CN102620993A - Battery pole piece flexibility characterization method and flexibility testing device - Google Patents
Battery pole piece flexibility characterization method and flexibility testing device Download PDFInfo
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Abstract
本发明公开了一种电池极片柔韧度表征方法,其包括以下步骤:(1)将电池极片裁剪为一定尺寸的矩形,并卷成单层圆柱面;(2)从与电池极片圆柱面垂直的方向,匀速地对圆柱面施加压力使之发生固定的椭圆形变;(3)在形变过程中,检测圆柱极片左右两端的切应力和上下两端的相应位移,得到切应力-位移曲线;(4)分析处理切应力-位移曲线,得出电池极片的柔韧度表征量。与现有技术相比,本发明电池极片柔韧度表征方法能快速定量地测试出电池极片的柔韧度,且测试精度大大提高。此外,本发明还公开了一种电池极片柔韧度测试装置。
The invention discloses a method for characterizing the flexibility of a battery pole piece, which comprises the following steps: (1) cutting the battery pole piece into a rectangle of a certain size, and rolling it into a single-layer cylindrical surface; (3) During the deformation process, detect the shear stress at the left and right ends of the cylindrical pole piece and the corresponding displacement at the upper and lower ends, and obtain the shear stress-displacement curve (4) Analyzing and processing the shear stress-displacement curve to obtain the characterization of the flexibility of the battery pole piece. Compared with the prior art, the battery pole piece flexibility characterization method of the present invention can quickly and quantitatively test the flexibility of the battery pole piece, and the test accuracy is greatly improved. In addition, the invention also discloses a device for testing the flexibility of battery pole pieces.
Description
技术领域 technical field
本发明涉及膜片力学性能测试领域,更具体地说,本发明涉及一种电池极片柔韧度表征方法及相关的柔韧度测试装置。The invention relates to the field of testing the mechanical properties of diaphragms, and more specifically, the invention relates to a method for characterizing the flexibility of a battery pole piece and a related flexibility testing device.
背景技术 Background technique
随着现代社会的发展和环保意识的增强,越来越多的设备选择以可充电二次电池作为电源,如手机、笔记本电脑、电动工具、电动汽车等等,这为可充电二次电池的应用与发展提供了广阔的空间,同时也对二次电池提出了更高的要求,希望其能够具有更高的容量、良好的安全性以及较长的循环寿命等。With the development of modern society and the enhancement of environmental awareness, more and more devices choose to use rechargeable secondary batteries as power sources, such as mobile phones, notebook computers, power tools, electric vehicles, etc. Application and development provide a broad space, but also put forward higher requirements for secondary batteries, hoping that they can have higher capacity, good safety and longer cycle life.
但是,高容量要求电池极片具有更高的涂布重量和压实密度,这都使得电池极片的柔韧度变差,尤其是正极片。在方形电芯极片的卷绕过程中,特别是正极片弯折时,卷心两侧受到的挤压切应力和外部受到的拉升切应力最大,导致膜片容易在卷绕两侧发生断裂;而在圆柱形电芯卷绕时,卷绕内圈的极片打皱程度也和极片的柔韧度有很大关系。在具有卷绕结构的方形电芯的整形过程中,电芯受到来自外部的压力,卷绕两端的电芯极片产生的形变和切应力最大,极易发生断裂。可见,柔韧度差的极片,一方面影响卷绕工序的优率,导致经济损失,另一方面容易断裂而出现铝箔毛刺、膜片掉粉,以致影响电芯的K值甚至安全性能。However, high capacity requires higher coating weight and compaction density of the battery pole piece, which makes the flexibility of the battery pole piece worse, especially the positive pole piece. During the winding process of the square cell pole piece, especially when the positive pole piece is bent, the extruding shear stress on both sides of the winding core and the pulling shear stress on the outside are the largest, which makes the diaphragm easy to occur on both sides of the winding. fracture; and when the cylindrical battery core is wound, the degree of wrinkling of the pole piece wound on the inner ring also has a great relationship with the flexibility of the pole piece. During the shaping process of the square cell with winding structure, the cell is subjected to external pressure, and the deformation and shear stress of the cell pole pieces at both ends of the winding are the largest, and it is easy to break. It can be seen that pole pieces with poor flexibility, on the one hand, affect the efficiency of the winding process, resulting in economic losses;
目前,对电池极片的柔韧度表征主要有两种方法,方法之一是用不同直径的卷轴来卷绕极片,再通过肉眼辨别极片的打皱程度;方法之二是将电池极片对折后进行拉伸,并对着灯光看是否有裂口。这两种方法都在较大程度上依赖人的主观判断,精度有限,对于柔韧度差别小的极片不能进行有效的区别,也不能对极片柔韧度进行定量表征。At present, there are mainly two methods to characterize the flexibility of the battery pole piece. One method is to wind the pole piece with reels of different diameters, and then distinguish the degree of wrinkling of the pole piece with the naked eye; the second method is to wrap the battery pole piece Stretch it after folding it in half and hold it up to the light to see if there are any cracks. These two methods rely on human subjective judgment to a large extent, and have limited accuracy. They cannot effectively distinguish pole pieces with small differences in flexibility, nor can they quantitatively characterize the flexibility of pole pieces.
有鉴于此,确有必要开发一种精度较高的电池极片柔韧度表征方法及柔韧度测试装置。In view of this, it is indeed necessary to develop a high-precision battery pole piece flexibility characterization method and flexibility testing device.
发明内容 Contents of the invention
本发明的目的在于:提供一种精度较高的电池极片柔韧度表征方法及柔韧度测试装置,以对电芯极片的柔韧度进行定量表征。The purpose of the present invention is to provide a high-precision battery pole piece flexibility characterization method and a flexibility testing device, so as to quantitatively characterize the flexibility of the battery pole piece.
为了实现上述发明目的,本发明提供了一种电池极片柔韧度表征方法,其包括以下步骤:(1)将电池极片裁剪为一定尺寸的矩形,并卷成单层圆柱面;(2)从与电池极片圆柱面垂直的方向,匀速地对圆柱面施加压力使之发生固定的椭圆形变;(3)在形变过程中,检测圆柱极片左右两端的切应力和上下两端的相应位移,得到切应力-位移曲线;(4)分析处理切应力-位移曲线,得出电池极片的柔韧度表征量。In order to achieve the purpose of the above invention, the present invention provides a method for characterizing the flexibility of a battery pole piece, which includes the following steps: (1) cutting the battery pole piece into a rectangle of a certain size, and rolling it into a single-layer cylindrical surface; (2) From the direction perpendicular to the cylindrical surface of the battery pole piece, apply pressure to the cylindrical surface at a uniform speed to cause a fixed elliptical deformation; (3) During the deformation process, detect the shear stress at the left and right ends of the cylindrical pole piece and the corresponding displacement at the upper and lower ends, Obtain the shear stress-displacement curve; (4) analyze and process the shear stress-displacement curve to obtain the characterization of the flexibility of the battery pole piece.
作为本发明电池极片柔韧度表征方法的一种改进,所述步骤(4)中采用的分析处理方法为:以所述电池极片圆柱面发生固定形变时左右两端所对应的切应力来表征极片的柔韧度。As an improvement of the battery pole piece flexibility characterization method of the present invention, the analysis and processing method adopted in the step (4) is: the shear stress corresponding to the left and right ends when the cylindrical surface of the battery pole piece undergoes fixed deformation Characterizes the flexibility of the pole piece.
作为本发明电池极片柔韧度表征方法的一种改进,所述步骤(4)中采用的分析处理方法为:以所述切应力-位移曲线的平均斜率来表征极片的柔韧度。As an improvement of the method for characterizing the flexibility of the battery pole piece of the present invention, the analysis and processing method adopted in the step (4) is: the flexibility of the pole piece is characterized by the average slope of the shear stress-displacement curve.
作为本发明电池极片柔韧度表征方法的一种改进,所述步骤(1)中裁剪得到的矩形极片尺寸为:宽度30-40毫米,长度100-110毫米。As an improvement to the method for characterizing the flexibility of the battery pole piece of the present invention, the rectangular pole piece cut out in the step (1) has a size of 30-40 mm in width and 100-110 mm in length.
作为本发明电池极片柔韧度表征方法的一种改进,所述步骤(2)中是以小于2mm/s的速度对极片的圆柱面施加压力的。As an improvement of the method for characterizing the flexibility of the battery pole piece of the present invention, in the step (2), pressure is applied to the cylindrical surface of the pole piece at a speed of less than 2mm/s.
为了实现上述发明目的,本发明还提拱了一种电池极片柔韧度测试装置,其包括动态加载机构、动态信号采集单元、动态信号传递单元和数据处理单元,动态加载机构包括主机架、低速气缸、平行压板和样品平台,低速气缸和样品平台固定在主机架上,待测试极片固定在样品平台上,平行压板固定在低速气缸上对待测试极片起加载施压作用,低速气缸、平行压板和样品平台在空间上垂直对应,动态信号采集单元和动态加载机构机械连接,动态信号采集单元、动态信号传递单元、数据处理单元依次通过信号连接。In order to achieve the purpose of the above invention, the present invention also proposes a battery pole piece flexibility testing device, which includes a dynamic loading mechanism, a dynamic signal acquisition unit, a dynamic signal transmission unit, and a data processing unit. The dynamic loading mechanism includes a main frame, a low-speed Cylinder, parallel platen and sample platform. The low-speed cylinder and sample platform are fixed on the main frame. The pole piece to be tested is fixed on the sample platform. The pressure plate and the sample platform are vertically corresponding in space, the dynamic signal acquisition unit is mechanically connected with the dynamic loading mechanism, and the dynamic signal acquisition unit, the dynamic signal transmission unit and the data processing unit are sequentially connected through signals.
作为本发明电池极片柔韧度测试装置的一种改进,所述样品平台的中心线上设置有两个凸起的长方形定位珊和两个平行于平台的磁铁,一个专用于固定电池极片的固定卡扣上开设有两个长方形的穿孔,固定卡扣通过磁铁定位于样品平台上。As an improvement of the battery pole piece flexibility testing device of the present invention, two raised rectangular positioning bars and two magnets parallel to the platform are arranged on the center line of the sample platform, and one is dedicated to fixing the battery pole piece. The fixing buckle is provided with two rectangular perforations, and the fixing buckle is positioned on the sample platform through a magnet.
作为本发明电池极片柔韧度测试装置的一种改进,所述动态信号采集单元包括光纤位移传感器和动态载荷传感器,光纤位移传感器设于平行压板上,用于检测平行压板在垂直方向上的位移变化量,动态载荷传感器设于样品平台的下面,用于检测圆柱面极片两端所受到的切应力。As an improvement of the battery pole piece flexibility testing device of the present invention, the dynamic signal acquisition unit includes an optical fiber displacement sensor and a dynamic load sensor, and the optical fiber displacement sensor is arranged on the parallel platen to detect the displacement of the parallel platen in the vertical direction The dynamic load sensor is set under the sample platform to detect the shear stress on both ends of the cylindrical pole piece.
作为本发明电池极片柔韧度测试装置的一种改进,所述动态信号传递单元是一个电磁信号转换器,其与光纤位移传感器、动态载荷传感器及数据处理单元分别建立电信号连接,可将光纤位移传感器、动态载荷传感器采集到的电磁信号转换成可供数据处理单元识别处理的信号并将其传送给数据处理单元,数据处理单元把从动态信号传递单元接收到的位移、切应力信号制作成切应力-位移曲线。As an improvement of the battery pole piece flexibility testing device of the present invention, the dynamic signal transmission unit is an electromagnetic signal converter, which establishes electrical signal connections with the optical fiber displacement sensor, dynamic load sensor and data processing unit respectively, and can connect the optical fiber The electromagnetic signals collected by the displacement sensor and the dynamic load sensor are converted into signals that can be recognized and processed by the data processing unit and transmitted to the data processing unit. The data processing unit makes the displacement and shear stress signals received from the dynamic signal transmission unit into Shear stress-displacement curve.
作为本发明电池极片柔韧度测试装置的一种改进,所述动态加载机构中的平行压板下压到底部后与样品平台之间的间距为8~16毫米。As an improvement of the battery pole piece flexibility testing device of the present invention, the distance between the parallel platen in the dynamic loading mechanism and the sample platform after being pressed down to the bottom is 8-16 mm.
与现有技术相比,本发明电池极片柔韧度表征方法能快速定量地测试出电池极片的柔韧度,且测试精度大大提高。Compared with the prior art, the battery pole piece flexibility characterization method of the present invention can quickly and quantitatively test the flexibility of the battery pole piece, and the test accuracy is greatly improved.
附图说明 Description of drawings
下面结合附图和具体实施方式,对本发明电池极片柔韧度表征方法、测试装置及其有益技术效果进行详细说明。The method for characterizing the flexibility of the battery pole piece, the testing device and its beneficial technical effects of the present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.
图1为本发明电池极片柔韧度测试装置的结构示意图。FIG. 1 is a schematic structural diagram of a battery pole sheet flexibility testing device of the present invention.
图2为本发明电池极片柔韧度测试装置的样品平台结构示意图。Fig. 2 is a schematic diagram of the sample platform structure of the battery pole piece flexibility testing device of the present invention.
图3为使用本发明电池极片柔韧度表征方法和测试装置测试前的电池极片受力分析图。Fig. 3 is a force analysis diagram of the battery pole piece before testing using the battery pole piece flexibility characterization method and testing device of the present invention.
图4为使用本发明电池极片柔韧度表征方法和测试装置测试时的电池极片受力分析图。Fig. 4 is a force analysis diagram of the battery pole piece when tested using the battery pole piece flexibility characterization method and testing device of the present invention.
图5为使用本发明测得的压实密度对正极片柔韧度影响的位移-切应力曲线图。Fig. 5 is a displacement-shear stress curve diagram of the influence of the compacted density on the flexibility of the positive electrode sheet measured by the present invention.
具体实施方式 Detailed ways
本发明电池极片柔韧度表征方法通过将电池极片卷成单层圆柱面,再匀速地对其圆柱面施加压力使之发生固定的椭圆形变,并通过对整个形变过程进行受力分析来反映电池极片卷绕后在压力下的柔韧性。The battery pole piece flexibility characterization method of the present invention rolls the battery pole piece into a single-layer cylindrical surface, then applies pressure to the cylindrical surface at a uniform speed to cause a fixed elliptical deformation, and reflects the force analysis of the entire deformation process. The flexibility of the battery pole piece under pressure after winding.
请参阅图1和图2,为了实现上述方法,本发明提供了一种电池极片柔韧度测试装置,其包括动态加载机构、动态信号采集单元、动态信号传递单元30和数据处理单元40。动态加载机构和动态信号采集单元机械连接,动态信号采集单元、动态信号传递单元30、数据处理单元40依次通过信号连接。Please refer to FIG. 1 and FIG. 2 , in order to realize the above method, the present invention provides a battery pole piece flexibility testing device, which includes a dynamic loading mechanism, a dynamic signal acquisition unit, a dynamic
动态加载机构包括主机架12、低速气缸14、平行压板16和样品平台18。其中,低速气缸14固定在主机架12的顶部,平行压板16固定在低速气缸14的下部,样品平台18固定在主机架12的底部且位于平行压板16之下,低速气缸14、平行压板16和样品平台18在空间上垂直对应。样品平台18的中心线上设置有两个凸起的长方形定位珊180和两个平行于平台的磁铁182,一个专用于固定圆柱面极片60的固定卡扣184上开设有两个长方形的穿孔,固定卡扣184通过磁铁182定位于样品平台18上。低速气缸14的上面与气压表连接,动作则通过精密调压阀控制,其下的平行压板16用于对样品平台18上的圆柱面极片60进行加载施压。The dynamic loading mechanism includes a main frame 12 , a low-
动态信号采集单元包括光纤位移传感器22和动态载荷传感器24。光纤位移传感器22设于平行压板16上,用于检测平行压板16在垂直方向上的位移变化量。动态载荷传感器24设于样品平台18的下面,用于检测圆柱面极片60两端所受到的切应力。The dynamic signal acquisition unit includes an optical
动态信号传递单元30是一个电磁信号转换器,其与光纤位移传感器22、动态载荷传感器24及数据处理单元40分别建立电信号连接,从而将光纤位移传感器22、动态载荷传感器24采集到的电磁信号转换成可供数据处理单元40识别处理的信号并将其传送给数据处理单元40。The dynamic
数据处理单元40是一台计算机,它的数据处理模块可以把从动态信号传递单元30接收到的位移、切应力信号制作成切应力-位移曲线。The
以下将对本发明的原理进行详细说明。The principle of the present invention will be described in detail below.
请参阅图3,当把圆柱面极片60固定在样品平台18上开始测试前,圆柱面极片60在垂直方向仅受到自身重力mg和样品平台的支持力N0。这两个力是平衡力,也就是mg=N0,此时样品平台18下面的动态载荷传感器24可以感受到极片对样品平台18的压力F′=N0=mg。测试开始时,通过对动态载荷传感器24采集的压力进行清零,即可以测试到圆柱面极片60在受力形变过程中对样品平台18增加的压力。Please refer to FIG. 3 , before the
请参阅图4,圆柱面极片60在平行压板16施加的垂直载荷下形变成椭圆形,其在垂直方向上受到一对平衡力的作用,即向下的载荷F和向上的支持力N。由于椭圆形极片60是对称结构,现取其上半部分进行受力分析:如图4所示,在垂直方向上椭圆形极片60受到垂直向下的载荷F,在椭圆长轴两端则受到2个垂直向上的切应力f。在形变过程中,样品平台18下面的动态载荷传感器24采集到的压力F′和其对极片的支持力N是一对作用力与反作用力,F′=N=F=2f,因此传感器采集到的力F′能反映弯曲极片椭圆两端受到的切应力大小。由于复杂切应力状态理论解不存在,现假设极片为线弹性体。Please refer to Fig. 4, the
由椭圆周长公式可得:From the formula for the perimeter of an ellipse:
dl=(4dux-2πdu′)----(1);dl=(4du x -2πdu')----(1);
由Hook定律可得:According to Hook's law:
由虚功原理可得:According to the principle of virtual work:
Fdu′=k(l-l0)(4dux-2πdu′)----(3);Fdu'=k(ll 0 )(4du x -2πdu')----(3);
由公式(1)至(3)即可得到压力与位移的关系式:The relationship between pressure and displacement can be obtained from formulas (1) to (3):
F=12ku′----(4);F=12ku'----(4);
其中,公式(4)中的k=ES/l0,E为弹性模量,表征材料抵抗弹性应变的能力,其值越低越容易发生弹性形变,说明柔韧度越好;S为极片60的截面积;l0为圆柱极片60初始圆周长度。可见,在极片60截面积以及长度固定的情况下,压力F与位移u′的比值与材料的弹性模量成正比,即:F/u′~E。由于F′=N=F=2f,因此F′/u′~E,也就是说,圆柱面极片60在施加载荷的平行压板16下发生固定的形变时,动态载荷传感器24收集到的F′值能反映极片的柔韧度:F′越大,说明反映极片材质的弹性模量E就越大,其抵抗弹性应变的能力就越高,就越难发生弹性形变,即柔韧度越差,因此,F′可以对圆柱面极片发生形变时两侧的切应力f进行定量表征。Among them, k=ES/l 0 in the formula (4), E is the elastic modulus, which characterizes the ability of the material to resist elastic strain, the lower the value, the easier it is to undergo elastic deformation, indicating the better the flexibility; S is the
由于极片材料是由箔材作为支撑体,与表面的粉体和胶体经压实后共同形成的复杂材料,类似于钢筋混凝土结构,其材料的弹性模量E的大小与极片材料(配方)、压实密度、涂布重量等相关。由于极片压实密度、涂布重量引起的极片截面积S的变化量相对于极片弹性模量E的变化量很小,因此可以认为极片的切应力f仅与弹性模量E有关,由此可以定量表征不同配方、压实密度、涂布重量的极片的柔韧程度。Since the pole piece material is a complex material formed by compacting the powder and colloid on the surface with the foil as a support, it is similar to a reinforced concrete structure, and the elastic modulus E of the material is the same as the pole piece material (formula ), compaction density, coating weight, etc. Due to the change in the cross-sectional area S of the pole piece caused by the compaction density and coating weight of the pole piece relative to the change in the elastic modulus E of the pole piece is very small, it can be considered that the shear stress f of the pole piece is only related to the elastic modulus E , so that the degree of flexibility of pole pieces with different formulations, compacted densities, and coating weights can be quantitatively characterized.
复杂材料在加载速率等条件下其切应力与应变量不符合直线关系,即E在不断地加载过程中是变化的,E增加的越快,表明材料在加载过程中抵抗弹性应变的能力越强,越不容易发生弹性形变,其柔韧度就越差。因此,可以利用极片切应力在加载过程中随位移的变化趋势来判断极片的柔韧程度。The shear stress and strain of complex materials do not conform to a linear relationship under conditions such as loading rate, that is, E changes during continuous loading, and the faster E increases, the stronger the material's ability to resist elastic strain during loading , the less prone to elastic deformation, the worse its flexibility. Therefore, the flexibility of the pole piece can be judged by the change trend of the shear stress of the pole piece with the displacement during the loading process.
为了保证测量结果的准确性,以下将对本发明相关的主要参数进行分析和设定。In order to ensure the accuracy of the measurement results, the main parameters related to the present invention will be analyzed and set below.
使用本发明电池极片柔韧度测试装置测试电池极片60的柔韧度时,低速气缸14启动时有5mm的加速过程,启动后的运行速度应当小于2mm/s,优选为0.5mm/s,这是为了保证平行压板16的运动速度小于2mm/s,以防止由于平行压板16速度快而影响测试结果,增加极片切应力。平行压板16的运动速度对位置应力测试结果的影响请参见表1。When using the battery pole piece flexibility testing device of the present invention to test the flexibility of the
表1、平行压板的运动速度对位置应力测试结果的影响数据Table 1. Data on the influence of the moving speed of the parallel platen on the position stress test results
平行压板16固定在低速气缸14的下部,其下压到底部后与样品平台18的距离可以通过在平行压板16和低速气缸14的连杆间安装不同高度的钢圈来实现,变换钢圈高度可以实现对圆柱面极片60进行不同程度的变形。请参阅表2所示的平行压板16最低点和样品平台18的间距对测试误差的影响数据,为了保证测试误差小于5%,平行压板16下压到底部后和样品平台18的间距应在8-16mm内,后续实施例使用的间距为13mm。The
表2、平行压板和样品平台的间距对测试误差的影响数据Table 2. Data on the influence of the distance between the parallel platen and the sample platform on the test error
请参阅表3所示的电池极片尺寸及其对应的切应力测试结果,对于相同宽度的极片,极片越长,其绕成的圆柱面的直径就越大。当不同直径的圆柱面受到平行压板16在垂直方向的力而发生一定形变时,直径大的圆柱面相对于直径小的圆柱面发生形变更大,其切应力也更大,如30mm的负极极片,从90mm到110mm的长度范围内,其切应力值随着极片长度的增加而增加。但是,随着极片长度持续增加,其绕成圆柱面受到自身重力的影响加大,在未受到平行压板16的垂直压力前,绕成的圆柱面却呈现出椭圆形。在此状态下,椭圆形极片已受到的切应力被测试时归零处理,导致最后测得的切应力值低于最终形变的真实值,如宽为30mm的极片,长度增加到120mm时,其测试结果反而减小。因此,既要保证被测试极片60足够长以保证测试结果够大,又要保证被测极片60卷绕时不出现椭圆形而保证测试的准确性,需规定被测极片60的长度。根据表3所示的电池极片尺寸及其对应的切应力测试结果,长方形电池极片的裁剪尺寸为长100~110mm具有准确且稳定的测试结果。当极片宽度为30~50mm,带两孔的卡扣184能完好的固定卷绕极片。Please refer to the battery pole piece dimensions and their corresponding shear stress test results shown in Table 3. For pole pieces of the same width, the longer the pole piece, the larger the diameter of the cylindrical surface it is wound into. When the cylindrical surfaces of different diameters are deformed by the force of the
表3、电池极片尺寸及其对应的切应力测试结果Table 3. Dimensions of battery pole pieces and their corresponding shear stress test results
以下为使用本发明的表征方法和测试装置进行电池极片柔韧度测量的实施例。The following is an example of using the characterization method and testing device of the present invention to measure the flexibility of battery pole pieces.
为节约材料,本实施例使用长100mm、宽30mm的电池极片。样品平台18中心线上的两个定位珊180之间距为20mm,两定位珊180长宽高分别为20mm、3mm、2mm。圆形磁铁182位于定位珊180的两端并嵌入样品台18中,其上表面与样品平台18平齐;电池极片60的两端分别以两定位珊180为圆柱面切线,绕成以样品平台18为切面的圆柱面。将带两孔的卡扣184放在电池极片182上,卡扣184的两孔分别与样品台18上的两定位珊180对应,如图2所示。定位珊180两端的磁铁182能将卡扣184牢牢的吸住,从而很好地固定待测试的电池极片60。In order to save materials, this embodiment uses battery pole pieces with a length of 100 mm and a width of 30 mm. The distance between the two positioning shanks 180 on the center line of the
样品固定后,打开动态加载机构的电源,以及数据处理单元40的位移-力量界面。按下动态加载机构开关的同时点击数据处理单元40的开始键,低速气缸14推动平行压板16向样品平台18上的筒状极片60移动,光纤位移传感器22、动态载荷传感器24分别将实时采集到的信号传递给动态信号传递单元30,动态信号传递单元30将电磁信号转换成可供数据处理单元40识别处理的信号,并将其传递给数据处理单元40。数据处理单元40将信号经过处理而在其位移-力量界面中以图形显示出来,最后形成相应的数据文件。数据文件给出每0.003s采集的位移和切应力,并绘制位移-切应力曲线,该形变过程中的最大切应力作为极片柔韧度的判断依据:极片切应力越大,柔韧度越差,极片越容易脆断。After the sample is fixed, turn on the power of the dynamic loading mechanism and the displacement-force interface of the
对于锂电池极片,通过测试圆柱面极片60发生一定形变后的切应力发现,正极片比负极片的切应力大很多,而且切应力随着压板位移的变化增加趋势更加明显,说明正极片的弹性模量要比负极片的弹性模量大,其抗弹性形变的能力更强,更不容易发生弹性形变,柔韧度也更差。这也与在裸电芯卷绕和电芯整形工序中,正极片比负极片更容易断裂的事实相符合。For the lithium battery pole piece, by testing the shear stress of the cylindrical
请参阅图5,对于涂布重量、配方种类都相同的正极片,测得结果显示:随着极片压实密度增大,极片产生固定形变所对应的切应力也增大,这说明压实密度越大导致极片的弹性模量E越大,其抗弹性形变的能力越强,越难发生弹性形变,则极片的柔韧度就越差,也越容易断裂。同时,由图5也可以看出,在圆柱面极片受载荷形成椭圆形极片的整个过程中,切应力也随压板的位移而增加,随着极片压实密度的提高,极片切应力增加的趋势就越明显,则弹性模量E在加载过程中增加的趋势越明显,其抗弹性形变的能力越强,越难发生弹性形变,则极片的柔韧度就越差,也越容易断裂。Please refer to Figure 5. For the positive electrode sheets with the same coating weight and formula, the measured results show that as the compaction density of the electrode sheet increases, the shear stress corresponding to the fixed deformation of the electrode sheet also increases, which shows that the compression The greater the solid density, the greater the elastic modulus E of the pole piece, the stronger its ability to resist elastic deformation, the harder it is to elastically deform, the worse the flexibility of the pole piece, and the easier it is to break. At the same time, it can also be seen from Figure 5 that during the entire process of forming an elliptical pole piece under load on the cylindrical surface, the shear stress also increases with the displacement of the pressure plate. The more obvious the stress increases, the more obvious the elastic modulus E increases during the loading process, the stronger its ability to resist elastic deformation, the harder it is to elastically deform, the worse the flexibility of the pole piece, and the more easy to break.
综上所述,本发明能够定量地测出电池圆柱面极片60发生固定形变时极片两端所对应的切应力大小,该力和极片60的弹性模量E正相关,弹性模量E是表征材料抗弹性形变的能力,能力越强就越难发生弹性形变,就越容易脆断,柔韧度就越差,由此结果来判断极片的柔韧度程度。同时也可以根据极片形变时切应力随位移的变化趋势来判断其柔韧度,即随着平行压板位移的增加,不同极片切应力随之增加的程度,也就是弹性模量E随平行压板位移的增加程度,E增加的越明显,说明其抗弹性形变的能力越强,越难发生弹性形变,柔韧度也越差。本发明测试装置具有很好的分辨率0.1gf,对极片切应力的测试结果具有良好的区分度和重现性。本发明测试装置的结构简单,对于电池正负极片以及其他的涂膜结构、塑料膜片均适用,尤其适用于具有卷绕结构的电池极片柔韧度测试,如锂离子电池极片、镍氢电池极片、镍镉电池极片的柔韧度的测试,可用作不同品种电池极片柔韧度的监测,为自动卷绕的张力和整形压力调节提供参考,也可以为配方的研发、冷压参数的选择提供依据,有效防止极片卷绕的脆断。In summary, the present invention can quantitatively measure the magnitude of the shear stress corresponding to both ends of the pole piece when the cylindrical
根据上述说明书的揭示和教导,本发明所属领域的技术人员还可以对上述实施方式进行适当的变更和修改。因此,本发明并不局限于上面揭示和描述的具体实施方式,对本发明的一些修改和变更也应当落入本发明的权利要求的保护范围内。此外,尽管本说明书中使用了一些特定的术语,但这些术语只是为了方便说明,并不对本发明构成任何限制。According to the disclosure and teaching of the above specification, those skilled in the art to which the present invention pertains can also make appropriate changes and modifications to the above embodiment. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the present invention should also fall within the protection scope of the claims of the present invention. In addition, although some specific terms are used in this specification, these terms are only for convenience of description and do not constitute any limitation to the present invention.
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Cited By (12)
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Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20090049923A1 (en) * | 2007-03-13 | 2009-02-26 | Michael Rogers | Method and Device for Controlled Compression Bat Rolling and a Composite Bat Barrel Broken-In By Such Method |
KR20090090099A (en) * | 2008-02-20 | 2009-08-25 | 엘에스전선 주식회사 | Flexibility measuring device |
CN101706375A (en) * | 2009-01-20 | 2010-05-12 | 海洋王照明科技股份有限公司 | Battery extrusion test device |
CN102095637A (en) * | 2010-11-12 | 2011-06-15 | 中国建筑材料检验认证中心有限公司 | Method for assessing elastic modulus and strength of circular or circular-tube brittle material |
-
2012
- 2012-04-16 CN CN201210111542.7A patent/CN102620993B/en active Active
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20090049923A1 (en) * | 2007-03-13 | 2009-02-26 | Michael Rogers | Method and Device for Controlled Compression Bat Rolling and a Composite Bat Barrel Broken-In By Such Method |
KR20090090099A (en) * | 2008-02-20 | 2009-08-25 | 엘에스전선 주식회사 | Flexibility measuring device |
CN101706375A (en) * | 2009-01-20 | 2010-05-12 | 海洋王照明科技股份有限公司 | Battery extrusion test device |
CN102095637A (en) * | 2010-11-12 | 2011-06-15 | 中国建筑材料检验认证中心有限公司 | Method for assessing elastic modulus and strength of circular or circular-tube brittle material |
Cited By (18)
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CN107290228B (en) * | 2017-06-15 | 2023-08-25 | 力神(青岛)新能源有限公司 | Lithium ion battery pole piece flexibility testing device |
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