进行建模，并输出为stp格式。使用切片软件对曲面模型按照打印设置进行切片，并输出为png格式的切片图片。使用DLP打印机设置参数对切片逐层打印，获得曲面模具。
上述实施例为本发明较佳的实施方式，但本发明的实施方式并不受上述实施例的限制，其他的任何未背离本发明的精神实质与原理下所作的改变、修饰、替代、组合、简化，均应为等效的置换方式，都包含在本发明的保护范围之内。

Claims (10)

  1. 一种具有曲面锂片负极的锂金属电池，其特征在于：包括电池壳体，电池壳体内设有隔膜，隔膜两端分别连接于电池壳体中部，隔膜与电池壳体一端之间设有第一容腔，隔膜与电池壳体另一端之间设有第二容腔，第一容腔内设有电极片，电极片抵接于电池壳体一端，第二容腔内设有电池负极，电池负极两端分别抵接于隔膜与电池壳体另一端，电池负极由曲面锂片制成，第一容腔和第二容腔内均填充有电解液，电极片和电池负极分别浸润于电解液。
  2. 按照权利要求1所述的一种具有曲面锂片负极的锂金属电池，其特征在于：电池负极上设有弹性装置，弹性装置两端分别抵接于电池负极和电池壳体另一端。
  3. 按照权利要求2所述的一种具有曲面锂片负极的锂金属电池，其特征在于：弹性装置为弹片。
  4. 按照权利要求3所述的一种具有曲面锂片负极的锂金属电池，其特征在于：弹片与电池负极之间设有垫片，垫片两端分别抵接于弹片和电池负极。
  5. 按照权利要求1所述的一种具有曲面锂片负极的锂金属电池，其特征在于：电极片由曲面锂片制成。
  6. 按照权利要求1-5任一项所述的一种具有曲面锂片负极的锂金属电池，其特征在于：曲面锂片包括若干凹陷部，凹陷部的高度小于10mm。
  7. 按照权利要求6所述的一种具有曲面锂片负极的锂金属电池，其特征在于：曲面锂片的制备方法为，对平面锂片采用压印、辊压方式进行曲面构造制成。
  8. 按照权利要求6所述的一种具有曲面锂片负极的锂金属电池，其特征在于：曲面锂片的制备方法包括以下步骤，
    制备所需曲面锂片形状的曲面模具；
    将聚丙烯薄膜和曲面模具依次铺于平面锂片表面，并用夹具夹紧曲面模具、聚丙烯薄膜和平面锂片；
    用加压装置压制于曲面模具，使平面锂片形成与曲面模具相同的曲面；
    取出曲面模具和聚丙烯薄膜，得到所需曲面锂片。
  9. 按照权利要求8所述的一种具有曲面锂片负极的锂金属电池，其特征在于：曲面模具采用3D打印方法制造。
  10. 按照权利要求9所述的一种具有曲面锂片负极的锂金属电池，其特征在于：曲面模具的3D打印包括以下步骤，
    使用建模软件对所需曲面锂片进行建模得到曲面模型；
    使用切片软件对曲面模型进行切片得到多个切片图片；
    对多个切片图片逐层打印，获得曲面模具。
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04163861A (ja) * 1990-10-26 1992-06-09 Japan Storage Battery Co Ltd 非水電解質二次電池
CN101290987A (zh) * 2008-06-05 2008-10-22 天津中能锂业有限公司 扣式锂电池负极及其加工方法和包含该负极的扣式锂电池
CN112072076A (zh) * 2020-07-22 2020-12-11 宁波大学 一种锂金属电池负极表面的改性方法
CN112802997A (zh) * 2021-02-24 2021-05-14 华南理工大学 一种具有曲面锂片负极的锂金属电池

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN201069801Y (zh) * 2007-07-05 2008-06-04 濮阳迈奇科技有限公司 双负极锂电池
CN103606684B (zh) * 2013-11-20 2015-09-30 惠州亿纬锂能股份有限公司 扣式电池及扣式电池集流器
CN105552348B (zh) * 2015-11-23 2018-03-30 天津赫维科技有限公司 一种3v可充扣式锂电池锂铝合金负极的制作方法
CN205900693U (zh) * 2016-07-14 2017-01-18 深圳市盛邦科技有限公司 一种负极片及全固态电池
CN107565088B (zh) * 2017-07-13 2021-01-08 天津理工大学 一种金属锂二次电池负极的制备方法
CN108574083A (zh) * 2018-05-02 2018-09-25 南方科技大学 一种有效抑制锂金属电池枝晶不可控生长的锂片、其制备方法及用途
CN108847474B (zh) * 2018-06-26 2021-06-08 桑顿新能源科技有限公司 一种预补锂的微织构化负极片及其制备方法
CN110854436B (zh) * 2019-11-28 2021-11-30 广东工业大学 一种二次锂金属电池电解液及其制备方法

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04163861A (ja) * 1990-10-26 1992-06-09 Japan Storage Battery Co Ltd 非水電解質二次電池
CN101290987A (zh) * 2008-06-05 2008-10-22 天津中能锂业有限公司 扣式锂电池负极及其加工方法和包含该负极的扣式锂电池
CN112072076A (zh) * 2020-07-22 2020-12-11 宁波大学 一种锂金属电池负极表面的改性方法
CN112802997A (zh) * 2021-02-24 2021-05-14 华南理工大学 一种具有曲面锂片负极的锂金属电池

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