CN113851644A - 一种银掺杂硅酸亚铁锂正极材料及其制备方法 - Google Patents
一种银掺杂硅酸亚铁锂正极材料及其制备方法 Download PDFInfo
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- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 title claims abstract description 37
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 title claims abstract description 34
- 229910052744 lithium Inorganic materials 0.000 title claims abstract description 34
- 239000010406 cathode material Substances 0.000 title claims abstract description 23
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 title claims abstract description 22
- 238000002360 preparation method Methods 0.000 title claims abstract description 15
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 38
- 239000000463 material Substances 0.000 claims abstract description 34
- SQGYOTSLMSWVJD-UHFFFAOYSA-N silver(1+) nitrate Chemical compound [Ag+].[O-]N(=O)=O SQGYOTSLMSWVJD-UHFFFAOYSA-N 0.000 claims abstract description 30
- 229910052742 iron Inorganic materials 0.000 claims abstract description 17
- 229910001961 silver nitrate Inorganic materials 0.000 claims abstract description 15
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 11
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 11
- 239000010703 silicon Substances 0.000 claims abstract description 11
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- 239000000126 substance Substances 0.000 claims abstract description 5
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- QSNQXZYQEIKDPU-UHFFFAOYSA-N [Li].[Fe] Chemical compound [Li].[Fe] QSNQXZYQEIKDPU-UHFFFAOYSA-N 0.000 claims description 20
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 claims description 18
- CIWBSHSKHKDKBQ-JLAZNSOCSA-N Ascorbic acid Chemical compound OC[C@H](O)[C@H]1OC(=O)C(O)=C1O CIWBSHSKHKDKBQ-JLAZNSOCSA-N 0.000 claims description 12
- BOTDANWDWHJENH-UHFFFAOYSA-N Tetraethyl orthosilicate Chemical compound CCO[Si](OCC)(OCC)OCC BOTDANWDWHJENH-UHFFFAOYSA-N 0.000 claims description 12
- XIXADJRWDQXREU-UHFFFAOYSA-M lithium acetate Chemical compound [Li+].CC([O-])=O XIXADJRWDQXREU-UHFFFAOYSA-M 0.000 claims description 12
- 238000003756 stirring Methods 0.000 claims description 10
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims description 9
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 claims description 9
- WMFOQBRAJBCJND-UHFFFAOYSA-M Lithium hydroxide Chemical compound [Li+].[OH-] WMFOQBRAJBCJND-UHFFFAOYSA-M 0.000 claims description 9
- MCDLETWIOVSGJT-UHFFFAOYSA-N acetic acid;iron Chemical compound [Fe].CC(O)=O.CC(O)=O MCDLETWIOVSGJT-UHFFFAOYSA-N 0.000 claims description 8
- 229960002413 ferric citrate Drugs 0.000 claims description 8
- NPFOYSMITVOQOS-UHFFFAOYSA-K iron(III) citrate Chemical compound [Fe+3].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O NPFOYSMITVOQOS-UHFFFAOYSA-K 0.000 claims description 8
- 239000008139 complexing agent Substances 0.000 claims description 7
- PAZHGORSDKKUPI-UHFFFAOYSA-N lithium metasilicate Chemical compound [Li+].[Li+].[O-][Si]([O-])=O PAZHGORSDKKUPI-UHFFFAOYSA-N 0.000 claims description 7
- 229910052912 lithium silicate Inorganic materials 0.000 claims description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 7
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 6
- 239000011668 ascorbic acid Substances 0.000 claims description 6
- 229960005070 ascorbic acid Drugs 0.000 claims description 6
- 235000010323 ascorbic acid Nutrition 0.000 claims description 6
- 230000000536 complexating effect Effects 0.000 claims description 6
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- 229910021641 deionized water Inorganic materials 0.000 claims description 6
- 238000010438 heat treatment Methods 0.000 claims description 6
- VCJMYUPGQJHHFU-UHFFFAOYSA-N iron(3+);trinitrate Chemical compound [Fe+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O VCJMYUPGQJHHFU-UHFFFAOYSA-N 0.000 claims description 6
- 239000000203 mixture Substances 0.000 claims description 6
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- 230000032683 aging Effects 0.000 claims description 4
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- XGZVUEUWXADBQD-UHFFFAOYSA-L lithium carbonate Chemical compound [Li+].[Li+].[O-]C([O-])=O XGZVUEUWXADBQD-UHFFFAOYSA-L 0.000 claims description 3
- 229910052808 lithium carbonate Inorganic materials 0.000 claims description 3
- 235000012239 silicon dioxide Nutrition 0.000 claims description 3
- 239000000377 silicon dioxide Substances 0.000 claims description 3
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- 238000001291 vacuum drying Methods 0.000 claims description 3
- 238000004321 preservation Methods 0.000 claims 1
- 238000000034 method Methods 0.000 abstract description 11
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- 239000004332 silver Substances 0.000 abstract description 5
- 238000011031 large-scale manufacturing process Methods 0.000 abstract description 2
- -1 Silver ions Chemical class 0.000 abstract 2
- 229910001416 lithium ion Inorganic materials 0.000 description 10
- 150000002500 ions Chemical class 0.000 description 9
- 239000010405 anode material Substances 0.000 description 8
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 7
- 229910009731 Li2FeSiO4 Inorganic materials 0.000 description 6
- 230000005540 biological transmission Effects 0.000 description 6
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 4
- 238000002441 X-ray diffraction Methods 0.000 description 4
- 238000005303 weighing Methods 0.000 description 4
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 3
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- 229910021389 graphene Inorganic materials 0.000 description 3
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 239000012300 argon atmosphere Substances 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
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- 239000007774 positive electrode material Substances 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- 229910032387 LiCoO2 Inorganic materials 0.000 description 1
- 229910052493 LiFePO4 Inorganic materials 0.000 description 1
- 229910013872 LiPF Inorganic materials 0.000 description 1
- 101150058243 Lipf gene Proteins 0.000 description 1
- 239000002033 PVDF binder Substances 0.000 description 1
- FKNQFGJONOIPTF-UHFFFAOYSA-N Sodium cation Chemical compound [Na+] FKNQFGJONOIPTF-UHFFFAOYSA-N 0.000 description 1
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- 238000005036 potential barrier Methods 0.000 description 1
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- 238000006479 redox reaction Methods 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 229910001415 sodium ion Inorganic materials 0.000 description 1
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- 238000003860 storage Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 229910052720 vanadium Inorganic materials 0.000 description 1
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical group [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 description 1
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- H01M4/36—Selection of substances as active materials, active masses, active liquids
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- H01M4/54—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of silver
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Abstract
本发明提出的是本发明公开了一种高性能的银掺杂硅酸亚铁锂正极材料,该材料化学分子式为Li2‑xAgxFeSiO4,银离子主要取代锂的位置。本发明还公开了制备所述银掺杂硅酸亚铁锂正极材料的方法,将含有锂源、硝酸银、铁源和硅源的化合物按比例混合均匀,然后在惰性气氛下进行锻烧,经研磨过筛后即可得到银掺杂硅酸亚铁锂材料。本发明通过银离子的掺杂增大了锂的扩散通道,同时改善了电子导电能力,具有较高的电化学活性和优良的倍率充放电性能,且制备方法方法操作简单,成本低廉,易于实现,具有规模化生产的潜力。
Description
技术领域
本发明涉及一种锂离子电池正极材料的制备方法,特别是一种银掺杂硅酸亚铁锂正极材料及其制备方法,属于化学能源材料技术领域。
背景技术
随着人们对高能量锂离子电池需求的日益增长,寻找高安全、高能量密度的电池正极材料成为目前技术领域内研究的重点。聚阴离子结构的硅酸亚铁锂材料(Li2FeSiO4)具有比容量高、安全性好而备受关注,理论上,Li2FeSiO4可以通过Fe2+/Fe4+电对的双电子氧化还原反应而脱嵌两个锂离子,比容量高达331mAh g‒1,约为商业化正极材料如LiCoO2、LiFePO4的2倍。尽管Li2FeSiO4具有双电子反应的理论容量,然而大多数情况下研究者都只能获得单电子反应的容量,这是由于Li2FeSiO4材料的Fe3+/Fe4+电对的电位偏高,难以有效利用;另一方面,由于Li2FeSiO4材料的电子和离子导电率低,材料倍率性能差,在作为锂离子电池正极材料使用时,充放电性能往往无法满足实际应用的需求。
为了提高Li2FeSiO4材料的实际充放电性能,现有技术中已提出了多种改进方案:如申请号为CN 201510061167.3的发明专利《一种高倍率硅酸铁锂正极材料的制备方法》公布了制备纳米多孔硅酸亚铁锂的办法,该方法通过构建纳米多孔材料来增加反应面积,缩短电荷传输距离;申请号为CN 201410136971.9的发明专利《类石墨烯掺杂锂离子电池硅酸铁锂复合正极材料制备方法》公布了石墨烯包覆硅酸亚铁锂的办法,采用类石墨烯掺杂包覆改善材料的电子传输能力;申请号为CN 201210207841.0的发明专利《一种钒掺杂硅酸亚铁锂正极材料及其制备方法》公布了钒掺杂硅酸亚铁锂的制备办法,通过钒掺杂取代铁的位置,提升材料的电子导电能力;等等。以上方案都在一定程度上改善了正极材料的电子传输性能,从而提高正极材料的实际充放电容量,但对材料自身的离子传输性能的提高作用不大。又如申请号为CN 201510908340.9的发明专利申请《一种制备钠掺杂硅酸亚铁锂/碳纳微结构复合正极材料的方法》公开了通过喷雾干燥法制备钠离子掺杂硅酸亚铁锂的方法;然而,由于钠离子的脱出需要更高的势垒,该材料只有在充电到4.8V时才具有较高的容量。因此,急需一种能够克服上述现有材料及制备方法存在的各种缺陷的正极材料,从而满足市场对锂离子电池容量和功效需求。
发明内容
本发明的目的在于解决现有存在的上述问题,提出一种银掺杂硅酸亚铁锂正极材料及其制备方法。
本发明的技术解决方案:一种银掺杂硅酸亚铁锂正极材料,该材料通过将含有锂源、硝酸银、铁源和硅源的化合物按比例混合,通过加入有机络合试剂形成凝胶,然后将干凝胶在惰性气氛下进行锻烧得到;其化学分子式为Li2-xAgxFeSiO4,其中x的范围为0<x≤0.05。该材料的制备方法具体包括如下步骤:
将锂源(醋酸锂、碳酸锂、氢氧化锂)、硝酸银、铁源(硝酸铁、醋酸亚铁、柠檬酸铁)和硅源(正硅酸四乙酯、二氧化硅、硅酸锂)的化合物按比例在去离子水中混合,锂源、硝酸银、铁源和硅源的化合物的物质的量之比为(1.99~1.95):(0.01~0.05):1:1;加入物质的量为铁源的物质的量的1~2倍的有机络合试剂(坏血酸、柠檬酸、醋酸、乙二醇),持续搅拌并加热形成溶胶体系;将溶胶体系在60-90℃下加热,继续搅拌9~12小时直至溶剂蒸发形成凝胶;将凝胶真空干燥陈化后研磨、粉碎,然后在惰性气氛下于600-900℃烧结0.5~24小时,再经冷却、研磨过筛后得到银掺杂硅酸亚铁锂正极材料。
与现有技术相比,本发明的优点在于:
1)本发明通过Ag在Li位的取代掺杂,增大了硅酸亚铁锂晶格中的离子扩散通道,提高了材料的离子迁移性能;
2)本发明通过Ag掺杂引起的体积变化,改变了Fe的电子结构,降低材料的带隙宽度,从而提升了电子的传输速率;
3)本发明制备的银掺杂硅酸亚铁锂正极材料,具有高达165mAh·g−1的放电容量,并且在1C的倍率下具有132mAh·g−1的放电容量;
4)本发明提出的制备方法方法操作简单,成本低廉,易于实现,具有规模化生产的潜力。
附图说明
图1是按实施例1(Li1.99Ag0.01FeSiO4)、实施例2(Li1.97Ag0.03FeSiO4)和实施例3(Li1.95Ag0.05FeSiO4)和实施例4(Li2FeSiO4)所制备的硅酸亚铁锂的X射线衍射花样图。
图2是按实施例1所制备的Li1.99Ag0.01FeSiO4样品的充放电曲线图。
图3是按实施例2所制备的Li1.97Ag0.03FeSiO4样品的电子显微镜图。
图4是按实施例2所制备的Li1.97Ag0.03FeSiO4样品的充放电曲线图。
图5是按实施例3所制备的Li1.95Ag0.05FeSiO4样品的充放电曲线图。
图6是按实施例4所制备的Li2FeSiO4的充放电曲线图。
具体实施方式
下面结合附图进一步说明本发明的技术方案。下面通过参考附图描述的实施例是示例性的,旨在用于解释本发明,而不能理解为对本发明的限制。下文的公开提供了许多不同的实施方式或例子用来实现本发明的不同结构。为了简化本发明的公开,下文中将对特定实施例的部件和设置进行描述。当然,它们仅仅为示例,并且目的不在于限制本发明。此外,本发明可以在不同例子中重复参考数字和/或参考字母,这种重复是为了简化和清楚的目的,其本身不指示所讨论各种实施方式和/或设置之间的关系。此外,本发明提供了的各种特定的工艺和材料的例子,但是本领域普通技术人员可以意识到其他工艺的应用和/或其他材料的使用。
该材料中掺杂的Ag离子主要取代Li离子的位置,因而该材料具有Li2-xAgxFeSiO4的化学式,其中x的范围为0<x≤0.05。由于Ag离子的离子半径比Li离子大,Ag掺杂后会增大离子的扩散通道,从而有利于材料自身的离子传输。在硅酸亚铁锂结构中,锂离子有多条扩散路径,因此Ag掺杂不会阻塞锂的扩散。同时,Ag掺杂后的体积变化可以导致相邻Fe位置的变化,进而改变Fe的电子结构,降低材料的带隙宽度。因此,掺杂材料具有更好的电子和离子传输性能。
一种银掺杂硅酸亚铁锂正极材料及其制备方法,该方法将含有锂源、硝酸银、铁源和硅源的化合物按比例混合,通过加入适当的有机络合试剂形成凝胶,然后将干凝胶在惰性气氛下进行锻烧,即可得到所述的银掺杂硅酸亚铁锂材料,其中掺杂Ag离子主要取代Li离子的位置。该方法具体包括以下步骤:
将锂源、硝酸银、铁源和硅源的化合物按一定比例在水中混合,加入一定量的有机络合剂,持续搅拌并加热形成溶胶;其中锂源选自但不限于醋酸锂、碳酸锂、氢氧化锂,优选为醋酸锂;铁源选自但不限于硝酸铁、醋酸亚铁、柠檬酸铁,优选为醋酸亚铁、柠檬酸铁;硅源选自但不限于正硅酸四乙酯、二氧化硅、硅酸锂,优选为正硅酸四乙酯;有机络合试剂可选用抗坏血酸、柠檬酸、醋酸、乙二醇等,优选为柠檬酸或抗坏血酸。将上述溶胶体系保持在60-90℃,继续搅拌直至溶剂蒸发而形成凝胶;将干燥后的凝胶研磨、粉碎,然后在惰性气氛下在600-900℃烧结0.5-24小时,再经冷却、研磨过筛后得到银掺杂硅酸亚铁锂正极材料。
以下实施例中,硅酸亚铁锂样品的储锂性能测试步骤如下:将硅酸亚铁锂样品、导电剂炭黑和粘结剂PVDF按8:1:1的质量比例混合均匀,然后涂敷在金属铝箔上;干燥后,以铝箔上的复合电极作为工作电极,以金属锂片为对电极,以浓度为1M的LiPF6的EC/DMC溶液为电解液组装成锂电池,然后在1.5-4.6V间进行充放电测试,测试温度为30℃。
实施例1
按物质的量之比1.99:0.01:1:1分别称取醋酸锂、硝酸银、醋酸亚铁和正硅酸四乙酯溶解在去离子水中,并加入与铁源等摩尔的抗坏血酸作为络合剂,在60℃搅拌约12小时形成凝胶,然后在90℃真空干燥12小时。将得到的干凝胶研磨粉碎,然后在650℃于氮气氛围下煅烧18小时,冷却后研磨过筛得到Li1.99Ag0.01FeSiO4产品。如图1所示,所得产品的X射线衍射花样表明制备的材料为单斜结构的硅酸亚铁锂。如图2所示,所得产品材料在0.1C倍率下的放电容量为156mAh g-1,1C的放电容量达到121mAh·g-1。
实施例2
按物质的量之比1.97:0.03:1:1分别称取醋酸锂、硝酸银、柠檬酸铁和正硅酸四乙酯溶解在去离子水中,并加入与铁源等摩尔的柠檬酸作为络合剂,在80℃搅拌约6小时形成凝胶,然后在100℃真空干燥12小时,并继续在90℃陈化12小时。将得到的干凝胶研磨粉碎,然后在700℃于氩气氛围下煅烧12小时,自然冷却后得到Li1.97Ag0.03FeSiO4产品。如图1所示,所得产品的X射线衍射花样表明制备的材料为单斜结构的硅酸亚铁锂。如图3所示,所得产品材料的颗粒尺寸在100nm左右。如图4所示,所得产品材料在0.1C倍率下的放电容量为165mAh g-1,1C倍率下的放电容量达到132mAh·g-1。
实施例3
按物质的量之比1.95:0.05:1:1分别称取醋酸锂、硝酸银、柠檬酸铁和正硅酸四乙酯溶解在去离子水中,并加入铁源2倍摩尔的抗坏血酸作为络合剂,在70℃搅拌约9小时形成凝胶,然后在120℃真空干燥4小时,并继续在100℃陈化12小时。将得到的干凝胶研磨粉碎,然后在850℃于氩气氛围下煅烧2小时,自然冷却后得到Li1.95Ag0.05FeSiO4产品。如图1所示,所得产品的X射线衍射花样表明制备的材料主要为单斜结构的硅酸亚铁锂,但是出现了明显的杂质峰。如图5所示,所得产品材料在0.1C倍率下的放电容量为133mAh·g-1。
实施例4(对比例)
按物质的量之比2:1:1分别称取醋酸锂、醋酸亚铁和正硅酸四乙酯溶解在去离子水中,并加入柠檬酸作为络合剂,在60℃搅拌约12小时形成凝胶,然后在100℃真空干燥12小时,并继续陈化12小时。将所获得的干凝胶进行研磨粉碎,然后在700℃于氮气氛围下煅烧12小时,自然冷却后得到Li2FeSiO4产品。如图6所示,所得硅酸亚铁锂为单斜结构,该对比材料的0.1C放电容量为143mAh·g-1。
以上所述,仅为本发明较佳的具体实施方式,但本发明的保护范围并不局限于此,任何熟悉本技术领域的技术人员在本发明揭露的技术范围内,根据本发明的技术方案及其发明构思加以等同替换或改变,都应涵盖在本发明的保护范围之内。
Claims (10)
1.一种银掺杂硅酸亚铁锂正极材料,其特征在于,该材料通过将含有锂源、硝酸银、铁源和硅源的化合物按比例混合,通过加入有机络合试剂形成凝胶,然后将干凝胶在惰性气氛下进行锻烧得到;其化学分子式为Li2-xAgxFeSiO4,其中x的范围为0<x≤0.05。
2.根据权利要求1所述的一种银掺杂硅酸亚铁锂正极材料,其特征在于,该材料的制备方法具体包括如下步骤:
(1)将锂源、硝酸银、铁源和硅源的化合物按比例在去离子水中混合,加入有机络合试剂,持续搅拌并加热形成溶胶体系;
(2)将步骤(1)制备的溶胶体系保温加热,继续搅拌直至溶剂蒸发形成凝胶;
(3)将步骤(2)制备的凝胶真空干燥陈化后研磨、粉碎,然后在惰性气氛下烧结,再经冷却、研磨过筛后得到银掺杂硅酸亚铁锂正极材料。
3.根据权利要求2所述的一种银掺杂硅酸亚铁锂正极材料,其特征在于,所述锂源、硝酸银、铁源和硅源的化合物的物质的量之比为1.99~1.95:0.01~0.05:1:1。
4.根据权利要求2所述的一种银掺杂硅酸亚铁锂正极材料,其特征在于,所述有机络合试剂的加入量的为铁源的物质的量的1~2倍。
5.根据权利要求2所述的一种银掺杂硅酸亚铁锂正极材料,其特征在于,所述的锂源包括醋酸锂、碳酸锂、氢氧化锂中的一种或多种混合物。
6.根据权利要求2所述的一种银掺杂硅酸亚铁锂正极材料,其特征在于,所述的铁源包括硝酸铁、醋酸亚铁、柠檬酸铁中的一种或多种混合物。
7.根据权利要求2所述的一种银掺杂硅酸亚铁锂正极材料,其特征在于,所述的硅源包括正硅酸四乙酯、二氧化硅、硅酸锂中的一种或多种混合物。
8.根据权利要求2所述的一种银掺杂硅酸亚铁锂正极材料,其特征在于,所述的有机络合试剂包括抗坏血酸、柠檬酸、醋酸、乙二醇中的一种或多种混合物。
9.根据权利要求2所述的一种银掺杂硅酸亚铁锂正极材料,其特征在于,所述步骤(2)中保温加热的加热温度保持在60-90℃,搅拌时间为9~12小时。
10.根据权利要求2所述的一种银掺杂硅酸亚铁锂正极材料,其特征在于,所述步骤(3)中在惰性气氛下烧结的温度为600-900℃,烧结时间为0.5~24小时。
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