CN106328897A - 一种汽车电池用复合负极材料的制备方法 - Google Patents

一种汽车电池用复合负极材料的制备方法 Download PDF

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CN106328897A
CN106328897A CN201610862282.5A CN201610862282A CN106328897A CN 106328897 A CN106328897 A CN 106328897A CN 201610862282 A CN201610862282 A CN 201610862282A CN 106328897 A CN106328897 A CN 106328897A
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钟静琴
钟静清
韦晗
陶佳
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Liuzhou Shentong Automobile Technology Co Ltd
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Abstract

本发明涉及汽车电池负极材料,具体说是一种汽车电池用复合负极材料的制备方法,其包括将氧化石墨烯置于盛有HCl溶液的容器中,用去离子水分散并搅拌;然后将上述混合物置于微爆反应器中,加入KClO3溶液,再加入H2O2完成微爆反应,得到具有卷曲构造的氧化石墨烯纳米卷;将上述氧化石墨烯纳米卷和SnCl4按一定质量比溶于水中混合均匀;然后加入还原剂反应,并过滤、洗涤、干燥,得到SnO2/石墨烯纳米卷复合负极材料。本发明在石墨烯纳米卷上复合二氧化锡材料,制备得到的材料性能相较于石墨烯与二氧化锡复合材料具有更优的储氢性能,将其作为新能源汽车电池的负极,可大大提高电池的使用性能,延长电池的使用寿命。

Description

一种汽车电池用复合负极材料的制备方法
技术领域
本发明涉及汽车电池用负极材料,具体说是一种汽车电池用复合负极材料的制备方法。
背景技术
卷曲的石墨烯作为一种新型的纳米结构引起了一些研究者的注意,名为石墨烯纳米卷,其发现可追溯到1960年,石墨烯纳米卷具有准一维结构,是由平面石墨烯螺旋卷曲而成,其半径的大小取决于石墨的尺寸和卷曲的曲率。此外,非封闭状态的两端和内外边缘可以提高石墨烯纳米卷的储氢能力,可用于作为超级电容器或电池的电极材料,尤其是作为新能源汽车的电池负极材料,成新的研发方向;在石墨烯纳米卷层间键作用下,可调的层间距能影响石墨烯纳米卷的电子转移及光学特性。因此,石墨烯纳米卷己成为石墨烯基纳米材料的研究热点之一。
目前,石墨烯纳米卷的制备和应用远落后于石墨烯和碳纳米管,其研究也只集中在结构和性能的理论计算和计算机仿真研究。采用化学法合成出石墨与金属K的插层化合物,然后对其超声处理,首次制备出石墨烯纳米卷,并提出了石墨烯纳米卷具有比石墨烯更显著的储氢能力和拥有六倍于石墨烯的超大电容的假设。该方法必需在无水无氧等复杂且苛刻条件下进行,因此,在大规模制备和应用方面受到一定限制。此外,关于SnO2/石墨烯复合材料的制备报道很多,但具体的SnO2/石墨烯纳米卷复合材料确未见记载。
发明内容
为了克服现有技术的不足,本发明提供了一种可制备SnO2/石墨烯纳米卷复合负极材料的制备方法,该方法简单,所制备的材料具有优异的储氢性能以及电容性能。
本发明解决上述技术问题所采用的技术方案为:一种汽车电池用复合负极材料的制备方法,其包括以下步骤:
(1)将氧化石墨烯置于盛有HCl溶液的容器中,用去离子水分散并搅拌;
(2)然后将上述混合物置于微爆反应器中,加入KClO3溶液,再加入H2O2完成微爆反应,得到具有卷曲构造的氧化石墨烯纳米卷;
(3)将上述氧化石墨烯纳米卷和SnCl4按一定质量比溶于水中混合均匀;
(4)然后加入还原剂反应,并过滤、洗涤、干燥,得到SnO2/石墨烯纳米卷复合负极材料。
作为优选,所述氧化石墨烯用量为0.5-1g,HCl溶液的浓度为1mol/L,用量为60-100mL。
作为优选,采用搅拌器搅拌4-13h。
作为优选,KClO3溶液采用逐滴加入的方式,浓度为1mol/L,用量为10-20mL。
作为优选,KClO3溶液滴加完成后,再加入50-100mL30%的H2O2
作为优选,氧化石墨烯纳米卷与SnCl4的质量比为(2-10)。
作为优选,还原剂采用水合肼或硼氢化钠,反应时间10-24h。
从以上技术方案可知,本发明在石墨烯纳米卷上复合二氧化锡材料,制备得到的材料性能相较于石墨烯与二氧化锡复合材料具有更优的储氢性能,将其作为新能源汽车电池的负极,可大大提高电池的使用性能,延长电池的使用寿命。
具体实施方式
下面将详细说明本发明,在此本发明的示意性实施例以及说明用来解释本发明,但并不作为对本发明的限定。
一种汽车电池用复合负极材料的制备方法,其包括以下步骤:
将0.5-1g氧化石墨烯置于盛有60-100mL 1mol/L的 HCl溶液的容器中,用去离子水分散并采用搅拌器搅拌4-13h;然后将上述混合物置于微爆反应器中,逐滴加入10-20mL1mol/L 的KClO3溶液,KClO3溶液滴加完成后再加入50-100mL30%的H2O2完成微爆反应,得到具有卷曲构造的氧化石墨烯纳米卷;
接着将上述氧化石墨烯纳米卷和SnCl4按质量比(2-10)溶于水中混合均匀,然后加入还原剂水合肼或硼氢化钠,反应10-24h后,过滤并用去离子水反复洗涤,干燥即可得到SnO2/石墨烯纳米卷复合负极材料。
实施例1
称取0.5g的氧化石墨烯和60 mL 1mol/LHCl烧瓶中,用去离子水分散并用搅拌器搅拌4h,然后将得到的混合物置于微爆反应器中,逐滴加入10mL 1mol/L KClO3到微爆反应器中,滴加完成后再加入50mL30%的H2O2完成微爆反应,最终得到具有卷曲构造的氧化石墨烯纳米卷;将制得的氧化石墨烯纳米卷和SnCl4按质量比1:5溶于水中混合均匀,后加入还原剂水合肼,反应10h后,过滤并用去离子水反复洗涤,干燥即可得SnO2/石墨烯纳米卷复合材料。
将上述材料作为汽车电池的负极,测试得到:电极在600mA·g-1的充放电电流密度、0.05-3.0 V电压下的循环性能显现出较大的性能改善,首次放电容量达2770 mAh·g-1,充电容量为1540 mAh·g-1, 首次库仑效率约56%, 100 个循环后放电容量约820mAh·g-1
实施例2
称取1g的氧化石墨烯和80 mL 1mol/LHCl烧瓶中,用去离子水分散并用搅拌器搅拌8h,然后将得到的混合物置于微爆反应器中,逐滴加入20mL 1mol/L KClO3到微爆反应器中,滴加完成后再加入70mL30%的H2O2完成微爆反应,最终得到具有卷曲构造的氧化石墨烯纳米卷;将制得的氧化石墨烯纳米卷和SnCl4按1:2比溶于水中混合均匀,后加入还原剂硼氢化钠,反应15h后,过滤并用去离子水反复洗涤,干燥即可得SnO2/石墨烯纳米卷复合材料。
相对于未被包覆的 SnO2材料的电极,将上述材料作为汽车电池的负极,测试得到:电极在600mA·g-1的充放电电流密度、0.05-3.0 V电压下的循环性能显现出较大的性能改善,首次放电容量达2580 mAh·g-1,充电容量为1720 mAh·g-1, 首次库仑效率约67%,在100 个循环后放电容量从 170mAh·g-1改善至 920mAh·g-1
实施例3
称取1g的氧化石墨烯和100 mL 1mol/LHCl烧瓶中,用去离子水分散并用搅拌器搅拌13h,然后将得到的混合物置于微爆反应器中,逐滴加入10mL 1mol/L KClO3到微爆反应器中,滴加完成后再加入50-100mL30%的H2O2完成微爆反应,最终得到具有卷曲构造的氧化石墨烯纳米卷;将制得的氧化石墨烯纳米卷和SnCl4按质量比1:10溶于水中混合均匀,后加入还原剂水合肼,反应24h后,过滤并用去离子水反复洗涤,干燥即可得SnO2/石墨烯纳米卷复合材料。
将上述材料作为汽车电池的负极,测试得到:电极在600mA·g-1的充放电电流密度、0.05-3.0 V电压下的循环性能显现出较大的性能改善,首次放电容量达2470 mAh·g-1,充电容量为1460 mAh·g-1, 首次库仑效率约60%,在100 个循环后放电容量为 890mAh·g-1
以上对本发明实施例所提供的技术方案进行了详细介绍,本文中应用了具体个例对本发明实施例的原理以及实施方式进行了阐述,以上实施例的说明只适用于帮助理解本发明实施例的原理;同时,对于本领域的一般技术人员,依据本发明实施例,在具体实施方式以及应用范围上均会有改变之处,综上所述,本说明书内容不应理解为对本发明的限制。

Claims (7)

1.一种汽车电池用复合负极材料的制备方法,其包括以下步骤:
(1)将氧化石墨烯置于盛有HCl溶液的容器中,用去离子水分散并搅拌;
(2)然后将上述混合物置于微爆反应器中,加入KClO3溶液,再加入H2O2完成微爆反应,得到具有卷曲构造的氧化石墨烯纳米卷;
(3)将上述氧化石墨烯纳米卷和SnCl4按一定质量比溶于水中混合均匀;
(4)然后加入还原剂反应,并过滤、洗涤、干燥,得到SnO2/石墨烯纳米卷复合负极材料。
2.根据权利要求1所述汽车电池用复合负极材料的制备方法,其特征在于:所述氧化石墨烯用量为0.5-1g,HCl溶液的浓度为1mol/L,用量为60-100mL。
3.根据权利要求2所述汽车电池用复合负极材料的制备方法,其特征在于:采用搅拌器搅拌4-13h。
4.根据权利要求3所述汽车电池用复合负极材料的制备方法,其特征在于:KClO3溶液采用逐滴加入的方式,浓度为1mol/L,用量为10-20mL。
5.根据权利要求4所述汽车电池用复合负极材料的制备方法,其特征在于:KClO3溶液滴加完成后,再加入50-100mL30%的H2O2
6.根据权利要求5所述汽车电池用复合负极材料的制备方法,其特征在于:氧化石墨烯纳米卷与SnCl4的质量比为1:(2-10)。
7.根据权利要求6所述汽车电池用复合负极材料的制备方法,其特征在于:还原剂采用水合肼或硼氢化钠,反应时间10-24h。
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