阅读说明：本技术 一种锂离子软包电池平整度测量装置及测量方法 (Flatness measuring device and method for lithium ion soft package battery ) 是由 张翮辉 常春平 游浩林 于 2020-12-14 设计创作，主要内容包括：本发明提供了一种锂离子软包电池平整度测量装置,包括由多个相同的测量杆(2)组成的矩阵阵列、基座(3)和采集卡(4)；所述测量杆(2)处于竖直状态,包括测量探头(21)、支撑杆(22)和信号线(23)；所述信号线(23)的上下两端分别于和采集卡(4)电性连接；所述测量探头(21)由压电陶瓷制成且顶端为水平平面。本发明还提供了一种锂离子软包电池平整度测量方法,将被测的锂离子软包电池平放于测量杆(2)组成的矩阵阵列之上,读取各测量杆(2)测得的压力值构成压力值矩阵,计算并输出平整度系数。本发明提供的测量装置结构简单、易于制作、精度较高,对应的测量方法操作简便、科学合理且稳定性好。(The invention provides a flatness measuring device for a lithium ion soft package battery, which comprises a matrix array, a base (3) and a collecting card (4), wherein the matrix array is composed of a plurality of same measuring rods (2); the measuring rod (2) is in a vertical state and comprises a measuring probe (21), a supporting rod (22) and a signal line (23); the upper end and the lower end of the signal wire (23) are respectively and electrically connected with the acquisition card (4); the measuring probe (21) is made of piezoelectric ceramics, and the top end of the measuring probe is a horizontal plane. The invention also provides a flatness measuring method of the lithium ion soft package battery, which comprises the steps of placing the lithium ion soft package battery to be measured on a matrix array formed by the measuring rods (2), reading pressure values measured by the measuring rods (2) to form a pressure value matrix, and calculating and outputting a flatness coefficient. The measuring device provided by the invention has the advantages of simple structure, easiness in manufacturing, higher precision, simplicity and convenience in operation of the corresponding measuring method, science and reasonability and good stability.)

1. A flatness measuring device for a lithium ion soft package battery is used for flatness measurement of the lithium ion soft package battery (1) and is characterized by comprising a matrix array, a base (3) and a collecting card (4), wherein the matrix array is composed of a plurality of same measuring rods (2); the measuring rod (2) is in a vertical state and comprises a measuring probe (21), a supporting rod (22) and a signal line (23); the upper end and the lower end of the supporting rod (22) are respectively and mechanically connected with the measuring probe (21) and the base (3); the upper end and the lower end of the signal wire (23) are respectively and electrically connected with the acquisition card (4); the supporting rod (22) is of a hollow structure, and a signal wire (23) penetrates through the supporting rod; the measuring probe (21) is made of piezoelectric ceramics, and the top end of the measuring probe is a horizontal plane.

2. The flatness measuring device for the lithium ion soft package battery according to claim 1, wherein the matrix array composed of a plurality of identical measuring rods (2) just covers the measured plane of the lithium ion soft package battery (1), and the distance between two adjacent measuring rods (2) in the same extending direction of the matrix array is equal.

3. The measuring method applied to the flatness measuring device of the lithium ion soft package battery in the claims 1-2 is characterized by comprising the following steps:

s1, placing the lithium ion soft package battery to be tested on a matrix array formed by a plurality of same measuring rods (2);

s2, measuring the pressure value obtained by each measuring probe (21);

s3, reading the pressure values measured by the measuring rods (2) through the acquisition card (4) to form a pressure value matrix, and calculating and outputting a flatness coefficient K:

K＝1-Std/Ave

in the formula, K is the flatness coefficient of the lithium ion soft package battery; std is the standard deviation of all elements in the pressure value matrix; ave is the average of all elements in the pressure value matrix.

Technical Field

The invention relates to the field of lithium ion batteries, in particular to a flatness measuring device and a flatness measuring method for a lithium ion soft package battery.

Background

Lithium ion batteries are widely used in various departments of national economy and in the field of residential life. Among them, the lithium ion soft package battery has been more and more emphasized by people because of its advantages of good safety, light weight, large capacity, small internal resistance, and flexible customization. The lithium ion soft package battery is generally packaged by an aluminum plastic film structurally, and the product of the lithium ion soft package battery requires that the surface of the battery is smooth and has no holes. For example, chinese patent CN201910208796.2 discloses a method for improving the surface flatness of lithium batteries. If the factors such as design defects, poor production process or improper use exist, the flatness of the plane of the lithium ion soft package battery is likely to be reduced, and performance is reduced and even potential safety hazards are brought. Therefore, it is necessary to detect the surface flatness of the lithium ion pouch battery immediately after shipment or after a certain period of use. However, the known technical occasions generally use manual visual inspection or touch and other methods to detect the surface flatness of the lithium ion soft package battery, which depends heavily on the subjective judgment of human and cannot give objective, accurate and quantitative detection results. Therefore, it is urgent to develop an objective, scientific and convenient flatness measuring device and method for a lithium ion soft package battery.

Disclosure of Invention

In order to solve the technical problems, the invention provides a flatness measuring device for a lithium ion soft package battery, which is simple in structure, easy to manufacture and high in precision, and a measuring method thereof.

According to one aspect of the invention, the invention provides a flatness measuring device for a lithium ion soft package battery, which adopts the technical scheme that: a flatness measuring device for a lithium ion soft package battery is used for flatness measurement of the lithium ion soft package battery and comprises a matrix array, a base and an acquisition card, wherein the matrix array is composed of a plurality of same measuring rods; the measuring rod is in a vertical state and comprises a measuring probe, a supporting rod and a signal line; the upper end and the lower end of the supporting rod are respectively and mechanically connected with the measuring probe and the base; the upper end and the lower end of the signal wire are respectively and electrically connected with the acquisition card; the supporting rod is of a hollow structure and a signal wire penetrates through the supporting rod; the measuring probe is made of piezoelectric ceramics and the top end of the measuring probe is a horizontal plane.

According to the flatness measuring device for the lithium ion soft package battery, the matrix array formed by the same measuring rods just covers the measured plane of the lithium ion soft package battery, and the distance between every two adjacent measuring rods in the same extending direction of the matrix array is equal.

According to another aspect of the invention, a measuring method applied to the flatness measuring device for the lithium ion soft package battery is provided, and the technical scheme is divided into the following steps:

s1, placing the lithium ion soft package battery to be tested on a matrix array formed by a plurality of same measuring rods;

s2, measuring the pressure value obtained by each measuring probe;

s3, reading pressure values measured by the measuring rods through an acquisition card to form a pressure value matrix, and calculating and outputting a flatness coefficient K:

K＝1-Std/Ave

in the formula, K is the flatness coefficient of the lithium ion soft package battery; std is the standard deviation of all elements in the pressure value matrix; ave is the average of all elements in the pressure value matrix.

The invention has the beneficial effects that:

1. according to the fact that the mass distribution of the lithium ion soft package battery is approximately equal, the lithium ion soft package battery is placed on each horizontal plane at the top end of the measuring rod matrix array, and pressure data of each position are obtained through the measuring probe made of piezoelectric ceramics. If the surface of the lithium ion soft package battery, which is in contact with the measuring rod, is uneven, the pressure value measured by the measuring rod at the concave part is higher, the pressure value measured by the measuring rod at the convex part is lower, and the standard deviation of all elements in the pressure value matrix formed by the pressure values measured by the measuring rods is larger. Therefore, the flatness measuring method for the lithium ion soft package battery designed according to the characteristics is objective, scientific, simple and feasible, and has good stability of measuring results for the same type of battery.

2. According to the flatness measuring device for the lithium ion soft package battery, the supporting rod is of a hollow structure, the signal wire penetrates through the supporting rod, so that the structure is compact, the supporting rod and the signal wire inside the supporting rod are convenient to check and maintain, and if a problem occurs in a single measuring rod, the single measuring rod is convenient to replace. In addition, the whole flatness measuring device for the lithium ion soft package battery is simple in structure, easy to manufacture and high in precision.

Drawings

Fig. 1 is a schematic structural diagram of a flatness measuring device for a lithium ion soft package battery in an embodiment of the invention.

Fig. 2 is a schematic structural diagram of the measuring rod in fig. 1.

Detailed Description

A flatness measuring device for a lithium ion soft package battery is used for flatness measurement of the lithium ion soft package battery and comprises a matrix array, a base and an acquisition card, wherein the matrix array is composed of a plurality of same measuring rods; the measuring rod is in a vertical state and comprises a measuring probe, a supporting rod and a signal line; the upper end and the lower end of the supporting rod are respectively and mechanically connected with the measuring probe and the base; the upper end and the lower end of the signal wire are respectively and electrically connected with the acquisition card; the supporting rod is of a hollow structure and a signal wire penetrates through the supporting rod; the measuring probe is made of piezoelectric ceramics and the top end of the measuring probe is a horizontal plane.

Further, the matrix array formed by the same measuring rods just covers the measured plane of the lithium ion soft package battery, and the distance between two adjacent measuring rods in the same extending direction of the matrix array is equal.

The measuring method applied to the flatness measuring device of the lithium ion soft package battery comprises the following steps:

s1, placing the lithium ion soft package battery to be tested on a matrix array formed by a plurality of same measuring rods;

s2, measuring the pressure value obtained by each measuring probe;

s3, reading pressure values measured by the measuring rods through an acquisition card to form a pressure value matrix, and calculating and outputting a flatness coefficient K:

K＝1-Std/Ave

in the formula, K is the flatness coefficient of the lithium ion soft package battery; std is the standard deviation of all elements in the pressure value matrix; ave is the average of all elements in the pressure value matrix.

Examples

The invention is further described with reference to the following figures and detailed description.

The nominal capacity of a certain lithium ion soft package battery is 10Ah, the anode is made of ternary materials, the nominal voltage is 3.7V, the length is 220mm, the width is 130mm, the thickness is 6mm, and the flatness of the bottom surface of the lithium ion soft package battery with the size of 220mm multiplied by 130mm is measured by using a lithium ion soft package battery flatness measuring device.

The schematic diagram of the flatness measuring device of the lithium ion soft package battery is shown in figure 1. In fig. 1, (1) is the lithium ion soft package battery to be measured, (2) is the measuring rod, (3) is the base, (4) is the acquisition card, and the ellipses "… …" in fig. 1 are used to represent other measuring rods (2) which are not shown. All the measuring rods (2) are the same and are in a vertical state. As shown in fig. 2, the measuring stick (2) includes a measuring probe (21), a support stick (22), and a signal line (23).

Please refer to fig. 1 and fig. 2, wherein, the upper and lower ends of the support rod (22) are respectively connected with the measuring probe (21) and the base (3) mechanically; the upper end and the lower end of the signal wire (23) are respectively and electrically connected with the acquisition card (4); the support rod (22) is of a hollow structure, and a signal wire (23) penetrates through the support rod; the measuring probe (21) is made of piezoelectric ceramics and the top end is a horizontal plane.

In the embodiment, a rectangular array is formed by 22 × 13 measuring rods, the diameter of each measuring rod is 2mm, and the distance between two adjacent measuring rods (2) in the row direction and the column direction of the rectangular array is 10mm, so that the matrix array formed by the measuring rods (2) just covers the measured plane of the lithium ion soft package battery (1) with the size of 220mm × 130 mm.

Before formal measurement, a flat plate with the same three-dimensional size, the same weight and the smooth surface as that of the lithium ion soft package battery to be measured is used for calibrating the device.

The operation of the calibration process is consistent with the flatness measuring method of the lithium ion soft package battery, namely the method comprises the following steps:

s1, placing the calibration object on a matrix array composed of a plurality of same measuring rods;

s2, measuring the pressure value obtained by each measuring probe;

s3, reading pressure values measured by the measuring rods through an acquisition card to form a pressure value matrix, and calculating and outputting a flatness coefficient K:

K＝1-Std/Ave

in the formula, K is the flatness coefficient of the calibration object; std is the standard deviation of all elements in the pressure value matrix; ave is the average of all elements in the pressure value matrix.

In this embodiment, the pressure values measured by the measuring rods are read by the acquisition card to form a 22 × 13 pressure value matrix, and the standard deviation and the average value of all elements in the matrix are 0.0004N and 0.0150N, respectively, so that the flatness coefficient K of the calibration object is 1-0.0004/0.0150 is 0.973.

For a flat plate used for calibration, the measured flatness coefficient K is required to be as close to 1 as possible. If the calibration result does not meet the requirement, the device needs to be checked and adjusted, the elements with larger deviation between the pressure value and the average value in the pressure value matrix are focused, and the measuring rod needing to be checked and adjusted is positioned according to the positions of the elements.

The calibration result of the embodiment basically meets the requirement, so the flatness of the tested lithium ion soft package battery is formally measured by using the device. The measuring steps refer to the calibration process, but the calibration object is replaced by the lithium ion soft package battery to be measured. According to the measurement result, the standard deviation and the average value of all elements in the pressure value matrix are respectively 0.0037N and 0.0152N, so that the flatness coefficient K of the calibration object is 1-0.0037/0.0152-0.757, which indicates that the measured plane of the measured ion soft package battery has a certain degree of unevenness.

It should be noted that in some application occasions, the situation that the to-be-measured plane of the lithium ion soft package battery is smaller than the coverage range of the matrix array formed by the measuring rods (2) may occur, and in this situation, only the electrical connection between the acquisition card (4) and part of the signal lines (23) needs to be disconnected, so that the situation that the to-be-measured plane of the lithium ion soft package battery (1) is just covered by the matrix array formed by the measuring rods (2) is ensured, and the flatness measuring device of the lithium ion soft package battery does not need to be manufactured again or the number of the measuring rods (2) is reduced.

According to the flatness measuring device and method for the lithium ion soft package battery provided by the embodiment, aiming at the fact that the mass distribution of each position of the lithium ion soft package battery is approximately equal, the lithium ion soft package battery is placed on each horizontal plane at the top end of the matrix array of the measuring rod, and pressure data of each position is obtained through the measuring probe made of piezoelectric ceramics. If the surface of the lithium ion soft package battery, which is in contact with the measuring rod, is uneven, the pressure value measured by the measuring rod at the concave part is higher, the pressure value measured by the measuring rod at the convex part is lower, and the standard deviation of all elements in the pressure value matrix formed by the pressure values measured by the measuring rods is larger, so that the measuring method is objective and scientific, is simple and easy to implement, and has good stability of the measuring result aiming at the same type of battery. The supporting rod of the measuring device is of a hollow structure, and a signal wire penetrates through the supporting rod, so that the structure is compact, the supporting rod and the signal wire inside the supporting rod are convenient to check and maintain, and if a problem occurs in a certain measuring rod, the measuring rod can be conveniently and independently replaced. In addition, the whole flatness measuring device for the lithium ion soft package battery is simple in structure, easy to customize and high in precision.