Testing device and method for lithium ion battery and protection equipment thereof

Abstract

The invention discloses a test device and method for a lithium ion battery and protection equipment thereof, and the test device comprises a constant-temperature box body, a suction device, a battery clamping assembly, a heating device clamping assembly, a heat insulation layer clamping assembly, and a data measurement device. A first guide rail and a second guide rail which are distributed in parallel are fixed on a bottom platform in the incubator body; the suction device is mounted at the top of the incubator body and communicated with the incubator body; the battery clamping assembly is installed on the first guide rail through a first locking sliding block. The heating device clamping assembly is installed on the first guide rail through a second locking sliding block and corresponds to the battery clamping assembly in position. The heat insulation layer clamping assembly is installed on the second guide rail through a third locking sliding block. And the data measuring device is electrically connected with the battery. According to the invention, the safety test can be carried out on the lithium ion battery and the protection equipment thereof under the thermal abuse condition.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium ion battery testing, and more particularly to a testing device and method for lithium ion batteries and protective equipment thereof. Background Art

[0002] With the development of electric vehicles, the safety of lithium-ion batteries has attracted more and more attention. When a lithium-ion battery experiences thermal runaway, the release of a large amount of heat will provide an environmental condition for thermal abuse, which can easily cause the spread of thermal runaway in the battery pack. Therefore, the use of thermal insulation and flame retardant equipment to block thermal abuse can prevent the spread of thermal runaway in lithium-ion batteries. Thermal insulation and flame retardant equipment mainly refers to thermal insulation materials with certain thermal insulation and flame retardant properties. This material is generally a plate-like solid with a certain thickness, that is, a thermal insulation layer. At present, there are many studies on the thermal runaway phenomenon of lithium-ion batteries triggered under thermal abuse conditions, but there is a lack of research on the performance of thermal barrier equipment and the impact of this equipment on lithium-ion batteries under thermal abuse conditions.

[0003] Therefore, providing a test device and method for lithium-ion batteries and protective equipment thereof is an urgent problem to be solved by those skilled in the art.

[0004] invention

[0005] In view of this, the present invention provides a test device and method for lithium-ion batteries and protective equipment thereof, which can be used to study thermal runaway of lithium-ion batteries under thermal abuse conditions, and can also be used to conduct experimental research on thermal abuse protection equipment on this basis.

[0006] In order to achieve the above object, the present invention adopts the following technical solution:

[0007] A lithium-ion battery testing device comprises a thermostatic box body, a suction device, a battery clamping assembly, a heating device clamping assembly and a data measuring device, wherein a first guide rail is fixed on a bottom platform inside the thermostatic box body; the suction device is mounted on the top of the thermostatic box body and is connected; the battery clamping assembly is mounted on the first guide rail through a first locking slider; the heating device clamping assembly is mounted on the first guide rail through a second locking slider and corresponds to the position of the battery clamping assembly; the data measuring device is electrically connected to the battery.

[0008] By adopting the above technical solution, the beneficial effects of the present invention are:

[0009] Enables safety testing of lithium-ion batteries under thermal abuse conditions.

[0010] Furthermore, the data measuring device includes three thermocouples, a data acquisition instrument and a digital multimeter, one end of the three thermocouples are respectively fixed to the upper part of the battery close to the positive pole, the lower part close to the negative pole and the middle part, and the other ends of the three thermocouples are respectively electrically connected to the data acquisition instrument through wires; the digital multimeter is respectively electrically connected to the positive pole and negative pole of the battery through wires.

[0011] Furthermore, the battery clamping assembly includes a first connecting seat, a first threaded rod, a battery clamp and two first locking nuts, the first connecting seat is fixed on the first locking slider; the bottom of the first threaded rod is threadedly connected to the inner threaded hole of the first connecting seat; the battery clamp is sleeved on the smooth section of the first threaded rod and fixed by the two first locking nuts located above and below it.

[0012] Furthermore, the battery clamp includes a fixed arm, a movable arm, an adjustment bolt and an adjustment nut, the fixed arm is sleeved on the smooth section of the first threaded rod; the movable arm is connected to the fixed arm through the adjustment bolt and the adjustment nut.

[0013] Furthermore, the heating device clamping assembly includes a second connecting seat, a second threaded rod, a heating device clamp and two second locking nuts, the second connecting seat is fixed on the second locking slider; the bottom of the second threaded rod is threadedly connected to the inner threaded hole of the second connecting seat; the heating device clamp is sleeved on the smooth section of the second threaded rod and is fixed by two second locking nuts located above and below it.

[0014] Furthermore, the first locking slider and the second locking slider have the same structure, both comprising a slider and two locking bolts, the slider being embedded and mounted on the first guide rail; the two locking bolts are screwed on both sides of the slider respectively.

[0015] A lithium-ion battery protective equipment testing device comprises a thermal insulation layer clamping assembly and the lithium-ion battery testing device as described above, wherein a second guide rail parallel to the first guide rail is fixed to the bottom platform inside the thermostatic box body, and the thermal insulation layer clamping assembly is installed on the second guide rail through a third locking slider, and the third locking slider has the same structure as the first locking slider.

[0016] By adopting the above technical solution, the beneficial effects of the present invention are:

[0017] Enables safety testing of lithium-ion battery protection equipment under thermal abuse conditions.

[0018] Furthermore, the thermal insulation layer clamping assembly includes a third connecting seat, a third threaded rod, a thermal insulation layer clamp and two third locking nuts, the third connecting seat is fixed on the third locking slider; the bottom of the third threaded rod is threadedly connected to the inner threaded hole of the third connecting seat; the thermal insulation layer clamp is sleeved on the smooth section of the third threaded rod and is fixed by the two third locking nuts located above and below it; the thermal insulation layer clamp has the same structure as the battery clamp.

[0019] A lithium-ion battery testing method is carried out using a lithium-ion battery testing device as described above, and includes the following steps: firstly, a battery is mounted on a battery fixture, a heating device is mounted on a heating device fixture, and then the heating device heats the battery, the power used by the heating device is recorded, and the battery voltage and temperature data are monitored at the same time, heating is stopped after the battery has thermal runaway, a suction device is turned on to exhaust toxic gases from a thermostat box, and data from the thermal runaway test are analyzed to obtain the time t required for the battery from the start of heating to the occurrence of an internal short circuit, as well as the battery surface temperature Ti at the time of the internal short circuit.

[0020] A lithium-ion battery protection equipment test method is performed using the lithium-ion battery protection equipment test device as described above, and includes the following steps: firstly, a battery is mounted on a battery fixture, a heating device is mounted on a heating device fixture, then the heating device heats the battery, the power used by the heating device is recorded, and the voltage and temperature data of the battery are monitored at the same time; after the battery has thermal runaway, the heating is stopped, the suction device is turned on to discharge the toxic gas, and the data in the thermal runaway test are analyzed to obtain the time t required for the battery from the start of heating to the occurrence of an internal short circuit, and the battery surface temperature Ti at the time of the internal short circuit, and the safety factor a of the heating time is set according to the required setting; then, a heat insulation layer is mounted on the heat insulation layer fixture, the heat insulation layer is placed between the battery and the heating device, the heating power of the heating device remains unchanged, the heating time is set to a·t, and the voltage and temperature changes of the battery are monitored during the heating process. If the battery has an internal short circuit during the heating process, it is considered that the heat insulation layer cannot prevent thermal abuse and protect the safety of the battery. If the battery has no internal short circuit after the heating is completed, and the surface temperature is always lower than T, it is considered that the heat insulation layer can protect the safety of the battery under thermal abuse conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0022] Figure 1The accompanying drawing is a schematic diagram of the three-dimensional structure of a lithium-ion battery testing device in Example 1 provided by the present invention;

[0023] Figure 2 The accompanying drawing is a front view of a lithium ion battery testing device in Example 1 provided by the present invention;

[0024] Figure 3 The accompanying drawing is a schematic diagram of the three-dimensional structure of a lithium-ion battery protection equipment test device in Example 2 provided by the present invention;

[0025] Figure 4 The accompanying drawing is a front view of a lithium-ion battery protection equipment test device in Example 2 provided by the present invention;

[0026] Figure 5 The accompanying drawing is a schematic structural diagram of a battery clamp provided by the present invention;

[0027] Figure 6 The accompanying drawing is a schematic structural diagram of a first locking slider provided by the present invention. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] Embodiment 1:

[0030] like Figure 1 , 2 As shown in Figures 5 and 6, an embodiment of the present invention discloses a lithium-ion battery test device, including a thermostat box body 1, a suction device 2, a battery clamping assembly 3, a heating device clamping assembly 4 and a data measuring device. A first guide rail 11 is fixed on the bottom platform inside the thermostat box body 1; the suction device 2 is installed on the top of the thermostat box body 1 and is connected; the battery clamping assembly 3 is installed on the first guide rail 11 through a first locking slider 5; the heating device clamping assembly 4 is installed on the first guide rail 11 through a second locking slider 6, and corresponds to the position of the battery clamping assembly 3; the data measuring device is electrically connected to the battery. The present invention can test lithium-ion batteries under thermal abuse conditions.

[0031] Specifically, the data measuring device includes three thermocouples, a data acquisition instrument and a digital multimeter. One ends of the three thermocouples are respectively fixed on the upper part of the battery near the positive pole, the lower part near the negative pole and the middle part. The other ends of the three thermocouples are respectively electrically connected to the data acquisition instrument through wires to monitor and record the battery surface temperature data, and output the temperature signal to the data acquisition instrument to perform real-time data recording; the digital multimeter is electrically connected to the positive and negative poles of the battery through wires, respectively, for real-time recording and monitoring of the battery voltage. In this embodiment, the data acquisition instrument and the digital multimeter are placed outside the thermostat box body 1, and the wires enter the thermostat box body 1 through small holes on the side of the thermostat box body 1.

[0032] Specifically, the battery clamping assembly 3 includes a first connecting seat 31, a first threaded rod 32, a battery clamp 33 and two first locking nuts 34. The first connecting seat 31 is fixed on the first locking slider 5; the bottom of the first threaded rod 32 is threadedly connected to the internal threaded hole of the first connecting seat 31; the battery clamp 33 is fitted on the smooth section (without the threaded section) of the first threaded rod 32 and is fixed by two first locking nuts 34 located above and below it. The battery clamp 33 can rotate freely and adjust the height on the first threaded rod 32, and is fixed in height by the two first locking nuts 34.

[0033] Specifically, the battery clamp 33 includes a fixed arm 331, a movable arm 332, an adjusting bolt 333 and an adjusting nut 334. The fixed arm 331 is sleeved on the smooth section of the first threaded rod 32; the movable arm 332 is connected to the fixed arm 331 through the adjusting bolt 333 and the adjusting nut 334, so that the distance between the movable arm 332 and the fixed arm 331 can be adjusted to accommodate cylindrical batteries of different models and sizes.

[0034] Specifically, the heating device clamping assembly 4 includes a second connecting seat 41, a second threaded rod 42, a heating device clamp 43 and two second locking nuts 44. The second connecting seat 41 is fixed on the second locking slider 6; the bottom of the second threaded rod 42 is threadedly connected to the inner threaded hole of the second connecting seat 41; the heating device clamp 43 is sleeved on the smooth section of the second threaded rod 42 and is fixed by two second locking nuts 44 located above and below it.

[0035] Specifically, the first locking slider 5 and the second locking slider 6 have the same structure, both including a slider 51 and two locking bolts 52. The slider 51 is embedded and installed on the first guide rail 11; the two locking bolts 52 are respectively screwed on both sides of the slider 51, and the locking and fixing function is achieved by tightening the locking bolts 52. The locking bolts 52 can be screwed down until they contact the first guide rail 11, squeeze and lock. After loosening the locking bolts 52, the slider can move freely horizontally and linearly on the first guide rail 11.

[0036] The embodiment of the present invention also discloses a lithium ion battery test method, which is carried out using a lithium ion battery test device as described above, and includes the following steps: first, a battery is installed on a battery fixture 33, a heating device is installed on a heating device fixture 43, and then the heating device heats the battery, the power used by the heating device is recorded, and the battery voltage and temperature data are monitored at the same time. After the battery has thermal runaway, the heating is stopped, and the suction device 2 is turned on to discharge the toxic gas from the thermostat box 1, and the data in the thermal runaway test are analyzed to obtain the time t required for the battery from the start of heating to the occurrence of an internal short circuit, and the battery surface temperature Ti at the time of the internal short circuit. When an internal short circuit occurs in the battery, it can be considered that the internal structure of the battery is damaged and the battery enters an unstable stage. This phenomenon can be judged by monitoring the battery voltage data. When the battery voltage drops sharply, it can be considered that the battery has an internal short circuit. In addition, the test device for studying thermal runaway of lithium ion batteries triggered by thermal abuse conditions can also be used to study related issues related to thermal runaway, that is, to adjust the heating power, battery model, heating equipment and battery spacing, etc.

[0037] The surface temperature T of the battery at a certain moment is obtained by taking the average value of the temperatures measured by three thermocouples attached to the surface of the battery. The real-time surface temperatures of the battery measured by the three thermocouples are recorded as T1, T2 and T3 respectively, so that T = (T1 + T2 + T3) / 3 at each moment can be calculated. Similarly, the surface temperature T at the moment when the battery has an internal short circuit can also be obtained. The data of the corresponding relationship between temperature, battery voltage and time are processed and recorded by a computer, so that the instantaneous temperature rise rate T' and the average temperature rise rate Ta' can be obtained, and the relevant characteristics of the battery can be studied. The safety factor a of the heating time can be set according to the reference material or its own needs. For different experiments, the type of lithium-ion battery, the type of insulation layer, or the heating power can be changed, and the first and second parts of the experiment can be repeated to conduct different types of exploratory experiments.

[0038] Embodiment 2:

[0039] like Figure 3 , 4 As shown in Figures 5 and 6, the embodiment of the present invention discloses a lithium-ion battery protection equipment test device, including a heat insulation layer clamping assembly 7 and a lithium-ion battery test device as in Example 1, a second guide rail 12 parallel to the first guide rail 11 is fixed on the bottom platform inside the thermostatic box body 1, and the heat insulation layer clamping assembly 7 is installed on the second guide rail 12 through a third locking slider 8, and the third locking slider 8 has the same structure as the first locking slider 5. The present invention can test lithium-ion battery protection equipment under thermal abuse conditions.

[0040] Specifically, the insulation layer clamping assembly 7 includes a third connecting seat 71, a third threaded rod 72, an insulation layer clamp 73 and two third locking nuts 74. The third connecting seat 71 is fixed on the third locking slider 8; the bottom of the third threaded rod 72 is threadedly connected to the inner threaded hole of the third connecting seat 71; the insulation layer clamp 73 is sleeved on the smooth section of the third threaded rod 72 and is fixed by two third locking nuts 74 located above and below it; the insulation layer clamp 73 has the same structure as the battery clamp 33, and the clamping width can be changed to adapt to insulation layers of different thicknesses.

[0041] The embodiment of the present invention also discloses a lithium-ion battery protection device test method, which is carried out using the above lithium-ion battery protection device test device, and includes the following steps: first, a battery is installed on a battery fixture 33, a heating device is installed on a heating device fixture 43, and then the heating device heats the battery, the power used by the heating device is recorded, and the voltage and temperature data of the battery are monitored at the same time, the heating is stopped after the battery has thermal runaway, the suction device 2 is turned on to discharge the toxic gas, and the data in the thermal runaway test are analyzed to obtain the time t required for the battery from the start of heating to the occurrence of an internal short circuit, and the battery surface temperature T at the time of the internal short circuit. i, a safety factor a for the heating time is set as required; then the insulation layer is installed on the insulation layer fixture 73, and the insulation layer is placed between the battery and the heating device. The heating power of the heating device remains unchanged, and the heating time is set to a·t. During the heating process, the voltage and temperature changes of the battery are monitored. If an internal short circuit occurs in the battery during the heating process, it is considered that the insulation layer cannot prevent thermal abuse and protect the safety of the battery. If no internal short circuit occurs in the battery after the heating is completed, and the surface temperature is always lower than T, it is considered that the insulation layer can protect the safety of the battery under thermal abuse conditions.

[0042] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0043] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A lithium ion battery testing device, characterized in that: It includes a constant temperature box body, a suction device, a battery clamping assembly, a heating device clamping assembly and a data measuring device, wherein a first guide rail is fixed on the bottom platform inside the constant temperature box body; the suction device is installed on the top of the constant temperature box body and is connected; the battery clamping assembly is installed on the first guide rail through a first locking slider; the heating device clamping assembly is installed on the first guide rail through a second locking slider and corresponds to the position of the battery clamping assembly; the data measuring device is electrically connected to the battery.

2. A lithium ion battery testing device according to claim 1, characterized in that: The data measuring device includes three thermocouples, a data acquisition instrument and a digital multimeter. One ends of the three thermocouples are respectively fixed to the upper part of the battery close to the positive pole, the lower part close to the negative pole and the middle part, and the other ends of the three thermocouples are respectively electrically connected to the data acquisition instrument through wires; the digital multimeter is respectively electrically connected to the positive pole and negative pole of the battery through wires.

3. A lithium ion battery testing device according to claim 2, characterized in that: The battery clamping assembly includes a first connecting seat, a first threaded rod, a battery clamp and two first locking nuts. The first connecting seat is fixed on the first locking slider; the bottom of the first threaded rod is threadedly connected to the inner threaded hole of the first connecting seat; the battery clamp is sleeved on the smooth section of the first threaded rod and fixed by the two first locking nuts located above and below it.

4. A lithium ion battery testing device according to claim 3, characterized in that: The battery clamp comprises a fixed arm, a movable arm, an adjusting bolt and an adjusting nut. The fixed arm is sleeved on the smooth section of the first threaded rod; the movable arm is connected to the fixed arm through the adjusting bolt and the adjusting nut.

5. A lithium ion battery testing device according to claim 4, characterized in that: The heating device clamping assembly includes a second connecting seat, a second threaded rod, a heating device clamp and two second locking nuts. The second connecting seat is fixed on the second locking slider; the bottom of the second threaded rod is threadedly connected to the inner threaded hole of the second connecting seat; the heating device clamp is sleeved on the smooth section of the second threaded rod and is fixed by two second locking nuts located above and below it.

6. A lithium ion battery testing device according to claim 5, characterized in that: The first locking slider and the second locking slider have the same structure, and both include a slider and two locking bolts. The slider is embedded and installed on the first guide rail; the two locking bolts are screwed on both sides of the slider respectively.

7. A lithium-ion battery protection equipment test device, characterized in that: It includes a thermal insulation layer clamping assembly and a lithium-ion battery testing device as described in claim 6, wherein a second guide rail parallel to the first guide rail is fixed on the bottom platform inside the thermostatic box body, and the thermal insulation layer clamping assembly is installed on the second guide rail through a third locking slider, and the third locking slider has the same structure as the first locking slider.

8. A lithium-ion battery protection equipment testing device according to claim 7, characterized in that: The thermal insulation layer clamping assembly includes a third connecting seat, a third threaded rod, a thermal insulation layer clamp and two third locking nuts, the third connecting seat is fixed on the third locking slider; the bottom of the third threaded rod is threadedly connected to the inner threaded hole of the third connecting seat; the thermal insulation layer clamp is sleeved on the smooth section of the third threaded rod and is fixed by the two third locking nuts located above and below it; the thermal insulation layer clamp has the same structure as the battery clamp.

9. A lithium ion battery testing method, performed using a lithium ion battery testing device as claimed in claim 6, characterized in that: The method comprises the following steps: firstly, installing a battery on a battery fixture, installing a heating device on a heating device fixture, then heating the battery with the heating device, recording the power used by the heating device, monitoring the battery voltage and temperature data at the same time, stopping heating after thermal runaway occurs in the battery, turning on a suction device to exhaust toxic gas from a thermostatic box body, analyzing the data in the thermal runaway test, and obtaining the time t required for the battery from the start of heating to the occurrence of an internal short circuit, as well as the battery surface temperature Ti at the time when the internal short circuit occurs.

10. A lithium-ion battery protection equipment testing method, performed using a lithium-ion battery protection equipment testing device as claimed in claim 8, characterized in that: The method comprises the following steps: firstly, a battery is mounted on a battery fixture, a heating device is mounted on a heating device fixture, and then the heating device heats the battery, the power used by the heating device is recorded, and the voltage and temperature data of the battery are monitored at the same time; after the battery has thermal runaway, the heating is stopped, the suction device is turned on to discharge the toxic gas, and the data in the thermal runaway test are analyzed to obtain the time t required for the battery from the start of heating to the occurrence of an internal short circuit, and the battery surface temperature Ti at the time of the internal short circuit, and the safety factor a of the heating time is set according to the requirements; then, a thermal insulation layer is mounted on the thermal insulation layer fixture, and the thermal insulation layer is placed between the battery and the heating device, the heating power of the heating device remains unchanged, the heating time is set to a·t, and the voltage and temperature changes of the battery are monitored during the heating process; if the battery has an internal short circuit during the heating process, it is considered that the thermal insulation layer cannot prevent thermal abuse and protect the safety of the battery; if the battery has no internal short circuit after the heating is completed, and the surface temperature is always lower than T, it is considered that the thermal insulation layer can protect the safety of the battery under thermal abuse conditions.

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