CN107170970B - 一种锂电电极材料表面固溶层材料的优化方法 - Google Patents

一种锂电电极材料表面固溶层材料的优化方法 Download PDF

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CN107170970B
CN107170970B CN201710348650.9A CN201710348650A CN107170970B CN 107170970 B CN107170970 B CN 107170970B CN 201710348650 A CN201710348650 A CN 201710348650A CN 107170970 B CN107170970 B CN 107170970B
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黄冰心
胡希韬
强文江
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University of Science and Technology Beijing USTB
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Abstract

本发明属于锂电材料技术领域，特别是一种以锂电正极或负极材料为基体，以力学及导电性能为依据选择固溶体成分，将此固溶体包覆于电极颗粒之上，此表面固溶体层可以提高锂离子电池循环性能从而大大提高电池使用寿命的一种锂电电极材料表面固溶层材料的优化方法。具体为：将基体材料与掺杂材料按特定比例混合，将所述混合物经过一系列工艺制成块体材料，测试块体材料力学性能与导电性能，以力学性能和导电性能为判定依据选出最优成分作为包覆材料，将最优成分包覆于基体颗粒表层后即获得改性电极基体材料。本发明将力学和导电性能测试作为选择依据，相对传统试错法提高了效率，并且更加具有针对性，所制备材料循环性能较原基体材料有了大幅度提高。

Description

一种锂电电极材料表面固溶层材料的优化方法
技术领域
本发明应用在锂电电极材料领域，以力学性能与导电性能为选择依据，应用于锂电电极材料的表面包覆层成分选择的优化方法。
背景技术
锂离子电池被广泛应用于移动电话、笔记本电脑、照相机等移动电子设备。近年来，电动汽车以及储能装置的发展极大地拓宽了锂离子电池的应用领域，同时，对锂离子电池的能量密度和使用寿命也提出了更高的要求。在锂离子电池中，电极材料约占整体重量的30-40%，此外，电极材料的循环稳定性也是决定锂离子电池使用寿命的重要原因之一，因而电极材料是决定电池能量密度和使用寿命的最关键因素。在各类电极材料中，锂过渡金属氧化物材料具有高电极电位、良好的电子和离子导电性、以及锂可逆脱嵌过程中良好的结构稳定性等优点，因此，该类化合物是优良的锂离子电池备选电极材料。
能量密度和循环寿命是表征电极材料电化学性能的重要参数，有趣的是，它们都和电极材料的力学稳定性密切相关。在充放电过程中，电极材料的点阵常数随着锂离子的脱出(或嵌入)会发生变化，如LiCoO2的点阵常数变化达到3%，但应该注意对于脆性的电极材料来说，应变>0.1%即被认为是危险的。而对于给定的电极材料，其能量密度取决于可利用的锂离子分数，当过量锂离子脱出时，材料的力学性能变差，更容易发生断裂，因此，能量密度和力学稳定性相关。即使没有过充发生，电极材料在充放电循环过程中，点阵常数随着锂离子的脱出或嵌入发生周期性变化，因而产生周期性应力，在较小的应力下，电极也会发生断裂、粉化，从而造成电极颗粒接触不良，使电池不再适合进一步循环。因此，电极材料的循环寿命强烈依赖于力学稳定性。
研究证明，表面修饰可有效提高电极材料的循环性能，这通常归因于修饰层能提高表面力学强度，防止裂纹产生。但是，由于缺乏定量的实验数据，目前表面修饰都是采用试错法，其工艺路线如图1，也就是直接在颗粒表面制备固溶体层，然后组装电池，检测电化学性能。优化过程非常复杂，且存在包覆不均匀，包覆层成分难以控制，需要大量工作。尤其对电极材料在充放电过程中的力学-电化学性能耦合作用，即对电极颗粒应力衍变导致的裂纹和颗粒表面修饰强化的机理研究更少。
发明内容
本发明从电极材料表面包覆层的力学和导电性能入手，根据表面修饰层是电极材料固溶体的事实，设计与制备电极材料的固溶体，以力学性能和导电性能作为选择依据，相对传统试错法大大提高了效率。
本发明的技术方案如下：一种锂电电极材料表面固溶层材料的优化方法，该方法具体包括以下步骤：
步骤1：按照设计成分，将基体材料与掺杂材料在一定范围内按照不同的比例分别进行混合；
步骤2：将不同比例的混合材料分别制成块体材料；
步骤3：分别测试步骤2得到的块体材料的力学性能，以力学性能判定依据选出不同成分的块体材料中筛选出最优组分，将最优材料包覆于电极材料表面获得改性电极材料。
进一步，所述步骤1中比例为4:0 ~ 4:1，限制在掺杂材料的固溶度内。
进一步，所述步骤3中力学性能测试方法为：将块体材料置于微米/纳米压痕设备的测试平台上，施加的压力为：0.1~10 N，分别得到被测试块体材料的硬度，断裂韧性和杨氏模量，然后将被测试块体材料进行脱锂处理，当脱出50% 锂时，被测试材料的硬度﹑断裂韧性和杨氏模量下降在20%内的，即为最优材料。
进一步，该方法还包括以下步骤，当两种块体材料的硬度﹑断裂韧性和杨氏模量下降值都在20%内时，通过测试两种块体材料的导电性能，将块体材料两面镀金，利用交流阻抗谱仪和直流电阻仪测量离子电导和电子电导，得到块体材料的电导率，选择电导率高的块体材料为最优材料。
本发明的优点在于结合力学和电学性能测试作为选择依据，相对传统试错法大大提高了效率，并且更加具有针对性，所制备材料循环性能较原基体材料有了大幅度提高。
附图说明
图1为传统锂离子电池表面材料选择与制作过程
图2为本工艺锂离子电池表面材料选择与制作过程
图3为表面修饰层效果示意图。
图4为包覆后颗粒。
图5为该基体循环性能。
图6 NCA-Ti20与NCA、NCA-Ti10(Li(Ni0.8CO0.15Al0.05)0.9Ti0.1O2)力学性能对比。
具体实施方式
下面结合具体实施例对本发明的技术方案作进一步说明，但本方法并不局限于以下实施例。
本发明一种锂电电极材料表面固溶层材料的优化方法，该方法具体包括以下步骤：
步骤1：按照设计成分，将基体材料与掺杂材料在一定范围内按照不同的比例分别进行混合；
步骤2：将不同比例的混合材料分别制成块体材料；
步骤3：分别测试步骤2得到的块体材料的力学性能，以力学性能判定依据选出不同成分的块体材料中筛选出最优组分，将最优材料包覆于电极材料表面获得改性电极材料。
进一步，所述步骤1中比例为4:0 ~ 4:1，限制在掺杂材料的固溶度内。
进一步所述步骤3中力学性能测试方法为：将块体材料置于微米/纳米压痕设备的测试平台上，施加的压力为：0.1~10 N，分别得到被测试块体材料的硬度，断裂韧性和杨氏模量，然后将被测试块体材料进行脱锂处理，当脱出50% 锂时，被测试材料的硬度﹑断裂韧性和杨氏模量下降在20%内的，即为最优材料。
该方法还包括以下步骤，当两种块体材料的硬度﹑断裂韧性和杨氏模量下降值都在20%内时，通过测试两种块体材料的导电性能，将块体材料两面镀金，利用交流阻抗谱仪和直流电阻仪测量离子电导和电子电导，得到块体材料的电导率，选择电导率高的块体材料为最优材料。
实施例1：
1) 将基体材料(LiNi0.8CO0.15Al0.05O2)与掺杂材料分别以摩尔比9:1，4:1比例混合，其中掺杂材料为纳米级TiO2与Li2CO3其摩尔比为1:1~1:1.1。
2) 将混合物于碳酸锂分解温度上到材料熔点下温度区间内进行初烧，较优为650℃~800℃下保温6~8小时，使其发生充分反应。
3) 将初烧产物再次粉碎后压制，以高于初烧温度进行烧结，从而使晶粒充分生长但不宜过高以防止出现晶粒异常长大，从而导致块体烧结不均匀，较优区段为700~1000℃，保温8~12小时烧获得目标产物NCA-Ti10，NCA-Ti20
4) 对NCA，NCA-Ti10，NCA-Ti20进行力学性能与电学性能测试，这三种材料力学性能和电导性能较优的为NCA-Ti20，故确定NCA-Ti20为最优包覆材料
5) 将NCA-Ti20包覆于NCA颗粒表层后即获得改性NCA正极材料。
其表面修饰层效果示意图如图3。
包覆后颗粒（d、e、f）与包覆前颗粒（a、b、c）SEM对比照片如图4。
该包覆材料循环性能如图5。
NCA-Ti20与NCA、NCA-Ti10力学性能对比为图6。

Claims (3)

1.一种锂电电极材料表面固溶层材料的优化方法，其特征在于，该方法具体包括以下步骤：
步骤1：按照设计成分，将含锂的基体材料与含锂的掺杂材料在一定范围内按照不同的比例分别进行混合；
步骤2：将步骤1混合后的不同比例的混合材料分别制成块体材料；
步骤3：分别测试步骤2得到的块体材料的力学性能，以力学性能判定依据选出不同成分的块体材料中筛选出最优材料的组分，将最优材料包覆于电极材料表面获得改性电极材料；
所述步骤3中力学性能测试方法为：将块体材料置于微米/纳米压痕设备的测试平台上，施加的压力为：0.1~10 N，分别得到被测试块体材料的硬度，断裂韧性和杨氏模量，然后将被测试块体材料进行脱锂处理，当脱出50% 锂时，被测试材料的硬度﹑断裂韧性和杨氏模量下降在20%内的，即为最优材料。
2.根据权利要求1所述的方法，其特征在于，所述步骤1中的含锂的基体材料与含锂的掺杂材料的摩尔比为4:0 ~ 4:1，限制在掺杂材料的固溶度内。
3.根据权利要求1所述的方法，其特征在于，该方法还包括以下步骤，当两种块体材料的硬度﹑断裂韧性和杨氏模量下降值都在20%内时，通过测试两种块体材料的导电性能，将块体材料两面镀金，利用交流阻抗谱仪和直流电阻仪测量离子电导和电子电导，得到块体材料的电导率，选择电导率高的块体材料为最优材料。
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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103633314A (zh) * 2013-10-28 2014-03-12 江苏金和源新材料有限公司 一种复合改性锂离子电池用的正极材料锰酸锂制备方法
CN105470455A (zh) * 2014-09-03 2016-04-06 中国科学院宁波材料技术与工程研究所 一种改性锂离子电池正极材料及其制备方法

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103633314A (zh) * 2013-10-28 2014-03-12 江苏金和源新材料有限公司 一种复合改性锂离子电池用的正极材料锰酸锂制备方法
CN105470455A (zh) * 2014-09-03 2016-04-06 中国科学院宁波材料技术与工程研究所 一种改性锂离子电池正极材料及其制备方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Charge–discharge properties of surface-modified carbon by resin coating in Li-ion battery;J.-S.Kim，et al.;《Journal of Power Sources》;20020126;标题、第178页右栏倒数第1段-第179页左栏第1段 *

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