CN215680758U

CN215680758U - Sensor, battery cell and test equipment

Info

Publication number: CN215680758U
Application number: CN202121773634.2U
Authority: CN
Inventors: 李树贤; 张金荣; 于奥; 刘子琪; 杨红新; 高飞; 骆兆军
Original assignee: Svolt Energy Technology Co Ltd
Current assignee: Svolt Energy Technology Co Ltd
Priority date: 2021-07-30
Filing date: 2021-07-30
Publication date: 2022-01-28
Anticipated expiration: 2031-07-30

Abstract

The application discloses sensor includes: the device comprises a substrate, a pressure-sensitive element, a thermosensitive element and a reference electrode which are arranged on the substrate, and leads respectively connected with the pressure-sensitive element, the thermosensitive element and the reference electrode. The sensor can acquire the pressure, the temperature and the voltage inside the battery cell. Simultaneously, this application still discloses an electricity core and the test equipment who adopts above-mentioned sensor.

Description

Sensor, battery cell and test equipment

Technical Field

The application relates to the technical field of lithium ion batteries, in particular to a sensor, an electric core and test equipment.

Background

The lithium ion power battery faces many problems in the using process, for example, the temperature inside the battery cell changes due to the charging and discharging process; in addition, as the volume expansion and contraction of the positive and negative pole pieces are accompanied in the charging and discharging process, the battery cell is bound in the metal shell with fixed volume, and therefore, the battery cell is extruded by the metal shell; in the charging and discharging process, the voltage of the full battery can be monitored only, the voltages of the positive electrode and the negative electrode cannot be monitored, the overcharge and the overdischarge of the battery core are easily caused, the cycle service life of the battery core is shortened, and huge potential safety hazards are accompanied.

Therefore, it is important to monitor the temperature, pressure, and the distribution and value of the positive and negative electrode potentials during the use of the lithium ion power battery. At present, no test equipment capable of monitoring the temperature, the pressure, the distribution of positive and negative electrode potentials and numerical values of the lithium ion power battery in the using process exists.

Disclosure of Invention

The application provides a sensor, electric core, test equipment can acquire inside pressure, temperature and the voltage of electric core.

The application provides a sensor, includes:

the device comprises a substrate, a pressure-sensitive element, a thermosensitive element and a reference electrode which are arranged on the substrate, and leads respectively connected with the pressure-sensitive element, the thermosensitive element and the reference electrode.

In an exemplary embodiment, the pressure-sensitive element includes a pressure-sensitive resistor, and the conductive line includes two pressure signal lines connected to both ends of the pressure-sensitive resistor, respectively.

In an exemplary embodiment, the heat-sensitive element includes a thermocouple, and the lead wire includes two temperature signal wires connected to both ends of the thermocouple, respectively.

In an exemplary embodiment, the lead connected to the reference electrode is a potential signal line.

In an exemplary embodiment, the pressure sensitive element, the heat sensitive element and the reference electrode are disposed on the same surface of the substrate, the pressure sensitive element is disposed in the middle of the substrate, and the heat sensitive element and the reference electrode are disposed on both sides of the substrate, respectively.

In an exemplary embodiment, the thickness of the sensor is 0.3 mm.

The application provides a battery cell, include: the battery comprises a positive plate, a negative plate and a sensor, wherein the sensor is arranged between the positive plate and the negative plate, a first diaphragm is arranged between the sensor and the positive plate, a second diaphragm is arranged between the sensor and the negative plate, and a lead of the sensor is led out of a cover plate of the battery core;

the sensor comprises a substrate, a pressure-sensitive element, a thermosensitive element, a reference electrode and leads, wherein the pressure-sensitive element, the thermosensitive element and the reference electrode are arranged on the substrate, and the leads are respectively connected with the pressure-sensitive element, the thermosensitive element and the reference electrode.

In an exemplary embodiment, the thickness of the sensor is 0.3 mm.

In an exemplary embodiment, the battery cell is a laminated battery cell, and the sensor is disposed between adjacent one positive plate and one negative plate in the battery cell.

The application provides a test equipment includes:

the sensor is arranged inside the battery cell to be tested;

a test device, the test device comprising:

the pressure testing unit is electrically connected with the pressure-sensitive element in the sensor and is used for measuring the pressure inside the electric core to be tested according to the pressure signal acquired by the pressure-sensitive element;

the temperature testing unit is electrically connected with the thermosensitive element in the sensor and is used for measuring the temperature in the electric core to be tested according to the temperature signal acquired by the thermosensitive element;

the voltage testing unit is electrically connected with a reference electrode in the sensor and is used for measuring the voltage inside the to-be-tested battery cell according to a voltage signal acquired by the reference electrode;

In an exemplary embodiment, the thickness of the sensor is 0.3 mm.

In one exemplary embodiment, the test device includes a display screen;

the display screen is arranged to display the pressure, the temperature and the voltage inside the battery cell to be tested.

Additional features and advantages of the application will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the application. Other advantages of the present application may be realized and attained by the instrumentalities and combinations particularly pointed out in the specification and the drawings.

Drawings

The accompanying drawings are included to provide an understanding of the present disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the examples serve to explain the principles of the disclosure and not to limit the disclosure.

FIG. 1 is a schematic view of a sensor according to an embodiment of the present application;

fig. 2 is a schematic diagram of a battery cell according to an embodiment of the present application;

FIG. 3 is a schematic diagram of a test apparatus according to an embodiment of the present application;

FIG. 4 is a schematic diagram of a pressure-temperature-anode-cathode voltage variation testing apparatus according to an embodiment of the present application;

FIG. 5 is an assembly diagram of a pressure-temperature-anode-cathode voltage variation testing apparatus according to an embodiment of the present disclosure;

FIG. 6 is a diagram illustrating the resistance variation of the force sensitive resistor under different pressures in the apparatus for testing the pressure-temperature-anode-cathode voltage variation according to the embodiment of the present application;

fig. 7 is a diagram illustrating a cell internal temperature variation monitored by a pressure-temperature-positive and negative voltage variation testing apparatus according to an embodiment of the present application;

fig. 8 shows the positive voltage variation and the negative voltage variation monitored by the pressure-temperature-positive and negative voltage variation testing device according to the embodiment of the present application.

Detailed Description

Fig. 1 is a schematic diagram of a sensor according to an embodiment of the present application, and as shown in fig. 1, the sensor according to the present embodiment includes a substrate, a pressure-sensitive element, a heat-sensitive element, and a reference electrode disposed on the substrate, and leads respectively connected to the pressure-sensitive element, the heat-sensitive element, and the reference electrode.

In an exemplary embodiment, the thickness of the sensor is 0.3 mm. In other embodiments, the thickness of the sensor may also be other values, which is not limited herein.

The sensor of the embodiment of the application can acquire the pressure, the temperature and the voltage inside the battery core.

Fig. 2 is a schematic diagram of a battery cell according to an embodiment of the present application, and as shown in fig. 2, the battery cell according to the embodiment includes a positive plate, a negative plate, and a sensor; the sensor is arranged between the positive plate and the negative plate, a first diaphragm is arranged between the sensor and the positive plate, a second diaphragm is arranged between the sensor and the negative plate, and a lead of the sensor is led out of a cover plate of the battery core.

In one exemplary embodiment, the sensor includes a substrate, a pressure sensitive element, a temperature sensitive element, and a reference electrode disposed on the substrate, and leads respectively connected to the pressure sensitive element, the temperature sensitive element, and the reference electrode.

The electric core that this application embodiment provided acquires inside pressure, temperature and the voltage of electric core through arranging the inside sensor of electric core in.

FIG. 3 is a schematic diagram of a test apparatus including a sensor and a test device according to an embodiment of the present disclosure.

A test device, the test device comprising:

and the voltage testing unit is electrically connected with a reference electrode in the sensor and is used for measuring the voltage inside the electric core to be tested according to the voltage signal acquired by the reference electrode.

In one exemplary embodiment, the test device includes a display screen;

The test equipment provided by the embodiment of the application monitors the pressure, the temperature and the positive and negative potential specific numerical values inside the battery cell in the battery cell charging and discharging process, can record the change conditions of the numerical values above the charging and discharging process, can provide data for a Battery Management System (BMS), optimizes the service condition of the battery cell, and reduces the potential safety hazard in the use process.

Fig. 4 is a schematic diagram of a test apparatus for in-situ monitoring pressure-temperature-positive and negative electrode voltage changes in a cell during use of the cell according to an embodiment of the present application, as shown in fig. 4, including a pressure sensing region, a temperature sensing line and a reference electrode, and a data receiving device (not shown in the figure).

When pressure acts on the force sensitive resistor in the pressure sensing area, the resistance value changes along with the change of the pressure, so that the voltage value and the current value in the circuit are adjusted. Therefore, the pressure born by the pressure sensing area is calculated by testing the voltage value of the circuit.

The basic principle of the temperature sensing line is that two material conductors with different components form a closed loop, when temperature gradients exist at two ends, current is generated in the loop, and temperature change can be calculated by testing voltage change in the loop.

The reference electrode is prepared in a copper wire lithium plating mode, and the actual potentials of the positive electrode and the negative electrode in the charging and discharging process of the battery cell can be monitored through the reference electrode.

In an exemplary embodiment, the size of the testing device may be as shown in table 1, and in some other exemplary embodiments, the size of the testing device may be other sizes, which is not limited herein.

TABLE 1

Identification	Size (mm)
		Pressure sensing area	40*40
Temperature sensing wire	5.31
		Reference electrode	5.31
Thickness of	0.3

Taking a laminated battery cell as an example, the specific operation steps of detecting the pressure, temperature and voltage inside the battery cell by the sensor are as follows:

step 1: adding a layer of diaphragm on the negative pole piece of the battery core, and placing a pressure temperature voltage sensor on the diaphragm;

step 2: a layer of diaphragm is arranged on the pressure temperature voltage sensor, and an anode is superposed on the diaphragm;

and step 3: the subsequent cell fabrication is carried out according to the normal production of laminated cells, and the positive electrode, the diaphragm and the negative electrode are alternately superposed to form a pole group;

and 4, step 4: the pole group structure is as follows: negative electrode/membrane/pressure temperature voltage sensor/membrane/positive electrode/membrane/negative electrode/membrane/positive electrode/membrane/… …/positive electrode/membrane/negative electrode. The assembled structure is shown in fig. 5, wherein the thick straight line represents the negative electrode or the positive electrode, the thin straight line represents the diaphragm, and the sensor represents the pressure-temperature-positive and negative electrode voltage variation testing equipment, namely, a pressure-temperature voltage sensor.

And 5: normally, the production of the battery core is carried out, the lead of the sensor is led out from the battery core cover plate and is connected to the data receiving device, and the internal pressure, the temperature and the potential variation value of the anode and the cathode of the battery core are obtained through testing.

The resistance of the force sensitive resistor used in the experiment as a function of pressure is shown in figure 6. And the data receiving device obtains the internal pressure of the battery cell according to the received voltage or current of the pressure induction area. The data receiving device obtains the temperature change inside the battery cell according to the received voltage or current in the temperature sensing circuit (as shown in fig. 7). C in fig. 7 represents the battery charge/discharge capacity rate. 1C represents the current intensity at which the cell was fully discharged for one hour, for example a 18650 cell, nominally 2200mAh, was discharged at 1C intensity for 1 hour to completion, at which time the discharge current was 2200 mA. The charge-discharge multiplying power is equal to the ratio of the charge-discharge current to the rated capacity. For example, when the battery 20A having a rated capacity of 100A.h was discharged, the discharge rate was 0.2C. The cell discharge C rate, 1C, 2C, 0.2C, is a measure of the cell discharge rate, indicating how fast the discharge is. The used capacity is discharged after 1 hour, and the discharge is called 1C discharge; when the discharge was completed in 5 hours, the discharge was called 0.2C discharge.

The data receiving device also monitors the voltage changes of different positive electrodes and negative electrodes according to the reference electrode (as shown in figure 8). The SOC in fig. 8 refers to the state of charge of the battery, that is, the state of charge remaining in the battery, and the value of the SOC is defined as the ratio of the remaining charge remaining in the battery to the rated charge capacity of the battery, expressed in terms of percentage. The value range is 0-1, which indicates that the battery is completely discharged when the SOC is 0 and indicates that the battery is completely charged when the SOC is 1.

The test equipment provided by the embodiment of the application monitors the specific numerical values of the pressure, the temperature and the positive and negative electric potentials inside the battery cell in the battery cell charging and discharging process, can record the change conditions of the numerical values above the charging and discharging process, can provide data for a Battery Management System (BMS), optimizes the service condition of the battery cell, and reduces the potential safety hazard in the use process.

The present application describes embodiments, but the description is illustrative rather than limiting and it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible within the scope of the embodiments described herein. Although many possible combinations of features are shown in the drawings and discussed in the detailed description, many other combinations of the disclosed features are possible. Any feature or element of any embodiment may be used in combination with or instead of any other feature or element in any other embodiment, unless expressly limited otherwise.

The present application includes and contemplates combinations of features and elements known to those of ordinary skill in the art. The embodiments, features and elements disclosed in this application may also be combined with any conventional features or elements to form a unique inventive concept as defined by the claims. Any feature or element of any embodiment may also be combined with features or elements from other inventive aspects to form yet another unique inventive aspect, as defined by the claims. Thus, it should be understood that any of the features shown and/or discussed in this application may be implemented alone or in any suitable combination. Accordingly, the embodiments are not limited except as by the appended claims and their equivalents. Furthermore, various modifications and changes may be made within the scope of the appended claims.

Further, in describing representative embodiments, the specification may have presented the method and/or process as a particular sequence of steps. However, to the extent that the method or process does not rely on the particular order of steps set forth herein, the method or process should not be limited to the particular sequence of steps described. Other orders of steps are possible as will be understood by those of ordinary skill in the art. Therefore, the particular order of the steps set forth in the specification should not be construed as limitations on the claims. Further, the claims directed to the method and/or process should not be limited to the performance of their steps in the order written, and one skilled in the art can readily appreciate that the sequences may be varied and still remain within the spirit and scope of the embodiments of the present application.

It will be understood by those of ordinary skill in the art that all or some of the steps of the methods, systems, functional modules/units in the devices disclosed above may be implemented as software, firmware, hardware, and suitable combinations thereof. In a hardware implementation, the division between functional modules/units mentioned in the above description does not necessarily correspond to the division of physical components; for example, one physical component may have multiple functions, or one function or step may be performed by several physical components in cooperation. Some or all of the components may be implemented as software executed by a processor, such as a digital signal processor or microprocessor, or as hardware, or as an integrated circuit, such as an application specific integrated circuit. Such software may be distributed on computer readable media, which may include computer storage media (or non-transitory media) and communication media (or transitory media). The term computer storage media includes volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data, as is well known to those of ordinary skill in the art. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, Digital Versatile Disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can accessed by a computer. In addition, communication media typically embodies computer readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media as known to those skilled in the art.

Claims

1. A sensor, comprising:

2. The sensor of claim 1, wherein:

the pressure-sensitive element comprises a pressure-sensitive resistor, and the lead comprises two pressure signal wires which are respectively connected with two ends of the pressure-sensitive resistor.

3. The sensor of claim 1, wherein:

the thermosensitive element comprises a thermocouple, and the lead comprises two temperature signal wires respectively connected with two ends of the thermocouple.

4. The sensor of claim 1, wherein:

and the lead connected with the reference electrode is a potential signal wire.

5. The sensor of claim 1, wherein:

the pressure-sensitive element, the thermosensitive element and the reference electrode are arranged on the same surface of the substrate, the pressure-sensitive element is arranged in the middle of the substrate, and the thermosensitive element and the reference electrode are respectively arranged on two sides of the substrate.

6. The sensor of claim 1, wherein:

the thickness of the sensor is 0.3 mm.

7. The utility model provides an electricity core, includes positive plate and negative pole piece, its characterized in that:

the battery pack further comprises a sensor according to any one of claims 1 to 6, wherein the sensor is arranged between the positive plate and the negative plate, a first diaphragm is arranged between the sensor and the positive plate, a second diaphragm is arranged between the sensor and the negative plate, and a lead of the sensor is led out of a cover plate of the battery core.

8. The cell of claim 7, wherein:

the battery core is a laminated battery core, and the sensor is arranged between an adjacent positive plate and an adjacent negative plate in the battery core.

9. A test apparatus, comprising:

the sensor of any one of claims 1 to 5, disposed inside a cell under test;

a test device, the test device comprising:

10. The test apparatus of claim 9, wherein:

the test equipment comprises a display screen;